Academic literature on the topic 'Relative Survival Coefficient'

Historical apparent recruitment rates can be estimated from time series of relative abundance and catch data using a simple difference equation in conjunction with assumed catchability coefficient and natural survival rate. Simple smoothing and optimal linear state estimation procedures can remove much of the variance in such estimates due to measurement error in relative abundance. The apparent patterns can be helpful to reveal important recruitment changes prior to availability of data for more complex stock assessments, provide checks on recruitments estimated by more complex assessment procedures, and provide warnings about biases in other assessment procedures that might result from using the relative abundance data for model tuning.

Background: Approximately one-third of colorectal cancer (CRC) patients will suffer recurrence. MiRNAs are small non-coding RNAs that play important roles in gene expression. We aimed to correlate miRNA expression with aggressive clinicopathological characteristics and survival outcomes in CRC. Methods: Tumour samples were extracted from 74 CRC patients. MiRNAs were quantified using real-time reverse transcriptase polymerase chain reaction. Descriptive statistics and Cox regression analyses were performed to correlate miRNA targets with clinicopathological and outcome data. Results: Aberrant miR-21 and miR-135b expression correlate with increased nodal stage (p = 0.039, p = 0.022). Using univariable Cox regression analyses, reduced miR-135b (β-coefficient −1.126, hazard ratio 0.324, standard error (SE) 0.4698, p = 0.017) and increased miR-195 (β-coefficient 1.442, hazard ratio 4.229, SE 0.446, p = 0.001) predicted time to disease recurrence. Survival regression trees analysis illustrated a relative cut-off of ≤0.488 for miR-195 and a relative cut-off of >−0.218 for miR-135b; both were associated with improved disease recurrence (p < 0.001, p = 0.015). Using multivariable analysis with all targets as predictors, miR-195 (β-coefficient 3.187, SE 1.419, p = 0.025) was the sole significant independent predictor of recurrence. Conclusion: MiR-195 has strong value in predicting time to recurrence in CRC patients. Additionally, miR-21 and miR-135b predict the degree nodal burden. Future studies may include these findings to personalize therapeutic and surgical decision making.

Abstract Background OS, the “gold standard” endpoint in oncology studies, is challenging to measure in earlier stages of BC because of considerably long survival. Further, during extended patient follow-up, treatment effect on OS can become impacted by multiple factors such as non-malignant causes of death, treatment cross-over, and post-progression treatments, making it difficult to isolate the true treatment effect. As an alternative, surrogate endpoints (SE) such as DFS, EFS, and pCR can be used to ascertain meaningful benefit in true endpoint (TE). While studies have previously explored the association of such SEs with OS in different BC populations, there is a dearth in literature of studies reporting on correlation in the NAdj/Adj settings in the HR+/HER2- BC population. The aim of this study is to conduct a correlation analysis between various SE-TE pairs (DFS/EFS vs OS, pCR vs OS and pCR vs DFS/EFS) in this population, from data reported in studies identified from a systematic literature review (SLR). For each pair of endpoints, both absolute and relative treatment effects were evaluated. Methods An SLR was conducted in NAdj/Adj setting for HR+/HER2- BC to identify studies that reported any two of pCR, DFS/EFS and OS. The search was carried out using MEDLINE, Embase, Cochrane Library databases (2000 onward), four BC-related conference proceedings (2018-2020) and clinical trial registries. Relative treatment effect sizes were quantified in terms of HRs for DFS/EFS and OS, and odds ratios (ORs) for pCR. Absolute treatment effects were analyzed in terms of survival probability of EFS/DFS and OS at landmark time points and pCR rates. A weighted least squares regression analysis was carried out to determine the strength of association between the various TE-SE pairs. The regression analysis was carried out on log scale for relative treatment effects and on linear scale for absolute treatment effects. Pearson correlation coefficient (r) was used to quantify the strength of association; coefficient of determination (R2) was also reported to evaluate goodness-of-fit. Sensitivity analyses were performed by considering linear scale (for relative outcomes only), using inverse of variance as weights, and by removing outliers. Results A total of 135 publications were identified in the SLR. Regression analysis showed that there is a statistically significant positive association (r= 0.91; 95%CI, 0.83-0.96, p &lt;0.0001) between log(HROS) and log (HRDFS/EFS), with R2 = 0.83. The correlation between log (HRDFS/EFS) and log(ORpCR) was not strong (r= 0.24; 95% CI, -0.63-0.84; p, 0.603). Correlation of ORpCR with HROS was not conducted due to inadequate data points (n=3). For the absolute outcomes, landmark DFS/EFS at 1 year and 2 years were each found to be moderately correlated with OS at 4 and 5 years. The correlation between pCR rate and landmark DFS/EFS and OS was not strong. The association between the pairs of the endpoints was consistent across all the sensitivity analyses. Conclusions Results of this regression analysis suggest that relative treatment effect on DFS/EFS is strongly associated with relative treatment effect on OS in HR+HER2- BC and could be used as a surrogate for OS. Correlation analysis for HR(DFS/EFS) vs. HR(OS) and OR(pCR) vs. HR(DFS/EFS)Model# studies# observationsPearson coefficient, r (95% CI)p-valueCoefficient of determination, R2 (95% CI)Slope (95% CI)P-valueHRDFS/EFS vs. HROS24320.91 (0.83-0.96)&lt;0.00010.83 (0.69-0.89)0.99 (0.83-1.16)&lt;.0001ORpCR vs. HRDFS/EFS570.24 (-0.63-0.84)0.60.06 (0-0.47)0.23 (-0.86-1.31)0.6099 Citation Format: Anagha Gogate, Inkyu Kim, Sandip Ranjan, Amit Kumar, Eros Papademetriou, Hitesh Bhandari, Ravi Potluri. Correlation between pathologic complete response (pCR), event-free survival (EFS)/disease-free survival (DFS) and overall survival (OS) in neoadjuvant and/or adjuvant (NAdj/Adj) hormone receptor positive (HR+) and human epidermal growth factor receptor-2 negative (HER2-) breast cancer (BC) [abstract]. In: Proceedings of the 2021 San Antonio Breast Cancer Symposium; 2021 Dec 7-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2022;82(4 Suppl):Abstract nr P2-12-09.

Abstract:In survival models, when the factor of interest is a continuous variable or is expressed through a group of several variables, the classical measures of risk, i. e. relative risk and odds ratio, are not appropriate and there is no standard measure of dependence between survival and the considered factor. The Information Gain has been proposed by Linfoot (1957) and Kent (1983), giving any parametric model as a generalization of the squared product-moment correlation coefficient of the linear regression model with normal errors. By using simulation methods, we studied the statistical properties of the information gain as a measure of dependence, in the particular case of survival regression models. We suggest several efficient applications of this informational concept to some classical problems of regression analysis and prognostic analysis. Our ideas are illustrated through an example on the prognosis of idiopathic dilated cardiomyopathy.

The current study aims to compare the relationships of some biological parameters of young grass carp, Ctenopharyngodon idella (Valenciennes, 1844) fed on artificial diet and alfalfa in earthen ponds. These parameters included length-weight relationship, relative length and weight of the alimentary canal, condition factor and survival rate. Results of lengthweight relationship showed that no significant differences (P>0.05) were recorded for the t-test for the ideal value of 3 for fishes fed on artificial diet or alfalfa plant. The condition factor of young grass carp fed on artificial diet ranged between 0.021 to 1.074, while for fishes fed on alfalfa plant was 0.023 to 1.270 for allometric and Fulton’s condition factor, respectively. Also, there was no significant difference (P>0.05) for fishes fed on both diets in all biological parameters, the relative length of the alimentary canal for fishes fed on artificial diet (1.65) and on alfalfa plant (1.69), while the relative weight of the alimentary canal were 0.0285 and 0.0218 for fishes fed on both diets, respectively. Results also showed that the Zihler coefficient were 7.43 and 7.62, respectively. The survival rate was 100% for both treatments.

A higher degree of angiogenesis is associated with shortened survival in glioblastoma. Feasible morphometric parameters for analyzing vascular networks in brain tumors in clinical practice are lacking. We investigated whether the macrovascular network classified by the number of vessel-like structures (nVS) visible on three-dimensional T1-weighted contrast–enhanced (3D-T1CE) magnetic resonance imaging (MRI) could improve survival prediction models for newly diagnosed glioblastoma based on clinical and other imaging features. Ninety-seven consecutive patients (62 men; mean age, 58 ± 15 years) with histologically proven glioblastoma underwent 1.5T-MRI, including anatomical, diffusion-weighted, dynamic susceptibility contrast perfusion, and 3D-T1CE sequences after 0.1 mmol/kg gadobutrol. We assessed nVS related to the tumor on 1-mm isovoxel 3D-T1CE images, and relative cerebral blood volume, relative cerebral flow volume (rCBF), delay mean time, and apparent diffusion coefficient in volumes of interest for contrast-enhancing lesion (CEL), non-CEL, and contralateral normal-appearing white matter. We also assessed Visually Accessible Rembrandt Images scoring system features. We used ROC curves to determine the cutoff for nVS and univariate and multivariate cox proportional hazards regression for overall survival. Prognostic factors were evaluated by Kaplan-Meier survival and ROC analyses. Lesions with nVS > 5 were classified as having highly developed macrovascular network; 58 (60.4%) tumors had highly developed macrovascular network. Patients with highly developed macrovascular network were older, had higher volumeCEL, increased rCBFCEL, and poor survival; nVS correlated negatively with survival (r = −0.286; p = 0.008). On multivariate analysis, standard treatment, age at diagnosis, and macrovascular network best predicted survival at 1 year (AUC 0.901, 83.3% sensitivity, 93.3% specificity, 96.2% PPV, 73.7% NPV). Contrast-enhanced MRI macrovascular network improves survival prediction in newly diagnosed glioblastoma.

This study aimed to investigate the effect of different levels of antimicrobial peptides (AMPs) supplementation in the diet feed on growth performance, survival rate, biochemical parameters in swamp eels. Healthy fishes were randomly assigned to five groups feeding with different supplementation of AMPs (0, 200, 400, 600, or 800 mg/kg) in diets for 68 days. Results showed that relative weight gain, feed coefficient and survival rate were significantly (p<0.05) increased by supplementation of AMPs in feed. Level of protein (TP), triglyceride TG, alanine transaminase (ALT), alkaline phosphate (ALP), acid phosphate (ACP), superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) in the serum were significantly (p<0.05) improved in all AMPs treatments, while no significant difference was found between the control and AMPs 200 mg/kg. AMPs supplementation significantly enhanced (p<0.05) the survival rate and immune protection in swamp eels after challenged with Aeromonas hydrophila compared to the control group and eels fed with AMPs 800 mg/kg had the highest survival rate and immune protection (32.50 and 85.71%, respectively). The diets containing AMPs enhanced the survival rate, immune ability, and antioxidant capacity in swamp eels, indicate that an appropriate dosage of AMPs can be used as a potential alternative to antibiotics in swamp eels.

584 Background: The issue regarding the eventual correlation between DFS at earlier follow-up (i.e. 3-yrs) with 5-yrs OS has not actually been explored in trials addressing the role of taxanes in BC. All RCTs in which patients were randomized to receive a standard or a taxane-based regimen for early BC were analyzed to evaluate this topic. Methods: All phase III trials with at least 60 month follow-up were considered eligible. The correlation has been explored according to a linear regression model considering both each single outcome pair (DFS/OS) for all arms (extracted by curves), their differences, and each outcome Hazard Ratio (HR) or calculated Relative Risk (RRs), following 2 steps: 1) correlation between 5-yrs DFS and OS (to confirm the evidence); 2) correlation between 3-yrs DFS and 5-yrs OS (predictive role). The correlation was estimated according to Pearson (r) and R2 coefficients (parametric) and Spearman (Rho) coefficient (non- parametric). A model to calculate the target sample size to determine 5-yrs OS benefit of 3%, 5% and 7%, respectively, was calculated as well. Results: Ten RCTs (17,067 patients) with available data for outcomes were gathered. For 5-yrs DFS/OS, a linear correlation was found between rates (r=0.74, R2=0.55; p<0.0001; Rho=0.83; p<0.0001), and HRs (r=0.90, R2=0.81; p<0.0001; Rho=0.91; p<0.0001). Three-yrs DFS correlates with 5-yrs OS, with both rates (r=0.81, R2=0.66; p<0.0001; Rho=0.92; p<0.0001), and RRs (r=0.84, R2=0.71; p=0.002; Rho=0.85; p=0.002). Three-yrs DFS and 5-yrs OS absolute differences strongly correlate (r=0.86, R2=0.74; p=0.001; Rho=0.84; p=0.002). The sample size model (on the basis of the r-coefficient=0.81), calculates 2,733, 863, and 389 pts to improve 3-yrs DFS of 4%, 7% and 10%, which means to improve 5-yrs OS of 3.2%, 5.7% and 8.1%, respectively. Conclusions: By these data, 3-yrs DFS is a reliable surrogate end-point for OS when testing new drugs in early BC, and is able to predict a late survival benefit. Thanks to the smaller patient sample size, RCTs with this design will provide early results in a shorter time period, allowing a faster data transfer to clinical practice. No significant financial relationships to disclose.

Forest crop cultivation of Crimean pine (Pinus pallasiana D. Don) was implemented in 2009–2020 on sandy and sand included soils in the steppe zone of the European part of Russia. During the analysis of the reasons for the low efficiency of reforestation, the authors proposed the hypothesis that the rules of planting recommended for Scots pine relative to the depth of rooting may not be acceptable for Crimean pine. The purpose of the work is to substantiate the necessity and the most optimal value of deepening the root collar of Crimean pine seedlings on hilly sands. Experimental forest cultures were planted in 2017. The depth of the plant collar relative to the soil surface was tested at 0, 2, 4, 6 cm, and until the seedling’s foliated part. The reference group was created by machine cultivation, which required a rooting depth of 6 cm or more. In the case of hand cultivation, the variants with planting depths of 2 and 4 cm had the highest rates of plant survival (94.2–94.6 % in the first year), plant safety (67.0–94.6 % in the fourth year), and their most even distribution over the silvicultural area (variation coefficient (υ) at 6.6–28.8 %). The lack of deepening and very deep planting by 6 cm led to a decrease in plant survival and preservation by 7.6–18.6 % with an increase in the range of the variation coefficient (υ, 10.2–60.6 %). The mechanized planting with a root collar depth over 6 cm gave the lowest number of preserved plants (58.4 % in the first year, 32.7 % in the fourth year), and the greatest range for the variation coefficient (υ, 30.5–70.1 %). An analytical equalization of the density of age dynamics showed that the predicted density would not reach the normative value with low and very deep planting. The established statistically significant differences in the survival rate of forest cultures throughout the observation period (tf = 2.12–4.38> t05 = 2.12–2.45) indicated the expediency of deepening the root collar. The optimal value is 2–4 cm, but until the seedling’s foliated part. For citation: Turchina T.A., Bannikova O.A. Creation of Forest Cultures of Crimean Pine (Pinus pallasiana D. Don) on the Hilly Sands in the Steppe Zone of Russia. Lesnoy Zhurnal = Russian Forestry Journal, 2023, no. 4, pp. 76–92. (In Russ.). https://doi.org/10.37482/0536-1036-2023-4-76-92

This thesis aims to understand the effects of women's residential location on breast cancer outcomes associated with screening, with a focus on women living in Queensland, Australia. It examines the spatial survival inequalities in health outcomes among these women by means of Bayesian spatial models and presents the inequalities with thematic maps across the state. The thesis investigated the spatial inequalities of various patient demographic, clinical and geographic factors as well as the intended use of cancer treatment among women with screen-diagnosed breast cancer.

The thesis concerns regression models related to the competing risks setting in survival analysis and deals with both the case of known specific causes and the case of unknown (even if present) specific causes of the event of interest. In the first part, dealing with events whose specific cause is known, competing risks modelling has been applied to a breast cancer study and some of the dynamic aspects such as time-dependent variables are tackled within the context of the application. The aim of the application was to detect an optimal chemotherapy dosage for different typologies of patients with advanced breast cancer in order to control the risk of cardiotoxicity. The attention was concentrated on the cumulative incidence probability of getting cardiotoxicity in a well-defined time period, conditional on risk factors. This probability was estimated as a function of the time-dependent covariate dosage. Within the context of the application, some problems of goodness-of-fit related to time-dependent covariates are discussed. The previous application gave rise to investigating the role of time-dependent covariates in competing risks regression models. There exist various types of time-dependent covariates, which differ in their random or deterministic development in time. For so-called internal covariates, predictions based on the model are not allowed, or they meet with difficulties. We describe a general overview of the state of the art, problems and future directions. Moreover, a possible extension of the competing risks model, that allows us to include a simple random binary time-dependent variable, in a multi-state framework, is presented. Inclusion of the sojourn time of an individual in a certain state as a time-dependent covariate into the model, is also studied. In the second part of the thesis, dealing with events whose specific cause is unavailable, regression models for relative survival are discussed. We study the nonparametric additive excess hazards models, where the excess hazard is on additive form. We show how recent developments can be used to make inferential statements about this models, and especially to test the hypothesis that an excess risk effect is time-varying in contrast to being constant over time. We also show how a semiparametric additive risk model can be considered in the excess risk setting. These two additive models are easy to fit with estimators on explicit form and inference including tests for time-constant effects can be carried out based on a resampling scheme. We analyze a real dataset using different approaches and show the need for more flexible models in relative survival. Finally, we describe a new suggestion for goodness-of-fit of the additive and proportional models for relative survival, which avoids some disadvantages of recent proposals in the literature. The method consists of statistical and graphical tests based on cumulative martingale residuals and it is illustrated for testing the proportional hazards assumption in the semiparametric proportional excess hazards model.

The aim of the paper was to determine the influence of root systems of chosen tree species found in the Polish Flysch Carpathians on the increase of soil shear strength (root cohesion) in terms of slope stability. The paper's goal was achieved through comprehensive tests on root systems of eight relatively common in the Polish Flysch Carpathians tree species. The tests that were carried out included field work, laboratory work and analytical calculations. As part of the field work, the root area ratio (A IA) of the roots was determined using the method of profiling the walls of the trench at a distance of about 1.0 m from the tree trunk. The width of the. trenches was about 1.0 m, and their depth depended on the ground conditions and ranged from 0.6 to 1.0 m below the ground level. After preparing the walls of the trench, the profile was divided into vertical layers with a height of 0.1 m, within which root diameters were measured. Roots with diameters from 1 to 10 mm were taken into consideration in root area ratio calculations in accordance with the generally accepted methodology for this type of tests. These measurements were made in Biegnik (silver fir), Ropica Polska (silver birch, black locust) and Szymbark (silver birch, European beech, European hornbeam, silver fir, sycamore maple, Scots pine, European spruce) located near Gorlice (The Low Beskids) in areas with unplanned forest management. In case of each tested tree species the samples of roots were taken, transported to the laboratory and then saturated with water for at least one day. Before testing the samples were obtained from the water and stretched in a. tensile testing machine in order to determine their tensile strength and flexibility. In general, over 2200 root samples were tested. The results of tests on root area ratio of root systems and their tensile strength were used to determine the value of increase in shear strength of the soils, called root cohesion. To this purpose a classic Wu-Waldron calculation model was used as well as two types of bundle models, the so called static model (Fiber Bundle Model — FIRM, FBM2, FBM3) and the deformation model (Root Bundle Model— RBM1, RBM2, mRBM1) that differ in terms of the assumptions concerning the way the tensile force is distributed to the roots as well as the range of parameters taken into account during calculations. The stability analysis of 8 landslides in forest areas of Cicikowicleie and Wignickie Foothills was a form of verification of relevance of the obtained calculation results. The results of tests on root area ratio in the profile showed that, as expected, the number of roots in the soil profile and their ApIA values are very variable. It was shown that the values of the root area ratio of the tested tree species with a diameter 1-10 ram are a maximum of 0.8% close to the surface of the ground and they decrease along with the depth reaching the values at least one order of magnitude lower than close to the surface at the depth 0.5-1.0 m below the ground level. Average values of the root area ratio within the soil profile were from 0.05 to 0.13% adequately for Scots pine and European beech. The measured values of the root area ratio are relatively low in relation to the values of this parameter given in literature, which is probably connected with great cohesiveness of the soils and the fact that there were a lot of rock fragments in the soil, where the tests were carried out. Calculation results of the Gale-Grigal function indicate that a distribution of roots in the soil profile is similar for the tested species, apart from the silver fir from Bie§nik and European hornbeam. Considering the number of roots, their distribution in the soil profile and the root area ratio it appears that — considering slope stability — the root systems of European beech and black locust are the most optimal, which coincides with tests results given in literature. The results of tensile strength tests showed that the roots of the tested tree species have different tensile strength. The roots of European beech and European hornbeam had high tensile strength, whereas the roots of conifers and silver birch in deciduous trees — low. The analysis of test results also showed that the roots of the studied tree species are characterized by high variability of mechanical properties. The values Of shear strength increase are mainly related to the number and size (diameter) of the roots in the soil profile as well as their tensile strength and pullout resistance, although they can also result from the used calculation method (calculation model). The tests showed that the distribution of roots in the soil and their tensile strength are characterized by large variability, which allows the conclusion that using typical geotechnical calculations, which take into consideration the role of root systems is exposed to a high risk of overestimating their influence on the soil reinforcement. hence, while determining or assuming the increase in shear strength of soil reinforced with roots (root cohesion) for design calculations, a conservative (careful) approach that includes the most unfavourable values of this parameter should be used. Tests showed that the values of shear strength increase of the soil reinforced with roots calculated using Wu-Waldron model in extreme cases are three times higher than the values calculated using bundle models. In general, the most conservative calculation results of the shear strength increase were obtained using deformation bundle models: RBM2 (RBMw) or mRBM1. RBM2 model considers the variability of strength characteristics of soils described by Weibull survival function and in most cases gives the lowest values of the shear strength increase, which usually constitute 50% of the values of shear strength increase determined using classic Wu-Waldron model. Whereas the second model (mRBM1.) considers averaged values of roots strength parameters as well as the possibility that two main mechanism of destruction of a root bundle - rupture and pulling out - can occur at the same. time. The values of shear strength increase calculated using this model were the lowest in case of beech and hornbeam roots, which had high tensile strength. It indicates that in the surface part of the profile (down to 0.2 m below the ground level), primarily in case of deciduous trees, the main mechanism of failure of the root bundle will be pulling out. However, this model requires the knowledge of a much greater number of geometrical parameters of roots and geotechnical parameters of soil, and additionally it is very sensitive to input data. Therefore, it seems practical to use the RBM2 model to assess the influence of roots on the soil shear strength increase, and in order to obtain safe results of calculations in the surface part of the profile, the Weibull shape coefficient equal to 1.0 can be assumed. On the other hand, the Wu-Waldron model can be used for the initial assessment of the shear strength increase of soil reinforced with roots in the situation, where the deformation properties of the root system and its interaction with the soil are not considered, although the values of the shear strength increase calculated using this model should be corrected and reduced by half. Test results indicate that in terms of slope stability the root systems of beech and hornbeam have the most favourable properties - their maximum effect of soil reinforcement in the profile to the depth of 0.5 m does not usually exceed 30 kPa, and to the depth of 1 m - 20 kPa. The root systems of conifers have the least impact on the slope reinforcement, usually increasing the soil shear strength by less than 5 kPa. These values coincide to a large extent with the range of shear strength increase obtained from the direct shear test as well as results of stability analysis given in literature and carried out as part of this work. The analysis of the literature indicates that the methods of measuring tree's root systems as well as their interpretation are very different, which often limits the possibilities of comparing test results. This indicates the need to systematize this type of tests and for this purpose a root distribution model (RDM) can be used, which can be integrated with any deformation bundle model (RBM). A combination of these two calculation models allows the range of soil reinforcement around trees to be determined and this information might be used in practice, while planning bioengineering procedures in areas exposed to surface mass movements. The functionality of this solution can be increased by considering the dynamics of plant develop¬ment in the calculations. This, however, requires conducting this type of research in order to obtain more data.

During current attempts of human survival for which, highly symptomatic propulsive professional, scientific and technological activity, relating to the rate of humans worn out in the light of their physical vs spiritual vs intellectual qualities, becomes even more significant, i.e. increases the multiplication coefficient as well as acceleration one. It is reasonable to conclude that in given circumstances of accelerated economic progress worldwide, simultaneously implying a geometric leap in the wear and tear of humanity, there is a convincing demand for establishing continuity of the revitalization process of psycho - physical - intellectual forces per capita. A crucial reason, which speaks in favor of the given claim is exclusive of a philanthropic nature, that is, it is a result of emotional activity as the need to exercise social responsibility. Human activities, among other things, are infrastructural assumptions created in parallel for the use of medical and health tourism services. Abstracting property form of ownership (state and/or private) regarding built accommodation facilities under medical and health tourism, we respect primarily as the need, and also the right of the human part of the capital, precisely, for the optimal renewal of spent components. After all, every form of human activity is immanent to the function of civilization achievement, that is, the natural need to live as humanely as possible. In the given sense, the built accommodation capacities of both medical and overall health tourism, indisputably, open their doors to people, that is to say, to their growing needs for optimal renewal of their spent physical, spiritual and intellectual strengths.

Supercritical fluids are widely used in aeronautic, astronautic and nuclear engineering. Active cooling is necessary for scramjet engines to survive the extreme heat generated in hypersonic flight. Regenerative cooling system, where engine fuel works as coolants and travels through the cooling tubes along the chamber wall, carrying away heat from the wall via heat convection and endothermic chemical reactions, is developed as an effective thermal management technique. In this paper, experimental results of convective heat transfer performances of aviation kerosene at supercritical pressures were presented. Stainless steel circular tubes having inner diameters of 1and 1.8 mm were investigated for pressures ranging from 3 to 4 MPa, mass flow rates from 1.87 to 2.41 g/s and heat fluxes from 285 to 365 kW/m2. It was found that the heat transfer coefficient increases with mass flow rate at the former part of the tube. However, as the Reynolds increases significantly at the latter part of the tube at relatively low mass flow rate, the heat transfer coefficient increases dramatically at the latter part of the tube at relatively low mass flow rate. The effect of heat flux on heat transfer is complicated, while the effect of pressure on heat transfer is insignificant. The experimental results also indicated that the heat transfer coefficient decreases with the reduction in tube diameter. The heat transfer behaviors in relation to changes in tube sizes might be caused by the buoyancy effect.

The increasing demands of better efficiency of modern advanced gas turbine require higher turbine inlet temperatures, which gives great challenges to turbine blade designers. However, the temperature limits of turbine blade material are not high enough to ensure its survival in such incredible operating temperature. Hence, both internal and external cooling approaches have been developed and widely used in today’s turbine blade. To internal cooling problems, a variety of cooling enhancement approaches, such as impingement and turbulators, are employed in order to meet the different needs in leading, middle and trailing region. One of the most critical parts in turbine blade is trailing edge where it is hard to cool due to its narrow shape. Pin-fins are widely used to cool the trailing edge of rotor and stator blades of gas turbine engine. Pin-fins offer significant heat transfer enhancement, they are relatively easy to fabricate and offer structural support to the hollow trailing edge region. The flow physics in a pin-fin roughened channel is very complicated and three-dimensional. In this work, we have studied the effect of channel orientation on heat transfer in a rotating wedge-shaped cooling channel using numerical methods. Qiu [1] studied experimentally heat transfer effects of 5 different angles of wedge shaped channel orientation for the inlet Reynolds number (5100 to 21000) and rotational speed (zero to 1000 rpm), which results in the inlet Rotation number variation from 0 to 0.68. They observed that compared to the non-rotating condition, there is about 35% overall heat transfer enhancement under highest rotation number. The above said results are validated using current studies with Computational Fluid Dynamics (CFD) revealed that rotation increases significantly the heat transfer coefficient on the trailing surface and reduces the heat transfer coefficient on the leading surface. This is due to the higher velocities associated with the converging geometry near trailing surface.

Abstract In the field of stochastic dynamics of marine structures, the determination of long-term extreme responses is a crucial aspect to ensure the desired level of structural reliability. The calculation of these responses requires precise knowledge of the environmental conditions and reliable methods to predict the values associated with a reliability target level. While there is a very precise method to determine the value of these extreme values, e. g. the full long-term analysis (FLTA), this approach is computationally expensive. Then, approximated methods are needed. One practical approach for the determination of the most relevant environmental conditions for extreme calculation is the environmental contour method (ECM). However, some limitations have been detected when this method is used for offshore structures that consider survival strategies e. g. offshore wind turbines (OWT). Lastly, a modified ECM procedure (MECM) has been developed with the purpose to bypass the limitations of the traditional ECM. This method is based on short-term simulations and through an iterative process by testing many environmental contours in the operational range allows finding an important wind speed with its corresponding return period and thus, the problem that traditional ECM has, is avoided. The environmental conditions, which are represented by a large number of parameters, are also an important aspect of extreme calculation. Whereas some of them are treated as stochastic values, some are considered deterministic and, therefore the existence of uncertainties in their measured/estimated values is inevitable. These uncertainties are addressed by adopting values recommended by standards and guidelines and, in practice, it is often necessary to be conservative when there is a lack of information about the specific site studied. Therefore, the understanding of the impact that these uncertainties can have on the loads/responses that govern the design of offshore structures, especially wind turbines, is of great relevance. In this work, the influence of uncertainty in the wind shear coefficient (WSC) is studied. This parameter is directly related to one critical environmental condition i. e. wind speed at hub height, and its influence in power production and fatigue loads has been documented in the literature, but, few cases have addressed their influence in bottom fixed OWT responses. This work seeks to highlight the relevance of an accurate selection of shear coefficient and, its influence on the probabilistic analysis of a bottom fixed OWT taking into account that considerable variations from recommended values may occur. Through the use of coupled simulations in FAST, the NREL 5MW wind turbine will be subjected to varying wind shear conditions, and the corresponding 50-yr long-term responses will be calculated considering the MECM to take into account the influence of the wind turbine survival mode. The extreme values are fitted from a Global Maxima Method (GMM). Finally, it is sought to relate the uncertainty in a relevant input parameter (i. e. WSC) with the uncertainties propagated to the output parameters (i. e. extrapolated long-term extreme responses).