Enhancing the Jaquez k Nearest Neighbor Test for Space-Time Interaction

The Jacquez k nearest neighbor test, originally developed to improve upon shortcomings of existing tests for space-time interaction, has been shown to be a robust and powerful method of detecting interaction. Despite its flexibility and power however, the test has three main shortcomings: (1) it discards important information regarding the spatial and temporal scale at which detected interac- tion takes place; (2) the results of the test have not been visualized; (3) recent research demonstrates the test to be susceptible to population shift bias. This study presents enhancements to the Jacquez k nearest neighbors test with the goal of addressing each of these three shortcomings and improving the utility of the test. Data on Burkitt’s lymphoma cases in Uganda between 1961-1975 are employed to illustrate the modifications and enhance the visual output of the test. Output from the enhanced test is compared to that provided by alternative tests of space-time interaction. Results show the enhancements presented in this study transform the Jacquez test into a complete, descriptive, and informative metric that can be used as a stand alone measure of global space-time interaction.space-time interaction, Jacquez k nearest neighbor, visualization, space-time cube, population shift bias

The Importance of Broadband Provision to Knowledge Intensive Firm Location

Despite the volume of literature afforded knowledge work and innovations in information and communications technologies (ICTs), few studies have examined the importance of ICTs to knowledge industries and the impact of their availability on firm location decisions. This study will evaluate the relative importance of ICTs to knowledge intensive firm location for select US metropolitan statistical areas (MSAs). Spatial econometric estimation techniques are used to construct models from ZIP code level data that describe the relative importance of broadband to knowledge intensive industries, as defined in this study. A global model is constructed for all relevant ZIP code areas across the continental U.S and the results are compared to metropolitan specific models. In addition to demonstrating variations by metropolitan area in the relative importance of broadband provision, the results suggest that broadband deployment initiatives will have varied outcomes on knowledge intensive firm growth and the subsequent change in the industrial composition of regional economies in future years.

The Importance of Broadband Provision to Knowledge Intensive Firm Location

Despite the volume of literature afforded knowledge work and innovations in information and communications technologies (ICTs), few studies have examined the importance of ICTs to firms in knowledge industries. This study will develop spatial econometric models to examine the relative importance of the level of broadband provision to knowledge intensive firms in select U.S.  metropolitan statistical areas (MSAs). Results demonstrate the need for both a spatial econometric and a metropolitan area specific evaluation of this relationship. They also suggest potential spillover effects to knowledge intensive firm location, which may explain why some regional economies are relatively more successful at stimulating firm growth in this increasingly important sector of the U.S economy.

New Business Activity and Employment Dynamics in the Inner City: The Case of Phoenix Arizona

Inner city revitalization efforts centered on fostering new business activity are controversial because they assume that the job creating capacity of new businesses is capable of impacting aggregate employment levels in inner city neighborhoods. Given this controversy, this article examines the link between new business activity and inner city employment growth in Phoenix, Arizona. Analytical results highlight job creation from new business activity but a net negative association between new business activity and employment growth stemming from the loss of jobs from large employers in inner city neighborhoods. This relationship highlights that encouraging new business activity is not necessarily a bad idea for local residents and customers, but should not be viewed as a panacea for all inner city problems. Instead, new business activity should be viewed as one component of multifaceted initiatives to revitalize inner city neighborhoods

Psychological Inflexibility Predicts Suicidality Over Time in College Students

Objective: It is essential to identify modifiable risk factors that can be targeted to reduce suicidal ideation (SI) and behavior in college students. Psychological inflexibility, a pattern of responding to internal experiences in a literal and rigid way, and attempting to control those experiences even when it interferes with valued living, could theoretically lead to SI or increase its intensity. Method: Psychological inflexibility and its component processes were tested as a predictor of SI in a longitudinal survey of college students (n = 603, age M = 20.62, 68.9% female, and 94.0% White) in a series of cross-sectional and longitudinal hierarchical regression models, controlling for relevant predictors such as distress and baseline SI. Interactions were also tested between psychological inflexibility and distress, cognitive defusion, values obstruction, and values progress in predicting SI. Results: Psychological inflexibility predicted SI cross-sectionally and longitudinally, controlling for distress and baseline SI. Psychological inflexibility interacted with distress, cognitive fusion, and values progress such that distress, cognitive fusion, and values progress had the strongest association with suicidal ideation among those who were high in psychological inflexibility. Conclusions: Psychological inflexibility may be a useful mechanism to target for suicide prevention in college students

High resolution HLA analysis reveals independent class I haplotypes and amino-acid motifs protective for multiple sclerosis.

We investigated association between HLA class I and class II alleles and haplotypes, and KIR loci and their HLA class I ligands, with multiple sclerosis (MS) in 412 European American MS patients and 419 ethnically matched controls, using next-generation sequencing. The DRB1*15:01~DQB1*06:02 haplotype was highly predisposing (odds ratio (OR) = 3.98; 95% confidence interval (CI) = 3-5.31; p-value (p) = 2.22E-16), as was DRB1*03:01~DQB1*02:01 (OR = 1.63; CI = 1.19-2.24; p = 1.41E-03). Hardy-Weinberg (HW) analysis in MS patients revealed a significant DRB1*03:01~DQB1*02:01 homozyote excess (15 observed; 8.6 expected; p = 0.016). The OR for this genotype (5.27; CI = 1.47-28.52; p = 0.0036) suggests a recessive MS risk model. Controls displayed no HW deviations. The C*03:04~B*40:01 haplotype (OR = 0.27; CI = 0.14-0.51; p = 6.76E-06) was highly protective for MS, especially in haplotypes with A*02:01 (OR = 0.15; CI = 0.04-0.45; p = 6.51E-05). By itself, A*02:01 is moderately protective, (OR = 0.69; CI = 0.54-0.87; p = 1.46E-03), and haplotypes of A*02:01 with the HLA-B Thr80 Bw4 variant (Bw4T) more so (OR = 0.53; CI = 0.35-0.78; p = 7.55E-04). Protective associations with the Bw4 KIR ligand resulted from linkage disequilibrium (LD) with DRB1*15:01, but the Bw4T variant was protective (OR = 0.64; CI = 0.49-0.82; p = 3.37-04) independent of LD with DRB1*15:01. The Bw4I variant was not associated with MS. Overall, we find specific class I HLA polymorphisms to be protective for MS, independent of the strong predisposition conferred by DRB1*15:01

A Multi-Regional Input-Output (MRIO) Analytical Framework for Assessing the Regional Economic Impacts of Rising Water Prices

Understanding the regional economic implications of rising water and wastewater services is important, because these services are household necessities. To date, however, there are few (if any) studies examining the link between water costs and indicators of economic vitality such as jobs, output, and regional income. To advance work on this particular topic, this paper proposes a novel methodology that estimates changes in household spending information from the Consumer Expenditure Survey (CES) for a particular change in water prices. This vector of final demand changes is then linked to multi-regional input-output (MRIO) models to estimate the regional economic impacts associated with changes in consumer spending patterns. To demonstrate this methodology, three water price increase scenarios are derived, and associated changes in final demand estimated

Mining Disaggregase Sequence Space to Safely Counter TDP-43, FUS, and α-Synuclein Proteotoxicity.

Hsp104 is an AAA+ protein disaggregase, which can be potentiated via diverse mutations in its autoregulatory middle domain (MD) to mitigate toxic misfolding of TDP-43, FUS, and α-synuclein implicated in fatal neurodegenerative disorders. Problematically, potentiated MD variants can exhibit off-target toxicity. Here, we mine disaggregase sequence space to safely enhance Hsp104 activity via single mutations in nucleotide-binding domain 1 (NBD1) or NBD2. Like MD variants, NBD variants counter TDP-43, FUS, and α-synuclein toxicity and exhibit elevated ATPase and disaggregase activity. Unlike MD variants, non-toxic NBD1 and NBD2 variants emerge that rescue TDP-43, FUS, and α-synuclein toxicity. Potentiating substitutions alter NBD1 residues that contact ATP, ATP-binding residues, or the MD. Mutating the NBD2 protomer interface can also safely ameliorate Hsp104. Thus, we disambiguate allosteric regulation of Hsp104 by several tunable structural contacts, which can be engineered to spawn enhanced therapeutic disaggregases with minimal off-target toxicity

The Hubble Deep Field South Flanking Fields

As part of the Hubble Deep Field South program, a set of shorter 2-orbit observations were obtained of the area adjacent to the deep fields. The WFPC2 flanking fields cover a contiguous solid angle of 48 square arcminutes. Parallel observations with the STIS and NICMOS instruments produce a patchwork of additional fields with optical and near-infrared (1.6 micron) response. Deeper parallel exposures with WFPC2 and NICMOS were obtained when STIS observed the NICMOS deep field. These deeper fields are offset from the rest, and an extended low surface brightness object is visible in the deeper WFPC2 flanking field. In this data paper, which serves as an archival record of the project, we discuss the observations and data reduction, and present SExtractor source catalogs and number counts derived from the data. Number counts are broadly consistent with previous surveys from both ground and space. Among other things, these flanking field observations are useful for defining slit masks for spectroscopic follow-up over a wider area around the deep fields, for studying large-scale structure that extends beyond the deep fields, for future supernova searches, and for number counts and morphological studies, but their ultimate utility will be defined by the astronomical community.Comment: 46 pages, 15 figures. Images and full catalogs available via the HDF-S at http://www.stsci.edu/ftp/science/hdfsouth/hdfs.html at present. The paper is accepted for the February 2003 Astronomical Journal. Full versions of the catalogs will also be available on-line from AJ after publicatio

Remittances and land change: A systematic review

Remittances—funds sent by migrants to family and friends back home—are an important source of global monetary flows, and they have implications for the maintenance and transformation of land systems. A number of published reviews have synthesized work on a variety of aspects of remittances (e.g., rural livelihoods, disasters, and economic development). To our knowledge, there are no reviews of work investigating the linkages between remittances and land change, broadly understood. This knowledge gap is important to address because researchers have recognized that remittances flows are a mechanism that helps to explain how migration can affect land change. Thus, understanding the specific roles remittances play in land system changes should help to clarify the multiple processes associated with migration and their independent and interactive effects. To address the state of knowledge about the connection between remittances and land systems, this paper conducts a systematic review. Our review of 51 journal articles finds that the linkages uncovered were commonly subtle and/or indirect. Very few studies looked at the direct connections between receipt of remittances and quantitative changes in land. Most commonly, the relationship between remittances and land change was found to occur through pathways from labor migration to household income to agricultural development and productivity. We find four non-exclusive pathways through which households spend remittances with consequent changes to land systems: (1) agricultural crops and livestock, (2) agricultural labor and technologies, (3) land purchases, and (4) non-agricultural purchases and consumables. In the papers reviewed, these expenditures are linked to various land system change outcomes, including land use change, soil degradation, pasture degradation, afforestation/deforestation/degradation, agricultural intensification/extensification/diversification, and no impact. These findings suggest four avenues for future research. One avenue is the use of the theoretical lens of telecoupling to understand how remittances may produce wider-scale changes in land systems. A second avenue is further examination of the impacts of shocks and disturbances to remittance flows on land change both in migrant sending and in remittance receiving areas. A third avenue is scholarship that examines the extent that household uses of remittances have a “ripple effect” on land uses in nearby interlinked systems. A fourth avenue for future work is the use of spatially explicit modeling that leverages land cover and land use data based on imagery and other geospatial information