Risk-Based Model for Effective Marshalling of Dangerous Goods Railway Cars

Today, railroad companies transport many varieties of dangerous goods (DG). Train derailments, especially those involving DG, can be catastrophic in terms of loss of life and environmental damage. In North America, the transportation of DG is governed by regulations published by the Canadian and United State's governments. While the regulation is important in terms of providing overall guidelines, they do not address the problem of optimally positioning DG cars in terms of their potential for derailment and the associated risks. Currently, most rail yard operations do not consider the potential effect of the position of DG cars on the risk of derailment. This research is concerned with the problem of how to place DG cars in a train in the train assembly process so that the overall derailment risk can be minimized. The approach considers both the probability of railway cars derailing en route by position as well as the time associated with additional operations in the rail yard. This work has resulted in a useful decision support tool for assisting rail yard operation managers to achieve an optimum trade-off between derailment risk and operating costs in assembling trains. The merits of this new car placement model are illustrated through a case study of a real railway corridor that connects Barstow Yard in California to Corwith Yard in Chicago over 2100 miles and involves a range of track features. The case study demonstrates that the proposed risk minimization strategy could be implemented with minimal rail yard operation cost

Hotspot Location Identification Using Accident Data, Traffic and Geometric Characteristics

Determining the criterion for critical limits is always one of the essential challenges for traffic safety authorities. The purpose of identifying accident hotspots is to achieve high-priority locations in order to effectively allocate the safety budgets as well as to promote more efficient and faster safety at the road network level. In recent years, human, vehicle, road and environment have been recognized as the three main effective elements of the road transportation in the occurrence of accidents. In the present study, with combining the parameters related to accidents, geometric parameters of the accident location and traffic parameters, hotspots were identified by using the superior methods of Poisson regression and negative binomial distribution and based on the combined criteria of frequency and severity of accidents and equivalent damage factors. Then using Time Series Models in ANN, result were compared and validated. The results of ANN models demonstrate that the frequency method of accidents tends toward places with high traffic volume. MATLAB and STATA software were used. Non-native plumbing, curvature, slope, section length and residential area had more significance, and their coefficients indicated the significant effect of these parameters on the occurrence of the frequency and severity of accidents in hotspot locations

Turbulent flows over porous lattices: alteration of near-wall turbulence and pore-flow amplitude modulation

Turbulent flows over porous lattices consisting of rectangular cuboid pores are investigated using scale-resolving direct numerical simulations. Beyond a certain threshold which is primarily determined by the wall-normal Darcy permeability, ${K_y}^+$, near-wall turbulence transitions from its canonical regime, marked by the presence of streak-like structures, to another marked by the presence of spanwise coherent structures reminiscent of the Kelvin-Helmholtz (K-H) type of instability. This permeability threshold agrees well with that previously established in studies where permeable-wall boundary conditions had been used as surrogates for a porous substrate. None of the substrates investigated demonstrate any drag reduction relative to smooth-wall turbulent flow. At the permeable surface, a significant component of the flow is that which adheres to the pore geometry and undergoes amplitude modulation (AM). This pore-coherent flow remains notable within the substrates, highlighting the importance of the porous substrate's microstructure when the overlying flow is turbulent, an aspect which cannot be accounted for when using continuum-based approaches to model porous media flows or effective representations such as wall boundary conditions. The severity of the AM is enhanced in the K-H-like regime, which has implications when designing porous substrates for transport processes. This suggests that the surface of the substrate can have a geometry which is different than the rest of it and tailored to influence the overlying flow in a particular way

Cryptanalysis of two recently proposed PUF based authentication protocols for IoT: PHEMAP and Salted PHEMAP

Internet of Things(IoT) consists of a large number of interconnected coexist heterogeneous entities, including Radio-frequency identification(RFIDs) based devices and other sensors to detect and transfer various information such as temperature, personal health data, brightness, etc. Security, in particular, authentication, is one of the most important parts of information security infrastructure in  IoT systems. Given that an IoT system has many resource-constrained devices, a goal could be designing a proper authentication protocol that is lightweight and can resist against various common attacks, targeting such devices. Recently, using Physical Unclonable Functions (PUF) to design lightweight authentication protocols has received a lot of attention among researchers. In this paper, we analyze two recently proposed authentication protocols based on PUF chains called PHEMAP and Salted PHEMAP. We show that these protocols are vulnerable to impersonate, desynchronization and traceability attacks

Hypoglycemic Effect of Aqueous Shallot and Garlic Extracts in Rats with Fructose-Induced Insulin Resistance

The present study has been carried out to investigate the effect of aqueous extract of shallot (Allium ascalonicum) and garlic (Allium satium) on the fasting insulin resistance index (FIRI) and intraperitoneal glucose tolerance test (IPGTT) of fructose-induced insulin resistance rats. Male albino Wistar rats were fed either normal or high-fructose diet for a period of eight weeks. Fasting blood glucose level, fasting blood triglyceride level, FIRI, and the area under the glucose tolerance curve were significantly elevated in fructose-fed animals. Fructose-induced insulin resistance rats treated by aqueous shallot or garlic extract (500 mg/kg body weight/day, i.p.) for duration of eight weeks. Control animals only received normal saline (0.9%). The results showed that neither shallot nor garlic extracts significantly altered the FIRI and the IPGTT at the fourth week after treatment. The fasting blood glucose in fructose-induced insulin resistance animals has been significantly decreased in 8-week treated animals by both shallot and garlic extracts. Shallot extract administration, but not garlic extract, for a period of eight weeks can significantly improve the intraperitoneal glucose tolerance and diminish the FIRI. These results indicate that shallot and garlic extracts have a hypoglycemic influence on the fructose-induced insulin resistance animals and aqueous shallot extract is a stronger hypoglycemic agent than the garlic extract

Comparison of Diagnostic Value of Sonourethrography with Retrograde Urethrography in Diagnosis of Anterior Urethral Stricture

BACKGROUND: In spite of the advanced imaging methods, MRI and CT-Scan, the role of ultrasonography is still unique in some fields of genitourinary tract diseases.AIM: This study was aimed at assessing this role in the evaluation of male urinary stricture, and comparison with standard retrograde urethrography (SUG).METHODS: This was a cross-sectional study. The patients include those who were suspected of anterior urethral stricture and were introduced assessed with imaging techniques (RUG). The patient underwent ultrasonography too. The results of both methods were compared. RUG was considered as the gold standard for this comparison.RESULT: Ninety-seven patients were studied. The mean age was 46.9 ± 11.7 years (range 21-88 years), in RUG, 22 patients (22.8%) and SUG 23 patients (23.7%) had a stricture, 3 cases with a stricture in RUG had not evidenced of stenosis in SUG. The mean length of urethral stricture in RUG was 12.9 ± 8.1 mm and in SUG was 8.1 ± 7.3 mm. The estimated length in RUG way was significantly higher than SUG way(P=0.025).The sensitivity and specificity in using of SUG were 86.6% and 94.6%, respectively.CONCLUSION: The result of this study showed stricture length measured by ultrasound is shorter than the length measured by RUG and the sensitivity and specificity in using of SUG was 86.6% and 94.6% respectively that due to the advantages it is an acceptable way

Zinc attenuates ecstasy-induced apoptosis through downregulation of caspase-3 in cultured TM3 cells: An experimental study

Background: 3, 4-Methylenedioxymethamphetamine (MDMA) is commonly known as the most famous amphetamine derivative. Objective: To evaluate the influence of zinc on MDMA-induced apoptosis and caspase- 3 gene expression in Leydig cell line (TM3). Materials and Methods: Leydig cells were studied in differenet treatment groups regarding MDMA (0, 0.5, 1, 3, 5 mM) and zinc (0, 4, 8, 16, 32 μM). By the way, the effective concentration was determined to be 5 mM for MDMA and 8 μM for zinc. Then, TM3 cells were cultured in free medium as control (group I), medium containing MDMA (5 mM) (group II), zinc (8 μM) (group III), and zinc (8 μM) prior to MDMA (5 mM) (group IV) as well as in an untreated group (control). Cell viability was assessed at different times after cell culture by MTT assay. The mRNA expression level of caspase-3 was analyzed using real-time quantitative polymerase chain reaction. Results: The cellular viability was significantly reduced in TM3 cells after 24 hr and 48 hr exposure time regarding different concentrations of MDMA as well as high concentration of zinc (16 and 32 μM). Cell viability was increased in the group that received zinc (8 μM) before addition of MDMA (5 mM) compared to the control and MDMA groups. The mean ± SE of fold was 22.40 ± 7.5, 0.06 ± 0.02, and 0.009 ± 0.003 in MDMA, zinc, and zinc + MDMA groups, respectively. The mean of caspase-3 mRNA level was significantly increased in the MDMA-treated group (5 mM), while the relative expression of caspase-3 gene was significantly decreased in the zinc (8 μM) + MDMA (5 mM) group compared with the MDMA (5 mM) group (p = 0.001). Conclusion: Dietary intake of zinc has a protective effect against MDMA consumption in mouse. Key words: Zinc, MDMA, Apoptosis, TM3 cells

Postpartum depression and its correlation with spiritual health

Background and aims: Postpartum depression has a high prevalence in communities and needs great financial resources. On the other hand, the world views the spiritual health as a new and complementary dimension of health. The aim of this study was to investigate the correlation between postpartum depression and spiritual health. Materials and Methods: This correlational-analytic study was conducted on 152 women who gave birth 8 months ago, referred to Hajar Hospital, Imam Ali hospital, Molavi clinic, or other health centers of Shahrekord, and were also satisfied with participating in the study. They were selected by the simple sampling method and completed the Palutzian and Ellison Spiritual Health Questionnaire. Finally, the collected data were entered in SPSS software and descriptive statistics in addition to the Pearson correlation coefficient and K2 test were used to analyze the data. Results: In the present study, the mean age of the subjects was 29.15 (SD=5.45) with the range of 16-45 years. The mean scores of spiritual health and depression were obtained 96.3 and 8.94, respectively. The results of this study showed that the Pearson correlation coefficient was -75.5% (P˂ 0.001), demonstrating an inverse correlation between the scores of postpartum depression and spiritual health. Conclusion: In general, the correlation between postpartum depression and spiritual health was an inverse correlation and the level of depression decreased by an increase in spiritual health. It can be concluded that without the need for specific treatments, the level of postpartum depression can be reduced by increasing the level of spiritual health. Keywords: Spiritual health, Postpartum depression, Health, Psychiatric disorder

Job satisfaction among nurses in Iran: does gender matter?

Objective: Job satisfaction has attracted increasing attention of scholars of different disciplines in recent years. However, there are limited studies on nurses' job satisfaction and the impact of gender on nurses' satisfaction with their job, particularly in Iran as a developing economy. The paper aimed to examine job satisfaction among Iranian nurses. Specifically, this study aimed to explore how Iranian male and female nurses are different in their overall and the dimensions of their job satisfaction. Methods: The population for this study was nurses who worked in public and private hospitals in Tehran, the capital city of Iran. A sample of 146 nurses in eight different hospitals was selected to participate in this survey using the random sampling method. The sample consisted of 81 female and 65 male nurses. Results: Our findings revealed that job satisfaction of both male and female nurses was at a median level. Furthermore, the level of overall job satisfaction among female was low, and the mean score of the dimensions of their job satisfaction was lower than their male counterparts. Furthermore, according to the independent t-test analysis, the difference between all dimensions of job satisfaction of females and males was significant, except for their satisfaction with the specific job of nursing. Conclusion: The findings of this study suggested that overall female nurses' nursing job satisfaction was lower than males in all dimensions except for their satisfaction with their job. Yet, there was no significant difference between female and male nurses in all of the dimensions of their job satisfaction except for their satisfaction with their specific nursing job. This finding forms a basis for the development of management principles and practices, specifically in relation to human resource management in public and private hospitals in Iran