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Conjugated polymers with glycol-based chains, are emerging as a material class with promising applications as organic mixed ionic-electronic conductors, particularly in bioelectronics and thermoelectrics. However, little is still known about their microstructure and the role of the side chains in determining intermolecular interactions and polymer packing. Here, we use the combination of electrospray deposition and scanning tunneling microscopy to determine the microstructure of prototypical glycolated conjugated polymers (pgBTTT and p(g2T-TT)) with submonomer resolution. Molecular dynamics simulations of the same surface-adsorbed polymers exhibit an excellent agreement with the experimental images, allowing us to extend the characterization of the polymers to the atomic scale. Our results prove that, similarly to their alkylated counterparts, glycolated polymers assemble through interdigitation of their side chains, although significant differences are found in their conformation and interaction patterns. A model is proposed that identifies the driving force for the polymer assembly in the tendency of the side chains to adopt the conformation of their free analogues, i.e., polyethylene and polyethylene glycol, for alkyl or ethylene glycol side chains, respectively. For both classes of polymers, it is also demonstrated that the backbone conformation is determined to a higher degree by the interaction between the side chains rather than by the backbone torsional potential energy. The generalization of these findings from two-dimensional (2D) monolayers to three-dimensional thin films is discussed, together with the opportunity to use this type of 2D study to gain so far inaccessible, subnm-scale information on the microstructure of conjugated polymers.

Uncommon metal oxidation states in porphyrinoid cofactors are responsible for the activity of many enzymes. The F₄₃₀ and P450nor co-factors, with their reduced NiI- and FeIII-containing tetrapyrrolic cores, are prototypical examples of biological systems involved in methane formation and in the reduction of nitric oxide, respectively. Herein, using a comprehensive range of experimental and theoretical methods, we raise evidence that nickel tetraphenyl porphyrins deposited in vacuo on a copper surface are reactive towards nitric oxide disproportionation at room temperature. The interpretation of the measurements is far from being straightforward due to the high reactivity of the different nitrogen oxides species (eventually present in the residual gas background) and of the possible reaction intermediates. The picture is detailed in order to disentangle the challenging complexity of the system, where even a small fraction of contamination can change the scenario.

The development, optimization, and assessment of new methods for the preparation of conjugated materials is key to the continued progress of organic electronics. Direct C–H activation methods have emerged and developed over the last 10 years to become an invaluable synthetic tool for the preparation of conjugated polymers for both redox-active and solid-state applications. Here, we evaluate direct (hetero)arylation polymerization (DHAP) methods for the synthesis of indaceno[1,2-b:5,6-b′]dithiophene-based polymers. We demonstrate, using a range of techniques, including direct visualization of individual polymer chains via high-resolution scanning tunneling microscopy, that DHAP can produce polymers with a high degree of regularity and purity that subsequently perform in organic thin-film transistors comparably to those made by other cross-coupling polymerizations that require increased synthetic complexity. Ultimately, this work results in an improved atom economy by reducing the number of synthetic steps to access high-performance molecular and polymeric materials.

Novel p-type semiconducting polymers that can facilitate ion penetration, and operate in accumulation mode are much desired in bioelectronics. Glycol side chains have proven to be an efficient method to increase bulk electrochemical doping and optimize aqueous swelling. One early polymer which exemplifies these design approaches was p(g2T-TT), employing a bithiophene-co-thienothiophene backbone with glycol side chains in the 3,3' positions of the bithiophene repeat unit. In this paper, the analogous regioisomeric polymer, namely pgBTTT, was synthesized by relocating the glycol side chains position on the bithiophene unit of p(g2T-TT) from the 3,3' to the 4,4' positions and compared with the original p(g2T-TT). By changing the regio-positioning of the side chains, the planarizing effects of the S-O interactions were redistributed along the backbone, and the influence on the polymer's microstructure organization was investigated using grazing-incidence wide-angle X-ray scattering (GIWAXS) measurements. The newly designed pgBTTT exhibited lower backbone disorder, closer π-stacking, and higher scattering intensity in both the in-plane and out-of-plane GIWAXS measurements. The effect of the improved planarity of pgBTTT manifested as higher hole mobility (μ) of 3.44 ± 0.13 cm2 V-1 s-1. Scanning tunneling microscopy (STM) was in agreement with the GIWAXS measurements and demonstrated, for the first time, that glycol side chains can also facilitate intermolecular interdigitation analogous to that of pBTTT. Electrochemical quartz crystal microbalance with dissipation of energy (eQCM-D) measurements revealed that pgBTTT maintains a more rigid structure than p(g2T-TT) during doping, minimizing molecular packing disruption and maintaining higher hole mobility in operation mode.

The 2D self-assembly of Ni-containing tetrapyrroles on Cu(100) allows control of the Ni atom oxidation state, yielding inactive Ni(II) or active Ni(I) upon modification of the molecule-substrate interaction, resembling the behavior of the biochemical counterpart. Ni(I) is indeed the active site of methanogenic bacteria in the tetrahydrocorphin of the F-430 coenzyme of methyl-coenzyme reductase. Tuning of the electronic configuration of the Ni atom in the 2D system is accomplished by exploiting the surface trans effect, by analogy to the biologic enzymatic pocket, which is activated by a molecular trans effect. In this report, we identify the vibrational fingerprint of the molecular macrocycle that reflects the actual Ni oxidation state in the 2D system showing that, despite the apparent differences of the two cases, the fact that the Ni-porphin in the F-430 pocket is accessible to the reactants but not to the solvent makes the two situations more similar than expected.

Many applications of molecular layers deposited on metal surfaces, ranging from single-atom catalysis to on-surface magnetochemistry and biosensing, rely on the use of thermal cycles to regenerate the pristine properties of the system. Thus, understanding the microscopic origin behind the thermal stability of organic/metal interfaces is fundamental for engineering reliable organic-based devices. Here, we study nickel porphyrin molecules on a copper surface as an archetypal system containing a metal center whose oxidation state can be controlled through the interaction with the metal substrate. We demonstrate that the strong molecule-surface interaction, followed by charge transfer at the interface, plays a fundamental role in the thermal stability of the layer by rigidly anchoring the porphyrin to the substrate. Upon thermal treatment, the molecules undergo an irreversible transition at 420 K, which is associated with an increase of the charge transfer from the substrate, mostly localized on the phenyl substituents, and a downward tilting of the latters without any chemical modification. This journal is

Due to epidemiological and social changes related to the increase in the average life expectancy, hospital users are characterized by elderly chronic and comorbid patients who require recurrent hospitalizations often with disability outcomes. In this framework, an innovative clinical and management hospitalization model is the adequate answer to systematically promote the patient independence. Main features are interdisciplinary and integrated care pathways facing both disease and disability biologically and functionally diagnosed by ICD and ICF. The definition, personalization of pathways/protocols and outcome evaluation represent the foundations of this new model for patient care. The digitalization of hospital clinical data and medical knowledge make the model feasible and fitting the recent WHO guideline: recommendations on digital interventions for health system strengthening.A causa dei cambiamenti epidemiologici e della società legati all’aumento della aspettativa di vita i pazienti che afferiscono in ospedale sono generalmente più anziani, cronici e comorbidi e richiedono frequenti re-ospedalizzazioni spesso con esiti disabilitanti. In questo contesto un nuovo modello di ospedalizzazione innovativo sia dal punto di vista clinico che di management sembra essere la risposta adeguata per promuovere sistematicamente l’autonomia del paziente. Caratteristiche principali del modello sono l’interdisciplinarietà e percorsi di cura integrati che affrontino la malattia e la disabilità valutate con le classificazioni ICD e ICF. Le basi fondanti di questo nuovo modello di cura sono la definizione e la personalizzazione dei percorsi diagnostico terapeutici assistenziali (PDTA). La digitalizzazione dei dati clinici ospedalieri ricavati dai percorsi/protocolli rendono fattibile il modello e si allineano con le recenti line guida dell’OMS sulla digitalizzazione degli interventi nel rafforzare i sistemi sanitari.

Childhood obesity has been described as the main health-related problem in developed countries, due to its link with physical, social and psychological consequences with an increased risk for developing metabolic and cardiovascular diseases in adulthood. All the pupils of both sexes attending the second year of all the primary schools in Pavia, Northern Italy, were recruited (n=470) for this study. Measurements of weight, height and waist circumference (WC) were taken under standard conditions. Body Mass Index (BMI) and waist-to-height-ratio (W/HtR) were computed and sex specific percentile values for BMI, WC and W/HtR were calculated and compared with the same percentiles available for different countries. The results show that according to Cole's cut-off point reference standards, 12.5% and 9.0% of boys and girls respectively are over - weight, 4.7% and 5.2% respectively are obese. The WC mean value is equal to 60.0 ± 6.0 cm in boys and 59.0 ± 6.7 cm in girls. Using dif - ferent 90 th reference worldwide standard percentiles for WC as a comparison, the prevalence of our children with WC > 90 th percentile is very different. The W/HtR mean value of the total sample is 0.46 ± 0.03. Assuming a cutoff of 0.5, 87.6% of the pupils have a W/HtR value ≤ 0.5, while 12.4% of the subjects have a value > 0.5, showing abdominal obesity among 55 children at an early age. Our results point out the need for specific preventive and treatment interventions by identifying and implementing effective strate - gies, policies, and nutritional education programs in order to decrease the prevalence rate of obesity as well as the risk of metabolic disorders.