A study on the ethical components of nursing practice (moral distress, ethical sensitivity, ethical decision)

This paper is an applied research in terms of objective and a descriptive research in terms of method. Having prepared the research plan, a questionnaire was designed based on goals and hypotheses of the research and was sent to the statistical universe. Also this paper is a field research in terms of data collection. As regards theoretical bases of the research, library data collection method has been applied. So, the required data has been gathered by referring to the related references, books, libraries and so on. To design a questionnaire and gather the opinions of the statistical universe members, field study method and researcher-made questionnaire have been used. The statistical universe comprises nurses and head of ICU and head nurses of Najmieh Hospital in Tehran. The respondents were selected by random sampling method. Also to estimate sample size, Morgan table was applied. The statistical universe consists of 65 members and according to the table, 56 questionnaires were determined for the research. So 60 questionnaires were sent and 58 ones were returned. Face and content validity of the research tool were approved by experts. The test reliability was estimated 0.777 by calculating Cronbach's alpha coefficient. In this paper, factor analysis based on partial least squares structural equations method has been applied to analyze more important factors and coefficients, estimate independent variables coefficients and even determine effectiveness of each independent variable on each other and determine appropriateness of the questions and their coefficients in explaining the related index. The main result of this paper presents a proper model for the relation of effective variables on nurse performance by using regression model. © IDOSI Publications, 2014

A fingerprint based metric for measuring similarities of crystalline structures

Measuring similarities/dissimilarities between atomic structures is important for the exploration of potential energy landscapes. However, the cell vectors together with the coordinates of the atoms, which are generally used to describe periodic systems, are quantities not suitable as fingerprints to distinguish structures. Based on a characterization of the local environment of all atoms in a cell we introduce crystal fingerprints that can be calculated easily and allow to define configurational distances between crystalline structures that satisfy the mathematical properties of a metric. This distance between two configurations is a measure of their similarity/dissimilarity and it allows in particular to distinguish structures. The new method is an useful tool within various energy landscape exploration schemes, such as minima hopping, random search, swarm intelligence algorithms and high-throughput screenings

Inhibition of fatty acids profile changes of cobia (Rachycentron canadum) fillets during frozen storage by packaging under vacuum system

This study was aimed to investigate the effect of vacuum packing (VP) on the fatty acids profiles in cobia (Rachycentron canadum) fillets during an extended frozen storage period. Cobia fillets were treated under vacuum system then stored at -18°C for up to 6 months and compared to control conditions. As a result of a frozen storage period of 6 months, a marked content decrease was found in the fatty acid groups such as MUFA, PUFA and ω-3 PUFA, as well as in the ω-3/ ω-6 ratio. However, a preserving effect on such fatty acid parameters could be observed due to the VP treatment. Assessment of the polyene index (PI) indicated an increased lipid oxidation development as a result of the frozen storage time; however, this increase was partially inhibited by the vacuum packaging. Results indicate that vacuum packaging was a proper way to reduce lipid oxidation in Cobia fillets and extend their shelf life by omitting available oxygen. Thus the employment of VP alone or in combination with other protective strategies is recommended

Niche inheritance: a cooperative pathway to enhance cancer cell fitness though ecosystem engineering

Cancer cells can be described as an invasive species that is able to establish itself in a new environment. The concept of niche construction can be utilized to describe the process by which cancer cells terraform their environment, thereby engineering an ecosystem that promotes the genetic fitness of the species. Ecological dispersion theory can then be utilized to describe and model the steps and barriers involved in a successful diaspora as the cancer cells leave the original host organ and migrate to new host organs to successfully establish a new metastatic community. These ecological concepts can be further utilized to define new diagnostic and therapeutic areas for lethal cancers.Comment: 8 pages, 1 Table, 4 Figure

Success Rate and Complications of Internal Jugular Vein Catheterization With and Without Ultrasonography Guide

Background: Central venous catheterization (CVC) is an important procedure in emergency departments (EDs). Despite existence of ultrasonography (US) devices in every ED, CVC is done using anatomical landmarks in many EDs in Iran. Objectives: This study aimed to compare the traditional landmark method vs. US-guided method of CVC placement in terms of complications and success rate. Patients and Methods: In this randomized controlled trial, patients who were candidate for internal jugular vein catheterization, and referred to Baqiyatallah Hospital ED were randomly allocated into US-guided CVC and anatomical landmarks guided CVC groups. Central vein access time, number of attempts, success rate, and complications in each group were evaluated. Mann-Whitney U, chi-square and Fisher exact tests along with Pearson and Spearman correlation coefficients were used to analyze the data. Results: Out of 100 patients, 56 were male and 44 were female. No significant differences were found between the US-guided and traditional landmark methods of CVC insertion in terms of age, gender, BMI, and site of catheter insertion. The mean access time was significantly lower in the US-guided group (37.12 ± 17.33 s vs. 63.42 ± 35.19 s, P < 0.001). The mean number of attempts was also significantly lower in the US-guided group (1.12 ± 0.3 vs. 1.58 ± 0.64 times, P < 0.001). Eighty-eight percent of patients in the US-guided group were catheterized in the first attempt, while 50% of patients in the traditional landmark group were catheterized in the second or more attempts (P < 0.001). The success rate was 100% in the US-guided group, while it was 88% in the landmark group (P = 0.013). Moreover, the rate of complications was significantly lower in the US-guided group (4% vs. 24%, P = 0.004). Conclusions: The US-guided method for CVC placement was superior to the traditional landmark method in terms of access time, number of attempts, success rate, and fewer complications

An advanced numerical model of friction stir welding of DH36 steel

A numerical model of Friction Stir Welding (FSW) of DH36 steel plate (6mm thickness) has been developed using a CFD technique. Two welding speed conditions were used, a low welding speed of 200 RPM - 100mm/min, and a high welding speed of 550RPM- 400 mm/min. The heat generation, material flow and strain rate were calculated based on plastic deformation and frictional contact between the tool and workpiece. A CFD-based model has been produced to represent the asymmetry in temperature distribution between the advancing and retreating side, the material flow and the strain rate. The geometry of the model includes the tool plunged into the plate. The cooling system was also included in the simulation by calculating the heat flux lost for each part of the tool. The heat generated by viscous dissipation away from the tool was also taken into account. The total heat generated was divided into the individual tool parts (shoulder, probe side and probe end) and was found to be in good agreement with the experimental results for the areas affected by these parts. The maximum temperature obtained for the slow welding speed was 1012oC and for the high welding speed was 1250oC. Experimental metallographic examination has also been carried out on DH36 FSW steel plates to validate the CFD model. SEM analysis showed the formation of a fine microstructure of bainite, acicular ferrite and ferrite/cementite aggregate in the welded zone as compared to the ferrite/pearlite morphology in the base metal. It is found from the CFD and experimental results that the high speed welding conditions can produce defects such as wormholes and cracks in the welds associated with the probe side and probe end due to the lack of material flow especially on the advancing side. Tensile and fatigue testing were carried out for both slow and high welding speed samples, which broke outside the welded region in the tensile test, however, slow welding speed samples show more resistance to fatigue test and survived 644128 cycles, the high speed welding samples failed after 111,736 cycles under the same load

Effect of Phosphorus and Strontium Additions on Formation Temperature and Nucleation Density of Primary Silicon in Al-19 Wt Pct Si Alloy and Their Effect on Eutectic Temperature

The influence of P and Sr additions on the formation temperature and nucleation density of primary silicon in Al-19 wt pct Si alloy has been determined, for small volumes of melt solidified at cooling rates _T of ~0.3 and 1 K/s. The proportion of ingot featuring primary silicon decreased progressively with increased Sr addition, which also markedly reduced the temperature for first formation of primary silicon and the number of primary silicon particles per unit volume �Nv: When combined with previously published results, the effects of amount of P addition and cooling rate on �Nv are in reasonable accord with �Nv� _T ¼ ðp=6fÞ1=2 109 [250 � 215 (wt pct P)0.17]�3, where �Nv is in mm�3, _T is in K/s, and f is volume fraction of primary silicon. Increased P addition reduces the eutectic temperature, while increased Sr appears to generate a minimum in eutectic temperature at about 100 ppmw Sr

Regional vulnerability of the hippocampus to repeated motor activity deprivation

Spontaneous vertical and horizontal exploratory movements are integral components of rodent behavior. Little is known, however, about the structural and functional consequences of restricted spontaneous exploration. Here, we report two experiments to probe whether restriction in vertical activity (rearing) in rats could induce neuro-hormonal and behavioral disturbances. Rearing movements in rats were deprived for 3 h/day for 30 consecutive days by placing the animal into a circular tunnel task. Rats temporarily deprived of rearing behavior showed elevated plasma corticosterone levels but no detectable psychological distress and/or anxiety-related behavior within an elevated plus maze. However, rats emitted a greater number of 22-kHz ultrasonic vocalizations and spent significantly more time vocalizing than controls when deprived of their rearing behavior. Despite intact spatial performance within wet- and dry-land spatial tasks, rearing-deprived rats also exhibited a significant alteration in search strategies within both spatial tasks along with reduced volume and neuron number in the hippocampal subregion CA2. These data suggest a new approach to test the importance of free exploratory behavior in endocrine and structural manifestations. The results support a central role of the CA2 in spontaneous exploratory behavior and vulnerability to psychological stress. © 2015 Elsevier B.V

Modelling of friction stir welding of 304 stainless steel

A 3-D Eulerian steady-state CFD model has been developed to simulate the Friction Stir Welding (FSW) of 6mm plate 304 stainless steel (304SS). The Polycrystalline BoroNitride- Tungsten Rhenium (PCBN-WRe) hybrid tool was modelled with the workpiece in a fully sticking condition. The viscosity of stainless steel was calculated from the flow stress equation taken from a previous study of hot working carried out in a range of temperatures between 800oC-1200 oC and strain rates 0.001 s-1 to 5 s-1. The model predicted the temperature distribution in the Stirred Zone (SZ) for three welding cases including low, intermediate and high rotational speed/traverse speeds. The model also predicts that localised melting may occur if the tool rotational speed exceeds 400RPM. Finally, the model suggested a larger probe (12mm diameter at the shoulder base and 5.8mm length) with a stationary shoulder would prevent the localised melting and allow an increase in welding speeds without the associated introduction of stagnant zone related weld defects