Student evaluation of teaching, social influence dynamics, and teachers' choices: An evolutionary model

AbstractThe issue of Student Evaluation of Teaching has been explored by a large literature across many decades. However, the role of social influence factors in determining teachers' responses to a given incentive and evaluation framework has been left basically unexplored. This paper makes a first attempt in this vein by considering an evolutionary game-theoretic context where teachers face a two-stage process in which their rating depends on both students' evaluation of their course and on retrospective students' evaluation of their teaching output in view of students' performance in a related follow-up course. We find that both high effort (difficult course offered) and low effort (easy course offered) outcomes may emerge, leading either to a socially optimal outcome for teachers or not, according to cases. Moreover, there may be a potential conflict between the optimal outcome for students and for teachers. We also consider possible ways to generalize our model in future research

Graminex pollen: phenolic pattern, colorimetric analysis and protective effects in immortalized prostate cells (PC3) and rat prostate challenged with LPS

Prostatitis, a general term describing prostate inflammation, is a common disease that could be sustained by bacterial or non-bacterial infectious agents. The efficacy of herbal extracts with antioxidant and anti-inflammatory effects for blunting the burden of inflammation and oxidative stress, with possible improvements in clinical symptoms, is under investigation. Pollen extracts have been previously reported as promising agents in managing clinical symptoms related to prostatitis. The aim of the present work was to evaluate the protective effects of Graminex pollen (GraminexTM, Deshler, OH, USA), a commercially available product based on standardized pollen extracts, in rat prostate specimens, ex vivo. In this context, we studied the putative mechanism of action of pollen on multiple inflammatory pathways, including the reduction of prostaglandin E2 (PGE2), nuclear factor kappa-light-chain-enhancer of activated B cells (NFB), and malondialdehyde (MDA), whose activities were significantly increased by inflammatory stimuli. We characterized by means of chromatographic and colorimetric studies the composition of Graminex pollen to better correlate the activity of pollen on immortalized prostate cells (PC3), and in rat prostate specimens challenged with Escherichia coli lipopolysaccharide (LPS). We found that Graminex pollen was able to reduce radical oxygen species (ROS) production by PC3 cells and MDA, NFB mRNA, and PGE2 levels, in rat prostate specimens. According to our experimental evidence, Graminex pollen appears to be a promising natural product for the management of the inflammatory components in the prostate

Rainfall thresholds for possible landslide occurrence in Italy

Abstract The large physiographic variability and the abundance of landslide and rainfall data make Italy an ideal site to investigate variations in the rainfall conditions that can result in rainfall-induced landslides. We used landslide information obtained from multiple sources and rainfall data captured by 2228 rain gauges to build a catalogue of 2309 rainfall events with – mostly shallow – landslides in Italy between January 1996 and February 2014. For each rainfall event with landslides, we reconstructed the rainfall history that presumably caused the slope failure, and we determined the corresponding rainfall duration D (in hours) and cumulated event rainfall E (in mm). Adopting a power law threshold model, we determined cumulated event rainfall–rainfall duration (ED) thresholds, at 5% exceedance probability, and their uncertainty. We defined a new national threshold for Italy, and 26 regional thresholds for environmental subdivisions based on topography, lithology, land-use, land cover, climate, and meteorology, and we used the thresholds to study the variations of the rainfall conditions that can result in landslides in different environments, in Italy. We found that the national and the environmental thresholds cover a small part of the possible DE domain. The finding supports the use of empirical rainfall thresholds for landslide forecasting in Italy, but poses an empirical limitation to the possibility of defining thresholds for small geographical areas. We observed differences between some of the thresholds. With increasing mean annual precipitation (MAP), the thresholds become higher and steeper, indicating that more rainfall is needed to trigger landslides where the MAP is high than where it is low. This suggests that the landscape adjusts to the regional meteorological conditions. We also observed that the thresholds are higher for stronger rocks, and that forested areas require more rainfall than agricultural areas to initiate landslides. Finally, we observed that a 20% exceedance probability national threshold was capable of predicting all the rainfall-induced landslides with casualties between 1996 and 2014, and we suggest that this threshold can be used to forecast fatal rainfall-induced landslides in Italy. We expect the method proposed in this work to define and compare the thresholds to have an impact on the definition of new rainfall thresholds for possible landslide occurrence in Italy, and elsewhere

A tool for the automatic calculation of rainfall thresholds for landslide occurrence

Abstract Empirical rainfall thresholds are commonly used to forecast landslide occurrence in wide areas. Thresholds are affected by several uncertainties related to the rainfall and the landslide information accuracy, the reconstruction of the rainfall responsible for the failure, and the method to calculate the thresholds. This limits the use of the thresholds in landslide early warning systems. To face the problem, we developed a comprehensive tool, CTRL–T ( C alculation of T hresholds for R ainfall-induced L andslides− T ool) that automatically and objectively reconstructs rainfall events and the triggering conditions responsible for the failure, and calculates rainfall thresholds at different exceedance probabilities. CTRL−T uses a set of adjustable parameters to account for different morphological and climatic settings. We tested CTRL−T in Liguria region (Italy), which is highly prone to landslides. We expect CTRL−T has an impact on the definition of rainfall thresholds in Italy, and elsewhere, and on the reduction of the risk posed by rainfall-induced landslides

Processing of Mass Spectrometry Data in Clinical Applications

n/

Elevated 8-isoprostane levels in basal cell carcinoma and in UVA irradiated skin.

Isoprostanes are prostaglandin isomers produced from the peroxidation of polyunsaturated fatty acids from the cellular membrane. They have been used as a specific index of cellular lipoperoxidation and as an indirect measure of oxidative stress. However, these molecules also present several biological activities. An oxidative environment measured as the presence of other indirect measurements of reactive oxygen species lipoperoxidation has recently been described in basal cell carcinoma, the most frequent type of non-melanoma skin cancer. This study aims to measure the levels of 8-isoprostaglandin F2α, an isoprostane widely studied in other models as a by-product of ROS-induced lipid peroxidation, in basal cell carcinoma and in UVA irradiated healthy skin. We found that 8-iso-PGF2α is present in higher levels in BCC specimens compared to healthy non sun-exposed skin, confirming previous studies on the production of lipoperoxidation in this tumor. Moreover, we demonstrated that topical pre-treatment with a compound containing vitamin E is capable of reducing 8-iso-PGF2α formation in UV irradiated skin suggesting a role for isoprostanes in UV induced inflammation and eventually carcinogenesis and confirming the function of vitamin E as an antioxidant in this model

airbrush spray coating of amorphous titanium dioxide for inverted polymer solar cells

One of the main topics of organic photovoltaics manufacturing is the need for simple, low cost, and large area compatible techniques. Solution-based processes are the best candidates to achieve this aim. Among these, airbrush spray coating has successfully applied to deposit both active and PEDOT layers of bulk-heterojunction solar cells. However, this technique is not yet sufficiently studied for interfacial layers (electron and hole transporting layers or optical spacers). In this paper, we show that amorphous titanium dioxide ( ) films, obtained with an airbrush from a solution of titanium (IV) isopropoxide diluted in isopropanol, are successfully deposited on glass and PET substrates. Good surface covering results from the coalescence of droplets after optimizing the spray coating system. Simple inverted polymer solar cells are fabricated using as electron transporting layer obtaining encouraging electrical performances ( % on glass/FTO and 0.7% on PET/ITO substrates)

Gastrinomas and non-functioning pancreatic endocrine tumors in multiple endocrine neoplasia syndrome type-1 (MEN-1)

Purpose: Illustrate imaging findings of gastrinomas and non-functioning pancreatic endocrine tumors (NF-PNET) in a patient with multiple endocrine neoplasia type-1 (MEN-1) syndrome with a radiologic-pathologic correlation for both along with the results of a 13 yrs observational study. Methods: A 48 yrs old male patient with MEN-1 and a Zollinger-Ellison syndrome was submitted to a duodeno-cephalopancreatectomy (DCP) extended to the pancreatic body to remove several gastrinomas shown by an endoscopic-ultrasonography as well as a large (> 2 cm) hypo-vascular pancreatic nodule shown by a contrast-enhanced multi-detector CT (CE-MDCT). Further conventional (CT/MR) and functional imaging (68Ga-PET-DOTA-TOC) studies were performed over the next 13 years. Results: Up to 14 gastrin-positive NET-G1 (pT2,N1) as well as a single PNET-G2 (pT2,N0) were found at histo-pathology which also showed a NET-G1 in the uncinate process where CE-MDCT documented a 9 mm hyper-vascular nodule. A 7 mm pancreatic nodule with identical contrast-enhancement pattern was also shown at the level of the pancreatic tail which was left to preserve endocrine function. At this level, follow-up studies documented the occurence of a small (< 1 cm) hypo-vascular nodule which was metastatic at presentation and rapidly progressed under somastatin-analogs therapy whereas the hyper-vascular nodule remained stable over 13 years. Both the pancreatic lesion as well as the hepatic metastasis showed pathologic uptake of the radiotracer with a SUVmax of 6.3 and 29.5, respectively, allowing the patient to be scheduled for a Peptide Receptor Radionuclide Therapy performed with 29.6 GBq of 177Lu-Oxotreotide. Conclusions: Contrast-enhancement patterns are correlated with both the histological grade as well as the biological behaviour of PNETS

Room-temperature metal stamping by microfluidics

We show the possibility to fabricate highly controlled metal micropatterns on a variety of substrates, such as semiconducting or metallic materials, exploiting a combination of spontaneous galvanic displacement reactions with microfluidics. The process is reliable and quite versatile and allows the fabrication of complex patterns of different metals on a number of substrates in few minutes on a conventional laboratory bench

Cadmium tolerance and phytochelatin content of Arabidopsis seedlings over-expressing the phytochelatin synthase gene AtPCS1

Previous studies demonstrated that expression of the Arabidopsis phytochelatin (PC) biosynthetic gene AtPCS1 in Nicotiana tabacum plants increases the Cd tolerance in the presence of exogenous glutathione (GSH). In this paper, the Cd tolerance of Arabidopsis plants over-expressing AtPCS1 (AtPCSox lines) has been analysed and the differences between Arabidopsis and tobacco are shown. Based on the analysis of seedling fresh weight, primary root length, and alterations in root anatomy, evidence is provided that, at relatively low Cd concentrations, the Cd tolerance of AtPCSox lines is lower than the wild type, while AtPCS1 over-expressing tobacco is more tolerant to Cd than the wild type. At higher Cd concentrations, Arabidopsis AtPCSox seedlings are more tolerant to Cd than the wild type, while tobacco AtPCS1 seedlings are as sensitive as the wild type. Exogenous GSH, in contrast to what was observed in tobacco, did not increase the Cd tolerance of AtPCSox lines. The PC content in wild-type Arabidopsis at low Cd concentrations is more than three times higher than in tobacco and substantial differences were also found in the PC chain lengths. These data indicate that the differences in Cd tolerance and in its dependence on exogenous GSH between Arabidopsis and tobacco are due to species-specific differences in the endogenous content of PCs and GSH and may be in the relative abundance of PCs of different length