The effect of black and green-tea extracts on dental-plaque forming Streptococci

زمینه و هدف: چای از پرمصرف‌ترین نوشیدنی‌ها در ایران است. اثرات ضد میکربی چای روی میکروارگانیسم‌های متعددی به اثبات رسیده است و یافتن فرآورده های طبیعی مانند مشتقات چای، که فاقد مخاطرات بر سلامت انسان باشند جهت کاهش ارگانیسم های پاتوژن ضروری بنظر می رسد. لذا این پژوهش با هدف بررسی اثر عصاره چای سیاه و سبز ایرانی بر استرپتوکوک‌های دهانی (استرپتوکوکوس موتانس، استرپتوکوکوس میتیس و استرپتوکوکوس سنگوییس) و اثر بازدارندگی آنها از تشکیل بیوفیلم، روی عوامل ایجاد کنندۀ پلاک‌های دندانی و پوسیدگی دندان انجام شد. روش بررسی: در این مطالعه تجربی پس از عصاره گیری نمونه ها با حلال متانول50 و جدا نمودن مجدد در فاز اتیل استـــات، عصاره ها توسط فیلتر 44/0 میکرون استریل شده و در 4 درجۀ سانتیگراد نگهداری شدند. از روش تهیۀ رقت های متوالی در محیط مایع برای محاسبۀ حداقل غلظت بازدارندگی و با تلقیح باکتری‌ها به درون ارلن های حاوی لام‌های شیشه‌ای برای سنجش تشکیل بیوفیلم استفاده شد. تشکیل بیوفیلم با کشت نمونه از روی لام ها و شمارش کلنی‌ها و همچنین مقایسۀ آنها در زیر میکروسکوپ فاز کنتراست با نمونۀ شاهد (محیط های تیمار نشده) مقایسه گردید. میانگین اندازه گیری‌ها در سه بار تکرار بیان و خطاها در هر نمونه با استفاده از آزمون آماری استاندارد (ANOVA) تعیین گردید. یافته ها: میکروسکوپ فاز کنتراست کاهش فوق العاده ای را در چسبیدن میکروارگانیسم های تیمار شده به یکدیگر در مقایسه با نمونۀ شاهد نشان داد. در غلظت 1 میلی گرم در میلی لیتر از عصارۀ چای سیاه بیوفیلم تشکیل نشد و غلظت 5/1 میلی گرم در میلی لیتر از عصارۀ چای سبز نیز بازدارندۀ کامل تشکیل بیوفیلم بود. عصاره های چای سیاه و سبز، به ترتیب در غلظت 5/2 و 3 میلی گرم در میلی لیتر اثر باکتریسایدی روی استرپتوکوکوس موتانس، استرپتوکوکوس میتیس و استرپتوکوکوس سنگوییس داشتند. نتیجه گیری: عصاره های چای به هر دو صورت چای سیاه و سبز خاصیت باکتریسایدی داشتند و اثر ضد میکربی چای سیاه بر روی استرپتوکوک های دهانی و ممانعت از تشکیل بیوفیلم توسط آنها بیشتر از چای سبز است

Static eccentricity fault detection in Flux Switching Permanent Magnet machines

This paper studies the effects of static eccentricity (SE) in Flux Switching Permanent Magnet (FSPM) Machines to propose a criterion for fault detection. SE is one of the most common mechanical faults in electrical machines on. In order to achieve this goal, the proposed machine is studied under different degrees of static eccentricity fault to analyze machine condition. Finite element modeling (FEM) as the most accurate numerical approach is used to obtain precise results. The magnetic flux distribution of rotor and stator are calculated. In addition, air-gap flux density as a parameter which has a direct impact on back-EMF is assessed by using finite element analysis (FEA). It is found that static eccentricity has noticeable influences on back-EMF of coils of the machine. Furthermore, Fourier analysis is performed in order to achieve appropriate index for the diagnosis process. The results are provided for the healthy machine and the machine with different values of SE and the proposed index has been derived for the fault detection process in the machine

Blood Lead Levels in Asymptomatic Opium Addict Patients; a Case Control Study

Introduction: One of the newest non-occupational sources of lead contamination is drug addiction, which has recently been addressed as a major source of lead poisoning in some countries. The present study aimed to investigate the blood lead level (BLL) of asymptomatic opium addicts.Methods: This case-control study was conducted during a one-year period to compare BLL of three groups consisting of opium addicts, patients under methadone maintenance therapy (MMT), and healthy individuals.Results: 99 participants with the mean age of 55.43±12.83 years were studied in three groups of 33 cases (53.5% male). The mean lead level in opium addicts, MMT and control groups were 80.30 ± 6.03 μg/L, 67.94 ± 4.42 μg/L, and 57.30±4.77 μg/L, respectively (p=0.008). There was no significant difference in BLL between MMT and healthy individuals (p=0.433) and also between opium addicts and MMT individuals (p=0.271).Oral opium abusers had significantly higher lead levels (p = 0.036). There was a significant correlation between BLL and duration of drug abuse in opium addict cases (r=0.398, p=0.022). The odds ratio of having BLL ≥ 100 in oral opium users was 2.1 (95% CI: 0.92 - 4.61; p = 0.43).Conclusion:  Based on the result of present study, when compared to healthy individuals, opium addicts, especially those who took substance orally had significantly higher levels of blood lead, and their odds of having BLL ≥ 100 was two times. Therefore, screening for BLL in opium addicts, particularly those with non-specific complaints, could be useful

Spatiotemporal variation of projected drought characteristics in Iran under climate change scenarios using CMIP5-CORDEX product

This study aims to assess the change of drought characteristics (intensity, duration, and frequency) under the effect of climate change in Iran using the modified standardized precipitation index (MSPI) and theory of runs on annual and seasonal scales for three near-future, mid-future (MF), and far-future climates. Hence, regional climate models extracted from South Asia-Coordinated Regional Climate Downscaling Experiments (CORDEX-SA) are applied. Regarding the result, MSPI could assign the standardized precipitation index (SPI) values better than the conventional form of SPI during the historical period (HP). The outcomes revealed that the northeast stations will experience a decrease in intensity (up to 24.57% in MF compared with HP) until 2100 at seasonal timescale, while the duration and frequency of drought will be increased. Although the greatest increase in intensity changes of droughts (up to 91%) until the end of the century will happen in the eastern and southwestern regions of Iran, these regions will face the maximum decrease in the duration (−30.54%) and frequency (−25%) of droughts compared with HP at seasonal timescale. In addition, regarding the outcomes of this study, strategies can be adopted to better manage water resources for various regions of Iran

The Association Between Serum Vitamin D Level and Nonalcoholic Fatty Liver Disease

Background: Nonalcoholic fatty liver disease (NAFLD) is a condition, in which triglyceride accumulates in hepatic cells without a history of alcohol consumption and is strongly associated with insulin resistance, obesity, diabetes mellitus, hypertension and dyslipidemia. The potential role of vitamin D in the pathogenesis of NAFLD has been reported. Objectives: The aim of this study was to determine the optimal vitamin D levels for prevention of NAFLD. Methods: In a cross-sectional study, 2,160 cases who referred to a university-affiliated health center were randomly selected and their demographic information, anthropometric and metabolic indices and also vitamin D levels were collected. Fatty liver was assessed by fatty liver index (FLI) and confirmed by FibroScan using controlled attenuation parameter (CAP). Based on the NAFLD score, the subjects were divided into two groups and the vitamin D cutoff point was calculated by ROC curve. Results: Based on the results, 745 patients (34.5%) had different degrees of fatty liver. Significant differences in the stiffness of liver tissue were observed between vitamin D categories (285.10 +/- 30.56 for severe, 251.82 +/- 42.63 for moderate and 201.02 +/- 36.08 for mild deficiency). According to the multivariate analysis, age, fasting insulin and vitamin D levels were found as the most significant factors in NAFLD pathogenesis. Vitamin D cutoff point was obtained 18 nmol/L in women and 21 nmol/L in men. Conclusions: The results indicated a significant association between vitamin D level and NAFLD score. Accordingly, increasing the public awareness to maintain a proper level of vitamin D may be a preventative strategy against NAFLD. Keywords Author Keywords:25-Hydroxyvitamin D; Nonalcoholic Fatty Liver Disease; Nonalcoholic Steatohepatitis; Obesity; Vitamin D Deficiency KeyWords Plus:25-HYDROXYVITAMIN D-3; INSULIN-RESISTANCE; STEATOHEPATITIS; EXPRESSION; SEVERITY; ALPHA; NAFLD; HISTOLOGY; CHILDREN; IMPAC

Sustainable building industry, construction practices and building operations: the role of the facility manager

Abweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in dt. SpracheDie Bauindustrie, in ihrem gesamten Umfang, leistet weltweit signifikante Beiträge zur wirtschaftlichen Entwicklung in jedem Land.Jedoch, während, diese Industrie, als Vervielfachungsfaktor der sozialen und wirtschaftlichen Entwicklung dient, verbraucht sie auf der einen Seite, die natürlichen, nicht erneuerbaren Vorräte des Planeten unnachhaltig und ist auf der anderen Seite, der Hauptverschmutzer unserer Umwelt und die Ursache für globale Sorgen, wie Dezimierung von natürlichen nicht erneuerbaren Energiereserven, sowie Luftverschmutzung und der daraus resultierenden Klimawandel und Erderwärmung. Zahlreiche Studien haben ergeben, dass beispielsweise, der Anteil des Gebäudebetriebes an CO2-Emissionen in vielen industrialisierten Ländern über 50% der Gesamt-CO2-Emissionen aus allen Industrien samt motorisiertem Verkehr ausmacht. Auf Grund derzeitiger Herausforderungen, die als Resultat von regionalen und globalen Umweltschäden und Luftverschmutzung die Erde konfrontieren, sind jetzt rigorose Maßnahmen notwendig, so dass die nächsten Generationen der Heutigen keine Nachlässigkeit vorzuwerfen haben.Es wird davon ausgegangen, dass durch Modifizierung der heutigen Vorgangsweisen, Technologien und wichtiger noch, durch Verlagerung der traditionellen Entscheidungsprozesse hinzu Umweltbewusstsein, die Bauindustrie sich allmählich in Richtung der Nachhaltigkeit bewegen könnte, wie zahlreiche Agenda, Conventionen und Abkommen der Vereinten Nationen definieren. Tatsache ist, dass durch gigantische Investitionen und Erschaffung von großen Gebäudekomplexen, wie z.b. Bürogebäude, in den letzten Jahrzehnten, eine Substanz von Baulichkeiten entstanden ist, die den heutigen Erwartungen und Anforderungen speziell im Bezug auf den Umweltstandards, Gesundheit und Sicherheit, nicht gänzlich gerecht wird. In diesem Zusammenhang, kann die Rolle des Facility Managers zur Erreichung der obgenannten Ziele nicht oft genug betont werden, insbesondere bei großen Gebäudekomplexen, die vor 3-4 Jahrzehnten gebaut worden sind. Nahezu alle diese Gebäudekomplexe, die in den letzten 5 bis 10 Jahren keiner wesentlichen Renovierungs- und Sanierungsarbeiten unterzogen worden sind, brauchen dringende Verbesserungsmaßnahmen, sollte effektive Nachhaltigkeit im Bezug auf Umwelt und Energieeinsatz erreicht werden wollen. Faciltiy Manager von solchen Gebäuden könnten die Entscheidungsprozesse eingehend Beeinflüssen, wenn es um die effektive Integration von ökologischen und ökonomischen Richtlinien und Durchführungsstrategien zur Erreichung der neuen Ziele geht. Des weiteren, genaue Informationen und Daten im Bezug auf Nutzerverhalten in großen Bürogebäuden sind wichtige Faktoren zur Optimierung der Verwendung von Medien und Energie. Facility Management's Planungen und Strategien können nicht in Isolation durchgeführt werden. Die Art des Verbrauches verschiedener Medien durch die Belegschaft solcher Gebäude muss immer berücksichtigt werden. Dafür ist das Sammeln von Informationen und Daten und deren Auswertung und Analyse als Eingangsparameter für die Planung und Implementierung, unabdingbar. Es ist nachweisbar, dass dadurch, erhebliche Einsparungen sowohl umweltbezogene als auch kostenmä[beta]ige im Verbrauch von Medien erreicht werden können. Mit anderen Worten, Nutzbarmachung von Informationen, sowie Beiträge anderer Beteiligter sollen die Eckpfeiler der Durchführung von umweltrelevanten Modernisierungsprojekten in großen Bürogebäuden sein.The building and construction industry, in general and globally, is one of the significant contributors to the overall economic development in every country. However, this industry, while having a multiplier effect on social and economic development, is on one hand consuming the natural non-renewable resources in a way that it can not be sustainable, and on the other, is a major polluter of the environment and the cause of major concerns on global issues, such as: depletion of natural non-renewable resources, air pollution and resultant climate change and global warming.Numerous studies have revealed that, for example, the share of building operations to the carbon dioxide emissions in industrialized countries is over fifty per cent of the total carbon dioxide emissions resulting from all industrial activities including motorized transport. In light of the current challenges facing the entire world as a result of regional and global environmental degradation and air pollution, rigorous measures should, therefore, be taken now so that the current generation is not blamed by the future ones for its negligence. It is believed that by modifying the current practices and technologies and, more importantly, by shifting the traditional decision-making processes towards environmental consideration and consciousness, the building and construction industry could gradually approach the goals of sustainability as defined by various United Nations and multilateral Agendas, Conventions, Protocols and/or Treaties.It is also an obvious fact that through huge investments and creation of large building complexes (e.g. office buildings) over the past few decades, a stock of built environment has been generated, which does not fully meet today's expectations and requirements, particularly when it relates to environmental, health and safety considerations. In this juncture, the role of facility managers, particularly for large building complexes built 3 - 4 decades ago, in achieving the above-mentioned goals cannot be overemphasized. Almost all of these building complexes that have not undergone any major renovation or refurbishment works in the past 5 to 10 years, need urgent improvements, if the expected sustainability criteria, particularly with regard to environment and energy, is to be met in an effective and efficient manner. In short, facility managers of such buildings could influence the decision-making processes immensely when it comes to the processes of the integration of environmental and economic policies as well as implementation strategies so that the new goals could be achieved effectively. Furthermore, accurate information and data on users' behaviors of large office buildings are important inputs for the optimization of the use of resources and utilities (e.g. energy). Facility managers' plans and strategies cannot be implemented in isolation. The way utilities are used by the occupants in such buildings should always be taken into consideration. As such, collection of information and data and their analysis - to be used as input for planning and implementation purposes - is indispensable. It has been proved that by so doing, considerable savings (both environmentally and financially) in the use of utilities (e.g. electricity for lighting) could be achieved if the above-mentioned issues are taken into consideration by facility managers. In other words, harnessing user information and all other stakeholders' inputs should be the cornerstone for implementing environmental and modernization projects in large office buildings.20

Investigating the Relationship between Borrowing from the Central Bank and Selected Internal Bank Variables in Iran: Application of the Dumitrescu-Hurlin Causality Test in Heterogeneous Panels

The purpose of this study is to examine the relationship between the two-way variable causality between the selected intra-bank variables including non-performing loans, loans and profitability with borrowing from the central bank. The purpose of this study is to investigate the relationship between two-way causality of selected intra-bank variables including non-performing loans, loans and profitability with borrowing from the central bank. In this study, the period of 2006-2016 for the 16 selected Iranian banks are used. Because of heterogeneity between banks of banking system, the method of assessing the causality relationship has regulated based on Dumitrescu-Hurlin Causality Test in Heterogeneous Panels. The results show that the variables of loans and profitability have a two-way (feedback) causality relation with borrowing from the central bank. There is a unilateral causality from non-performing loans to borrowing from the central bank and this borrowing is not the cause of non-performing loans. Therefore, stopping the banks' increasing and continuous borrowing flows is only possible by smart guidance and strict monitoring of the allocation of borrowed funds to the central bank's policy channels

Seasonal variation of radiation interception and radiation use efficiency in sugar beet (Beta vulgaris L.)

A high correlation existes between crop growth and the rate of radiation intercepted. The efficiency of radiation interception and absorption is dependent on leaf area index, light extinction coefficient and radiation use efficiency. In order to study mentioned coefficients a randomized complete block design with four replications was conducted during 2005 for different sugar beet cultivars (7233, 7112, 436, 276 and Rasoul) at Ferdowsi University of Mashhad experimental farm station. The cultivars were cultivated in eight rows with 50 centimeters distance in plots with 12 meter length and optimum condition of nutrients and irrigation. In addition to measuring the radiation above and under the canopy, the plots were sampled 9 times during growing season and leaf area index, total dry matter and finally light extinction coefficient and radiation use efficiency were measured. Mean maximum leaf area index was 3.51. The final yield of total dry matter for different genotypes varied from 15670 to 25920 kilogram per hectare. There were no significant differences among genotypes in light extinction coefficient and radiation use efficiency and their mean values were about 0.56 and 1.23 g.Mj-1 , respectively. Seasonal variation of radiation use efficiency was similar to leaf area index changes during the crop growth cycle and maximum radiation use efficiency was located before the reaching of maximum green leaf area index. Sugar content was increased proportional with total and root dry matter in most of crop growth cycle. Considering the importance of light extinction coefficient and radiation use efficiency in crop growth models and also their spatio-temporal variability under different management, it is necessary to perform more experiments in different years and locations with various treatments, to obtain a range of these coefficients for modeling studies

Reliability-based design and implementation of crow search algorithm for longitudinal dispersion coefficient estimation in rivers

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