Quantum Limits of Stochastic Cooling of a Bosonic Gas

The quantum limits of stochastic cooling of trapped atoms are studied. The energy subtraction due to the applied feedback is shown to contain an additional noise term due to atom-number fluctuations in the feedback region. This novel effect is shown to dominate the cooling efficiency near the condensation point. Furthermore, we show first results that indicate that Bose--Einstein condensation could be reached via stochastic cooling.Comment: 5 pages, 3 figures, to appear in Phys. Rev.

Spinor condensates and light scattering from Bose-Einstein condensates

These notes discuss two aspects of the physics of atomic Bose-Einstein condensates: optical properties and spinor condensates. The first topic includes light scattering experiments which probe the excitations of a condensate in both the free-particle and phonon regime. At higher light intensity, a new form of superradiance and phase-coherent matter wave amplification were observed. We also discuss properties of spinor condensates and describe studies of ground--state spin domain structures and dynamical studies which revealed metastable excited states and quantum tunneling.Comment: 58 pages, 33 figures, to appear in Proceedings of Les Houches 1999 Summer School, Session LXXI

For reproductive justice in an era of Gates and Modi – the violence of India’s population policies

This article addresses India’s contemporary population control policies and practices as a form of gendered violence perpetrated by the state and transnational actors, arguing that the targeting of poor, Adivasi and Dalit women for coercive mass sterilizations and unsafe injectable and implantable contraceptives is made possible by the long-term construction of particular women’s lives as devalued and disposable, and of their bodies as excessively fertile and therefore inimical to development and progress. It further considers how population policy is currently embedded in the neoliberal framework of development being pursued by the Indian state. In particular, it argues that the violence of population policies is being deepened as a result of three central and interrelated aspects of this framework: corporate dispossession and displacement, the intensification and extension of women’s labour for global capital, and the discourses and embodied practices of Hindu supremacism. At the same time, India’s population policies cannot be understood in isolation from the global population control establishment, which is increasingly corporate led, and from broader structures of racialised global capital accumulation. The gendered violence of India’s contemporary population policies and the practices they produce operates at several different scales, all of which involve the construction of certain bodies as ‘unfit’ to reproduce and requiring intervention and control

Inter-hemispherical asymmetry in default-mode functional connectivity and BAIAP2 gene are associated with anger expression in ADHD adults

Attention deficit hyperactivity disorder (ADHD) is accompanied by resting-state alterations, including abnormal activity, connectivity and asymmetry of the default-mode network (DMN). Concurrently, recent studies suggested a link between ADHD and the presence of polymorphisms within the gene BAIAP2 (i.e., brain-specific angiogenesis inhibitor 1-associated protein 2), known to be differentially expressed in brain hemispheres. The clinical and neuroimaging correlates of this polymorphism are still unknown. We investigated the association between BAIAP2 polymorphisms and DMN functional connectivity (FC) asymmetry as well as behavioral measures in ADHD adults. Resting-state fMRI was acquired from 30 ADHD and 15 healthy adults. For each subject, rs7210438 and rs8079626 within the gene BAIAP2 were genotyped. ADHD severity, impulsiveness and anger were assessed for the ADHD group. Using multivariate analysis of variance, we found that genetic features do have an impact on DMN FC asymmetry. In particular, polymorphism rs8079626 affects medial frontal gyrus and inferior parietal lobule connectivity asymmetry, lower for AA than AG/GG carriers. Further, when combining FC asymmetry and the presence of the rs8079626 variant, we successfully predicted increased externalization of anger in ADHD. In conclusion, a complex interplay between genetic vulnerability and inter-hemispherical DMN FC asymmetry plays a role in emotion regulation in adult ADHD

Studies of nuclear-waste migration in geologic media. Annual report, November 1976--October 1977

The confinement of nuclear wastes in geologic formations is being considered as a method of permanently disposing of the waste. Laboratory experiments (column infiltration, static absorption, and batch partitioning experiments) were performed with nuclides of Cs, Pu, Np, and Am to examine the migratory characteristics of long-lived radionuclides that could be mobilized by groundwaters infiltrating a nuclear waste repository and the surrounding geologic body. In column infiltration experiments, the positions of peak concentrations of Cs in chalk or shale columns; Pu in limestone; Am in limestone, sandstone, or tuff; and Np in a limestone column did not move when the columns were infiltrated with water. However, fractions of each of the nuclides were seen downstream from the peaks, indicating that there was a large dispersion in the relative migration rates of each of the trace elements in the lithic materials studied. The results of static absorption experiments indicate that Pu and Am are strongly absorbed from solution by the common rocks studied and that their migration relative to ground-water flow is thereby retarded. In addition, the reaction rates of dissolved nuclides with rocks were found to vary considerably in different rock-element systems. Batch partitioning experiments were performed to test whether absorption processes are reversible. After granulated basalt and americium-bearing water were contacted in an absorption step, part of the water was replaced with water free of Am and the Am repartitioned between rock and solution. The distribution of Am after desorption was comparable to its distribution after absorption. In cntrast, when tablets of various rocks were allowed to dry between absorption and desorption tests, Pu and Am were not generally desorbed from the tablets. This suggests that reversible reactions of nuclides, between waters and rocks may be upset by treatments such as drying

Analytical measurements of actinide migration in a laboratory-simulated basalt HLW repository

Described are the analytical methods and results used to determine the migration of actinides in a flowing-groundwater laboratory-simulation of a basalt repository for high-level nuclear waste. The radiochemical methods developed and employed to measure actinide activities in groundwater samples and component surfaces include the use of gamma, X-rays, and alpha spectroscopy, with associated preparation and calibration. These methods include double isotope spiking with Np-235 and Pu-236 for determination of Np-237 and Pu-239 in groundwater, gamma-spectroscopic measurements of rock surfaces for spatially profiling neptunium activity, and a leaching procedure for quantitating the actinide activities on those rock surfaces

Interaction of groundwater and fresh basalt fissure surfaces and its effect on the migration of actinides

Experiments are being performed at Argonne National Laboratory (ANL): (1) to identify interactions of radionuclides and repository components that effect nuclide migration, and (2) to assess changes in nuclide migration caused by modifications expected upon aging of the waste, clay backfill, and rock. The experiments are conducted with radioactive borosilicate glass, bentonite and mechanically fissured basalt rock in flowing water analogous to their configuration in a breach of a nuclear waste repository. Changes undergone by the groundwater as it passed through the fissure include: (1) drop in pH from 10 to 8, (2) loss of suspended particulate, and (3) loss of dissolved/suspended U, Np, and Pu. These effects, also studied as functions of radiation dose and of laboratory aging of the repository components, are related to the predicted long-term performance of a nuclear waste repository

Kidney function and markers of inflammation in elderly persons without chronic kidney disease: The health, aging, and body composition study

Inflammatory markers are elevated in persons with estimated glomerular filtration rates less than 60ml/min/1.73m2. As cystatin C may detect small changes in kidney function not detected by estimated glomerular filtration rate, we evaluated the association between cystatin C and serum markers of inflammation in older adults with estimated glomerular filtration rate ≥60. This is an analysis using measures from the Health, Aging, and Body Composition Study, a cohort of well-functioning adults aged 70–79 years. Cystatin C correlated with all five inflammatory biomarkers: C-reactive protein (r=0.08), interleukin-6 (r=0.19), tumor necrosis factor α (TNF-α) (r=0.41), soluble TNF receptor 1 (STNF-R1) (r=0.61), and soluble TNF receptor 2 (STNF-R2) (r=0.54); P<0.0005 for all. In adjusted analyses, cystatin C concentrations appeared to have stronger associations with each biomarker compared with estimated glomerular filtration rate or serum creatinine. Participants with a cystatin C≥1.0mg/l had significantly higher levels of all five biomarkers compared to those with a cystatin C<1.0 (mean differences ranging 16–29%, all P<0.05). Cystatin C has a linear association with inflammatory biomarkers in an ambulatory elderly cohort with estimated glomerular filtration rates ≥60; associations are particularly strong with TNF-α and the STNF-R