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Data associated with An Improved Method for Interpretation of Riverine Concentration-Discharge Relationships Indicates Long-Term Shifts in Reservoir Sediment Trapping
No full textDerived from river monitoring data, concentration-discharge (C-Q) relationships are powerful indicators of export dynamics. Proper interpretation of such relationships can be made complex, however, if the ln(C)~ln(Q) relationships are nonlinear or if the relationships change over time, season, or discharge. Methods of addressing these issues by ‘binning’ data can introduce artifacts that obscure underlying interactions among time, discharge, and season. Here we illustrate these issues and propose an alternative method that uses the regression coefficients of the recently-developed WRTDS (‘Weighted Regressions on Time, Discharge, and Season’) model for examining (C-Q) relationships in long-term, discretely-sampled data for various water-quality constituents, including their uncertainties. The method is applied to sediment concentration data from Susquehanna River at Conowingo Dam, Maryland to illustrate how the coefficients can be accessed and presented in ways that provide additional insights toward the interpretation of river water-quality data, which reaffirms the recently-documented decadal-scale decline in reservoir trapping performance
Data associated with publication "Dynamic modulation of visual and electrosensory gains for locomotor control"
No full textData files and source code associated with the statistical methods and plots from the publication. From the publication abstract: Animal nervous systems resolve sensory conflict for the control of movement. For example, the glass knifefish,
Eigenmannia virescens, relies on visual and electrosensory feedback as it swims to maintain position within a moving refuge. To study how signals from these two parallel sensory streams are used in refuge tracking, we constructed a novel augmented reality apparatus that enables the independent manipulation of visual and electrosensory cues to freely swimming fish (N=5). We evaluated the linearity of multisensory integration, the change to the relative perceptual weights given to vision an
d electrosense in relation to sensory salience, and the effect of the magnitude of sensory conflict on sensorimotor gain. First, we found that tracking behaviour obeys superposition of the sensory inputs, suggesting linear sensorimotor integration. In addition, fish rely more on vision when electrosensory salience is reduced, suggesting that fish dynamically alter sensorimotor gains in a manner consistent with Bayesian integration. However, the magnitude of sensory conflict did not significantly affect sensorimotor gain. These studies lay the theoretical and experimental groundwork for future work investigating multisensory control of locomotion
Data associated with the publication: Decadal-scale export of nitrogen, phosphorus, and sediment from the Susquehanna River basin, USA: Analysis and synthesis of temporal and spatial patterns
No full textFrom the study abstract: The export of nitrogen (N), phosphorus (P), and suspended sediment (SS) is a long-standing management concern for the Chesapeake Bay watershed, USA. Here we present a comprehensive evaluation of nutrient and sediment loads over the last three decades at multiple locations in the Susquehanna River basin (SRB), Chesapeake's largest tributary watershed. Sediment and nutrient riverine loadings, including both dissolved and particulate fractions, have generally declined at
all sites upstream of Conowingo Dam (non-tidal SRB outlet). Period-of-record declines in riverine yield are generally smaller than those in source input, suggesting the possibility of legacy contributions. Consistent with other watershed studies, these results reinforce the importance of considering lag time between the implementation of management actions and achievement of river quality improvement. Whereas flow-normalized loadings for particulate species have increased recently below Conowingo Reservoir, those for upstream sites have declined, thus substantiating conclusions from prior studies about decreased reservoir trapping efficiency. In regard to streamflow effects, statistically significant log-linear relationships between annual streamflow and annual constituent load suggest the dominance of hydrological control on the inter-annual variability of constituent export. Concentration-discharge relationships revealed general chemostasis and mobilization effects for dissolved and particulate species, respectively, both suggesting transport-limitation conditions. In addition to affecting annual export rates, streamflow has also modulated the relative importance of dissolved and particulate fractions, as reflected by its negative correlations with dissolved P/total P, dissolved N/total N, particulate P/SS, and total N/total P ratios. For land-use effects, period-of-record median annual yields of N, P, and SS all correlate positively with the area fraction of non-forested land but negatively with that of forested land under all hydrological conditions. Overall, this work has informed understanding with respect to four major factors affecting constituent export (i.e., source input, reservoir modulation, streamflow, and land use) and demonstrated the value of long-term river monitoring.
Note: This data archive for Zhang et al. (2016) [10.1016/j.scitotenv.2016.03.104] covers years between 1980s and 2013, and thus includes two additional years of data beyond those used in Zhang et al. (2013) [10.1016/j.scitotenv.2013.02.012]. Additionally, the applied WRTDS algorithms were based on EGRET version 2.2.0 as opposed to WRTDS version 4c in Zhang et al. (2013). The most important differences relate to the handling of edge effects and multiple samples on a single day.</p
Data associated with the publication: Intraurban Temperature Variability in Baltimore
No full textTemperature data from a low cost sensor network deployed in summer 2015 in Baltimore
Data associated with the publication: Figure-ground organization in visual cortex for natural scenes.
No full textFigure-ground organization and border-ownership assignment are essential for understanding natural scenes. It has been shown that many neurons in the macaque visual cortex signal border-ownership in displays of simple geometric shapes such as squares, but how well these neurons resolve border-ownership in natural scenes is not known. We studied area V2 neurons in behaving macaques with static images of complex natural scenes. We found that about half of the neurons were border-ownership selective for contours in natural scenes and this selectivity originated from the image context. The border-ownership signals emerged within 70 ms after stimulus onset, only ~ 30 ms after response onset. A substantial fraction of neurons were highly consistent across scenes. Thus, the cortical mechanisms of figure-ground organization are fast and efficient even in images of complex natural scenes. Understanding how the brain performs this task so fast remains a challenge.</p
Data associated with Long-term seasonal trends of nitrogen, phosphorus, and suspended sediment load from the non-tidal Susquehanna River Basin to Chesapeake Bay
No full textFrom the study abstract: Reduction of nitrogen (N), phosphorus (P), and suspended sediment (SS) load has been a principal focus of Chesapeake Bay Watershed management for decades. To evaluate the progress of management actions in the Bay's largest tributary, the Susquehanna River, we analyzed the long-term seasonal trends of flow-normalized N, P, and SS load over the last two to three decades, both above and below the Lower Susquehanna River Reservoir System. Our results indicate that annual
and decadal-scale trends of nutrient and sediment load generally followed similar patterns in all four seasons, implying that changes in watershed function and land use had similar impacts on nutrient and sediment load at all times of the year. Above the reservoir system, the combined loads from the Marietta and Conestoga Stations indicate general trends of N, P, and SS reduction in the Susquehanna River Basin, which can most likely be attributed to a suite of management actions on point, agricultural, and stormwater sources. In contrast, upward trends of SS and particulate-associated P and N were generally observed below the Conowingo Reservoir since the mid-1990s. Our analyses suggest that (1) the reservoirs' capacity to trap these materials has been diminishing over the past two to three decades, and especially so for SS and P since the mid-1990s, and that (2) the Conowingo Reservoir has already neared its sediment storage capacity. These changes in reservoir performance will pose significant new kinds of challenges to attainment of total maximum daily load goals for the Susquehanna River Basin, and particularly if also accompanied by increases in storm frequency and intensity due to climate change. Accordingly, the reservoir issue may need to be factored into the proper establishment of regulatory load requirements and the development of watershed implementation plans.
Note: This data archive for Zhang et al. (2013) [10.1016/j.scitotenv.2013.02.012] stores data that were obtained based on the WRTDS algorithms, version 4c. This archive also stores updated and unpublished estimates in the data folder 'B. Unpublished Data, Codes, and Output' that were obtained in 2014 using longer records (~ two additional years of data) and updated codes (i.e., EGRET version 2.2.0). The most important differences relate to the handling of edge effects.</p
Data associated with the PLOS publication "Correlates of intra-household ITN use in Liberia: A multilevel analysis of household survey data"
No full textMalaria is a major cause of morbidity and mortality in Liberia. Access is a key determinant of ITN use but it is not the only one; prior studies have identified individual, household, and community level factors that affect ITN use. However, studies have generally not assessed the psychosocial or ideational determinants of ITN use. Using 2014 household survey data, this manuscript examines the socio-demographic, ideational, household, and community factors associated with household member use of ITNs in Liberia. Multilevel modeling was used to assess fixed effects at the individual, household, and community levels, and random effects at the household and cluster levels. The data showed significant residual clustering at the household level, indicating that there were unmeasured factors operating at this level that are associated with ITN use. Age, sex, number of ITNs in household, and female caregiver’s perceived severity of malaria, perceived self-efficacy to detect a complicated case of malaria, and exposure to the ‘Take Cover’ communication campaign were positively associated with ITN use by members of her household. The association with household size was negative
Data associated with Wu et al. 2016 Tuning and stabilizing topological insulator Bi2Se3 in the intrinsic regime by charge extraction with organic overlayers
No full textIn this work, we use charge extraction via organic overlayer deposition to lower the chemical potential of topological insulator (TI) Bi2Se3 thin films into the intrinsic (bulk-insulating) regime. We demonstrate the tuning and stabilization of intrinsic topological insulators at high mobility with low-cost organic films. With the protection of the organic charge extraction layers tetrafluorotetracyanoquinodimethane or tris(acetylacetonato)cobalt(III) (Co(acac)3), the sample is stable in the atmosphere with chemical potential ∼135 meV above the Dirac point (85 meV below the conduction band minimum, well within the topological insulator regime) after four months, which is an extraordinary level of environmental stability. The Co complex demonstrates the use of an organometallic for modulating TI charge density. The mobility of surface state electrons is enhanced as high as ∼2000 cm2/V s. Even at room temperature, a true topologically insulating state is realized and stabilized for months' exposure to the atmosphere
Immigrant Incorporation in East Asian Democracies (IIEAD) Project: Focus Group Interviews in Japan [collection]
No full textImmigrant Incorporation in East Asian Democracies (Cambridge University Press, 2020) is based on 31 months of fieldwork conducted in Japan, South Korea, and Taiwan from 2009 to 2016. This book examines how the civic legacies of past struggles for democracy shape current movements for immigrant rights. Examining three industrial democracies in Northeast Asia with overlapping immigration and citizenship policies, immigrant populations, and immigration histories, this book offers insights into the gaps between state policies and immigrant political behavior across similarly situated countries. In addition to comparing policy reforms, state-institutionalized rights for migrants, and immigrant incorporation policies, programs, and services, this project seeks to better understand the process of political incorporation through the lens of migrants themselves. In order to understand the incentives and disincentives for particular forms of political engagement as well as immigrant strategies for political empowerment, the methods employed must allow the respondents to generate their own questions, concepts, and categorizations. In addition to Japanese, South Korean, and Taiwanese government publications and archival materials, the project relies on a combination of questionnaires, over 150 in-depth interviews with immigrants, pro-immigrant activists, and government officials, and 28 focus groups with immigrant communities in the three countries. The Immigrant Incorporation in East Asian Democracies (IIEAD) Project contains the focus group data associated with this book. In Japan, the focus groups consisted of migrants from the Korean peninsula, mainland China, the Philippines, Brazil, Peru, Bangladesh, and Ethiopia; in Korea, participants were nationals of mainland China, Taiwan, Vietnam, the Philippines, Mongolia, and Myanmar; and, in Taiwan, participants consisted of migrants from Vietnam, Indonesia, Thailand, and the Philippines. The IIEAD collection contains transcripts and English translations of 16 focus groups from the study: eight conducted in Japan and eight in South Korea. The focus group transcripts from Taiwan are not included in the IIEAD collection due to their sensitive nature. In order to ensure the confidentiality of the focus group participants, all personal identifiers have been removed from the transcripts in the IIEAD collection, including participants’ names, self-introductions at the beginning of the focus groups, and informal conversations that either contained personal information or that were between participants and not meant to be directed at the group. This study collection includes the Japan focus group data
Cumulative patient data collected for LSOCA study
No full textThe Longitudinal Study of Ocular Complications of AIDS was a 15-year multi-center observational study which collected demographic, medical history, treatment, and vision-related data at quarterly visits from 2,392 patients with AIDS. Each SAS dataset in this collection relates to the cumulative patient-visits from a particular LSOCA form. For example, va.sas7bdat is the SAS dataset for the visual acuity data. Use the appropriate LSOCA form and SAS labels from the SAS PROC CONTENTS to decode each data item