Visit Places on YourWay: A Skyline Approach in Time-Dependent Networks

Many people take the same path every day, such as taking a specific autobahn to get home from work. However, one needs to frequently divert from this path, e.g., to visit a Point of Interest (POI) from a category like the category of restaurants or ATMs. Usually, people want to minimize not only their overall travel cost but also their detour cost, i.e., one wants to return to the known path as fast as possible. Finding such a POI minimizing both costs efficiently is highly challenging in case one considers time-dependent road networks which are the case in real-world scenarios. For such road networks time decency means the time a user needs to traverse a road, heavily depends on the user’s arrival time on that road. Prior works have several limitations, such as assuming that travel costs are coming from a metric space and do not change over time. Both assumptions hardly match real-world requirements: Just think of traffic jams at the rush hour. To overcome these limitations, we study how to solve this problem considering time-dependent road networks relying on linear skylines. Our main contribution is an efficient algorithm called STACY to find all non-dominated paths. A large-scale empirical evaluation on real-world data reveals that STACY is accurate, efficient and effective in real-world settings

Comparing Predictions of Object Movements

Estimating the future location of moving objects using different estimation models, such as linear or probabilistic models, has been investigated extensively. However, the location estimations of those models are generally not comparable. For instance, one model might return a position for some object, another one a Gaussian probability distribution, and a third one a uniform distribution. Similar issues arise for query answers. In this paper, we examine the question how estimations of different models can be compared. To do so, we propose a general model based on the central limit theorem. This allows handling different PDF-based approaches as well as models from the other groups (i.e., linear estimations) in a unified manner. Furthermore, we show how to inject privacy into the general model, a fundamental pre-requisite for user acceptance. Thus, we support well-known approaches like k-anonymity and spatial obfuscation. Based on our general model, we conduct a comprehensive experimental study considering a real-world road network; comparing models form different groups for the first time. Our results, for instance, reveal that estimation models based on individual velocity profiles are not necessarily better than models, which estimate the future location of objects only based on their direction. In more abstract terms, our general model allows comparison of estimation models that could not be compared before and gives way to build models that solve the privacy-accuracy challenge

Margins of postural stability in Parkinson’s disease: an application of control theory

Introduction: Postural instability is a restrictive feature in Parkinson’s disease (PD), usually assessed by clinical or laboratory tests. However, the exact quantification of postural stability, using stability theorems that take into account human dynamics, is still lacking. We investigated the feasibility of control theory and the Nyquist stability criterion—gain margin (GM) and phase margin (PM)—in discriminating postural instability in PD, as well as the effects of a balance-training program.Methods: Center-of-pressure (COP) data of 40 PD patients before and after a 4-week balance-training program, and 20 healthy control subjects (HCs) (Study1) as well as COP data of 20 other PD patients at four time points during a 6-week balance-training program (Study2), collected in two earlier studies, were used. COP was recorded in four tasks, two on a rigid surface and two on foam, both with eyes open and eyes closed. A postural control model (an inverted pendulum with a Proportional-integral-derivative (PID) controller and time delay) was fitted to the COP data to subject-specifically identify the model parameters thereby calculating |GM| and PM for each subject in each task.Results: PD patients had a smaller margin of stability (|GM| and PM) compared with HCs. Particularly, patients, unlike HCs, showed a drastic drop in PM on foam. Clinical outcomes and margins of stability improved in patients after balance training. |GM| improved early in week 4, followed by a plateau during the rest of the training. In contrast, PM improved late (week 6) in a relatively continuous-progression form.Conclusion: Using fundamental stability theorems is a promising technique for the standardized quantification of postural stability in various tasks

The effect of involved Aspergillus species on galactomannan in bronchoalveolar lavage of patients with invasive aspergillosis

PURPOSE: The detection of galactomannan (GM) in bronchoalveolar lavage (BAL) fluid is an important surrogate marker for the early diagnosis and therapeutic monitoring of invasive aspergillosis (IA), regardless of the involved species of Aspergillus. Here, we utilized the Platelia Aspergillus GM enzyme immunoassay (Bio-Rad) to evaluate the GM index in BAL fluid samples from patients with proven, probable or putative IA due to Aspergillusflavus versus Aspergillusfumigatus. METHODOLOGY: In a prospective study between 2009 and 2015, 116 BAL samples were collected from suspected IA patients referred to two university hospitals in Tehran, Iran. KEY FINDINGS: According to European Organization for Research and Treatment of Cancer and Mycoses Study Group and Blot criteria, 35 patients were classified as IA patients, of which 33 cases tested positive for GM above 0.5 and, among these patients, 22 had a GM index >/=1. Twenty-eight were culture positive for A. flavus and seven for A. fumigatus. The GM index for A. flavus cases was between 0.5-6.5 and those of A. fumigatus ranged from 1 to 6.5. The sensitivity and specificity of a GM index >/=0.5 in cases with A. flavus were 86 and 88 % and for A. fumigatus patients were 100 and 73 %, respectively. CONCLUSION: Overall, the mean GM index in patients with A. fumigatus (3.1) was significantly higher than those of A. flavus (1.6; P-value=0.031) and the sensitivity of GM lower for A. flavus when compared to A. fumigatus. This finding has implications for diagnosis in hospitals and countries with a high proportion of A. flavus infections

Hydrophobically associating polymers for enhanced oil recovery – Part B: A review of modelling approach to flow in porous media

Polymer flow in porous media represents an entirely different scenario compared to bulk flow analysis using viscometers. This is due to the geometry and configuration of the medium which is made up of converging-diverging flow paths. In this article, a review of the single-phase flow of hydrophobically associating polymers in porous media is presented. Hydrophobic association between these polymer chains have been reported to occur and vary under reservoir conditions (temperature, salinity, and ion concentration). However, under these conditions, the critical aggregation concentration of associating polymers has been observed to change and the extent of change is a function of the hydrophobe make-up of the polymer. The outcome of this would indicate that polymer injectivity and its oil recovery efficiency are affected. As such, an understanding of the mechanism, propagation and sustainability of these hydrophobic interactions in reservoirs remains a critical focus of research. This becomes even imperative as the in-situ rheological profile associated with the different flow regimes may be affected. A numerical approach to investigating the real-time hydrophobic interactions between associating polymer chains during flow in porous media remains the viable option. However, this would require modifying existing time-independent models to accurately predict the various flow regimes and the dispersion of associating polymers to account for hydrophobic interactions

OXAZIRIDINE (C-CH3NO), C-CH2NO RADICALS AND CL, NH2 AND METHYL DERIVATIVES OF OXAZIRIDINE; STRUCTURES AND QUANTUM CHEMICAL PARAMETERS

Oxaziridine [c-CH3NO (X1A)], c-CH2NO (X2A) radicals and Cl, NH2 and methyl derivatives of oxaziridine structures have been optimized via DFTB3LYP level of theory using 6-311++G (d, p) basis set. Population analysis had been carried out. Vertical ionization energy (VIE) and adiabatic ionization energy (AIE), Fukui indices and some quantum chemical parameters were calculated. N-O bond was determined as weakest bond in oxaziridine triangle. The effect of electron withdrawing and electron donating groups on stability of weakest bond were assessed

OXAZIRIDINE (C-CH3NO), C-CH2NO RADICALS AND CL, NH2 AND METHYL DERIVATIVES OF OXAZIRIDINE; STRUCTURES AND QUANTUM CHEMICAL PARAMETERS (Supplementary material)

Supplementary material contains Tables S1 to S9 and Figures S1 to S4

A postural control model to assess the improvement of balance rehabilitation in Parkinson's disease

Studies have shown that balance and mobility in people with Parkinson's disease (PD) can improve through rehabilitation interventions. However, until now no quantitative method investigated how these patients improve their balance control. In this study, a single inverted pendulum model with PID controller was used to describe the improvement of forty PD patients after a 12-session therapy program, and to compare their balance with twenty healthy subjects. The Center of Pressure (COP) data were recorded in seven sensory conditions - on rigid and foam surface, each with eyes open and closed, and with visual disturbance; and stance on rigid surface with attached vibrator to the Achilles tendons. From COP data four Stabilogram Diffusion Function (SDF) measures were extracted. In order to find the appropriate model parameters (three control parameters and a noise gain) from the SDF measures, first model simulations were performed to tune an artificial neural network (ANN) which relates the SDF measures to the PID parameters, and second the trained ANN was used to find the suitable PID model parameters from the experimentally recorded SDF measures. Statistical analysis revealed that patients had lower control parameters and noise gain than healthy subjects; confirming reduced control ability and sensory information in PDs. Balance rehabilitation improved the patients' clinical scores, which is reflected in the increased control parameters (particularly in foam tasks), and noise gain (in tasks on rigid surface). The presented method provides a good and sensitive measure to describe functional balance and mobility in PD.</p