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A unique gradient furnace for directional solidification experiments with bulk Al-alloy samples developed at German Aerospace Center is presented. It allows for in situ process control in solidifying samples by using x-radiography, and further insight into the solidification process is gained in combination with x-ray computational tomography on the solidified samples. Tracking of interfaces during directional solidification of bulk samples via in situ x-radiography (TIREX) enables the investigation of the melting process and observation of the movement of the entire mushy zone through the sample, tracing the solid-liquid interface during directional solidification and correlating the observations with the microstructure of the samples. Monitoring the temperature profile inside the sample by in situ observation of the length of the mushy zone is particularly important because the temperature gradient G and the rate of interfacial growth v determine the microstructure of solidification. The x-radiography setup offers temporal and spatial resolutions of 0.5 s and 70 µm, respectively, with a field of view of 10 × 50 mm2. Constant solidification velocities of up to 0.15 mm s-1 at a temperature gradient of up to 8 K mm-1 can be achieved in a temperature range of 537-1373 K. A flat solid-liquid interface inside a rod-like sample with 5 mm diameter is achieved by surrounding the sample by thermal isolating graphite foam. Performance tests with hypoeutectic Al-10 wt. % Cu alloy samples show the functionality of the furnace facility.

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Multicellular organisms typically develop from a single fertilized egg and therefore consist of clonal cells. We report an extraordinary reproductive system in the yellow crazy ant. Males are chimeras of haploid cells from two divergent lineages: R and W. R cells are overrepresented in the males' somatic tissues, whereas W cells are overrepresented in their sperm. Chimerism occurs when parental nuclei bypass syngamy and divide separately within the same egg. When syngamy takes place, the diploid offspring either develops into a queen when the oocyte is fertilized by an R sperm or into a worker when fertilized by a W sperm. This study reveals a mode of reproduction that may be associated with a conflict between lineages to preferentially enter the germ line.

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We describe a highly integrated automated experiment module that allows us to investigate the active Brownian motion of light-driven colloidal Janus-particle suspensions. The module RAMSES (RAndom Motion of SElf-propelled particles in Space) is designed for the sounding rocket platform MAPHEUS (MAterialPHysikalische Experimente Unter Schwerelosigkeit). It allows us to perform experiments under weightlessness conditions in order to avoid sedimentation of the Janus particles and thus to study the spatially three-dimensional dynamics in the suspension. The module implements a newly developed strong homogeneous light source to excite self-propulsion in the Janus particles. The light source is realized through an array of high-power light-emitting diodes and replaces the conventional laser source, thus reducing heat dissipation and spatial extension of the experiment setup. The rocket module contains ten independent sample cells in order to ease the systematic study of the effect of control parameters such as light intensity or particle concentration and size in a single sounding-rocket flight. For each sample cell, transmitted light intensities are stored for postflight analysis in terms of differential dynamical microscopy.

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A compact fully protected microfocus X-radiography facility (XRISE-M) is presented for the study of microstructure evolution during the solidification of thin liquid alloy samples and chemical diffusion in liquid binary alloys in situ and in real-time aboard a sounding rocket. XRISE-M presently enables the simultaneous processing of either two near-isothermal solidification furnaces or a combination of a linear-shear cell diffusion furnace and a near-isothermal solidification furnace. For optimal detector calibration shortly before flight, the furnaces can be rotated around the central beam axis and calibration images can be recorded. The facility allows preheating the samples into the liquid state prior to lift-off without leakage during the ascent phase at accelerations of up to 27 g. Macrosegregation on remelting of thin metal samples for microstructure evolution investigations is prevented by an inclinable furnace metric. The use of ion-getter pumps for vacuum generation enables us to exploit the entire available time of reduced gravity for image recording and data acquisition. With the device and currently available sample environments, microstructure formation upon solidification and chemical diffusion under purely diffusive conditions in alloys can be investigated. The facility can be used equally for other investigations such as granular matter dynamics or metal foaming, provided that suitable experiment inserts are developed in the future.

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Perioperative pain reduction, particularly during the first two days, is highly important for patients after total knee arthroplasty (TKA). Problems are not only caused by medical issues but by organization and hospital structure. The present study shows how the quality of pain management can be increased by implementing a standardized pain concept and simple, consistent benchmarking. All patients included into the study had undergone total knee arthroplasty. Outcome parameters were analyzed by means of a questionnaire on the first postoperative day. A multidisciplinary team implemented a regular procedure of data analyzes and external benchmarking by participating in a nationwide quality improvement project. At the beginning of the study, our hospital ranked 16th in terms of activity-related pain and 9th in patient satisfaction among 47 anonymized hospitals participating in the benchmarking project. At the end of the study, we had improved to 1st activity-related pain and to 2nd in patient satisfaction. Although benchmarking started and finished with the same standardized pain management concept, results were initially pure. Beside pharmacological treatment, interdisciplinary teamwork and benchmarking with direct feedback mechanisms are also very important for decreasing postoperative pain and for increasing patient satisfaction after TKA.

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OBJECTIVE: To evaluate whether a further optimization of an existing accelerated clinical pathway protocol after total knee replacement is feasible and improves postoperative outcome. DESIGN: Prospective, parallel group design. SETTING: Orthopaedic University Medical Centre. PATIENTS: A total of 143 patients, scheduled for unilateral primary total knee replacement under perioperative regional analgesia. INTERVENTION: Sixty-seven patients received an optimized accelerated clinical pathway including patient-controlled regional analgesia pumps, ultra-early/doubled physiotherapy and motor-driven continuous passive motion machine units. Seventy-six patients received a standard accelerated clinical pathway. MAIN MEASURES: Feasibility was defined as the proportion of patients successfully completing the assigned pathway. Early postoperative pain on a visual analogue scale, consumption of regional anaesthetics, knee range of motion, time out of bed, non-stop walking distance/stair climbing, circumference measurement and Knee Society Score on the operated leg. Possible discharge according to an own discharge checklist. RESULTS: All patients assigned to both groups successfully completed this pathway. Patients in the optimized pathway showed significant benefits regarding stair climbing/walking distance/time out of bed/circumference measurements of the thigh/Knee Society function score on the fifth postoperative day and stair climbing/ circumference measurements of the thigh on the eighth postoperative day, and reduction of the consumption of regional anaesthetics. No significant reduction in length of stay was observed. CONCLUSIONS: Early postoperative functional process indicators tended to be higher within the optimized pathway group, but the main effects flattened over the course of the first eight postoperative days.

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BACKGROUND: Cerebral infarction after aneurysmal subarachnoid haemorrhage (SAH) is presumed to be due to cerebral vasospasm, defined as arterial lumen narrowing from days 3 to 14. METHODS: We reviewed the computed tomography scans of 103 patients with aneurysmal SAH for radiographic cerebral infarction and controlled for other predictors of outcome. A blinded neuroradiologist reviewed the angiograms. Cerebral infarction from vasospasm was judged to be unlikely if it was visible on computed tomography within 2 calendar days of SAH or if angiography showed no vasospasm in a referable vessel, or both. RESULTS: Cerebral infarction occurred in 29 (28%) of 103 patients with SAH. 18 patients had cerebral infarction that was unlikely to be due to vasospasm because it was visible on computed tomography by day 2 (6 (33%)) or because angiography showed no vasospasm in a referable artery (7 (39%)), or both (5 (28%)). In a multivariate model, cerebral infarction was significantly related to World Federation of Neurologic Surgeons grade (odds ratio (OR) 1.5/grade, 95% confidence interval (CI) 1.1 to 2.01, p = 0.006) and SAH-Physiologic Derangement Score (PDS) >2 (OR 3.7, 95% CI 1.4 to 9.8, p = 0.01) on admission. Global cerebral oedema (OR 4.3, 95% CI 1.5 to 12.5, p = 0.007) predicted cerebral infarction. Patients with cerebral infarction detectable by day 2 had a higher SAH-PDS than patients with later cerebral infarction (p = 0.025). CONCLUSIONS: Many cerebral infarctions after SAH are unlikely to be caused by vasospasm because they occur too soon after SAH or because angiography shows no vasospasm in a referable artery, or both. Physiological derangement and cerebral oedema may be worthwhile targets for intervention to decrease the occurrence and clinical impact of cerebral infarction after SAH.

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BACKGROUND: To describe the use of pumpless extracorporeal interventional lung assist (iLA) for transportation of patients with severe life-threatening acute lung failure from tertiary hospitals to a specialized centre. METHODS: Retrospective analysis in eight patients with severe lung failure requiring interhospital transport, in whom implementation of an iLA system at a tertiary hospital for air/ground transportation was performed. RESULTS: After implementation of iLA, a rapid increase in CO2-elimination (Pa(CO2) before iLA: 8.92+/-2.9 kPa, immediately after implementation: 5.06+/-0.93 kPa, 24 h after implementation: 4.53+/-1.20 kPa [mean+/-SD], P<0.05) was observed and a significant improvement in oxygenation (Pa(O2) before iLA: 6.66+/-2.26 kPa, immediately after implementation: 10.39+/-3.33 kPa, 24 h after implementation: 10.25+/-5.46 kPa, P<0.05) was noted. During transport, no severe complications occurred. Four patients died during further treatment due to multiple trauma or multiple organ failure. CONCLUSIONS: Due to ease of handling, high effectiveness and relatively low costs, iLA seems to be a useful system for treatment and transportation of patients with severe acute lung injury or ARDS suffering from life-threatening hypoxia and/or hypercapnia.

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BACKGROUND: It is well known that space travel cause post-flight orthostatic hypotension and it was assumed that autonomic cardiovascular control deteriorates in space. Lower body negative pressure (LBNP) was used to assess autonomic function of the cardiovascular system. METHODS: LBNP tests were performed on six crew-members before and on the first days post-flight in a series of three space missions. Additionally, two of the subjects performed LBNP tests in-flight. LBNP mimics fluid distribution of upright posture in a gravity independent way. It causes an artificial sequestration of blood, reduces preload, and filtrates plasma into the lower part of the body. Fluid distribution was assessed by bioelectrical impedance and anthropometric measurements. RESULTS: Heart rate, blood pressure, and total peripheral resistance increased significantly during LBNP experiments in-flight. The decrease in stroke volume, the increased pooling of blood, and the increased filtration of plasma into the lower limbs during LBNP indicated that a plasma volume reduction and a deficit of the interstitial volume of lower limbs rather than a change in cardiovascular control was responsible for the in-flight response. Post-flight LBNP showed no signs of cardiovascular deterioration. The still more pronounced haemodynamic changes during LBNP reflected the expected behaviour of cardiovascular control faced with less intravascular volume. In-flight, the status of an intra-and extravascular fluid deficit increases sympathetic activity, the release of vasoactive substances and consequently blood pressure. Post-flight, blood pressure decreases significantly below pre-flight values after restoration of volume deficits. CONCLUSION: We conclude that the cardiovascular changes in-flight are a consequence of a fluid deficit rather than a consequence of changes in autonomic signal processing.

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We studied three Russian cosmonauts to better understand how long-term exposure to microgravity affects autonomic cardiovascular control. We recorded the electrocardiogram, finger photoplethysmographic pressure, and respiratory flow before, during, and after two 9-mo missions to the Russian space station Mir. Measurements were made during four modes of breathing: 1) uncontrolled spontaneous breathing; 2) stepwise breathing at six different frequencies; 3) fixed-frequency breathing; and 4) random-frequency breathing. R wave-to-R wave (R-R) interval standard deviations decreased in all and respiratory frequency R-R interval spectral power decreased in two cosmonauts in space. Two weeks after the cosmonauts returned to Earth, R-R interval spectral power was decreased, and systolic pressure spectral power was increased in all. The transfer function between systolic pressures and R-R intervals was reduced in-flight, was reduced further the day after landing, and had not returned to preflight levels by 14 days after landing. Our results suggest that long-duration spaceflight reduces vagal-cardiac nerve traffic and decreases vagal baroreflex gain and that these changes may persist as long as 2 wk after return to Earth.

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Seventy-nine heart transplant recipients were vaccinated with a trivalent influenza virus vaccine 1996/97 containing the strains A/Singapore/6/86 (H1N1), A/Wuhan/395/95 (H3N2), and B/Beijing/184/93. The proportions of patients with protective levels of antibody (HI > or = 40) after vaccination ranged from 100% (A/Singapore [H1N1]) to 31.6% (B/Beijing) and their mean fold titer increases were lower than those recorded for vaccination of 109 healthy subjects with the same batch of vaccine. The vaccinations were tolerated well and did not result in serious side effects, such as graft rejections. Our findings indicate that influenza vaccination can induce protective antibody levels in a substantial proportion of heart transplant recipients and lend support to the recommendation to vaccinate such patients annually against influenza.

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Following an outbreak of hepatitis B virus (HBV) infection amongst immunosuppressed transplant recipients, the complete sequences of the HBV-DNA isolated from nine of the affected patients were determined. The DNA sequences were found to differ from each other by a maximum of three nucleotides and belonged to the same serotype (ayw3). By contrast, the sequences differed by 18 nucleotides from the most similar HBV-DNA sequence published, indicating a common source of infection. The infection chains that have been constructed according to the base differences between the DNAs agreed well with those previously established on the basis of epidemiological data [Drescher et al. (1994) Journal of Hospital Infection 26:81-92]. At least two HBV populations, differing by one or two nucleotides, were detected in four patients, and coexisted for differing periods of time. Mutations of the core and X-peptide were not found. The data were used to calculate evolution rates of HBV DNA, both for HBV persisting within a patient and for infection chains. The rates obtained were of the same order as described previously for immunocompetent patients, indicating that the immunosuppressive medication did not influence the evolution rate. However, the evolution rate was found to decrease with increasing evolution time.

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The long-term acclimation of cardiac rhythms to microgravity was studied in four astronauts aboard the Russian space station MIR during wakefulness and sleep. Sleep polygraphies were obtained between the third and the 30th day in space and, in addition, prior to mission on the ground. From each of the sleep polygraphies, beat-to-beat intervals of cardiac rhythms were determined. The response of heart period and heart period variability to the stimulus microgravity was tested during sleep across sleep stages and during waking. A lengthening of heart period by about 100 ms was found in space compared to measurements on the ground. The slowing of heart rate was more pronounced for non-REM sleep than for REM sleep. A systematic change in heart period in relation to the duration of the stay in space could not be detected. An analysis of heart period variability in the high frequency (respiratory sinus arrhythmia) band supports the hypothesis that the decrease of heart rate under microgravity is produced by an increase in parasympathetic activity. Testing the response of cardiac rhythms to microgravity across distinct behavioural states seems to be a powerful tool to investigate the cardiovascular system.

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For influenza H1N1 strains, including some of their escape variants, the association of amino acid differences located at their hemagglutinin HA1 domains with their antigenic relationship was examined. The antigenic relationship was recorded in terms of the ratios of hemagglutination inhibition (HI) titers, the concentration of antibody molecules recognized by the virus, and the equilibrium constant of epitope-paratope interaction determined with heterologous virus compared to that found with homologous virus. The HI titers of antisera were found to depend primarily on the concentration of antibody molecules recognized by the virus and much less on the equilibrium constants. The avidity of antibody in sera raised against historically later strains with earlier strains was higher than vice versa. In contrast to the results obtained with antisera, the same concentration of monoclonal antibody directed to the Sb site of A/Brazil virus was recognized by both heterologous and homologous viruses, and the differences in HI titers observed were due to avidity changes only. Some of the amino acid differences located at each of the antigenic sites were found to be associated with a reduction in the HI titers and in the concentration of antibody molecules recognized by heterologous virus, whereas other differences in addition decreased the avidity of epitope-paratope interaction. Further amino acid differences decreased the avidity only. The strains tested differed also in their amino acids located outside the antigenic sites. However, an influence of these differences on the reaction of virus with antibody could not be evidenced. For the strains tested, the antigenic hemagglutinin drift occurred by reduction of the concentration of antibody molecules recognized by the virus and by avidity changes, which, in turn, were caused by exchanges of some key residues located at the antigenic sites.

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A comprehensive analysis of cardiovascular control (CVC) patterns with multiple subjects is presented. It became feasible by recent methodological advances. Simple computer models were generated automatically, reproducing only factors of the true model that are relevant to the focus if investigation. These models--named aspect-models--could in turn be used in model individualization, thus reducing the necessary computational amount. The achieved speedup by a factor of more than three thousand and the high numerical stability of the resulting method allows the unsupervised identification of a large body of experimental data. The analysis of tilt table experiments of 18 subjects revealed a remarkable variety of reaction patterns. Closer examination yielded different classes of subjects. Two main groups corresponding to basic types of CVC were observed. Three outliers could be assigned to the specific situation of some subjects.

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Reparative therapy has come to generically define talking cures that claim to change an individual's homosexual orientation to a heterosexual one. Although other treatment modalities have also promised to "cure" homosexuality, the history of reparative therapies has become inexorably linked with that of psychoanalysis. This paper reviews the history and theoretical assumptions of psychoanalytically-oriented practitioners, beginning with Freud's juvenilization of gay people to the later analysts who pathologized and attempted to change same-sex attractions. The evolution of reparative therapists from medically concerned practitioners into antigay political activists is also discussed. The evolution of one branch of psychoanalytic theory into an antihomosexual political movement illustrates the permeability of boundaries between clinical issues and political ones. In their open support of antigay legislation, reparative therapists have moved from the traditional psychoanalytic center and have been embraced by conservative religious and political forces opposed to homosexuality. In doing so, they have apparently adopted religious organizational practices themselves, preaching dogma and stifling dissent. The increasing marginalization of reparative therapists from the psychoanalytic mainstream illustrates how psychoanalysis per se is neither gay-affirming nor condemning, although psychoanalytic practitioners may fall into either of these categories.

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