21 research outputs found
Influence of the conditions of sensitization on the characteristics of p-DSCs sensitized with asymmetric squaraines
The effect of the conditions of sensitization on the photoelectrochemical performance of p-type dye-sensitized solar cells (p-DSCs)
with screen-printed nickel oxide (NiO) photocathodes is analyzed. The dye-sensitizers employed in the present study are asymmetric
squaraines. The conditions of sensitization differ for the relative concentration of the anti-aggregating agentCDCA(chenideoxycholic
acid) with respect to the concentration of the dye-sensitizer. The co-adsorption of CDCA onto NiO electrode brings about a decrease
in the surface concentration of the anchored dye as well as a blueshift of the characteristic wavelengths of optical absorption of
the asymmetric squaraines considered here. Beside this, the employment of CDCA as co-adsorbent reduces the overall conversion
performance of the resulting squaraine-sensitized p-DSCs with consequent diminution of the short-circuit current density. This result
is ascribed to the acid action of CDCA toward the amminic nitrogen of the squaraines. Quantum efficiency spectra show that CDCA
acts as a quencher of the intrinsic photoelectrochemical activity of NiO. Moreover, CDCA does not interfere with the mechanism of
charge injection effectuated by the photoexcited squaraines. The photoelectrochemical impedance spectra was analyzed employing
a model of equivalent circuit developed for semiconducting nanostructure electrodes
Il monitoraggio dei movimenti e delle deformazioni con tecniche geomatiche di basso costo
L’osservazione dell’evoluzione di fenomeni di dissesto ha una importanza strategica sul nostro territorio. Un importante precursore di fenomeni franosi è il movimento o la deformazione degli stessi: tali parametri possono essere osservati con tecniche geomatiche. Le misure topografiche o GNSS con ricevitori geodetici (multi-frequenza e multi-costellazione) sono ormai ben consolidate nel trattamento e nella precisione. La realizzazione di sistemi basati su questi sensori non è tuttavia a basso costo, specie se consideriamo tecniche GNSS applicate su molti punti di controllo per una descrizione dettagliata del fenomeno, o installazioni soggette a pericoli oggettivi e dunque da considerarsi praticamente “a perdere”. Ricevitori GNSS singola frequenza sono oggi reperibili a costi minori di cento euro e possono, sotto opportune ipotesi e ingegnerizzazioni, costituire alternative ai ricevitori geodetici. Nell’ambito di un progetto di ricerca finanziato da CSI Piemonte per lo studio di tecnologie di monitoraggio a basso costo, sono stati sviluppati sistemi di acquisizione, trasmissione ed elaborazione dati basati su sensori GNSS singola frequenza di minuscole dimensioni. Il sistema costituisce una sorta di piccola stazione permanente GNSS, integrata con accelerometri per la stima di inclinazione e vibrazioni e con sensori meteorologici. È corredata di micro PC con processore ARM e interfacce di comunicazione wireless a lungo raggio per la trasmissione in tempo reale delle misure. Il sistema risulta caratterizzato da consumi elettrici molto contenuti ed è di rapida installazione in siti anche complessi dal punto di vista dell’accesso, dell’alimentazione e comunicazione. Vengono esposti nella nota i risultati delle prove di accuratezza dei sensori GNSS eseguite in laboratorio, le procedure di calibrazione dei sensori e la loro ingegnerizzazione, oltre ai primi risultati sulle installazioni situate nel nord del Piemonte su alcune zone di dissesto
Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries
Abstract
Background
Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres.
Methods
This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries.
Results
In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia.
Conclusion
This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
L’échocardiographie transœsophagienne dans la conduite du pontage auriculo-fémoral pendant la réparation d’un anévrysme de l’aorte thoraco-abdominale : une observation
Dysfonction diastolique aiguë pendant ľopération ďun anévrysme aortique thoracoabdominal
Acute diastolic dysfunction: a new entity recognized by transesophageal echocardiography in thoraco-abdominal aortic aneurysm surgery
The impact of the histological classification of ampullary carcinomas on long-term outcomes after pancreaticoduodenectomy: a single tertiary referral center evaluation
Purpose Ampullary carcinomas (ACs) are classified as pancreatobiliary (Pb-AC), intestinal (Int-AC), or mixed (Mixed-AC). The influencing role of AC subtypes on long-term outcomes is still matter of debate. Aim of this study is to evaluate the prognostic role of the three histological variants on the overall (OS) and disease-free survival (DFS) after pancreaticoduodenectomy(PD). Methods All PDs for AC between 2004 and 2020 were included. Patients were classified according to the histological feature in Pb-AC, Int-AC, and Mixed-AC. Five-year OS and DFS were compared among the subtypes. Additionally, the prognostic role of the histological classification on OS and DFS was evaluated. Results Fifty-six (48.7%) Pb-ACs, 53 (46.1%) Int-ACs, and 6 (5.2%) Mixed-ACs were evaluated. A poorer 5-year OS was evidenced for the Pb-AC group (54.1%) as compared to the Int-AC cohort (80.7%) (p = 0.03), but similar to the Mixed-AC population (33%) (p = 0.45). Pb-AC presented a worse 5-year DFS (42.3%) in comparison to the Int-AC (74.8%) (p = 0.002), while no difference was evidenced in comparison to the Mixed-AC (16.7%) (p = 0.51). At the multivariate analysis, the Pb-/Mixed-AC histotype was recognized as negative prognostic factor for both OS (OR: 2.29, CI: 1.05-4.98; p = 0.04) and DFS (OR: 2.17, CI: 1-4.33; p = 0.02). Conclusion Histological subtypes of AC play a relevant role in long-term outcomes after PD. Pb-ACs and Mixed-ACs show a more aggressive tumor biology and a consequent worse survival as compared to the Int-AC subtype
Single-Docking Full Robotic Surgery for Rectal Cancer: A Single-Center Experience
Purpose. Robotic surgery has gradually gained importance in the treatment of rectal cancer. However, recent studies have not shown any advantages when compared with laparoscopy. The objective of this study is to report a single surgeon\u2019s experience in robotic rectal surgery focusing on short-term and long-term outcomes. Methods. Sixty consecutive robotic rectal resections for adenocarcinoma, over a 4-year period, were retrospectively reviewed. Patients\u2019 characteristics and perioperative outcomes were analyzed. Oncological outcomes and surgical resection quality as well as overall and disease-free survival were also assessed. Results. Thirty patients out of 60 (50%) underwent neoadjuvant therapy. Anterior rectal resection was performed in 52 cases (86.7%), and abdominoperineal resection was done in 8 cases (13.3%). Mean operative time was 283 (\ub168.6) minutes. The conversion rate was 5% (3 patients). Postoperative complications occurred in 10 cases (16.7%), and reoperation was required in 1 case (1.7%). Mean hospital stay was 9 days, while 30-day mortality was 1.7% (1 patients). The histopathological analysis reported a negative circumferential radial margin and distal margins in 100% of cases with a complete or near complete total mesorectal excision in 98.3% of patients. Mean follow-up was 32.8 months with a recurrence rate of 3.4% (2 patients). Overall survival and disease-free survival were 94% and 87%, respectively. Conclusions. Robotic surgery for rectal cancer proves to be safe and feasible when performed by highly skilled surgeons. It offers acceptable perioperative outcomes with a conversion rate notably lower than with the laparoscopic approach. Adequate pathological results and long-term oncological outcomes were also obtained