Age and total and free prostate-specific antigen levels for predicting prostate volume in patients with benign prostatic hyperplasia

Objectives: To investigate the predictive values of free prostate-specific antigen (fPSA), total PSA (tPSA) and age on the prostate volume.

Methods: The data of 2148 patients with lower urinary tract symptoms were analyzed retrospectively. The patients who had transrectal ultrasonography guided 10 core biopsies owing to the findings obtained on digital rectal examination and presence of high PSA levels (PSA?=?2.5–10?ng/dl), and proven to have BPH histopathologically were included in the study. Age, tPSA, fPSA and the prostate volumes (PV) of the patients were noted.

Results: One thousand patients that fulfilled the inclusion criteria were included in the study. The PV of the patients were significantly correlated with age, tPSA and fPSA (p?r?=?0.307, p?r?=?0.382, p?r?=?0.296, respectively). On linear regression model, fPSA was found as a stronger predictive for PV (AUC?=?0.75, p?p?p?=?0.013).

Conclusions: Although tPSA is an important prognostic factor for predicting PV, the predictive value of fPSA is higher. PV can easily be predicted by using age, and serum tPSA and fPSA levels.     

Trust in Islamic Business-to-Business Relationships: Evidence from Indonesia

We examine the role of trust within Islamic culture in business-to-business relationships by exploring the link between credit officers’ trust in business customers and their financing decisions. In line with our framework, which is based on the fact that Islamic culture is characterized by a collectivistic approach and clan-based social structure, we find that value-based trust is more important than competence-based trust in explaining business relationships. The results support the argument that Islamic culture business relationships are grounded more on the principles, values and norms that a partner brings to the relationship than on business skills. Our results are robust to endogeneity and multilevel issues.     

Non-ignorable missing covariate data in survival analysis: a case-study of an International Breast Cancer Study Group trial

Summary.  Non-ignorable missing data, a serious problem in both clinical trials and observational studies, can lead to biased inferences. Quality-of-life measures have become increasingly popular in clinical trials. However, these measures are often incompletely observed, and investigators may suspect that missing quality-of-life data are likely to be non-ignorable. Although several recent references have addressed missing covariates in survival analysis, they all required the assumption that missingness is at random or that all covariates are discrete. We present a method for estimating the parameters in the Cox proportional hazards model when missing covariates may be non-ignorable and continuous or discrete. Our method is useful in reducing the bias and improving efficiency in the presence of missing data. The methodology clearly specifies assumptions about the missing data mechanism and, through sensitivity analysis, helps investigators to understand the potential effect of missing data on study results.     

The “diseased” activist's body as the site of trauma: Anti-racist struggles and the postrace academy

This paper is an autoethnographic account of the “racialized activist body” in the White academy and in tandem the bio-politics and bio-ethics of its right to be an affective body or to possess its senses against the trauma of anti-racist struggles in higher education institutions. The paper argues that in the postrace university, the “activist body” birthed through trauma becomes a conduit for the pain of others enacting it as a site for the deposition and transmutation of trauma in the quest for racial and social justice. It employs Bracha Ettinger’s notion of “matrixial borderspace” to examine the interplay of social relations between of the activist body and other traumatized subjects in the provision of care as an activist. Two narratives unfold in the paper fusing the articulations of the main text with the paratext to unleash the tumultuous psyche of the activist and her journey of voicing resistance in her anti-racist struggles. In the process, the activist body emerges as a “diseased site,” overloaded with the trauma of others, yet numbed in its inability to reconnect with its own corporeality and professional identity in its interface with White governmentality. The paper asserts that anti-racist struggles reassemble the activist body, tightly welding it with exhaustion which manifests in the pervasiveness of racial battle fatigue in the ivory tower.     

Using a Box–Cox transformation in the analysis of longitudinal data with incomplete responses

We analyse longitudinal data on CD4 cell counts from patients who participated in clinical trials that compared two therapeutic treatments: zidovudine and didanosine. The investigators were interested in modelling the CD4 cell count as a function of treatment, age at base-line and disease stage at base-line. Serious concerns can be raised about the normality assumption of CD4 cell counts that is implicit in many methods and therefore an analysis may have to start with a transformation. Instead of assuming that we know the transformation (e.g. logarithmic) that makes the outcome normal and linearly related to the covariates, we estimate the transformation, by using maximum likelihood, within the Box–Cox family. There has been considerable work on the Box–Cox transformation for univariate regression models. Here, we discuss the Box–Cox transformation for longitudinal regression models when the outcome can be missing over time, and we also implement a maximization method for the likelihood, assumming that the missing data are missing at random.     

A mathematical model and genetic algorithm-based approach for parallel two-sided assembly line balancing problem

Assembly lines are usually constructed as the last stage of the entire production system and efficiency of an assembly line is one of the most important factors which affect the performance of a complex production system. The main purpose of this paper is to mathematically formulate and to provide an insight for modelling the parallel two-sided assembly line balancing problem, where two or more two-sided assembly lines are constructed in parallel to each other. We also propose a new genetic algorithm (GA)-based approach in alternatively to the existing only solution approach in the literature, which is a tabu search algorithm. To the best of our knowledge, this is the first formal presentation of the problem as well as the proposed algorithm is the first attempt to solve the problem with a GA-based approach in the literature. The proposed approach is illustrated with an example to explain the procedures of the algorithm. Test problems are solved and promising results are obtained. Statistical tests are designed to analyse the advantage of line parallelisation in two-sided assembly lines through obtained test results. The response of the overall system to the changes in the cycle times of the parallel lines is also analysed through test problems for the first time in the literature.     

Effect of COVID-19 on Household Food Insecurity and Poverty: Evidence from Ghana

Social Indicators Research - Following the outbreak of COVID-19 and its heavy toll on the global community and humanity, a fierce debate on the pandemic and Sustainable Development Goals (SDGs)...     

FDA: strong consistency of the kNN local linear estimation of the functional conditional density and mode

In this paper we present a new estimator of the conditional density and mode when the co-variables are of functional kind. This estimator is a combination of both, the k-Nearest Neighbours procedure and the functional local linear estimation. Then, for each statistical parameter (conditional density or mode), results concerning the strong consistency and rate of convergence of the estimators are presented. Finally, their performances, for finite sample sizes, are illustrated by using simulated data.