32 research outputs found
مقایسه سطح سرمی آپلین در بیماران مبتلا به سندرم متابولیک معتاد و افراد مبتلا به سندرم متابولیک غیر معتاد
Influence of menstrual cycle and salivary ß-estradiol on volatile sulfur compound
BACKGROUND: ß -estradiol is a steroid sex hormone that plays important role in oral physiology. The aim of this study
was to determin the association of the menstrual cycle and salivary ß-estradiol with the production of volatile sulfur
compounds (VSC).
METHODS: In this cross-sectional study, twenty female dental students in good oral and general health were recruited for
evaluation of VSC, salivary flow, ß-estradiol concentration, oral dryness feeling and dysmenorrhea. Data were analyzed
by marginal homogeneity test and xtgee model.
RESULTS: The only covariates that significantly related to VSC were being at the follicular phase (B = -0.21, P = 0.02),
being at the pre-menstrual phase (B = -0.25, P = 0.01), stressfulness (B = 0.02, P = 0.01) and oral dryness feeling
(B = 0.34, P = 0.02). Salivary ß-estradiol was at the level of 59.7 31.2 in those having halitosis (VSC ≥ 75) while in
the others (VSC < 75) it was about 40.8 18.0 (P < 0.009). This difference was not statistically significant in multivariate
analysis.
CONCLUSIONS: The menstrual cycle, stress and oral dryness were the most important determinants of halitosis. The
salivary ß-estradiol level could not explain such relationship as its effect was eliminated considering the other factors.
KEY WORDS: Halitosis, menstrual cycle, ß-estradiol, volatile sulfur compound
A Methodology for Design and Adaptation of Infrastructure Under Deep Climate Uncertainty
Proper decision-making in design, and adaptation management of infrastructure is essential, in the face of environmental uncertainties. As and example, current climate change models yield a range of widely diverging projections, rendering the allocation of climate change readiness investments increasingly complicated. While a severe climate change scenario may necessitate extensive adaptation investments, realization of a mild or moderate environment after costly system modifications or early adoption of costly adaptation measures would also result in a sense of loss. An alternative approach is resorting to adaptive solutions that commence with reduced costs until the environmental circumstances become more evident.
With the goal of minimizing the sense of loss associated with decision-making, this research integrates the concept of regret into a decision-making framework. Regret serves as a quantifiable metric, capturing decision-makers' desire to mitigate the sense of loss resulting from making incorrect choices. Additionally, the framework incorporates the potential of gaining information over time about climate as it occurs through a dynamic programming scheme.
The research encompasses three studies. Firstly, common design and decision-making approaches are evaluated within the context of climate change. Specifically, an investigation into the nonstationary effects of wind load on structural reliability under the impact of climate change was conducted using several methods. The findings reveal that, under the worst scenario, the lifetime probability of failure can be around twice as high as the baseline without climate change. However, such a scenario-based analysis is not conclusive in decision-making.
To facilitate decision-making in the face of deep climate uncertainty, an innovative methodology is developed and then tested in a second study on bridge corrosion management. In this study, the methodology offers a straightforward decision-making approach when considering the implementation of costly corrosion protection measures in an unknown environment. Additionally, a sensitivity analysis aids in discerning project types and determining the optimal course of action, whether it involves waiting or investing in field testing.
Finally, the third study is an application of the methodology in the context of climate change by addressing the design and managed adaptation of a river-crossing bridge exposed to climate change-induced scour. The study showcases how the methodology can assess trade-offs among different design options and determine the optimal course of action, given the uncertainties surrounding future climate scenarios. By evaluating the trade-offs between inaction and costly adaptations, the research identifies conditions under which a wait-and-see approach is effective and when incorporating design flexibilities for future adaptations is warranted. Furthermore, the method's performance is evaluated, and a comparison of various decision-making methods for adaptation is presented. The analysis demonstrates that in the case study, incorporating the potential for information arrival can yield up to 10 million. Consequently, this framework empowers designers and asset managers to navigate the uncertainties of climate change in their decision-making processes effectively.
The outcomes of this research contribute to the advancement of decision-making approaches for infrastructure design and adaptation in the face of climate uncertainties. By integrating deep uncertainties into decision-making processes and proposing an innovative methodology, this research assists infrastructure owners, managers, and policymakers in enhancing the resilience and long-term sustainability of infrastructure systems in an uncertain future climate
The effect of Adrenalin administration on circulation stability in massive hemorrhage during operations
Although occurance of sudden and extensive hemorrhage is not a new subject, however due to high morbidity and mortality a high level of experience and expertise is required to control the situation. Single adrenaline injction that is fast and very potent has been used in order to maintain BP and help the use of blood saved in other parts of the body. Durring 1375 to 1381 a total of 8 patients were confronted with extensive and sudden hemorrhage during heart surgery. All of them experienced sudden arrest or a sharp decrease in blood pressure. Six cases had rupture of the descending aorta of which three had surgery due to coarctation of the aorta and three had PDA. In these patients one case had extensive cardiac rupture due to cutting of sternum and adhision and one with aortic aneurysm in upperabodmen. In this study, in coordination with the attending surgeon, the place of the rupture was first clamped and the patient was placed in trendelenburg position. Then adrenaline was injected (An average of 17 injections). At the same time other methods were used for the survival of the patient. Twenty minuts later the clamp had set in partial. Blood pressure was maintained at a minimun level during hemorrhage and HR and BP were recorded. None of the patients in this study had morbidity or mortality related to the hemorrhage, although one of the patients deceased later on due to the repeated hemorrhage. Therefore this method is presented as a way of controlling sudden and extensive hemorrhages.
Keywords: Adrenalin, Hemorrhagic shock, Cardiovascular collapse, Clamp of aorta, Ventilator-close heart operatio
AIRWAY COMPLICATION FOLLOWING BRONCOSCOPY AND TRACHEAL INTUBATION IN PEDIATRIC PATIENTS WITH COINCIDENTAL ASYMPTOMATIC SUBGLOTIC STENOSIS
<font><font color="#555555"><span style="font-size: 10pt; font-family: Tahoma">Introduction: The subglot is the most narrow part of the airway in children The most common cause of subglotic stenosis is due to trauma secondary to tracheal intubation. Many cases of subglotic stenosis are asymptomatic and discover only during an ordinary broncoscopy or tracheal intubation. Since the ordinary size broncoscope or tracheal tube can not be passed down the stenotic area, during broncoscopy or tracheal intubation in these patients the stenotic area of subglotic ring may be exposed to repeated mechanical trauma and postoperative airway obstruction which is the subject of the present research.<br />Methods: During a triennium, children escheduled for broncoscopy or tracheal intubation were investigated for the presence of subglotic stenosis and the development of postoperative airway obstruction. Frequency of postoperative airway problems were compared between the patients with and those without subglotic stenosis using Chi-Square method.<br />Results: Fourteen cases of subglotic stenosis were identified which all of them developed some forms of postoperative airway obstruction. Eighty six percent of these patient had a positive history for previous tracheal intubation. Nine patient out of 14 with subglotic stenosis required endotracheal intubation and seven of these patients underwent tracheostomy.Two patients died of accidental tracheal extubation.<br />Discussion: Broncoscopy and tracheal intubation in patients with asymptomatic subglotic stenosis is very dangerous and may lead to severe postoperative airway obstruction due to mechanical trauma of repeated broncoscopy or tracheal intubation. Therefore it is logical to manage the high risk patients (those with previous tracheal intubation) with extreme caution and preferably by an experienced physician.</span></font></font>