Understanding Health Risks for Adolescents in Protective Custody

Children in child welfare protective custody (e.g., foster care) are known to have increased health concerns compared to children not in protective custody. The poor health documented for children in protective custody persists well into adulthood; young adults who emancipate from protective custody report poorer health, lower quality of life, and increased health risk behaviors compared to young adults in the general population. This includes increased mental health concerns, substance use, sexually transmitted infections, unintended pregnancy, and HIV diagnosis. Identifying youth in protective custody with mental health concerns, chronic medical conditions, and increased health risk behaviors while they remain in custody would provide the opportunity to target prevention and intervention efforts to curtail poor health outcomes while youth are still connected to health and social services. This study leveraged linked electronic health records and child welfare administrative records for 351 youth ages 15 and older to identify young people in custody who were experiencing mental health conditions, chronic medical conditions, and health risk behaviors (e.g., substance use, sexual risk). Results indicate that 41.6% of youth have a mental health diagnosis, with depression and behavior disorders most common. Additionally, 41.3% of youth experience chronic medical conditions, primarily allergies, obesity, and vision and hearing concerns. Finally, 39.6% of youth use substances and 37.0% engage in risky sexual behaviors. Predictors of health risks were examined. Those findings indicate that women, those with longer lengths of stay and more times in custody, and those in independent living and conjugate care settings are at greatest risk for mental health conditions, chronic medical conditions, and health risk behaviors. Results suggest a need to ensure that youth remain connected to health and mental health safety nets, with particular attention needed for adolescents in care for longer and/or those placed in non-family style settings. Understanding who is at risk is critical for developing interventions and policies to target youth who are most vulnerable for increased health concerns that can be implemented while they are in custody and are available to receive services

Excitonic fine structure and recombination dynamics in single-crystalline ZnO

The optical properties of a high quality bulk ZnO, thermally post treated in a forming gas environment are investigated by temperature dependent continuous wave and time-resolved photoluminescence (PL) measurements. Several bound and free exciton transitions along with their first excited states have been observed at low temperatures, with the main neutral-donor-bound exciton peak at 3.3605 eV having a linewidth of 0.7 meV and dominating the PL spectrum at 10 K. This bound exciton transition was visible only below 150 K, whereas the A-free exciton transition at 3.3771 eV persisted up to room temperature. A-free exciton binding energy of 60 meV is obtained from the position of the excited states of the free excitons. Additional intrinsic and extrinsic fine structures such as polariton, two-electron satellites, donor-acceptor pair transitions, and longitudinal optical-phonon replicas have also been observed and investigated in detail. Time-resolved PL measurements at room temperature reveal a biexponential decay behavior with typical decay constants of similar to170 and similar to864 ps for the as-grown sample. Thermal treatment is observed to increase the carrier lifetimes when performed in a forming gas environment

Comparative study of the (0001) and (0001) surfaces of ZnO

The authors compare the surface and optical properties of the Zn-polar (0001) and O-polar (0001¯)surfaces of bulk ZnO samples. For optical characterization, steady-state photoluminescence using a He–Cd laser was measured at 15 and 300K. At room temperature, the (0001¯)surface demonstrates nearly double the near-band-edge emission intensity seen for the (0001) surface. Using scanning Kelvin probe microscopy, the authors have measured surface contact potentials of 0.39±0.05 and 0.50±0.05V for the (0001) and (0001¯)surfaces, respectively. The resulting small difference in band bending for these two surfaces indicates that charge transfer between the surfaces is not a dominant stabilizing mechanism. Conductive atomic force microscopy studies show enhanced reverse-bias conduction in localized regions on the (0001¯) vs (0001) surface. The differences in surface conduction and band bending between the two polar surfaces can be attributed to their chemical interactions with hydrogen and water in the ambient

Sensory properties of probiotic yogurt is comparable to standard yogurt

Thirty ureteral stents, inserted for 5 to 128 days following extracorporeal shock wave lithotripsy, were examined for the presence of bacterial biofilms. Of these, 90% had adherent pathogens (44% mixed organisms) on the stents, 45% of which were present in low numbers (10 -10 per 1 cm section) and 55% were in small and large microcolony biofilms (\u3e2 x 10 -10 ). The organisms were recovered from the stents even though urine culture was only positive in 27% of patients. Of the organisms isolated, 77% were Gram positive cocci, 15% Gram negative rods and 8% Candida. No blockage of the stents occurred. All of the patients had received antimicrobial therapy post-insertion, and in 15 cases biofilms were found while on treatment. None of the patients received therapy for urinary tract infections while the stent remained in place. In vitro experiments demonstrated the ability of Escherichia coli, Proteus mirabilis, Staphylococcus epidermidis and Enterococcus faecalis uropathogens to adhere and form biofilms on ureteral stents within 24 hours. Clearly, bacterial biofilms do occur on ureteral stents and urinary culture may not detect their presence. The high recovery rate of Gram positive organisms may indicate a preferential adhesion to the biomaterial surface. The findings also indicate that unlike biofilm formation on many other prosthetic implants, colonization with Gram positive organisms on ureteral stents does not necessarily coincide with the development symptomatic infection. 1 2 3 2

Magnetic properties of bulk Zn₁₋ₓMnₓO and Zn₁₋ₓCoₓO single crystals

© 2004 American Institute of Physics. The electronic version of this article is the complete one and can be found at: http://dx.doi.org/10.1063/1.1830084DOI: 10.1063/1.1830084Manganese and cobalt-doped ZnO have been produced using a modified melt-growth technique. X-ray diffraction measurements indicate that the samples are high-quality single crystals with ω−2θ full width at half maximum values of 78 arc sec for the undoped ZnO and 252 arc sec for Zn₁₋ₓMnₓO (x = 0.05). The lattice parameter of the Zn₁₋ₓMnₓO was observed to increase with Mn concentration. Transmission measurements showed systematic variations dominated by absorption from interatomic Mn²⁺ and Co²⁺ transitions. No evidence of diluted magnetic semiconductor mean-field ferromagnetic behavior was observed in any of these nominally noncarrier-doped samples. The magnetic properties instead showed paramagnetic behavior for Zn₁₋ₓMnₓO dominated by an antiferromagnetic Mn–Mn exchange interaction at low temperatures. Zn ₁₋ₓ CoₓO showed hysteresis that was attributed to superparamagnetic Co clusters embedded in a diamagnetic ZnO matrix. It has been shown that in the bulk single-crystal form, intrinsic and noncarrier-doped Zn₁₋ₓTMₓO is not ferromagnetic; thus creative processing and doping techniques are necessary to achieve practical ferromagnetism in these materials