فهرست مطالب حسین معین

To evaluate the acoustic performance of the muffler at zero flow, different methods of determining transmission loss were studied. Both numerical and experimental approaches were used to calculate transmission loss. The numerical method employed was the Herschel-Quincke tube method (case 1) as well as simulation methods using COMSOL (2) and ANSYS (3). The experimental approach utilized the transfer matrix method with the aid of software developed by the B&K software (4) and the sound card with MATLAB software (5) was used to calculate the transmission loss. Furthermore, the mesh independence of numerical methods and the uncertainty of the experimental method were examined. Results were evaluated between 20 and 1900 Hz, which is an appropriate frequency range and reliable range for evaluating mufflers and comparing different cases to transmission loss calculations. According to the results, the equivalent transmission loss for cases 1 to 5 is approximately 5.81 dB, 5.35 dB, 5.21 dB, 4.08 dB, and 3.77 dB, respectively Based on the results obtained, it can be concluded that the equivalent transmission loss of ANSYS and COMSOL numerical methods is almost consistent, and COMSOL simulation results in a 8% lower equivalent transmission loss than Herschel-Quincke's one-dimensional numerical method. Similarly, the equivalent transmission loss of experimental calculation methods indicates that the sound card approach has a 7.5% lower equivalent transmission loss than the B&K software approach.

Background and Aim:

 Cardiovascular complications in diabetes mellitus are one of the most common complications of this disease. The aim of this study was to determine the cumulative probability of occurrence of cardiac complications in type 2 diabetes mellitus using survival analysis in patients referring to the Diabetes Clinic, Bu-Ali Hospital, Zahedan, Iran.

This was a descriptive and analytical historical cohort study using the survival analysis method in 2020 on 410 patients referring to the Diabetes Clinic, Bu-Ali Hospital, Zahedan, Iran. Data were collected and analyzed using the SPSS-v21 software, the statistical tests being descriptive tests, followed by the Kaplan-Meier method and the Cox proportional hazards model of survival.

The results of this study showed that 122 individuals (29.7%) of the diabetic patients had cardiac complications. The median survival time (in months) of the occurrence of cardiac complications was found to be related to fasting and two-hour postprandial blood sugar levels (p<0.05). Further analysis of the data showed that two variables, namely fasting blood sugar and regular visits, remained in the final model of the multiple Cox regression.

The findings of this study showed that the cardiac complications of diabetes in the population studies are relatively high. Therefore, it is essential to plan and implement interventions aiming to change lifestyle and control regularly blood pressure, cholesterol and blood sugar in the patients in order to prevent the disease

Health care is one of the most complex activities that humans are involved with and are inherently associated with the potential to create the risk of being ill at the same time. In this study, the challenges in the field of patient safety culture and its strategies with regard to its dimensions are discussed.

This article is a narrative review article that searches for library resources and articles published in the years 2000-2022 using databases such as SID, Iran Medex, Elsevier, CINAHL, MEDLINE, PubMed, and related to safety culture. The patient was performed in Iran and the world. A total of 250 articles were extracted in this field and then 56 articles were used in this study according to the findings of the Patient Safety Culture Challenge.

Given the importance of patient safety culture in health care organizations, it seems that promoting it can improve the quality and performance of Iranian hospitals. Error, management support, staff shortages and inter-unit teamwork as priorities for action.

Patient safety at the hospital should be categorized as a strategic priority to be implemented in a detailed operational plan. It is then that safety in the organization which becomes a culture and everyone understands its importance and instills it in itself and all efforts in the organization center around this.

White spot syndrome virus (wssv) is the causing agent for white spot disease in shrimp and many crustaceans. This disease is highly contagious and can cause death within 3–10 days under normal culture conditions. Therefore, early diagnosis of the virus is a necessity.

Primers were designed for three regions of the virus genome and one region of the shrimp genome so that they could function together in a reaction. DNA was extracted from 40 samples of shrimp suspected of white spot disease. Primers were then optimized individually to detect white spot virus and after selecting the most suitable one, the virus was detected simultaneously by two pairs of primers. Shrimp genome replication primers were also used as internal control.

Among the designed primers, three pairs of primers were selected that amplified one fragment of the shrimp genome and two fragments of the virus genome. Of the 40 samples examined, 28 samples were positive (infected with the virus) and 12 samples were negative, which completely matched the results obtained with the reference kit.

To detect white spot virus, examination of two regions of the virus genome is sufficient and reduces the possibility of false negatives. It is also effective to use the shrimp genome to control DNA extraction and PCR steps. The single-step method (PCR) is preferable to the two-step method (Nested PCR) due to its reduced probability of contamination and ease of use.

Curriculum is one of the key elements of higher education for transferring knowledge, attitude and skills to students, which requires constant analysis and review. The world is witnessing the institutionalization of an efficient system, so this study aimed to compare the Nursing Program in Iran, England and Canada with practical suggestions for improving its quality.

In this comparative descriptive-comparative study, the main elements and important indicators of the Nursing Schools of Iran, England and Canada that were purposefully selected and analyzed based on Beredy model.

According to the findings, the overall goals and educational content of the study programs were somewhat similar, but the organization and formulation of the contents on one hand and on the other, the amount and type of content varied, which eventually created a totally different content. Also, despite numerous similarities in the techniques used in teaching and evaluation, various differences were observed depending on the level and objectives of the program.

It seems that although the educational curriculum of Iran is not in a bad position compared to the educational programs studied, in order to eliminate its shortcomings, such as objective selection, student evaluation, research, teaching methods and evaluation theory and practice need to be seriously reviewed and refined.

This study is trying to detect land cover changes in coastal areas of Bushehr province using cross classification and tabulation analysis. Land cover changes detection have done using Landsat satellite images belonging to the years 1987, 2001, 2006, and 2011. Results showed significant changes in the study area in the last 23 years by converting the 20807 ha of open spaces and 3724 ha of farm lands to residential lands. Also, 67890 ha from farmlands are converted to open space and other covers are changed too. The result of Kappa Index Agreement (KIA) analysis showed that most and least amounts of changes have been occurred in 2006-2010 (KIA: 0.9212) and 1988-2001 (KIA: 0.9506), respectively. Therefore, the results of this research shows unbalanced land cover changes in coastal areas of Bushehr province. The farmlands decline for increasing the residential development and loosing farm land are most important examples of changes. Therefore, with the current trend of degradation, environmental and social problems will threat the future situation of coastal areas of Bushehr province.