Allocative efficiency and traders' protection under zero intelligence behavior

This paper studies the continuous double auction from the point of view of market engineering: we tweak a resampling rule often used for this exchange protocol and search for an improved design. We assume zero intelligence trading as a lower bound for more robust behavioral rules and look at allocative efficiency, as well as three subordinate performance criteria: mean spread, cancellation rate, and traders' protection. This latter notion measures the ability of a protocol to help traders capture their share of the competitive equilibrium profits. We consider two families of resampling rules and obtain the following results. Full resampling is not necessary to attain high allocative efficiency, but fine-tuning the resampling rate is important. The best allocative performances are similar across the two families. However, if the market designer adds any of the other three criteria as a subordinate goal, then a resampling rule based on a price band around the best quotes is superior.market engineering, trading protocols, competitive share, exchange market

Harnessing the power of digitalization in the transformer industry for sustainability

Digitalization - the subtle yet powerful force with a significant impact on the power transformer industry. We explore the practical applications of advanced digital technologies, from design and engineering to manufacturing and sustainability practices. In addition, the industry’s efforts toward standardization and professional development through digital tools are discussed

A procedure to evaluate the indoor global quality by a sub objective-objective procedure

This paper proposes two complementary procedures for assessing the indoor global comfort: the first one, prevalently objective, is based on the acquisition of microclimate measured data and computed subjective values; the second one, that is purely subjective, uses a questionnaire drawn from the ISO/DP 10551 Recommendation. An application to some lecture-halls is here showe

A case study to the Evaluation of Global Environmental Quality, concerning thermal, acoustic and atmospheric conditions of urban areas

In this paper we propose an operative procedure aimed at assessing and check the global environmental quality in the urban areas. This methodology is set up by using an ergonomic approach that analyses the interaction man-environment in terms of cause-effect and uses information and data from various sources contributing to the formation of discomfort degrees.[1-2] The representation technique by normo-grams is used for showing some applications executed along the urban territory of Palermo and allows to evaluate very simply all the parameters involved in human comfort. This paper is divided in 5 sections, after the introduction in section 2 a review of the principal simple and complex indexes is presented, in section 3 the methodology used to assess the air quality is presented and in section 4 some experimental results on some areas of Palermo are presented, finally in section 5 some conclusions are drawn.[3-4

Sustainable lighting design through the analysis of spatial and time non-uniformities in natural lighting with the metric of the information theory

The indoor visual comfort of subjects faced with indoor ambient lighting varies with the position of the subject and is not constant over time. Average performance indexes, such as the mean value of Daylight Factor and Daylight Autonomy, are commonly used to analyse lighting distribution. These indexes, however, don’t properly take into account either the spatial or the time distribution of values affecting the non-uniformity of environmental lighting. Indeed, these are limited to the definition of a mean value or to the assessment of time availability of daylighting. This paper examines spatial and temporal non-uniformities in indoor lighting as possible causes of discomfort for occupants. The goal is to propose and verify possible supplementary tools to integrate traditional methods of evaluating ambient indoor lighting Use of the entropy theory with a probabilistic approach can help to obtain more detailed information about the environment. The authors have developed a case study of several sample environments and have analysed the relationships between lighting parameters and typical indices of information theory. Results show that this approach could be a useful way for predicting possible indoor visual comfort issues and for developing a preliminary assessment to a sustainable building design

Editorial: Management and Treatment of Pilonidal Disease: 189 Years After Mayo

...Pilonidal Disease (PD) was first scientifically reported 189 years ago by Herbert Mayo, back in 1833, as a sinus containing hair follicles located in the sacrococcygeal region of a female patien

Stars caught in the braking stage in young Magellanic Clouds clusters

The color-magnitude diagrams of many Magellanic Cloud clusters (with ages up to 2 billion years) display extended turnoff regions where the stars leave the main sequence, suggesting the presence of multiple stellar populations with ages which may differ even by hundreds million years (Mackey et al. 2008, Milone et al. 2009, Girardi et al. 2011). A strongly debated question is whether such an extended turnoff is instead due to populations with different stellar rotations (Girardi et al. 2011, Goudfrooij et al. 2011, Rubele et al. 2013, Li et al. 2014). The recent discovery of a `split' main sequence in some younger clusters (about 80--400Myr) added another piece to this puzzle. The blue (red) side of the main sequence is consistent with slowly (rapidly) rotating stellar models (D'Antona et al. 2015, Milone et al. 2016, Correnti et al. 2017, Milone et al 2016), but a complete theoretical characterization of the observed color-magnitude diagram appeared to require also an age spread (Correnti et al. 2017). We show here that, in three clusters so far analyzed, if the blue main sequence stars are interpreted with models that have been always slowly rotating, they must be about 30% younger than the rest of the cluster. If they are instead interpreted as stars initially rapidly rotating, but that have later slowed down, the age difference disappears, and "braking" also helps to explain the apparent age differences of the extended turnoff. The age spreads in Magellanic Cloud clusters are a manifestation of rotational stellar evolution. Observational tests are suggested.Comment: Accepted for publication and in state of Advance Online Publication (from 24 July 2017) on Nature Astronom

Computed tomography findings of pneumatosis and portomesenteric venous gas in acute bowel ischemia.

BACKGROUND: To use more representative sample size to evaluate whether computed tomography (CT) scan evidence of the concomitant presence of pneumatosis and portomesenteric venous gas is a predictor of transmural bowel necrosis. METHODS: Data from 208 patients who were referred for a diagnosis of bowel ischemia were retrospectively reviewed. Only patients who underwent a surgical intervention following a diagnosis of bowel ischemia who also had a post-operative histological confirmation of such a diagnosis were included. Patients were split into two groups according to the presence of histological evidence of transmural bowel ischemia (case group) or partial bowel ischemia (control group). CT images were reviewed for findings of ischemia, including mural thickening, pneumatosis, bowel distension, portomesenteric venous gas and arterial or venous thrombi. RESULTS: A total of 248 subjects who underwent surgery for bowel ischemia were identified. Among the 208 subjects enrolled in our study, transmural bowel necrosis was identified in 121 subjects (case group), and partial bowel necrosis was identified in 87 subjects (control group). Based on CT findings, including mural thickening, bowel distension, pneumatosis, pneumatosis plus portomesenteric venous gas and presence of thrombi or emboli, there were no significant differences between the case and control groups. The concomitant presence of pneumatosis and porto-mesenteric venous gas showed an odds ratio of 1.95 (95%CI: 0.491-7.775, P = 0.342) for the presence of transmural necrosis. The presence of pneumatosis plus porto-mesenteric venous gas exhibited good specificity (83%) but low sensitivity (17%) in the identification of transmural bowel infarction. Accordingly, the positive and negative predictive values were 60% and 17%, respectively. CONCLUSION: Although pneumatosis plus porto-mesenteric venous gas is associated with bowel ischemia, we have demonstrated that their co-occurrence cannot be used as diagnostic signs of transmural necrosis

Obstructing left sided colorectal cancer. A retrospective single center study.

Background: In recent years, with population aging, there has been an increased number of colorectal cancer cases in elderly patients with severe occlusion symptoms. About 75% of obstructions due to malignant colorectal cancer (10-30%) occur distal to splenic flexure. Methods: The authors evaluated the best surgical therapeutic strategy to be used in cases of left-sided colorectal carcinoma in patients over 65 years old, especially considering the emergency condition, age of patients and efficacy in terms of postoperative morbidity, mortality and 5 years survival rate. Results: The management of left-sided obstructing colorectal carcinoma is controversial. Hartmann’s procedure is the best therapeutic choice in elderly patients. However, resection with intraoperative colonic wash-out and primary anastomosis has favorable outcome in low risk patients. Conclusions: A review of the literature reveals that primary resection and anastomosis for left-sided obstructing CRC is the correct therapeutic strategy in low risk patients with localized, resectable carcinoma, without peritonitis; Hartmann’s procedure should be adopted in doubtful cases and in high risk patients