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Monitoring systems have become increasingly prevalent in order to increase the safety of elderly people who live alone. These systems are designed to raise alerts when adverse events are detected, which in turn enables family and carers to take action in a timely manner. However, monitoring systems typically suffer from two problems: they may generate false alerts or miss true adverse events.This motivates the two user studies presented in this paper: (1) in the first study, we investigate the effect of the performance of different monitoring systems, in terms of accuracy and error type, on users’ trust in these systems and behaviour; and (2) in the second study, we examine the effect of recommendations made by an advisor agent on users’ behaviour.Our user studies take the form of a web-based game set in a retirement village, where elderly residents live in smart homes equipped with monitoring systems. Players, who “work” in the village, perform a primary task whereby they must ensure the welfare of the residents by attending to adverse events in a timely manner, and a secondary routine task that demands their attention. These conditions are typical of a retirement setting, where workers perform various duties in addition to keeping an eye on a monitoring system.Our main findings pertain to: (1) the identification of user types that shed light on users’ trust in automation and aspects of their behaviour; (2) the effect of monitoring-system accuracy and error type on users’ trust and behaviour; (3) the effect of the recommendations made by an advisor agent on users’ behaviour; and (4) the identification of influential factors in models that predict users’ trust and behaviour. The studies that yield these findings are enabled by two methodological contributions: (5) the game itself, which supports experimentation with various factors, and a version of the game augmented with an advisor agent; and (6) techniques for calibrating the parameters of the game and determining the recommendations of the advisor agent.

The Asmari reservoir in Haftkel field is one of the most prolific naturally fractured reservoirs in the Zagros folded zone in the southwest of Iran. The primary production was commenced in 1928 and continued until 1976 with a plateau rate of 200,000 bbl/day for several years. There was an initial gas cap on the oil column. Gas injection was commenced in June 1976 and so far, 28% of the initial oil in place have been recovered. As far as we concerned, fracture network is a key factor in sustaining oil production; therefore, it needs to be characterized and results be deployed in designing new wells to sustain future production. Multidisciplinary fracture evaluation from well to reservoir scale is a great privilege to improve model’s accuracy as well as enhancing reliability of future development plan in an efficient manner. Fracture identification and modeling usually establish at well scale and translate to reservoir using analytical or numerical algorithms with the limited tie-points between wells. Evaluating fracture network from production data can significantly improve conventional workflow where limited inter-well information is available. By incorporating those evidences, the fracture modeling workflow can be optimized further where lateral and vertical connectivity is a concern. This paper begins with the fracture characterization whereby all available data are evaluated to determine fracture patterns and extension of fracture network across the field. As results, a consistent correlation is obtained between the temperature gradient and productivity of wells, also convection phenomenon is confirmed. The findings of this section help us in better understanding fracture network, hydrodynamic communication and variation of temperature. Fracture modeling is the next step where characteristics of fractures are determined according to the structural geology and stress directions. Also, the fault’s related fractures and density of fractures are determined. Meanwhile, the results of data evaluation are deployed into the fracture model to control distribution and characteristics of fracture network, thereby a better representation is obtained that can be used for evaluating production data and optimizing development plan.

Purpose To evaluate the value of dual-phase parenchymal blood volume (PBV) C-arm mounted cone-beam-CT (CBCT) to enable assessment of radiopaque, doxorubicin-loaded drug-eluting embolics (rDEE) based on the visual degree of embolization, embolic density and residual tumor perfusion as early predictors for tumor recurrence after transarterial chemoembolization (TACE) of hepatocellular carcinoma (HCC). Material and Methods Thirty patients (50 HCCs) were prospectively enrolled, underwent cross-sectional imaging before and after TACE using 100–300 µm rDEE and had regular follow-up examinations. Directly before and after the TACE procedure, PBV-CBCT was acquired. The response was evaluated and compared to visual degree of embolization (DE) and embolic density (ED) of rDEE deposits, as well as the presence of residual tumor perfusion (RTP) derived from PBV-CBCT. Outcome was assessed by mid-term tumor response applying mRECIST and patient survival after 12 months. Results RTP was detected in 16 HCCs and correlated negatively with DE (p = .03*) and ED (p = .0009*). The absence of RTP significantly improved lesion-based mid-term response rates regarding complete response (CR, 30/34 (88%) vs 2/16 (12.5%), p = .0002*), lesion-based complete response rate was 75% (21/28) for DE ≥ 50% vs. 50% (11/22) for DE p = .08) and 82% (27/33) for ED ≥ 2 vs. 29% for ED p = .005*). Thirteen patients were treated with re-TACE within 12 months, 11 of which had shown RTP. 12-month survival rate was 93%. Conclusion Residual tumor perfusions as assessed by PBV-CBCT during rDEE-TACE proved to be the best parameter to predict mid-term response. “Level of Evidence: Level 3”

This paper presents a novel point of view for the performance investigation and optimization of energy absorber devices, which is numerically introduced using the finite element method employing corrugated tubes. The numerical results show that structural or material softening leads to an optimal configuration at which the corrugated or circular tube achieves its peak performance. The performance and optimization parameters used in this study are absorbed crash energy and specific energy absorption. The force-displacement (f-d) diagram of the energy absorbers is divided into three parts for numerical investigation. The optimum point of each corrugated tube is observed when the values of energy absorption (EA) at different stages of the stroke (i.e., in the first, middle, and last portions of deformation) are almost equal or close to one another. Furthermore, the effect of material softening is discussed. The effects of cladding a ductile layer on f-d diagram, EA and deformation of thin-walled circular tubes are numerically investigated. Adding soft material layers oriented at 30° to 70° to the model can increase the performance of energy absorbers by approximately 10 % compared with the model that uses only the core material.

Hesperidin (HD), a bioflavanone glycoside, was isolated from orange peel and converted to hesperetin (HT) using a simple and efficient green procedure. Then dextran-hesperetin conjugate (Dex-HT) was prepared by free radical grafting reaction and the functionalization degree of it was assessed by the Folin–Ciocalteu method. The antioxidant activity of HD, HT and Dex-HT was tested by DPPH⋅ radical method. Presence of dextran as a backbone in the Dex-HT structure, improved antioxidant activities of the hesperetin. In addition, antimicrobial effect of these compounds was evaluated against some food pathogens (Listeria monocytogenes and Salmonella typhimurium). According to the results, L. monocytogenes was more sensitive to these compounds than S. typhimurium. Also, Dex-HT was more bacteriostatic than HD and HT. In addition, cytotoxic effect of Dex-HT against MCF-7(human breast adenocarcinoma), AGS (gastric adenocarcinoma) and normal fibroblast cells was determined in 48 and 72 h using MTT assay. The outcomes indicated that Dex-HT induced a significant dose-dependent cytotoxic effect on both AGS and MCF-7 cells. Moreover, Dex-HT showed a greater cytotoxic effect on MCF-7 cells than on AGS and normal cells. In this study, dextran, a biodegradeble carbohydrate polymer, was employed as a versatile scaffold to develop highly efficient antioxidant, antibacterial and anticancer hybrid material.

The manuscript discusses the application of CT pulmonary angiography, ventilation–perfusion scan, and magnetic resonance angiography to detect acute pulmonary embolism and to plan endovascular therapy. CT pulmonary angiography offers high accuracy, speed of acquisition, and widespread availability when applied to acute pulmonary embolism detection. This imaging modality also aids the planning of endovascular therapy by visualizing the number and distribution of emboli, determining ideal intra-procedural catheter position for treatment, and signs of right heart strain. Ventilation–perfusion scan and magnetic resonance angiography with and without contrast enhancement can also aid in the detection and pre-procedural planning of endovascular therapy in patients who are not candidates for CT pulmonary angiography.

Urban facilities within a neighborhood are among the most important factors affecting residential satisfaction. According to the definitions of neighborhood by different scholars, initial impression is that the facilities whose service scope exceeds the border of the neighborhood (cross-neighborhood facilities) can be considered as a source of citizens’ dissatisfaction. However, it seems that such facilities can also be associated with potential positive effects for residents. This study tries to assess residential satisfaction regarding different cross-neighborhood facilities in Jahanshar neighborhood (Karaj, Iran) through the existing methods in order to solve this paradox that the existence of cross-neighborhood facilities inside a neighborhood will ultimately lead to residents’ satisfaction or not. To this end, required data was collected through documentary studies and field operations including interview and questionnaire. Sample size of 377 was determined using the Cochran formula and the questionnaires were randomly distributed among the residents living in the neighborhood. A conceptual model was presented and Importance-Satisfaction Analysis was selected. Nevertheless, since the method was found to have limitations, it was improved by Fuzzy Analytical Hierarchy Process for a more accurate evaluation. The results indicate that contrary to initial impression, the existence of cross neighborhood facilities within a neighborhood does not always have negative impacts on resident’s satisfaction. Despite some dissatisfactions which must be considered by decision makers using the results of this study, there are the areas where these facilities promoted the residents’ quality of life.

Despite appropriate design of girder under bending and shear, the deflection of long steel girders usually exceeds the allowable range, and therefore the structural designers encounter challenges in this regard. Considering significant features of the cables, namely, low weight, small cross section, and high tensile strength, they are used in this research so as to control the deflection of long girder bridges, rather than increasing their heights. In this study, theoretical relations are developed to calculate the increase in pre-tensioning force of V-shaped steel cables under external loading as well as the deflection of steel girder bridges with V-shaped cables and different support conditions. To verify the theoretical relations, the steel girder bridge is modeled in the finite element ABAQUS software with different support conditions without cable and with V-shaped cables. The obtained results show that the theoretical relations can appropriately predict the deflection of girder bridge with V-shaped cables and different support conditions. In this study, the effects of the distance from support on the deflection of mid span are studied in both simply supported and fixed supported girder bridge so as to obtain the appropriate distance from support causing the minimum deflection.

Small bowel transplant (SBT) is a surgical procedure that may be used in patients with pathology resulting in severe intestinal failure resistant to conventional forms of surgical and nonsurgical treatment. Intestinal failure is defined as the failure of enterocytes to absorb sufficient macronutrients, water, and/or electrolytes to sustain homeostasis and/or promote growth. With the advancement of surgical techniques and advancements in perioperative transplant management, SBT has become an increasingly common treatment for intestinal failure, with survival rates for SBT comparable to those for other solid organ transplants. This review provides background on SBT, its variations, and the associated preoperative and postoperative imaging studies with regard to surgical planning and anticipated complications. With the increasing use of SBT, radiologists will be expected to be familiar with the diagnostic studies and available endovascular interventions associated with this procedure.

In this report, design and assembly of a simple, easy-to-make and low-cost piezoelectric actuator (PZA) with one degree of freedom for application in phase-shifting interferometry is described. The PZA is designed in a way that its components can easily be manufactured and assembled. In the developed PZA, a series of ring-shaped piezo-ceramics are assembled inside a stainless steel case and through a couple of plate springs are preloaded. Planar electrodes are cut from a thin beryllium copper plate using wire-cut EDM and used on top and bottom sides of each ceramic plate. The supply voltage is applied to the electrodes by a designed control electronic circuit connected directly to a computer through a standard parallel port. A graphical user interface is developed in the MATLAB environment for controlling the converter. The electromechanical response of the PZA is studied by applying a calibration procedure based on using a Michelson interferometer. It is shown that by increasing the DC voltage from 0 to 200 V, the PZA has a good linear response. By using the PZA for strain field measurement in a rectangular steel plate, it is shown that the linear response of the designed PZA makes it a suitable candidate for use in Carre phase-shifting interferometry.

Multi-energy computed tomography (MECT) refers to acquisition of CT data at multiple energy levels (typically two levels) using different technologies such as dual-source, dual-layer and rapid tube voltage switching. In addition to conventional/routine diagnostic images, MECT provides additional image sets including iodine maps, virtual non-contrast images, and virtual monoenergetic images. These image sets provide tissue/material characterization beyond what is possible with conventional CT. MECT provides invaluable additional information in the evaluation of pulmonary vasculature, primarily by the assessment of pulmonary perfusion. This functional information provided by the MECT is complementary to the morphological information from a conventional CT angiography. In this article, we review the technique and applications of MECT in the evaluation of pulmonary vasculature.

To assess the diagnostic accuracy of automated 3D volumetry of central pulmonary arteries using computed tomography pulmonary angiography (CTPA) for suspected pulmonary hypertension alone and in combination with echocardiography.This retrospective diagnostic accuracy study included 70 patients (mean age 66.7, 48 female) assessed for pulmonary hypertension by CTPA and transthoracic echocardiography with estimation of the pulmonary arterial systolic pressure (PASP). Gold standard right heart catheterisation with measurement of the invasive mean pulmonary arterial pressure (invasive mPAP) served as the reference. Volumes of the main, right and left pulmonary arteries (MPA, RPA and LPA) were computed using automated 3D segmentation. For comparison, axial dimensions were manually measured. A linear regression model was established for prediction of mPAP (predicted mPAP).MPA, RPA and LPA volumes were significantly increased in patients with vs. without pulmonary hypertension (all p 0.001). Of all measures, MPA volume demonstrated the strongest correlation with invasive mPAP (r = 0.76, p 0.001). Predicted mPAP using MPA volume and echocardiographic PASP as covariates showed excellent correlation with invasive mPAP (r = 0.89, p 0.001). Area under the curves for predicting pulmonary hypertension were 0.94 for predicted mPAP, compared to 0.90 for MPA volume and 0.92 for echocardiographic PASP alone. A predicted mPAP 25.8 mmHg identified pulmonary hypertension with sensitivity, specificity, positive and negative predictive values of 86%, 93%, 95% and 81%, respectively.Automated 3D volumetry of central pulmonary arteries based on CTPA may be used in conjunction with echocardiographic pressure estimates to noninvasively predict mPAP and pulmonary hypertension as confirmed by gold standard right heart catheterisation with higher diagnostic accuracy than either test alone.• This diagnostic accuracy study derived a regression model for noninvasive prediction of invasively measured mean pulmonary arterial pressure as assessed by gold standard right heart catheterisation. • This regression model using automated 3D volumetry of the central pulmonary arteries based on CT pulmonary angiography in conjunction with the echocardiographic pressure estimate predicted pulmonary arterial pressure and the presence of pulmonary hypertension with good diagnostic accuracy. • The combination of automated 3D volumetry and echocardiographic pressure estimate in the regression model provided superior diagnostic accuracy compared to each parameter alone.

Heart failure is a clinical condition that is associated with significant morbidity and mortality. With the advent of left ventricular assist device (LVAD), an increasing number of patients have received an artificial heart both as a bridge-to-therapy and as a destination therapy. Clinical trials have shown clear survival benefits of LVAD implantation. However, the increased survival benefits and improved quality of life come at the expense of an increased complication rate. Common complications include perioperative bleeding, infection, device thrombosis, gastrointestinal bleeding, right heart failure, and aortic hemodynamic changes. The LVAD-associated complications have unique pathophysiology. Multiple imaging modalities can be employed to investigate the complications, including computed tomography (CT), positron emission tomography-computed tomography (PET-CT), catheter angiography and echocardiography. Imaging studies not only help ascertain diagnosis and evaluate the severity of disease, but also help direct relevant clinical management and predict prognosis. In this article, we aim to review the common LVAD complications, present the associated imaging features and discuss the role of imaging in their management.

Background This study aimed to reflect on scientific experts’ and executive stakeholders’ opinions on how charitable organizations can participate in the health care system properly and cope with problems, challenges, strategies, and executive requirements at three major levels of prevention, treatment, and rehabilitation. Methods A total number of 20 semi-structured interviews were conducted with scientific experts and executive stakeholders, selected for this qualitative study, based on an interview guide. Using the purposeful sampling method, we selected scientific experts with 5 years of experience in the health care system and executive stakeholders who had 5 years of experience in charitable activities. We applied a framework method for data analysis, and the main themes were extracted through MAXQDA software. Results Our findings revealed that charitable organizations at the major levels of the health care system, i.e., prevention, treatment, and rehabilitation, possessed the necessary capacities to provide services effectively. Nevertheless, charities encountered some problems, e.g., financial instability, non-recognition of donors’ legal status, non-involvement in policy-making, inadequate cooperation from other agencies, absence of transparent programs and goals, together with weaknesses in advertising and attracting donations. It was noted that the government should take more operational steps towards supporting such organizations, e.g., by granting special facilities and exemptions, engaging charities in policy-making and training processes, and empowering them in terms of the production of resources. Charitable organizations are also recommended to establish external communications with other bodies such as municipalities, secretaries of state, governorate offices, welfare organizations, relief committees, and medical sciences universities. Conclusions Charitable organizations have the potentials to provide health care services at prevention, treatment, and rehabilitation levels. Thus, it is of utmost importance to adopt strategies such as creating sustainable funding sources, training charity managers with a wide variety of scientific management techniques, and implementing their intellectual capacities in legislative and planning processes.

The effect of material property variation on ductility and fracture strain in functionally graded materials (FGMs) is investigated using the finite element method (FEM) and the Gurson–Tvergaard–Needleman (GTN) model, which is strain-controlled for void nucleating. The material properties of FGMs in the tensile tests are assumed to be represented by a power-law distribution in the thickness direction. A gradation index (n) assigns the material property distribution. The lower and upper surfaces are pure hard (n = ∞) and pure soft (n = 0) materials, respectively, in the simulations. The ductility and fracture strain changes with varying gradation index. The development of stress triaxiality slows down in FGMs, and the total void volume fraction is reduced. The analysis is performed for five values of n, and the results are discussed numerically. The aim of this study is to help the researchers for better design and fabrication of FGMs. The necking strain in FGMs is calculated and it is found that it increases when the rate of hardening in the effective stress–strain curve increases. Lastly, it can be concluded that gradation index has significant effect on the elastic–plastic and fracture behavior of the functional graded (FG) specimen.

This paper presents results from a web-based study that investigates users’ attitudes toward smart devices, focusing on acceptability. Specifically, we conducted a survey that elicits users’ ratings of devices in isolation and devices in the context of tasks potentially performed by these devices. Our study led to insights about users’ attitudes towards devices in isolation and in the context of tasks, and about the influence of demographic factors and factors pertaining to technical expertise and experience with devices on users’ attitudes. The insights about users’ attitudes provided the basis for two recommendation approaches based on principal components analysis (PCA) that alleviate the new-user and new-item problems: (1) employing latent features identified by PCA to predict ratings given by existing users to new devices, and by new users to existing devices; and (2) identifying a relatively small set of key questions on the basis of PCs, whose answers account to a large extent for new users’ ratings of devices in isolation and in the context of tasks. Our results show that taking into account latent features of devices, and asking a relatively small number of key questions about devices in the context of tasks, lead to rating predictions that are significantly more accurate than global and demographic predictions, and substantially reduce prediction error, eventually matching the performance of strong baselines.

The hematological side effects associated with mycophenolic acid (MPA) are relatively common and have severe consequences. The majority of literature data have not shown clear consistency in the MPA exposure-neutropenia relationship. We hypothesized that (i) adult de novo kidney transplant recipients who develop neutropenia have relatively higher dose-normalized MPA exposure than patients without neutropenia, and (ii) the observed neutropenia may be explained by polymorphisms in metabolism and/or transporter genes responsible for MPA disposition. Adult kidney transplant recipients on steady-state tacrolimus and MPA, not receiving a corticosteroid, and with stable renal function were recruited for investigation at three periods post-transplant (1, 3, and 12 months; n = 21, 17, and 13, respectively). Clinical variables (age, weight, MPA daily dose, albumin, serum creatinine, absolute neutrophil count), tacrolimus and MPA concentrations (for exposure calculation), and genotypes (UGT2B7 G211T, UGT2B7 C802T, UGT1A9 T-275A, UGT1A9 T98C, MRP2 C-24T, MRP2 G1249A, OATP1B1 A388G, OATP1B1 C463A) were characterized. A significant inverse association between dose-normalized MPA exposure (a surrogate marker for apparent MPA clearance) and absolute neutrophil count in all three study periods (r2 ~ 0.3–0.7) was observed. No associations between characterized single nucleotide polymorphisms and MPA exposure or absolute neutrophil count were established. However, significant alterations in the minor allele frequencies of UGT2B7*2 C802T, UGT1A9 T275A, and MRP2 G1249A were evident. These findings support the clinical strategy for conducting MPA therapeutic drug monitoring in adult kidney transplant patients on steroid-free immunosuppressant therapy. The novel population genomic analysis data warrant further epidemiological investigations in a larger study sample.