A study has been undertaken to determine the time required for the effects of nitrogen-reducing best management practices (BMPs) implemented at the land surface to reach the Chesapeake Bay via ...groundwater transport to streams. To accomplish this, a nitrogen mass-balance regression (NMBR) model was developed and applied to seven watersheds on the Delmarva Peninsula. The model included the distribution of groundwater return times obtained from a regional groundwater-flow (GWF) model, the history of nitrogen application at the land surface over the last century, and parameters that account for denitrification. The model was (1) able to reproduce nitrate concentrations in streams and wells over time, including a recent decline in the rate at which concentrations have been increasing, and (2) used to forecast future nitrogen delivery from the Delmarva Peninsula to the Bay given different scenarios of nitrogen load reduction to the water table. The relatively deep porous aquifers of the Delmarva yield longer groundwater return times than those reported earlier for western parts of the Bay watershed. Accordingly, several decades will be required to see the full effects of current and future BMPs. The magnitude of this time lag is critical information for Chesapeake Bay watershed managers and stakeholders.
Background Few trials have examined long-term outcomes of advance care planning (ACP) interventions. We examined the efficacy of an ACP intervention on preparation for end-of-life decision making for ...dialysis patients and surrogates and for surrogates’ bereavement outcomes. Study Design A randomized trial compared an ACP intervention (Sharing Patient’s Illness Representations to Increase Trust SPIRIT) to usual care alone, with blinded outcome assessments. Setting & Participants 420 participants (210 dyads of prevalent dialysis patients and their surrogates) from 20 dialysis centers. Intervention Every dyad received usual care. Those randomly assigned to SPIRIT had an in-depth ACP discussion at the center and a follow-up session at home 2 weeks later. Outcomes & Measurements Primary outcomes: preparation for end-of-life decision making, assessed for 12 months, included dyad congruence on goals of care at end of life, patient decisional conflict, surrogate decision-making confidence, and a composite of congruence and surrogate decision-making confidence. Secondary outcomes: bereavement outcomes, assessed for 6 months, included anxiety, depression, and posttraumatic distress symptoms completed by surrogates after patient death. Results Primary outcomes: adjusting for time and baseline values, dyad congruence (OR, 1.89; 95% CI, 1.1-3.3), surrogate decision-making confidence (β = 0.13; 95% CI, 0.01-0.24), and the composite (OR, 1.82; 95% CI, 1.0-3.2) were better in SPIRIT than controls, but patient decisional conflict did not differ between groups (β = −0.01; 95% CI, −0.12 to 0.10). Secondary outcomes: 45 patients died during the study. Surrogates in SPIRIT had less anxiety (β = −1.13; 95% CI, −2.23 to −0.03), depression (β = −2.54; 95% CI, −4.34 to −0.74), and posttraumatic distress (β = −5.75; 95% CI, −10.9 to −0.64) than controls. Limitations Study was conducted in a single US region. Conclusions SPIRIT was associated with improvements in dyad preparation for end-of-life decision making and surrogate bereavement outcomes.
Composite variables: when and how Song, Mi-Kyung; Lin, Feng-Chang; Ward, Sandra E ...
Nursing research (New York),
2013 Jan-Feb, Letnik:
62, Številka:
1
Journal Article
Recenzirano
Use of composite variables is a common practice, but knowledge about what researchers should consider when creating composite variables is lacking.
The purpose of this paper was to present methods ...used to create composite variables with attention to advantages and disadvantages.
Methods of simple averaging, weighted averaging, and meaningful grouping to create composite variables are described briefly, and the context in which one method might be more suitable than the others is discussed. Study examples and comparisons of statistical power among these methods as well as Bonferroni correction are described.
Each approach to creating composite variables has advantages and disadvantages that researchers should weigh carefully. With normally distributed data, composite variables provide the greatest increases in power when the original variables (that make up the composite variable) have similar associations with the outside outcome variable.
Germinal centres are the engines of antibody evolution. Here, using human immunodeficiency virus (HIV) Env protein immunogen priming in rhesus monkeys followed by a long period without further ...immunization, we demonstrate germinal centre B (B
) cells that last for at least 6 months. A 186-fold increase in B
cells was present by week 10 compared with conventional immunization. Single-cell transcriptional profiling showed that both light- and dark-zone germinal centre states were sustained. Antibody somatic hypermutation of B
cells continued to accumulate throughout the 29-week priming period, with evidence of selective pressure. Env-binding B
cells were still 49-fold above baseline at 29 weeks, which suggests that they could remain active for even longer periods of time. High titres of HIV-neutralizing antibodies were generated after a single booster immunization. Fully glycosylated HIV trimer protein is a complex antigen, posing considerable immunodominance challenges for B cells
. Memory B cells generated under these long priming conditions had higher levels of antibody somatic hypermutation, and both memory B cells and antibodies were more likely to recognize non-immunodominant epitopes. Numerous B
cell lineage phylogenies spanning more than the 6-month germinal centre period were identified, demonstrating continuous germinal centre activity and selection for at least 191 days with no further antigen exposure. A long-prime, slow-delivery (12 days) immunization approach holds promise for difficult vaccine targets and suggests that patience can have great value for tuning of germinal centres to maximize antibody responses.
Murine models have become essential tools for understanding the complex interactions between gut microbes, their hosts, and disease. While many intra-facility factors are known to influence the ...structure of mouse microbiomes, the contribution of inter-facility variation to mouse microbiome composition, especially in the context of disease, remains under-investigated. We replicated microbiome experiments using identical mouse lines housed in two separate animal facilities and report drastic differences in composition of microbiomes based upon animal facility of origin. We observed facility-specific microbiome signatures in the context of a disease model the Ednrb (endothelin receptor type B) Hirschsprung disease mouse and in normal C57BL/6J mice. Importantly, these facility differences were independent of cage, sex, or sequencing-related influence. In addition, we investigated the reproducibility of microbiome dysbiosis previously associated with Ednrb
(knock-out; KO) mice. While we observed genotype-based differences in composition between wild-type (WT) and KO mice, these differences were inconsistent with the previously reported conclusions. Furthermore, the genotype-based differences were not identical across animal facilities. Despite this, through differential abundance testing, we identified several conserved candidate taxa and candidate operational taxonomic units that may play a role in disease promotion or protection. Overall, our findings raise the possibility that previously reported microbiome-disease associations from murine studies conducted in a single facility may be heavily influenced by facility-specific effects. More generally, these results provide a strong rationale for replication of mouse microbiome studies at multiple facilities, and for the meticulous collection of metadata that will allow the confounding effects of facility to be more specifically identified.
Despite evidence that racial diversification has increased support for the judiciary, political scientists know little about the heterogeneous effects of diversification across different population ...segments. Previous research illustrates that including Black judges increases judicial legitimacy among the Black population, but it decreases the legitimacy of the courts among the White population. We expand on this knowledge by examining the impact of adding Latinos to the bench. Our survey experiment compares White respondents’ perception of the courts based on differing levels of Latino representation in the ruling panel. Does descriptive representation in the racialized issue area of immigration signal fairness and legitimacy to White respondents? Or does the inclusion of Latino jurists in immigration cases trigger racial animosity and decreasing support for the courts? We find that when the court rules against the White respondent’s preference, they tend to penalize all-White judicial panels that rule against the perceived interest of Latinos. Additionally, we find that when presented with a Latino majority panel, White respondents who disagree with the ruling are more likely to punish the anti-Latino decisions as their levels of group consciousness increase. Ultimately, our findings illustrate how judicial diversity may affect the countermajoritarian capacity of the judiciary.
An assessment is made of contemporary effective sea-level rise (ESLR) for a sample of 40 deltas distributed worldwide. For any delta, ESLR is a net rate, defined by the combination of eustatic ...sea-level rise, the natural gross rate of fluvial sediment deposition and subsidence, and accelerated subsidence due to groundwater and hydrocarbon extraction. ESLR is estimated under present conditions using a digital data set of delta boundaries and a simple model of delta dynamics. The deltas in this study represent all major climate zones, levels of population density, and degrees of economic development. Collectively, the sampled deltas serve as the endpoint for river basins draining 30% of the Earth's landmass, and 42% of global terrestrial runoff. Nearly 300 million people inhabit these deltas. For the contemporary baseline, ESLR estimates range from 0.5 to 12.5 mm yr
−
1
. Decreased accretion of fluvial sediment resulting from upstream siltation of artificial impoundments and consumptive losses of runoff from irrigation are the primary determinants of ESLR in nearly 70% of the deltas. Approximately 20% of the deltas show accelerated subsidence, while only 12% show eustatic sea-level rise as the predominant effect. Extrapolating contemporary rates of ESLR through 2050 reveals that 8.7 million people and 28,000 km
2 of deltaic area in the sample set of deltas could suffer from enhanced inundation and increased coastal erosion. The population and area inundated rise significantly when considering increased flood risk due to storm surge. This study finds that direct anthropogenic effects determine ESLR in the majority of deltas studied, with a relatively less important role for eustatic sea-level rise. Serious challenges to human occupancy of deltaic regions worldwide are thus conveyed by factors which to date have been studied less comprehensively than the climate change–sea-level rise question.
Calorie labeling of standard menu items has been implemented at large restaurant chains across the U.S. since 2018. The objective of this study was to evaluate the cost effectiveness of calorie ...labeling at large U.S. fast-food chains.
This study evaluated the national implementation of calorie labeling at large fast-food chains from a modified societal perspective and projected its cost effectiveness over a 10-year period (2018-2027) using the Childhood Obesity Intervention Cost-Effectiveness Study microsimulation model. Using evidence from over 67 million fast-food restaurant transactions between 2015 and 2019, the impact of calorie labeling on calorie consumption and obesity incidence was projected. Benefits were estimated across all racial, ethnic, and income groups. Analyses were performed in 2022.
Calorie labeling is estimated to be cost saving; prevent 550,000 cases of obesity in 2027 alone (95% uncertainty interval=518,000; 586,000), including 41,500 (95% uncertainty interval=33,700; 50,800) cases of childhood obesity; and save $22.60 in healthcare costs for every $1 spent by society in implementation costs. Calorie labeling is also projected to prevent cases of obesity across all racial and ethnic groups (range between 126 and 185 cases per 100,000 people) and all income groups (range between 152 and 186 cases per 100,000 people).
Calorie labeling at large fast-food chains is estimated to be a cost-saving intervention to improve long-term population health. Calorie labeling is a low-cost intervention that is already implemented across the U.S. in large chain restaurants.
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