Small to Medium Enterprise Business Leaders Managing Change

Organizational change is necessary for businesses to survive and prosper. One of the main reasons organizational change is unsuccessful is the inadequate leadership style used by business leaders. The purpose of this multiple case study was to explore leadership strategies business leaders used to manage change. The target population comprised a purposeful sample of 15 business leaders from various businesses located in the metropolitan area of Southern California. The conceptual framework for this study was the transformational leadership theory, which holds that leaders can use inspiration and motivation to inspire employees, especially during times of organizational change. A pilot study confirmed that all research questions were relevant to the research topic. Data were collected through face-to-face semistructured interviews and company document reviews. Data analysis included identifying relevant themes using a thematic approach to pinpoint, record, and examine patterns. Data were compared during each phase of the data collection process, revealing themes of managing employee\u27s needs, mentoring/training programs, motivation, influence, and communication. Member checking was used to validate themes and strengthen the trustworthiness of the interpretations. The results from this study may assist business leaders in facilitating organizational change. The implications for positive social change include the potential to contribute to job growth and employee prosperity in local communities

Canal Transportation and Centering Ability of Twisted File and Reciproc: A Cone-Beam Computed Tomography Assessment

Introduction: The purpose of this in vitro study was to compare the canal transportation and centering ability of Twisted File (TF) to that of Reciproc system. Methods and Materials: Forty noncalcified roots with mature apices, minimum length of 19 mm and an apical curvature of 15-30 degrees (according to Schneider’s method), from freshly extracted mandibular and maxillary teeth, were selected for this study. Samples were randomly divided into two groups (n=20) and canal preparation with either TF or Reciproc was performed according to manufacturers' instruction. Pre- and post-instrumentation cone-beam computed tomography (CBCT) images were captured and the extent of canal transportation and centering ability of the files were calculated, using the NNT Viewer software and Photoshop CS5, at levels of 3, 4, and 5 mm from the apex. The Mann-Whitney U test was used to analyze the statistical significance between the two groups. Results: One fracture occurred in the TF group. TF produced more transportation than Reciproc in both mesiodistal and buccolingual directions; however, the difference between the two systems were not statistically significant except for the TF group at 5-mm distance from the working length, where the difference was significant(P>0.05). Conclusion: Both file systems were able keep the original curvature of the canal and thus can be considered safe for clinical application

تاثیر مکمل ملاتونین در تمرینات شدید (مروری سیستماتیک)

Background and aim: Melatonin is an immune modulator that displays both pro- and anti-inflammatory properties. The aim of this study was to review the effect of melatonin supplementation on muscle injury, inflammation, and oxidative stress in intense exercise. The aim of this study was to review the effect of melatonin supplementation on muscle injury, inflammation, and oxidative stress in intense exercise. Methods: In this study, articles were searched in specialized databases, and all available resources were provided using appropriate keywords. Results: Studies have shown that exercise leads to oxidative stress and inflammation, which is directly related to the intensity of activity; Moderate-intensity exercise stimulates adaptive reactions, but strenuous exercise, which significantly increases the production of reactive oxygen species (ROS) and oxidative stress, may cause harm to athletes. The results showed that melatonin supplementation in athletes increased growth hormone, catalase (CAT), glutathione peroxidase (GPx), total antioxidant status (TAS), and decreased levels of cytokines TNFα and IL-6. Conclusion: The present study showed that melatonin oral supplementation in high-intensity exercise is effective in reducing oxidative stress (reducing fat peroxidation, with a significant increase in antioxidant enzymes) that leads to cell preservation and tissue damage and also accelerates recovery. This information also shows that melatonin has strong protective effects, prevents the occurrence of excessive inflammatory mediators, and prevents the effects of multiple inflammatory cytokines.سابقه و هدف: ملاتونین یک تعدیل‌­کننده سیستم ایمنی است که هر دو ویژگی پیش‌­التهابی و ضدالتهابی را نشان می‌­دهد. هدف از انجام مطالعه حاضر، مرور تاثیر مکمل ملاتونین بر آسیب عضلانی، التهاب و استرس اکسیداتیو در تمرینات شدید می­‌باشد. روش کار: در این مطالعه جستجوی مقالات در پایگاه­‌های تخصصی صورت پذیرفت و کلیه منابع در دسترس با استفاده از کلمات کلیدی مناسب در این مقاله مروری آورده شده است. یافته‌­ها: مطالعات به خوبی ثابت کرده است فعالیت ورزشی منجر به استرس اکسیداتیو و التهاب می‌­شود که این موضوع ارتباط مستقیمی با شدت فعالیت دارد؛ به طوری که فعالیت‌­های ورزشی با شدت متوسط، واکنش‌­های انطباقی را تحریک می‌­کند اما تمرینات شدید که تولید گونه‌­های فعال اکسیژن (ROS) و استرس اکسایشی را به طور قابل توجهی افزایش می­‌دهد، ممکن است باعث آسیب در ورزشکاران شود. نتایج نشان داد مصرف مکمل ملاتونین در ورزشکاران سبب افزایش هورمون رشد، آنزیم‌­های کاتالاز (CAT)، گلوتاتیون پراکسیداز (GPx)، ظرفیت آنتی‌­اکسیدانی کل (TAS) و کاهش سطوح سایتوکاین‌­های TNFα و IL-6 می‌­شود. نتیجه­‌گیری: مطالعه حاضر نشان داد که مکمل خوراکی ملاتونین در تمرینات با شدت بالا در کاهش میزان استرس اکسیداتیو موثر است (کاهش پراکسیداسیون چربی، با افزایش قابل توجه آنزیم­های آنتی‌­اکسیدانی) که منجر به حفظ سلول و کاهش آسیب بافتی و همچنین تسریع ریکاوری می‌­شود. این اطلاعات همچنین نشان می‌­دهد که ملاتونین اثرات محافظتی قوی داشته، از بروز بیش از حد واسطه‌‌های التهابی جلوگیری کرده و از تاثیرات سایتوکاین‌­های متعدد التهابی جلوگیری می‌کند

An In vitro Comparison of Apically Extruded Debris Using Reciproc, ProTaper Universal, Neolix and Hyflex in Curved Canals

Introduction: As a consequence of root canal preparation, dentinal chips, irrigants and pulp remnants are extruded into preradicular space. This phenomenon may lead to post endodontic flare-ups. The purpose of this study was to compare the amount of extruded debris with four endodontic NiTi engine-driven systems. Methods and Materials: Sixty mesiobuccal roots of maxillary molars with 15-30˚ curvature were divided randomly into four groups (n=15). Each group was instrumented up to apical size of 25 using Reciproc, ProTaper Universal, Neolix and Hyflex. Bidistilled water was used as irrigant and extruded debris was collected in pre-weighted Eppendorf tubes. Tubes were stored in incubator for drying the debris. Extruded debris were weighted in electronic microbalance with accuracy of 0.0001 g. The raw data was analyzed with one way analysis of variance (ANOVA) and Tukey’s HSD post hoc test. Level of significance was set at 0.05. Results: The debris extrusion with Reciproc files was significantly higher than the other groups (P<0.05). Hyflex significantly extruded less debris than other files (P<0.05). There was no significant difference between ProTaper Universal and Neolix regarding the amount of extruded debris (P=0.98). Conclusion: All systems extruded debris during the instrumentation. Reciproc system significantly extruded more debris. Caution should be taken when interpreting the results of this study and applying it to the real clinical situation.Keywords: Controlled Memory; Debris Extrusion; Reciprocating; Root Canal Preparation; Rotary Instrumentatio

Comparing parental monitoring, affiliation with delinquent peers, and high-risk behaviors in single-parent and two-parent male adolescents

Single-parent families maybe exposed of personal, interpersonal and family problems. Thus, the aim of the current research wasthe comparison of parental monitoring, affiliation with delinquent peers and high risk behaviors between single parent and two-parent adolescents. 100 single-parent adolescents and 100 two-parent adolescents in Eslamabad-e Gharb city of Kermanshah, Iran, were selected through Convenience sampling method, and responded to parental monitoring and affiliation with peers delinquent questionnaires and adolescent risk-taking scale. The results showed a significant difference between single parent and two-parent adolescent in terms of all three compared variables. Actually, single parent adolescents obtained lower score in parental monitoring and higher scores in affiliation with delinquent peers and high risk behaviors in comparison with two-parent adolescents. According to the results, it can be said that single-parent families are more exposed to problems. Therefore interventions to teach appropriate parenting style forparentsof single-parent adolescents and proper trainingsareessentialto prevent affiliation with delinquent peers and high risk behaviors among single-parent adolescents.Single-parent families maybe exposed of personal, interpersonal and family problems. Thus, the aim of the current research wasthe comparison of parental monitoring, affiliation with delinquent peers and high risk behaviors between single parent and two-parent adolescents. 100 single-parent adolescents and 100 two-parent adolescents in Eslamabad-e Gharb city of Kermanshah, Iran, were selected through Convenience sampling method, and responded to parental monitoring and affiliation with peers delinquent questionnaires and adolescent risk-taking scale. The results showed a significant difference between single parent and two-parent adolescent in terms of all three compared variables. Actually, single parent adolescents obtained lower score in parental monitoring and higher scores in affiliation with delinquent peers and high risk behaviors in comparison with two-parent adolescents. According to the results, it can be said that single-parent families are more exposed to problems. Therefore interventions to teach appropriate parenting style forparentsof single-parent adolescents and proper trainingsareessentialto prevent affiliation with delinquent peers and high risk behaviors among single-parent adolescents

Spatial, temporal, and demographic patterns in prevalence of chewing tobacco use in 204 countries and territories, 1990-2019 : a systematic analysis from the Global Burden of Disease Study 2019

Interpretation Chewing tobacco remains a substantial public health problem in several regions of the world, and predominantly in south Asia. We found little change in the prevalence of chewing tobacco use between 1990 and 2019, and that control efforts have had much larger effects on the prevalence of smoking tobacco use than on chewing tobacco use in some countries. Mitigating the health effects of chewing tobacco requires stronger regulations and policies that specifically target use of chewing tobacco, especially in countries with high prevalence. Findings In 2019, 273 center dot 9 million (95% uncertainty interval 258 center dot 5 to 290 center dot 9) people aged 15 years and older used chewing tobacco, and the global age-standardised prevalence of chewing tobacco use was 4 center dot 72% (4 center dot 46 to 5 center dot 01). 228 center dot 2 million (213 center dot 6 to 244 center dot 7; 83 center dot 29% [82 center dot 15 to 84 center dot 42]) chewing tobacco users lived in the south Asia region. Prevalence among young people aged 15-19 years was over 10% in seven locations in 2019. Although global agestandardised prevalence of smoking tobacco use decreased significantly between 1990 and 2019 (annualised rate of change: -1 center dot 21% [-1 center dot 26 to -1 center dot 16]), similar progress was not observed for chewing tobacco (0 center dot 46% [0 center dot 13 to 0 center dot 79]). Among the 12 highest prevalence countries (Bangladesh, Bhutan, Cambodia, India, Madagascar, Marshall Islands, Myanmar, Nepal, Pakistan, Palau, Sri Lanka, and Yemen), only Yemen had a significant decrease in the prevalence of chewing tobacco use, which was among males between 1990 and 2019 (-0 center dot 94% [-1 center dot 72 to -0 center dot 14]), compared with nine of 12 countries that had significant decreases in the prevalence of smoking tobacco. Among females, none of these 12 countries had significant decreases in prevalence of chewing tobacco use, whereas seven of 12 countries had a significant decrease in the prevalence of tobacco smoking use for the period. Summary Background Chewing tobacco and other types of smokeless tobacco use have had less attention from the global health community than smoked tobacco use. However, the practice is popular in many parts of the world and has been linked to several adverse health outcomes. Understanding trends in prevalence with age, over time, and by location and sex is important for policy setting and in relation to monitoring and assessing commitment to the WHO Framework Convention on Tobacco Control. Methods We estimated prevalence of chewing tobacco use as part of the Global Burden of Diseases, Injuries, and Risk Factors Study 2019 using a modelling strategy that used information on multiple types of smokeless tobacco products. We generated a time series of prevalence of chewing tobacco use among individuals aged 15 years and older from 1990 to 2019 in 204 countries and territories, including age-sex specific estimates. We also compared these trends to those of smoked tobacco over the same time period. Findings In 2019, 273 & middot;9 million (95% uncertainty interval 258 & middot;5 to 290 & middot;9) people aged 15 years and older used chewing tobacco, and the global age-standardised prevalence of chewing tobacco use was 4 & middot;72% (4 & middot;46 to 5 & middot;01). 228 & middot;2 million (213 & middot;6 to 244 & middot;7; 83 & middot;29% [82 & middot;15 to 84 & middot;42]) chewing tobacco users lived in the south Asia region. Prevalence among young people aged 15-19 years was over 10% in seven locations in 2019. Although global age standardised prevalence of smoking tobacco use decreased significantly between 1990 and 2019 (annualised rate of change: -1 & middot;21% [-1 & middot;26 to -1 & middot;16]), similar progress was not observed for chewing tobacco (0 & middot;46% [0 & middot;13 to 0 & middot;79]). Among the 12 highest prevalence countries (Bangladesh, Bhutan, Cambodia, India, Madagascar, Marshall Islands, Myanmar, Nepal, Pakistan, Palau, Sri Lanka, and Yemen), only Yemen had a significant decrease in the prevalence of chewing tobacco use, which was among males between 1990 and 2019 (-0 & middot;94% [-1 & middot;72 to -0 & middot;14]), compared with nine of 12 countries that had significant decreases in the prevalence of smoking tobacco. Among females, none of these 12 countries had significant decreases in prevalence of chewing tobacco use, whereas seven of 12 countries had a significant decrease in the prevalence of tobacco smoking use for the period. Interpretation Chewing tobacco remains a substantial public health problem in several regions of the world, and predominantly in south Asia. We found little change in the prevalence of chewing tobacco use between 1990 and 2019, and that control efforts have had much larger effects on the prevalence of smoking tobacco use than on chewing tobacco use in some countries. Mitigating the health effects of chewing tobacco requires stronger regulations and policies that specifically target use of chewing tobacco, especially in countries with high prevalence. Copyright (c) 2021 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.Peer reviewe

Spatial, temporal, and demographic patterns in prevalence of smoking tobacco use and attributable disease burden in 204 countries and territories, 1990-2019 : a systematic analysis from the Global Burden of Disease Study 2019

Background Ending the global tobacco epidemic is a defining challenge in global health. Timely and comprehensive estimates of the prevalence of smoking tobacco use and attributable disease burden are needed to guide tobacco control efforts nationally and globally. Methods We estimated the prevalence of smoking tobacco use and attributable disease burden for 204 countries and territories, by age and sex, from 1990 to 2019 as part of the Global Burden of Diseases, Injuries, and Risk Factors Study. We modelled multiple smoking-related indicators from 3625 nationally representative surveys. We completed systematic reviews and did Bayesian meta-regressions for 36 causally linked health outcomes to estimate non-linear dose-response risk curves for current and former smokers. We used a direct estimation approach to estimate attributable burden, providing more comprehensive estimates of the health effects of smoking than previously available. Findings Globally in 2019, 1.14 billion (95% uncertainty interval 1.13-1.16) individuals were current smokers, who consumed 7.41 trillion (7.11-7.74) cigarette-equivalents of tobacco in 2019. Although prevalence of smoking had decreased significantly since 1990 among both males (27.5% [26. 5-28.5] reduction) and females (37.7% [35.4-39.9] reduction) aged 15 years and older, population growth has led to a significant increase in the total number of smokers from 0.99 billion (0.98-1.00) in 1990. Globally in 2019, smoking tobacco use accounted for 7.69 million (7.16-8.20) deaths and 200 million (185-214) disability-adjusted life-years, and was the leading risk factor for death among males (20.2% [19.3-21.1] of male deaths). 6.68 million [86.9%] of 7.69 million deaths attributable to smoking tobacco use were among current smokers. Interpretation In the absence of intervention, the annual toll of 7.69 million deaths and 200 million disability-adjusted life-years attributable to smoking will increase over the coming decades. Substantial progress in reducing the prevalence of smoking tobacco use has been observed in countries from all regions and at all stages of development, but a large implementation gap remains for tobacco control. Countries have a dear and urgent opportunity to pass strong, evidence-based policies to accelerate reductions in the prevalence of smoking and reap massive health benefits for their citizens. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe

Temperature increase during post space preparation using different systems: An in vitro study

INTRODUCTION: The purpose of this study was to evaluate external root surface temperature rise during post space preparation using LA Axxess bur, Beefill pack System, and Peeso Reamer drill. MATERIALS & METHODS: The distal canals of forty-five extracted human permanent mandibular first molars were instrumented in crown-apical manner and obturated with lateral condensation technique. Teeth were then randomly divided into three groups according to post space preparation technique including: group 1. LA Axxess bur (Sybronendo Co., CA, USA), group 2 Beefill pack System (VD W Co., Munich, Germany) and group 3 Peeso Reamer drill (Mani Co., Tochigi-ken, Japan). Temperature was measured by means of digital thermometer MT-405 (Comercio Co., Sao Paulo, Brazil) which was installed on the root surfaces. Data was collected and submitted to one-way ANOVA and Post hoc analysis. RESULTS: Root surface temperatures were found to be significantly higher (7.3±2.7 vs. 4.3±2.1 and 4±2.4,) in samples of Beefill pack System compared with the two other groups (P<0.02). CONCLUSION: Using Beefill pack System during post space preparation may be potentially hazardous for periodontal tissues

Classification of Asthma Based on Nonlinear Analysis of Breathing Pattern.

Normal human breathing exhibits complex variability in both respiratory rhythm and volume. Analyzing such nonlinear fluctuations may provide clinically relevant information in patients with complex illnesses such as asthma. We compared the cycle-by-cycle fluctuations of inter-breath interval (IBI) and lung volume (LV) among healthy volunteers and patients with various types of asthma. Continuous respiratory datasets were collected from forty age-matched men including 10 healthy volunteers, 10 patients with controlled atopic asthma, 10 patients with uncontrolled atopic asthma, and 10 patients with uncontrolled non-atopic asthma during 60 min spontaneous breathing. Complexity of breathing pattern was quantified by calculating detrended fluctuation analysis, largest Lyapunov exponents, sample entropy, and cross-sample entropy. The IBI as well as LV fluctuations showed decreased long-range correlation, increased regularity and reduced sensitivity to initial conditions in patients with asthma, particularly in uncontrolled state. Our results also showed a strong synchronization between the IBI and LV in patients with uncontrolled asthma. Receiver operating characteristic (ROC) curve analysis showed that nonlinear analysis of breathing pattern has a diagnostic value in asthma and can be used in differentiating uncontrolled from controlled and non-atopic from atopic asthma. We suggest that complexity analysis of breathing dynamics may represent a novel physiologic marker to facilitate diagnosis and management of patients with asthma. However, future studies are needed to increase the validity of the study and to improve these novel methods for better patient management