We conducted a systematic review to examine the relationship between intracranial pressure monitors (ICP) monitors and mortality in traumatic brain injury (TBI). We systematically searched for articles that met the following criteria: (1) adults patients, (2) TBI, (3) use of an ICP monitor, (4) point estimate for mortality with ICP monitoring (5) adjustment for potential confounders. Six observational studies were identified with 11,371 patients. There was marked between-study heterogeneity that precluded a pooled analysis. Patients with ICP monitors had different clinical characteristics and received more ICP targeted therapy in the ICU. Four studies found no significant relationship between ICP monitoring and survival, while the other two studies demonstrated conflicting results. Significant confounding by indication in observational studies limits the examination of isolated TBI interventions. More research should focus on interventions that affect TBI careplan systems. Further research is needed to identify which subset of severe TBI patients may benefit from ICP monitoring.

Many U.S. Gulf War-era veterans complained of poor cognition following the war. This study assessed neuropsychological functioning in veterans 10 years after the war through objective tests. 2189 Gulf War-era veterans (1061 deployed, 1128 non-deployed) were examined at 1 of 16 U.S. Veterans Affairs medical centers. Outcomes included neuropsychological domains derived from factor analysis and individual test scores. Deployed veterans performed significantly worse than non-deployed veterans on 2 of 8 factors (motor speed & sustained attention, analysis not corrected for multiple comparisons) and on 4 of 27 individual test variables (Trails A & B, California Verbal Learning Test – List B, and Continuous Performance Test sensitivity, with only Trails B surviving Bonferroni correction). Within deployed veterans, Khamisiyah exposure was negatively correlated with motor speed after controlling for emotional distress. Depressive symptoms and self-reported exposure to toxicants were independently and significantly associated with worse sustained attention. Other factors were also associated with self-reported exposures. The findings were not a result of differential effort across groups. Gulf War deployment is associated with subtle declines of motor speed and sustained attention, despite overall intact neuropsychological functioning. Evidence suggests that toxicant exposures influence both these functions, and depressive symptoms also influence attention. (JINS, 2009, 15, 717–729.)

Simulation-based policy iteration (SBPI) is a modification of the policy iteration algorithm for computing optimal policies for Markov decision processes. At each iteration, rather than solving the average evaluation equations, SBPI employs simulation to estimate a solution to these equations. For recurrent average-reward Markov decision processes with finite state and action spaces, we provide easily verifiable conditions that ensure that simulation-based policy iteration almost-surely eventually never leaves the set of optimal decision rules. We analyze three simulation estimators for solutions to the average evaluation equations. Using our general results, we derive simple conditions on the simulation run lengths that guarantee the almost-sure convergence of the algorithm.

The Vietnam Era Twin (VET) Registry is composed of 7369 middle-aged male-male twin pairs both of whom served in the military during the time of the Vietnam conflict (1965–1975). The Registry is a United States Department of Veterans Affairs resource that was originally constructed from military records; the Registry has been in existence for more than 15 years. It is one of the largest national twin registries in the US and currently has subjects living in all 50 states. Initially formed to address questions about the long-term health effects of service in Vietnam the Registry has evolved into a resource for genetic epidemiologic studies of mental and physical health conditions. The management and administration of the VET Registry is described with particular attention given to the processes involved with database maintenance and study coordination. Several waves of mail and telephone surveys have collected a wealth of health-related information on Registry twins. More recent data collection efforts have focused on specific sets of twin pairs and conducted detailed clinical or laboratory testing. New Registry initiatives for the future include the construction of a web site and the development of a DNA repository.

Key features of reproductive behavior in China vary systematically through space and time. In this article we present an analysis of fertility change in regional space, using a 1% household sample from China’s 1990 population census. Elsewhere,we use the same data to analyze reproductive strategizing, but here we pursue the big picture with a straightforward analysis that takes reported births as an uncomplicated indicator of fertility.The article has three objectives: first, to introduce a novel, multilevel spatial model of regional structure constructed using a geographic information system (GIS); second, to demonstrate the potential for longitudinal data derived from onetime censuses to contribute to historical demography in conjunction with regional analysis; and third, to document the manner in which China’s fertility transition has unfolded in regional space.

Excavations at two sites in Gwynedd have produced new evidence for highland zone rural settlement during the Romano-British period. At Bryn Eryr this activity was the culmination of a long sequence of development during the Iron Age. At Bush Farm, similarly, a Romano-British phase succeeded earlier, probably late prehistoric occupation of the site. At both locations significant structural changes took place during the Romano-British period as small stone-walled houses replaced larger, clay-walled buildings. Changes in the local farming economy have been identified and the proximity of the vicus at Segontium provided access to Roman pottery vessels. The quality and range of pottery from Bryn Eryr and Bush Farm are considerable in comparison with other ‘Highland Zone’ settlements and the material is discussed in detail.

Radiation effects in nonmetals have been studied for well over a century by geologists, mineralogists, physicists, and materials scientists. The present work focuses on recent results of investigations of the ion-beam-induced amorphization of the ABO4 compounds – including the orthophosphates (LnPO4; Ln = lanthanides) and the orthosilicates: zircon (ZrSiO4), hafnon (HfSiO4), and thorite (ThSiO4). In the case of the orthosilicates, heavy-ion irradiation at elevated temperatures causes the precipitation of a nanocrystalline metal oxide. Electron irradiation effects in these amorphized insulating ceramics can produce localized recrystallization on a nanometer scale. Similar electron irradiation techniques were used to nucleate monodispersed compound semiconductor nanocrystals formed by ion implantation of the elemental components into fused silica. Methods for the formation of novel structural relationships between embedded nanocrystals and their hosts have been developed and the results presented here demonstrate the general flexibility of ion implantation and irradiation techniques for producing unique near-surface microstructures in ion-implanted host materials.

ZnAl2O4 spinel has been formed in Al2O3 by ion implantation. Sequential implantation of Zn and 0 in overlapping profiles followed by annealing in Ar + H2 gives rise to a nearly continuous epitaxial layer of ZnAl2O4 oriented with (111) planes parallel to (0001) planes of Al2O3. If only Zn is implanted, then discrete bands of ZnAl2O4 oriented with (422) planes parallel to (0001) planes of Al2O3 are produced. By similar methods, oriented MgAl2O4 spinel also has been produced in Al2O3 by sequential Mg + O implantation.

Synthetic ZrSiO4, HfSiO4, and ThSiO4 single-crystal specimens were irradiated by 800 keV Kr+ ions, and the microstructural evolution was observed in-situ in a transmission electron microscope. All three compounds were found to become amorphous up to temperatures in excess of 600°C. Using a new model, the activation energies for annealing were found to be in the range of 3.1 to 3.6 eV for these compounds. At temperatures above 600°C, the orthosilicates were observed to decompose into the component oxides (e.g., tetragonal ZrO2 + amorphous SiO2 in the case of zircon). A single-crystal zircon specimen was also irradiated with a pulsed picosecond Nd:YAG laser operated at 355 nm, and the resulting microstructure was investigated by optical absorption, SEM, AFM, and TEM techniques.

A comparative study was undertaken of Amazonian fish diversity and density (abundance and biomass) in nutrient poor (blackwater) and richer (whitewater – várzea) habitats in the vicinity of Tefé, Brazil. The whitewater sampling sites, in the floodplain of the Rios Solimōes and Japurá, had high turbidity (Secchi disc 0.03–0.7 m), a conductivity of 64–110 μS cm–1 at 25°C and a pH of 6.6–6.9. The blackwater sites Lagos Amanã, Iamã and Tefé had a low turbidity (Secchi disc 2.0–2.2 m), a conductivity of 7–11 μS cm–1 at 25°C and a pH of 5.3–6.0. The fish communities of open water, floating meadow and forest margin were sampled. Both whitewater and blackwater sites held high diversity fish communities with many species in common. Whitewater habitats were more diverse yielding 108 species, compared with only 68 from blackwater. Fish density within floating meadow was estimated during high water April and May 1994, and low water October 1994 and March 1995. During the high water season fish biomasses in blackwater lakes (31.1 gm–2) were significantly greater than those of either whitewater lakes (13.4 gm–2) or whitewater river channels (3.45 g m–2). At low water, in October, whitewater channels were generally found to hold the highest fish biomass (204 g m–2) although in March a blackwater site yielded the highest fish biomass recorded (285.9 g m–2). The amount of floating meadow habitat within Whitewaters is however much greater than that in blackwaters. It is suggested that blackwaters may offer a stable habitat resulting in a high standing crop. In comparison, variation in conditions such as dissolved oxygen concentration in the whitewater may limit standing crop, but still allow periods of high productivity. Evidence was found for migration of fish from várzea lakes during periods of low oxygen availability. The high diversity and biomass of fish caught in both whitewater and blackwater lakes indicates that water acidity and conductivity are poor predictors of fish diversity and density in tropical floodplain lakes.

Parasuicide is not a single syndrome. Subtypes at present recognized are based largely on clinically derived stereotypes. When considering a series of patients, the clinician is unable to handle more than a few attributes at a time. This paper describes the application of three very different clustering algorithms to a material of 350 treated parasuicide patients. Mathematically, three types emerge. Clinically, two of these are interpretable and make sense. The types established are: I (n = 107) a group not characterized by any of the variables we examined; this group is a puzzle, mainly because the reasons for the parasuicidal act are not clear. II (n = 132) a depressed, alienated group with high life-endangerment. III (n = 111) a group whose act was highly operant: they felt alienated and were angry with others. These groups did not differ significantly on demographic variables. The usefulness of this typology, particularly for management, after-care and prevention, has now to be assessed.