Diaspora

In the year 722 bce, Israel was destroyed by Assyria and the people fled to Judah, where they came to be known as Jews. When the history of this movement was written down between 640 and 610 bce, it was decreed of the Jewish people that ‘thou shalt be a diaspora in all kingdoms of the earth’ (Deuteronomy, 28:25). From these very specifically Jewish origins, the term has spread to describe the general experience of large-scale geographical dispersion of human populations from a shared home place as a result of violent and traumatic events. So, the scattering of Greeks after the fall of Constantinople (1453), of Armenians after the First World War, or of Africans as a result of the transatlantic slave trade are all seen as archetypal diasporas

Diaspora and development

This chapter describes how diaspora has been applied to development practice since the 1990s. It also provides a more critical analysis of four conceptual terrains where diaspora and development have been brought together: modernization, time/space, belonging/identity and securitization/financialization. The chapter also describes the institutions and activities of the international development industry in relation to the ambition to enrol diasporas in development. It shows how a series of governmental and non-governmental actors have identified specific goals and roles in a process of steering diasporas towards contributing to international development. The chapter also argues that in a matter of a few decades the idea of diasporas being part of the development process has moved from the periphery to the mainstream, largely driven by an interest in remittances. It suggests that a focus on diaspora brings broad claims about the securitization and financialization of development into sharp empirical focus

The Anisotropy in the Cosmic Microwave Background At Degree Angular Scales

We detect anisotropy in the cosmic microwave background (CMB) at degree angular scales and confirm a previous detection reported by Wollack et al. (1993). The root-mean-squared amplitude of the fluctuations is $44^{+13}_{-7} \mu$K. This may be expressed as the square root of the angular power spectrum in a band of multipoles between $l_{eff}=69^{+29}_{-22}$. We find $\delta T_l = \sqrt{l(2l+1)/4\pi} = 42^{+12}_{-7} \mu$K. The measured spectral index of the fluctuations is consistent with zero, the value expected for the CMB. The spectral index corresponding to Galactic free-free emission, the most likely foreground contaminant, is rejected at approximately $3\sigma$. The analysis is based on three independent data sets. The first, taken in 1993, spans the 26 - 36 GHz frequency range with three frequency bands; the second was taken with the same radiometer as the first but during an independent observing campaign in 1994; and the third, also take in 1994, spans the 36-46 GHz range in three bands. For each telescope position and radiometer channel, the drifts in the instrument offset are $\le 4~\mu$K/day over a period of one month. The dependence of the inferred anisotropy on the calibration and data editing is addressed.Comment: 16 pages, 2 figures. Saskatoon 1993/1994 combined analysi

Spinning Down a Black Hole With Scalar Fields

We study the evolution of a Kerr black hole emitting scalar radiation via the Hawking process. We show that the rate at which mass and angular momentum are lost by the black hole leads to a final evolutionary state with nonzero angular momentum, namely $a/M \approx 0.555$.Comment: 4 pages (including 3 postscript figures), Revtex, uses epsf.tex, twocolumn.sty and header.sty (included). Submitted to Physical Review Letter

Dielectric anomalies and spiral magnetic order in CoCr2O4

We have investigated the structural, magnetic, thermodynamic, and dielectric properties of polycrystalline CoCr$_2$O$_4$, an insulating spinel exhibiting both ferrimagnetic and spiral magnetic structures. Below $T_c$ = 94 K the sample develops long-range ferrimagnetic order, and we attribute a sharp phase transition at $T_N$ $\approx$ 25 K with the onset of long-range spiral magnetic order. Neutron measurements confirm that while the structure remains cubic at 80 K and at 11 K; there is complex magnetic ordering by 11 K. Density functional theory supports the view of a ferrimagnetic semiconductor with magnetic interactions consistent with non-collinear ordering. Capacitance measurements on CoCr$_2$O$_4$, show a sharp decrease in the dielectric constant at $T_N$, but also an anomaly showing thermal hysteresis falling between approximately $T$ = 50 K and $T$ = 57 K. We tentatively attribute the appearance of this higher temperature dielectric anomaly to the development of \textit{short-range} spiral magnetic order, and discuss these results in the context of utilizing dielectric spectroscopy to investigate non-collinear short-range magnetic structures.Comment: & Figure

Assessment of intra and interregional genetic variation in the Eastern Red-backed Salamander, Plethodon cinereus, via analysis of novel microsatellite markers

The red-backed salamander (Plethodon cinereus) has long-served as a model system in ecology, evolution, and behavior, and studies surveying molecular variation in this species have become increasingly common over the past decade. However, difficulties are commonly encountered when extending microsatellite markers to populations that are unstudied from a genetic perspective due to high levels of genetic differentiation across this species’ range. To ameliorate this issue, we used 454 pyrosequencing to identify hundreds of microsatellite loci. We then screened 40 of our top candidate loci in populations in Virginia, Pennsylvania, and Ohio—including an isolated island population ~ 4.5 km off the shore of Lake Erie (South Bass Island). We identified 25 loci that are polymorphic in a well-studied region of Virginia and 11 of these loci were polymorphic in populations located in the genetically unstudied regions of Ohio and Pennsylvania. Use of these loci to examine patterns of variation within populations revealed that South Bass Island has low diversity in comparison to other sites. However, neither South Bass Island nor isolated populations around Cleveland are inbred. Assessment of variation between populations revealed three well defined genetic clusters corresponding to Virginia, mainland Ohio/Pennsylvania, and South Bass Island. Comparisons of our results to those of others working in various parts of the range are consistent with the idea that differentiation is lower in regions that were once glaciated. However, these comparisons also suggest that well differentiated isolated populations in the formerly glaciated portion of the range are not uncommon. This work provides novel genetic resources that will facilitate population genetic studies in a part of the red-backed salamander’s range that has not previously been studied in this manner. Moreover, this work refines our understanding of how neutral variation is distributed in this ecologically important organism

Stratigraphy and Structure of the Fall Mountain and Skitchewaug Nappes, Southwestern New Hampshire

Guidebook for field trips in southwestern New Hampshire, southeastern Vermont, and north-central Massachusetts: New England Intercollegiate Geological Conference, 80th annual meeting, October 14, 15 and 16, 1988, Keene, New Hampshire: Trip A-

Compton Heating of the Intergalactic Medium by the Hard X-ray Background

High-resolution hydrodynamics simulations of the Ly-alpha forest in cold dark matter dominated cosmologies appear to predict line widths that are substantially narrower than those observed. Here we point out that Compton heating of the intergalactic gas by the hard X-ray background (XRB), an effect neglected in all previous investigations, may help to resolve this discrepancy. The rate of gain in thermal energy by Compton scattering will dominate over the energy input from hydrogen photoionization if the XRB energy density is 0.2x/ times higher than the energy density of the UV background at a given epoch, where x is the hydrogen neutral fraction in units of 1e-6 and is the mean X-ray photon energy in units of m_ec^2. The numerical integration of the time-dependent rate equations shows that the intergalactic medium approaches a temperature of about 1.5e4 K at z>3 in popular models for the redshift evolution of the extragalactic background radiation. The importance of Compton heating can be tested experimentally by measuring the Ly-alpha line-width distribution as a function of redshift, thus the Lyman-alpha forest may provide a useful probe of the evolution of the XRB at high redshifts.Comment: LaTeX, 10 pages, 2 figures, final version to be published in the Ap