Distance-Based Formation Control of Multi-Agent Systems

This Ph.D. dissertation studies the distance-based formation control of multi-agent systems. A new approach to the distance-based formation control problem is proposed in this thesis. We formulated distance-based formation in a nonlinear optimal control framework and used the state-dependent Riccati equation (SDRE) technique as the primary tool for solving the optimal control problem. In general, a distance-based formation can be undirected, where distance constraints between pairs of agents are actively controlled by both adjacent agents, or directed, where just one of the neighboring agents is responsible for maintaining the desired distance. This thesis presents both, undirected and directed formations, and provides extensive simulations to verify the theoretical results. For undirected topologies, we studied the formation control problem where we showed that the proposed control law results in the global asymptotic stability of the closed-loop system under certain conditions. The formation tracking problem was studied, and the uniform ultimate boundedness of the solutions is rigorously proven. The proposed method guarantees collision avoidance among neighboring agents and prevents depletion of the agents' energy. In the directed distance-based formation control case, we developed a distributed, hierarchical control scheme for a particular class of directed graphs, namely directed triangulated and trilateral Laman graphs. The proposed controller ensures the global asymptotic stability of the desired formation. Rigorous stability analyses are carried out in all cases. Moreover, we addressed the flip-ambiguity issue by using the signed area and signed volume constraints. Additionally, we introduced a performance index for a formation mission that can indicate the controller's overall performance. We also studied the distance-based formation control of nonlinear agents. We proposed a method that can guarantee asymptotic stability of the distance-based formation for a broad category of nonlinear systems. Furthermore, we studied a distance-based formation control of uncertain nonlinear agents. Based on the combination of integral sliding mode control (ISMC) theory with the SDRE method, we developed a robust optimal formation control scheme that guarantees asymptotic stability of the desired distance-based formation in the presence of bounded uncertainties. We have shown that the proposed controller can compensate for the effect of uncertainties in individual agents on the overall formation

The relationship between the dimensions of job burnout with workplace physical environment and facilities among health workers in Golestan province

Background and Aims: Job burnout is the reaction of workers to chronic stress, with disastrous physical, psychological and adverse organizational consequences for employees. The aim of this study was to determine the relationship between the dimensions of job burnout and workplace physical environment and facilities among health workers in Golestan province.Materials and Methods: In the present cross-sectional study, 1141 respondents out of totally 1275 health workers in Golestan province participated in the survey. The sampling method was census. Data collection was done through a questionnaire dealing with physical environment and facilities of workplace as well as Maslach burnout inventory. Verbal consent was obtained from all participants and their responses werekept confidentially. Data were analyzed using SPSS and Chi-Square test at a significance level of 0.05Results: The results of the present survey indicate that the physical condition of the workplace was assessed as weak by 17.4% of participants. Similarly, 24.8% of respondents assessed health house facilities asweak. There were significant relationships between emotional exhaustion and physical condition as well as workplace facilities (p<0.005). The study, however, did not show a significant relationship between depersonalization and personal performance and workplace physical conditions and facilities (p>0.005).Conclusion: Regarding the relatively poor workplace physical conditions and facilities, it is recommended to improve these conditions in order to decrease health workers emotional exhaustion.Keywords: Job burnout, Physical environment, Facilities, Health house, Health worker, Golestan provinceFor downloading the full text please click her

Development and validation of a Semi-quantitative food frequency questionnaire among older people in north of Iran

Background: The study was conducted to assess reliability of modified semi-quantitative food frequency questionnaire (SQFFQ) as a part of the Amirkola Health and Aging Project (AHAP). Methods: The study was carried out in a sample of 200 men and women aged 60 years and older. A 138-item SQFFQ and two 24-hour dietary recalls were completed. The reliability of SQFFQ was evaluated by comparing eighteen food groups, energy and nutrient intakes derived from both methods using Spearman and Pearson’s correlation coefficients for food groups and nutrients, respectively. Bland-Altman plots and Pitman’s tests were applied to compare the two dietary assessment methods. Results: The mean (SD) age of subjects was 68.16 (6.56) years. The average energy intake from 24-hour dietary recalls and the SQFFQ were 1470.2 and 1535.4 kcal/day, respectively. Spearman correlation coefficients, comparing food groups intake based on two dietary assessment methods ranged from 0.25 (meat) to 0.62 (tea and coffee) in men and from 0.39 (whole grains) to 0.60 (sugars) in women. Pearson correlation coefficients for energy and macronutrients were 0.53 for energy to 0.21 for zinc in male and 0.71 for energy to 0.26 for vitamin C in females. The Pitman’s test reflected the reasonable agreement between the mean energy and macronutrients of the SQFFQ and 24-hour recalls. Conclusions: The modified SQFFQ that was designed for the AHAP was found to be reliable for assessing the intake of several food groups, energy, micro-and macronutrients

Assessment of human and physical resources in health houses and health-care centers providing emergency services: a study in Golestan province

Background and Aims: The right information on current situation such as physical space, equipment and manpower make it possible to assess emergency activities as well as to manage and provide qualified services to patients. The aim of this study was to determine human and physical resources in health houses and health care centers to provide emergency services in Golestan province. Background and Aims: The right information on current situation such as physical space, equipment and manpower make it possible to assess emergency activities as well as to manage and provide qualified services to patients. The aim of this study was to determine human and physical resources in health houses and health care centers to provideemergency services in Golestan province.Materials and Methods: The present descriptive cross sectional study was performed in Golestan province in 2012. The study population was health houses and health centers (both rural and urban). A multi-stage sampling method was exploited and required data were collected by check list through interviews and observations. All stagesof this research project were conducted ethically. Data were analyzed by descriptive statistics using SPSS 16.Results: The results of this study show that about 17.9 percent of health houses had no male health workers and a lack of female health workers was noticed in 2.4 percent of them. Similarly, there is not any nurse in 38.9 percent of health care centers. About 94.4 percent of centers suffered from having male nurse’s aid and 97.2 of them had no female nurse’s aid. The results further indicated that most of health houses were in a good level with regard to medical equipments (66.7%) and needed medications (63.6%). The majority of health care centers (63.9%) were indeed at intermediate level considering injection chamber and at very week level (52.4%) from the wound dressing point of view. The studied centers lacked the requisite medications and were at low levels. 74.33 percent of health care centers suffered from an apparent lack of dressing room facilities. About 85.3 percent of health centers showed ambulance deficit.Conclusion: According to the low levels of personal resources, equipment and physical spaces in studied health care centers, it is necessary to consider appropriate measures in order to improve the situation in these centers. Journal of Health in the Field, Vol.3, No.4, Winter 2016 Keywords: Personal resources, Physical resources, Health house, Health care center, Emergency services in Golestan province.Materials and Methods: The present descriptive cross sectional study was performed in Golestan province in 2012. The study population was health houses and health centers (both rural and urban). A multi-stage sampling method was exploited and required data were collected by check list through interviews and observations. All stages of this research project were conducted ethically. Data were analyzed by descriptive statistics using SPSS 16.Results: The results of this study show that about 17.9 percent of health houses had no male health workers and a lack of female health workers was noticed in 2.4 percent of them. Similarly, there is not any nurse in 38.9 percent of health care centers. About 94.4 percent of centers suffered from having male nurse’s aid and 97.2 of them had no female nurse’s aid. The results further indicated that most of health houses were in a good level with regard to medical equipments (66.7%) and needed medications (63.6%). The majority of health care centers (63.9%) were indeed at intermediate level considering injection chamber and at very week level (52.4%) from the wound dressing point of view. The studied centers lacked the requisite medications and were at low levels. 74.33 percent of health care centers suffered from an apparent lack of dressing room facilities. About 85.3 percent of health centers showed ambulance deficit.Conclusion: According to the low levels of personal resources, equipment and physical spaces in studied health care centers, it is necessary to consider appropriate measures in order to improve the situation in these centers.Journal of Health in the Field, Vol.3, No.4, Winter 2016Keywords: Personal resources, Physical resources, Health house, Health care center, EmergencyFor downloading the full text please click here

بررسی ارتباط ابعاد فرسودگی شغلی با محیط فیزیکی و امکانات محل کار در بهورزان استان گلستان

ackground and Aims: Job burnout is the reaction of workers to chronic stress, with disastrous physical, psychological and adverse organizational consequences for employees. The aim of this study was to determine the relationship between the dimensions of job burnout and workplace physical environment and facilities among health workers in Golestan province.Materials and Methods: In the present cross-sectional study, 1141 respondents out of totally 1275 health workers in Golestan province participated in the survey. The sampling method was census. Data collection was done through a questionnaire dealing with physical environment and facilities of workplace as well as Maslach burnout inventory. Verbal consent was obtained from all participants and their responses werekept confidentially. Data were analyzed using SPSS and Chi-Square test at a significance level of 0.05 Results: The results of the present survey indicate that the physical condition of the workplace was assessed as weak by 17.4% of participants. Similarly, 24.8% of respondents assessed health house facilities asweak. There were significant relationships between emotional exhaustion and physical condition as well as workplace facilities (p<0.005). The study, however, did not show a significant relationship between depersonalization and personal performance and workplace physical conditions and facilities (p>0.005).Conclusion: Regarding the relatively poor workplace physical conditions and facilities, it is recommended to improve these conditions in order to decrease health workers emotional exhaustion.زمینه و اهداف: فرسودگي شغلي واكنش کارکنان در برابر تنش هاي مزمن می‌باشد و تأثیرات مخرب جسمی و روحی و پیامدهای سازمانی نامطلوبی را برای شاغلین به همراه دارد. هدف از انجام این مطالعه تعیین ارتباط ابعاد فرسودگی شغلی با محیط فیزیکی و امکانات محل کار در بهورزان استان گلستان بود. مواد و روش‌ها: در این مطالعه مقطعی، از بین 1275 بهورز شاغل در استان گلستان، 1141 نفر در مطالعه شرکت نمودند. ابزار جمع‌آوري داده ها شامل دو پرسشنامه شرایط فیزیکی و امکانات محل کار و پرسشنامه فرسودگی شغلی مزلاچ بود. از تمام شرکت کنندگان رضایت شفاهی کسب گردید و پاسخهای آنان محرمانه باقی ماند. داده‌ها با استفاده از نرم‌افزار  SPSSو آزمون Chi-Square در سطح معنی داری 0/05آنالیز شد. یافته‌ها: 17/5% بهورزان شرایط فیزیکی محیط کار و 24/8% امکانات خانه بهداشت را ضعیف می دانستند. حیطه خستگی عاطفی با وضعیت محیط فیزیکی و وضعیت امکانات خانه بهداشت از نظر آماری ارتباط معنی داری داشت (0/005>p). حیطه های مسخ شخصیت و کاهش عملکرد فردی با وضعیت محیط فیزیکی و امکانات خانه بهداشت از نظر آماری ارتباط معنی داری نداشت (0/005<p). نتیجه‌گیری: با توجه به شرایط فیزیکی و امکانات نسبتاً نامطلوب خانه‌های بهداشت، به منظور بهبود و رفع خستگی عاطفی بهورزان بهبود شرایط فیزیکی و وضعیت امکانات خانه‌های بهداشت پیشنهاد می‌گردد

Anti-Cancer Effects of Probiotic Lactobacillus acidophilus for Colorectal Cancer Cell Line Caco-2 through Apoptosis Induction

Background: Colorectal cancer is one of the most common cancers worldwide. Probiotics are useful and non-pathogenic microorganisms in the gastrointestinal tract, which can show anticancer activity through the induction of apoptosis. This study aimed to evaluate the antiproliferative effects of Lactobacillus acidophilus probiotic on the Caco-2 colorectal cancer cell line. Methods: The supernatant (secreted metabolites) and bacterial extract of L. acidophilus probiotics were prepared and used as an anti-proliferative agent on the colorectal cancer cell line, Caco-2 in vitro. The effects of supernatant and extract of L. acidophilus were evaluated on the viability and proliferation of cancer cells using MTT assay. Moreover, morphological alterations of cancer cells treated with supernatant and extract of L. acidophilus were evaluated by an inverted phase contrast microscope. The mRNA expression levels of apoptosis-related genes (SURVIVIN and SMAC) in treated cancer cells and untreated controls were evaluated using the Real-Time PCR method. Results: The results showed that the supernatant and extract of L. acidophilus inhibited the viability and proliferation of cancer cells in a dose and time-dependent manner. Moreover, various morphological alterations were observed in the treated cancer cells, which are indicators of apoptosis induction. The mRNA expression of SURVIVIN and SMAC genes were significantly up-regulated and downregulated in the treated cancer cells, respectively. Conclusion: The results of the present study suggested that the supernatant and extract of L.acidophilus could inhibit the viability and proliferation of colorectal cancer cell line, Caco-2through induction of apoptosis, increase the survival rate of colon cancer patients

ارزیابی وضعیت منابع انسانی و فیزیکی خانه های بهداشت و مراکز بهداشتی درمانی در جهت ارائه خدمات اورژانسی: مطالعه ای در استان گلستان

Background and Aims: The right information on current situation such as physical space, equipment and manpower make it possible to assess emergency activities as well as to manage and provide qualified services to patients. The aim of this study was to determine human and physical resources in health houses and health care centers to provide emergency services in Golestan province. Background and Aims: The right information on current situation such as physical space, equipment and manpower make it possible to assess emergency activities as well as to manage and provide qualified services to patients. The aim of this study was to determine human and physical resources in health houses and health care centers to provideemergency services in Golestan province.Materials and Methods: The present descriptive cross sectional study was performed in Golestan province in 2012. The study population was health houses and health centers (both rural and urban). A multi-stage sampling method was exploited and required data were collected by check list through interviews and observations. All stagesof this research project were conducted ethically. Data were analyzed by descriptive statistics using SPSS 16.Results: The results of this study show that about 17.9 percent of health houses had no male health workers and a lack of female health workers was noticed in 2.4 percent of them. Similarly, there is not any nurse in 38.9 percent of health care centers. About 94.4 percent of centers suffered from having male nurse’s aid and 97.2 of them had no female nurse’s aid. The results further indicated that most of health houses were in a good level with regard to medical equipments (66.7%) and needed medications (63.6%). The majority of health care centers (63.9%) were indeed at intermediate level considering injection chamber and at very week level (52.4%) from the wound dressing point of view. The studied centers lacked the requisite medications and were at low levels. 74.33 percent of health care centers suffered from an apparent lack of dressing room facilities. About 85.3 percent of health centers showed ambulance deficit.Conclusion: According to the low levels of personal resources, equipment and physical spaces in studied health care centers, it is necessary to consider appropriate measures in order to improve the situation in these centers. Journal of Health in the Field, Vol.3, No.4, Winter 2016 Keywords: Personal resources, Physical resources, Health house, Health care center, Emergency services in Golestan province.Materials and Methods: The present descriptive cross sectional study was performed in Golestan province in 2012. The study population was health houses and health centers (both rural and urban). A multi-stage sampling method was exploited and required data were collected by check list through interviews and observations. All stages of this research project were conducted ethically. Data were analyzed by descriptive statistics using SPSS 16.Results: The results of this study show that about 17.9 percent of health houses had no male health workers and a lack of female health workers was noticed in 2.4 percent of them. Similarly, there is not any nurse in 38.9 percent of health care centers. About 94.4 percent of centers suffered from having male nurse’s aid and 97.2 of them had no female nurse’s aid. The results further indicated that most of health houses were in a good level with regard to medical equipments (66.7%) and needed medications (63.6%). The majority of health care centers (63.9%) were indeed at intermediate level considering injection chamber and at very week level (52.4%) from the wound dressing point of view. The studied centers lacked the requisite medications and were at low levels. 74.33 percent of health care centers suffered from an apparent lack of dressing room facilities. About 85.3 percent of health centers showed ambulance deficit.Conclusion: According to the low levels of personal resources, equipment and physical spaces in studied health care centers, it is necessary to consider appropriate measures in order to improve the situation in these centers.زمینه و هدف: مدیریت و ارزیابی فعالیتهای اورژانس و ارائه خدمات مطلوب به بیماران، تنها با داشتن اطلاعات صحیح از وضعیت موجود از قبیل فضا، تجهیزات و نیروی انسانی در مراکز اورژانس امکان پذیر است. هدف از انجام این مطالعه تعیین وضعیت منابع انسانی و فیزیکی خانههای بهداشت و مراکز بهداشتی درمانی در جهت ارائه خدمات اورژانسی بود. مواد و روشها: این مطالعه به صورت توصیفی و از نوع مقطعی انجام شد. جامعه پژوهش را مراکز بهداشتی درمانی شهری، روستایی و خانههای بهداشت استان تشکیل میداد. ابزار جمع آوری اطلاعات، چک لیست و روش نمونه گیری، چند مرحلهای بود. روش جمع آوری دادهها مشاهده و مصاحبه بود. تمام مراحل این طرح با رعایت موازین اخلاقی و پژوهشی انجام شد. جهت تحلیل دادهها از آمار توصیفی با استفاده از نرم افزار آماری SPSS.16 استفاده شد. یافته ها: بر اساس نتایج مطالعه، 17/9% خانههای بهداشت بهورز مرد و 2/4% بهورز زن نداشتند. همچنین 38/9% مراکز پرستار، 94/4% بهیار مرد و 97/2% بهیار زن نداشتند. اکثر خانه های بهداشت از نظر وضعیت تجهیزات و داروهای مورد نیاز اورژانس در سطح خوب قرار گرفتند. اکثر مراکز از نظر وضعیت تجهیزات اتاق تزریقات در سطح متوسط، از نظر وضعیت تجهیزات اتاق پانسمان در سطح خیلی ضعیف و از نظر وضعیت داروهای مورد نیاز، در سطح ضعیف قرار گرفتند. 74/33% مراکز اتاق پانسمان و 85/3% آمبولانس نداشتند. نتیجه گیری: با توجه به سطح ضعیف نیروی انسانی، تجهیزات و فضای فیزیکی مراکز بهداشتی درمانی، لازم است تدابیر مناسبی به منظور بهبود وضعیت موجود این مراکز اندیشیده شود.      &nbsp

Measuring progress from 1990 to 2017 and projecting attainment to 2030 of the health-related Sustainable Development Goals for 195 countries and territories: a systematic analysis for the Global Burden of Disease Study 2017

Background Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of “leaving no one behind”, it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990–2017, projected indicators to 2030, and analysed global attainment. Methods We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0–100, with 0 as the 2·5th percentile and 100 as the 97·5th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator.Background Efforts to establish the 2015 baseline and monitor early implementation of the UN Sustainable Development Goals (SDGs) highlight both great potential for and threats to improving health by 2030. To fully deliver on the SDG aim of “leaving no one behind”, it is increasingly important to examine the health-related SDGs beyond national-level estimates. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2017 (GBD 2017), we measured progress on 41 of 52 health-related SDG indicators and estimated the health-related SDG index for 195 countries and territories for the period 1990–2017, projected indicators to 2030, and analysed global attainment. Methods We measured progress on 41 health-related SDG indicators from 1990 to 2017, an increase of four indicators since GBD 2016 (new indicators were health worker density, sexual violence by non-intimate partners, population census status, and prevalence of physical and sexual violence [reported separately]). We also improved the measurement of several previously reported indicators. We constructed national-level estimates and, for a subset of health-related SDGs, examined indicator-level differences by sex and Socio-demographic Index (SDI) quintile. We also did subnational assessments of performance for selected countries. To construct the health-related SDG index, we transformed the value for each indicator on a scale of 0–100, with 0 as the 2·5th percentile and 100 as the 97·5th percentile of 1000 draws calculated from 1990 to 2030, and took the geometric mean of the scaled indicators by target. To generate projections through 2030, we used a forecasting framework that drew estimates from the broader GBD study and used weighted averages of indicator-specific and country-specific annualised rates of change from 1990 to 2017 to inform future estimates. We assessed attainment of indicators with defined targets in two ways: first, using mean values projected for 2030, and then using the probability of attainment in 2030 calculated from 1000 draws. We also did a global attainment analysis of the feasibility of attaining SDG targets on the basis of past trends. Using 2015 global averages of indicators with defined SDG targets, we calculated the global annualised rates of change required from 2015 to 2030 to meet these targets, and then identified in what percentiles the required global annualised rates of change fell in the distribution of country-level rates of change from 1990 to 2015. We took the mean of these global percentile values across indicators and applied the past rate of change at this mean global percentile to all health-related SDG indicators, irrespective of target definition, to estimate the equivalent 2030 global average value and percentage change from 2015 to 2030 for each indicator