Co‐delivery of methotrexate and doxorubicin via nanocarriers of star‐like poly(DMAEMA‐block‐HEMA‐block‐AAc) terpolymers

Combined therapy is a promising strategy for clinical cancer treatment with synergistic effects. The purpose of the work reported was to evaluate a smart nanocarrier for co‐delivery of doxorubicin (DOX) and methotrexate (MTX). Since star‐like nanocarriers can load a high dose of drugs with various properties, we developed star polymer nanomicelles based on poly[(2,2‐dimethylaminoethyl methacrylate)‐block‐(2‐hydroxyethyl methacrylate)‐block‐(acrylic acid)] having potential for multi‐drug delivery. The nanomicelles demonstrated high encapsulation efficiency, i.e. 97.1% for DOX and 79.5% for MTX. To this end, the star‐like terpolymers were synthesized via atom transfer radical polymerization with pentaerythritol as an initiator. The micellar properties and dual stimuli‐responsive behaviour of the terpolymers were investigated using transmission electron microscopy, field emission scanning electron microscopy and dynamic light scattering measurements, concluding that this co‐therapy offers a promising approach for cancer treatment. © 2019 Society of Chemical Industry     

T-Stress Effects on Isochromatic Fringe Patterns in Mode II

The theory of photoelasticity is used to study analytically the effects of T-stress on the fringe patterns around the crack tip in mode II crack specimens. The locus of an isochromatic fringe determined by taking into account the T-stress is compared with the locus of a fringe with no T-stress. It is shown for mode II cracks that in the presence of T-stress, the fringe loops are neither symmetric nor continuous. Asymmetric and discontinuous fringe patterns predicted in this paper are consistent with the experimental results observed previously in photoelasticity tests.     

Effect of aberrations and scatter on image resolution assessed by adaptive optics retinal section imaging

The effect of increased high-order wavefront aberrations on image resolution was investigated, and the performance of adaptive optics (AO) for correcting wavefront error in the presence of increased light scatter was assessed in a model eye. An AO section imaging system provided an oblique view of a model retina and incorporated a wavefront sensor and deformable mirror for measurement and compensation of wavefront aberrations. Image resolution was quantified by the width of a Lorentzian curve fitted to a laser line image. Wavefront aberrations were significantly reduced with AO, resulting in improvement of image resolution. In the model eye, image resolution was degraded with increased high-order wavefront aberrations (horizontal coma and spherical) and improved with AO correction of wavefront error in the presence of increased light scatter. The findings of the current study suggest that AO imaging systems can potentially improve image resolution in aging eyes with increased aberrations and scatter.     

Hemodialysis cost in Tehran,Iran

The purpose of this study was to assess the health service cost of hemodialysis (HD) delivered at hospitals in Iran as a developing country with a well‐defined program of renal replacement therapy. A cost analysis was performed from the viewpoint of the 2 hospitals, with 3 shifts and full chairs, on current practice for dialysis maintenance. Cost and patient data were collected in 2006 and from April 1 to May 31, 2007, respectively. A total of 22,464 HD sessions were performed and 247 patients were studied during the study period. The reference year for the value of USD for different mentioned costs was 2006. Health care sector costs associated with each HD session were estimated at US$78.87. Most of the total maintenance expenditure was made up of medical supplies (36.19%), with dialyzers as the major cost driver. Staff salaries represented 17% of the cost and fixed direct capital costs accounted for 21.4%. Of the family members, 32.4% accompanied their patients. The mean cost for transportation of patients and accompanied person was US$3.15 ± 2.83 and US$1.5 ± 0.29, respectively. These findings are important in the light of limited available resources coupled with the increasing prevalence of kidney failure. A major attempt should also be made to increase peritoneal dialysis coverage as in some centers we cannot keep all chairs full, especially in some vast areas. It is highly recommended to place initial focus on strategies and treatments that slow disease progression, to postpone renal replacement therapy to save resources.     

Conflict resolution using game theory and rough sets

Conflicts occur naturally in the real world at all levels of society, individually, in groups or society as a whole. Almost all the existing conflict resolution models are unilateral in their decision‐making process. They do not consider the actions of the involved parties simultaneously. Therefore, in this paper, we aim to design a novel conflict resolution model based on game‐theoretic rough sets by constructing a game between all the concerned parties (players), computing the payoff of different strategies and classifying them following equilibrium rules. The proposed model yields more realistic and accurate results as it explores all possibilities and is flexible in determining different threshold values relative to the complexities of real‐life problems. Three real‐life conflict situations are solved with the proposed model, and a comprehensive analysis is done to validate the effectiveness of the proposed approach.     

Effect of dimensional and material property uncertainties on thermal flexure microactuator response using probabilistic methods

Micromachining of microelectromechanical systems such as other fabrication processes has inherent variation that leads to uncertain dimensional and material properties. In this paper, the effect of material and feature dimension uncertainties due to fabrication process on electrothermal microactuator tip deflection is investigated. A simple and efficient uncertainty analysis method is used based on direct linearization method (DLM); uncertainty analysis is performed by creating second-order metamodel through Box-Behnken design and Monte Carlo simulation. The standard deviations of tip deflection obtained by these two probabilistic methods are very close. Simulation results have been validated by a comparison with experimental results in literature. Experimental results fall within 95% confidence boundary obtained by DLM method. Also, sensitivity analysis of microactuator has been explored; the results show that microactuator performance has been affected more by thermal expansion coefficient and microactuator gap uncertainties.     

Modelling of evaporation from the reservoir of Yuvacik dam using adaptive neuro-fuzzy inference systems

Adaptive neuro-fuzzy inference system (ANFIS) models are proposed as an alternative approach of evaporation estimation for Yuvacik Dam. This study has three objectives: (1) to develop ANFIS models to estimate daily pan evaporation from measured meteorological data; (2) to compare the ANFIS model to the multiple linear regression (MLR) model; and (3) to evaluate the potential of ANFIS model. Various combinations of daily meteorological data, namely air temperature, relative humidity, solar radiation and wind speed, are used as inputs to the ANFIS so as to evaluate the degree of effect of each of these variables on daily pan evaporation. The results of the ANFIS model are compared with MLR model. Mean square error, average absolute relative error and coefficient of determination statistics are used as comparison criteria for the evaluation of the model performances. The ANFIS technique whose inputs are solar radiation, air temperature, relative humidity and wind speed, gives mean square errors of 0.181 mm, average absolute relative errors of 9.590% mm, and determination coefficient of 0.958 for Yuvacik Dam station, respectively. Based on the comparisons, it was found that the ANFIS technique could be employed successfully in modelling evaporation process from the available climatic data.     

Rare Earth/Metal Composite Formation by Cold Spray

Nd₂Fe₁₄B permanent magnet/aluminum composite coatings were produced by cold spray deposition. Isotropic Nd₂Fe₁₄B powder was blended with aluminum powder to make mixtures of 20-80 vol.% Nd₂Fe₁₄B, and these mixtures were sprayed at temperatures of 200-480 °C. The hard Nd₂Fe₁₄B particles tended to fracture and fragment upon impact, while aluminum underwent severe plastic deformation, eliminating pores, and trapping Nd₂Fe₁₄B within the coating. It was found that higher spray temperatures and finer Nd₂Fe₁₄B particle sizes improved the retention rate of Nd₂Fe₁₄B within the composite structure. This was explained from a contact mechanics viewpoint by calculating the effect of process parameters on the rebound momentum of Nd₂Fe₁₄B particles. The magnetic properties of Nd₂Fe₁₄B remained unaffected by the cold spray process.