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Imidacloprid, the most used systemic insecticide, is suspected of having harmful effects on honeybees at nanogram per bee or at microgram per kilogram levels. However, there is a lack of methodology to detect imidacloprid and its metabolites at such low levels. We developed a method for the determination of low amounts of imidacloprid in soils, plants (leaves and flowers), and pollens by using HPLC coupled to tandem mass spectrometry (APCI-MS/MS). Extraction, separation, and detection were performed according to quality assurance criteria, to Good Laboratory Practice, and to criteria from the directive 96/23/EC, which is designed for banned substances. The linear range of application is 0.5-20 [micro]g/ kg imidacloprid in soils, in plants, and in pollens, with a relative standard deviation of 2.9% at 1 [micro]g/kg. The limits of detection and of quantification are LOD = 0.1 [micro]g/kg and LOQ = 1 [micro]g/kg, respectively. For the first time, this study permitted us to follow the fate of imidacloprid in the environment. When treated, flowers of sunflower and maize contain average values of ~10 [micro]g/kg imidacloprid. This explains that pollens from these crops are contaminated at levels of a few micrograms per kilogram, suggesting probable deleterious effects on honeybees.

Introduction: The management of out-of-hospital traumatic cardiac arrest (TCA) for professional rescuers entails Advanced Life Support (ALS) with specific actions to treat the potential reversible causes of the arrest: hypovolemia, hypoxemia, tension pneumothorax (TPx), and tamponade. The aim of this study was to assess the impact of specific rescue measures on short-term outcomes in the context of resuscitating patients with a TCA., Methods: This retrospective study concerns all TCA patients treated in two emergency medical units, which are part of the Northern French Alps Emergency Network (RENAU), from January 2004 through December 2017. Utstein variables and specific rescue measures in TCA were compiled: fluid expansion, pelvic stabilization, tourniquet application, bilateral thoracostomy, and thoracotomy procedures. The primary endpoint was survival rate at Day 30 with good neurological status (Cerebral Performance Category [CPC] score CPC 1 and CPC 2)., Results: In total, 287 resuscitation attempts in TCA were included and 279 specific interventions were identified: 262 fluid expansions, 41 pelvic stabilizations, five tourniquets, and 175 bilateral thoracostomies (including 44 with TPx)., Conclusion: Among the standard resuscitation measures to treat the reversible causes of cardiac arrest, this study found that bilateral thoracostomy and tourniquet application on a limb hemorrhage improve survival in TCA. A larger sample for pelvic stabilization is needed.

Aim: To compare the safety, pharmacokinetics and pharmacodynamics of ADO09 with insulin lispro (Lispro) and separate subcutaneous injections of human insulin and pramlintide (Ins&Pram) in 24 subjects with type 1 diabetes., Methods: At three dosing visits, participants received single doses of ADO09, Ins&Pram or Lispro immediately before eating a standardized mixed meal together with 1 g of acetaminophen, which was used as a surrogate marker to evaluate the kinetics of gastric emptying. Premeal blood glucose was adjusted to 126 mg/dL ± 10% by means of insulin and glucose infusions. The insulin dose was 7.5 U and the pramlintide dose was 45 μg. Blood glucose, glucagon and acetaminophen concentrations were assessed as pharmacodynamic endpoints; insulin and pramlintide concentrations were analysed as pharmacokinetic endpoints, and safety and tolerability were assessed., Results: Compared with Lispro, ADO09 reduced postprandial blood glucose (ppBG) excursions by more than 95% in the first hour postmeal (mean ± SD ∆AUC BG 0-1 h: 1.4 ± 9.9 mg*h/dL vs. 43.5 ± 15.3 mg*h/dL; p < .0001). Maximum ppBG was significantly improved with ADO09 (∆BGmax 87.0 ± 35.5 mg/dL) versus both Lispro (109.2 ± 31.1 mg/dL; p = .0133) and Ins&Pram (109.4 ± 44.3 mg/dL; p = .0357). Gastric emptying with ADO09 was similar to Ins&Pram and significantly slower than with Lispro. All treatments were well tolerated and both adverse events and hypoglycaemic events were rare during the meal test procedure., Conclusion: ADO09 was well tolerated and markedly reduced ppBG compared with Lispro. ADO09 formulation was generally similar to the separate administration of insulin and pramlintide, except for a better BG level in the 4-8 h interval postmeal. These positive results warrant further investigations with ADO09., (© 2020 John Wiley & Sons Ltd.)

Amphiphilic zinc porphyrin (P(Zn); electron donor, D)-fullerene (C(60); electron acceptor, A) dyads 2 and 3, bearing an identical hydrophilic wedge with triethylene glycol chains but different linkers between the P(Zn) and C(60) units, self-assemble into nanotubes with essentially different dimensional and geometrical features from one another. The nanotube from dyad 2 with an ester linker consists of a bilayer wall formed with coaxially segregated D and A nanodomains along the tube axis (coaxial D-A heterojunction), thereby displaying explicit photoconductivity with ambipolar carrier transport properties. In contrast, the nanotube from dyad 3 with a rigid arylacetylene linker consists of a monolayer wall with an alternate geometry of D/A stacking, resulting in poor photoconducting outputs. Such a geometrical difference also significantly affects the photovoltaic properties.

An α-[Cu(II)-porphyrin]-polyethylene was synthesized for the first time using copper catalyzed 1,3-dipolar azide-alkyne Huisgen cycloaddition yielding highly colored moiety-substituted polyethylene., (This journal is © The Royal Society of Chemistry 2011)

Unidirectionally aligned photoconductive donor-acceptor heterojunction molecular wires spanning over fifty square microns are fabricated using the Langmuir-Blodgett technique., (This journal is © The Royal Society of Chemistry 2011)

Self-assembly and reassembly of high aspect ratio nanowires of trigeminal porphyrins and their manipulation using an atomic force microscope (AFM) is reported.

Presence of strongly binding anion, F(-) stabilizes the photo-induced charge-separated states of a bis-fullerene-substituted oxoporphyrinogen due to the large shift in the oxidation potential of the oxoporphyrinogen moiety upon anion binding through hydrogen bonding at its core.

Upon slow admission of MeOH, the enantiomerically pure form of chiral amphiphilic porphyrin-fullerene dyad 1 in CH(2)Cl(2) self-assembles at 25 degrees C into nanofibers with a built-in donor/acceptor heterojunction, while its racemic form, under identical conditions, self-assembles into submicrometer-sized spheres with a donor/acceptor arrangement essentially different from that in the nanofiber assembly. Although a cast film of the latter hardly shows a photoconducting profile on micrometer-gap electrodes, the former sample clearly displays photoconduction with an ambipolar charge-transporting character. The electron and hole mobilities under zero electric field, as estimated from time-of-flight profiles, are 0.14 and 0.10 cm(2) V(-1) s(-1), respectively, which are comparable to or even better than those reported for top-class organic materials with a donor/acceptor heterojunction.

Development of materials for efficient photoenergy conversion is a subject of critical importance in current science and technology. Efficient performance requires well-controlled segregation of electron donor and acceptor moieties, which we have achieved using block copolymers of tetraphenylporphinatozinc(II) (donor) and C(60) fullerene (acceptor) using living ring-opening metathesis polymerization (ROMP). The resulting amphiphilic ROMP block copolymers undergo self-assembly into nanostructured phase-segregated 1-dimensional nanowires with an approximately 5.5 nm periodicity zebra-stripe-like morphology simply by drop-casting solutions of the polymers onto a substrate such as mica or highly oriented pyrolytic graphite (HOPG). Thin films of the self-assembled nanophase-segregated copolymers exhibit high charge carrier mobilities (approximately 0.26 cm(2) V(-1) s(-1)) and electrical conductivities (up to 6.4 x 10(-4) cm(2) V(-1) s(-1)) as well as highly repeatable photocurrent switching with rapid ON/OFF responses upon white light irradiation.

The controlled fabrication of nanometer-scale objects is without doubt one of the central issues in current science and technology. However, existing fabrication techniques suffer from several disadvantages including size-restrictions and a general paucity of applicable materials. Because of this, the development of alternative approaches based on supramolecular self-assembly processes is anticipated as a breakthrough methodology. This review article aims to comprehensively summarize the salient aspects of self-assembly through the introduction of the recent challenges and breakthroughs in three categories: (i) types of self-assembly in bulk media; (ii) types of components for self-assembly in bulk media; and (iii) self-assembly at interfaces.

One of the most important outcomes of organic nanotechnologies could be development of well-integrated systems for sensing of particular chemical species. Use of color indicators is an attractive approach to guest reporting. Of the known chromophores, porphyrin and its derivatives are the most widely studied functional chromophores in a diverse range of research fields. In this review, recent developments in colorimetric indicator functions of porphyrin derivatives and related compounds in their molecular and nano-architectures are reviewed according to the classification: (i) rather simple porphyrin derivatives, (ii) porphyrin conjugates, (iii) porphyrins embedded in bulk materials, and (iv) porphyrins in organized films. Porphyrin derivatives with unusual structures, such as expanded and N-confused ones have been used for color indicators in specific cases. Electron and energy transfers in porphyrins conjugated with other functional moieties resulted in dynamic sensing systems including switch-on and switch-off actions. Immobilization of porphyrin color indicators in appropriate matrices is important for practical applications. Use of supramolecular films such as self-assembled monolayers, Langmuir-Blodgett films, and layer-by-layer assemblies as porphyrin nanoarchitectures often offers opportunities for colorimetric outputs based on control of their aggregate structures.

The ruthenium complex bis-tetrabutylammonium cis-dithiocyanato-N,N'-bis-2,2'-bipyridine-4-carboxylic acid, 4'-carboxylate ruthenium(II), N-719, was found to block the dark current of dye sensitized solar cells (DSC), based on mesoporous TiO2 films deposited on a F-doped tin oxide electrode and the effect was compared to surface treatment by TiCl4 and the introduction of a compact TiO2 blocking layer.

An amphiphilic zinc porphyrin-fullerene dyad appended with triethyleneglycol chains in aqueous media forms uniformly-sized multilamellar vesicles with a mean diameter of 100 nm that are thermally stable and robust against membrane lysis with surfactants.

Imidacloprid, a new systemic insecticide used as seed-dressing, has been widely used in France since 1994. Its application mode and its efficiency allow a significant reduction in comparison with the usual quantity of chemicals used during pulverising treatment. But the insecticide imidacloprid is suspected to have harmful effects on the pollinators as many bees have died since its introduction. Recent studies have shown that imidacloprid has chronic and sub-lethal toxicities at levels of micro g/kg or less. It was therefore necessary to detect imidacloprid at these levels in soils, plants, flowers, and pollens. With this aim, we characterised the bio-availability of imidacloprid in the environment using a new quantitative analytical method, as a basis for the evaluation of the risk for bees.