Serviceability Assessment of Continuous Beams Strengthened by SMA Strands under Cyclic Loading

Since the wide cracks or large deflections can have a significant effect on the appearance of concrete elements and may cause some uncommon behavior, therefore, serviceability of concrete structures requires investigation. The main objective of this paper is to study experimentally the serviceability of continuous reinforced concrete (RC) beams strengthened by Ni-Ti strands. In addition, some building code provisions were used to calculate crack width and deflection. The current study presents the experimental results to verify the accuracy of building codes’ provisions for continuous RC beams strengthened by SMA strands. Although a pattern of smaller width cracks was monitored for strengthened beams, more than 50% of the crack widths were recovered because of super elastic SMA strands. The performance of crack width provisions illustrates an overestimated crack width for SMA RC beams. Moreover, the predicted values for immediate deflections based on building codes provided a good agreement, although the effective reinforcement ratio (steel reinforcement and SMA strands) had a significant effect on immediate deflections of reinforced concrete beams strengthened by SMA strands under service loads

New Architectures for Low Complexity Scalable Phased Arrays

Inspired by the unique advantages of phased arrays in communication and radar systems, i.e. their capability to increase the channel capacity, signal-to-noise ratio, directivity, and radar resolution, this dissertation presents novel architectures for low-complexity scalable phased arrays to facilitate their widespread use in commercial applications. In phased arrays, phase shifters are one of the key components responsible for adjusting the signal phase across the array elements. In general, phase shifters and their control circuitry play a significant role in determining the complexity and size of conventional phased arrays. To reduce phased arrays’ complexity and size without degrading their performance, two new circuit architectures for scalable phased arrays with a significantly reduced number of phase shifters and control signals are presented. These architectures can be utilized for designing phased arrays in receive as well as transmit mode. The phased arrays designed based on the proposed architectures are intended for applications such as 5G communications and automotive radars for advanced driver assistance systems (ADAS) and autonomous vehicles.PHDElectrical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/147494/1/noyan_1.pd

A Preliminary Study of Perception and Coping Mechanism of Breast Cancer Patients in an Iranian City

The life expectancy of women in Iran has increased in the last quarter of the 20th century. On the other hand obesity has increased during the first decade of the 21th century for both adult males and females but particularly for females. These trends are contemporary with a growing incidence of breast cancer among women in urban areas. Casual observation has shown that organized and systematic coping support and mechanism for women with breast cancer disease has expanded much less than the treatment technology, leaving surviving women in ambiguity and fear of unknown. The analysis of qualitative data from a preliminary study of women in one city confirms the limited support for coping with the disease and the aftermath of the technology based treatments. Except for a few educated women, the majority of the subject studied in this research saw their situation as catastrophic and ambiguous. They relied on their religious belief and family support to cope with their situation, but had limited success due to their lack of knowledge about the natural order of the disease and consequences of treatment. While there is need for more comprehensive studies of coping strategies using representative sample of breast cancer patients across rural and urban areas of Iran, the findings from the present study calls for organized and systematic community based support system to help women faced with this disease, to cope

Trends of particulate matter (PM10) concentration and related Air Quality Index (AQI) during 2005-2012 in Kermanshah, Iran

Background and Aims: Atmospheric dust, also known as a part of PM10, can cause some adverse effects on public health. The aim of this study was to investigate dust concentration trends in Kermanshah city and also to compare related Air Quality Index (AQI) in different years, seasons and months during 2005 to 2012.Materials and Methods: In this descriptive-analytical study, totally 2589 samples were taken from air monitoring stations owned by the Environmental Protection Agency. The ghatered data were then analyzed using SPSS software V.16.Results: The frequency percentage of PM10 concentrations based on AQI descriptions (healthy, moderate, unhealthy for sensitive groups, unhealthy, very unhealthy and dangerous) were 12.16, 68.36, 12.82, 3.43, 0.77 and 2.43 percents, respectively. It is further interesting to note that in all monitored days during the present study, 19.43% of total days were in unhealthy conditions within AQI> 100. So that, although the frequency of dusty days decreased from summer to fall, failure to meet air quality standard requirements increased from fall to winter and further to spring.Conclusion: The results of this study showed that the observed changes in PM10 concentration were significant in the course of seasons and months. The worst air quality condition occured in summer (specially July). It seems possible that these results are due to frequent dust enterance originating from neighboring countries, humidity reduction, drought and unsustainable use of water resources, temperature rising, as well as wind speed and direction. Because of adverse health effects of particulate matter, it is necessary to promote environmentally aware and responsible science of its trend, short-term and long-term and also international planning to reduce its detrimental impacts.Key words: Air pollution, AQI, Dust, Kermansha

A Study on the Effectiveness of Learning Strategies in English

This article is concerned with ''learning strategies of English in English Foreign Language setting in Iran. The role of language strategy is to reach or complete a language learning process or language teaching process in target language. It is worth mentioning strategies of learning can be considered as the important factor in learning and teaching target language in order to help determine how language learners learn their target language in EFL or ESL settings. Subjects for this research project were eighty EFL students in the age range of 18 to 24 at under-graduate level in Bushehr Persian Gulf University. The two types of questionnaires were designed to reach the purpose of this study: the first test included age, gender, language attitude and subjects etc. and a learning strategies questionnaire has included a twenty-nine-test adapted from the original willing (1994) survey. However, the Effectiveness of Learning Strategies was revealed in this study

DNA Binding and Antitumor Activity of α-Diimineplatinum(II) and Palladium(II) Dithiocarbamate Complexes

The two water-soluble designed platinum(II) complex, [Pt(Oct-dtc)(bpy)]NO3 (Oct-dtc = Octyldithiocarbamate and bpy = 2,2′ -bipyridine) and palladium(II) complex, [Pd(Oct-dtc)(bpy)]NO3, have been synthesized and characterized by elemental analyses, molar conductivity measurements, IR, 1H NMR, and electronic spectra studies. Studies of antitumor activity of these complexes against human cell tumor lines (K562) have been carried out. They show Ic50 values lower than that of cisplatin. The complexes have been investigated for their interaction with calf thymus DNA (CT-DNA) by utilizing the electronic absorption spectroscopy, fluorescence spectra, and ethidium bromide displacement and gel filtration techniques. Both of these water-soluble complexes bound cooperatively and intercalatively to the CT-DNA at very low concentrations. Several binding and thermodynamic parameters are also described

Relationship Between Upper Airway Ultrasound Parameters and Degree of Difficult Laryngoscopy for Endotracheal Intubation

Background Limited research has been conducted on the role of ultrasound in predicting difficult laryngoscopy (DL). This study aimed to evaluate the predictive values of upper airway ultrasound parameters for the degree of DL during intubation. Methods and Materials This observational-prospective study was performed on 120 patients requiring intubation during elective surgery. Initially, the degree of DL was assessed by the Mallampati Scale. The patients' neck circumference was then measured and recorded.  Ultrasound was used to determine the Hyomental distance in the neutral position (HMDN) and in the head extension (HMDE), as well as tongue width (TW), tongue thickness (TT), oral cavity height ratio (OCH), the amount of soft tissue (ST), and the Tongue thickness-to-oral cavity height ratio (TT/OCH) was used. Afterward, the patients underwent general anesthesia and were intubated. The degree of difficult intubation was measured based on the Cormack-Lehane classification system, according to which the patients were divided into easy and difficult laryngoscopy groups. Finally, the effectiveness of the two methods of ultrasound and intubation was compared. Results The Cormack score and Mallampati class recorded intubation difficulty as 28.3% and 30.8%, respectively. According to the Cormack score, only the neck circumference was significantly associated with intubation difficulty (P = 0.002). In terms of Mallampati class, the neck circumference and HMDN, HMDE, TT, OCH, and ST were significantly associated with the degree of DL (P <0.05). The predictive value of ultrasound parameters for the degree of DL was low based on both of the criteria (AUC <0.7). Conclusion The results showed that although Mallampati class lacked the desirable accuracy, it provided a better predictive measure for the degree of DL during intubation compared to the Cormack score

The Study of the Protective Effect of Vitamin E and Retinoic Acid on Testicular Tissue in Mice Treated with Cyclophosphamide

Background and Aim: One of the side effects of anticancer drugs is spermatogenesis disorder. Hence, the evaluation of sperm production after chemotherapy has been the subject of several studies today. Methods: Adult male albino mice weighing 20±2 g were randomly divided into 5 groups (n = 4);control, cyclophosphamide (12 mg/kg/day), cyclophosphamide and vitamin E (200 mg/kg/day), cyclophosphamide and retinoic acid (500 µL/72h), cyclophosphamide and retinoic acid (250 µL/72h) and vitamin E (100 mg/day). The treatment was continued for 35 days and at the end of the rats was anesthetized and testicular tissue was isolated, weighed, fixed, and stained with hematoxylin-eosin. Results: A significant decrease (p-value ≤ 0.0001) in the mean diameter of seminal vesicles, epithelial thickness, and index of tubular differentiation was observed in the testis tissue of mice treated with cyclophosphamide compared to the control group. In cyclophosphamide recipients with retinoic acid or vitamin E, parameters significantly increased to the level of the control group (p-value ≤ 0.0001), whereas cyclophosphamide co-administration with retinoic acid and vitamin A had a less tissue-protective effect. Conclusion: Vitamin E and retinoic acid can offset the adverse effects of cyclophosphamide on spermatogenesis and may be inducers of spermatogenesis, while the combination of these two antioxidants has fewer efficacies. *Corresponding Author: Fatemeh Sadat Moravej; Email: [email protected] Please cite this article as: Karimi A, Behmard V, Toghiani S, Moravej FS. The Study of the Protective Effect of Vitamin E and Retinoic Acid on Testicular Tissue in Mice Treated with Cyclophosphamide. Arch Med Lab Sci. 2020;6:1-8 (e9). https://doi.org/10.22037/amls.v6.3152

Characterisation of Spreadability Behaviour of Ti6Al4V Powders for Additive Manufacturing

Powder-bed based Additive Manufacturing (AM), also known as 3D printing, is an emerging technology to produce high quality end-parts at a cost and time effective manner as compared to the traditional subtractive manufacturing processes. The study of metal powder-bed processes usually involves two critical steps which includes the spreading of the powder and the fusion of the layers. Spreadability of powders is an essential characteristic in determining the total build time and quality of the final product. The spreadability is thought to be linked to the powder characteristics, mostly the flow behaviour, which is influenced by the individual particle properties and environmental conditions. This thesis endeavours to investigate the spreading behaviour of two samples of titanium alloy (Ti6Al4V) powders, produced by Gas Atomisation (GA) and Hydrogenation-dehydrogenation (HDH) methods. The spreading behaviour of each sample has been investigated using an in-house spreading rig set up at University of Leeds, with a set of parameters, including the gap size between the blade and build plate (ranging between 191 µm to 508 µm) and spreading velocity (ranging between 50mm/s to 200mm/s) as the variables, while the mass of the fed powder as a constant. The bulk layer density and mass per area are the two measures of spreadability introduced in this study. It is found that the quality of the spread layer is significantly influenced not only by the powder properties, but also the process parameters. GA powder exhibited spherical shapes, which in turn created homogeneous layers due to improved packing behaviour compared to HDH powder which were characterised by irregular shapes impeding powder flow. Additionally, the bulk layer density of GA powder decreased when the spreading velocity was increased, but this correlation was not established for HDH powder. This owes to the fact that HDH powders are of irregular morphologies, hence they consist of particular particle arrangements under the spreader at certain velocities. An increase in the spreading velocity also resulted in a gradual reduction in the values of the mass per area, suggesting that higher velocities jeopardise the quality of the spread layer. Due to the limitations of spreader rig, only a specific amount of powder to cover the build plate was utilised, however, in reality an infinite amount of powder is fed for spreading the layers. It is concluded that GA powders outperform HDH powders in terms of reliability and creating higher bulk layer densities, which is essential in ensuring quality layers and, consequently, defect-free end parts. The quality of the layer is determined by calculating the average bulk layer density. In AM, a higher bulk layer density is desirable as it demonstrates better packing quality , homogenous layers of low porosity, which consequently results into end parts of high density and increased mechanical strength

CT-measured pulmonary artery diameter as an independent predictor of pulmonary hypertension in cystic fibrosis

Purpose: The role of computed tomography (CT) scan, as a promising prognostic imaging modality in cystic fibrosis(CF), has been widely investigated, focusing on parenchymal abnormalities. The aim of the present study was to evaluate the diagnostic performance of thoracic vascular parameters on CT to detect pulmonary hypertension (PH). Material and methods: CF patients who contemporaneously underwent CT and echocardiography were retrospectively enrolled. Baseline characteristics in addition to pulmonary artery diameter (PAD) and pulmonary to aortic (PA/A) ratio were compared between cohorts with and without PH, based on the results of echocardiography separately in paediatric patients (< 18) and adults (≥ 18). Results: Of a total 119 CF patients, 39 (32.8%) had PH (paediatric: 23/78, 29.5%, adult: 16/41, 39%). In paediatric CF patients, mean age, HCo3, PCo2, and pulmonary artery diameter (PAD) were significantly higher in the PH group compared to the non-PH group. Mean pulmo however, only PAD remained as the independent predictor of PH based on multivariate analysis (overall: 22.86 mm [±3.86] vs. 18.43 mm [±4.72], p = 0.005, paediatric patients: 22.63 mm [±4.4] vs. 17.10 mm [±4.64], p = 0.03). Using a cut off of 19.25 mm, the diagnostic performance of PAD to detect PH was found to be as follows: sensitivity = 82%, specificity = 70%, and accuracy = 73.1%. No significant difference was demonstrated in PAD between PH and non-PH groups in adults with CF (23.19 [±3.60] vs. 21.34 [±3.49], p = 0.7). Conclusions: In CF patients, PAD revealed an age-dependent performance to detect PH. PAD can be applied to predict pulmonary hypertension in paediatric CF patients and may be recommended to be routinely measured on follow-up chest CT scan in childhood CF