Investigating triple superphosphate for lead removal from aqueous solutions.

The aim of this research is to investigate monocalcium phosphate monohydrate [Ca(H2PO4)2. H2O] also called triple superphosphate (TSP) for the removal of lead (Pb) from aqueous solutions. In this study, TSP was selected amongst various phosphate-based materials and fertilizers to act as the source of orthophosphate (PO43-) which is a powerful tool for metal fixation in soil and water. Thermodynamic equilibrium dissolution-precipitation relationships for the systems of Pb-H2O and Pb-PO43--H2O were drawn with the aid of Eh-pH stability diagrams to determine the predominance areas of different species. The lead phosphate compounds, identified through the stability area diagrams, were verified with the batch precipitation tests performed with standard solutions of lead and TSP at different conditions. It was observed that, depending upon solution conditions, TSP can precipitate 99.9% of the lead from the solution. Lead precipitates, analyzed by x-ray diffraction, showed the formation of lead phosphate compounds. The mechanism of TSP for the removal of lead from aqueous solutions is discussed.

Assessing the knee flexion range of motion after total knee arthroplasty: Technology versus senses.

INTRODUCTION: Following total knee arthroplasty surgery, attention should be paid to post-operative knee range of motion to achieve daily activities. Goniometer assessment is widely used to assess the range of motion in the post-operative period. This study aimed to determine the inter-rater ability of a smartphone application and visual estimation of the knee joint after total knee arthroplasty among different professions that commonly work together and compare whether any method is superior to another. METHOD: Range of motion measurements was performed by four clinicians as two physiotherapists and two orthopedic fellows. They utilized the Goniometer Reports application for smartphones, universal goniometer, and visual estimation to measure angles of knees which was operated. A two-way mixed model of intra-class correlation coefficient (ICC) with a 95% confidence level was used to assess inter-rater reliability. RESULTS: Thirteen patients (11 female) and 20 knees (10 right) were assessed. The ICCs were found excellent both for between methods and between raters. CONCLUSION: Our results show that technology seems a more accurate way to determine the knee range of motion after knee arthroplasty compared to senses. However, in lack of technological resources or time, or to avoid possible infection, visual estimation also could provide useful information.

Iatrogenic lateral meniscus anterior horn injury in different tibial tunnel placement techniques in ACL reconstruction surgery - A cadaveric study.

OBJECTIVES: The aim of this study was to analyze the effect of tibial tunnel positioning in single bundle and double bundle ACL reconstructions on lateral meniscus anterior root. MATERIALS: Twelve single knee cadavers were used, 6 for a single bundle ACL reconstruction, which were reamed gradually starting from 8 mm, 9 mm and ended with a 10 mm reamers, while the other 6 were prepared for a double bundle ACL reconstruction in which 7 mm reamer for the AM tunnel and 6 mm reamer for the PL tunnel were used. After drilling, changes of lengths and thicknesses of anterior horns of the lateral menisci were recorded. RESULTS: Before drilling, the groups were homogenous for the lateral menisci dimensions. After drilling, no statistically significant difference was noticed between the two groups. However, in single bundle group, 2 anterior horns width injury (1.44 mm and 2.13 mm) with the 9 mm reamer and 3 anterior horns width injury (2.51 mm, 3.55 mm and 4.28 mm) with the 10 mm reamer were recorded. However in double bundle group a single anterior horn width injury (2.82 mm) was recorded. CONCLUSION: Using a greater size reamer in single bundle reconstruction, causes a relatively higher risk of lateral meniscal anterior root injury. Lateral meniscus stability should be examined arthroscopically after reaming with large reamers.

Measurement of regional trabecular bone attenuation of the knee following anterior cruciate ligament rupture.

INTRODUCTION: The purpose of this study was to determine regional trabecular bone attenuation changes of the knee using computed tomography after anterior cruciate ligament rupture. MATERIALS AND METHODS: Thirty one patients'-computed tomography images of the injured knees were used to measure trabecular bone attenuation in seven predetermined regions. RESULTS: Trabecular bone attenuation at four of seven regions (anteromedial area of the proximal tibia, anterolateral area of the proximal tibia, posteromedial area of the proximal tibia, and posterocentral area of the proximal tibia) was negatively correlated with the duration after injury. Independent negative correlation between the duration after injury and the density in anteromedial area of the proximal tibia was detected. CONCLUSIONS: After anterior cruciate ligament injury, trabecular bone attenuation of the knee decreases by time in certain regions of proximal tibia. Anteromedial region is the most significantly effected of all, which it is the anterior cruciate ligament fixation area.

The effects of blood transfusion on renal functions in orthopaedic surgery.

OBJECTIVE: The effects of perioperative blood transfusion on renal functions have been studied in various studies. In this study, we investigated the effects of blood transfusion on postoperative kidney functions in patients who underwent orthopaedic surgeries. METHOD: Total 136 patients who were operated for several orthopedic pathologies between June 2013 and December 2014 were evaluated. The patients were divided into two groups according to the amounts of blood transfusion. Ninety five patients (69.8%) who were transfused less than 3 units were included in Group 1 and 41 patients (30.2%) who received 3 and more units of blood were included in Group 2. RESULTS: There were no statistical difference between the two groups in terms of preoperative gender, hypertension, diabetes mellitus, chronical renal failure and smoking habbits (P > 0.05). No statistical differences between the groups were seen in terms of postoperative hospital stay, pulmonary and other complications as well as mortality (P > 0.05). When the two groups were compared for blood parameters showing postoperative renal and other system functions, no statistical differences were detected (P > 0.05). CONCLUSION: Blood transfusion does not have negative effects on postoperative BUN and creatinine levels in patients operated for orthopaedic pathologies.

Assessment of natural radioactivity in commercial granites used in Turkey.

The activity concentrations of (226)Ra, (232)Th and (40)K in twelve different domestic and imported tiling rocks (granites) used as building materials in Turkey were determined by employing high-resolution γ-ray spectrometry. The samples were evaluated to assess the radiation hazard for people by comparing the results with the control values recommended by the European Commission. The measured activity concentrations ranged from 7 to 136 Bq kg(-1), 9 to 138 Bq kg(-1) and 541 to 1277 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. Applying dose criteria recommended by the European Commission([15]), two of the samples showed higher Ra(eq) values than the limit dose of 370 Bq kg(-1), equivalent to a γ-dose of 1.5 mSv y(-1). The calculated gamma-index (I(γ)) values for all the 12 samples were lower than the recommended dose criterion. In some of the samples; however, the H(ex) and H(in) values were more than unity. The absorbed dose rates (D) for all the samples, except for four samples, were located within the range values recommended by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)([3]). Annual effective dose (AED) values, except for one sample, were greater than the world average value of UNSCEAR([3]).