Unemployment in the Great Recession: single parents and men hit hard

This brief discusses the sweeping impact the Great Recession has had on Americans, particularly men, single parents, young adults, and people with less education. Using data from the 2007 and 2010 Annual Social and Economic Supplement of the Current Population Survey, the authors report that unemployment is highest among men and among unmarried adults, regardless of place or parenting status. Although this was also true before the recession, gaps between men and women, and the unmarried and married, have widened considerably during the recession. Also during the Great Recession, unemployment rose more in central cities and suburban places than in rural places, perhaps because rural unemployment was already high prior to the start of the recession

Mechanisms for Extracellular Electron Exchange by Geobacter Species

Understanding the mechanisms for microbial extracellular electron exchange are of interest because these processes play an important role in the biogeochemical cycles of both modern and ancient environments, development of bioenergy strategies, as well as for bioremediation applications. Only a handful of microorganisms are capable of extracellular electron exchange, one of the most thoroughly studied being the Geobacter species. Geobacter species are often the predominant Fe(III) reducing microorganisms in many soils and sediments, can exchange electrons directly via interspecies electron transfer, and can both donate or accept electrons with a wide variety of extracellular substrates including the electrode of a microbial fuel cell. This dissertation describes three research projects that aim to further understand these mechanisms and identify novel components involved in extracellular electron exchange by Geobacter species. The first uncovers components involved in extracellular electron transfer to insoluble Fe(III) oxides by Geobacter metallireducens. This project identified six c-type cytochromes, a NHL-repeat containing protein, and a gene potentially involved in pili glycosylation that were essential for reduction of insoluble Fe(III) oxide, but not for soluble Fe(III) citrate. The second research project serves to reveal and examine PilA-pili independent mechanisms for extracellular electron transfer to Fe(III) oxides by Geobacter sulfurreducens. During the course of this study a pilA-deficient strain of G. sulfurreducens adapted to reduce Fe(III) oxide via production of the c-type cytochrome PgcA, which was released into the culture medium, and was required for the newly adapted mechanism of Fe(III) oxide reduction. The third research project investigates the mechanism(s) utilized by G. sulfurreducens for extracellular electron exchange into the cell via the oxidation of the humic substance analog anthrahydroquinone-2,6-disulfonate (AHQDS) in cocultures with G. metallireducens. Cocultures initiated with strains of G. sulfurreducens deficient in genes for proteins previously identified to be important in extracellular electron exchange grew as well as the wild type strain, suggesting that mechanisms for exchanging electrons with extracellular electron donors are substantially different than for reduction of extracellular electron acceptors

The search for novel analgesics: re-examining spinal cord circuits with new tools

In this perspective, we propose the absence of detailed information regarding spinal cord circuits that process sensory information remains a major barrier to advancing analgesia. We highlight recent advances showing that functionally discrete populations of neurons in the spinal cord dorsal horn play distinct roles in processing sensory information. We then discuss new molecular, electrophysiological, and optogenetic techniques that can be employed to understand how dorsal horn circuits process tactile and nociceptive information. We believe this information can drive the development of entirely new classes of pharmacotherapies that target key elements in spinal circuits to selectively modify sensory function and blunt pain

Food Security Status and Barriers to Fruit and Vegetable Consumption in Two Economically Deprived Communities of Oakland, California, 2013-2014.

IntroductionFood security status may moderate how people perceive barriers to fruit and vegetable consumption. This study aimed to 1) describe the association between fruit and vegetable consumption and microbarriers and mezzobarriers to consumption, and 2) test whether these associations differ by food security status.MethodsWe surveyed adults (n = 531) living in 2 economically deprived communities in Oakland, California, in 2013 and 2014. Multivariate linear regression assessed associations between microbarriers (taste, cost, busyness) and mezzobarriers (produce selection, quality, and purchase ease) and fruit and vegetable consumption, derived from a 26-item dietary screener. Interactions were tested by food security status.ResultsRespondents consumed a mean 2.4 (standard deviation, 1.5) servings of fruits and vegetables daily; 39% of the sample was food insecure. Being too busy to prepare healthy foods was associated with reduced fruit and vegetable consumption (β(busyness) = -0.40; 95% confidence interval [CI], -0.52 to -0.28) among all respondents. Food security moderated the relationship between fruit and vegetable consumption and taste, cost, and perceived ease of purchase of healthy foods. Among the food secure, disliking healthy food taste (β(taste) = -0.38; 95% CI, -0.60 to -0.15) and cost (β(cost) = -0.29; 95% CI, -0.44 to -0.15) concerns were associated with lower consumptions of fruits and vegetables. Mezzobarriers were not significantly associated with consumption in either group.ConclusionPerceived time constraints influenced fruit and vegetable consumption. Taste and cost influenced fruit and vegetable consumption among the food secure and may need to be considered when interpreting analyses that describe dietary intake and designing diet-related interventions

Using Ego Network Data to Inform Agent-based Models of Diffusion

Agent-based modeling holds great potential as an analytical tool. Agent-based models (ABMs) are, however, also vulnerable to critique, as they often employ stylized social worlds, with little connection to the actual environment in question. Given these concerns, there has been a recent call to more fully incorporate empirical data into ABMs. This article falls in this tradition, exploring the benefits of using sampled ego network data in ABMs of cultural diffusion. Thus, instead of relying on full network data, which can be difficult and costly to collect, or no empirical network data, which is convenient but not empirically grounded, we offer a middle-ground, one combining ABMs with recent work on network sampling. The main question is whether this approach is effective. We provide a test of the approach using six complete networks; the test also includes a range of diffusion models (where actors follow different rules of adoption). For each network, we take a random ego network sample and use that sample to infer the full network structure. We then run a diffusion model through the known, complete networks, as well as the inferred networks, and compare the results. The results, on the whole, are quite strong: Across all analyses, the diffusion curves based on the sampled data are very similar to the curves based on the true, complete network. This suggests that ego network sampling can, in fact, offer a practical means of incorporating empirical data into an agent-based model

Activating extrinsic and intrinsic toughening mechanisms in polycrystalline ceramics and their composites via microstructural engineering

Ferroelastic toughening is one of a limited number of intrinsic toughening mechanisms available for ceramics, yet rarely is it effectively implemented due to a limited understanding of the activation mechanisms within a polycrystalline framework. In the earliest descriptions of ferroelastic toughening, terms such as the transformation strain, coercive stress and process zone parameters were included following other (extrinsic) crack tip shielding models. In the years that have followed, constitutive models have become more sophisticated, incorporating crystal orientation, rate behaviors, and several other factors. However, further development of these models has been limited by the paucity of experimental observations linking ferroelastic switching with critical, yet common, microstructural variations (i.e. grain size, nearest neighbor orientations, secondary/grain boundary phases, etc.). Here we present a multi-scale experimental approach to explore the role of stress concentration, stress transfer and localized constraint in ferroelastic domain nucleation, motion and subsequent toughening. In situ TEM nanopillar and ex situ micropillar compression on single crystal specimens extracted from a polycrystalline ceramic have been used to correlate crystallographic orientation with coercive stresses for domain nucleation and motion. The comparison between these two length scales also highlights the importance of boundary conditions on the nucleation of ferroelastic domains and sheds light on the grain size dependence of domain nucleation probability extracted from Vicker’s indentation of polycrystalline ceramics of the same composition. This insight will ultimately be coupled with grain orientation, elastic anisotropy data and quantified stress distributions during deformation to establish the early foundations of a microstructural design framework for ferroelastically toughened ceramics. Please click Additional Files below to see the full abstract

Capacity building efforts and perceptions for wildlife surveillance to detect zoonotic pathogens: comparing stakeholder perspectives.

BackgroundThe capacity to conduct zoonotic pathogen surveillance in wildlife is critical for the recognition and identification of emerging health threats. The PREDICT project, a component of United States Agency for International Development's Emerging Pandemic Threats program, has introduced capacity building efforts to increase zoonotic pathogen surveillance in wildlife in global 'hot spot' regions where zoonotic disease emergence is likely to occur. Understanding priorities, challenges, and opportunities from the perspectives of the stakeholders is a key component of any successful capacity building program.MethodsA survey was administered to wildlife officials and to PREDICT-implementing in-country project scientists in 16 participating countries in order to identify similarities and differences in perspectives between the groups regarding capacity needs for zoonotic pathogen surveillance in wildlife.ResultsBoth stakeholder groups identified some human-animal interfaces (i.e. areas of high contact between wildlife and humans with the potential risk for disease transmission), such as hunting and markets, as important for ongoing targeting of wildlife surveillance. Similarly, findings regarding challenges across stakeholder groups showed some agreement in that a lack of sustainable funding across regions was the greatest challenge for conducting wildlife surveillance for zoonotic pathogens (wildlife officials: 96% and project scientists: 81%). However, the opportunity for improving zoonotic pathogen surveillance capacity identified most frequently by wildlife officials as important was increasing communication or coordination among agencies, sectors, or regions (100% of wildlife officials), whereas the most frequent opportunities identified as important by project scientists were increasing human capacity, increasing laboratory capacity, and the growing interest or awareness regarding wildlife disease or surveillance programs (all identified by 69% of project scientists).ConclusionsA One Health approach to capacity building applied at local and global scales will have the greatest impact on improving zoonotic pathogen surveillance in wildlife. This approach will involve increasing communication and cooperation across ministries and sectors so that experts and stakeholders work together to identify and mitigate surveillance gaps. Over time, this transdisciplinary approach to capacity building will help overcome existing challenges and promote efficient targeting of high risk interfaces for zoonotic pathogen transmission

Discovery of a Metal-Line Absorber Associated with a Local Dwarf Starburst Galaxy

We present optical and near-infrared images, H I 21 cm emission maps, optical spectroscopy, and Hubble Space Telescope/Space Telescope Imaging Spectrograph ultraviolet spectroscopy of the QSO/galaxy pair SBS 1122+594/IC 691. The QSO sight line lies at a position angle of 27 degrees from the minor axis of the nearby dwarf starburst galaxy IC 691 (cz_gal = 1204+-3 km/s, L_B ~ 0.09 L*, current star formation rate = 0.08-0.24 solar masses per year) and 33 kpc (6.6 arcmin) from its nucleus. We find that IC 691 has an H I mass of M_HI = (3.6+-0.1) x 10^8 solar masses and a dynamical mass of M_dyn = (3.1+-0.5) x 10^10 solar masses. The UV spectrum of SBS 1122+594 shows a metal-line (Ly-alpha + C IV) absorber near the redshift of IC 691 at cz_abs = 1110+-30 km/s. Since IC 691 is a dwarf starburst and the SBS 1122+594 sight line lies in the expected location for an outflowing wind, we propose that the best model for producing this metal-line absorber is a starburst wind from IC 691. We place consistent metallicity limits on IC 691 ([Z/Zsun] ~ -0.7) and the metal-line absorber ([Z/Zsun] < -0.3). We also find that the galaxy's escape velocity at the absorber location is v_esc = 80+-10 km/s and derive a wind velocity of v_w = 160+-50 km/s. Thus, the evidence suggests that IC 691 produces an unbound starburst wind that escapes from its gravitational potential to transport metals and energy to the surrounding intergalactic medium.Comment: 31 pages, 8 figures; AJ in press; a version with high resolution figures can be downloaded from http://casa.colorado.edu/~keeney/research/papers/IC691.pd