Intraperitoneal drain placement and outcomes after elective colorectal surgery: international matched, prospective, cohort study

Despite current guidelines, intraperitoneal drain placement after elective colorectal surgery remains widespread. Drains were not associated with earlier detection of intraperitoneal collections, but were associated with prolonged hospital stay and increased risk of surgical-site infections.Background Many surgeons routinely place intraperitoneal drains after elective colorectal surgery. However, enhanced recovery after surgery guidelines recommend against their routine use owing to a lack of clear clinical benefit. This study aimed to describe international variation in intraperitoneal drain placement and the safety of this practice. Methods COMPASS (COMPlicAted intra-abdominal collectionS after colorectal Surgery) was a prospective, international, cohort study which enrolled consecutive adults undergoing elective colorectal surgery (February to March 2020). The primary outcome was the rate of intraperitoneal drain placement. Secondary outcomes included: rate and time to diagnosis of postoperative intraperitoneal collections; rate of surgical site infections (SSIs); time to discharge; and 30-day major postoperative complications (Clavien-Dindo grade at least III). After propensity score matching, multivariable logistic regression and Cox proportional hazards regression were used to estimate the independent association of the secondary outcomes with drain placement. Results Overall, 1805 patients from 22 countries were included (798 women, 44.2 per cent; median age 67.0 years). The drain insertion rate was 51.9 per cent (937 patients). After matching, drains were not associated with reduced rates (odds ratio (OR) 1.33, 95 per cent c.i. 0.79 to 2.23; P = 0.287) or earlier detection (hazard ratio (HR) 0.87, 0.33 to 2.31; P = 0.780) of collections. Although not associated with worse major postoperative complications (OR 1.09, 0.68 to 1.75; P = 0.709), drains were associated with delayed hospital discharge (HR 0.58, 0.52 to 0.66; P < 0.001) and an increased risk of SSIs (OR 2.47, 1.50 to 4.05; P < 0.001). Conclusion Intraperitoneal drain placement after elective colorectal surgery is not associated with earlier detection of postoperative collections, but prolongs hospital stay and increases SSI risk

Sensor application of quinoxaline based conducting polymers

Creative new design and development strategies led to interesting new materials and enhanced performance in certain devices. The ability of molecular designers in understanding how to gain control over the structure in polythiophenes makes the synthesis of polythiophenes a critical subject in the development of new advanced materials. The study of redox-active receptor molecules, in which a change in the electrochemical behaviour of a signaling redox unit is used to monitor the complexation of neutral or ionic guest species, is an increasingly important area of supramolecular chemistry. This type of molecular and ion recognition sensor is based on a host-guest arrangement involving the receptor molecule and the analyte. The application of this mechanism to thin solid films is particularly relevant for the construction of sensor devices. In this context, the use of conjugated polymers is an important area of research and considerable efforts have been directed towards the use of versatile polythiophene derivatives. In this work, we report the synthesis and characterization of:5,12-dihydrothieno [3’,4’:2,3][1,4]dioxocino[6,7-b]quinoxaline (Q1) and the interaction and electrochemical recognition of silver and mercury cations with electropolymerised P(Q1) films (Fig.1)

Synthesis and electropolymerization of 5,12-dihydrothieno[3′,4′:2,3][1,4]dioxocino[6,7-b]quinoxaline and its electrochromic properties

Synthesis of a new thiophene-based monomer; 5,12-dihydrothieno[3′,4′:2,3][1,4]dioxocino[6,7-b]quinoxaline (DDQ), was realized. The chemical structure of the monomer was characterized by 1H NMR, FTIR and mass spectroscopy techniques. Electrochemical polymerization of DDQ and characterization of the resulting polymer [P(DDQ)] was performed. Moreover, the spectroelectrochemical and electrochromic properties of the polymer film were investigated. P(DDQ) has a low oxidation potential (0.9 V) and low band gap (1.73 eV) compared to polythiophene. In addition, dual-type polymer electrochromic device (ECD) based on P(DDQ) with poly(3,4-ethylenedioxythiophene) (PEDOT) was constructed. Spectroelectrochemistry, electrochromic switching, stability and open-circuit stability of the device were studied. It was observed that polymer have good switching time, reasonable contrast and optical memory

and electrochromic device application

A new thiophene-based monomer; 1,2-bis(thiophen-3-ylmethoxy)benzene (BTMB) has been synthesized and chemical structure of the monomer was characterized. Polymerization of BTMB and characterization of the resulting polymer P(BTMB) were performed. Spectroelectrochemical analysis of the P (BTMB) reflected electronic transitions at 400 nm, 520 nm and similar to 720 nm, corresponding to pi-pi* transition, polaron and bipolaron band formation respectively. Switching ability was evaluated by a kinetic study via measuring the transmittance (%T) at the maximum contrast. Dual type all polymer electrochromic device (ECD) based on P(BTMB) and poly(ethylene dioxythiophene) (PEDOT) was constructed. Spectroelectrochemistry and switching ability of the devices were investigated by UV-vis spectroscopy. (C) 2010 Elsevier Masson SAS. All rights reserved

polymer

We synthesized a new electroactive pyrrole functionalized monomer; 2-butyl-5,12-dihydro-2H-pyrrolo[3',4':2,3][1,4]dioxocino[6,7-b]quinoxaline (BuDQP) where beta-positions of the pyrrole ring are blocked. With the help of this strategy, formation of alpha-beta linkages during polymerization was prevented, resulting in a more regiochemically defined material. Characterization of newly synthesized compounds was performed by FTIR, GC-MS,H-1 NMR,C-13 NMR techniques and elemental analysis. Polymerization and copolymerization of BuDQP and characterization of the resulting polymers were also performed. Spectroelectrochemical investigations, switching abilities, colorimetry studies and stability experiments were performed on both for polymer and copolymer. Spectroelectrochemical analysis of P(BuDQP) reflected electronic transitions at 328 nm (pi-pi* transition) and 500 nm (polaron bands) with an electronic band gap of 2.30 eV, while copolymer (P(BuDQP-co-Py)) revealed electronic transitions at 346 nm (pi-pi* transition) and 518 nm (polaron bands) with an electronic band gap of 2.24 eV. Colorimetry studies revealed that P(BuDQP) has only two colors (blue and yellow) whereas copolymer film has six different colors in its oxidized and neutral states. (C) 2014 Elsevier B.V. All rights reserved

Synthesis and electropolymerization of 3,4-substituted quinoxaline functionalized pyrrole monomer and optoelectronic properties of its polymer

We synthesized a new electroactive pyrrole functionalized monomer; 2-butyl-5,12-dihydro-2H-pyrrolo[3′,4′:2,3][1,4]dioxocino[6,7-b] quinoxaline (BuDQP) where β-positions of the pyrrole ring are blocked. With the help of this strategy, formation of α-β linkages during polymerization was prevented, resulting in a more regiochemically defined material. Characterization of newly synthesized compounds was performed by FTIR, GC-MS, 1H NMR, 13C NMR techniques and elemental analysis. Polymerization and copolymerization of BuDQP and characterization of the resulting polymers were also performed. Spectroelectrochemical investigations, switching abilities, colorimetry studies and stability experiments were performed on both for polymer and copolymer. Spectroelectrochemical analysis of P(BuDQP) reflected electronic transitions at 328 nm (π-π* transition) and 500 nm (polaron bands) with an electronic band gap of 2.30 eV, while copolymer (P(BuDQP-co-Py)) revealed electronic transitions at 346 nm (π-π* transition) and 518 nm (polaron bands) with an electronic band gap of 2.24 eV. Colorimetry studies revealed that P(BuDQP) has only two colors (blue and yellow) whereas copolymer film has six different colors in its oxidized and neutral state

Preparation of an EDOT-based polymer: optoelectronic properties and electrochromic device application

Here we present the synthesis, characterization and electropolymerization of a new EDOT-based monomer; 5,10-dihydrobenzo[f]thieno[3,4-b][1,4]dioxocine (DTD). Electrochemical polymerization of DTD was performed potentiostatically by using dichloromethane (DCM) as solvent and tetrabutylammonium hexafluorophosphate (TBPF 6 ) as supporting electrolyte. Homopolymer [P(DTD)] films and copolymer [P(DTD-co-TPA)] films of DTD prepared by using 4-(2,5-di(thiophen-2-yl)-1H-pyrrole-1-yl)butane-1-amine (TPA) were characterized via CV and UV-vis spectroscopy. Spectroelectrochemical analysis of P(DTD) revealed electronic transitions at 585 nm (π-π∗ transition) with an electronic band gap of 1.69 eV. Electrochromic studies revealed that P(DTD) has competitive properties to EDOT. Furthermore, a dual-type complementary colored polymer electrochromic device based on P(DTD) and P(TPA) was constructed in sandwich configuration. Spectroelectrochemical studies revealed that the oxidized state of the device shows a blue color whereas it is yellow in the reduced state. The maximum contrast (Δ%T) and switching time of the device were measured as 25.5% and 0.5 s for 385 nm and 21% and 1.0 s for 550 nm

electrochromic device application

Here we present the synthesis, characterization and electropolymerization of a new EDOT-based monomer; 5,10-dihydrobenzo[f] thieno[3,4-b][1,4] dioxocine (DTD). Electrochemical polymerization of DTD was performed potentiostatically by using dichloromethane (DCM) as solvent and tetrabutylammonium hexafluorophosphate (TBPF6) as supporting electrolyte. Homopolymer [P(DTD)] films and copolymer [P(DTD-co-TPA)] films of DTD prepared by using 4-(2,5-di(thiophen-2-yl)-1Hpyrrole- 1-yl) butane-1-amine (TPA) were characterized via CV and UV-vis spectroscopy. Spectroelectrochemical analysis of P(DTD) revealed electronic transitions at 585 nm (pi-pi* transition) with an electronic band gap of 1.69 eV. Electrochromic studies revealed that P(DTD) has competitive properties to EDOT. Furthermore, a dual-type complementary colored polymer electrochromic device based on P(DTD) and P(TPA) was constructed in sandwich configuration. Spectroelectrochemical studies revealed that the oxidized state of the device shows a blue color whereas it is yellow in the reduced state. The maximum contrast (Delta% T) and switching time of the device were measured as 25.5% and 0.5 s for 385 nm and 21% and 1.0 s for 550 nm

Production and performance of triploid rainbow trout in Turkey

WOS: 00023365820001

Electrochromic Properties

This research highlights the degree of conformity between our electrochemical and theoretical studies conducted on the newly designed electropolymerizable monomers (BuDOP, BenDOP and BenzoDOP) possessing 3,4-alkylenedioxypyrrole (ADOP) backbone (BuDOP). We tried to select logical enhancing of the structures in a stepwise in order to discuss the effects of benzene (BenDOP) and benzodioxane (BenzoDOP) like aromatic subunits to the electrochromic properties of the target monomers. Following to the completion of the synthetic steps, appropriate structural analyses of monomers were performed (FT-IR, GC-MS, H-1-NMR, C-13-NMR). Subsequently, their corresponding polymers were prepared by electrochemical oxidation and characterized. Afterwards, our consecutive efforts have been contributed to theoretical studies in order to obtain information about their structural properties. To this aim, geometry optimizations were carried out using hybrid density functional theory (DFT/B3LYP/LANL2DZ) and HOMO, LUMO energy levels, HOMO-LUMO energy gaps (Delta E), electron affinity (EA) as well as ionization potential (IP) values were calculated. Theoretical data were then used for identifying the structure-electronic properties relationship and we aimed to determine the electrochromic properties of the studied monomers. Our results from the B3LYP/LANL2DZ calculations indicated that P(BenDOP) has the lowest HOMO-LUMO gap and we predicted that theoretical data were in good agreement with the experimental studies. (C) 2016 The Electrochemical Society. All rights reserved