Renal function assessment in adults with recurrent calcium kidney stone disease

The prevalence of nephrolihiasis and chronic kidney disease has risen over the past three decades, we sought to determine if person with a history of kidney stones have lower renal function relative to non stone formers. Methods: We conducted a case-control study utilizing 138 recurrent calcium kidney stone formers and 127 age and gender matched controls with no history of renal disease, all subjects were aged 30-55 years old, with no history of hypertension, diabetes mellitus, congestive heart failure and liver disease and also no urinary tract obstruction and medications can affect Glomerular Filtration Rate (GFR). We estimated GFR by Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease Epidemiology Collaboration (CKD-EP I) equations and categorized using cut points suggested by Kidney Disease Outcomes Quality Initiative (K/DOQI) guidelines. Results: Mean GFR in case group and control group was: 80.17(18.45) ml/min/1.73m2 and 83.80(15.75) ml/ min/1.73m2 respectively (P value: 0.09). Distribution of subjects among stone formers in stage I, II, III was 59(42.8%), 71(51.4%) and 8(5.8%) and in control group was 67(52.8%), 59(46.4%) and 1(0.8%) respectively, (p: 0.03). There was an inverse correlation between GFR and number of passed stone but there was no significant correlation between history of extracorporeal shock wave lithotripsy (ESWL) or percutaneous nephrolithotomy (PCNL) and estimated GFR. Conclusion: Recurrent calcium stone disease may be associated with nephron damage and an increased risk of chronic kidney disease

Impact of pressure fluctuations on pipe failures in water distribution networks

Water utilities operate ageing infrastructures that are degraded by environmental factors and operational stresses. Pipe failures have become a routine, resulting in major interruptions and extensive costs to the society. Pipe failure is a result of complex interactions between a variety of factors contributing to the pipe’s structural degradation and ultimate failure. Previous studies have extensively reviewed environmental and pipe-related factors. However, long term impact of quasi-steady and unsteady pressure variations on metallic pipe failures is not fully investigated. The overall aim of this project is to enhance the understanding of the dynamic pressure variations in water supply networks and evaluate their impact on pipe failures, with motivation to enhance the operational efficiency of water supply infrastructures by managing systems’ hydraulic conditions. In this study, a large-scale survey sampling programme is designed and executed in order to gather network representative high frequency pressure samples. A metric is formulated to quantify the stresses imposed on pipes from pressure variations. Causal analysis is undertaken and relationship between pipe failure and predictor variables are investigated by developing logistic regression models. The study develops a methodology for investigating cost-effectiveness of intervention measures and economic justification of the calm networks. The findings from the study illustrate positive associations between the system’s hydraulic variations and predicted probability of pipe failure. It is shown that deterioration models can be enhanced by including pressure variation characteristics as contributing factors to pipe degradation. Investment in achieving calm networks is demonstrated to be economically justifiable.Open Acces

Diffusion welding of nickel-based superalloys

Ni based superalloys can be welded by diffusion bonding. Temperature, diffusion coefficient, activation energy and Boltzmann constant influence the quality of diffusion bonding, so obtaining the best condition for welding is considered. Showing the suitable condition for diffusion welding of nickel-based superalloys is the aim of this paper

Evidence of Cheshmeh Ali Culture in Chenaran Plain (Northeastern Iran)

Despite the strategic position and specific economic conditions of Khorasan Province including location in the course of the route linking East to West and distinctive mineral resources no integrated study has been conducted to date for understanding the prehistoric cultures in this province Therefore archaeological excavations in Chenaran site as a major site in Mashhad Plain can elucidate the dark archeological aspects and chronological vacuum in this field Chenaran site is located on the northern margin of the current city of Chenaran in Khorasan Razavi Province It was excavated in the summer of 2012 The main objectives were to estimate the extent of the prehistoric site of Chenaran and present relative and absolute chronology from the lower layers to the end of settlement and fortunately considerable results in this field were achieved In this paper only the relative chronology results have been pointed and it is hoped that absolute chronology results are independently released in another article which is currently under consideration According to the pilot study and in a comparative approach with the settlements in southwestern Turkmenistan Chenaran site pottery is comparable with Anu Ia to Namazgah III perio

A Methodological View to the Works of Shiite Jurisprudence

In this research, with the aim of promoting the level of jurisprudential research and its more efficiency, comments and criticisms and suggestions presented in the field of methodology of famous legal works of regarding the issue of enjoining good and forbidding evil are detected and introduced. These criticisms include not paying attention to some important issues, despite development of too much of other issues, not finding new issue, and generalizations and not mentioning example

Class-Adaptive Sampling Policy for Efficient Continual Learning

Continual learning (CL) aims to acquire new knowledge while preserving information from previous experiences without forgetting. Though buffer-based methods (i.e., retaining samples from previous tasks) have achieved acceptable performance, determining how to allocate the buffer remains a critical challenge. Most recent research focuses on refining these methods but often fails to sufficiently consider the varying influence of samples on the learning process, and frequently overlooks the complexity of the classes/concepts being learned. Generally, these methods do not directly take into account the contribution of individual classes. However, our investigation indicates that more challenging classes necessitate preserving a larger number of samples compared to less challenging ones. To address this issue, we propose a novel method and policy named 'Class-Adaptive Sampling Policy' (CASP), which dynamically allocates storage space within the buffer. By utilizing concepts of class contribution and difficulty, CASP adaptively manages buffer space, allowing certain classes to occupy a larger portion of the buffer while reducing storage for others. This approach significantly improves the efficiency of knowledge retention and utilization. CASP provides a versatile solution to boost the performance and efficiency of CL. It meets the demand for dynamic buffer allocation, accommodating the varying contributions of different classes and their learning complexities over time