Self-assembled monolayers of reduced graphene oxide for robust 3D-printed supercapacitors.

Herein, additive manufacturing, which is extremely promising in different sectors, has been adopted in the electrical energy storage field to fabricate efficient materials for supercapacitor applications. In particular, Al2O3-, steel-, and Cu-based microparticles have been used for the realization of 3D self-assembling materials covered with reduced graphene oxide to be processed through additive manufacturing. Functionalization of the particles with amino groups and a subsequent "self-assembly" step with graphene oxide, which was contextually partially reduced to rGO, was carried out. To further improve the electrical conductivity and AM processability, the composites were coated with a polyaniline-dodecylbenzene sulfonic acid complex and further blended with PLA. Afterward, they were extruded in the form of filaments, printed through the fused deposition modeling technique, and assembled into symmetrical solid-state devices. Electrochemical tests showed a maximum mass capacitance of 163 F/g, a maximum energy density of 15 Wh/Kg at 10 A/g, as well as good durability (85% capacitance retention within 5000 cycles) proving the effectiveness of the preparation and the efficiency of the as-manufactured composites.

Multifunctional leather finishing vs. applications, through the addition of well-dispersed flower-like nanoparticles.

In the present paper, multifunctional flower-like nanoparticles were synthesized to be used in the leather finishing. They are capable of conferring simultaneously and synergistic antimicrobial, self-cleaning, light resistance, hydrophobic, mechanical, thermal, and fluorescent properties due to the presence of Ag, TiO2, and SiO2 NPs. These nanoparticles form a "flower-like" structure in which the "pistil" is made up of TiO2 and the "petals" that surround it of silver nanoparticles and silica nanoparticles, whose dimensions are of the order of ten nanometers. Their surfaces enjoy abundant hydrophilic functionalities to be dispersed within inks commonly used during the leather finishing process. Leathers functionalized with these nanomaterials showed significantly improved self-cleaning properties after 15 h of exposure to UV light, and antibacterial properties 10 times higher than that shown by the untreated samples. Aging tests were performed (ISO 105-B02, ISO 17228, SAEJ 2412). ΔE, color variation decreased by approximately 30%, if compared with samples not refined with flower-like NPs. Furthermore, the results of the mechanical tests (ISO 17076, FCA 50444) evidence amazing properties, e.g. abrasion resistance more than significantly improved, increase in resistance from 1500 cycles for the untreated samples to 3000 cycles for the leathers finished with flower-like NPs. The contact angle analysis, capturing the angle that traces the air-water to water-substrate interface from the origin of the air-water-substrate contact point at the edge, is practically unchanged after 10 s in the case of nanoparticles containing finishing.

Rough and Porous Micropebbles of CeCu2Si2 for Energy Storage Applications.

Supercapacitors have attracted considerable attention due to their advantages, including being lightweight and having rapid charge-discharge, a good rate capability, and high cyclic stability. Electrodes are one of the most important factors influencing the performance of supercapacitors. Herein, a three-dimensional network of rough and porous micropebbles of CeCu2Si2 has been prepared using a one-step procedure and tested for the first time as a supercapacitor electrode. The synthesized material was extensively characterized in a three-electrode configuration using different electrochemical techniques, such as cyclic voltammetry (CV), galvanostatic charge and discharge (GCD) tests, and electrochemical impedance spectroscopy (EIS). CeCu2Si2 shows rather high mass-capacitance values: 278 F/g at 1 A/g and 295 F/g at 10 mV/s. Moreover, the material exhibits remarkable long-term stability: 98% of the initial capacitance was retained after 20,000 cycles at 10 A/g and the Coulombic efficiency remains equal to 100% at the end of the cycles.

Iron Selenide Particles for High-Performance Supercapacitors.

Nowadays, iron (II) selenide (FeSe), which has been widely studied for years to unveil the high-temperature superconductivity in iron-based superconductors, is drawing increasing attention in the electrical energy storage (EES) field as a supercapacitor electrode because of its many advantages. In this study, very small FeSe particles were synthesized via a simple, low-cost, easily scalable, and reproducible solvothermal method. The FeSe particles were characterized using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD) measurements, and electrochemical impedance spectroscopy (EIS), revealing enhanced electrochemical properties: a high capacitance of 280 F/g at 0.5 A/g, a rather high energy density of 39 Wh/kg and a corresponding power density of 306 W/kg at 0.5 A/g, an extremely high cycling stability (capacitance retention of 92% after 30,000 cycles at 1 A/g), and a rather low equivalent series resistance (RESR) of ~2 Ω.

Synthesis and Electrical Percolation of Highly Amorphous Polyvinyl Alcohol/Reduced Graphene Oxide Nanocomposite.

Polyvinyl alcohol is the most commercially water-soluble biodegradable polymer, and it is in use for a wide range of applications. It shows good compatibility with most inorganic/organic fillers, and enhanced composites may be prepared without the need to introduce coupling agents and interfacial modifiers. The patented high amorphous polyvinyl alcohol (HAVOH), commercialized with the trade name G-Polymer, can be easily dispersed in water and melt processed. HAVOH is particularly suitable for extrusion and can be used as a matrix to disperse nanocomposites with different properties. In this work, the optimization of the synthesis and characterization of HAVOH/reduced graphene oxide (rGO) nanocomposite obtained by the solution blending process of HAVOH and Graphene Oxide (GO) water solutions and 'in situ' reduction of GO is studied. The produced nanocomposite presents a low percolation threshold (~1.7 wt%) and high electrical conductivity (up to 11 S/m) due to the uniform dispersion in the polymer matrix as a result of the solution blending process and the good reduction level of GO. In consideration of HAVOH processability, the conductivity obtained by using rGO as filler, and the low percolation threshold, the nanocomposite presented here is a good candidate for the 3D printing of a conductive structure.

Self-Suspended Nanoparticles for N-Alkylation Reactions: A New Concept for Catalysis.

The catalytic activity of snowman-like and core-shell Fe3O4/Au nanoparticles (NPs), obtained through a "wet chemistry" approach which directly restitutes nanocatalysts stable and highly active in the reaction medium, was tested towards N-alkylation reactions. The nanocatalysts were tested for the synthesis of secondary amines. The core-shell NPs, thanks to the surface properties, homogeneous dispersion and intimate connection with reagents in the catalyst medium, exhibited an excellent catalytic activity (e. g. >99 % yield and conversion of aniline in very short time and mild conditions). Owing to the magnetic part, the nanoparticles can be easily separated and reused, showing an almost stable activity after 10 cycles.

Application of Spray Drying Particle Engineering to a High-Functionality/Low-Solubility Milk Thistle Extract: Powders Production and Characterization.

Many natural compounds having antioxidant and anti-inflammatory activity are a potential target for new therapies against chronic inflammatory syndromes. The oral administration of functional herbal supplements may become a prevention strategy or therapy adjuvant for susceptible patients. A case study is our milk thistle (Silybum marianum) extract rich in silymarin complex. A water-soluble microencapsulated powder system was developed by a spray drying technique to improve the poor silymarin bioactivity after oral administration. Sodium carboxymethylcellulose (NaCMC) was employed as coating/swelling polymer matrix and sodium lauryl sulfate (SLS) as the surfactant (1:1:0.05 w/w/w). A H2O/EtOH/acetone (50/15/35 v/v/v) solvent system was used as liquid feed. The microsystems were capable of improving the in vitro dissolution and permeation rates, suggesting an enhancement of bioactivity after oral administration. The microsystems protect the antioxidant activity of silymarin after harsh storage conditions period and do not affect the anti-inflammatory properties of the raw extract (efficient already at lower concentrations of 0.312 mg/mL) to reduce dendritic cells (DCs) inflammatory cytokine secretion after lipopolysaccharide administration. This approach allows managing particle size, surface properties and release of bioactive agents improving the bioactivity of a herbal supplement and is also possibly applicable to many other similar natural products.

Conductive Adhesive Based on Mussel-Inspired Graphene Decoration with Silver Nanoparticles.

Decoration with silver nanoparticles was obtained by coating graphene with a polydopamine layer, able to induce spontaneous metallic nanoparticles formation without any specific chemical interfacial modifier, neither using complex instrumentation. The choice of dopamine was inspired by the composition of adhesive proteins in mussels, related to their robust attach to solid surfaces. The synthesis procedure started from graphite and involved eco-friendly compounds, such as Vitamin C and glucose as reducing agent and water as reaction medium. Silver decorated graphene was inserted as secondary nanofiller in the formulation of a reference conductive adhesive based on epoxy resin and silver flakes. A wide characterization of the intermediate materials obtained along the step procedure for the adhesive preparation was carried out by several techniques. We have found that the presence of nanofiller yields, in addition to an improvement of the thermal conductivity (up to 7.6 W/m · K), a dramatic enhancement of the electrical conductivity of the adhesive. In particular, starting from 3 · 102 S/cm of the reference adhesive, we obtained a value of 4 · 104 S/cm at a nanofiller concentration of 11.5 wt%. The combined double filler conductivity was evaluated by Zallen's model. The effect of the temperature on the resistivity of the adhesive has been also studied.

The state of research in Europe and in Italy: the risks of short-sighted decisions.

Research is facing declining funding rates everywhere, affecting the cultural and economic growth of some of major world powers. We looked at the choices on funding allocation made by the USA and by Europe, to compare priorities and analyze consequences. Also, within Europe, we focused on Italy and on its consistent brain-drain phenomenon, as an example of short-sighted research policies that appear to require not only the urgent infusion of monetary resources and the creation of new job opportunities, but also and especially a general change of cultural approach.

Oil lubricant tribological behaviour improvement through dispersion of few layer graphene oxide.

Few layer graphene oxide (GO) nanosheets were prepared by a very fast modified Hummers method and widely characterized. Avoiding further chemical reactions, trying to take advantage of the easy exfoliation of GO favoring the formation of a tribofilm, and using a methodology well known to the lubricant industry, they were added to a mineral oil by the help of a dispersant. The tribological behaviour of GO in mineral oil was investigated under a wide spectrum of conditions, from boundary and mixed lubrication to elastohydrodynamic regimes. A ball on disc setup tribometer has been used to verify the friction reduction due to nanosheets dispersed in mineral oil. Their good friction and anti-wear properties may possibly be attributed to the small and extremely thin laminated structure, which offer lower shear stress and prevent interaction between metal interfaces. Furthermore, the results clearly prove that graphene platelets in oil easily form a protective film to prevent the direct contact between steel surfaces and, thereby, improving the frictional behaviour of the base oil. This evidence is also related to the frictional coefficient trend in boundary regime.

An abridged photographic history of organ transplantation.

OBJECTIVES: Organ transplantation is one of the most remarkable therapeutic advances in modern medicine; it started as an experiment and has become a life-saving practice. We briefly describe the major milestones of this multidisciplinary clinical science, the challenges that it still faces, and we consider the crucial contribution that its example could set for other medical fields. MATERIALS AND METHODS: A review of the literature was conducted and a selection of images was made to complete a brief history of organ transplantation, with a particular focus on liver transplantation. RESULTS: The largest problem affecting organ transplantation today is the shortage of organs. Attention should be given to preserving the peculiar high ethical value that characterizes the very nature of organ transplantation. CONCLUSIONS: Methods successfully adopted by organ transplantation during the past 60 years can inspire promising fields, such as stem cell research, and provide useful tools to face the ethical challenges posed by scientific discoveries.

[Benign retroperitoneal schwannoma: a case report and review of the literature]. / Schwannoma benigno del retroperitoneo: caso clinico e revisione della letteratura.

Retroperitoneal schwannoma is a very rare benign tumour that accounts for only a small percentage of retroperitoneal tumours. The preoperative diagnosis is difficult and the only treatment is complete surgical excision. The authors report their experience with a case of a voluminous retroperitoneal mass in a 42-year- old male patient, incidentally discovered during a diagnostic search for a blunt abdominal trauma. Because of the unclear origin of this mass, the patient underwent periodic radiological and ultrasonographic examinations. Three years later, owing to a slight increase in this mass and vague abdominal discomfort reported by the patient, surgical excision was performed. Histological examination of the surgical specimen revealed an "ancient schwannoma". The patient is alive and well and has had no recurrence in the twenty months since surgery. The authors, after a short discussion of the subject, go on to examine the diagnostic and therapeutic treatments of this rare benign neoplasm, which always arouses lively clinical and scientific interest.

[Desmoid tumor of the chest wall foiling surgery]. / Desmoide della parete toracica, ad insorgenza postchirurgica.

AIM OF THE STUDY: The Authors report on a patient personally observed owing to a tumefaction, mimicking a pomelo, located on the posterior chest wall, in the same site of another past surgical operation dating back to four years ago. This tumefaction was clear at the inspection, not aching and hard-elastic at the palpation, mobile synchronously with respiratory movements, but unable to alter respiratory mechanics. CASE REPORT: The patient was subjected to laboratory tests, which showed nothing pathological, and to instrumental tests (RX and TAC of the chest, bony scintigraphy) which showed a roundish solid tumefaction, with no "secondary" interest of bony tissue. In this case, it was executed a posterior-lateral thoracothomy, at the VI intercostal space, in the area circumscribing the past surgical scar. The careful removal of the adhesions between the mass and the costal plane, not without the sacrifice of the periosteum, permitted us the total exeresis. The anatomo-pathological test showed a desmoid fibromatosis (desmoid tumor) extra-abdominal (12.5 x 9 x 5 cm). About this kind of neoplastic masses, the risk of post-surgical relapse is very high; so many Authors consider opportune a radio-chemical adjuvant therapy. In this case, the radical excision allowed the Authors to avoid the post surgery pharmacological treatment and to get no relapses after two years from the operation.

[Inguinal endometriosis]. / Le endometriosi del canale inguinale.

This study was conducted from September 2000 to September 2004 on 8 cases of inguinal canal endometriosis. All the patients presented an inguinocrural tumefaction of variable size. In 3 cases (symptomatic endometriosis), the patient's medical history yielded a preoperative diagnosis. In the other 5 cases (asymptomatic endometriosis) we obtained an incidental intraoperative diagnosis. In 2 of these, concomitant frank inguinocrural disease further hampered the preoperative diagnosis, while in the other 3 cases we were oriented towards an inguinal adeno-lymphatic disease. We found no signs of neoplastic transformation in our case series. The histological examination confirmed the diagnosis of endometriosis in all 8 cases, without any atypical cellular signs. From an analysis of the literature we deduced that the worldwide incidence of endometriosis is about 10% of the female population, though it is known that in the vast majority of cases there are few or no symptoms. Even today, despite the routine use of advanced diagnostic and surgical procedures, endometriosis foci are very often identified only incidentally owing to the greater incidence of asymptomatic or paucisymptomatic forms. The aim of our study is to stress the difficulty in diagnosing asymptomatic endometriosis and, above all, to suggest that, in the presence of a concomitant hernial pathology in a woman of child-bearing age, the diagnostic hypothesis of endometriosis should never be disregarded.

[Giant atypical muscle-involving lipoma of the right thigh: a case report and review of the literature]. / Lipoma atipico gigante intramuscolare della coscia destra: caso clinico e analisi della letteratura.

The clinical case reported here concerns a giant lipoma (22 x 12 x 10 cm; 2740 g) located in the distal region of the right thigh, in a subfascial zone. The patient was referred to our department for a relapse of thrombophlebitis of the right lower limb (occurring about two years earlier) and presented a large tumefaction of the mid third of thigh at objective examination, the presumed onset of which dated back about ten years after a traumatic accident. Ultrasonography confirmed the presence of the tumefaction but did not allow us to identify its origin with certainty. Musculoskeletal magnetic resonance imaging, however, revealed a gross expansive lesion closely connected to the distal part of the femur, suggesting its probable benign nature. The mass was totally resected without either muscle section or the sacrifice of periosteum. The histological findings indicated an atypical lipomatous tumour. The therapy of giant lipomas is invariably surgical excision. Nevertheless, the high risk of relapse (which is typical of this kind of neoplastic proliferation) despite radical resection, makes a systematic postoperative follow-up necessary.

Giant bilateral ovarian cysts in an adolescent masked by obesity and mimicking ascites: a case report.

Ovarian cysts are a common pathology after the 4th decade of life. We can find either smaller functional, non-neoplastic ones (belonging to the follicular and luteinic varieties) or larger tumoral cysts, which, however, are usually benign. These may be of the serous or mucinous type and can sometimes reach really large sizes. Reports of giant ovarian manifestations were more frequent a few decades ago. Prior to the advent of modern radiological, ultrasonographic, tomographic and magnetic resonance imaging techniques, diagnosis was often difficult. Nevertheless, even today, in some cases (as a result of pronounced obesity, for example, associated perhaps with diagnostic negligence), cases of giant ovarian cysts may still be encountered. We report the case of a (previously obese) 19-year-old female, admitted to our hospital for presumed ascites, identified and ultrasonographically misdiagnosed by her gynaecologist. The patient was, in fact, suffering from giant serous cystoadenomas in both ovaries.