Optimization of eco-friendly concrete with recycled coarse aggregates and rubber particles as sustainable industrial byproducts for construction practices

In this technology era, sustainable construction practices have become quite imperative. The exploration of alternative materials to reduce the environmental footprint is of paramount importance. This research paper delves into an exhaustive investigation concerning the utilization of recycled coarse aggregates (RCA) and rubber particles (RP) in concrete. It contributes to the growing body of knowledge aimed at fostering sustainable development in the construction industry by reducing waste, promoting recycling, and mitigating the environmental footprint of building materials. The objective of the study is to evaluate the potential benefits and limitations associated with incorporating these materials, thereby providing a sustainable alternative to conventional concrete. In this research, construction and demolition waste were recycled and used as RCA as a fractional switch of natural coarse aggregate (NCA) from 0% to 100%, with an increment of 20% replacement of NCA in concrete. The RP received from discarded tires generated as automobile industry waste were used as a volumetric fractional substitution of sand in concrete from 0% to 20%, with a 5% increment. No pre-treatment for RCA and RP was carried out before their utilization in concrete. A total of 26 mixes, including control concrete without NCA and RP, with a design strength of 40 MPa, were prepared and tested. Concrete mixes were examined for workability, density, mechanical, and durability properties. It was found that the concrete with 60% RCA and 10% RP showed satisfactory results in evaluation with the strength parameters of control concrete, as the compressive strength obtained for this concrete mix is 40.18 MPa, similar to the control mix. The optimization for RCA and RP was conducted using Response Surface Methodology (RSM). The major concern observed was a rise in water absorption with an increase in the percentage replacement of NCA and natural sand by RCA and RP. Findings from the investigation illustrate a promising prospect for the use of RCA and RP in concrete applications, displaying competent mechanical properties and enhanced durability under certain conditions, offering a viable option for environmentally friendly construction practices. However, the research also sheds light on some constraints and challenges, such as the variability in the quality of RCA and the necessity for meticulous quality control to ensure the reliability and consistency of the end product. It is discerned that further refinement in processing techniques and quality assurance measures is pivotal for mainstream adoption of RCA and RP in concrete construction.

Orthotopic bladder substitution: Surgical aspects and optimization of outcomes

Objectives

Orthotopic bladder substitution (OBS) is a management option for urinary diversion in men and women undergoing cystectomy. The aim of the procedure is to provide a functional continent urinary reservoir of adequate capacity, compliance and low pressure. We have provided a narrative review of the existing literature and highlighted areas where improvement and standardization can be recommended.

Methods

Literature search included database search for publications from January 1970 to November 2020, using keywords including OBS, bladder reconstruction, neobladder, radical cystectomy, robotic cystectomy, intracorporeal neobladder, surgical technique, patient selection and outcomes.

Results

Due to various factors including indications, operative technique and risk of complications, OBS is an enormous undertaking and commitment for patients, surgeons and health professionals involved in the care pathway. The main considerations for patient selection, the technical elements of the procedure and the rationale behind these are discussed. Previously considered to be a choice for a select few, the inclusion criteria have expanded over the last decade. Similarly, surgical techniques including the choice and configuration of bowel segments, construction of anastomosis and nerve or organ sparing procedures have evolved over the years. Minimally invasive laparoscopic and robotic assisted surgery has added further perspectives to the existing literature on OBS. Understanding the principles of operative techniques and assessing the best evidence to influence patient management is crucial as it has a major impact on clinical outcomes. Peri‐ and post‐operative care, focused on the prevention of complications and morbidity, affects long‐term functional and oncological outcomes, which ultimately dictates the quality of life.

Conclusions

This concise overview of OBS literature highlights the importance of pre‐operative, peri‐operative, and post‐operative aspects with regards to the optimization of patient care. To achieve the best results, meticulous attention should be paid in all these areas, surgical and multi‐disciplinary. Patient education and counseling, with shared decision making are central to the success of the procedure.

Efficacy and safety of the EMS Swiss LithoClast® Trilogy for PCNL: results of the European multicentre prospective study on behalf of European Section of UroTechnology

Purpose

PCNL requires a lithotrite to efficiently break stones, and some devices include active suction to remove the fragments. We set out to determine the efficacy and safety of the Swiss LithoClast® Trilogy, in a prospective European multicentre evaluation and compared it to published stone clearance rates for Trilogy based on surface area (68.9 mm²/min) and using the 3D calculated stone volume (526.7 mm³/min).

Methods

Ten European centres participated in this prospective non-randomized study of Trilogy for PCNL. Objective measures of stone clearance rate, device malfunction, complications and stone-free rates were assessed. Each surgeon subjectively evaluated ergonomic and device effectiveness, on a 1–10 scale (10 = extremely ergonomic/effective) and compared to their usual lithotrite on a 1–10 scale (10 = extremely effective).

Results

One hundred and fifty seven PCNLs using Trilogy were included (53% male, 47% female; mean age 55 years, range 13–84 years). Mean stone clearance rate was 65.55 mm²/min or 945 mm³/min based on calculated 3D volume. Stone-free rate on fluoroscopy screening at the end of the procedure was 83%. Feedback for suction effectiveness was 9.0 with 9.1 for combination and 9.0 for overall effectiveness compared to lithotrite used previously. Ergonomic score was 8.1, the least satisfactory element. Complications included 13 (8.2%) Clavien–Dindo Grade II and 2 (1.3%) Grade III. Probe breakage was seen in 9 (5.7%), none required using a different lithotrite.

Conclusions

We have demonstrated that Trilogy is highly effective at stone removal. From a user perspective, the device was perceived by surgeons to be highly effective overall and compared to the most commonly used previous lithotrite, with an excellent safety profile.