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Review of models of the near-Earth space radiation environment is presented, including recent developments in trapped proton and electron, galactic cosmic ray and solar particle event models geared toward spacecraft electronics applications.

The radiation belts and plasma in the Earth’s magnetosphere pose hazards to satellite systems which restrict design and orbit options with a resultant impact on mission performance and cost. For decades the standard space environment specification used for spacecraft design has been provided by the NASA AE8 and AP8 trapped radiation belt models. There are well-known limitations on their performance, however, and the need for a new trapped radiation and plasma model has been recognized by the engineering community for some time. To address this challenge a new set of models, denoted AE9/AP9/SPM, for energetic electrons, energetic protons and space plasma has been developed. The new models offer significant improvements including more detailed spatial resolution and the quantification of uncertainty due to both space weather and instrument errors. Fundamental to the model design, construction and operation are a number of new data sets and a novel statistical approach which captures first order temporal and spatial correlations allowing for the Monte-Carlo estimation of flux thresholds for user-specified percentile levels (e.g., 50th and 95th) over the course of the mission. An overview of the model architecture, data reduction methods, statistics algorithms, user application and initial validation is presented in this paper.

Two mineral oils and 12 linear primary alcohols were studied, alone and in combination, to determine their contact toxicity to adult German cockroaches, Blattella germanica (L.) (Dictyoptera: Blattellidae). The more toxic oil, PD23 (LD50 = 1.45 mg per cockroach) was used for combination studies. Alcohols with carbon chain lengths of C3 and C8 through C12 were the most toxic, with LD50 values ranging from 0.3 to 0.6 mg. C1 (methanol) and C14 (1-tetradecanol) were least toxic, with LD50 values of 2.35 and 1.75 mg, respectively. Eight of the 12 combinations of a nonlethal dose of PD23 oil with an LD10 dose of alcohol produced significantly greater mortality than predicted under the assumption of additive effects. A sample of five synergistic oil + alcohol combinations, covering most of the alcohol carbon chain length range over which synergy occurred, was further studied by calculating LD50 values for three fixed mixture ratios (80:20, 50:50, and 20:80) of each combination. Results were analyzed using both graphical techniques (isobole analysis) and by nonlinear regression. At least one, but not necessarily all, of the three fixed ratio combinations of each oil + alcohol pairing indicated synergy. The conclusions drawn from the isobole and regression analyses were consistent.

This study examined ego resilience and engagement coping as mediators of the relationships between supportive and controlling parenting practices and early adolescents’ academic achievement, social competence, and physical health. Participants were 240 predominantly Mexican American early adolescents, their parents, and their teachers. There were significant positive correlations between supportive parenting and ego resilience and between ego resilience and achievement, social functioning, and health. Supportive parenting was also positively related to engagement coping, which in turn was positively related to achievement and health. Controlling parenting was significantly negatively related to ego resilience but not engagement coping. As hypothesized, ego resilience mediated relationships between supportive or controlling parenting and outcomes. Engagement coping mediated relationships between supportive parenting and academic achievement and supportive parenting and physical health. Findings support the roles of ego resilience and engagement coping in positive functioning across fundamental domains of development.

We demonstrate a new method of analyzing observed storm-time pitch-angle distributions to obtain information regarding the appropriate choice of the pitch-angle diffusion coefficients. We apply this method to MeV electrons in the outer zone as a diagnostic of the relative contribution of electromagnetic ion-cyclotron (EMIC) waves and whistler-mode hiss and chorus. We assume EMIC and hiss are confined to a plasmaspheric plume (hence, “plume waves”), with chorus prevalent over large portions of the day and night side. First, we determine the eigenmodes and eigenvalues of the pitch-angle diffusion operator predicted by quasilinear diffusion theory and approximate chorus, hiss, or EMIC plasma wave parameters for energetic electrons in the outer zone. Then, by projecting pitch-angle distributions observed by CRRES into the eigenmodes, we determine whether the pitch-angle distributions are consistent with the assumed diffusion process for various relative weighting of chorus and plume waves. Eigenmodes with shorter decay times (i.e., larger negative eigenvalues) ought to represent a comparatively smaller portion of the total flux in the pitch-angle distribution. We show that several observed pitch-angle distributions are consistent with predominantly chorus-driven pitch-angle diffusion, with at most a minor contribution from plume waves.

On January 20, 2005 there was an X 7.1 solar flare at 0636 UT with an accompanied halo coronal mass ejection (CME). The resultant interplanetary shock impacted earth ∼36 h later. Near earth, the Advanced Composition Explorer (ACE) spacecraft observed two impulses with a staircase structure in density and pressure. The estimated earth-arrival times of these impulses were 1713 UT and 1845 UT on January 21, 2005. Three MINIature Spectrometer (MINIS) balloons were aloft on January 21st; one in the northern polar stratosphere and two in the southern polar stratosphere. MeV relativistic electron precipitation (REP) observed by all three balloons is coincident (

Osteochondral defects of the lateral trochlear ridge of the distal femur were identified in 15 joints of 10 horses. Lesions were bilateral in five horses and unilateral in five horses. Thirteen of these 15 defects were treated by curettage through a craniolateral femoropatellar arthrotomy. Subcutaneous seroma formation and partial skin dehiscence occurred in nine stifles. Lameness attributable to the stifle joint was no longer apparent at 6 and 12 months after surgery. The normal subchondral bony contour of the lateral trochlear ridge was altered in all joints after surgery. The subchondral bone was uniformly increased in density in all joints, and six lateral trochlear ridges had small focal radiolucent regions within the subchondral bone, which suggested that complete removal of the original lesion had not been achieved. Healing of the surgical site between 2 weeks and 14 months was evaluated in four joints. Granulation tissue from mesenchymal elements in subchondral marrow spaces gradually filled the defects with fibrocartilage.

We describe a tabular specification model of the density and temperature of ions and electrons at geosynchronous orbit as a function of magnetic local time and solar wind parameters. This model can be used to provide boundary conditions for numerical ring current models. Unlike previous specification models of geosynchronous plasma moments, this model is parameterized by upstream solar wind conditions. We find that solar wind parameters are a better predictor of geosynchronous ion density than magnetospheric indices, and as upstream parameters they are often more appropriate as model inputs since they causally precede the model outputs. Of the upstream parameters that were tested, the best predictors of geosynchronous conditions were the solar wind flow pressure and the magnitude and Z -component of the interplanetary magnetic field.

Effects of the South Atlantic Anomaly (SAA) on spacecraft in low Earth orbit (LEO) are well known and documented. The SAA exposes spacecraft in LEO to high dose of ionizing radiation as well as higher than normal rates of Single Event Upsets (SEU) and Single Event Latch-ups (SEL). CubeSats, spacecraft built around 10 x 10 x 10 cm cubes, are even more susceptible to SEUs and SELs due to the use of commercial off-the-shelf components for electronics and payload instrumentation. Examination of the SAA using both data from the Defense Meteorological Satellite Program (DMSP) and a new set of models for the flux of particles is presented. The models, AE9, AP9, and SPM for energetic electrons, energetic protons and space plasma, were developed for use in space system design. These models introduce databased statistical constraints on the uncertainties from measurements and climatological variability. Discussion of the models’ capabilities and limitations with regard to LEO CubeSat design is presented.

The influence of compression and shear loads on the strength of composite laminates with z-pins is evaluated parametrically using a 2D Finite Element Code (FLASH) based on Cosserat couple stress theory. Meshes were generated for three unique combinations of z-pin diameter and density. A laminated plate theory analysis was performed on several layups to determine the bi-axial stresses in the zero degree plies. These stresses, in turn, were used to determine the magnitude of the relative load steps prescribed in the FLASH analyses. Results indicated that increasing pin density was more detrimental to in-plane compression strength than increasing pin diameter. Compression strengths of lamina without z-pins agreed well with a closed form expression derived by Budiansky and Fleck. FLASH results for lamina with z-pins were consistent with the closed form results, and FLASH results without z-pins, if the initial fiber waviness due to z-pin insertion was added to the fiber waviness in the material to yield a total misalignment. Addition of 10% shear to the compression loading significantly reduced the lamina strength compared to pure compression loading. Addition of 50% shear to the compression indicated shear yielding rather than kink band formation as the likely failure mode. Two different stiffener reinforced skin configurations with z-pins, one quasi-isotropic and one orthotropic, were also analyzed. Six unique loading cases ranging from pure compression to compression plus 50% shear were analyzed assuming material fiber waviness misalignment angles of 0, 1, and 2 degrees. Compression strength decreased with increased shear loading for both configurations, with the quasi-isotropic configuration yielding lower strengths than the orthotropic configuration.

The outer radiation belt injection, transport, acceleration and loss satellite (ORBITALS) is a small satellite mission proposed as a Canadian contribution to the satellite infrastructure for the International Living With a Star (ILWS) program. The ORBITALS will monitor the energetic electron and ion populations in the inner magnetosphere across a wide range of energies (keV to tens of MeV) as well as the dynamic electric and magnetic fields, waves and cold plasma environment which govern the injection, transport, acceleration and loss of these energetic and space weather critical particle populations. ORBITALS will be launched around 2010–2012 into a low-inclination GTO-like orbit which maximizes the long-lasting apogee-pass conjunctions with both the ground-based instruments of the Canadian Geospace Monitoring (CGSM) array as well as with the GOES East and West and geosynchronous communications satellites in the North American sector. Specifically, the ORBITALS will make the measurements necessary to gain fundamental new understanding of the relative importance of different physical acceleration and loss processes which are hypothesised to shape the energetic particle populations in the inner magnetosphere. The ORBITALS will also provide the raw radiation measurements at MEO altitudes necessary for the development of the next-generation of radiation belt specification models, and on-board experiments will also monitor the dose, single-event upset, and deep-dielectric charging responses of electronic components on-orbit. In this paper we outline the scientific objectives of the ORBITALS mission, discuss how the ORBITALS will lead to solutions to outstanding questions in inner magnetospheric science, and examine how the ORBITALS will complement other proposed inner magnetosphere missions in the ILWS era.

The relative sensitivity of radiography, computed tomography, and magnetic resonance imaging for detecting palmar process fractures of the distal phalanx in foals was determined and the imaging findings were compared with histomorphologic evaluations of the palmar processes. Compared to radiography, computed tomography and magnetic resonance imaging did not improve the sensitivity for detection of palmar process fractures. Statistical agreement for palmar process fracture diagnosis was excellent among the three imaging modalities. Histomorphologic evaluations were more sensitive for diagnosis of palmar process fracture than any of the imaging modalities. Three-dimensional image reconstructions and volume measurements of distal phalanges and palmar process fracture fragments from computed tomography studies provided more complete anatomical information than radiography. Magnetic resonance imaging confirmed that the deep digital flexor tendon insertion on the distal phalanx is immediately axial to the site where palmar process fractures occur, and differentiated cartilage, bone, and soft tissue structures of the hoof.

We present results from a rank order correlation coefficient (ROCC) analysis between ground-based 1-10 mHz ultra-low frequency (ULF) wave power, upstream solar wind speed (v SW ), and MeV electron flux across the outer radiation belt. We use data spanning a complete solar cycle (1990-2001) from ground magnetometers from the SAMNET and IMAGE arrays, and MeV electron data from the Los Alamos spacecraft at geosynchronous orbit (GEO) and from a HEO spacecraft at L = 5.5 and 4.5. We find a very high correlation between ULF wave power and r SW at all local times and on all L-shells between L = 3.1 and 6.6. Very strong cross-L-shell ULF power coherence is maintained throughout the solar cycle, although the efficiency of r SW in driving a given ULF power response is solar cycle dependent. Peak ULF power and peak ROCC (∼0.75) are observed during the declining phase of the solar cycle around 1994-1995, with smaller localised peaks in these parameters occurring during slower average v SW conditions close to solar maximum in 2000. There is also a strong correlation of both v SW and ULF power with MeV electron flux, these correlations being more strongly dependent on solar cycle phase. The v SW and ULF power correlations with MeV electron flux peak during the late declining phase of the solar cycle, when the radiation belts are most intense. Our results confirm that radiation belt flux demonstrates extremely strong global cross-L-shell coherence throughout the solar cycle. The ROCC between v SW or ULF power and MeV electron flux demonstrate a clear and systematic time lag following the peak in either v SW or ULF power. Electron fluxes respond first at GEO (lag ∼ 2 days), before subsequently peaking at lower L-shells. Importantly, our results indicate that u SW -correlated MeV electron acceleration processes operate by inwards radial transport. The correlation between ULF power and MeV energy electron flux further suggests that ULF waves could be causally responsible via ULF wave enhanced radial diffusion.

OBJECTIVE To estimate the likelihood of poor surgical results being explained by chance rather than under-performance. METHODS The 30-day mortality rates after radical cystectomy for bladder cancer were analysed theoretically. Surgical competence was defined as a mortality rate of 4%, excellence as 2% and under-performance as 8%, 12%, 20% or 40%. Four scenarios were explored for surgeons of different competence: first, the sample size required to show that a given level of under-performance is very unlikely to be due to chance; second, the likelihood of two or more consecutive deaths in a series of cases; third, the likelihood of clustering of deaths, defined as two deaths in five or in 10 cases; and last, the likelihood of outstanding surgical results (i.e. no deaths) being achieved in small cohorts by surgeons of differing competence. RESULTS For surgeons with a mortality rate of 8%, 12%, 20% or 40%, the sample sizes needed to prove under-performance are 211, 65, 21 and seven, respectively. For consecutive deaths, 0.4% of excellent, 1.4% of competent and 21% of surgeons with a mortality rate of 12% will experience two or more consecutive deaths in the next 10 cases. For clustered deaths, 1% of excellent, 5% of competent and 23% of seriously under-performing surgeons (mortality rates ≥ 12%) will experience two deaths in their next 10 cases. Lastly, for the likelihood of outstanding results, only 3.6% of surgeons with an 8% mortality rate and < 1% of surgeons with a mortality rate ≥ 12% will experience no deaths over 40 consecutive cases. CONCLUSIONS Very large cohorts are needed to confirm even significant under-performance. Consecutive deaths are very unlikely events for competent surgeons. Clustered deaths (two deaths in 10 cases) are very unlikely events for excellent surgeons but plausible for competent ones. Analysis of consecutive/clustered deaths is limited by low statistical sensitivity; only up to a quarter of seriously under-performing surgeons are identified. No deaths in 40 consecutive cases implies competence.

Small sub-component specimens consisting of solid laminates at the ends that transition to X-cor® truss sandwich in the center, were tested in a combination of three point bending, uni-axial tension, and combined tension and bending. The failure process in the transition region was documented for each loading using digital video and high-resolution cameras. For the three-point bending tests, most of the deformation occurred in the solid laminate regions on either end of the specimen. Some pin debonding from the skin of the X-cor® truss sandwich was observed in the transition region and was accompanied by audible “pings” throughout the loading. Tension loaded specimens failed in the sandwich skin in the middle of the gage length, accompanied by separation of the sandwich core from the back skin and by delamination between the top skin and bottom skin at the transition region. The pinging associated with pin debonding occurred as the load was increased. However, the frequency of the pinging exceeded any visual observations of pin debonding in the video of the transition region. For specimens tested in combined tension and bending, the greatest amount of pinging occurred during initial application of the axial load. High-resolution images in the transition region indicated that the pinging corresponded to pins debonding and buckling due to the through-thickness Poisson contraction of the specimen. This buckling continued to a much smaller extent as the transverse load was applied.

The influence of two-dimensional finite element modeling assumptions on the debonding prediction for skin-stiffener specimens was investigated. Geometrically nonlinear finite element analyses using two-dimensional plane-stress and plane-strain elements as well as three different generalized plane-strain type approaches were performed. The computed skin and flange strains, transverse tensile stresses and energy release rates were compared to results obtained from three-dimensional simulations. The study showed that for strains and energy release rate computations the generalized plane-strain assumptions yielded results closest to the full three-dimensional analysis. For computed transverse tensile stresses the plane-stress assumption gave the best agreement. Based on this study it is recommended that results from plane-stress and plane-strain models be used as upper and lower bounds. The results from generalized plane-strain models fall between the results obtained from plane-stress and plane-strain models. Two-dimensional models may also be used to qualitatively evaluate the stress distribution in a ply and the variation of energy release rates and mixed mode ratios with delamination length. For more accurate predictions, however, a three-dimensional analysis is required.

The Sulawesi subspecies of the Philippine Megapode, Megapodius cumingii gilbertii, most commonly lays its eggs in decaying roots of dead trees. We measured 14 environmental variables describing the dead tree and surrounding forest at incubation sites and random points in the Tangkoko-DuaSudara Nature Reserve, North Sulawesi, Indonesia. Incubation sites were not selected randomly by the Philippine Megapode but were located in areas with specific environmental characteristics. A Discriminant Function Analysis produced a clear separation between incubation sites and random points based primarily on ten variables. Relative to random points, incubation sites were located at the base of very large dead trees, disproportionately Alstonia ranvolfia, with their trunks standing and unbroken, and root plates in the ground. Incubation sites were in areas that were less disturbed than random points, with a relatively high and closed canopy, more large trees, and a less dense understorey. We consider that variables associated with incubation sites provide in situ a large biomass of decaying roots (for heat generation from microbial decomposition) while being under a closed canopy (for protection from desiccation and fluctuations in air temperature). Research is required into the effects of habitat modification on the Philippine Megapode and other members of the Megapodiidae. Until such studies are undertaken, we recommend that resource managers protect areas of relatively undisturbed mature closed forest in order to conserve the Philippine Megapode.

A new set of models, AE9/AP9/SPM, has been developed for use in space system design and other climatological applications. They describe energetic electron, proton, and plasma fluxes in the Earth’s inner magnetosphere based on 30 independent data sets from satellite-based sensors. The models provide particle flux maps including estimates of both measurement uncertainties and space weather variability. Furthermore, the model architecture permits the Monte-Carlo estimation of the time evolution of fluxes and derived quantities, e.g. the median and 95th percentile, along an arbitrary orbit. This overview will particularly address the latest AE9/AP9 version release.

Relativistic electrons appear in the geosynchronous environment following some, but not all, geomagnetic storms. The ability to identify which storms produce these electrons would bring us much closer to explaining the mechanism responsible for their appearance, and it would provide the space weather community with a means to anticipate the electron hazard to geosynchronous spacecraft. We apply a recently developed statistical technique to produce an hourly time series of relativistic electron conditions at local noon along geosynchronous orbit using several geosynchronous monitors. We use a cross-correlation analysis to determine what parameters in the solar wind and magnetosphere might influence the flux of relativistic electrons. We then perform a superposed epoch analysis to compare storms with and storms without the appearance of these electrons. We investigate a number of solar wind and magnetospheric parameters for these two sets of storms at 1-hour resolution. In particular, sustained solar wind velocity in excess of 450 km s−1 is a strong external indicator of the subsequent appearance of relativistic electrons. In the magnetosphere, long-duration elevated Pc 5 ULF wave power during the recovery phase of magnetic storms appears to discriminate best between those storms that do and do not produce relativistic electrons.

Preconception care (PCC) and strict periconceptional glycemic control are both used to minimize the risk of congenital birth defects in offspring of women with type 1 or type 2 diabetes mellitus (DM). These malformations are ascribed in large measure to poor periconceptional control. This study evaluated PCC by a meta-analysis of published studies of PCC in women with DM, published from 1970 to 2000. Two reviewers independently abstracted the data, and the rate and relative risk (RR) of major and minor malformations were pooled from eligible studies using a random effects model. Early first-trimester values of glycosylated hemoglobin were recorded. Eight retrospective and eight prospective cohort studies were included; they were carried out in Europe, the United Kingdom, the United States, and Israel. Most participants had type 1 DM, but three studies included women with type 2 DM. Women given PCC tended to be about 2 years older on average than the others. Methods of PCC were quite variable, although most centers provided some maternal education about the pregnancy risks associated with poor glycemic control. In seven studies reporting early gestational glycosylated hemoglobin values, mean levels were consistently lower in PCC patients. Among 2104 offspring, the pooled rate for major and minor anomalies was 2.4% in the PCC group and 7.7% in non-PCC recipients, for a pooled RR of 0.32. Among 2651 offspring, major malformations were less prevalent in the PCC group (2.1 vs. 6.5%; pooled RR = 0.36). Comparable results were obtained when only prospective studies were analyzed and in studies where the infant examiners were unaware of the mothers' PCC status. The lowest risk of major anomalies was in a study that administered folic acid periconceptionally to its PCC recipients; the RR was 0.11. This meta-analysis, which included both retrospective and prospective studies, demonstrates an association of PCC with a significantly lower risk of congenital anomalies in the offspring of women with established DM. The lowered risk was accompanied by significantly lower glycosylated hemoglobin values in the first trimester in recipients of PCC.

Objectives: To study the pharmacokinetics of lithium chloride administered intravenously to patients who had undergone cardiac surgery within the previous 12 h and to normal volunteers, since lithium is used in a new indicator dilution method for measuring cardiac output. Methods: A prospective study was carried out in a London teaching hospital. Lithium chloride was administered intravenously and blood samples taken at intervals for up to one hour. Plasma lithium levels were measured by inductively coupled plasma optical emission spectrometry and standard pharmacokinetic parameters were calculated. Results: Two groups of patients were investigated; the first (n = 10) received five doses of 0.6 mmol LiCl at 2 min intervals, the second (n = 10) a single dose of 0.6 mmol LiCl. A further group of six normal volunteers also received a single dose of 0.6 mmol LiCl. Biexponential curves were fitted to the data. For the three groups the half-lives of the first exponentials (T1/2α) were 3.3, 4.2 and 3.9 min, resp...

Three models for the evolution of the ring current index Dst are evaluated for real-time implementation. Each model provides the time evolution of Dst in terms of solar wind parameters. Real-time data resources employed by the models are Kyoto Quicklook Dst and ACE real-time solar wind parameters. The implementation described provides a forecast time of about 1h due to propagation of the solar wind from the ACE spacecraft to the Earth. The models are evaluated for simulated real-time data availability, and several error measures are provided. One-hour averages were used in keeping with the standard Dst index. By all measures used the model of O'Brien and McPherron (1999, Journal of Geophysical Research, in press) performs best.

A consistent step-wise approach is presented to investigate the damage mechanism in composite bonded skin/stringer constructions under uniaxial and biaxial (in-plane/out-of-plane) loading conditions. The approach uses experiments to detect the failure mechanism, computational stress analysis to determine the location of first matrix cracking and computational fracture mechanics to investigate the potential for delamination growth. In a first step, tests were performed on specimens, which consisted of a tapered composite flange, representing a stringer or frame, bonded onto a composite skin. Tests were performed under monotonic loading conditions in tension, three-point bending, and combined tension/bending to evaluate the debonding mechanisms between the skin and the bonded stringer. For combined tension/bending testing, a unique servohydraulic load frame was used that was capable of applying both in-plane tension and out-of-plane bending loads simultaneously. Specimen edges were examined on the microscope to document the damage occurrence and to identify typical damage patterns. For all three load cases, observed failure initiated in the flange, near the flange tip, causing the flange to almost fully debond from skin. In a second step, a two dimensional plane-strain finite element model was developed to analyze the different test cases using a geometrically nonlinear solution. For all three loading conditions, computed principal stresses exceeded the transverse strength of the material in those areas of the flange where the matrix cracks had developed during the tests. In a third step, delaminations of various lengths were simulated in two locations where delaminations were observed during the tests. The analyses showed that at the loads corresponding to matrix ply crack initiation computed strain energy release rates exceeded the values obtained from a mixed mode failure criterion in one location. Hence, unstable delamination propagation is likely to occur as observed in the experiments.

Changes in actin organization in the living egg apparatus of Torenia fournieri from anthesis to post-fertilization have been investigated using microinjection and confocal microscopy. Our results revealed that the actin cytoskeleton displays dramatic changes in the egg apparatus and appears to coordinate the events of synergid degeneration, pollen tube arrival and gametic fusion during fertilization. Synergid degeneration occurs after anthesis and is accompanied by actin fragmentation and degradation. The actin cytoskeleton becomes organized with numerous aggregates in the chalazal end of the degenerating synergid, and some of the actin infiltrates into the intercellular gap between synergids, egg and central cell, forming a distinct actin band. An actin cap is present near the filiform apparatus after anthesis and disappears after pollen tube arrival. In the egg cell, actin filaments initially organize into a network and after pollination become fragmented into numerous patches in the cortex. These structures, along with the actin in the degenerating synergid and intercellular spaces form two distinct actin coronas during fertilization. The actin coronas vanish after gametic fusion. This is the first report of changes in actin organization in the living egg apparatus. The reorganization of the actin cytoskeleton in the egg apparatus and the presence of the actin coronas during fertilization suggest these events may be a necessary prelude to reception of the pollen tube and fusion of the male and female gametes.

Objective— To determine the effects of intraarticular administration of Samarium-153 (153Sm) bound to hydroxyapatite microspheres (153SmM) on an osteochondral chip–Ninduced synovitis. Study Design— Sixty days after implantation of autogenous osteochondral fragments in the middle carpal and metacarpophalangeal joints, 153SmM was administered into 1 joint of each type. The contralateral joints were used as untreated controls. Animals or Sample Population— Fifteen horses without preexisting joint disease were randomly divided into 2 groups (7 in the carpal group, 8 in the metacarpophalangeal group). Methods— Horses had osteochondral fragments that were harvested from the lateral ridge of the trochlea of the talus and implanted bilaterally into a middle carpal joint and a metacarpophalangeal joint; the opposite joint type served as a control. Sixty days later, 10 to 15 mCi of 153SmM (20 to 50 μm diam) was injected into the fragment-implanted joints. Three horses were treated with nonradioactive hydroxyapatite fragments. Horses were examined clinically until they were killed 14 or 30 days later. Control and treated joints were examined grossly and microscopically to determine the effects of 153SmM on synovial membrane and cartilage. Results— Intraarticular 153SmM caused a transient flare with lameness, effusion, and edema for 48 to 72 hours. Implanted osteochondral chips induced a synovitis characterized by variable degrees of joint damage and synovial infiltrate. Use of 153SmM resulted in synovectomy of variable depth and extent. Conclusions— Intraarticular 153SmM may be a useful method for synovectomy of inflamed synovial membrane. Clinical Relevance— With further testing, radioactive pharmaceuticals might become useful clinical treatments for persistent synovitis not responsive to conventional techniques.

This empirical analysis of the terrestrial ring current, as measured by Dst, uses conditional probability density in Dst phase space to determine the evolution of the ring current. This analysis method does not assume a dynamic equation, but merely requires that the evolution of Dst depends on Dst and the solar wind. Our simple model, with seven nontrivial parameters, describes the dynamics of 30 years of hourly Dst with solar wind data provided by the OMNI database. The solar wind coupling is assumed to be determined by VBs. We arrive at a dynamic equation nearly identical to the Burton equation (Burton et al., 1975) with a slight correction. The method is restricted to Dst > −150 nT owing to the rarity of larger excursions. We show that the ring current decay lifetime varies with VBs but not with Dst, and we relate this variation to the position of convection boundaries in the magnetosphere. Convection boundaries closer to the Earth result in shorter charge exchange decay times owing to the higher neutral density near the Earth. The decay time in hours varies as τ = 2.40 exp [9.74/(4.69+VBs)] with VBs in millivolts per meter. We also show that the energy injection function as derived by Burton et al. is essentially correct. The injection Q is zero for VBs Ec. We derive the correction for magnetopause contamination: Dst* = Dst −7.26P1/2 + 11 nT, where P is solar wind dynamic pressure in nanopascals. Finally, we apply the model to a moderate storm and to an intense storm. We demonstrate that, in spite of the fact that spacecraft observe compositional changes in the ring current at intense Dst, the dynamics of the two storms are not obviously different in the context of our model. We demonstrate that the generally observed dependence of the decay parameter on Dst is actually an alias of the coincidence of intense Dst and intense VBs.

The hair follicle is characterized by cyclic transformations from active growth and hair fiber production through regression into a resting phase. The growth phase, known as anagen, is associated with rapid rates of cell turnover, and variations in the rate of DNA synthesis in mouse skin throughout the hair cycle are accompanied by changes in the activity of ornithine decarboxylase (ODC), a key enzyme in the synthesis of polyamines, which are actively involved in regulation of normal cell division, differentiation, and growth. Previously, a transgenic mouse was created that overexpressed ODC in the skin using a K6 promoter. The first hair cycle in neonatal transgenic mice appeared to be normal, but by the third week of postnatal life transgenic pups begin to progressively lose hair. The lower portion of the hair follicle was progressively replaced with enlarging cystic structures located in the deep dermis, and the transgenic mice exhibited excessive growth of skin mass resulting in pronounced wrinkling and folding. Interestingly, these findings bore striking resemblance to the rhino mouse phenotype and to human patients with papular atrichia, a rare congenital ectodermal disorder characterized by progressive and irreversible hair loss in early childhood. The similarities in phenotype between transgenic mice and human atrichia with papular lesions suggest that ODC transgenics may represent a useful model for studying this disorder. It appears that ODC plays a functionally important, yet still obscure role in a complex metabolic pathway that is critical in hair follicle function not only in mice, but in humans as well.

An empirical model of the factors that determine the central axis dose at 10 cm depth in water for 4 MV, 6 MV and 18 MV photon beams is presented. Backscattering from the variable collimators into the dose monitoring ionization chamber can cause a variation of -0.5% to +1.8% in the dose per monitor unit in accelerators with an electron facility. Forward emission towards the isocentre from the beam flattening filter and upper collimators is more dependent on the position of the upper variable collimator blades than the lower blades, so that they are not interchangeable in determining output factors, which can differ by up to 2%. The model includes the product of the monitor backscatter factor, normalized phantom scatter factor, normalized head scatter factor and inverse square law, corrected for the displacement of the virtual x-ray focus from the target. It can predict the dose to -/+0.83% for 4 MV, -/+0.80% for 6 MV photons and -/+0.82% for 18 MV photons. The normalized head scatter factor is a second-order polynomial of the modified equivalent square collimator, whose coefficients do not vary significantly with x-ray energy. The model was tested by comparison with independent measurements of output factor and generally agreed to around 1%.

The social repertoire of Sulawesi macaques is presented, based upon data recorded both in the wild and from captive populations. The repertoire describes behaviors observed in social contexts, including communication patterns, movement patterns, sexual patterns, infant-related and play behaviors, and triadic interactions. Most of these behavior patterns are shared by all known Sulawesi taxa. The form or function of certain patterns depart significantly from what has been reported in other macaques, while particular similarities may be linked to phylogenetic relationships within the genus Macaca.

Sera from 516 participants enrolled in a population-based cross-sectional study in northwest Tanzania were tested for antibodies to hepatitis C virus (HCV). The mean age of study subjects was 29 years (range = 16-49 years); 43% were men, 6% reported a history of blood transfusion, and 4% were infected with human immunodeficiency virus-1 (HIV-1). Although 53 of 516 sera (10.3%, 95% confidence interval [CI] = 7.8-13.2%) were repeatedly reactive by a third-generation enzyme immunoassay (EIA-3), only 6 of the 53 were positive when tested with a third-generation recombinant immunoblot assay (confirmed HCV seroprevalence = 1.2%, 95% CI = 0.4-2.5%). The positive predictive value of the HCV EIA-3 in this population was 18.8% (95% CI = 7.0-36.4%). False positivity was not correlated with EIA-3 optical density values, age, sex, infection with HIV-1, or a history of blood transfusion, but it was marginally associated with increased serum IgG levels. We conclude that the prevalence of HCV is low in this region and that the HCV EIA-3 has a higher false-positivity rate in this population than has been reported among U.S. blood donors.

Objective.We have previously described an indicator dilutiontechnique of measuring cardiac output in which lithium chloride is injectedas a bolus via a central venous catheter and cardiac output derived from thearterial lithium dilution curve recorded from a lithium-selective electrode,which we have developed for this purpose. It would be an advantage if thelithium could be injected via the basilic vein (in the antecubital fossa) inthose patients who do not need central venous catheterisation for otherreasons. We have therefore compared cardiac output measurements made usingthese two routes of lithium chloride administration. Methods.Lithiumdilution cardiac output was measured 10 times in each of 10 patients,injecting the lithium chloride alternately via the basilic or central venouscatheter. Results.The mean difference was 0.8 ± 5.2% (SD)(range −8.5 to +7.0%) over a range of cardiac output of 4.5–13l/min. Conclusions.Injection of lithium chloride via the basilic veinin the antecubital fossa allows accurate lithium dilution cardiac outputmeasurements to be made in patients who do not have central venous cathetersin place.

Electrons of energy several MeV or greater have been implicated in the failure and malfunction of geostationary spacecraft. It is therefore important to be able to specify and even forecast the fluxes of these particles during and following geomagnetic storms. A first step is the understanding of their relationship to lower-energy electrons that can already be well modeled. It is therefore the goal of this paper to examine the relative time, spatial, and spectral relationships between 1.5 MeV electrons and intermediate energy electrons down to about 100 keV. For the November 1993 geomagnetic storm we find that electrons from about 100 keV to 1.5 MeV at GEO can be conveniently characterized by a power law spectrum and that the slope and intercept of this spectrum vary in systematic ways during the storm. This suggests the possibility of developing prediction filters or artificial neural networks, driven by a storm activity indicator (such as Dst), local time and a lower-energy electron flux, to specify the energetic electron spectral characteristics. We further find that local time diurnal effects are an important contributor to the apparent time delay of the recovery of energetic electrons and when these effects are considered the recovery phase enhancement is nearly uniform across the spectrum. This paper will report the spatial and temporal morphology of these intermediate to energetic electrons, their characterization by a power law and the variations of the power law slope and intercept throughout the November 1993 storm. These temporal, spatial, and spectral properties suggest that the recovery phase enhancement is due to the entry of the intermediate energy electrons from the geomagnetic tail as part of the storm injection process. We also discuss our success at building an Artificial Neural Network system to specify the storm time energetic electron flux spectra.

The on-going efforts to achieve internationally accepted test standards for interlaminar fracture toughness over the past two decades will be reviewed. The status of current efforts to obtain an ISO standard for the Double Cantilever Beam test for mode I interlaminar fracture toughness will be highlighted. Current round robin activity underway to develop standards for mode II, mode III, and mixed-mode interlaminar fracture toughness will also be discussed. Differences in the interpretation of interlaboratory “round robin” test results will be highlighted. The influence of the different roles of standardization bodies in the US, Europe, and Japan on achieving international standards for interlaminar fracture toughness will be discussed.

Background Anesthetic induction and maintenance with propofol are associated with decreased blood pressure that is, in part, due to decreased peripheral resistance. Several possible mechanisms whereby propofol could reduce peripheral resistance include a direct action of propofol on vascular smooth muscle, an inhibition of sympathetic activity to the vasculature, or both. This study examined these two possibilities in humans by measuring the forearm vascular responses to infusions of propofol into the brachial artery (study 1) and by determining the forearm arterial and venous responses to systemic (intravenous) infusions of propofol after sympathetic denervation of the forearm by stellate blockade (study 2). Methods Bilateral forearm venous occlusion plethysmography was used to examine forearm vascular resistance (FVR) and forearm vein compliance (FVC). Study 1 used infusion of intralipid (time control) and propofol at rates between 83 and 664 micrograms/min into the brachial artery of 11 conscious persons and compared responses to arterial infusions of sodium nitroprusside (SNP) at 0.3, 3.0, and 10 micrograms/min. Venous blood from the infusion arm was assayed for plasma propofol concentrations. In study 2, after left stellate block (12 ml 0.25% bupivacaine + 1% lidocaine), six participants were anesthetized and maintained with propofol infusions of 125 and 200 micrograms.kg-1.min-1. Simultaneous right forearm (unblocked) blood flow dynamics served as the time control. In three additional conscious participants, intrabrachial artery infusions of SNP and nitroglycerin, both at 10 micrograms/min, were performed before and after stellate blockade of the left forearm to determine whether the sympathetically denervated forearm vessels could dilate beyond the level produced by denervation alone. Results In study 1, infusion of intralipid or propofol into the brachial artery did not change FVR or FVC. Sodium nitroprusside significantly decreased FVR in a dose-dependent manner by 22 +/- 5%, 65 +/- 3%, and 78 +/- 2% (mean +/- SEM) but did not change FVC. During the incremental propofol infusions, plasma propofol concentrations increased from 0.2 to 10.1 micrograms/ml and averaged 7.4 +/- 1.1 micrograms/ml during the highest infusion rate. In study 2, stellate ganglion blockade decreased FVR by 50 +/- 6% and increased FVC by 58 +/- 10%. Propofol anesthesia at 125 and 200 micrograms.kg-1.min-1 progressively reduced mean arterial pressure. In the arm with sympathetic denervation, FVR and FVC showed no further changes during propofol anesthesia, whereas in the control arm FVR significantly decreased by 41 +/- 9% and 42 +/- 7%, and FVC increased significantly by 89 +/- 27% and 85 +/- 32% during 125 and 200 micrograms.kg-1.min-1 infusions of propofol, respectively. In the three additional conscious participants, intraarterial infusion of SNP and nitroglycerin (TNG) after the stellate blockade resulted in a further decrease of FVR and a further increase of FVC. Conclusions In contrast to SNP infusions, propofol infusions into the brachial artery of conscious persons caused no significant vascular responses, despite the presence of therapeutic plasma concentrations of propofol within the forearm. The effects of propofol anesthesia on FVR and FVC are similar to the effects of sympathetic denervation by stellate ganglion blockade. Thus the peripheral vascular actions of propofol appear to be due primarily to an inhibition of sympathetic vasoconstrictor nerve activity.

Externalizing behaviors (encompassing antisocial, impulsive, and substance use behaviors) are pervasive and impairing across a multitude of settings and developmental contexts. These behaviors, though often investigated separately, are highly comorbid. Prenatal tobacco exposure in interaction with various genetic influences has predicted later externalizing behavior, and recent evidence supports investigating sex differences in these patterns. In the current study, we extend this work by (a) examining two functional genetic markers in the dopamine system: the transporter gene ( DAT1 ) and the dopamine receptor D 4 gene ( DRD4 ) in interaction with prenatal tobacco exposure to predict a latent composite of externalizing behavior and (b) testing whether these patterns differ by sex of youth in a community sample of adolescents (n = 176). The relatively small sample is partially offset by high quality, multi-method prospective measurement. We assessed prenatal tobacco exposure using prospective repeated cotinine-corrected reports and externalizing behaviors were assessed utilizing multiple measures across three waves. The interaction between DAT1 (but not DRD4 ) and prenatal tobacco exposure was statistically significant in boys, and patterns appeared to differ by sex. Risk for externalizing behaviors for exposed boys increased linearly as a function of the 10r DAT1 allele. For exposed girls, there was a trend such that DAT1 heterozygotes had a marginally higher risk than homozygotes. This pattern was not explained by passive gene-environment correlation. Elucidating sex-specific pathways through which early adverse exposures and genetic susceptibilities contribute to externalizing behavior can inform early targeted prevention efforts for those children at highest risk.

The Arizona Twin Project is an ongoing longitudinal study designed to elucidate the genetic and environmental influences underlying the development of early competence and resilience to common mental and physical health problems during infancy and childhood. Participants are a sample of 600 twins (25% Hispanic) recruited from birth records in the state of Arizona, United States. Primary caregivers were interviewed on twins’ development and early social environments when twins were 12 and 30 months of age. Measures include indices of prenatal and obstetrical risk coded from hospital medical records, as well as primary caregiver-report questionnaires assessing multiple indicators of environmental risk and resilience (e.g., parental warmth and control, family and social support), twins’ developmental maturity, temperament, health, behavior problems, and competencies. Preliminary findings highlight the importance of the early environment for infant and toddler health and well-being, both directly and as a moderator of genetic influences. Future directions include a third longitudinal assessment in middle childhood examining daily bidirectional relations between sleep, health behaviors, stress, and mood.