The Effects of Phosphorus Enrichment on the Dominant Phytoplankton Communities of Chaney Lake

Chaney Lake is a temporary karst wetland located in southern Warren County, Kentucky. Because of an impermeable chert layer between the surface and the porous limestone, Chaney Lake fills with water over the winter and spring and then gradually drains over the summer. Three experiments were conducted over the course of the 1998 flooding season to assess the effects of phosphorus addition on the phytoplankton community in Chaney Lake. Ten plastic-sided mesocosms were constructed and placed in the marsh area of the wetland at three different periods: early spring, early summer, and late summer. Phosphorus in the form of K2HPO4 was added by volume to five of the enclosures, with five remaining as controls. The water chemistry parameters measured included soluble reactive phosphate, nitrates, ammonia, and ammonium. Physical parameters such as depth, temperature, dissolved oxygen, dissolved oxygen %, specific conductivity, pH, and turbidity were measured. Chlorophyll a and phytoplankton community structure were also assessed for all three of the experiments. The various parameters were analyzed with Discriminate Function Analysis, ANOVAs, and Pearson Correlations to determine whether there were significant differences between the treated and control enclosures. The results indicate significant differences (P\u3c0.05) between the treated and control enclosures with respect to nitrates, turbidity, and ammonia. There were no significant differences in SRP, chlorophyll a, DO, DO%, SPC, pH, temperature, depth, and phytoplankton composition. It was concluded that phytoplankton in Chaney Lake may not be limited by phosphorus. However, phosphorus may limit bacterioplankton, periphyton, or both. The high nutrient concentrations with low elemental ratios indicate that bacterioplankton may be more efficient in phosphorus utilization and possibly play an important role in nutrient availability for phytoplankton in the marsh area of Chaney Lake

Moderating Variables on the Relationship between Parent-Child Bonds and Mature Decentering

Developmental psychology aims to elucidate how children's early relationships influence their interactions with the world. Piaget's cognitive development theory is often noted when discussing development, and although his cognitive descriptions of decentering (i.e., perspective taking) were compelling, they neglected interpersonal contexts. Accordingly, Feffer conceptualized decentering within a social context. To expand on Feffer's consideration of the social context, the current study explored early parent-child bonds and their impact on child development, specifically interpersonal decentering, in adolescence. In the present secondary analysis of data from the Institute of Human Development longitudinal Guidance Study at the University of California, Berkeley, I hypothesized that, for both boys and girls, conflict with relatives and a parent's nervous instability would moderate the association between early strong parental bonds and more mature decentering at ages 12.5 and 18 years, and that more imaginative play, introspection, and better physical health would moderate the relationship between strong father-son bonds at age 21 months and the son's more mature decentering at age 12.5 and 18 years. The findings revealed that the association between strong father-son bonds at 21 months and the son's more mature decentering at age 12.5 was strongest when the son was less introspective compared to when the son was more introspective. When sons were in better health at ages 5-10 years and 11-17 years, their father-son bonds at age 21 months were more strongly related to more mature decentering at age 18 compared to sons who were in fair to poor health. The current study expands on the impact parental bonds, particularly paternal for sons, have on a child's social cognitive development

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements

Global, regional, and national age-sex-specific mortality for 282 causes of death in 195 countries and territories, 1980-2017: a systematic analysis for the Global Burden of Disease Study 2017.

BACKGROUND: Global development goals increasingly rely on country-specific estimates for benchmarking a nation's progress. To meet this need, the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2016 estimated global, regional, national, and, for selected locations, subnational cause-specific mortality beginning in the year 1980. Here we report an update to that study, making use of newly available data and improved methods. GBD 2017 provides a comprehensive assessment of cause-specific mortality for 282 causes in 195 countries and territories from 1980 to 2017. METHODS: The causes of death database is composed of vital registration (VR), verbal autopsy (VA), registry, survey, police, and surveillance data. GBD 2017 added ten VA studies, 127 country-years of VR data, 502 cancer-registry country-years, and an additional surveillance country-year. Expansions of the GBD cause of death hierarchy resulted in 18 additional causes estimated for GBD 2017. Newly available data led to subnational estimates for five additional countries-Ethiopia, Iran, New Zealand, Norway, and Russia. Deaths assigned International Classification of Diseases (ICD) codes for non-specific, implausible, or intermediate causes of death were reassigned to underlying causes by redistribution algorithms that were incorporated into uncertainty estimation. We used statistical modelling tools developed for GBD, including the Cause of Death Ensemble model (CODEm), to generate cause fractions and cause-specific death rates for each location, year, age, and sex. Instead of using UN estimates as in previous versions, GBD 2017 independently estimated population size and fertility rate for all locations. Years of life lost (YLLs) were then calculated as the sum of each death multiplied by the standard life expectancy at each age. All rates reported here are age-standardised