Nanotechnology measurements of the Young's modulus of polymeric materials

Making use of atomic force microscopy (AFM) —known as the state-of-the-art technology for handling matter on an atomic and molecular scale—, this paper describes the use of a nanotechnology technique for characterizing properties of polymeric materials. AFM measurement on two materials (polyamide and polystyrene) allowed to compare the performance of two distinct multi-asperity adhesion models based on the JKR (Johnson-Kendall-Robert) and DMT (Derajaguin- Muller-Toporov) theories, when assessing the Young’s Modulus (modulus of elasticity) of the investigated materials. Experimental results confirm that the JKR model processed through a MatLab algorithm produces more reliable results of the Young’s Modulus than the DMT model built-in in the AFM software

Sulfated and carboxylated nanocellulose for Co+2 adsorption

Regarding metals adsorption from aqueous solutions, nanocellulose emerges as a potential material, due to the many functionalization possibilities and enhanced surface contact area (nanostructured nature). In the present work, sulfated and carboxylated nanocellulose samples were obtained through sulfuric acid hydrolysis (S-CNC) and oxidation by TEMPO (CNF). The obtained nanofibers were characterized through multiple techniques, which XRD data indicated the presence of a-cellulose crystals, with crystallinity indexes equal to 72.3% (S-CNC) and 69.3% (CNF). Expressive morphological differences were revealed, whiskers particles for S-CNC, and elongated nanofibrils for CNF, with average thickness of 9.99 and 5.61 nm, respectively. The desired functionalization with carboxylate groups was evidenced based on FTIR data (CNF). A significant and homogeneous presence of sulfur was evidenced through SEM/EDS (S-CNC). The synthesized nanofibers were next applied to cobalt (Coþ2 ) adsorption from aqueous solutions at room temperature. On both cases, expressive maximum cobalt recoveries have been achieved, 90% (CNF) and 87% (S-CNC), for contact times higher than 30 and 45 min, respectively. The adsorptive capacities evaluated through ICP-OES from liquid phase data (87 mg g 1 S-CNC; 90 mg g 1 CNF) were both significantly higher than the values determined through LA-ICP-MS (10.5 mg Co g 1 S- CNC; 31.5 mg Co g 1 CNF)

Ion irradiation of N2O ices and NO2:N2O4 ice mixtures: first steps to understand the evolution of molecules with the N−O bond in space

Astronomical observations towards star forming regions have revealed the presence of molecules with the N-O bond such as NO, N2O, and HNO. These species are considered potential precursors of prebiotic molecules. Thus understanding nitrogen and oxygen chemistry may help us to better understand the origin and evolution of prebiotic molecules in space. However, species with the N−O bond are poorly studied and laboratory works on the effects induced on them by solar wind and galactic cosmic rays are still scarce. For this, we wanted to study the effects of ion bombardment on molecules with the N−O bond. We focus here on N2O ices and NO2:N2O4 = 1:1 ice mixtures (at 16 and 50/60 K) irradiated with 200 keV protons. Infrared transmission spectroscopy (8000−500 cm-¹; 1.25−20 μm) was used to analyze the samples. Irradiation of N2O ices and NO2:N2O4 ice mixtures produces comparable effects independent of the irradiation temperature, NO being the main product. Moreover, we show that the maximum amount of N2O and N2O4 destroyed by irradiation, at the highest dose reached in our experiments, is equal to about 98 and 70%, respectively. The dose range covered in the experiments has been compared with the astrophysical timescale of surface processing in space, showing that irradiation of N2O and NO2:N2O4 mixtures can produce, within 10⁵−10⁸ years, amounts of solid NO ice detectable towards star forming regions by the James Webb Space Telescope

Impact of use of oral anticancer drugs on activity of Italian oncology practices: results of a survey conducted by the Italian Society of Medical Oncology (AIOM)

AIMS AND BACKGROUND: In recent years, the number of oral anticancer drugs used in clinical practice has rapidly increased. The Italian Society of Medical Oncology (AIOM) conducted a survey to describe the impact of the use of oral anticancer drugs on the daily activity of Italian oncology practices. METHODS AND STUDY DESIGN: A survey questionnaire was distributed to the coordinators of the regional sections of AIOM. A 6-month period was considered, from January 1, 2010 to June 30, 2010. The survey addressed (1) quantitative aspects of the use of oral anticancer drugs; (2) practical aspects in the management of patients treated with these drugs; (3) issues related to treatment costs and reimbursement procedures. RESULTS: Thirty-six questionnaires were received from institutions distributed throughout the Italian territory. Oral anticancer drugs (both chemotherapy and molecularly targeted agents) accounted for a significant proportion (17%) of prescribed treatments. Among the responding institutions, there were different dispensation procedures of oral drugs to patients: drugs were dispensed by the pharmacist (57%) or directly by the medical oncologist (23%) or nurse (20%). The medical oncologist played a major role in the communication with patients (73% alone and a further 24% in cooperation with other professional figures) and was the point of reference in the event of side effects in 97% of cases. In most cases, the reimbursement of drug costs was separated ("File F" procedure) from the flat fare received by the hospital for outpatient visits or day-hospital access. CONCLUSIONS: Optimal organization of oral anticancer treatment warrants the cooperation and integration of multiple professional figures. At least three figures are involved in patient management in the hospital: the medical oncologist, the nurse, and the hospital pharmacist. Oral anticancer treatments are associated with specific reimbursement issues: in the majority of cases, the cost of the drug is reimbursed separately from the cost of patient access

Breast cancer "tailored follow-up" in Italian oncology units: a web-based survey

urpose: Breast cancer follow-up procedures after primary treatment are still a controversial issue. Aim of this study was to investigate, through a web-based survey, surveillance methodologies selected by Italian oncologists in everyday clinical practice. Methods: Referents of Italian medical oncology units were invited to participate to the study via e-mail through the SurveyMonkey website. Participants were asked how, in their institution, exams of disease staging and follow-up are planned in asymptomatic women and if surveillance continues beyond the 5th year. Results: Between February and May 2013, 125 out of 233 (53.6%) invited referents of Italian medical oncology units agreed to participate in the survey. Ninety-seven (77.6%) referents state that modalities of breast cancer follow-up are planned according to the risk of disease progression at diagnosis and only 12 (9.6%) oncology units apply the minimal follow-up procedures according to international guidelines. Minimal follow-up is never applied in high risk asymptomatic women. Ninety-eight (78.4%) oncology units continue follow-up in all patients beyond 5 years. Conclusions: Our survey shows that 90.4% of participating Italian oncology units declare they do not apply the minimal breast cancer follow-up procedures after primary treatment in asymptomatic women, as suggested by national and international guidelines. Interestingly, about 80.0% of interviewed referents performs the so called "tailored follow-up", high intensity for high risk, low intensity for low risk patients. There is an urgent need of randomized clinical trials able to determine the effectiveness of risk-based follow-up modalities, their ideal frequency and persistence in time

Supramolecular hybrid organic-inorganic multicomponent architectures in solution and on surface

Supramolecular architectures can be built-up from a single molecular component (building block) to obtain a complex of organic or inorganic interactions creating a new emergent condensed phase of matter, such as gels, liquid crystals and solid crystal. Further the generation of multicomponent supramolecular hybrid architecture, a mix of organic and inorganic components, increases the complexity of the condensed aggregate with functional properties useful for important areas of research, like material science, medicine and nanotechnology. One may design a molecule storing a recognition pattern and programming a informed self-organization process enables to grow-up into a hierarchical architecture. From a molecular level to a supramolecular level, in a bottom-up fashion, it is possible to create a new emergent structure-function, where the system, as a whole, is open to its own environment to exchange energy, matter and information. “The emergent property of the whole assembly is superior to the sum of a singles parts”. In this thesis I present new architectures and functional materials built through the selfassembly of guanosine, in the absence or in the presence of a cation, in solution and on the surface. By appropriate manipulation of intermolecular non-covalent interactions the spatial (structural) and temporal (dynamic) features of these supramolecular architectures are controlled. Guanosine G7 (5',3'-di-decanoil-deoxi-guanosine) is able to interconvert reversibly between a supramolecular polymer and a discrete octameric species by dynamic cation binding and release. Guanosine G16 (2',3'-O-Isopropylidene-5'-O-decylguanosine) shows selectivity binding from a mix of different cation's nature. Remarkably, reversibility, selectivity, adaptability and serendipity are mutual features to appreciate the creativity of a molecular self-organization complex system into a multilevelscale hierarchical growth. The creativity - in general sense, the creation of a new thing, a new thinking, a new functionality or a new structure - emerges from a contamination process of different disciplines such as biology, chemistry, physics, architecture, design, philosophy and science of complexity

The Supramolecular Chemistry between Eastern Philosophy and The Complexity Theory

Over the past few years, supramolecular self-assembly chemistry has emerged as a new exciting field in which theoretical and experimental studies of structure and function of supramolecules have become a focus, and the importance of DNA, RNA, and peptides as important components to the fundamental development in life science has become a new interdisciplinary frontier in life science and other science. How to explain the origin of life phenomena has also become a hotspot. Here author expresses his some opinions to understand the self-assembly phenomena of nature from western philosophy view, explores the application prospects, and discusses the concepts, issues, approaches, and challenges, with the aim of stimulating a broader interest in developing supramolecular chemistry

Heterogeneous flow chemistry through bamboo-based microfluidic reactors

The rapid development of flow chemistry and its related microfluid technology has accelerated the innovation in material science and the research into alternative, environmentally, and cost-effective microfabrication procedures. This article reviews the latest advances in bamboo-based microfluidic devices, highlighting the heterogeneous catalysis in flow mode through the three-dimensional (3D) structures of the plant’s vascular bundles. Different strategies for immobilizing catalysts (metal and enzymes) and the design of the lignocellulosic-based flow reactor are presented