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The development and growth of the territory has for centuries been conditioned by the availability of resources on site. The minor architecture which is presented as a vast and varied repertoire of unique architectural forms, perfected over time to meet the needs of living places, is the repository of the formal and cultural testimonies that represent the integration between man and environment, which took place in a constant process of adaptation and enhancement of limits and resources in terms of climate, materials, soil morphology and geology. The "not only formal" result of this growth process is a consolidated iconography that summarizes the profound reasons for building through techniques developed according to the characteristics of the available materials and the needs of life and daily work, an absolute synthesis between form and function that gives rise to the repertoire of the lexicon of the architecture of a place and of the landscape. Starting from these reflections, the proposed study seeks to investigate the reasons for the constructive lexicon of some examples of vernacular architecture related to different contexts, identifying the reasons for the constructive choices in terms of relationships between the function of technical elements and construction characteristics; the purpose of this approach is to regulate constructive interventions in consolidated settlements of vernacular architecture by proposing a study methodology that highlights the rules and reasons for those constructive choices so that purely formal distortions and misunderstandings do not occur in current practices. The selected case studies are the rural settlements of Terzigno, a municipality in the province of Naples (Italy) on the slopes of Vesuvius and some of the rural settlements in the Danube Delta, in Romania. [ABSTRACT FROM AUTHOR]

We report an experimental investigation on the sintering process induced in fumed silica powders by isochronal thermal treatments at T=1270 K. Three types of fumed silica are considered, consisting of amorphous SiO2 (a-SiO2) particles with mean diameters 7, 14, and 40 nm. The study is performed by atomic force microscopy (AFM), to follow the morphological changes, and by Raman scattering, to obtain information on the concomitant structural modifications. The former method indicates that the sintering process proceeds by aggregation of single particles into larger grains, whose sizes increase with the thermal treatment duration. Furthermore, for each fumed silica type considered, the quantitative analysis of the AFM images shows that the grain growth process takes place approximately at constant rate for thermal treatment durations up to 290 h. Nevertheless, the value of the grain growth rate is sensitive to the system properties. In fact, it is found to increase with decreasing the particle mean diameter, giving a strong quantitative evidence of the size-dependence of the sintering process. On the other hand, Raman measurements indicate that the structure of the as-received fumed silica nanoparticles is significantly modified with respect to that of ordinary bulk a-SiO2, in agreement with previous experimental evidences. However, it rapidly relaxes upon thermal treatment at T=1270 K and its characterizing features are almost completely lost after treatment for about 80 h. Finally, the comparison of AFM and Raman data shows that the nanoparticles structure are completely relaxed (resembling that of bulk a-SiO2) when the grains formed by thermal treatment reach diameters greater than about 43 nm, indicating that it represents the characteristic size above which the effects of spatial confinement on the structure of the material become almost negligible. [ABSTRACT FROM AUTHOR]

We report an experimental investigation by electron paramagnetic resonance of the doublet of lines split by ∼1.3 mT and centered on the E′γ center resonance line in the spectrum of irradiated amorphous SiO2. Commercial and sol-gel materials, some of which subjected to hydrogen-deuterium exchange, were investigated. Exposure to γ or β rays at room temperature of the samples and subsequent thermal treatments were carried out to induce the defects and to study their thermal stability. In all the materials used the ratio between the signal of the E′γ centers and that of the 1.3 mT doublet is constant and independent of the OH and OD contents. Furthermore, the 1.3 mT doublet and the E′γ center feature similar thermal stability. These results support the attribution of the 1.3 mT doublet to the hyperfine interaction between the unpaired electron magnetic moment of the E′γ center and the nuclear magnetic moment of a second near neighboring 29Si atom. Our results also suggest that the E′γ site needs an appropriate surrounding of 29Si in back-bond configuration to experience this hyperfine interaction. [ABSTRACT FROM AUTHOR]

We report an experimental investigation by electron paramagnetic resonance of the doublet of lines split by ∼1.3 mT and centered on the E′γ center resonance line in the spectrum of irradiated amorphous SiO2. Commercial and sol-gel materials, some of which subjected to hydrogen-deuterium exchange, were investigated. Exposure to γ or β rays at room temperature of the samples and subsequent thermal treatments were carried out to induce the defects and to study their thermal stability. In all the materials used the ratio between the signal of the E′γ centers and that of the 1.3 mT doublet is constant and independent of the OH and OD contents. Furthermore, the 1.3 mT doublet and the E′γ center feature similar thermal stability. These results support the attribution of the 1.3 mT doublet to the hyperfine interaction between the unpaired electron magnetic moment of the E′γ center and the nuclear magnetic moment of a second near neighboring 29Si atom. Our results also suggest that the E′γ site needs an appropriate surrounding of 29Si in back-bond configuration to experience this hyperfine interaction. [ABSTRACT FROM AUTHOR]

The sintering process induced in fumed silica powders by isochronal thermal treatments is examined. The comparison of atomic force microscopy (AFM) and Raman data has shown that the nanoparticles structure are relaxed when the grains formed by thermal treatment reach diameters greater than 43 nm, which has represented the size above which the effects of spatial confinement on the structure of the material has become almost negligible.

Electron paramagnetic resonance of the doublet of lines split by 1.3 mT and centered on the [E.sub.[gamma].sup.t] center resonance line in the spectrum of irradiated amorphous Si[O.sub.2] is examined. The results have shown that the [E.sub.[gamma].sup.t] site requires an appropriate surrounding of [super 29]Si in back-bond configuration to experience the hyperfine interaction.

Trimodal therapy consisting of neoadjuvant chemoradiation followed by esophagectomy has become the standard of care in North America for locally advanced esophageal cancer. While cisplatin/5-fluorouracil has been a common concurrent chemotherapy regimen since the 1980s, its utilization has declined in recent years as the Chemoradiotherapy for Oesophageal Cancer Followed by Surgery Study (CROSS) trial regimen of carboplatin/paclitaxel has become widely adopted. The efficacy of the CROSS regimen compared to alternate chemotherapy choices, however, has rarely been evaluated when each is used as a component of a trimodal treatment approach. The aim of this study is to report our institutional experience with these two concurrent chemotherapy regimens at a specialized esophageal cancer center. We performed an Institutional Review Board-approved retrospective review of a prospectively maintained institutional foregut registry from a single National Cancer Institute-designated cancer center. Esophageal cancer patients who completed trimodal therapy with a chemotherapy regimen of either carboplatin/paclitaxel or cisplatin/5-fluorouracil were identified and divided into groups based on their chemotherapy regimens. Multivariable logistic regression was used to analyze pathologic complete response rates, while the Kaplan-Meier and Cox proportional hazards models were utilized to evaluate recurrence-free and overall survival. Analytical models were adjusted for age, clinical stage, radiation dose, histologic subtype (adenocarcinoma vs. squamous cell carcinoma), and time interval from completion of neoadjuvant therapy to surgery. One hundred and forty-two patients treated between January of 2000 and July of 2015 were identified as meeting inclusion criteria. Of this group, 87 had received the CROSS regimen of carboplatin/paclitaxel, while 55 had completed cisplatin/5-fluorouracil. Multivariable analysis demonstrated that the cisplatin/5-fluorouracil.group had an increased odds of pathologic complete response (odds ratio = 2.68, 95% confidence interval, P = 0.032), as well as significantly improved recurrence-free survival (hazard ratio = 0.39, 95% confidence interval 0.21-0.73, P = 0.003) and overall survival (hazard ratio = 0.46, 95% confidence interval 0.24-0.87, P = 0.016), compared to the carboplatin/paclitaxel group. Concurrent chemotherapy with cisplatin/5-fluorouracil in locally advanced esophageal cancer is associated with higher rates of pathologic complete response and improved recurrence-free and overall survival compared to the CROSS regimen of carboplatin/paclitaxel. This suggests that, for select patients, alternate neoadjuvant chemotherapy approaches, such as cisplatin/5-fluorouracil, merit reconsideration as potential primary treatment choices in the management of this highly morbid disease. [ABSTRACT FROM AUTHOR]

Trimodality therapy for resectable esophageal and gastroesophageal junction cancers utilizing preoperative radiotherapy with concurrent carboplatin and paclitaxel-based chemotherapy is being increasingly utilized secondary to the results of the phase III CROSS trial. However, there is a paucity of reports of this regimen as a component of chemoradiotherapy in North America. We aim to report on our clinical experience using a modified CROSS regimen with higher radiotherapy doses. Patients with advanced ( cT2- cT4 or node positive) esophageal or gastroesophageal junction carcinoma who received preoperative carboplatin/paclitaxel-based chemoradiotherapy with radiation doses of greater than 41.4 Gray ( Gy) followed by esophagectomy were identified from an institutional database. Patient, imaging, treatment, and tumor response characteristics were analyzed. Twenty-four patients were analyzed. All but one tumor had adenocarcinoma histology. The median radiation dose was 50.4 Gy. Pathologic complete response was achieved in 29% of patients, with all receiving 50.4 Gy. Three early postoperative deaths were seen, due in part to acute respiratory distress syndrome and all three patients received 50-50.4 Gy. With a median follow-up of 9.4 months (23 days-2 years), median survival was 24 months. Trimodality therapy utilizing concurrent carboplatin/paclitaxel with North American radiotherapy doses appeared to have similar pathologic complete response rates compared with the CROSS trial, but may be associated with higher toxicity. Although the sample size is small and further follow-up is necessary, radiation doses greater than 41.4 Gy may not be warranted secondary to a potentially increased risk of severe radiation-induced acute lung injury. [ABSTRACT FROM AUTHOR]

This study aimed to determine the impact of preoperative staging on the treatment of clinical T2 N0 (c T2 N0) esophageal cancer patients undergoing esophagectomy. We reviewed a retrospective cohort of 27 patients treated at a single institution between 1999 and 2011. Clinical staging was performed with computed tomography, positron emission tomography, and endoscopic ultrasound. Patients were separated into two groups: neoadjuvant therapy followed by surgery ( NEOSURG) and surgery alone ( SURG). There were 11 patients (41%) in the NEOSURG group and 16 patients (59%) in the SURG group. In the NEOSURG group, three of 11 patients (27%) had a pathological complete response and eight (73%) were partial or nonresponders after neoadjuvant therapy. In the SURG group, nine of 16 patients (56%) were understaged, 6 (38%) were overstaged, and 1 (6%) was correctly staged. In the entire cohort, despite being clinically node negative, 14 of 27 patients (52%) had node-positive disease (5/11 [45%] in the NEOSURG group, and 9/16 [56%] in the SURG group). Overall survival rate was not statistically significant between the two groups ( P = 0.96). Many c T2 N0 patients are clinically understaged and show no preoperative evidence of node-positive disease. Consequently, neoadjuvant therapy may have a beneficial role in treatment. [ABSTRACT FROM AUTHOR]

We synthesized CdSe/CdS giant-shell nanocrystals, with a CdSe core diameter between 2.8 nm and 5.5 nm, and a CdS shell thickness of up to 7–8 nm (equivalent to about 20 monolayers of CdS). Both the core and shell have a wurtzite crystal structure, yielding epitaxial growth of the shell and nearly defect-free crystals. As a result, the photoluminescence (PL) quantum efficiency (QE) is as high as 90%. Quantitative PL measurements at various excitation wavelengths allow us to separate the nonradiative decay into contributions from interface and surface trapping, giving us pathways for future optimization of the structure. In addition, the NCs do not blink, and the giant shell and concurring strong electron delocalization efficiently suppress Auger recombination, yielding a biexciton lifetime of about 15 ns. The corresponding biexciton PL QE equals 11% in 5.5/18.1 nm CdSe/CdS. Variable-temperature time-resolved PL and PL under magnetic fields further reveal that the emission at cryogenic temperature originates from a negative trion-state, in agreement with other CdSe/CdS giant-shell systems reported in the literature. [ABSTRACT FROM AUTHOR]

Abstract: We report an experimental study on the photoluminescence band peaked at 2.7eV (blue band) induced by thermal treatments in nanometric amorphous SiO2. In particular the emission dependence on the nanometric particles size as a function of their mean diameter from 7nm up to 40nm is investigated. We found that the emission amplitude increases on decreasing the particle diameter, showing a strong correlation between the blue band and the nanometric nature of the particles. By Raman spectroscopy measurements it is evidenced that the SiO2 nanoparticles matrix is significantly affected by the reduction of size. Basing on the shell-like model, these findings are interpreted assuming that the defects responsible for the photoluminescence are localized on a surface shell of the particles and not simply on their surface. In addition it is found that the generation efficiency of these defects depends on the structural properties of the SiO2 matrix in the surface shell. [Copyright &y& Elsevier]

In the present work we report an experimental investigation by electron paramagnetic resonance spectroscopy on the hyperfine structure of the E' $_\gamma$ point defect, probing the local arrangement of the network (range-II order), and by Raman spectroscopy on the D1 and D2 lines, probing mean features of the network (range-III order). Our studies, performed on a-SiO2 samples thermally treated at 1000 °C in air for different time durations, show that changes of the hyperfine structure and of the D1 and D2 lines occur in a correlated way. These results give strong evidence that the range-II and range-III order properties are intimately related to each other and that these properties are determined by the history of the material. [ABSTRACT FROM AUTHOR]

Discusses the concept of ontology and ethics in the philosophies of Hungarian Marxist philosopher Gyorgy Lukács. Correlation between the works of Lukács and the European philosophy of irrationalism in the early 1900s; Reflections on the works of philosophers Martin Heidegger and Georg Simmel; Basis of the theories proposed by French philosopher Lucien Goldmann on irrationalism.

Renewable energy systems (RES) are currently being deployed on a large scale to meet the ambitious sustainable development goals for the next decades. A higher penetration of sustainable means of power production passes through the diffusion of RES-based distributed energy systems. The hybridization of such systems and their integration with Energy Storage Systems (ESS) can help improve reliability and level the mismatch between power production and consumption. In this paper, a novel modular tool for the simulation of distributed energy systems is presented by means of its application to a case study. The considered system is composed by PV modules, ESS and heat pumps. The optimal sizing of the components for self-consumption has been obtained through an electricity production cost minimization. A comparison between two different configurations has been conducted: in the first case, the thermal load is completely satisfied by a natural gas-fired boiler, while in the latter case, part of the thermal load is satisfied by a heat pump. The results have highlighted the impact of ESS on the economics of distributed energy systems and how the investment in such systems, in conditions similar to the case study, can be more easily sustained if a share of the total energy consumption of the unit is shifted from the thermal to the electrical part.

Abstract: We report an experimental investigation by electron paramagnetic resonance (EPR) and Raman spectroscopy on a variety of amorphous silicon dioxide materials. Our study by EPR have permitted us to point out that the splitting of the primary hyperfine doublet of the center shows a relevant sample-to-sample variability, changing from ∼41.8 to ∼42.6mT in the set of materials we considered. The parallel study by Raman spectroscopy has enabled us to state that this variability is attributable to the different Si–O–Si angle characterizing the matrices of the different materials. [Copyright &y& Elsevier]

Abstract: We report an experimental investigation on the effects of thermal treatments at different temperatures (room—1270K) and for different duration (0–75h) on amorphous silica nanoparticles (fumed silica) in powder tablet form. Three types of fumed silica are considered, comprising nearly spherical particles of 40nm, 14nm and 7nm mean diameter. The experimental techniques used here are Raman and infrared absorption (IR) spectroscopy together with atomic force microscopy (AFM). Raman and IR spectra indicate that the structure of nanometer silica particles is significantly different with respect to that of a bulk silica glass. In particular, the main differences regard the positions of the IR band peaked at about 2260cm−1, the Raman R-band peaked at about 440cm−1 and the intensity of the D1 and the D2 Raman lines, related to the populations of 4- and 3-membered rings, respectively. Our data also indicate that, under thermal treatments, the structure of fumed silica samples is significantly changed, gradually relaxing towards that pertaining to ordinary bulk silica. These changes are interpreted here on the basis of the morphological information provided by the AFM measurements and assuming a two-shell structure for the fumed silica primary particles. [Copyright &y& Elsevier]