Use of metallic fibers in concretes

The addition of a waste (fibers) in construction materials, particularly, the concretes is a technique increasingly used, for several reasons, either ecological, or economic, or to improve some properties in a fresh or hardened state. In our work we studied the behavior of the concrete and the mortar containing metallic fibers resulting from the unit BCR which is in Bordj-Menaiel in Algeria (metallic fibers resulting from the rejection at the end of the domestic operation of silvering of the tools and which is stored in plastic bags which are preserved in metal containers). Our work consists to study the behavior of the concretes and the mortars containing these fibers of cement substitution. We noted that the use of these fibers in the concretes in substitution of cement decreases its of compressive strength and flexural strength but to 10% of waste these strength remain acceptable

Study of the mechanical characteristics and chemical degradation of concretes based on machining sludge

The main objective of this work is to study the mechanical characteristics and the chemical degradation of mortars and concretes made obtained by substituting the cement by the machining sludge. Several materials were carried out by substituting the cement with different amount of machining sludge (5, 10, 15 and 20%). The obtained materials are compared to those without substitution (ie: 00wt% of machining sludge). Mechanical and physical properties of the two materials (mortars and concretes) as flexural and compressive strengths were studied. Physical properties as shrinkage, the bloating effect, loss in mass, slump concretes and porosity were evaluated. In addition, chemical degradation is studied for the conservation of these concretes and mortars from machining sludge in different aggressive environment. Moreover, the addition of 5wt% of the machining sludge in the mixture of the mortar and the concretes seems to be interesting

Study of the mechanical characteristics and chemical degradation of concretes based on machining sludge

The main objective of this work is to study the mechanical characteristics and the chemical degradation of mortars and concretes made obtained by substituting the cement by the machining sludge. Several materials were carried out by substituting the cement with different amount of machining sludge (5, 10, 15 and 20%). The obtained materials are compared to those without substitution (ie: 00wt% of machining sludge). Mechanical and physical properties of the two materials (mortars and concretes) as flexural and compressive strengths were studied. Physical properties as shrinkage, the bloating effect, loss in mass, slump concretes and porosity were evaluated. In addition, chemical degradation is studied for the conservation of these concretes and mortars from machining sludge in different aggressive environment. Moreover, the addition of 5wt% of the machining sludge in the mixture of the mortar and the concretes seems to be interesting

Outcome ketamine infusions: is there a difference between 1 and 3-day infusions?

Introduction: Chronic pain impacts many aspects of a patient’s quality of life (QOL). Ketamine is a NMDA receptor antagonist that has been used for neuropathic pain. This study aims to: (1) evaluate the impact of outpatient ketamine infusions on pain and QOL with a larger sample size than our previous study; (2) determine if there is a difference in results in patients receiving 1 or 3-day infusions; and, (3) examine whether repeated infusions have an influence on outcomes. Methods: With IRB approval, 118 patients completed the basic pain inventory (BPI) to rate, on a scale from 0 to 10, their pain and the degree pain interfered with QOL (general activity, walking, work, relationships, mood, sleep, and enjoyment of life). The BPI was completed prior to 1 or 3-day infusions and was repeated 2-4 weeks after infusions. Paired two tailed t-tests and random effect mixed models were used to compare post and pre-infusion scores. Results: There was statistically significant improvement (p\u3c0.05) in pain, enjoyment of life, general activity, mood, work, relationships, and sleep, but not walking (p= 0.2419). There was no significant difference in outcomes between 1 and 3-day infusions. However, this may be overstated, as there was a small sample of 1-day infusions. Repeaters had significant cumulative improvement in enjoyment of life (p= 0.0132) and relationships (p= 0.0092) with increased number of repeated infusions. Conclusion: 1 and 3-day outpatient ketamine infusions improve pain levels and QOL and may provide cumulative benefits with repeated infusions in patients with chronic neuropathic pain. References Collins, S., et al. NMDA receptor antagonists for the treatment of neuropathic pain. Pain Med, 2010. 11(11): p. 1726-42. Niesters, M., C. Martini, and A. Dahan. Ketamine for chronic pain: risks and benefits. Br J Clin Pharmacol, 2014. 77 (2): p. 357-67. Introduction: Chronic pain impacts many aspects of a patient’s quality of life (QOL). Ketamine is a NMDA receptor antagonist that has been used for neuropathic pain. This study aims to: (1) evaluate the impact of outpatient ketamine infusions on pain and QOL with a larger sample size than our previous study; (2) determine if there is a difference in results in patients receiving 1 or 3-day infusions; and, (3) examine whether repeated infusions have an influence on outcomes. Methods: With IRB approval, 118 patients completed the basic pain inventory (BPI) to rate, on a scale from 0 to 10, their pain and the degree pain interfered with QOL (general activity, walking, work, relationships, mood, sleep, and enjoyment of life). The BPI was completed prior to 1 or 3-day infusions and was repeated 2-4 weeks after infusions. Paired two tailed t-tests and random effect mixed models were used to compare post and pre-infusion scores. Results: There was statistically significant improvement (p\u3c0.05) in pain, enjoyment of life, general activity, mood, work, relationships, and sleep, but not walking (p= 0.2419). There was no significant difference in outcomes between 1 and 3-day infusions. However, this may be overstated, as there was a small sample of 1-day infusions. Repeaters had significant cumulative improvement in enjoyment of life (p= 0.0132) and relationships (p= 0.0092) with increased number of repeated infusions. Conclusion: 1 and 3-day outpatient ketamine infusions improve pain levels and QOL and may provide cumulative benefits with repeated infusions in patients with chronic neuropathic pain. References Collins, S., et al. NMDA receptor antagonists for the treatment of neuropathic pain. Pain Med, 2010. 11(11): p. 1726-42. Niesters, M., C. Martini, and A. Dahan. Ketamine for chronic pain: risks and benefits. Br J Clin Pharmacol, 2014. 77 (2): p. 357-67