Determining EMIC Wave Vector Properties Through Multi-Point Measurements: The Wave Curl Analysis.

Electromagnetic ion cyclotron (EMIC) waves play important roles in particle loss processes in the magnetosphere. Determining the evolution of EMIC waves as they propagate and how this evolution affects wave-particle interactions requires accurate knowledge of the wave vector, k. We present a technique using the curl of the wave magnetic field to determine k observationally, enabled by the unique configuration and instrumentation of the Magnetospheric MultiScale (MMS) spacecraft. The wave curl analysis is demonstrated for synthetic arbitrary electromagnetic waves with varying properties typical of observed EMIC waves. The method is also applied to an EMIC wave interval observed by MMS on October 28, 2015. The derived wave properties and k from the wave curl analysis for the observed EMIC wave are compared with the Waves in Homogenous, Anisotropic, Multi-component Plasma (WHAMP) wave dispersion solution and with results from other single- and multi-spacecraft techniques. We find good agreement between k from the wave curl analysis, k determined from other observational techniques, and k determined from WHAMP. Additionally, the variation of k due to the time and frequency intervals used in the wave curl analysis is explored. This exploration demonstrates that the method is robust when applied to a wave containing at least 3-4 wave periods and over a rather wide frequency range encompassing the peak wave emission. These results provide confidence that we are able to directly determine the wave vector properties using this multi-spacecraft method implementation, enabling systematic studies of EMIC wave k properties with MMS.

Charge-State-Dependent Energization of Suprathermal Ions During Substorm Injections Observed by MMS in the Magnetotail.

Understanding the energization processes and constituent composition of the plasma and energetic particles injected into the near-Earth region from the tail is an important component of understanding magnetospheric dynamics. In this study, we present multiple case studies of the high-energy (≳40 keV) suprathermal ion populations during energetic particle enhancement events observed by the Energetic Ion Spectrometer (EIS) on NASA's Magnetospheric Multiscale (MMS) mission in the magnetotail. We present results from correlation analysis of the flux response between different energy channels of different ion species (hydrogen, helium, and oxygen) for multiple cases. We demonstrate that this technique can be used to infer the dominant charge state of the heavy ions, despite the fact that charge is not directly measured by EIS. Using this technique, we find that the energization and dispersion of suprathermal ions during energetic particle enhancements concurrent with (or near) fast plasma flows are ordered by energy per charge state (E/q) throughout the magnetotail regions examined (~7 to 25 Earth radii). The ions with the highest energies (≳300 keV) are helium and oxygen of solar wind origin, which obtain their greater energization due to their higher charge states. Additionally, the case studies show that during these injections the flux ratio of enhancement is also well ordered by E/q. These results expand on previous results which showed that high-energy total ion measurements in the magnetosphere are dominated by high-charge-state heavy ions and that protons are often not the dominant species above ~300 keV.

Characteristics of Minor Ions and Electrons in Flux Transfer Events Observed by the Magnetospheric Multiscale Mission.

In this study, the ion composition of flux transfer events (FTEs) observed within the magnetosheath proper is examined. These FTEs were observed just upstream of the Earth's postnoon magnetopause by the National Aeronautics and Space Administration (NASA) Magnetospheric Multiscale (MMS) spacecraft constellation. The minor ion characteristics are described using energy spectrograms, flux distributions, and ion moments as the constellation encountered each FTE. In conjunction with electron data and magnetic field observations, such observations provide important contextual information on the formation, topologies, and evolution of FTEs. In particular, minor ions, when combined with the field-aligned streaming of electrons, are reliable indicators of FTE topology. The observations are also placed (i) in context of the solar wind magnetic field configuration, (ii) the connection of the sampled flux tube to the ionosphere, and (iii) the location relative to the modeled reconnection line at the magnetopause. While protons and alpha particles were often depleted within the FTEs relative to the surrounding magnetosheath plasma, the He+ and O+ populations showed clear enhancements either near the center or near the edges of the FTE, and the bulk plasma flow directions are consistent with magnetic reconnection northward of the spacecraft and convection from the dayside toward the flank magnetopause.

EMIC Waves in the Outer Magnetosphere: Observations of an Off-Equator Source Region.

Electromagnetic ion cyclotron (EMIC) waves at large L shells were observed away from the magnetic equator by the Magnetospheric MultiScale (MMS) mission nearly continuously for over four hours on 28 October 2015. During this event, the wave Poynting vector direction systematically changed from parallel to the magnetic field (toward the equator), to bidirectional, to antiparallel (away from the equator). These changes coincide with the shift in the location of the minimum in the magnetic field in the southern hemisphere from poleward to equatorward of MMS. The local plasma conditions measured with the EMIC waves also suggest that the outer magnetospheric region sampled during this event was generally unstable to EMIC wave growth. Together, these observations indicate that the bidirectionally propagating wave packets were not a result of reflection at high latitudes but that MMS passed through an off-equator EMIC wave source region associated with the local minimum in the magnetic field.

Energetic Oxygen and Sulfur Charge States in the Outer Jovian Magnetosphere: Insights From the Cassini Jupiter Flyby.

On 10 January 2001, Cassini briefly entered into the magnetosphere of Jupiter, en route to Saturn. During this excursion into the Jovian magnetosphere, the Cassini Magnetosphere Imaging Instrument/Charge-Energy-Mass Spectrometer detected oxygen and sulfur ions. While Charge-Energy-Mass Spectrometer can distinguish between oxygen and sulfur charge states directly, only 95.9 ± 2.9 keV/e ions were sampled during this interval, allowing for a long time integration of the tenuous outer magnetospheric (~200 RJ) plasma at one energy. For this brief interval for the 95.9 keV/e ions, 96% of oxygen ions were O+, with the other 4% as O2+, while 25% of the energetic sulfur ions were S+, 42% S2+, and 33% S3+. The S2+/O+ flux ratio was observed to be 0.35 (±0.06 Poisson error).

Degradation of tetraphenylphosphonium bromide at high pH and its effect on radionuclide solubility.

Recently, tetraphenylphosphonium bromide (TPPB) has been used to remove technetium from some radioactive waste streams. However, before TPPB could be approved for use it was necessary to show that TPPB and its degradation products would not have a significant detrimental effect on post-closure performance of a radioactive waste repository. TPPB is known to be stable at neutral pH, however, under alkaline conditions it degrades by an alkaline hydrolysis mechanism to triphenylphosphonium oxide (TPPO). Degradation can also occur by radiolysis to produce triphenylphosphine (TPP). The kinetics of the alkaline hydrolysis degradation of TPPB is described and the solubility of europium, iodine, nickel, technetium(VII) and uranium(VI) in aqueous solutions of TPPB and its degradation products is reported. These results were used to support the use of TPPB in removing technetium from some waste streams.

Are placental lakes of any clinical significance?

The aim of this study was to determine prospectively whether an association exists between the finding of placental lakes at the 20 week scan and an increased risk of uteroplacental complications or a poor pregnancy outcome. We studied the placental appearances in 1,198 consecutive second trimester ultrasound scans performed for routine foetal abnormality screening at our institution. The placental thickness was measured at its widest diameter in the sagittal plane and the presence or absence of placental lakes was recorded. The birth weight in each case was plotted against the centile charts in use at the hospital and recorded. Specific outcome measures included foetal growth restriction (IUGR) with a birth weight below the 5th centile, pre-eclampsia, placental abruption, and perinatal deaths. Placental lakes were seen in 17.8 per cent of the scans. There was no significant association with either maternal socio-demographic factors or perinatal mortality (OR 0.94, 95 per cent CI 0.35-2.51). No association was seen with maternal cigarette smoking (OR 1.07, 95 per cent CI 0.75-1.52), a birth weight below the 5th centile (OR 0.68, 95 per cent CI 0.39-1.18), the development of pregnancy induced hypertension (OR 0.68, 95 per cent CI 0.35-1.32), severe pre-eclampsia (OR 0.72, 95 per cent CI 0.21-2.50), or placental abruption (OR 1.79, 95 per cent CI 0.46-6.99). A finding of placental lakes was six times more likely with a thick placenta >3 cm at 20 weeks gestation (OR 6.30, 95 per cent CI 4.39 to 9.05). A finding of placental lakes during the second trimester ultrasound scan does not appear to be associated with uteroplacental complications or an adverse pregnancy outcome. The lesions are more prevalent with increasing placental thickness.

Within-subject exposure dependency in case-crossover studies.

In the case-crossover design, only cases are sampled and the hazard ratio is estimated from within-subject comparisons of exposures at the event time and in M control periods prior to the event. We consider the effect of within-subject dependence of exposures in successive time periods. We show that estimates obtained from the conditional logistic model are biased. This bias disappears if the distribution of exposures in the M+1 successive time intervals is exchangeable. In contrast, the Mantel-Haenszel estimator for the odds ratio is approximately unbiased provided that exposures are stationary. Suitable methods of analysis of case-crossover designs using maximum likelihood may be derived from cohort rather than case-control models.

Multimodal chronic pain rehabilitation program: its effect on immune function, depression, and health behaviors.

This pilot study examined the effects of a multimodal pain rehabilitation program on the immune function, self-reported pain, depression levels, and health behaviors of patients with chronic back pain. It also estimated the relationships between self-reported pain levels, immune function, depression, and health behaviors. Data were collected at week 1 (baseline) and at week 4 (last week of treatment program) on a convenience sample of 23 patients. In general, the patients' mean T lymphocyte proliferation levels showed a decline from baseline to week 4, while natural killer cell activity showed a slight increase in cell lysis. None of the findings were statistically significant. Failure to detect significant differences may be attributed to a small effect size due to the relatively small sample size. The depression levels dropped significantly during the treatment program (p = .001). Reported levels of pain and health behaviors did not significantly change. More research is needed to determine treatment effects on immune function as well as relationships between pain levels, immune function, depression, and health behaviors in this patient population.

Broken past, fragile future: personal stories of high-risk adolescent mothers.

PURPOSE: To uncover what adolescent mothers view as their childhood struggles, their transition to the role of motherhood following a childhood of abuse/neglect, and their important relationships after they became parents. DESIGN: Qualitative, phenomenological. SETTING: Community-based parenting program for first-time mothers at risk for abusing or neglecting their children. PARTICIPANTS: Seven first-time mothers, ages 13 to 20, who reported they had been abused and/or neglected as children. All had healthy newborns. RESULTS: Five themes emerged from the data: impoverished past, disintegration of relationships, emotional distance, problem fixing, and reconnecting. Participants described a process of using the experience of pregnancy and parenting as a mechanism for growth. Becoming a parent provided an opportunity to receive support from family members and to build more positive relationships. They viewed the experience as a second chance for a successful and fulfilling life.

Effects of nalmefene, CG3703, tirilazad, or dopamine on cerebral blood flow, oxygen delivery, and electroencephalographic activity after traumatic brain injury and hemorrhage.

Hemorrhage after traumatic brain injury (TBI) in cats produces significant decreases in cerebral oxygen delivery (DcereO2) and electroencephalographic (EEG) activity. To determine whether effective treatments for the separate insults of TBI and hemorrhagic shock would also prove effective after the clinically relevant combination of the two, we measured the effects of a kappa-opiate antagonist (nalmefene), an inhibitor of lipid peroxidation (tirilazad), a thyrotropin-releasing hormone analog (CG3703), a clinically useful pressor agent (dopamine) or a saline placebo on cerebral blood flow (CBF), and EEG activity after TBI and mild hemorrhagic hypotension. Cats (n = 40, 8 per group) were anesthetized with 1.6% isoflurane in N2O:O2 (70:30) and prepared for fluid-percussion TBI and microsphere measurements of CBF. Cats were randomized to receive nalmefene (1 mg/kg), tirilazad (5 mg/kg), CG3703 (2 mg/kg), dopamine (20 microg x kg(-1) x min[-1]) or a saline placebo (2 ml, 0.9% NaCl). Animals were injured (2.2 atm), hemorrhaged to 70% of preinjury blood volume, treated as just described and resuscitated with a volume of 10% hydroxyethyl starch equal to shed blood. CBF was determined and EEG activity recorded before injury, after hemorrhage, and 0, 60, and 120 min after resuscitation (R0, R60, and R120). CBF increased significantly after resuscitation (R0) in the nalmefene- and CG3703-treated groups. CBF did not differ significantly from baseline in any group at R60 or R120. DcereO2 was significantly less than baseline in the saline-, dopamine-, and tirilazad-treated groups at R60 and in the dopamine-, tirilazad-, and CG3703-treated groups at R120. EEG activity remained unchanged in the nalmefene-treated group but deteriorated significantly at R60 or R120 compared to baseline in the other groups. Nalmefene and CG3703 preserved the hyperemic response to hemodilution (otherwise antagonized by TBI), and nalmefene prevented the deterioration in DcereO2 and EEG activity that occurs after TBI and hemorrhage.

Hypertonic saline does not improve cerebral oxygen delivery after head injury and mild hemorrhage in cats.

OBJECTIVES: To investigate the effects of hypertonic saline for resuscitation after mild hemorrhagic hypotension combined with fluid-percussion traumatic brain injury. Specifically, the effects of hypertonic saline on intracranial pressure, cerebral blood flow (radioactive microsphere method), cerebral oxygen delivery (cerebral oxygen delivery = cerebral blood flow x arterial oxygen content), and electroencephalographic activity were studied. DESIGN: Randomized, controlled, intervention trial. SETTING: University laboratory. SUBJECTS: Thirty-four mongrel cats of either sex, anesthetized with 1.0% to 1.5% isoflurane in nitrous oxide/oxygen (70:30). INTERVENTIONS: Anesthetized (isoflurane) cats were prepared for traumatic brain injury, and then randomly assigned to the following groups: moderate traumatic brain injury only (2.7 +/- 0.2 atmospheres [atm], group 1); mild hemorrhage (18 mL/kg) only, followed immediately by resuscitation with 10% hydroxyethyl starch in 0.9% saline in a volume equal to shed blood (group 2); or both traumatic brain injury (2.7 +/- 0.1 atm) and mild hemorrhage, followed immediately by replacement of a volume equal to shed blood of 10% hydroxyethyl starch in 0.9% saline (group 3); or 3.0% saline (group 4). MEASUREMENTS AND MAIN RESULTS: Data were collected at baseline, at the end of hemorrhage, and at 0, 60, and 120 mins after resuscitation (or at comparable time points in group 1). Intracranial pressure in group 1 was significantly increased by traumatic brain injury at the end of hemorrhage, immediately after resuscitation, and 60 mins after resuscitation (p < .02 vs. baseline). In group 2, intracranial pressure increased significantly only immediately after resuscitation (p < .0001 vs. baseline). Groups 3 and 4 exhibited higher, although statistically insignificant, intracranial pressure increases at 60 and 120 mins after resuscitation. During resuscitation, cerebral blood flow increased significantly (p < .02 vs. baseline) in the uninjured cats. In contrast, cerebral blood flow failed to increase during resuscitation in the cats subjected to traumatic brain injury before hemorrhage and resuscitation. Although cerebral oxygen delivery in group 2 decreased significantly immediately, 60 mins, and 120 mins after resuscitation (p < .001 vs. baseline) both groups 3 and 4 had significantly lower cerebral oxygen delivery at 60 and 120 mins after resuscitation (p < .01 and p < .005, respectively, vs. group 1 at 60 mins after resuscitation, and p < .01 and p < .01, respectively, vs. group 1 at 120 mins after resuscitation). CONCLUSIONS: After a combination of hemorrhage and traumatic brain injury, neither 10% hydroxyethyl starch nor 3.0% hypertonic saline restored cerebral oxygen delivery. Although neither trauma alone nor hemorrhage alone altered electroencephalographic activity, the combination produced significant decreases in electroencephalographic activity at 60 and 120 mins after resuscitation in groups 3 and 4, suggesting that cerebral oxygen delivery is inadequately restored by either resuscitation fluid. Therefore, traumatic brain injury abolished compensatory cerebral blood flow increases to hemodilution, and neither hydroxyethyl starch nor 3.0% hypertonic saline restored cerebral blood flow, cerebral oxygen delivery, or electroencephalographic activity after hemorrhagic hypotension after traumatic brain injury.

Effects of a multimodal pain rehabilitation program: a pilot study.

The purpose of this pilot study was to examine the effects of a multimodal pain rehabilitation program on pain perceptions, opioid usage, activity, down time, sleep, and role function status of 23 chronic pain patients. Data were collected at the start of the program, at the program's completion, and again during a follow-up period (3-11 months afterwards). At the end of the program, patients reported a significant reduction in pain levels, opioid usage, and hours of disturbed sleep. During the follow-up period, patients continued to report significant improvements in activity and role functions as well as significant reductions in opioid usage, sleep disturbance, and down time. These findings provided encouraging preliminary evidence that multimodal pain rehabilitation programs for chronic pain patients may be effective in pain management and functional restoration.

The Parent-Baby Venture Program: prevention of child abuse.

TOPIC: The overwhelming obstacles adolescents face to successful achievement of the maternal role. PURPOSE: To describe an innovative, community-based program to support high risk adolescents during the early postpartum period. SOURCE: A review of the literature related to programs designed to promote maternal-role attainment and prevent child abuse/neglect. CONCLUSION: Interviews with participants indicate a positive response to the intervention but regression to maladaptive behavior in some following termination.

Effects of a community health nursing parent-baby (ad)venture program on depression and other selected maternal-child health outcomes.

This pilot study measured the effects of a community health nursing parent-baby (ad)venture program for first time mothers who were at risk for child abuse or neglect and depression. A quasi-experimental pretest-posttest design was used. Fifteen high-risk mothers in the program were compared with 15 similar mothers who received home visits from the community health nursing staff. Measures of depression, health behaviors, self-esteem, state anxiety, and maternal-infant adaptation were measured in both groups when the mothers were 4 and 16 weeks postpartum. After controlling for pretest differences, the findings showed that program mothers reported significantly higher levels of self-esteem at the three-month period than those receiving home visits (P < 0.013). In addition, over time these mothers had significantly decreased levels of depression (P < 0.009) and significantly improved their health habits (P < 0.003). Those who received home visits showed no significant changes over time.

Relaxation with guided imagery: effects on employees' psychological distress and health seeking behaviors.

1. Relaxation with guided imagery (RGI) has been successfully used for controlling acute pain, emotional distress, anxiety, and depression in a chronically ill population. Only a few studies have examined RGI as a therapeutic modality for reducing psychological distress and facilitating improvement in health behaviors. 2. The purpose of this study was to examine the effects of RGI on decreasing psychological distress and improving health seeking behaviors with a working population. 3. The practice of RGI did not significantly reduce employees' psychological distress or improve their health seeking behaviors. However, anecdotal data suggest that RGI may be useful for some individuals. 4. Because RGI is a simple, inexpensive, and non-invasive technique that most employees can do on their own, additional research efforts are needed to support its effectiveness.

Reproducibility of the short insulin tolerance test.

The short insulin tolerance test is a simple method of estimating insulin resistance by measuring the rate of fall of blood glucose following the intravenous administration of insulin. To determine its reproducibility, 18 healthy subjects underwent duplicate insulin tolerance tests separated by at least 1 week. Intravenous insulin (0.05 units kg-1) was administered into an antecubital vein and arterialized venous samples were obtained from a retrogradely cannulated vein on the dorsum of the hand on the same side. The test was terminated with an intravenous glucose injection 15 min after the administration of insulin. The mean whole blood glucose concentration fell from 4.6 mmol l-1 to 2.8 mmol l-1 while plasma insulin concentrations rose to supraphysiological levels and declined exponentially. The glucose disappearance rate (Kitt) calculated from the slope of the fall in log transformed blood glucose between 3 and 15 min after insulin injection ranged from 2.1 to 6.5 (mean 4.4) % min-1 during the first visit and 1.7 to 7.4 (mean 4.4) % min-1 during the second. The ratio of the within-subject to between-subject variance of the test was 0.24, the within-subject coefficient of variation was 13% and the between-subject coefficient of variation 26%. The short insulin tolerance test is reproducible and could be used to measure insulin resistance in large-scale epidemiological studies.

Regional cerebrovascular responses to progressive hypotension after traumatic brain injury in cats.

We investigated the effects of hypotension on cerebral blood flow (CBF) after traumatic brain injury (TBI) in cats. Isoflurane-anesthetized cats were prepared for TBI and for microsphere measurements of total (T) and regional (r) CBF. Four groups were studied: sham injury (group I, n = 6); TBI (group II, n = 6); isoflurane anesthesia, no TBI or hypotension (group III, n = 4); and isoflurane and TBI, no hypotension (group IV, n = 8). After TBI or sham trauma, mean arterial pressure (MAP) was reduced to 80, 60, and 40 mmHg by hemorrhage. Group I TCBF did not change significantly from baseline until MAP reached 40 mmHg, but rCBF was more dependent on MAP in anterior hemispheric than in brain stem regions. Group II TCBF was significantly lower than baseline, and group I TCBF at all levels of hypotension and autoregulation was impaired at higher MAP levels in anterior than in posterior brain regions. Groups III and IV indicated that decreases in TCBF were not due to duration of the preparation or to TBI in the absence of hemorrhagic hypotension. We conclude that global and regional autoregulation are absent in response to hemorrhagic hypotension after TBI.