Energy consumption management in Smart Homes: An M-Bus communication system

Energy consumption management in Smart Home environments relies on the implementation of systems of cooperative intelligent objects named Smart Meters. In order for devices to cooperate to smart metering applications' execution, they need to make their information available. In this paper we propose a framework that aims at managing energy consumption of controllable appliances in groups of Smart Homes belonging to the same neighbourhood or condominium. We consider not only electric power distribution, but also alternative energy sources such as solar panels. We define a communication paradigm based on M-Bus for the acquisition of relevant data by managing nodes. We also provide a lightweight algorithm for the distribution of the available alternative power among houses. Performance evaluation of experiments in simulation mode prove that the proposed framework does not jeopardise the lifetime of Smart Meters, particularly in typical situations where managed devices do not continuously turn on and off

Universal charts for optical difference frequency generation in the terahertz domain

We present a universal and rigorous approach to study difference frequency generation in the terahertz domain, keeping the number of degrees of freedom to a minimum, through the definition of a suitable figure of merit. The proposed method relies on suitably normalized charts, that enable to predict the optical-to-terahertz conversion efficiency of any system based on wave propagation in quadratic nonlinear materials. The predictions of our approach are found to be in good agreement with the best experimental results reported to date, enabling also to estimate the d22 nonlinear coefficient of high quality GaSe.Comment: 3 pages in 2 columns format, 3 figures. GaSe analysis has been corrected. Fig. 3 has been replace

The role of nonlinear optical absorption in narrow-band difference frequency terahertz-wave generation

We present a general analysis of the influence of nonlinear optical absorption on terahertz generation via optical difference frequency generation, when reaching for the quantum conversion efficiency limit. By casting the equations governing the process in a suitably normalized form, including either two-photon- or three-photon-absorption terms, we have been able to plot universal charts for phase matched optical-to-terahertz conversion for different values of the nonlinear absorption coefficients. We apply our analysis to some experiments reported to date, in order to understand to what extent multiphoton absorption could have played a role and also to predict the maximum achievable conversion efficiency at higher peak pump intensities.Comment: 16 pages, 2 figures. Some correction and some explanation adde

Automated generation of flat tileable patterns and 3D reduced model simulation

The computational fabrication community is developing an increasing interest in the use of patterned surfaces, which can be designed to show ornamental and unconventional aesthetics or to perform as a proper structural material with a wide range of features. Geometrically designing and controlling the deformation capabilities of these patterns in response to external stimuli is a complex task due to the large number of variables involved. This paper introduces a method for generating sets of tileable and exchangeable flat patterns as well as a model-reduction strategy that enables their mechanical simulation at interactive rates. This method is included in a design pipeline that aims to turn any general flat surface into a pattern tessellation, which is able to deform under a given loading scenario. To validate our approach, we apply it to different contexts, including real-scale 3D printed specimens, for which we compare our results with the ones provided by a ground-truth solver

Exploiting the optical quadratic nonlinearity of zincblende semiconductors for guided-wave terahertz generation: a material comparison

We present a detailed analysis and comparison of dielectric waveguides made of CdTe, GaP, GaAs and InP for modal phase matched optical difference frequency generation (DFG) in the terahertz domain. From the form of the DFG equations, we derived the definition of a very general figure of merit (FOM). In turn, this FOM enabled us to compare different configurations, by taking into account linear and nonlinear susceptibility dispersion, terahertz absorption, and a rigorous evaluation of the waveguide modes properties. The most efficient waveguides found with this procedure are predicted to approach the quantum efficiency limit with input optical power in the order of kWs.Comment: 8 pages in two columns format, 6 figures, 2 Table

Pulmonary transit time as a marker of diastolic dysfunction in Takotsubo syndrome

AIM: To evaluate the pulmonary transit time (PTT) and its derived parameters using cardiac magnetic resonance imaging (CMRI) as markers of diastolic dysfunction in Takotsubo syndrome (TS) and its relationship with transthoracic echocardiography and CMRI parameters. MATERIALS AND METHODS: Twenty-two patients with TS, who exhibited diastolic dysfunction as assessed by transthoracic echocardiography, were enrolled retrospectively and the PTT, pulmonary transit time index (PTTI), and pulmonary blood volume index (PBVI) were evaluated using first-pass CMRI. PTT was calculated as the number of cardiac cycles required for a bolus of contrast agent to move from the right ventricle (RV) to the left ventricle (LV), whereas PTTI represents the PTT interval corrected for the heart rate. Finally, PBVI was calculated as the product of PTTI, and RV stroke volume indexed for body surface area. Normal references of PTT, PTTI, and PBVI were evaluated in a cohort of 20 age- and sex-matched healthy controls. RESULTS: Compared with healthy subjects, TS patients showed significantly higher PTT, PTTI, and PBVI (p=0.0001, p=0.0001, and p=0.002, respectively). Using multivariable logistic regression, PBVI provided the best differentiation between TS and controls (AUC 0.84). PBVI was significantly associated with the index of diastolic dysfunction and left atrial strain parameters. In addition, PBVI demonstrated a significant correlation with global T2 mapping (r=0,520, p=0,019). CONCLUSION: PTT and the derived parameters, as assessed using first-pass CMRI, are potential tools for assessing LV diastolic dysfunction in patients with TS

Clinical strategies to aim an adequate safety profile for patients and effective training for surgical residents: The laparoscopic cholecystectomy model

Background Training programs for resident surgeons represent a challenge for the mentoring activity. The aim of the present study is to investigate the impact of our training program for laparoscopic cholecystectomy on patient's safety and on the modulation of the residents' exposure to clinical scenario with different grades of complexity. Material and methods This is a retrospective study based on a clinical series of laparoscopic cholecystectomy performed in a teaching hospital. Study population was grouped according to the expertise of the attending primary operator among resident surgeons. Four groups were identified: consultant (C), senior resident (SR); intermediate level resident (IR); junior resident (JR). The intraoperative and postoperative outcomes were confronted to evaluate the patient's safety profile. Results 447 patients were submitted to LC: 96 cases were operated by a C, 200 by SR, 112 by IR and 39 by JR. The mean operative time was the longest for the JR group. A statistically higher rate of conversion to open approach was registered in C and IR groups in comparison to JR and SR groups. However, in C and IR groups, patients had worse ASA score, higher BMI and more frequent past history of previous abdominal surgery, cholecystitis or pancreatitis. Overall, it was not registered any statistically significant difference among the groups in terms of length of hospital stay and prevalence of major postoperative complications. Conclusion Applying an educational model based on both graduated levels of responsibility and modulated grade of clinical complexity can guarantee an high safety profile

Advances in understanding large-scale responses of the water cycle to climate change

Globally, thermodynamics explains an increase in atmospheric water vapor with warming of around 7%/°C near to the surface. In contrast, global precipitation and evaporation are constrained by the Earth's energy balance to increase at ∼2–3%/°C. However, this rate of increase is suppressed by rapid atmospheric adjustments in response to greenhouse gases and absorbing aerosols that directly alter the atmospheric energy budget. Rapid adjustments to forcings, cooling effects from scattering aerosol, and observational uncertainty can explain why observed global precipitation responses are currently difficult to detect but are expected to emerge and accelerate as warming increases and aerosol forcing diminishes. Precipitation increases with warming are expected to be smaller over land than ocean due to limitations on moisture convergence, exacerbated by feedbacks and affected by rapid adjustments. Thermodynamic increases in atmospheric moisture fluxes amplify wet and dry events, driving an intensification of precipitation extremes. The rate of intensification can deviate from a simple thermodynamic response due to in‐storm and larger‐scale feedback processes, while changes in large‐scale dynamics and catchment characteristics further modulate the frequency of flooding in response to precipitation increases. Changes in atmospheric circulation in response to radiative forcing and evolving surface temperature patterns are capable of dominating water cycle changes in some regions. Moreover, the direct impact of human activities on the water cycle through water abstraction, irrigation, and land use change is already a significant component of regional water cycle change and is expected to further increase in importance as water demand grows with global population

Defining Configurable Virtual Reality Templates for End Users

This paper proposes a solution for supporting end users in configuring Virtual Reality environments by exploiting reusable templates created by experts. We identify the roles participating in the environment development and the means for delegating part of the behaviour definition to the end users. We focus in particular on enabling end users to define the environment behaviour. The solution exploits a taxonomy defining common virtual objects having high-level actions for specifying event-condition-Action rules readable as natural language sentences. End users exploit such actions to define the environment behaviour. We report on a proof-of-concept implementation of the proposed approach, on its validation through two different case studies (virtual shop and museum), and on evaluating the approach with expert users

Decrease in neutrophil-to-lymphocyte ratio during neoadjuvant chemotherapy as a predictive and prognostic marker in advanced ovarian cancer

Since chronic inflammation is associated with ovarian cancer growth and progression, some clinical studies have assessed the association between the pre-treatment neutrophil-to-lymphocyte ratio (NLR) and the prognosis of ovarian cancer. The purpose of this study was to assess the dynamic behavior of the NLR during the course of neoadjuvant chemotherapy (NACT) in patients with high grade serous (HGS) advanced epithelial ovarian cancer and assess its correlation with clinical response, progression free survival (PFS) and changes in other inflammatory indexes. We performed a prospective observational study on 161 patients who underwent NACT at the Department of Gynecologic Oncology, ARNAS G. Brotzu, Cagliari, between 2009 and 2019. NLR was evaluated before starting and after three cycles of NACT. Based on response after three cycles of NACT, patients were divided into two groups: responsive and non-responsive. The primary endpoint was to assess the predictive role of NLR by comparing the responsive and non-responsive patients at baseline and after three cycles of NACT. Secondary endpoints were (a) to correlate NLR with other inflammation markers (CRP, fibrinogen, ferritin, IL-6), albumin, and modified Glasgow Prognostic Score (mGPS) with NLR at baseline and after NACT; (b) to assess the association between NLR and PFS. We found that the NLR value at baseline was not associated with response to NACT, while a decrease in NLR after three cycles was correlated with a better response to NACT. Also, values of CRP, IL-6, ferritin, and mGPS after three cycles of NACT (but not at baseline) were significantly associated with clinical response. Moreover, we found that patients with a low NLR value after 3 cycles of NACT, but not at baseline, had a significantly higher PFS than patients with high NLR after 3 cycles of NACT. In conclusion, NLR change during treatment could serve as a predictive marker of response to NACT in patients with HGS advanced ovarian cancer. This allows for the early identification of non-responsive patients who will need treatment remodeling