Basic Variables Research Articles

Novel methodology to assess the effect of contouring variation on treatment outcome.

Contouring variation is one of the largest systematic uncertainties in radiotherapy, yet its effect on clinical outcome has never been analyzed quantitatively. We propose a novel, robust methodology to locally quantify target contour variation in a large patient cohort and find where this variation correlates with treatment outcome. We demonstrate its use on biochemical recurrence for prostate cancer patients. We propose to compare each patient's target contours to a consistent and unbiased reference. This reference was created by auto-contouring each patient's target using an externally trained deep learning algorithm. Local contour deviation measured from the reference to the manual contour was projected to a common frame of reference, creating contour deviation maps for each patient. By stacking the contour deviation maps, time to event was modeled pixel-wise using a multivariate Cox proportional hazards model (CPHM). Hazard ratio (HR) maps for each covariate were created, and regions of significance found using cluster-based permutation testing on the z-statistics. This methodology was applied to clinical target volume (CTV) contours, containing only the prostate gland, from 232 intermediate- and high-risk prostate cancer patients. The reference contours were created using ADMIRE® v3.4 (Elekta AB, Sweden). Local contour deviations were computed in a spherical coordinate frame, where differences between reference and clinical contours were projected in a 2D map corresponding to sampling across the coronal and transverse angles every 3°. Time to biochemical recurrence was modeled using the pixel-wise CPHM analysis accounting for contour deviation, patient age, Gleason score, and treated CTV volume. We successfully applied the proposed methodology to a large patient cohort containing data from 232 patients. In this patient cohort, our analysis highlighted regions where the contour variation was related to biochemical recurrence, producing expected and unexpected results: (a) the interface between prostate-bladder and prostate-seminal vesicle interfaces where increase in the manual contour relative to the reference was related to a reduction of risk of biochemical recurrence by 4-8% per mm and (b) the prostate's right, anterior and posterior regions where an increase in the manual contour relative to the reference contours was related to an increase in risk of biochemical recurrence by 8-24% per mm. We proposed and successfully applied a novel methodology to explore the correlation between contour variation and treatment outcome. We analyzed the effect of contour deviation of the prostate CTV on biochemical recurrence for a cohort of more than 200 prostate cancer patients while taking basic clinical variables into account. Applying this methodology to a larger dataset including additional clinically important covariates and externally validating it can more robustly identify regions where contour variation directly relates to treatment outcome. For example, in the prostate case we use to demonstrate our novel methodology, external validation will help confirm or reject the counter-intuitive results (larger contours resulting in higher risk). Ultimately, the results of this methodology could inform contouring protocols based on actual patient outcomes.

Risk analysis of man overboard scenario in a small fishing vessel

One major accident scenario aboard fishing vessels is “man overboard” (MOB). Prevention of this accident scenario would reduce the high fatality rate in the fishing industry. Critical understanding of the risk factors is vital for a robust risk assessment of this accident scenario and to develop interventions. This paper presents the Objected-Oriented Bayesian Network (OOBN) application for risk assessment of the MOB scenario. The OOBN model is developed to probabilistically capture the key accident influencing factors in fragmented structures. The proposed methodology is demonstrated in an accident scenario, and the model captures the dynamic dependencies and interdependencies among basic variables and establishes their degree of influence on the accident occurrence probability. The vulnerability path was identified, and a pre-and post-accident intervention plan was proposed to minimize the accident occurrence and its associated risk. Applying the methodology provides vital safety-based information that could be adopted for small vessel operation and maritime administration regulation.

Thermal-microstretch elastic semiconductor medium with rotation field during photothermal transport processes

A mathematical novel model for elastic semiconductor medium with microstretch properties is investigated. The generalized model is studied in the context of photo-thermoelasticity theory when the semiconductor medium is excited. The governing equations describe the coupled between the propagation of the elastic-thermal-plasma waves when the thermo-microstretch elastic semiconductor material is studied during a rotation field. The linear medium has an isotropic properties. The photothermal transport processes occurs during a two-dimension elastic and electronic deformation when the microinertia of microelement is taken into account. The harmonic wave method can be used to obtain the general solutions for the basic physical variables. The complete analytical solutions of the considered variables are obtained when some mechanical-thermal and plasma conditions are applied on the boundary of the semiconductor medium. The numerical simulations of silicon and germanium media are constructed graphically with many comparisons according to a new parameters with thermal memories and rotation parameter.

The EU Child Cohort Network\u2019s core data: establishing a set of findable, accessible, interoperable and re-usable (FAIR) variables

The Horizon2020 LifeCycle Project is a cross-cohort collaboration which brings together data from multiple birth cohorts from across Europe and Australia to facilitate studies on the influence of early-life exposures on later health outcomes. A major product of this collaboration has been the establishment of a FAIR (findable, accessible, interoperable and reusable) data resource known as the EU Child Cohort Network. Here we focus on the EU Child Cohort Network’s core variables. These are a set of basic variables, derivable by the majority of participating cohorts and frequently used as covariates or exposures in lifecourse research. First, we describe the process by which the list of core variables was established. Second, we explain the protocol according to which these variables were harmonised in order to make them interoperable. Third, we describe the catalogue developed to ensure that the network’s data are findable and reusable. Finally, we describe the core data, including the proportion of variables harmonised by each cohort and the number of children for whom harmonised core data are available. EU Child Cohort Network data will be analysed using a federated analysis platform, removing the need to physically transfer data and thus making the data more accessible to researchers. The network will add value to participating cohorts by increasing statistical power and exposure heterogeneity, as well as facilitating cross-cohort comparisons, cross-validation and replication. Our aim is to motivate other cohorts to join the network and encourage the use of the EU Child Cohort Network by the wider research community.

Infectious diseases in India: assessing the role of household amenities and socio-demographic determinants

Infectious diseases continue to be a significant impediment in the attainment of sustainable development goals related to health. A lack of essential household amenities and social determinants are the primary cause behind the outbreak of infectious diseases in LMICs. The current study aimed to examine the socio-demographic determinants of infectious diseases vis-a-vis basic household amenities in India. This study was based on nationally representative data of ‘Key indicators of Social Consumption in India: Health’ conducted by the National Sample Survey Organisation between July 2017 and June 2018. The study measured the inicidence of various infectious diseases across basic household amenities and socio-demographic variables. Multivariate logistic regression is employed to analyse the association between the likelihood of a particular infectious disease and various intersectional variables. The study findings reveal that the lack of household amenities such as access to a toilet, clean drinking water, garbage disposal and socio-economic determinants such as area of residence, gender, poverty and age have a significant impact on the incidence of infectious diseases in India. Among various infectious diseases jaundice, malaria and others, including tuberculosis and typhoid, dengue fever and chikungunya, have a relatively higher incidence. Approximately 22.32% of the population do not have proper toilet facility, 45.56% have proper tap water facility, while 50% either use water from spring/well or other unprotected sources and about half of the population do not have any arrangement for garbage disposal. Among socio-demographic determinants, incidence of infections is relatively higher in rural areas, other backward classes (OBCs), males, children, and adults. The study findings outlined that there is a need for better government interventions towards reducing the burden of infectious diseases in India, particularly in rural areas.

Hibrit olarak alüminyum ve demir elektrotlar kullanarak elektrokoagulasyon prosesleri ile sulu çözeltilerden salisilik asit gideriminin araştırılması

In this study, salicylic acid, an important and widely used micropollutant in the pharmacy sector, removal by electrocoagulation process was investigated. Electrocoagulation and electroflotation processes are commonly used techniques in electrochemical treatment. The type of electrode material employing in electrochemical processes is one of the basic variables which determining the process performance. In the experiments, iron and aluminum plates were employed as a hybrid electrode combination in the electrocoagulation process. The effect of current density, initial pH, electrolysis time, and electrical conductivity were investigated. For this purpose, the current density was 20 A/m2 and 100 A/m2, initial pH 5-8, electrolysis time 2-50 min electrical conductivity 250-1000 µs/cm range and electrode connection type monopolar parallel (MP-P) salicylic acid removal efficiencies from aqueous solutions were investigated during the experimental studies. The best removal results were obtained at pH 6 with a current density of 80 A/m2, solution conductivity of 750 µs/cm, and 40 min of electrolysis time. In these operation conditions, operation cost, amount of sludge, and removal efficiency of salicylic acid were determined as 1.34 $/m3, 0.8 kg/m3, and 91.4%, respectively.

Covid-19's Impact on Society, Fashion Trends and Consumption

This paper aims to reflect about opinions and reports about the Covid-19 impact on society and on the fashion industry from retail, luxury market professionals and consumer behavior researchers. The pandemic impacts are analyzed under the perspective of consumer behavior and the demand for connection and affection from the isolation caused by the pandemic. Within these two dimensions, four basic variables emerge to formulate reflections on the future and to visualize opportunities, external threats and the impact on the internal strengths and weaknesses of different luxury, mass and differentiation business. The analysis was formulated based on books, research on websites in the digital sphere that encompass different opinions involved in the fashion world, as well as recent trend studies. To meet new consumer demands, a brand needs to be present in the digital environment and connect to its consumers on an emotional level through its purpose, values and communication, by means of virtual and physical channels in a fluid, direct and transparent way. Small businesses may have a greater capacity to adapt to the new post-Covid-19 moment, due to the agility of responding to adversities.

Mathematical Model and Numerical Simulation of hydrothermal Coupling for Unsaturated Soil Subgrade in the Seasonal Frozen Zone

The subgrade in the seasonal frozen zone is easy to induce uneven settlement, frost heave and thaw settlement under the action of environmental factors such as precipitation, evaporation, radiation, etc. The subgrade is mostly unsaturated soil. In non-saline soil areas, its diseases are mostly related to moisture migration and phase change in the soil. In order to study the moisture migration and temperature distribution of the unsaturated soil subgrade in the seasonal frozen zone, a hydrothermal coupling mathematical model was established. Based on the mathematical model, the hydrothermal coupling numerical simulation was carried out by using the COMSOL Multiphyscis finite element program, Given the basic parameters and variables, the model was solved by assigning the same initial and boundary conditions as the field test, and the simulation results were compared with the field test results to obtain very satisfactory temperature simulation results and a good fit between the moisture migration results and the field test values, proving the reliability of the mathematical model.

An orthogonal normal transformation of correlated non-normal random variables for structural reliability

In this paper, an efficient and explicit technique is proposed for transforming correlated non-normal random variables into independent standard normal variables based on the three-parameter (3P) lognormal distribution. In contrast with the classic Nataf transformation, the derived equivalent correlation coefficient in non-orthogonal standard normal space of the proposed transformation is expressed as an explicit formula, thereby avoiding tedious iteration algorithm or multifarious empirical formulas. Meanwhile, the applicable range of the original correlation coefficient is determined based on fundamental properties of the proposed expression of correlation distortion and the definition of correlation coefficient. The proposed transformation requires only the first three moments (i.e., mean, standard deviation, and skewness) of basic random variables, as well as their correlation matrix. Therefore, the proposed transformation can also be applied even when the joint distribution or marginal distributions of the basic random variables are unknown. Several numerical examples are presented to demonstrate the user-friendliness, efficiency, and accuracy of the proposed transformation applied in structural reliability analysis involving correlated non-normal random variables.

Three-dimensional large-deformation model of hard-magnetic soft beams

By embedding hard-magnetic particles in soft materials, hard-magnetic soft (HMS) materials have recently been fabricated and received great interest owing to their unique properties and help in versatile applications, e.g. soft robotics, wearable devices and biomedical implants. To fulfill the potential applications of HMS materials, it is critical to develop theoretical models for HMS structures and accurately predict their mechanical responses. In this work, we develop a novel three-dimensional (3D) large deformation model for HMS beams, which are actuated by magnetic fields. To capture the geometrically exact nonlinearities of the HMS beams, three Euler angles are taken into consideration and the couplings among stretching, bending and twisting deformations are incorporated. Despite the complexity of the problem, the obtained governing equations contain only three basic field variables and could be solved by the Galerkin method combined with the Trust-region-dogleg algorithm. The effectiveness of the proposed 3D model is demonstrated by comparing current results with those of several previous examples. It is found that the hard-magnetic particles embedded in the HMS beams tend to align regularly with the applied magnetic field direction by deforming the beams via bending, twisting, stretching and/or compression. The developed 3D theoretical model offers a powerful tool to investigate the extremely large deformations of HMS beams and the results could guide the design and optimization of HMS structures.

Farmers' behavior in reading and using risk information displayed on pesticide labels: a test with the theory of planned behavior.

Labels are the first source of information for the safe use of pesticides, but farmers rarely read labels before pesticide use. Using data from a sample of 300 orchard farmers in Meshginshar County, Iran, this study examined farmers' intention and behavior in reading and using risk information displayed on pesticide labels, using the theory of planned behavior (TPB). Only 26% of the respondents mentioned that they read pesticide labels. Most farmers showed a low tendency towards reading pesticide labels due to low education, advanced age, and label-related problems, i.e., use of too technical language and unclear texts with small and illegible fonts. From the three basic variables of the TPB, subjective norms and perceived behavioral control (PBC) showed a significant impact on intention, while attitudes showed no significant impact. The three main variables of the TPB explained 90.2% of the variance in farmers' intention to read and use the labels. Furthermore, PBC and intention significantly affected farmers' actual behavior in reading and using the labels, explaining 78.5% of the variance in farmers' actual behavior. Age, experience in farming, and experience in spraying were negatively correlated with all variables of the TPB. Findings provide new insights into farmers' behavior in reading pesticide labels by using for the first time the TPB. Pesticide manufacturers should consider the special conditions of subsistence farmers (low education and advanced age) when preparing pesticide labels and the extension services could use those findings to improve farmers' training in the use of pesticide labels. © 2021 Society of Chemical Industry.

Cultural Perspectives of Financial and Non-Financial Incentives

The present paper delineates an explanatory framework for the defining factors of incentives, both financial and nonfinancial, through the theory of human economic action and that of personality traits, which shape human goals and, ultimately, social identity. It is ascertained that three types of variables affect incentives: basic conditions (cultural change, etc.), basic values and needs (tradition, external values, etc.) and the dynamism of social identity, which includes the goals that are set. More specifically, the two basic variables that shape the incentives for human action and imbue dynamism in behavior relate to megalothymia—i.e., the need for acknowledgement of a person’s integrity along with the predisposition to be thought superior to others as well as the aspiration to a certain level of quality in life.

The dendrometric characteristics of oak woods in rural landscapes of the East Carpathians

The dendrometric characteristics are functions of tree age and ecological growth conditions. On relatively small areas of homogeneous sites, the stand age structure and the phytosocial interaction between the trees are the major factors influencing the stand characteristics. We hypothesise that the correlation between the basic dendrometric variables and tree age can be used as a yardstick discriminating silvopastoral oak woods from silvicultural stands managed for timber. The tree age, diameter at breast height (DBH), and height (H) were determined in 14 silvopastoral oak woods in the East Carpathian region, which were compared to the respective forest inventory data of 31 silvicultural oak stands. The correlation between DBH, H and their ratio – the slenderness index (si) and age of oaks – were very weak and insignificant compared to the conspicuous age effect on the dendrometric features in the forestry-grown stands, which can be explained by a more complex development dynamics and spatial structure of silvopastoral woods. The study implies that the habitat conditions and processes related to traditional husbandry are better harmonised with the intrinsic oak ecological adaptations than modern silvicultural treatments. Therefore, we advise to promote the revival of silvopastoralism in the Carpathian region as a cost-efficient way of perpetuating the rural ‘oakscape’, an outstanding bio-cultural landscape asset. Keywords: slenderness index, height-diameter, oak, cultural landscape, agroforestry, cattle grazing, wood-pastures

Farmers' intention to reduce pesticide use: the role of perceived risk of loss in the model of the planned behavior theory.

Numerous studies have examined how farmers are involved and behave in the use of pesticides, but what drives farmers' intention to diminish pesticide applications is mostly unknown. This study explored farmers' intention to minimize pesticide use, through the theory of planned behavior (TPB) and an adjusted form of the TPB, with perceived risk of loss as an additional variable to the original model. On a scale from 1 to 5, intention to reduce pesticide use had the lowest score of all variables (2.36), indicating that most farmers did not show intention to reduce pesticide use. Only 15.2% of the farmers were willing to reduce pesticide use, while 8.3% were undecided. Moreover, 58.2% of the farmers had high levels of perceived risk of loss by the reduction of pesticide use, which explained 37.3% of farmers' intention. From the three variables of the TPB, attitudes had the highest score (3.34), indicating slightly favorable attitudes toward pesticide reduction, while perceived behavior control had the lowest score (2.70), indicating poor control of pesticide reduction. Also, the three basic variables of the TPB were positively correlated (P < 0.01) with farmers' intention to reduce pesticides, while a negative correlation (P < 0.01) was noted between intention to reduce pesticides and perceived risk of loss. The three basic variables of the TPB were significant predictors of intention, capturing 54.7% of the variation in farmers' intention. Adding perceived risk of loss as a construct to the TPB improved the predictive ability of the original model. Poor control of pesticide reduction (high-perceived barriers) and high perceived risk of loss drive farmers' intention to reduce the use of pesticides. Advancing alternative crop protection methods focusing on agro-ecology and integrated pest management should be included in the work of extension services.

Reliability Estimation of Cracked API 5L X70 Pipeline Steel

The aim of this paper is to estimate the reliability of cracked pipeline steel grade API 5L X70 used for hydrocarbon transportation, by coupling a developed mechanical model, based in one hand on the simulation of cracked specimen, and an experimental result of tensile and charpy test, and in the other hand, based on a reliability model by using a first order reliability method (FORM). These pipes are produced by the Algerian company of manufacture of welded pipes (ALFAPIPE Annaba). The experimental task such as resilience and tensile test were carried out on specimens taken from a pipe in the longitudinal and the transversal directions. The resilience tests are carried out at different temperatures in order to estimate the fracture toughness of the material, basing on a global correlation. Besides, tensile tests are performed to bring out the mechanical characteristics of the material. After, the stress intensity factor is assessed using the analytical model of IRWIN. In the reliability analysis, the limit state function is attributed to the moment when the stress intensity factor estimated by Irwin mechanical model, is equal to the fracture toughness of the steel pipe. The basic random variables within the limit state function are assumed to follow a normal distribution in order to simplify the assessment. Then, the evaluation of the reliability index and the parameters sensitivities of the cracked pipelines steel are assessed.

Elastoplastic solution of drained expansion of a cylindrical cavity in structured soils considering structure degradation

An elastoplastic solution of drained cylindrical cavity expansion is presented based on a well-known critical state model for soils exhibiting a natural structure. The model referred to as the structured Cam-clay (SCC) model is capable of describing the properties of the soil structure and its subsequent stress-induced degradation. The asymmetric stiffness matrix of the elastoplastic constitutive equation for structured soils is derived due to the assumption of the non-associated plastic flow rule. The solution procedure is formulated by transforming the boundary value problem of cylindrical cavity expansion into the problem of solving four ordinary differential equations with three stress components and the specific volume as the basic unknown variables. The theoretical solution is numerically calculated and validated against the existing solution and finite element simulation results. Furthermore, the significance of the soil structure and its stress-induced degradation in the expansion response, and the interaction between the soil structure and overconsolidation are emphasized by extensive parametric analyses. The results demonstrate that the soil structure has a substantial influence on the cavity expansion response, and its degradation is closely related to overconsolidation. Particularly, among the solutions considered, the solution considering the soil structure provides higher effective stress values near the cavity surface due to the additional strength conveyed by the natural structure.

Safety factor for the Eurocode 2 punching resistance model

This paper deals with an evaluation of the generalised partial safety factor for resistance properties by using a statistical determination of a resistance model for predicting the punching capacity. The factor takes the material, model and geometric uncertainties into account. The Eurocode 2 design model for the assessment of the punching resistance without shear reinforcement was statistically analysed using an extensive database of experimental tests. The correction factor b of the model and the coefficient of variation of the model errors were evaluated according to Annex D of EN 1990. The statistical parameters of the basic variables in the resistance functions were assumed according to the recommendations of the Joint Committee on Structural Safety Probabilistic Model Code. The comparison of the safety factors obtained with the material safety factor currently used reveals that the current factor 1.50 underestimates the values obtained for the design model analysed.

A randomized controlled trial of self-compassion versus cognitive therapy for complex psychopathologies

Third wave cognitive behavioural therapy has drawn attention to the value of interventions focusing on improved psychological functioning and wellbeing, rather than recovery or absence of disorder alone. The current study compared behavioural therapy combined with either self-compassion training or cognitive therapy (experimental treatment with standard treatment) in a randomized controlled trial for an initial presentation of a depressive disorder or post-traumatic stress disorder at a publicly funded outpatient unit. A battery of reliable and valid scales to assess the severity of the presenting problem and level of self-compassion were administered at both commencement and end of a 12-week treatment intervention. Basic sociodemographic variables were also recorded. Effective randomization was achieved for all variables except self-compassion, for which the standard treatment group reported higher levels than the experimental group. The greater efficacy of the experimental protocol was indicated by significant time by group interactions in severity measures over time in the experimental group relative to the standard group. This study contributes to a relatively fledgling literature on the therapeutic efficacy of self-compassion, providing both researchers and clinicians with valuable insight into the circumstances in which training in self-compassion may be of potential benefit when incorporated into standard practice. The trial was registered with the Australian New Zealand Clinical Trials Registry (TRN 12617000885392, June 16, 2017).

A Method for Online Identification of a Subset of Synchronous Generator Fundamental Parameters from Monitoring Systems Data

Monitoring systems are common in small and large power plants, providing measurements of basic electrical, mechanical and thermal variables. These measurements can be used for the identification of the synchronous generator parameters. In this paper, a simple method for the identification of a subset of synchronous generator parameters, using basic measurements provided by monitoring systems, is proposed. The identification is performed in normal operating conditions using a synchronous machine simplified model suited for operating conditions under small disturbances. Three identification models are derived, each one depending on a subset of parameters. Three optimization subproblems are then solved by minimizing the residues between each model output and a system measurement. The resulting nonlinear least squares problems are solved by the interior-point method taking into account constraints on the parameters range. A method is proposed to estimate the load angle which is required in the identification. Results are presented for synthetic data and real data, from a 25 MVA generator in a hydroelectric power plant.

Association of Lower Nutritional Status and Education Level with the Severity of Depression Symptoms in Older Adults-A Cross Sectional Survey.

The study analyzes the relationship between nutritional status and depression symptoms severity in the older population. A total of 1975 older outpatients (1457 women and 518 men, median age 75) were included in the study. Depression symptoms severity was assessed using the Geriatric Depression Scale (GDS). Participants were divided into two subgroups according to GDS score. Group A: 0–5 points—without depression symptoms (1237, W:898, M:339), and group B: 6–15 points—with depression symptoms (738, W:559, M:179). The nutritional status of the patients was assessed with Mini Nutritional Assessment (MNA) and basic anthropometric variables (waist, hips, calf circumferences, body mass index (BMI), waist to hip ratio (WHR), and waist to height ratio (WHtR)). Education years and chronic diseases were also noted. Women with higher depression symptoms severity had significantly lower MNA scores [A: 26.5 (24–28) (median (25%−75% quartiles)) vs. B:23 (20.5–26)], shorter education time [A:12 (8–16) vs. B:7 (7–12)], smaller calf circumference [A:36 (33–38) vs. B: 34 (32–37)], and higher WHtR score [A:57.4 (52.3–62.9) vs. B:58.8 (52.1–65.6)]. Men with depression symptoms had lower MNA scores [A:26.5 (24.5–28) vs. B:24 (20.5–26.5)], shorter education [A:12 (9.5–16), B:10 (7–12)], and smaller calf circumference [A:37 (34–39), B:36 (33–38)]. In the model of stepwise multiple regression including age, years of education, anthropometric variables, MNA and concomitant diseases nutritional assessment, and education years were the only independent variables predicting severity of depression symptoms both in women and men. Additionally, in the female group, odds were higher with higher WHtR. Results obtained in the study indicate a strong relationship between proper nutritional status and education level with depression symptoms severity in older women and men.