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Chlorine and fluorine substituted hydroxyapatites (HA-Cl-F) with different degrees of ion replacement were successfully prepared by the one step mechanochemical activation method. X-ray diffraction (XRD) and FT-IR spectra indicated that substitution of these anions in milled powders resulted in the formation of pure hydroxyapatite phase except for the small observed change in the lattice parameters and unit cell volumes of the resultant hydroxyapatite. Microscopic observations showed that the milled product had a cluster-like structure made up of polygonal and spherical particles with an average particle size of approximately ranged from 20±5 to 70±5nm. The zeta potential of milled samples was performed at three different pH (5, 7.4, and 9). The obtained zeta potential values were negative for all three pH values. Negative zeta potential was described to favor osseointegration, apatite nucleation, and bone regeneration. The bioactivity of samples was investigated on sintered pellets soaked in simulated body fluid (SBF) solution and apatite crystals formed on the surface of the pellets after being incubated for 14days. Zeta potential analysis and bioactivity experiment suggested that HA-Cl-F will lead to the formation of new apatite particles and therefore be a potential implant material., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Objective: We assessed the validity of the Center for Epidemiological Studies Depression Scale for Children (CES-DC) as a screen for depression in Rwandan children and adolescents. Although the CES-DC is widely used for depression screening in high-income countries, its validity in low-income and culturally diverse settings, including sub-Saharan Africa, is unknown., Method: The CES-DC was selected based on alignment with local expressions of depression-like problems in Rwandan children and adolescents. To examine criterion validity, we compared CES-DC scores to depression diagnoses on a structured diagnostic interview, the Mini International Neuropsychiatric Interview for Children (MINI KID), in a sample of 367 Rwandan children and adolescents aged 10 through 17 years. Caregiver and child or adolescent self-reports endorsing the presence of local depression-like problems agahinda kenshi (persistent sorrow) and kwiheba (severe hopelessness) were also examined for agreement with MINI KID diagnosis., Results: The CES-DC exhibited good internal reliability (α = .86) and test-retest reliability (r = .85). The area under the receiver operating characteristic curve for the CES-DC was 0.825 when compared to MINI KID diagnoses, indicating a strong ability to distinguish between depressed and nondepressed children and adolescents in Rwanda. A cut point of≥30 corresponded with a sensitivity of 81.9% and a specificity of 71.9% in this referred sample. MINI KID diagnosis was well aligned with local expressions of depression-like problems., Conclusion: The CES-DC demonstrates good psychometric properties for clinical screening and evaluation in Rwanda, and should be considered for use in this and other low-resource settings. Population samples are needed to determine a generalizable cut point in nonreferred samples., (Copyright © 2012 American Academy of Child and Adolescent Psychiatry. Published by Elsevier Inc. All rights reserved.)