Water-Assisted Hole Trapping at the Highly Curved Surface of Nano-TiO2 Photocatalyst.

Heterogeneous photocatalysis is vital in solving energy and environmental issues that this society is confronted with. Although photocatalysts are often operated in the presence of water, it has not been yet clarified how the interaction with water itself affects charge dynamics in photocatalysts. Using water-coverage-controlled steady and transient infrared absorption spectroscopy and large-model (∼800 atoms) ab initio calculations, we clarify that water enhances hole trapping at the surface of TiO2 nanospheres but not of well-faceted nanoparticles. This water-assisted effect unique to the nanospheres originates from water adsorption as a ligand at a low-coordinated Ti-OH site or through robust hydrogen bonding directly to the terminal OH at the highly curved nanosphere surface. Thus, the interaction with water at the surface of nanospheres can promote photocatalytic reactions of both oxidation and reduction by elongating photogenerated carrier lifetimes. This morphology-dependent water-assisted effect provides a novel and rational basis for designing and engineering nanophotocatalyst morphology to improve photocatalytic performances.

Interfacing CRYSTAL/AMBER to Optimize QM/MM Lennard⁻Jones Parameters for Water and to Study Solvation of TiO2 Nanoparticles.

Metal oxide nanoparticles (NPs) are regarded as good candidates for many technological applications, where their functional environment is often an aqueous solution. The correct description of metal oxide electronic structure is still a challenge for local and semilocal density functionals, whereas hybrid functional methods provide an improved description, and local atomic function-based codes such as CRYSTAL17 outperform plane wave codes when it comes to hybrid functional calculations. However, the computational cost of hybrids are still prohibitive for systems of real sizes, in a real environment. Therefore, we here present and critically assess the accuracy of our electrostatic embedding quantum mechanical/molecular mechanical (QM/MM) coupling between CRYSTAL17 and AMBER16, and demonstrate some of its capabilities via the case study of TiO2 NPs in water. First, we produced new Lennard⁻Jones (LJ) parameters that improve the accuracy of water⁻water interactions in the B3LYP/TIP3P coupling. We found that optimizing LJ parameters based on water tri- to deca-mer clusters provides a less overstructured QM/MM liquid water description than when fitting LJ parameters only based on the water dimer. Then, we applied our QM/MM coupling methodology to describe the interaction of a 1 nm wide multilayer of water surrounding a spherical TiO2 nanoparticle (NP). Optimizing the QM/MM water⁻water parameters was found to have little to no effect on the local NP properties, which provide insights into the range of influence that can be attributed to the LJ term in the QM/MM coupling. The effect of adding additional water in an MM fashion on the geometry optimized nanoparticle structure is small, but more evident effects are seen in its electronic properties. We also show that there is good transferability of existing QM/MM LJ parameters for organic molecules⁻water interactions to our QM/MM implementation, even though these parameters were obtained with a different QM code and QM/MM implementation, but with the same functional.

Modelling realistic TiO2 nanospheres: A benchmark study of SCC-DFTB against hybrid DFT.

TiO2 nanoparticles (NPs) are nowadays considered fundamental building blocks for many technological applications. Morphology is found to play a key role with spherical NPs presenting higher binding properties and chemical activity. From the experimental point of view, the characterization of these nano-objects is extremely complex, opening a large room for computational investigations. In this work, TiO2 spherical NPs of different sizes (from 300 to 4000 atoms) have been studied with a two-scale computational approach. Global optimization to obtain stable and equilibrated nanospheres was performed with a self-consistent charge density functional tight-binding (SCC-DFTB) simulated annealing process, causing a considerable atomic rearrangement within the nanospheres. Those SCC-DFTB relaxed structures have been then optimized at the DFT(B3LYP) level of theory. We present a systematic and comparative SCC-DFTB vs DFT(B3LYP) study of the structural properties, with particular emphasis on the surface-to-bulk sites ratio, coordination distribution of surface sites, and surface energy. From the electronic point of view, we compare HOMO-LUMO and Kohn-Sham gaps, total and projected density of states. Overall, the comparisons between DFTB and hybrid density functional theory show that DFTB provides a rather accurate geometrical and electronic description of these nanospheres of realistic size (up to a diameter of 4.4 nm) at an extremely reduced computational cost. This opens for new challenges in simulations of very large systems and more extended molecular dynamics.

Catalysis under Cover: Enhanced Reactivity at the Interface between (Doped) Graphene and Anatase TiO2.

The "catalysis under cover" involves chemical processes which take place in the confined zone between a 2D material, such as graphene, h-BN, or MoS2, and the surface of an underlying support, such as a metal or a semiconducting oxide. The hybrid interface between graphene and anatase TiO2 is extremely important for photocatalytic and catalytic applications because of the excellent and complementary properties of the two materials. We investigate and discuss the reactivity of O2 and H2O on top and at the interface of this hybrid system by means of a wide set of dispersion-corrected hybrid density functional calculations. Both pure and boron- or nitrogen-doped graphene are interfaced with the most stable (101) anatase surface of TiO2 in order to improve the chemical activity of the C-layer. Especially in the case of boron, an enhanced reactivity toward O2 dissociation is observed as a result of both the contribution of the dopant and of the confinement effect in the bidimensional area between the two surfaces. Extremely stable dissociation products are observed where the boron atom bridges the two systems by forming very stable B-O covalent bonds. Interestingly, the B defect in graphene could also act as the transfer channel of oxygen atoms from the top side across the C atomic layer into the G/TiO2 interface. On the contrary, the same conditions are not found to favor water dissociation, proving that the "catalysis under cover" is not a general effect, but rather highly depends on the interfacing material properties, on the presence of defects and impurities and on the specific reaction involved.

Pulsed electromagnetic fields (PEMF) as a valid tool in orthognathic surgery to reduce post-operative pain and swelling: a prospective study.

PURPOSE: PEMF (pulsed electromagnetic fields) founds application in several medical fields to accelerate bone wounds healing and to reduce inflammation. The aim of our study was to evaluate the effectiveness of PEMF in reducing postoperative swelling and pain in patients undergoing orthognathic surgery. METHODS: A prospective observational monocentric study was conducted on a sample of 30 patients undergone to orthognathic surgery in Maxillofacial Surgery Unit of University of Naples Federico II. The patients who followed these inclusion criteria were enrolled in the study: age ≥ 18 years, Class III malocclusion, Surgical procedure of Le Fort I osteotomy + Bilateral Sagittal Split Osteotomy (BSSO), Written informed consent. Patients were divided into two groups: Group SD) postoperative standard treatment with medical therapy and cryotherapy, Group SD + PEMF) postoperative standard therapy + PEMF. Each patient underwent a 3D facial scan, at one (1d) and four (4d) days after surgery to compare the swelling reduction. The pain score was assessed through VAS score and analgesics administration amount. RESULTS: In SD + PEMF group, the facial volume reduction between 1d and 4d scan was on average 56.2 ml (6.23%), while in SD group, it was 23.6 ml (2.63%). The difference between the two groups was 3.6% (p = 0.0168). VAS pain values were significantly higher in SD group compared to SD + PEMF group in the second day after surgery (P = 0.021) and in the total 4 days (P = 0.008). CONCLUSIONS: Our data suggest that PEMF is valid tool to promote faster postoperative swelling and pain reduction in patients undergoing orthognathic surgery.

Extracranial Nasosinusal Meningioma: A Case Report of a Rare Entity.

Meningiomas are the most common neoformations of the central nervous system, and represent the 33% of all intracranial neoplasms. The nasosinusal tract is involved in 24% of cases of extracranial localization. The aim of our paper is to present the case of a patient with an ethmoidal sinus meningioma.

Three Different Types of Fat Grafting for Facial Systemic Sclerosis: A Case Series.

Systemic sclerosis (SSc) is a heterogeneous, chronic connective tissue disease, characterized by skin fibrosis as well as vascular and visceral lesions. It can involve the lungs, heart, kidneys, gastrointestinal tract, and bones. The orofacial manifestations of SSc can cause functional, aesthetic, and social distress, resulting in significant psychological implications for the patients. In recent decades, fat grafting improved the aesthetic outcomes in terms of volume deficiency, contour asymmetry, and skin elasticity of the face thanks to the regenerative action of the stem cells contained within it. We describe five cases of a patient with SSc treated with fat grafting used to correct volume loss and facial elasticity of the lips and perioral region on the middle and lower third of the face. All the patients received regular postoperative checks at weeks 1 and 2. A multiple choice questionnaire was administered to assess the degree of tolerability of the procedure. The reliability of the questionnaire was evaluated by calculating the Cronbach alpha using the MedCalc Statistical Software version 20.113. The aim of our study is to describe three different types of fat grafting used to correct volume loss and restore facial elasticity of the lips and perioral region on the middle and lower third of the face.

Electrochemotherapy as a First Line Treatment in Recurrent Squamous Cell Carcinoma of the Oral Cavity and Oropharynx PDL-1 Negative and/or with Evident Contraindication to Immunotherapy: A Randomized Multicenter Controlled Trial.

BACKGROUND: A significant proportion of patients with head and neck squamous cell carcinoma (HNSCC) have advanced-stage disease (stages III to IVB) that do not respond to therapy despite aggressive, site-specific multimodality therapy. A great number of them will develop disease recurrence, with up to 60% risk of local failure and up to 30% risk of distant failure. Therapy can be very demanding for the patient especially when important anatomical structures are involved. For these reasons, therapies that preserve organ functionality in combination with effective local tumor control, like electrochemotherapy (ECT), are of great interest. Until few months ago, systemic cetuximab + platinum-based therapy + 5-fluorouracil represented the standard treatment for HNSCC relapses with a median overall survival of 10.1 months and an objective response rate of 36%. Recently the results of KEYNOTE-048 study were published and a new combination of monoclonal antibody named pembrolizumab and chemotherapy emerged as standard first line therapy of recurrent or metastatic tumor that overexpress tissue PDL-1 (Programmed Death 1 ligand). Nevertheless, a variable percentage from 10 to 15% of patients with recurrent/metastatic disease have a tumor that does not overexpress tissue PDL-1, and therefore, according to the results of the KEYNOTE-048 study, does not benefit from replacement of cetuximab with pembrolizumab. These patients will be treated with the "gold standard": cetuximab, cisplatin/carboplatin and 5-fluorouracil. AIM: To verify whether electrochemotherapy performed with bleomycin of HNSCC relapses of the oral cavity and oropharynx (single relapse on T) is able to lead to an increase in the objective response rate in comparison with the systemic treatment with cetuximab + platinum-based therapy + 5-fluorouracil in patients with PDL-1 negative tumors. METHODS: The phase IIb study involves the enrolment of 96 patients who meet the inclusion criteria (48 in the control arm and 48 in the treatment arm). The control arm involves the treatment of HNSCC with systemic treatment (cetuximab + platinum-based therapy + 5-fluorouracil). The treatment arm involves the ECT with bleomycin. The primary objective is to verify the objective response rate of patients in the control arm compared to the treatment arm.

Pre-Treatment Neutrophil-to-Lymphocyte and Platelet-to-Lymphocyte Ratios as Predictors of Occult Cervical Metastasis in Clinically Negative Neck Supraglottic and Glottic Cancer.

Background. Among patients with diagnosis of Laryngeal Squamous Cell Carcinoma (LSCC), up to 37.5% of cases may have occult metastasis (OM), and this feature is linked to poor prognosis and high rate of local recurrence. The role of elective neck dissection (END) in clinically negative neck (cN0) LSCC remains controversial. It is of great value to search for low-cost and easily detectable indicators to predict the risk of OM in laryngeal cancer. Recent reports have shown that high values of the neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) represent a negative prognostic factor in head and neck cancers. The aim of our study has been to investigate the value of pre-treatment NLR and PLR with regard to predicting occult cervical metastasis in cN0 supraglottic and glottic LSCC. Materials and methods. Data of patients affected by LSCC, who had been surgically treated by means of laryngectomy (total, horizontal partial and supracricoid) and END between January 2006 and January 2021, were retrospectively reviewed, using information retrieved from a database dedicated to such procedures in a single tertiary care referral institute. Results. A total of 387 patients were treated for LSCC at our Institute from 2006 to 2021, but only 108 of them met the inclusion criteria. The median age at the time of diagnosis was 64 years (range, 39-89 years). All the tumors were treated with a laryngectomy and an END. A total of 27.7% of patients were found positive for neck node metastasis (the pN+ group), while 78/108 (72.3%) patients were found to be negative for the presence of neck metastasis (the pN0 group). High values of NLR, but not PLR, significantly correlated with the probability of OM, and according to the iterative algorithm of Newton-Raphson, an NLR value of 2.26 corresponds to a probability of OM of 20%. Conclusion. Our analysis revealed a statistical correlation between high NLR pre-treatment values and positive neck OM in patients with LSCC.

Effects of urban growth spatial pattern (UGSP) on the land surface temperature (LST): A study in the Po Valley (Italy).

Sealed surfaces greatly influence Urban Heat Island (UHI) effects. In this respect, both the composition and spatial patterns of anthropogenic land use play an important role in local thermal pattern. The urban environments' climate change adaptation strategy needs adequate knowledge systems urban planners can use to organise and design more resistant and resilient urban spaces. This study examined the relationship between Land Surface Temperature (LST) variations and increasing urbanised areas during the period 2001-2011 in the Po Valley, utilising different urban growth spatial patterns (UGSP). Remotely sensed LST data was obtained from MODIS (MODerate Resolution Imaging Spectroradiometer) at a resolution of 1 km/pixel for an 11 year-period, from 2001 to 2011, with urbanisation data from the ISTAT map (nominal scale 1:10,000) respectively for the 2001 and 2011 time sections. The relationship between dependent (mean annual daytime, nighttime and daily values) and independent (urbanised areas) variables were investigated through ANOVA test and post-hoc analysis (p < 0.01) for all defined UGSP. Results showed that there is a decreasing LST range (in all conditions) associated with progressive increase of urbanised areas. Furthermore, clustered patterns urban growth have a statistically significant relationship with daytime, nighttime and daily conditions while dispersed pattern urban growth have the same with nighttime only. The outcomes are helpful for understanding the effects of different UGSP, which have significant implications for urban planning, and identifying the critical territorial sectors in need of sustainable mitigation actions.

Curved TiO2 Nanoparticles in Water: Short (Chemical) and Long (Physical) Range Interfacial Effects.

In most technological applications, nanoparticles are immersed in a liquid environment. Understanding nanoparticles/liquid interfacial effects is extremely relevant. This work provides a clear and detailed picture of the type of chemistry and physics taking place at the prototypical TiO2 nanoparticles/water interface, which is crucial in photocatalysis and photoelectrochemistry. We present a multistep and multiscale investigation based on hybrid density functional theory (DFT), density functional tight-binding, and quantum mechanics/molecular mechanics calculations. We consider increasing water partial pressure conditions from ultra-high vacuum up to the bulk water environment. We first investigate single water molecule adsorption modes on various types of undercoordinated sites present on a realistic curved nanoparticle (2-3 nm) and then, by decorating all the adsorption sites, we study a full water monolayer to identify the degree of water dissociation, the Brønsted-Lowry basicity/acidity of the nanoparticle in water, the interface effect on crystallinity, surface energy, and electronic properties, such as the band gap and work function. Furthermore, we increase the water coverage by adding water multilayers up to a thickness of 1 nm and perform molecular dynamics simulations, which evidence layer structuring and molecular orientation around the curved nanoparticle. Finally, we clarify whether these effects arise as a consequence of the tension at the water drop surface around the nanosphere by simulating a bulk water up to a distance of 3 nm from the oxide surface. We prove that the nanoparticle/water interfacial effects go rather long range since the dipole orientation of water molecules is observed up to a distance of 5 Å, whereas water structuring extends at least up to a distance of 8 Å from the surface.

Water Multilayers on TiO2 (101) Anatase Surface: Assessment of a DFTB-Based Method.

A water/(101) anatase TiO2 interface has been investigated with the DFT-based self-consistent-charge density functional tight-binding theory (SCC-DFTB). By comparison of the computed structural, energetic, and dynamical properties with standard DFT-GGA and experimental data, we assess the accuracy of SCC-DFTB for this prototypical solid-liquid interface. We tested different available SCC-DFTB parameters for Ti-containing compounds and, accordingly, combined them to improve the reliability of the method. To better describe water energetics, we have also introduced a modified hydrogen-bond-damping function (HBD). With this correction, equilibrium structures and adsorption energies of water on (101) anatase both for low (0.25 ML) and full (1 ML) coverages are in excellent agreement with those obtained with a higher level of theory (DFT-GGA). Furthermore, Born-Oppenheimer molecular dynamics (MD) simulations for mono-, bi-, and trilayers of water on the surface, as computed with SCC-DFTB, evidence similar ordering and energetics as DFT-GGA Car-Parrinello MD results. Finally, we have evaluated the energy barrier for the dissociation of a water molecule on the anatase (101) surface. Overall, the combined set of parameters with the HBD correction (SCC-DFTB+HBD) is shown to provide a description of the water/water/titania interface, which is very close to that obtained by standard DFT-GGA, with a remarkably reduced computational cost. Hence, this study opens the way to the future investigations on much more extended and realistic TiO2/liquid water systems, which are extremely relevant for many modern technological applications.

Cartografias do corpo em tempos pandêmicos / Cartographies of the Body in Pandemic Times

Como Fox e Alldred (2020) consideram, o dualismo Cultura / Natureza forneceu aos filósofos, cientistas e cientistas sociais pós-iluministas uma maneira elegante de estabelecer limites para as respectivas preocupações das ciências sociais e naturais (ver também Barad, 2007; Braidotti, 2013; Fullagar et al., 2019). Este dualismo tem permitido a criação de distinções entre corpos e modos de estar no mundo "modernos" (leia-se "civilizados") e "tradicionais" (leia-se "primitivos"). No entanto, quando questões pertencentes à incorporação do social são exploradas criticamente, a influência sobre o bem-estar do entorno construído, as transições climáticas e a pandemia de Covid-19 em curso começam a problematizar tais formas, como é argumentado nas últimas três décadas por autores com perspectivas feministas, pós-humanas, novo-materialistas e político-ecológicas, entre outras. Dando continuidade a um diálogo permanente iniciado em 2018 entre acadêmicos e ativistas da América Latina e Europa, organizamos o seminário online "Religando o nexo natureza-cultura-corpo: práticas e epistemologias". O evento virtual desenvolvido em duas partes explorou como os territórios inter-relacionados de saúde, atividade física e educação podem ser repensados a partir de perspectivas que desestabilizam as fronteiras ontológicas estabelecidas entre natureza, cultura e corpo, e suas possíveis articulações. Este artigo é a transcrição da segunda sessão, denominada "Cartografias do corpo em tempos de pandemia", e apresenta os diálogos entre Alice del Gabbo, Carla Panico, Gianluca De Fazio, Alexandre Fernandez Vaz e Eduardo Galak, pesquisadores da Itália, Portugal, Brasil e Argentina.

Theoretical Studies of Oxygen Reactivity of Free-Standing and Supported Boron-Doped Graphene.

Graphene inertness towards chemical reactivity can be considered as an accepted postulate by the research community. This limit has been recently overcome by chemically and physically modifying graphene through non-metal doping or interfacing with acceptor/donor materials (metals or semiconductors). As a result, outstanding performances as catalytic, electrocatalytic, and photocatalytic material have been observed. In this critical Review we report computational work performed, by our group, on the reactivity of free-standing, metal- and semiconductor-supported B-doped graphene towards oxygen, which is at the basis of extremely important energy-related chemical processes, such as the oxygen reduction reaction. It appears that a combination of doping and interfacing approaches for the activation of graphene can open unconventional and unprecedented reaction paths, thus boosting the potential of modified graphene in many chemical applications.