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Infill parameters are significant with regard to the overall cost and saving material while printing a 3D model. When it comes to printing time, we can decrease the printing time by altering the infill, which also reduces the total process extent. Choosing the right filling parameters affects the strength of the printed model. In this research, the effect of filling density and infill pattern on the fatigue lifetime of cylindrical polylactic acid (PLA) samples was investigated with finite element modeling and analysis. This causes the lattice structure to be considered macro-scale porosity in the additive manufacturing process. Due to the need for multi-objective optimization of several functions at the same time and the inevitable sacrifice of other objectives, the decision was to obtain a set of compromise solutions according to the Pareto-optimal solution technique or the Pareto non-inferior solution approach. As a result, a horizontally printed rectangular pattern with 60% filling was preferred over the four patterns including honeycomb, triangular, regular octagon, and irregular octagon by considering the sum of mass changes and fatigue lifetime changes, and distance from the optimal point, which is the lightest structure with the maximum fatigue lifetime as an objective function with an emphasis on mass as an important parameter in designing scaffolds and biomedical structures. A new structure was also proposed by performing a structural optimization process using computer-aided design tools and also, computer-aided engineering software by Dassault systems. Finally, the selected samples were printed and their 3D printing quality was investigated using field emission scanning electron microscopy inspection. [ABSTRACT FROM AUTHOR]

This study explored spatial patterns of the 10 most prevalent cancers in north-eastern Iran. Getis-Ord G* and Anselin Local Moran's Index ‎were used for identifying ‎hotspots and local clusters. Except for breast cancer, all cancer types were more frequent among males. Cluster analysis in men showed hotspots of breast cancer in the South-West, skin cancer in the East/South-East, and brain tumours in the North. Among women, there were hotspots for skin cancer in the East and South-East, bladder cancer in the Central and East. ‎This study indicates a possible relationship between the high ‎incidence of certain cancers and environmental factors. [ABSTRACT FROM AUTHOR]

This paper presents and evaluates an application of a robust data envelopment analysis (RDEA) multi-criteria model for prioritising safety improvement projects with limited budget and data uncertainty. RDEA can be seen as an extension of classic data envelopment analysis (CDEA) that supports a more flexible and robust project selection by enabling decision-makers to adjust the level of conservation (or robustness) of decision-making against data uncertainty. Data from an existing case study were used to evaluate the performance of the model. The results indicated that the proposed methodology provides a useful tool for adjusting the level of robustness and that the efficiency of the candidate project decreases with the decision-maker's conservativeness and their ranking does not change as the decision-maker becomes more risk-averse. As a comparative study, the proposed approach was compared with incremental benefit–cost analysis and CDEA methods. The results indicated some changes in the list of selected projects considering the uncertainty impacts of data observed according to allocated budgets. [ABSTRACT FROM AUTHOR]

Highlights • An integrated DEA and Monte-Carlo simulation prioritizing approach is proposed. • It presents a ranking result by simulating uncertain environment of decision-making. • The influence of uncertainty in project prioritization problem is investigated. • Results indicate that unreliable data can have great influence in ranking results. • It provides a good tool for decision-maker to consider effects of unreliable data. Abstract Road authorities have to prioritize safety improvement projects due to budget limitations. This process needs to estimate expected benefits (reduction in average crash frequency) and costs of projects. Due to variances of crash modification factor (CMF), crash frequency and cost of projects, prediction of costs and benefits would be accompanied by uncertainty and it can subsequently lead to a wrong decision making. To deal with the inherent uncertainty in the decision making process, this paper presents a ranking approach based on integration of Data Envelopment Analysis and Monte-Carlo simulation. A Monte-Carlo simulation is applied to generate stochastic values as input and outputs of the problem instead of running DEA model just for deterministic case. Data from an existing case study is used to evaluate the performance of the proposed methodology. Numerical results indicate that DEA results are very sensitive to data uncertainty and uncertainties can have great influence in ranking results of road safety improvement projects especially when both input and output data are uncertain. It also indicates that how the proposed methodology can be useful for detecting sensitive decision-making units and providing a more comprehensive view for decision makers to allocate a limit budget to the most efficient safety improvement projects. [ABSTRACT FROM AUTHOR]

Road authorities need efficient tools to assign a limited budget to safety improvement projects. The process of prioritizing safety improvement projects needs to predict the benefits and costs of projects. In real-life situations and also because of variances of crash frequency, crash modification factor (CMF), and imposed expenses, the forecast of project costs/benefits would be highly affected by uncertainty. Hence, this work develops a model based on stochastic binary programming with robust constraints to treat the inherent uncertainties to prioritize road safety improvement projects. Robust optimization approach ensures a high probability of feasibility for the solutions obtained under uncertain conditions. Efficiency of the suggested model is assessed using data collected from a real case study. Numerical results reveal that neglecting stochastic analysis would lead to a profit loss up to 15% of the total benefits of safety plan and the importance of considering stochastic nature of the problem increases as the budget of a safety plan decreases. Furthermore, to make a comparative analysis, the developed methodology is compared with some conventional methods, e.g., integer programming model and incremental benefit–cost analysis. Main findings demonstrate some deviations concerning how each approach copes with uncertainty which leads to differences in the list of the selected projects with respect to budget limitation. Finally, the developed methodology is recommended to managers as a flexible and robust tool to assess and select projects through setting the level of robustness against cost data uncertainty, which is done according to the decision-makers’ attitudes. [ABSTRACT FROM AUTHOR]

Controlling of vital signs is crucial for patients in an intensive care unit (ICU) who need safe diagnostic and therapeutic interventions. The devices used in ICU should ensure accuracy, reliability and safety of alarms. The goal of personalized medicine in the ICU is to predict which diagnostic tests, monitoring interventions and treatments are necessary. In this study, we propose an intelligent approach based on artificial neural networks which is able to automatically learn the features of a patient and consequently send the required alarms in order to reduce the number of wrong alarms in ICU. Six of the most important risk factors are used and the importance of input variables is quantified by weighting according to expert's knowledge. The data chosen for this study have been provided in a real ICU environment in the University of Queensland in Australia. The results demonstrate that the proposed neural approach can be used as an efficient method for controlling vital signs in a real ICU environment. [ABSTRACT FROM AUTHOR]

The past few years have shown an increase in the amount of data that are being generated in all fields. This increase is due to human needs to all aspects from business to science. One of these fields is medicine with uncertain data. For these amount of data there exists computational methods and tools for analysis and it requires medical informatics researchers and specialists to choose the most appropriate method to cope with these data. This paper presents one of the common data mining tasks, association rule mining, when considering particular continuous time series measurements. The most important goal of this study is dealing with and processing time series data for the purpose of extracting linguistic rules. Also, comparing the results of this method with the results of classical statistical analysis is the second objective. A three-part analytical pipeline is used in this study as a new mining approach, consisting of data preparation, data transformation, and data analysis to elicit knowledge about the interaction of the parameters measured and the effect of different drugs on the rats. Weka data mining toolkit has been employed for extracting knowledge in the form of association rules and the important rules identified by this toolkit are interpreted for their medical significance. Discretizing time series data and linguistic representation of rules have been demonstrated. This study exhibits this new approach by analysis of the data of the cardiovascular responses to specific medications in rats that have been recorded by lab chart software in the laboratory. Once the time series was discretized, simple association rule mining methods are used to extract rules. The association rules that are discovered can provide the domain expert with new knowledge about the possible effects of injected rats or to help to improve annotation consistency1. [ABSTRACT FROM AUTHOR]

ABSTRACT A new operational amplifier is presented based on the conventional telescopic amplifier structure. A novel method is used to increase the DC gain of the telescopic amplifier. This method does not degrade the output swing, bandwidth, settling time and the phase margin of the telescopic amplifier. Proposed structure has been simulated by HSPICE software using level 49 parameters (BSIM3v3) in a typical 0.18 µm Complementary metal-oxide-semiconductor (CMOS) technology. HSPICE simulation confirms the theoretical estimated improvements. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The current study examined the plain fatigue and the fretting fatigue behaviors of the piston pin alloy (16MnCr5 steel) under fully-reversed rotating bending loading. The standard fatigue testing sample was cut out from the piston pin used in internal combustion engines. Furthermore, the failure mechanisms of samples were studied using field emission scanning electron microscopy. The obtained result indicated that the fatigue lifetime of 16MnCr5 steel was significantly affected by the fretting damage. The investigation of the failure mechanisms determined that the fracture behavior of the specimens under the plain fatigue and fretting fatigue conditions was brittle; however, it was considerably influenced by the casting defects in the samples. The test results can merely be used to compare the fatigue performance of the studied material under different conditions. More naturalistic experiments are required for further optimization in designing components made from this material to improve their reliability and service life, especially in contacting surfaces under rotating bending conditions. [Display omitted] • Plain and fretting fatigue behaviors of 16MnCr5 steel were investigated cyclic bending conditions. • The decrease in fatigue lifetimes was about 89–93%, when the fretting damage was considered during fatigue testing. • The fracture behavior was brittle due to the presence of cleavage facets on the fracture surfaces. [ABSTRACT FROM AUTHOR]

Background and purpose: Neuropathic pain is one of the most common types of chronic pain that is very difficult to treat. Numerous studies have shown the potential role of vitamins in relieving both hyperalgesia and allodynia. Based on the convincing evidence, this study was designed to evaluate the possible antinociceptive effect of biotin on neuropathic pain in rats. Experimental approach: This study was performed on male Sprague Dawley rats weighing 200-300 g. Neuropathic pain was induced by tying the sciatic nerve. Chronic constriction injury (CCI) of the sciatic nerve resulted in hyperalgesia and allodynia. To measure the thermal hyperalgesia, the plantar test was used. Also to evaluate the cold and mechanical allodynia, acetone test and von Frey test were applied. Biotin (4, 8, and 16 mg/kg) was administered orally as two different treatment regimens, acute and chronic. Findings/Results: Acute oral administration of biotin (4, 8, and 16 mg/kg p.o.) on the 7th, 14th, and 21st postoperative days couldn't reduce pain sensitivity compared to the CCI group. However, following the oral administration of biotin (8 and 16 mg/kg p.o.) from the first day after the surgery until day 21, mechanical allodynia (P < 0.001) and heat hyperalgesia (P < 0.05) significantly relieved. Conclusion and implications: Our results suggest that biotin can be considered as a potential therapeutic for the treatment of neuropathic pain, and supplementation with this vitamin could reduce the required doses of analgesic drugs. However, further studies are needed to confirm this hypothesis. [ABSTRACT FROM AUTHOR]

Background: Staphylococcus aureus is one of the most important bacteria causes nosocomial infections, which by the biofilm formation can be effective in the creation of chronic diseases, and the creation and strengthening of drug resistance. The present study aimed to evaluate the genotypic and phenotypic biofilm formation by S. aureus isolated from clinical samples and their association with antimicrobial resistance. Materials & Methods: In this descriptive cross-sectional study from Dec 2019 to Sep 2019, 200 clinical samples were obtained from AJA hospitals in Tehran. All samples were analyzed using blood agar, Baird-Parker Agar, mannitol salt agar and catalase, OF and coagulase assays. Antimicrobial resistance pattern of isolates was determined by the disc diffusion method. Multiplex PCR method was used to identify biofilm formation genes, includes icaA, icaB, icaC, and icaD genes. Data analyzed using SPSS 20 and the X2 test. Results: Out of 200 cultivated samples, 83 (41.5%) cases were confirmed as S. aureus. The highest resistance was observed to Penicillin (94%), Tetracycline (72%), Ampicillin (54%), and Cefoxitin (51%), respectively. Phenotypic biofilm formation ability reported in 65% of isolates. The frequency of presence of icaA, icaB, icaC, and icaD genes was estimated at 67.4%, 60.2%, 61.4%, and 62.6%, respectively. Eighty-seven percent of biofilm producing strains were multidrug-resistant, while all the biofilm negative strains were non- multiple drug resistance (P< 0/05). Conclusion: According to the results, Biofilm-positive strains have a very high propensity to demonstrate antimicrobial resistance, multidrug resistance and resistance to methicillin. [ABSTRACT FROM AUTHOR]

The small-strain shear modulus Gmax is a key material parameter in modeling the behavior of soils subjected to dynamic loading. Recent experimental results indicate that seasonal weather interaction with near-surface soils causes Gmax to change by up to an order of magnitude in some climates, with a hysteretic response upon drying and wetting. The increase in Gmax during drying and the stiffer response during subsequent wetting have been postulated to be due to plastic hardening during drying. To further understand this behavior, a series of isotropic compression tests were performed on compacted silt specimens at different values of matric suction to evaluate changes in the preconsolidation stress with suction. The Gmax values obtained previously on this silt matched well with a model using a hardening parameter independently derived from the isotropic compression tests, as well as the parameters of the soil water retention curve (SWRC). The model showed an increase in Gmax during drying from an initially saturated condition that was directly related to the increase in preconsolidation stress with suction, and the trends in Gmax followed transitions in the shape of the SWRC. The hardening parameter from these tests was also suitable for modeling the greater values of Gmax encountered during rewetting of the soil. The role of the preconsolidation stress in the model confirmed that changes in Gmax correspond to elastoplastic hardening mechanisms during drying rather than solely to changes in matric suction. [ABSTRACT FROM AUTHOR]

A novel and highly efficient ruthenium-based catalyst was synthesized by immobilizing Ru(CO) onto functionalized multi-walled carbon nanotubes. The catalyst was characterized by Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, transmission electron microscopy, energy dispersive X-ray analysis, diffuse reflectance UV-Vis spectrophotometry, inductively coupled plasma and elemental analysis. This heterogeneous catalyst was successfully applied in the multi-component synthesis of various xanthene derivatives in good to excellent yields (28 samples, up to 96 % yield) under reflux condition and ultrasonic irradiation. The prepared catalyst was recovered four times without appreciable loss of activity. [ABSTRACT FROM AUTHOR]

The synthesis and characterization of a highly efficient and reusable catalyst, ruthenium immobilized in zeolite beta, are reported. The catalyst was characterized by powder X-ray diffraction, BET surface area measurements, scanning electron micrographs, Fourier-transform infrared spectroscopy, inductive coupled plasma, and elemental analysis. The supported material was used as an efficient catalyst for the one-pot three-component synthesis of 4 H-benzo[ b]pyrans and pyrano[ c]chromenes in good yields. The catalyst was separated from the reaction mixture and reused up to five runs without significant loss of activity. [ABSTRACT FROM AUTHOR]

Three-component cyclocondensation of β-naphthol, aldehydes, and 5,5-dimethylcyclohexane-1,3-dione (dimedone) was catalyzed efficiently by ruthenium chloride hydrate under mild reaction conditions to afford 12-aryl or alkyl-8,9,10,12-tetrahydrobenzo[ a]xanthen-11-one derivatives in good to excellent yields. [ABSTRACT FROM AUTHOR]

[image omitted] Synthesis of dibenzoxanthenes through condensation of β-naphthol with various aromatic and aliphatic aldehydes in ethanol as an ecofriendly solvent using RuIII as catalyst is reported. [ABSTRACT FROM AUTHOR]

Background: The most common gender-specific malignancies are cancers of the breast and the prostate. In developing countries, cancer screening of all at risk is impractical because of healthcare resource limitations. Thus, determining high-risk areas might be an important first screening step. This study explores incidence patterns of potential high-risk clusters of breast and prostate cancers in southern Iran.Methods: This cross-sectional study was conducted in the province of Kerman, South Iran. Patient data were aggregated at the county and district levels calculating the incidence rate per 100,000 people both for cancers of the breast and the prostate. We used the natural-break classification with five classes to produce descriptive maps. A spatial clustering analysis (Anselin Local Moran's I) was used to identify potential clusters and outliers in the pattern of these cancers from 2014 to 2017.Results: There were 1350 breast cancer patients (including, 42 male cases) and 478 prostate cancer patients in the province of Kerman, Iran during the study period. After 45 years of age, the number of men with diagnosed prostate cancer increased similarly to that of breast cancer for women after 25 years of age. The age-standardised incidence rate of breast cancer for women showed an increase from 29.93 to 32.27 cases per 100,000 people and that of prostate cancer from 13.93 to 15.47 cases per 100,000 during 2014-2017. Cluster analysis at the county level identified high-high clusters of breast cancer in the north-western part of the province for all years studied, but the analysis at the district level showed high-high clusters for only two of the years. With regard to prostate cancer, cluster analysis at the county and district levels identified high-high clusters in this area of the province for two of the study years.Conclusions: North-western Kerman had a significantly higher incidence rate of both breast and prostate cancer than the average, which should help in designing tailored screening and surveillance systems. Furthermore, this study generates new hypotheses regarding the potential relationship between increased incidence of cancers in certain geographical areas and environmental risk factors. [ABSTRACT FROM AUTHOR]

The catalyst is recyclable and reusable at least 4 times. [ABSTRACT FROM AUTHOR]