226 research outputs found
A MULTIPLE-MODEL APPROACH FOR SYNCHRONOUS GENERATOR NONLINEAR SYSTEM IDENTIFICATION
In this paper, a multiple model approach is proposed for the identification of synchronous generators. In the literature, the same structure often is used for all local models. Therefore, to obtain a precise model for the operating condition of the synchronous generator with severely nonlinear behavior, many local models are required. The proposed method determines the complexity of local models based on complexity of behavior of the synchronous generator at different operating conditions. There are two choices for increasing model precision at each iteration of the proposed method: (i) increasing the number of local models in one region, or (ii) increasing local model complexity in the same region. The proposed method has been tested on experimental data collected on a 3 kVA micro-machine. In the study, the field voltage is considered as the input and the active output power and the terminal voltage are considered as the outputs of the synchronous generator. The proposed method provides a more precise model with fewer parameters compared to some well known methods such as LOLIMOT and global polynomial models
Changing the Human Genome from the Perspective of Fundamental Moral Principles
زمینه و هدف: پروژه ژنوم انسانی در مفهوم عام خود پروژهای ژنتیکی است که با مهندسی ژنتیک یک انسان، امکان ایجاد هرگونه تغییر در نژاد انسان، اعم از ترمیم یا ارتقای ژنتیکی و حتی تولید انسان جدید بدون نیاز به نطفه پدر را فراهم میکند. از آنجا که تاریخ آغاز مطالعات ژنتیکی قدمت طولانی ندارد، مسأله شبیهسازی در حوزه امور مستحدثه قرار میگیرد. ملاحظات اخلاقی در واقع ناظر بر موانع اخلاقی است که در اثر ژنوم انسانی ممکن است پدید آید. بنابراین پژوهش حاضر درصدد است تا این نکات اخلاقی را مورد توجه قرار دهد.
مواد و روشها: برای بررسی موضوع حاضر از روش توصیفی ـ تحلیلی بهره برده شده است که در زمره روشهای کیفی به حساب میآید. روش حاضر با جمعآوری اطلاعات از متون و منابع اسنادی در حیطه اخلاقی و پزشکی به بررسی موضوع تغییر ژنوم انسانی میپردازد.
یافتهها: شبیهسازی انسان نیازمند در نظرگرفتن ملاحظات اخلاقی فراوانی است که از جهات مختلفی از جمله: عدم امنیت تکنیکی و پزشکی، سستشدن نهاد خانواده و نقض اصل کرامت انسانی و خدشهدارشدن نسب انسانی، عدم برخورداری از هویت فردی و رشد روانی کامل، ایجاد رویکرد نژادپرستانه و ایجاد نژاد برتر، نقض آفرینش انسان و دستکاری در کار خداوند را دربر میگیرد.
نتیجهگیری: قوانین و قواعد مربوط به شبیهسازی در حقوق ایران مبهم و دارای ابعاد مختلفی هستند که نمیتوان پشتوانه حقوقی محکمی برای حمایت از شبیهسازی فراهم آورد. تنها مواردی که دیده میشود، قواعد مربوط به ارث حمل، وصیت برای حمل و اقرار به نفع حمل است که در حوزه شبیهسازی از آنان نتایحی استخراج میشود. بنابراین از منظر حقوقی نیازمند وجود قوانین شفاف درباره شخصیت و هویت جنین و فرایند شبیهسازی هستیم. تأسیس قوانینی جهت شفافسازی سازوکارهای بهرهگیری از فناوری شبیهسازی امری ضروری است.Background and Aim: Human genome project in its general sense is a genetic project that with the genetic engineering of a human provides the possibility of any change in the human race, including genetic repair or improvement and even the production of a new human without the need for a father sperm. he does. Since the date of the beginning of genetic studies is not long, the issue of simulation is in the realm of emerging affairs. Ethical considerations actually address the moral barriers that may arise from the human genome. Therefore, the present study seeks to address these ethical points.
Materials and Methods: Descriptive-analytical method has been used to investigate the present issue, which is considered as a qualitative method. The present method examines the issue of human genome change by collecting information from texts and documentary sources in the field of ethics and medicine.
Findings: Human simulation needs to consider many ethical considerations from various aspects, including: lack of technical and medical security; Weakening of the family institution and violation of the principle of human dignity and damage to human lineage; Lack of personal identity and full psychological development; Creating a racist approach and creating a superior race; It includes the violation of human creation and the manipulation of God's work.
Conclusion: The rules and regulations related to simulation in Iranian law are ambiguous and have various dimensions that cannot provide strong legal support to support simulation. The only cases that can be seen are the rules related to inheritance of transportation, wills for transportation and acknowledgment in favor of transportation, from which results are extracted in the field of simulation. Therefore, from a legal point of view, we need clear rules about the personality and identity of the fetus and the simulation process. Establishing rules to clarify the mechanisms for using simulation technology is essential.
Please cite this article as: Vahedi J, Ahmadi SM. Changing the Human Genome from the Perspective of Fundamental Moral Principles. Bioethics Journal, Special Issue on Bioethics and Citizenship Rights 2020; 213-224
RANS K-? SIMULATION OF 2D TURBULENT NATURAL CONVECTION IN AN ENCLOSURE WITH HEATING SOURCES
ABSTRACT: This study is conducted to investigate turbulent natural convection flow in an enclosure with thermal sources using the low-Reynolds number (LRN) k-? model. This enclosure has a cold source with temperature Tc and a hot source with temperature Th as thermal sources, other walls of the enclosure are adiabatic. The aim of this study is to predict the effect of change in Rayleigh number, repositioning of cold and hot sources, and thermal sources aspect ratio on the flow field, temperature, and rate of heat transfer. To achieve this aim, the equations of continuity, momentum, energy, turbulent kinetic energy, and kinetic energy dissipation are employed in the case of 2D turbulence with constant thermo-physical properties except the density in the buoyancy term (Boussinesq approximation). To numerically solve these equations, the finite volume method and SIMPLE algorithm are used. According to the modeling results, the most optimal temperature distribution in the enclosure is seen when the hot source is below the cold source. With decreasing distance between hot and cold sources, heat transfer rate increases. The maximal heat transfer rate is derived via study of the heating sources aspect ratio. In constant positions of cold and hot sources on a wall, the heat transfer rate increases with increasing Rayleigh number (Ra=109-1011).
ABSTAK: Kajian ini dijalankan bagi mengkaji perubahan semula jadi aliran perolakan dalam tempat tertutup dengan sumber haba menggunakan model k-? nombor Reynolds-rendah (LRN). Bekas tertutup ini mempunyai dua sumber haba iaitu sumber sejuk dengan suhu Tc dan sumber panas dengan suhu Th, manakala dinding lain bekas ini adalah adiabatik. Tujuan kajian ini adalah bagi mengesan perubahan nombor Rayleigh, mengubah sumber sejuk dan panas dan nisbah sumber haba kepada kawasan aliran, suhu dan halaju perubahan haba. Bagi mencapai tujuan tersebut, persamaan sambungan, momentum, tenaga, tenaga kinetik perolakan, dan pengurangan tenaga kinetik telah dilaksanakan dalam kes perolakan 2D dengan sifat fizikal-haba berterusan (malar) kecuali isipadu terma keapungan (anggaran Boussinesq). Bagi menyelesaikan persamaan ini secara berangka, kaedah isipadu terhad dan algorithma MUDAH telah digunakan. Berdasarkan keputusan model, suhu distribusi optimal dalam bekas tertutup dilihat apabila sumber panas adalah kurang daripada sumber sejuk. Dengan pengurangan jarak antara sumber panas dan sejuk, kadar pertukaran haba meningkat. Kadar pertukaran haba maksima telah diperoleh melalui kajian nisbah aspek sumber pemanasan. Kadar pertukaran haba bertambah dengan bertambahnya nombor Rayleigh (Ra=109-1011), pada posisi tetap sumber sejuk dan panas pada dinding bekas
The Effect of Educational Intervention Based on the Health Belief Model on Medication Adherence among Patients with Diabetes Referred to a Diabetes Center in Zarand, Kerman
Background: Medication adherence in patients with diabetes is one of the main factors in diabetic patients care. The aim of this study was to investigate the effect of educational intervention based on the Health Belief Model (HBM) on medication adherence in patients with diabetes referred to a diabetes center in Zarand, Iran, in 2014.
Methods: This quasi-experimental study was performed on 100 patients with diabetes. The patients were divided into two groups (intervention and control). Data were collected using a researcher-made questionnaire including demographic variables, constructs of HBM, and the Morisky self-report questionnaire. The intervention group were divided into 5 groups including 8-12 patients, and according to the HBM, education was performed in four 60-90 minute sessions during one month. One month after the intervention, data were collected again and analyzed using descriptive statistics, linear regression, and Mann–Whitney U test.
Results: There was a significant difference in mean score of knowledge, perceived susceptibility, perceived severity, perceived benefits, perceived barriers, perceived efficacy, and cues to action between intervention and control groups after the intervention. Medication adherence was significantly related to the level of education (P=0.006). Among constructs of HBM, perceived self-efficiency was the strongest predicting factor (P=0.03). After the intervention, the mean scores of perceived sensitivity (P<0.001), perceived severity (P<0.001), perceived benefits (P<0.001), perceived barriers (P<0.001), perceived self-efficiency (P<0.0001), cue to action (P<0.0001), and medication adherence (P<0.0001) increased significantly.
Conclusion: Education based on the HBM was effective in increasing adherence to medical instructions in patients with type 2 diabetes
Perspective Chapter: A Global View of Natural Hazards Related Disasters
Natural hazards have become an increasingly prevalent threat to the world, with the frequency of recorded disasters rising in the recent years. Analyzing global data on natural hazards, identifying the most common and deadly events, and prioritizing decision-making on safe constructions, settlements, and factories are crucial to respond effectively to this trend. Using the EM-DAT database, this study examined primary natural hazards worldwide from 1900 to 2022, including earthquakes, volcanic eruptions, landslides, floods, droughts, wildfires, storms, and extreme temperatures. Statistical data show that storms have the highest frequency of occurrence (38%), droughts are the deadliest (53%), floods affect the most people (50%), and storms cause the most economic losses (41%). Asia has experienced the highest frequency, most deaths, and most total affected people due to natural hazards, followed by North America and Africa, respectively. North America has also seen the highest economic losses, followed by Asia and Europe. The study emphasizes the importance of databases like EM-DAT in advancing our knowledge of natural hazards worldwide, and supporting informed decision-making in risk assessment, disaster management, and mitigation efforts
Elevated factor VIII activity and venous thromboembolism in patients referred to the Iranian Blood Transfusion Organization: A case control study
ObjectiveA high plasma level of factor eight (FVIII) is a risk factor for venous thromboembolism (VTE). Since, there was no report about the association of elevated FVIII and VTE in Iranian population, the incidence of elevated FVIII and its association to VTE was evaluated.Materials and methods152 consecutive idiopathic VTE patients referred to the Iranian Blood Transfusion Organization (IBTO) and 130 healthy matched blood donors were studied. At least one confirmed idiopathic deep vein thrombosis (DVT) or pulmonary embolism (PE) was found among all cases. The blood samples were collected at least 3 months after DVT/PE diagnosis. The normal reference range was determined by using the Control samples of the donors. FVIII levels were measured using PTT based one-staged assay.ResultsThe FVIII levels in the cases and controls were 157.3±53.4 and 111.8±29.7, respectively. In cases, the lowest and the highest levels of FVIII were 66IU/dl and 364IU/dl, while they were 42IU/dl and 195IU/dl for the controls.There was no relation between gender, age and FVIII level in either group. The normal reference range for the controls was 52–171IU/dl. Considering the cut-off point as 180IU/dl, the elevated values were seen in 28.9% of the case group vs. 3.1% of the control group.ConclusionElevated factor VIII is likely to be a risk factor for VTE. Moreover, a new normal reference range for the Iranian population was defined
Breast Self – examination Predictors based on Precede Model: a study on female active health volunteers in Zarand City
Background & Objectives: Breast cancer is still the most common malignancy leading to women mortality worldwide and late diagnosis of breast cancer is still one of the main causes of death in affected women. One of the ways of early detection of breast cancer is breast self – examination. The aim of this study was to determine predicting factors of breast self - examination in female active health volunteers of Zarand/ Iran based on Precede model.
Methods: In this descriptive- analytical study, all participants of active heath volunteer program in health centers of zarand (110 women) were recruited. Data were collected using a researcher – made questionnaire consisted of two sections of demographic information and constructs of Precede model. Data were analyzed through SPSS22 and by using descriptive statistics (distribution and central tendency, frequency and percent) and analytic statistics (logistic regression).
Results: Mean age of participants was 37.76 ± 9.75 years and 81.8 % of them were married. Among Precede constructs, predisposing factors (self-efficacy: OR=1.46 and knowledge: OR=1.30) had the highest predicting role. Performing breast self - examination showed significant relationship with level of education (OR=0.01), family history of breast cancer (OR=0.02) and marital status (OR=0.04).
Conclusion: Since predisposing factors were the most important predicting factors for breast - self-examination, in planning health education programs, more attention should be paid to improving women's self - efficacy and increasing their awareness about breast self – examination.
Key¬words: Breast Self - Examination, Precede Model, Predicting, Health Volunteers
Citation: Khaleghi Mahani H, Fadakar MM, Ahmadi Tabatabaei SV, Mirzai M, Poursharifei A. Breast Self – examination Predictors based on Precede Model: a study on female active health volunteers in Zarand City. Journal of Health Based Research 2017; 3(1): 71-85
The Effect of Intravitreal Bevacizumab on Central Serous Chorioretinopathy
The aim of this study was to investigate the efficacy of Intravitreal Injection of Bevacizumab (IVB) in patients with Central Serous Chorioretinopathy (CSC) compared to the control group, after four months of injection. In this study, 30 eyes of 30 patients with CSC, who were in the age range of 23 to 50 years old (70% male subject) were included. Eligible patients were randomly allocated to the intervention (n = 15) and control groups (n = 15). Patients in the intervention group received a single dose injection of bevacizumab (1.25 mg in 0.05 mL), while patients in the control group were followed-up during the same time interval, without any medical interventions. Corrected Distance Visual Acuity (CDVA) and Central Macular Thickness (CMT) were evaluated as the primary outcome measures at the four-month follow-up. There was no statistically significant difference between the intervention and control groups regarding their baseline characteristics. Corrected Distance Visual Acuity was improved significantly in the intervention group (P < 0.001), while this improvement was not observed in the control group. Furthermore, greater improvement of CDVA was detected in the IVB group compared to the patients without injection (P = 0.018). The CMT findings were in line with CDVA changes in both groups, revealing a significant reduction of CMT only in the intervention group (P < 0.001). Also, thinner central retina was found in the intervention group compared to the comparison group, at the four-month follow-up (P < 0.001). Based on the findings, bevacizumab could be effective for improvement of both anatomical and functional outcomes in patients with CSC
Relationships among serum receptor of nuclear factor-kappaB ligand, osteoprotegerin, high-sensitivity C-reactive protein, and bone mineral density in postmenopausal women: osteoimmunity versus osteoinflammatory.
Abstract
OBJECTIVE:
The aim of this study was to investigate the correlations among circulating osteoprotegerin (OPG), the receptor activator of nuclear factor-kappaB ligand (RANKL), high-sensitivity C-reactive protein (hsCRP), and bone mineral density (BMD) in healthy postmenopausal women.
METHODS:
In a population-based study, highly specific enzyme-linked immunosorbent assay methods were used to evaluate the sera of 382 healthy Iranian postmenopausal women (mean age +/- SD, 58.7 +/- 7.5 y) for RANKL, OPG, hsCRP, degradation products of C-terminal telopeptides of type I collagen, and osteocalcin. BMD was determined for the lumbar spine (L2-L4) and the proximal femur using dual-energy x-ray absorptiometry.
RESULTS:
Circulating levels of OPG (r = 0.30, P < 0.001) and the RANKL/OPG ratio (r = -0.17, P < 0.001) were significantly associated with age. The geometric mean of hsCRP was 1.89 mg/L (SE, 1.05) in the population studied. There was a significant correlation between log(hsCRP) levels and body mass index (BMI; r = 0.36, P < 0.001). Multivariate linear analyses revealed that age (beta = -0.295, P < 0.001), BMI (beta = 0.464, P < 0.001), RANKL (beta = -0.105, P = 0.014), and OPG (beta = 0.098, P = 0.029) were the independent determinants for lumbar BMD (R(2) = 0.35). Age (beta = -0.250, P < 0.001), BMI (beta = 0.486, P < 0.001), and RANKL (beta = -0.110, P = 0.009) were independently correlated with femoral neck BMD (R(2) = 0.36). Age- and BMI-adjusted analysis by quartiles of log-transformed hsCRP did not reveal an association with BMD, serum levels of biochemical markers of bone turnover, RANKL, or OPG
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