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The exponential growth in demand for housing has resulted in a greater focus on rapid construction methods that adhere to circular economy principles. 3D concrete printing is becoming a powerful tool to find solutions to the common challenges of affordable housing for more people, rapid construction, and the digitalization of the construction industry. However, a coherent synthesis of green and digital initiatives has not yet been achieved. For 3D printable materials, recycling of materials that have reached the end of their service life should also be enabled and supported, in line with circular economy goals that prioritize waste reduction and maximization of resource efficiency. With these objectives in mind, the current study focuses on the development of a one-part 3D printable alkali-activated mortar (3DPM) derived from brick masonry waste (BMW). BMWs were used as the main precursor and filler phase, whereas materials such as ground granulated blast furnace slag, kaolin clay, and limestone have been utilized to enhance/control the mechanical and rheological properties. To investigate the evolution of alkali-activation and the effect of anisotropy, the macromechanical properties of the developed 3DPM were investigated by compressive strength, flexural strength, split tensile, and direct tensile tests. The micromechanical properties were analyzed using X-ray fluorescence spectrometry (XRF), X-ray diffraction (XRD), Fourier transform infrared (FTIR), thermogravimetry (TG), differential scanning calorimetry (DSC), scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM/EDX), and computed tomography (MicroCT) tests. Overall, the results revealed the presence of anisotropy, which can be reduced by optimizing the layer height. Through this optimization, reductions in pore content and distribution, validated by MicroCT, indicated that the disadvantage of the weak interlayer bond zone in stress transfer could be diminished. Micromechanical analysis showed that the gel formation responsible for the strength was the calcium-based gel structures. Considering these findings, it is believed that the BMW-based 3DPM can be an important alternative for the digitalization of the construction industry and its transition to a circular economy.

Study Objective: Erector spinae plane (ESP) block is a novel regional anesthesia technique and gaining importance for postoperative pain management. Since it was first described, the clinicians wonder if this new simple technique can replace paravertebral block (PVB). We aimed to compare the postoperative analgesic effect of ESP block and PVB with a control group in breast surgeries., Design: Randomized controlled trial., Setting: Operating room., Patients: Seventy-five ASA I-II patients aged 25-65, who were scheduled to go under elective unilateral breast surgery for breast cancer were included to the study., Interventions: Patients were randomized into three groups as ESP, PVB, and Control group. Ultrasound (US) guided ESP block and PVB with 20 ml 0.25% bupivacaine was done preoperatively to the patients according to their groups., Measurements: All patients were provided with iv patient-controlled analgesia device for postoperative analgesia. Morphine consumptions and numeric rating scale (NRS) scores for pain were recorded at 1st, 6th, 12th and 24th hours postoperatively., Main Results: There was a statistically significant difference between ESP and Control groups (p < 0,001) and between PVB and Control groups (p < 0,001), while there was no difference between ESP and PVB groups (p > 0,05) for 24-hour morphine consumptions. There was a significant difference between PVB and Control groups for NRS at postoperative 1st and 6th hour (p = 0.018 and p = 0.027 respectively)., Conclusions: This study has shown that US guided ESP block and PVB provided adequate analgesia in patients undergoing breast surgery and have an opioid sparing effect by reducing morphine consumption. Clinical Trials Registry: NCT03480958., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Study Objective: To evaluate and compare the analgesic effect of ultrasound-guided erector spinae plane (ESP) block with ultrasound-guided Quadratus Lumborum Block in pediatric lower abdominal surgeries., Design: Randomized, prospective, double-blinded trial., Setting: Operating room and surgical ward., Patients: Sixty patients, aged 1 to 7 years with ASA scores of I-II scheduled for elective lower abdominal surgery were included in the study., Interventions: Patients were randomized into two groups as ESPB group and QLB group. Ultrasound guided ESP block at L1 vertebral level was performed preoperatively using 0.5 ml/kg 0.25% bupivacaine (max 20 ml) to the patients in ESPB group. And ultrasound guided QLB block with transmuscular approach was performed preoperatively using 0.5 ml/kg 0.25% bupivacaine (max 20 ml) to the patients in QLB group., Measurements: Face, Legs, Activity, Cry and Consolability (FLACC) scores for pain were recorded at 0, 1, 3 and 6 h postoperatively. Analgesic requirements and time to first analgesic requirement were also recorded., Main Results: Fifty-seven patients were included in the final analyses. No significant difference was determined between the groups' FLACC scores at 0, 1, 3 or 6 h postoperatively (p > 0.05). No significant difference was also determined in times to first analgesia between the groups (p > 0.05)., Conclusions: This study shows that the ESPB provides similar postoperative analgesia to the QLB in pediatric patients undergoing lower abdominal surgery. Clinicians could decide according to their clinical experiences. CLINICAL TRIALS: https://clinicaltrials.gov/ct2/show/NCT03463382., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Study Objective: To evaluate the analgesic effect of ultrasound-guided erector spinae plane (ESP) block in breast cancer surgery., Design: Randomized controlled, single-blinded trial., Setting: Operating room., Patients: Fifty ASA I-II patients aged 25-65 and scheduled for elective breast cancer surgery were included in the study., Interventions: Patients were randomized into two groups, ESP and control. Single-shot ultrasound (US)-guided ESP block with 20 ml 0.25% bupivacaine at the T4 vertebral level was performed preoperatively to all patients in the ESP group. The control group received no intervention. Patients in both groups were provided with intravenous patient-controlled analgesia device containing morphine for postoperative analgesia., Measurements: Morphine consumption and numeric rating scale (NRS) pain scores were recorded at 1, 6, 12 and 24 h postoperatively., Main Results: Morphine consumption at postoperative hours 1, 6, 12 and 24 decreased significantly in the ESP group (p < 0.05 for each time interval). Total morphine consumption decreased by 65% at 24 h compared to the control group (5.76 ± 3.8 mg vs 16.6 ± 6.92 mg). There was no statistically significant difference between the groups in terms of NRS scores., Conclusions: Our study findings show that US-guided ESP block exhibits a significant analgesic effect in patients undergoing breast cancer surgery. Further studies comparing different regional anesthesia techniques are needed to identify the optimal analgesia technique for this group of patients., (Copyright © 2018 Elsevier Inc. All rights reserved.)