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Severe hematopoietic loss is one of the major therapeutic targets after radiation-combined injury (CI), a kind of injury resulting from radiation exposure combined with other traumas. In this study, we tested the use of ciprofloxacin (CIP) as a treatment, because of recently reported immunomodulatory effects against CI that may improve hematopoiesis. The CIP regimen was a daily, oral dose for 3 weeks, with the first dose 2 h after CI. CIP treatment improved 30-day survival in mice at 80% compared to 35% for untreated controls. Study of early changes in hematological parameters identified CI-induced progressive anemia by 10 days that CIP significantly ameliorated. CI induced erythropoietin (EPO) mRNA in kidney and protein in kidney and serum; CIP stimulated EPO mRNA expression. In spleens of CI mice, CIP induced bone morphogenetic protein 4 (BMP4) in macrophages with EPO receptors. Splenocytes from CIP-treated CI mice formed CD71⁺ colony-forming unit-erythroid significantly better than those from controls. Thus, CIP-mediated BMP4-dependent stress erythropoiesis may play a role in improving survival after CI.

A novel solid-state neutron and gamma radiation monitor-dosimeter based on biopolymer polylactic acid (PLA) is presented. The resulting detector (PLAD) technology takes advantage of property changes of the renewable PLA resin when subject to ionizing nuclear radiation. A simple yet rapid and accurate (±10%) low-cost (TM Co-60 irradiator, and the PUR-1 12 kW fission nuclear research reactor were utilized, respectively. Irradiation absorbed doses ranged from 1 to 100 kGy. Acetone bath temperature was varied from ~40 °C to ~54 °C. Results revealed a strong dependence of MLD on acetone bath temperature between neutron and gamma photon dose components; this allowed for the unique ability of PLAD to potentially perform as both a neutron-cum-gamma or as a gamma or neutron radiation dosimeter and intensity level detector. A linear trend is found for combined neutron and gamma radiation doses from 0 to 40 kGy when dissolution is conducted above 50 °C. The important potential ability to distinguish neutron from gamma radiation fields was scoped and found to be feasible by determining MLD at 45 °C. The potential was studied for simultaneous use as an in-core neutron and gamma monitor of an operating 3 GWt light-water reactor (LWR). Scoping tests were conducted with the pre-irradiated (@ 20 °C) PLAD resin beads followed by heating to in-core LWR coolant (300 °C) conditions for ~30 s corresponding to the time to reach ~40 kGy total doses in a typical 3 GWt LWR. MLD results were unaffected, indicating the exciting and unique potential for in situ (low-cost, accurate and rapid) simultaneous mapping of neutron and gamma radiation fluxes, related dosimetry, and fission power level monitoring.

This study of mothers and infants from the Dogon ethnic group of Mali, West Africa examined three attachment hypotheses: (1) that infant attachment security is linked to the quality of mother-infant communication, (2) that mothers of secure infants respond more sensitively to their infants than do mothers of insecure infants, and (3) that infant disorganization is linked to maternal frightened or frightening behaviors. Participants were 27 mother-infant pairs from a rural town and 15 mother-infant pairs from two agrarian villages; infants ranged in age from 10 to 12.5 months at the first assessment. The distribution of the Strange Situation classifications was 67% secure, 0% avoidant, 8% resistant, and 25% disorganized. Infant attachment security was significantly related to the quality of mother-infant communication as observed in a well-infant exam. The correlation between infant attachment security ratings and maternal sensitivity (assessed in the home) was modest and approached significance. Mothers of disorganized infants had significantly higher ratings of frightened or frightening behaviors. Maternal sensitivity predicted little of the variance in infant security; however, the addition of the frightened/frightening variable in the regression equation tripled the explained variance. The findings are discussed in light of Dogon childrearing practices and key tenets of attachment theory. [ABSTRACT FROM AUTHOR]

The Weibel instability is caused by anisotropy in the velocity distribution. In the collisionless spherical corona of a laser fusion target, anisotropy in electron velocity space is naturally produced by a localized source because angular momentum, l = mυ[sub ⊥] r, is conserved and the perpendicular energy, E[sub ⊥] = l²/2mr², decreases at radii large compared to the source radius. This occurs even if the source is locally isotropic (e.g., inverse bremsstrahlung around the critical density). Linear growth rates are computed for the Weibel instability with a model distribution that includes the aforementioned effects as well as diffusion in angular momentum and energy loss by hydrodynamic expansion. [ABSTRACT FROM AUTHOR]