Southern ocean carbon and heat impact on climate.

The Southern Ocean greatly contributes to the regulation of the global climate by controlling important heat and carbon exchanges between the atmosphere and the ocean. Rates of climate change on decadal timescales are therefore impacted by oceanic processes taking place in the Southern Ocean, yet too little is known about these processes. Limitations come both from the lack of observations in this extreme environment and its inherent sensitivity to intermittent processes at scales that are not well captured in current Earth system models. The Southern Ocean Carbon and Heat Impact on Climate programme was launched to address this knowledge gap, with the overall objective to understand and quantify variability of heat and carbon budgets in the Southern Ocean through an investigation of the key physical processes controlling exchanges between the atmosphere, ocean and sea ice using a combination of observational and modelling approaches. Here, we provide a brief overview of the programme, as well as a summary of some of the scientific progress achieved during its first half. Advances range from new evidence of the importance of specific processes in Southern Ocean ventilation rate (e.g. storm-induced turbulence, sea-ice meltwater fronts, wind-induced gyre circulation, dense shelf water formation and abyssal mixing) to refined descriptions of the physical changes currently ongoing in the Southern Ocean and of their link with global climate. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

Climate-driven variability of the Southern Ocean CO2 sink.

The Southern Ocean is a major sink of atmospheric CO2, but the nature and magnitude of its variability remains uncertain and debated. Estimates based on observations suggest substantial variability that is not reproduced by process-based ocean models, with increasingly divergent estimates over the past decade. We examine potential constraints on the nature and magnitude of climate-driven variability of the Southern Ocean CO2 sink from observation-based air-sea O2 fluxes. On interannual time scales, the variability in the air-sea fluxes of CO2 and O2 estimated from observations is consistent across the two species and positively correlated with the variability simulated by ocean models. Our analysis suggests that variations in ocean ventilation related to the Southern Annular Mode are responsible for this interannual variability. On decadal time scales, the existence of significant variability in the air-sea CO2 flux estimated from observations also tends to be supported by observation-based estimates of O2 flux variability. However, the large decadal variability in air-sea CO2 flux is absent from ocean models. Our analysis suggests that issues in representing the balance between the thermal and non-thermal components of the CO2 sink and/or insufficient variability in mode water formation might contribute to the lack of decadal variability in the current generation of ocean models. This article is part of a discussion meeting issue 'Heat and carbon uptake in the Southern Ocean: the state of the art and future priorities'.

Mental imagery of whole-body motion along the sagittal-anteroposterior axis.

Whole-body motor imagery is conceptualised as a mental symbolisation directly and indirectly associated with neural oscillations similar to whole-body motor execution. Motor and somatosensory activity, including vestibular activity, is a typical corticocortical substrate of body motion. Yet, it is not clear how this neural substrate is organised when participants are instructed to imagine moving their body forward or backward along the sagittal-anteroposterior axis. It is the aim of the current study to identify the fingerprint of the neural substrate by recording the cortical activity of 39 participants via a 32 electroencephalography (EEG) device. The participants were instructed to imagine moving their body forward or backward from a first-person perspective. Principal Component Analysis (i.e. PCA) applied to the neural activity of whole-body motor imagery revealed neural interconnections mirroring between forward and backward conditions: beta pre-motor and motor oscillations in the left and right hemisphere overshadowed beta parietal oscillations in forward condition, and beta parietal oscillations in the left and right hemisphere overshadowed beta pre-motor and motor oscillations in backward condition. Although functional significance needs to be discerned, beta pre-motor, motor and somatosensory oscillations might represent specific settings within the corticocortical network and provide meaningful information regarding the neural dynamics of continuous whole-body motion. It was concluded that the evoked multimodal fronto-parietal neural activity would correspond to the neural activity that could be expected if the participants were physically enacting movement of the whole-body in sagittal-anteroposterior plane as they would in their everyday environment.

Mesoscale atmosphere ocean coupling enhances the transfer of wind energy into the ocean.

Although it is well established that the large-scale wind drives much of the world's ocean circulation, the contribution of the wind energy input at mesoscales (10-200 km) remains poorly known. Here we use regional simulations with a coupled high-resolution atmosphere-ocean model of the South Atlantic, to show that mesoscale ocean features and, in particular, eddies can be energized by their thermodynamic interactions with the atmosphere. Owing to their sea-surface temperature anomalies affecting the wind field above them, the oceanic eddies in the presence of a large-scale wind gradient provide a mesoscale conduit for the transfer of energy into the ocean. Our simulations show that this pathway is responsible for up to 10% of the kinetic energy of the oceanic mesoscale eddy field in the South Atlantic. The conditions for this pathway to inject energy directly into the mesoscale prevail over much of the Southern Ocean north of the Polar Front.

Changes in Ocean Heat, Carbon Content, and Ventilation: A Review of the First Decade of GO-SHIP Global Repeat Hydrography.

Global ship-based programs, with highly accurate, full water column physical and biogeochemical observations repeated decadally since the 1970s, provide a crucial resource for documenting ocean change. The ocean, a central component of Earth's climate system, is taking up most of Earth's excess anthropogenic heat, with about 19% of this excess in the abyssal ocean beneath 2,000 m, dominated by Southern Ocean warming. The ocean also has taken up about 27% of anthropogenic carbon, resulting in acidification of the upper ocean. Increased stratification has resulted in a decline in oxygen and increase in nutrients in the Northern Hemisphere thermocline and an expansion of tropical oxygen minimum zones. Southern Hemisphere thermocline oxygen increased in the 2000s owing to stronger wind forcing and ventilation. The most recent decade of global hydrography has mapped dissolved organic carbon, a large, bioactive reservoir, for the first time and quantified its contribution to export production (∼20%) and deep-ocean oxygen utilization. Ship-based measurements also show that vertical diffusivity increases from a minimum in the thermocline to a maximum within the bottom 1,500 m, shifting our physical paradigm of the ocean's overturning circulation.

Manipulations to reduce simulator-related transient adverse health effects during simulated driving.

User comfort during simulated driving is of key importance, since reduced comfort can confound the experiment and increase dropout rates. A common comfort-affecting factor is simulator-related transient adverse health effect (SHE). In this study, we propose and evaluate methods to adapt a virtual driving scene to reduce SHEs. In contrast to the manufacturer-provided high-sensory conflict scene (high-SCS), we developed a low-sensory conflict scene (low-SCS). Twenty young, healthy participants drove in both the high-SCS and the low-SCS scene for 10 min on two different days (same time of day, randomized order). Before and after driving, participants rated SHEs by completing the Simulator Sickness Questionnaire (SSQ). During driving, several physiological parameters were recorded. After driving in the high-SCS, the SSQ score increased in average by 129.4 (122.9 %, p = 0.002) compared to an increase of 5.0 (3.4 %, p = 0.878) after driving in the low-SCS. In the low-SCS, skin conductance decreased by 13.8 % (p < 0.01) and saccade amplitudes increased by 16.1 % (p < 0.01). Results show that the investigated methods reduce SHEs in a younger population, and the low-SCS is well accepted by the users. We expect that these measures will improve user comfort.

Development and evaluation of a new instrument to measure visual exploration behavior.

Effective visual exploration is required for many activities of daily living and instruments to assess visual exploration are important for the evaluation of the visual and the oculomotor system. In this article, the development of a new instrument to measure central and peripheral target recognition is described. The measurement setup consists of a hemispherical projection which allows presenting images over a large area of ± 90° horizontal and vertical angle. In a feasibility study with 14 younger (21-49 years) and 12 older (50-78 years) test persons, 132 targets and 24 distractors were presented within naturalistic color photographs of everyday scenes at 10°, 30°, and 50° eccentricity. After the experiment, both younger and older participants reported in a questionnaire that the task is easy to understand, fun and that it measures a competence that is relevant for activities of daily living. A main result of the pilot study was that younger participants recognized more targets with smaller reaction times than older participants. The group differences were most pronounced for peripheral target detection. This test is feasible and appropriate to assess the functional field of view in younger and older adults.

Measurement of rest and activity in newborn lambs using actigraphy: studies in term and preterm lambs.

The present study used actigraphy to monitor rest-activity cycles in lambs. We employed an Actiwatch Activity Monitor, which was secured on the lamb's neck in 13 term lambs and six preterm lambs. Activity measurements began on the day of delivery and lasted for 7.3+/-0.7 days. All lambs exhibited bouts of activity, lasting from approximately 2 to 60 min, separated by periods of inactivity of about equal duration. There was a progressive increase in the frequency and intensity of activity bouts with age, and a decrease in duration. In relation to postnatal age, preterm lambs had a significantly lower frequency and intensity of activity bouts compared with term lambs and significantly longer mean active bout duration. However, in relation to post-conceptual age, preterm animals were less active at birth, but thereafter the trajectory for activity development was steeper compared with the term lambs. These differences between term and preterm lambs may be due to several factors including differences in: (1) the lengths of time the two groups spent in utero and as neonates as a proportion of the perinatal period, which could influence the rate of muscle and bone growth; (2) prenatal and postnatal hormonal profiles; and (3) maternal care. We also found differences in postnatal motility in male and female lambs, with the trajectory of activity increasing in males at Days 4-5, which could be due, in part at least, to sex differences in both prenatal and postnatal hormonal profiles.

High-latitude controls of thermocline nutrients and low latitude biological productivity.

The ocean's biological pump strips nutrients out of the surface waters and exports them into the thermocline and deep waters. If there were no return path of nutrients from deep waters, the biological pump would eventually deplete the surface waters and thermocline of nutrients; surface biological productivity would plummet. Here we make use of the combined distributions of silicic acid and nitrate to trace the main nutrient return path from deep waters by upwelling in the Southern Ocean and subsequent entrainment into subantarctic mode water. We show that the subantarctic mode water, which spreads throughout the entire Southern Hemisphere and North Atlantic Ocean, is the main source of nutrients for the thermocline. We also find that an additional return path exists in the northwest corner of the Pacific Ocean, where enhanced vertical mixing, perhaps driven by tides, brings abyssal nutrients to the surface and supplies them to the thermocline of the North Pacific. Our analysis has important implications for our understanding of large-scale controls on the nature and magnitude of low-latitude biological productivity and its sensitivity to climate change.

[Evolution of inflammatory parameters after fibroid embolization]. / Entwicklung der Entzündungsparameter nach Myomembolisation.

PURPOSE: To describe the rise of classical laboratory tests for inflammation following transarterial uterine fibroid embolization (UFE) in order to monitor the normal course following UFE. MATERIALS AND METHODS: In 20 females, white blood cell (WBC) count and C-reactive protein (CRP) were determined before and up to 5 days after UFE. With the exception of one noninflammatory complication, the post-procedure course was uneventful in all patients. The measured values were correlated with both the total uterine volume and the amount of instilled embolizing agent. RESULTS: Following UFE, an increase in the WBC count to an average maximum of 10.8 +/- 3.5/wL (range 5.9 - 18.6/wL) was found. In 13 of 20 patients, the WBC count was above normal on at least one day following UFE. The increase reached the maximum on the third post-interventional day and subsided within 5 days after the UFE. The CRP values increased significantly to an average maximum of 41.9 +/- 28.8 mg/l. The maximum was found on the 2nd post-interventional day in 8 patients, on the 3rd day in 11 patients and on the 4th day in one patient. No correlation to the total uterine volume or to the amount of the instilled embolizing agents was detected. CONCLUSION: Following uncomplicated UFE, a steep increase in CRP occurs with no or only a mild increase in the WBC count, which does not indicate an infected fibroid. The maximum is reached on the 3rd or 4th post-interventional day, followed by a decline in CRP and normalization of the WBC count.

Fetal behavioural state changes following maternal fluoxetine infusion in sheep.

Clinical depression is diagnosed in 5-15% of women during pregnancy, increasing the risk of negative outcomes. Fluoxetine (FX), a selective serotonin reuptake inhibitor, is prescribed during pregnancy. In adults, FX alters sleep patterns with single doses decreasing total sleep time and rapid eye movement sleep. The effects of FX on sleep in the fetus are unknown. However, 5-hydroxytryptophan, the precursor of serotonin, has been reported to prolong high-voltage (HV) electrocortical (ECoG) activity and increase the incidence of fetal breathing movements (FBM) in the sheep fetus. We hypothesize that FX exposure will decrease the incidence of LV ECoG in the fetus. Twenty-one pregnant sheep were surgically prepared for chronic study of blood gases, ECoG activity, eye movements and FBM. After 3 days of recovery, ewes received a 70-mg bolus i.v. infusion of FX or sterile water followed by continuous infusion at a rate of 0.036 mg/min for 8 days. The incidence of low-voltage (LV) ECoG decreased from 54+/-4% on the preinfusion day to 45+/-5% on infusion day 1 in the FX group and remained decreased throughout the infusion period. In addition, the incidence of both eye movements and FBM was decreased on infusion day 1 compared to preinfusion day in the FX group. HV ECoG increased from 39+/-3% on preinfusion day to 68+/-14% on FX infusion day 1 and remained elevated throughout the infusion period. These data show that maternal FX administration alters fetal behavioural state.

The global carbon cycle: a test of our knowledge of earth as a system.

Motivated by the rapid increase in atmospheric CO2 due to human activities since the Industrial Revolution, several international scientific research programs have analyzed the role of individual components of the Earth system in the global carbon cycle. Our knowledge of the carbon cycle within the oceans, terrestrial ecosystems, and the atmosphere is sufficiently extensive to permit us to conclude that although natural processes can potentially slow the rate of increase in atmospheric CO2, there is no natural "savior" waiting to assimilate all the anthropogenically produced CO2 in the coming century. Our knowledge is insufficient to describe the interactions between the components of the Earth system and the relationship between the carbon cycle and other biogeochemical and climatological processes. Overcoming this limitation requires a systems approach.

ECT in mixed affective states: a case series.

There is limited information regarding the effectiveness of electroconvulsive therapy (ECT) as a treatment for patients in a mixed affective state. The authors report their experience using this treatment in medication-resistant patients meeting Research Diagnostic Criteria (RDC) for both mania and major depression. Clinical and response characteristics of these patients are described. Forty-one consecutively admitted patients meeting the RDC for mania received pharmacotherapy. Eight patients failing to respond to pharmacotherapy were referred for ECT, and seven consented. All met RDC for both mania and major depressive disorder. All patients receiving ECT remitted. The patient who did not accept ECT did not improve and ultimately needed transfer to a state hospital for longer term care. Mixed manic-depressive states are responsive to ECT, even in medication-refractory patients.

A comparison of the clock drawing test and the Pfeiffer Short Portable Mental Status Questionnaire in a geropsychiatry clinic.

Wolf-Klein and colleagues' clock drawing test (CDT) performance was compared with Pfeiffer's Short Portable Mental Status Questionnaire (Pfeiffer) scores in 145 outpatient geropsychiatry patients. Although normal CDT results were almost always associated with normal Pfeiffer scores, 21% of Pfeiffer normal individuals drew abnormal clocks. Age, but not gender or education, was significantly associated with this finding. Almost all the Pfeiffer normal subjects who drew abnormal clocks were diagnosed with primary psychiatric disorders (85%) or neurologically based organic mood and anxiety disorders (12%); only one (3%) had dementia. We suggest the discrepant performance between the CDT and Pfeiffer may result from psychiatric illness. Contributing to this may be CDT sensitivity to executive skills dysfunction. This dyscontrol can occur in patients with dementia and other neurological disorders, but also presents in some primary mental disorders. Older age may heighten this impairment. In a typical geropsychiatry clinic, the CDT will not have high specificity for Alzheimer's disease as reported by Wolf-Klein and her colleagues. This results from the presence of many patients with primary psychopathology, some of whom will draw abnormal clocks, and a limited number with dementia-particularly Alzheimer's disease. Abnormal CDT results of geropsychiatry outpatients must therefore be interpreted carefully. Additional conclusions regarding the study results are discussed.

The evolution of a faculty development program in an academic psychiatry department.

Issues affecting faculty development in academic psychiatry departments have taken on a special urgency as a result of declining financial support from government sources and the emerging consequences of this country's fast-evolving health care system. Junior faculty need usable information on how to succeed in academia. Available information from the senior administration ("top-dawn") often lacks the immediacy and accessibility of grassroots ("bottom-up") strategies that more experienced junior colleagues have discovered. Over the past 2 years, the Department of Psychiatry at the University of Texas-Houston Health Science Center has focused attention on codifying these grassroots efforts and on integrating them with formal departmental initiatives. The authors describe how general recommendations formulated by departmental planning committees and a Continuous Quality Improvement Team on faculty development were developed into a formal, concrete program f or career development. (Academic Psychiatry 1997; 21:107-115).

The origin of IgG production and homogeneous IgG components after allogeneic bone marrow transplantation.

Pediatric recipients (n = 25) of an allogeneic bone marrow (BM) graft were selected on the basis of informative IgG allotype (Gm) differences between the BM donor and the recipient. To investigate the kinetics of the appearance of IgG of donor origin and the disappearance of IgG of recipient origin, G1m and G2m allotype levels were quantified in sera obtained at regular intervals between 3 months and 5 years after BM transplantation (BMT). For this quantification, a dot immunobinding assay (DIBA) has been developed. In 19 of 22 informative recipients, the Gm allotype distribution had reached the range of values expected on the basis of the Gm phenotype of the donor within 6 months after BMT. Remarkably, IgG of recipient origin persisted in 15 of 18 informative recipients until last follow up, ie, for several years after BMT. In addition to the origin of total IgG production, the origin of homogeneous IgG components (H-IgG) appearing after BMT was investigated. H-IgG of donor origin could be detected as early as 3 weeks after BMT, but also H-IgG of recipient origin were present in 8 of 13 informative recipients for a period of up to 1 year after BMT. We conclude that host-type IgG-producing cells were not eradicated by the (myeloablative) conditioning regimen and persisted in a high number of graft recipients. It is our hypothesis that lack of graft-versus-host disease (GVHD) in the majority of these recipients results in the persistence of IgG-producing cells of host origin. These observations may be relevant for the evaluation of patients who received allogeneic BMT for the treatment of multiple myeloma.

Drug treatment of Alzheimer's disease. Effects on caregiver burden and patient quality of life.

Alzheimer's disease is a devastating illness that will become more common as the population ages. Although clinical diagnosis of the illness is not certain without histological examination of the brain, and misdiagnosis may occur, broad working criteria to help diagnose the likely presence of Alzheimer's disease are available. Thoughtful clinical evaluation improves diagnostic accuracy, and appropriately diagnosed patients are critical for involvement in research into new antidementia agents. Essential to the discovery of new drugs is careful measurement of illness response. A variety of scales--some aimed at patients, others at their caregivers, and yet others for clinicians--assess Alzheimer's disease severity, progression, symptom response, and quality of life. Of note, patient response is not the only measurement of treatment benefit today. Growing interest is also being placed on tracking the possible amelioration of caregiver 'burden'. This burden refers to the psychological, physical, and material costs of providing care for an Alzheimer's patient over long periods of time. A number of scales and questionnaires have been developed and are occasionally used. Many drugs have been tried in Alzheimer's disease, but very few have produced any benefit, and this is often modest. Ergoloid mesylates, initially thought to be effective, are now considered of little value. The cholinomimetic drugs, especially the acetylcholinesterase inhibitor tacrine, have provided a very modest benefit, slowing the progression of the illness for a number of months. No cognitive improvement has been noted with the various nootropic agents such as piracetam. Early studies with levacecarnine (acetyl-L-carnitine), a substance that facilitates the use of fatty acids, memantidine, the dimethyl derivative of amantidine, and the calcium channel blocker nimodipine, have shown some promise, but require larger, more rigorous studies. As mentioned above, documenting effects in individual patients is crucial; examining for potential benefit to caregivers is a growing part of research design. Current treatment efforts will become more sophisticated as a deeper understanding of the neurobiology of Alzheimer's disease develops. For the immediate future, the goal is not cure but slowing of the disease process. Achieving this limited goal would have a substantial impact on the financial and human costs of the illness.