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A 66-year-old woman with a complex medical history underwent transcatheter mitral valve replacement (TMVI) owing to mitral insufficiency. Risk factors and noncompliance led to bioprosthetic valve thrombosis (BPVT) within 3 years. Emergent surgery indicated by an ad hoc heart team successfully managed the situation, showcasing challenges in BPVT management after TMVI.
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BACKGROUND: A paradox of lower morbidity and mortality in overweight or obese patients undergoing cardiac surgery has been described; however, knowledge about the influence of obesity in patients with acute Type A aortic dissection (AAD) is limited. This study aimed to evaluate the effect of obesity on short- and long-term outcomes after surgical treatment for AAD. METHODS: Between 01/2004 and 12/2022, 912 patients with a BMI of 18.5 or greater were operated on for AAD. Patients were grouped according to their BMI (normal weight: BMI 18.5-24.9, n = 332; overweight: BMI 25-29.9, n = 367; obesity class I: BMI 30-34.9, n = 133; obesity class II+: BMI ≥ 35, n = 67), and the obtained clinical and surgical data were compared. RESULTS: Obese patients were younger at the time of AAD (p = 0.001) and demonstrated higher rates of typical cardiovascular comorbidities (arterial hypertension, p = 0.005; diabetes mellitus, p < 0.001). The most important preoperative parameters, as well as the surgical approach, were similar between all four groups. The occurrence of renal failure requiring dialysis was higher in patients with BMI ≥ 35 (p = 0.010), but the in-hospital (p = 0.461) and long-term survival (p = 0.894) showed no significant differences. CONCLUSIONS: There are no indications that the obesity paradox is applicable in the setting of AAD. Since obese patients are affected by AAD at a younger age, obesity might constitute a risk factor for AAD. However, obesity does not influence short- or long-term survival. Regardless of body weight, immediate surgical therapy remains the treatment of choice for AAD.
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Current diagnostic methods for detecting foodborne pathogens are time-consuming, require sophisticated equipment, and have a low specificity and sensitivity. Magnetic nanoparticles (MNPs) and plasmonic/colorimetric biosensors like gold nanoparticles (GNPs) are cost-effective, high-throughput, precise, and rapid. This study aimed to validate the use of MNPs and GNPs for the early detection of Escherichia coli O157:H7, Salmonella enterica spp., Campylobacter jejuni, and Listeria monocytogenes in bovine fecal samples. The capture efficiency (CE) of the MNPs was determined by using Salmonella Typhimurium (ATCC_13311) adjusted at an original concentration of 1.5 × 108 CFU/mL. One (1) mL of this bacterial suspension was spiked into bovine fecal suspension (1 g of fecal sample in 9 mL PBS) and serially diluted ten-fold. DNA was extracted from Salmonella Typhimurium to determine the analytical specificity and sensitivity/LOD of the GNPs. The results showed that the CE of the MNPs ranged from 99% to 100% and could capture as little as 1 CFU/mL. The LOD of the GNPs biosensor was 2.9 µg/µL. The GNPs biosensor was also tested on DNA from 38 naturally obtained bovine fecal samples. Out of the 38 fecal samples tested, 81.6% (31/38) were positive for Salmonella enterica spp., 65.8% (25/38) for C. jejuni, 55.3% (21/38) for L. monocytogenes, and 50% (19/38) for E. coli O157:H7. We have demonstrated that MNP and GNP biosensors can detect pathogens or their DNA at low concentrations. Ensuring food safety throughout the supply chain is paramount, given that these pathogens may be present in cattle feces and contaminate beef during slaughter.
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Introduction: The management of aortic dissection has evolved significantly over the decades, with the frozen elephant trunk (FET) procedure emerging as a key technique for treating complex aortic pathologies. Recent practices involve deploying the FET prosthesis more proximally in the aorta (Zone 0) to reduce complications, leading to questions about its impact on long-term aortic remodeling compared to traditional Zone 2 deployment. Methods: This retrospective analysis utilized 3D segmentation software to assess the volumetric changes in aortic remodeling after acute Type A aortic dissections, comparing FET stent graft deployment in Zone 0 and Zone 2. The study included 27 patients operated on between 2020 and 2022, with volumetric measurements taken from postoperative and 6-month follow-up CT scans. Statistical analyses were performed to evaluate the differences in the aortic true lumen (TL) and the perfused false lumen (PFL) between the two groups. Results: Both Zone 0 and Zone 2 deployments resulted in significant true lumen (TL) increases (Z0 p = 0.001, Z2 p < 0.001) and perfused false lumen (PFL) decreases (Z0 p = 0.02, Z2 p = 0.04), with no significant differences in volumetric changes between the groups (p = 0.7 post op and p = 0.9 after 6 months). The distal anastomosis in Zone 0 did not compromise the aortic remodeling outcomes and was associated with reduced distal ischemia and cerebral perfusion times (p = 0.041). The angle measurements in Zone 0 did not show any significant changes after the 6-month control (p = 0.2). However, in Zone 2, a significant change was detected. (p = 0.022). The part comparison analyses did not indicate significant differences in aortic deviation between the groups (p = 0.62), suggesting comparable effectiveness in aortic remodeling. Conclusions: Performing the distal anastomosis more proximally in Zone 0 offers technical advantages without compromising the effectiveness of aortic remodeling compared to the traditional Zone 2 deployment. This finding supports the continued recommendation of Zone 0 deployment in the management of acute Type A aortic dissections, with ongoing studies being needed to confirm the long-term outcomes and survival benefits.
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Autoimmune hypophysitis (AH) is an uncommon condition where there is inflammation of the pituitary gland which leads to hormonal imbalances. It is often associated with autoimmune diseases; however, a case is yet to be reported with an association of AH with seronegative rheumatoid arthritis (RA). We present a case of a 45-year-old female who complained of polyuria/polydipsia and rapid weight gain. An MRI of the head revealed enlargement of the pituitary gland, concerning for AH. Although she was initially treated for diabetes insipidus, she began reporting new complaints of joint pains and morning stiffness. She was clinically diagnosed with seronegative RA and improved with a trial of hydroxychloroquine. A repeat MRI showed improvement in the abnormal pituitary findings, and the patient was closely monitored with a multidisciplinary approach. Diagnosing and managing patients with AH are topics that are still being explored and researched as it is a relatively rare pathology. Consequently, we found the need to discuss the relationship of AH with seronegative RA and delve into the various diagnostic and treatment approaches.
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This work explores the effects of solvent polarity on Janus Green B (JGB) photophysical properties. The Lippert-Mataga, Billot, and Ravi equations were utilized to calculate the singlet-state excited dipole moments (µe) and ground state dipole moments (µg) using absorption and fluorescence spectra analyses. The results showed an increase in the former, which is suggestive of electronic structural alterations upon excitation. Analysis of fluorescence quantum yield values revealed that JGB's environment had an impact on its emission characteristics; it was particularly sensitive to silver nanoparticles, suggesting possible interactions. While simulations of electron density, electrostatic potential, and energy gap (Eg) helped to understand the electronic structure of JGB, theoretical absorption spectra produced by Time Dependent Density Function Theory (TD-DFT) calculations offered insights into electronic transitions during absorption. To sum up, the present study contributes to our comprehension of the molecular behavior of JGB in various solvents by elucidating the intricate relationship among solvent polarity, molecular environment, and interactions with silver nanoparticles. Additionally, theoretical computations support the interpretation of experimental results.
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This study embarked on an exploration into the genetic structure and evolutionary history of the Chrysichthys auratus species, leveraging PCR amplification, phylogenetic trees, and haplotype networks. Specific DNA segments were successfully amplified and visualized through electrophoresis. Newly obtained sequences were Bank into GenBank and given accession numbers (OR730807-OR730808-OR730809). The Neighbor-Joining method provided insights into the evolutionary relationships among taxa, further augmented by bootstrap values and the Tamura 3-parameter method. A comprehensive geographical haplotype network showcased pronounced genetic differentiation, especially between remote populations. Nonetheless, shared haplotypes between proximate regions indicated either ancestral genetic connections or ongoing gene flow. Employing the COI-DNA barcodes, an in-depth understanding of intra- and inter-populational genetic diversity was achieved. The study's findings unravel the intricate genetic landscape and evolutionary dynamics of C. auratus, offering novel perspectives into its demographic history across its vast native habitat.
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Código de Barras del ADN Taxonómico , Haplotipos , Filogenia , Filogeografía , Animales , Código de Barras del ADN Taxonómico/métodos , Evolución Molecular , Variación Genética , Carpa Dorada/genética , Carpa Dorada/clasificación , Flujo Génico , Complejo IV de Transporte de Electrones/genéticaRESUMEN
Background and Objectives: Acute type A aortic dissection (AAD) is a life-threatening disease. No differences between men and women have been made in the treatment of AAD so far and knowledge about sex differences regarding long-term outcomes is limited. Materials and Methods: Between 01/2004 and 12/2021, 874 patients were operated on for AAD, including 313 (35.8%) women and 561 (64.2%) men. Clinical and surgical records, including long-term follow-up information, were obtained and analyzed retrospectively. To account for differences in the outcome determined by different preoperative life expectancies, a subgroup analysis for a set of patients matched according to their remaining life expectancy was performed. Results: At the time of AAD, women were older than men (69.1 ± 13.0 vs. 61.8 ± 13.3 years, p < 0.001) and had a shorter remaining statistical life expectancy (18.6 ± 10.8 vs. 21.4 ± 10.4 years, p < 0.001). Significantly more DeBakey type II AAD was found in women (37.1% vs. 25.7%, p < 0.001). Comorbidities and preoperative status at the time of presentation were similar in women and men. More hemiarch procedures (63.3% vs. 52.0%, p < 0.001) and less arch replacements (8.6% vs. 16.6%, p < 0.001) were performed in women, resulting in shorter cross-clamp times for women (92 ± 39 vs. 102 ± 49 min, p < 0.001). The in-hospital mortality was similar in women and men (11.5% vs. 12.7%, p = 0.618). Long-term survival was significantly shorter in women compared to men (9.8 [8.1-11.5] vs. 15.1 [11.9-18.4] years, p = 0.011). A matched subgroup analysis revealed that when comparing groups with a similar remaining life expectancy, the long-term survival showed no significant differences between women and men (9.8 [7.9-11.6] vs. 12.4 [10.1-14.7] years, p = 0.487). Conclusions: There are sex differences in AAD, with DeBakey type II dissection being more frequent in women. The seemingly worse long-term outcome can mostly be attributed to the shorter remaining statistical life expectancy at the time of presentation.
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Disección Aórtica , Implantación de Prótesis Vascular , Humanos , Masculino , Femenino , Estudios Retrospectivos , Caracteres Sexuales , Resultado del Tratamiento , Disección Aórtica/cirugía , Factores de Riesgo , Enfermedad AgudaRESUMEN
The condensation of pyrrole-2,5-dicarbaldehyde (1) with 5-(2-amino-4-phenylthiazol-5-yl)-4-phenylthiazol-2-amine (2) and/or 5-(4-Amino-phenyl)-4-phenylthiazol-2-amine (3) gave new poly(Z)-N-((5-(iminomethyl)-1H-pyrrol-2-yl)methylene)-5-(2-((E)-(5-(iminomethyl)-I-pyrrol-2-yl)methyleneamino)-4-phenylthiazol-5-yl)-4-phenylthiaol-2-amine (P1) and/or poly(E)-N-((5-(iminomethyl)-1H-pyrrol-2-yl)methylene)-5-(4-((E)-(5-(iminomethyl)-1H-pyrrol-2-yl)methyleneamino)phenyl)-4-phenylthiaol-2-amine (P2) as a novel conjugated polymer by microwave irradiation and traditional heating.. It is evident that the microwave irradiation technique quickly raised the molecular weight of polyimines. In addition to quantifying the molecular weight of the resultant polyimines. All the polyimines were characterized using FTIR, XRD, H1NMR, TGA, and DSC. The optical characteristics of polyimine derivatives were investigated using a UV-Vis spectrophotometer. The absorption spectra showed a main absorption band around 372 nm for polyimine (P1) and 381 nm for polyimine (P2). The optical energy was calculated and found to be 2.49 and 2.68 eV. The photoluminescence of the polyimine derivatives was measured and analyzed by spectrofluorometer and Laser photoluminescence experiment and the emission color was studied using CIE graphs. The fluorescence spectra showed an emission peak at 548 nm for polyimine (P1) with yellow green color in CIE graph, while for polyimine (P2) the emission band was located at 440.5 nm with blue color in CIE graph. Photoluminescence quantum yield PLQY was measured for the polyimine P1 and P2 in both liquid and Solid states and indicated the AIE behavior of the polyimines. TD-DFT simulations were applied to the polyimine derivatives where the structures were geometrically optimized and the spectroscopic characterizations were evaluated.
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Introduction: Understanding tumor localization in multiparametric MRI (mpMRI) of the prostate is challenging for urologists but of great importance in mpMRI-fused prostate biopsy or radical prostatectomy. The aim was to evaluate the effectiveness of 3D printed models of the prostate to help urologists to locate tumors. Methods and Participants: 20 urologists from University Medical Center Mainz (Germany) were asked to plot the location of a cancer suspicious lesion (PI-RADS ≥ 4) on a total of 30â mpMRI on a prostate sector diagram. The following 3 groups (as matched triplets) were divided into: mpMRI only, mpMRI with radiological report and mpMRI with 3D printed model (scaled 1:1). Statistical analysis was performed using one-way and two-way ANOVA (with bonferroni post-test). Results: Overall, localization of the suspicious lesion was superior with the radiological report (median of max. 10 [IQR]: MRI 2 [IQR 1;5], MRI + report: 8 [6.3;9], MRI + 3D model 3 [1.3;5.8]; p < 0.001). Residents with <1 year of experience had a significantly higher detection rate using a 3D printed model [5 (5;5.8)] compared to mpMRI alone [1.5 (1;3.5)] (p < 0.05). Regarding the estimation of index lesion extension, the 3D model showed a significant benefit (mean percentage difference [95% CI]: MRI alone 234% [17.1;451.5], MRI + report 114% [78.5;149.6], MRI + 3D model 17% [-7.4;41.3] (p < 0.01). Conclusion: Urologists still need the written radiological report for a sufficient understanding of tumor localization. The effectiveness of the 3D printed model regarding tumor localization is particularly evident in young residents (<1 year) and leads to a better overall assessment of the tumor extension.
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The antibacterial activity of a variety of modified poly(methyl methacrylate) Schiff bases against common microbial infections and removal of methylene blue (MB) dye were screened. The Schiff bases were synthesized from the reaction of the modified (PMMA) with vanillin (PMMA)Van and cinnamaldehyde (PMMA)Cin. By using Fourier transformer infrared (FT-IR), X-ray diffraction analysis (XRD), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), the structures of the nanofibers of the synthesized Schiff bases were confirmed. The modified Kirky-Bauer method was used to screen the antibacterial activities of all the obtained materials against various bacterial species, including gram-positive bacterial (Bacillus subtilis (4k1p), Staphylococcus aureus), Gram-negative bacteria (Escherichia coli (7ab3), Pseudomonas aeruginosa). Inhibition zones against gram-positive bacteria ranged in diameter from 7 to 14 mm, whereas for the Gram-negative bacteria, the inhibition zones found to be ranged between 6 and 13 mm. With a minimum bactericidal concentration (MBC) of 8 mg/mL and a minimum inhibitory concentration (MIC) of 2 mg/mL, (PMMA)Van shown the greatest antibacterial activity. Lastly, molecular docking research was done to better understand the interactions between this series' targets and inhibitors for (PMMA)Van and (PMMA)Cin (4k1p and 7ab3). Molecular modeling of these surface-adsorbed polymers indicated that (PMMA)Van binds more strongly with Nitrogen than does (PMMA)Cin through extra hydrogen-bonding interactions. All the developed materials were evaluated for the removal of 0.1 g/L methylene blue dye (MB) from an aqueous solution. The elimination percentage of MB dye ranged from 26.67% by using 0.05 g powder of (PMMA)Cin to 85.63% by employing 0.05 g nanofibers of (PMMA)Van.
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Polimetil Metacrilato , Bases de Schiff , Polimetil Metacrilato/química , Simulación del Acoplamiento Molecular , Bases de Schiff/química , Espectroscopía Infrarroja por Transformada de Fourier , Azul de Metileno/farmacología , Antibacterianos/farmacología , Antibacterianos/química , Polímeros , Pruebas de Sensibilidad MicrobianaRESUMEN
Infective endocarditis is a severe medical condition that occurs when the endocardium of the heart gets infected by different microorganisms, including coagulase-negative staphylococci such as Staphylococcus lugdunensis. The source of infection is often related to procedures done in the groin area, such as femoral catheterization for cardiac catheterization, vasectomy, or central line placement in an already infected mitral or aortic valve. Herein, we are discussing a case of a 55-year-old female with a past medical history of end-stage renal disease on hemodialysis with a history of recurrent cannulation of her arteriovenous (AV) fistula. She presented with fever, myalgia, and generalized weakness, and was later found to have Staphylococcus lugdunensis bacteremia and infective endocarditis with mitral valve vegetations, for which the patient was transferred to the mitral valve specialized center for mitral valve replacement. This case acts as a reminder to consider recurrent cannulation of the AV fistula as one of the potential ports of entry of Staphylococcus lugdunensis to the body.
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A significant issue in cancer biology is finding anticancer therapies that effectively kill cancer cells. Through the use of several aldehydes, Schiff bases based on branched poly (p-hydroxy styrene) are created. The branched polymer is first chloroacetylated, then aminated with 1,4-phenylenediamine, and finally, aldehydes are reacted with the aminated polymer to produce the Schiff base compounds. Through the utilization of FTIR, TGA, XRD, NMR, and elemental analysis, all synthesized Schiff-bases are identified and characterized. Further, the antineoplastic potential of all Schiff bases is evaluated against different cancer cell lines. The results gained from this study indicate that the Schiff base polymers have cytotoxic power against cancer cells depending on cancer cell type and this antiproliferation potency is dose-concentration dependent. Importantly, the prepared S1 Schiff-base polymer shows potent cytotoxicity and is able to trigger the apoptosis and reactive oxygen species (ROS) in MCF-7 cells. Further, it downregulates VEGFR protein expression. The Schiff base polymers would have extensive applications in the biological disciplines.
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Antineoplásicos , Bases de Schiff , Humanos , Bases de Schiff/farmacología , Bases de Schiff/química , Células MCF-7 , Antineoplásicos/farmacología , Antineoplásicos/química , Aldehídos , Polímeros , EstirenosRESUMEN
Borate glasses (BG) doped with different amounts of ZnO (0-0.6 mol%) were formed by the traditional melt quenching technique. The different glasses so made were characterized using different characterization techniques such as X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscope (SEM), and UV-Vis absorption optical properties. The XRD patterns showed an amorphous structure with one broad peak at 2θ = 29°, while the phonons bands were studied in terms of the FTIR bands. Optical properties of the glasses were studied using UV-Vis absorption spectra in the range 190-1100 nm, in which the prominent band lies at about 261.5 nm of peak position, from which the bandgab (Eg) was calculated from its edge using Tauc's plot, with Eg ~ 3.5 eV. The laser irradiation showed no significant changes in the absorption bands, despite a significant change observed in the amorphous behavior in the XRD pattern. The cell viability was performed for two samples of the BG and 0.6 mol% ZnO doped using 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay method. The result showed better cell viability and low toxicity. So, ZnO doped BG can be used in various biomedical applications.
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OBJECTIVES: The island technique for reimplantation of supra-aortic vessels in frozen elephant surgery is commonly used but might be questioned for dissected vessels. This study analyses the remodelling of reimplanted supra-aortic vessels after FET in acute and chronic aortic dissection (CAD). METHODS: Between June 2017 and April 2021, 133 patients were operated for acute and CAD using the frozen elephant technique. The island technique for reimplantation of the supra-aortic vessels was used in 94/133 patients. In 68 acute and 21 chronic patients, the total vessel lumen (VL), true lumen, false lumen (FL) and perfused FL area were measured in the innominate, right common carotid and left common carotid artery. Relative luminal changes were compared. RESULTS: In acute aortic dissection, 80% innominate, 40% right carotid and 59% left carotid arteries were dissected preoperatively, but postoperatively FL was only patent in 29%, 12% and 10% (P < 0.001). FL disappearance resulted in >20% total VL reduction in innominate, right carotid and left carotid artery (P < 0.01). In CAD, only 38% innominate, 14% right carotid and 43% left carotid arteries were dissected preoperatively, but postoperatively FL was patent in 19% (ns), 10% (ns) and 5% (P = 0.009). CONCLUSION: Vascular remodelling is frequently found after the island technique. In acute aortic dissection, the island technique frequently initiates FL disappearance associated with VL decrease. Continuously dissected head vessels show positive remodelling with true lumen increase without VL increase. FL disappearance is frequently found in CAD.
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Disección Aórtica , Implantación de Prótesis Vascular , Humanos , Resultado del Tratamiento , Implantación de Prótesis Vascular/métodos , Estudios Retrospectivos , Aorta/cirugíaRESUMEN
Background: The benefits of utilizing internal thoracic arteries (ITAs) in coronary bypass surgery are well-known. However, the safety of this practice in elderly patients needs to be proven. Methods: We studied all patients who are 75 years of age and older, who received at least one ITA graft while undergoing isolated, conventional (median sternotomy) coronary artery bypass graft surgery (CABG) between Jan 1st 2002 and Dec 31st 2020 (19 years). Emergent surgeries were excluded. Propensity score matching was used to reduce the patient selection effect. Study outcomes were 30-days mortality, and two sets of dependent intraoperative parameters and postoperative parameters. Results: A total of 1855 patients undergoing CABG was included, of which 1114 received a single left (s)ITA and 741 received combined left and right (d)ITA grafts. 519 pairs were matched. The decision for sITA or dITA was made individually. Thirty-days mortality was low and similar in both groups (sITA 3.3%; dITA 2.9%, p = 0.859). The incidence of sternal wound healing disorder was higher after dITA (3.3 vs 6.9%; p < 0.011), which had also a longer skin-to-skin operative time (181 vs 205 min; p < 0.0001). Re-thoracotomy rates were similar (4.6 vs 6.2%; p = 0.340). There were no significant differences in other secondary parameters. Conclusions: harvesting both ITAs in elderly patients is safe and feasible. However, it increases the risk of sternal wound healing disorders. Long term benefit still needs to be proven.
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BACKGROUND: Mental distress is suspected to influence the morbidity of cardiac patients. Evaluating mental distress in cardiac patients is rare and the impact on surgical outcome is still not certified. METHODS: In 94 cardiac surgical patients, mental distress was assessed by the Patient Health Questionnaire-4 (PHQ-4). We defined length of stay in hospital and on intensive care unit as well as time of mechanical ventilation as outcomes on surgery. Age, physical activity, diabetes, overweight, PHQ-4, and an inflammation marker were tested for their predictive value on outcomes. RESULTS: Reportedly prevalence of generalized anxiety was 16.0% and depression rate was 13.8%. Length of stay in hospital was 13 ± 8 days, time of mechanical ventilation was 10 (0-1,207) hours, and length of stay on intensive care unit was 3 ± 6 days. Length of stay in hospital was significantly predicted by age (p = 0.048), low physical activity (p = 0.029), and high C-reactive protein (CRP; p = 0.031). Furthermore, CRP was the only significant predictor of time of mechanical ventilation and length of stay on intensive care unit. CONCLUSION: Outcome was not predicted by mental distress. However, inflammation marker CRP was predictive for outcome, potentially caused by higher cardiovascular risk profile. Additionally, depression was referred to be associated with inflammation. Probably, the small sample and the timing of assessment were responsible for the missing relation between mental distress and outcome. We presume a relation with low physical activity and depression. Nevertheless, further randomized studies are needed to pay more attention on patients' distress to intervene preoperatively to improve postoperative outcome.
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This work studied a multistage gasification system that is designed for producing a syngas with a low tar content. The proposed system is an atmospheric bubbling fluidized-bed gasifier and comprises mainly pyrolysis, combustion, and gasification zones. The numerical investigation is performed using Aspen Plus to study Prosopis Juliflora gasification. Chemical reactions as well as tar treatment in the process are investigated. Two different pyrolysis temperatures were considered: 500 and 600 °C, along with three different particle size ranges: 0.2-0.5, 0.5-1, and 1-2 mm. The effect of the air-to-biomass ratio, with values from 0.2 to 1.2, and the gasification reactor temperature, from 800 to 1000 °C, on the composition of product gas and tar species formation during the process (phenol, naphthalene, benzene, and toluene), its lower heating value (LHV), and cold gasification efficiency (CGE) were studied. Results showed that a pyrolysis temperature of 600 °C and a particle size range of 0.2-0.5 mm displayed less tar produced from both combustion and gasification zones and were associated with greater CO, H2, and CH4 yields, compared to the other pyrolysis parameters tested. Increasing the gasification temperature led to increasing the CO, H2, and tar yields and decreasing the CH4 yield and CGE. The maximum CGE combined with the minimum tar amount produced could be obtained with values of 800 °C and 1.2 for the gasification temperature and the air-to-biomass ratio, respectively. The numerical simulation results will be used to improve the performance of the proposed system.
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To analyze whether cardiac surgical residents can perform their first surgeries without compromising patients' safety or outcomes, by comparing their performance and results to those of senior surgeons. All documented CABGs conducted between 2002 and 2020 were included. Surgeries were divided according to the experience level of the main surgeon (defined by the number of CABG conducted by him/her) using the following thresholds: 1000; 150; 80 and 35. This resulted in 5 groups: senior surgeons (the reference group); attending surgeons; fellow surgeons; advanced residents and new residents. Primary endpoint was 30 day mortality. Secondary endpoints included a list of intra and post-operative parameters (including in-hospital complications). A multivariable analysis was conducted. 16,486 CABG were conducted by 66 different surgeons over a period of 18 years. Multivariable analysis did not find significant differences between both the primary and the secondary endpoints. Skin-to-skin time correlated significantly with experience level, as new residents needed almost 30% more time than senior surgeons (234 vs 180 minutes). With a suitable supervision by experienced surgeons, patient selection and sufficient resources (longer duration of surgery), surgical residents can perform CABGs with good results and without compromising the patient's outcome.
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Internado y Residencia , Cirujanos , Humanos , Masculino , Femenino , Competencia Clínica , Resultado del Tratamiento , Cirujanos/educación , Puente de Arteria Coronaria/efectos adversos , Estudios RetrospectivosRESUMEN
Healthcare facilities are facing huge challenges due to the outbreak of COVID-19. Around the world, national healthcare contingency plans have struggled to cope with the population health impact of COVID-19, with healthcare facilities and critical care systems buckling under the extraordinary pressures. COVID-19 has starkly highlighted the lack of reliable operational tools for assessing the level sof flexibility of a hospital building to support strategic and agile decision making. The aim of this study was to modify, improve and test an existing assessment tool for evaluating hospital facilities flexibility and resilience. We followed a five-step process for collecting data by (i) doing a literature review about flexibility principles and strategies, (ii) reviewing healthcare design guidelines, (iii) examining international healthcare facilities case studies, (iv) conducting a critical review and optimization of the existing tool, and (v) assessing the usability of the evaluation tool. The new version of the OFAT framework (Optimized Flexibility Assessment Tool) is composed of nine evaluation parameters and subdivided into measurable variables with scores ranging from 0 to 10. The pilot testing of case studies enabled the assessment and verification the OFAT validity and reliability in support of decision makers in addressing flexibility of hospital design and/or operations. Healthcare buildings need to be designed and built based on principles of flexibility to accommodate current healthcare operations, adapting to time-sensitive physical transformations and responding to contemporary and future public health emergencies.