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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]

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]

Objective masticatory performance assessment using two-coloured specimens relies on image processing techniques; however, just a few approaches have been tested and no comparative studies are reported. The aim of this study was to present a selection procedure of the optimal image analysis method for masticatory performance assessment with a given two-coloured chewing gum. Dentate participants ( n = 250; 25 ± 6·3 years) chewed red-white chewing gums for 3, 6, 9, 12, 15, 18, 21 and 25 cycles (2000 samples). Digitalised images of retrieved specimens were analysed using 122 image processing methods (IPMs) based on feature extraction algorithms (pixel values and histogram analysis). All IPMs were tested following the criteria of: normality of measurements (Kolmogorov-Smirnov), ability to detect differences among mixing states ( anova corrected with post hoc Bonferroni) and moderate-to-high correlation with the number of cycles (Spearman's Rho). The optimal IPM was chosen using multiple criteria decision analysis (MCDA). Measurements provided by all IPMs proved to be normally distributed ( P < 0·05), 116 proved sensible to mixing states ( P < 0·05), and 35 showed moderate-to-high correlation with the number of cycles (|ρ| > 0·5; P < 0·05). The variance of the histogram of the Hue showed the highest correlation with the number of cycles (ρ = 0·792; P < 0·0001) and the highest MCDA score (optimal). The proposed procedure proved to be reliable and able to select the optimal approach among multiple IPMs. This experiment may be reproduced to identify the optimal approach for each case of locally available test foods. [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]

We present a study on the effects of an isothermal annealing treatment on a-SiO having a significant content of silanol hydride groups (Si-H). We examined the properties of the IR absorption bands of silanol (Si-OH) and silicon hydride groups as a function of the duration of the thermal treatment. We showed that the Si-OH and Si-H groups contents decrease in a linearly correlated way. The annealing dynamics suggest that the two species are close to each other in the amorphous network. We showed that the profile of the silanol groups absorption band is the same as that observed in other commercial a-SiO materials, irrespectively of the concomitant presence of nearby Si-H groups, and, moreover, it does not change during the annealing treatment. This set of evidences supports the conclusion that silanol groups are organized in clusters in the a-SiO network. Finally, present data provide an unprecedented characterization of the Si-H IR absorption band. It results that the profiles of the IR and Raman activities of silicon hydride groups closely coincide. [ABSTRACT FROM AUTHOR]

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]