Adaptive and demographic responses of plankton populations to environmental change

Because of their large population sizes, short generation times, and clonal mode of propagation, microorganisms should often be the first members of a community to respond evolutionarily to temporal changes in the environment. Because the planktonic microbial community directly or indirectly influences all other members of aquatic ecosystems, it is useful to have a general theory for the magnitude and limits of such response. Models are presented for the expected dynamics of evolutionary change for the mean and variance of a quantitative character under natural selection toward a fixed or a moving optimum. It is also shown how the rate of population growth is related to the phenotypic composition of the population and the selective aspects of the environment. These models, which lead to the identification of extinction thresholds for the rate of environmental change beyond which a population cannot maintain itself, provide a heuristic basis for understand-ing the response of ecosystems to environmental perturbations. The analyses also indicate that clones of microorganisms isolated into novel laboratory environments are likely to undergo sub-stantial evolutionary change over periods of a few hundred days, which raises questions about the utility of such cultures for inferring ecological properties of natural populations

Adaptive evolution of molecular phenotypes

Molecular phenotypes link genomic information with organismic functions, fitness, and evolution. Quantitative traits are complex phenotypes that depend on multiple genomic loci. In this paper, we study the adaptive evolution of a quantitative trait under time-dependent selection, which arises from environmental changes or through fitness interactions with other co-evolving phenotypes. We analyze a model of trait evolution under mutations and genetic drift in a single-peak fitness seascape. The fitness peak performs a constrained random walk in the trait amplitude, which determines the time-dependent trait optimum in a given population. We derive analytical expressions for the distribution of the time-dependent trait divergence between populations and of the trait diversity within populations. Based on this solution, we develop a method to infer adaptive evolution of quantitative traits. Specifically, we show that the ratio of the average trait divergence and the diversity is a universal function of evolutionary time, which predicts the stabilizing strength and the driving rate of the fitness seascape. From an information-theoretic point of view, this function measures the macro-evolutionary entropy in a population ensemble, which determines the predictability of the evolutionary process. Our solution also quantifies two key characteristics of adapting populations: the cumulative fitness flux, which measures the total amount of adaptation, and the adaptive load, which is the fitness cost due to a population's lag behind the fitness peak.Comment: Figures are not optimally displayed in Firefo

Does a Carbonatite Deposit Influence Its Surrounding Ecosystem?

Carbonatites are unusual alkaline rocks with diverse compositions. Although previous work has characterized the effects these rocks have on soils and plants, little is known about their impacts on local ecosystems. Using a deposit within the Great Lakes–St. Lawrence forest in northern Ontario, Canada, we investigated the effect of a carbonatite on soil chemistry and on the structure of plant and soil microbial communities. This was done using a vegetation survey conducted above and around the deposit, with corresponding soil samples collected for determining soil nutrient composition and for assessing microbial community structure using 16S/ITS Illumina Mi-Seq sequencing. In some soils above the deposit a soil chemical signature of the carbonatite was found, with the most important effect being an increase in soil pH compared with the non-deposit soils. Both plants and microorganisms responded to the altered soil chemistry: the plant communities present in carbonatite-impacted soils were dominated by ruderal species, and although differences in microbial communities across the surveyed areas were not obvious, the abundances of specific bacteria and fungi were reduced in response to the carbonatite. Overall, the deposit seems to have created microenvironments of relatively basic soil in an otherwise acidic forest soil. This study demonstrates for the first time how carbonatites can alter ecosystems in situ

Mucinous Adenocarcinoma of the Scalp: Primary Cutaneous Neoplasm Versus Underlying Metastatic Disease

Primary cutaneous mucinous carcinoma (PCMC) is a rare mucin-pro- ducing malignancy derived from epithelial glandular structures. The literature re- garding this topic is mostly in the form of case reports and case series. PCMC tends to present in the elderly with predilection for the head and neck and on initial assessment it can be easily mistaken for a simple inclusion cyst. Although PCMC is often indolent in nature, in rare instances it can metastasize and should remain a differential diagnosis in a selected population. The significance in identifying PCMC is reliably differentiating it from metastatic mucinous adenocarcinoma. We present a review of literature and case of PCMC on the scalp of a 67-year-old female. (Plast Reconstr Surg Glob Open 2018;6:e1761; doi: 10.1097/GOX.0000000000001761; Published online 16 April 2018.

The chemoreceptor genes of the waterflea Daphnia pulex: many Grs but no Ors

<p>Abstract</p> <p>Background</p> <p>Chemoreception is vitally important for all animals, yet little is known about the genetics of chemoreception in aquatic organisms. The keystone species <it>Daphnia pulex</it>, a well known crustacean, is the first aquatic invertebrate to have its genome sequenced. This has allowed us the initial investigation of chemoreceptor genes in an aquatic invertebrate, and to begin the study of chemoreceptor evolution across the arthropod phylum.</p> <p>Results</p> <p>We describe 58 Grs (gustatory receptors), belonging to the insect chemoreceptor superfamily, which were identified bioinformatically in the draft genome of the crustacean waterflea <it>Daphnia pulex</it>. No genes encoding proteins similar to the insect odorant receptors (Ors) were identified. These 58 Grs form 3 distinctive subfamilies of 37, 12, and 5 genes, as well as a highly divergent singleton (Gr58). In addition, Grs55–57 share distinctive amino acid motifs and cluster with the sugar receptors of insects, and may illuminate the origin of this distinctive subfamily. ESTs, tiling array, and PCR amplification results support 34 predicted gene models, and preliminary expression data comparing the sexes indicates potential female-biased expression for some genes.</p> <p>Conclusion</p> <p>This repertoire of 58 chemoreceptors presumably mediates the many chemoperception abilities of waterfleas. While it is always possible that the entire Or gene lineage was lost at some point in the history of <it>Daphnia pulex</it>, we think it more likely that the insect Or lineage is indeed a relatively recently expanded gene lineage concomitant with the evolution of terrestriality in the insects or their hexapod ancestors.</p

The Cost of Majority-Party Bias: Amending Activity under Structured Rules

All major legislation in the House necessitates a special rule from the Rules Committee before it can be brought to the chamber floor. These rules often strictly limit floor amendments to bills considered by the House. Scholars of political parties have argued that the House majority party can bias policy output away from the floor median through its usage of restrictive rules. In this article, we argue that in order to secure the passage of restrictive rules, the majority often makes concessions to centrist legislators through the amending process. We examine this theory using a newly collected data set that includes all amendments considered by the Rules Committee during the construction of structured rules in the 109th, 110th, and 111th Congresses (2005–2010). Our results are mixed, but they do suggest that moderate members of the majority party often receive concessions via amendments for their support of the majority party's agenda-setting regime

Silicate Emission in the TW Hydrae Association

The TW Hydrae Association is the nearest young stellar association. Among its members are HD 98800, HR 4796A, and TW Hydrae itself, the nearest known classical T Tauri star. We have observed these three stars spectroscopically between 3 and 13 microns. In TW Hya the spectrum shows a silicate emission feature that is similar to many other young stars with protostellar disks. The 11.2 micron feature indicative of significant amounts of crystalline olivine is not as strong as in some young stars and solar system comets. In HR 4796A, the thermal emission in the silicate feature is very weak, suggesting little in the way of (small silicate) grains near the star. The silicate band of HD 98800 (observed by us but also reported by Sylvester and Skinner (1996)) is intermediate in strength between TW Hya and HR 4796.Comment: 22 pages, 11 figures, LaTeX2e and AAS LaTeX macros v5.0. Accepted for publication in A

The Effect of Kinesio Tape® on Lower Extremity Functional Movement Screen™ Scores

International Journal of Exercise Science 5(3) : 196-204, 2012. The purpose was to determine if application of Kinesio Tape (KT®) improves lower extremity scores on the Functional Movement Screen (FMS™). Individual FMS™ score assessments of 32 college students were obtained. The subjects were then randomized into treatment and control groups. The treatment group had a second FMS™ score after application of KT® to the lower extremity while the control group had a second FMS™ score with no intervention. 16 varsity women’s basketball players and 16 non-varsity female students (Tegner Scale: 6.84 ±1.25, Age: 19±1.2, Height: 165.1±15.1cm, Weight: 68.1±10.9kg) at a NCAA Division II institution participated. FMS™ scores were collected and recorded by the principal investigator. Data was analyzed through two way analysis of variance (ANOVA). Post hoc analysis indicated the treatment group significantly improved in comparison to the control group (Left: P\u3c.001, 95% CI: .283 - .467; Right P\u3c.001, 95% CI: .327 - .523) for both sides of the Hurdle Step. There were no interactions with Deep Squat (P=0.667) or either side of In-Line Lunge (Left: P=0.291, and Right: P=0.530). There were no interactions with either group in Deep Squat and In-Line Lunge of FMS™. However, there was a significant interaction with both groups in the Hurdle Step of FMS™. Findings from this research suggest that KT® may improve movement that incorporates a non-weight-bearing segment

State and Local Coverage Changes under Full Implementation of the Affordable Care Act

The Affordable Care Act (ACA) of 2010 includes a number of new policies intended to substantially reduce the number of people without health insurance. Key provisions to be implemented in 2014 include new health insurance exchanges, subsidies for coverage in those exchanges, health insurance market reforms, and an individual mandate. The ACA also includes an expansion of Medicaid coverage to individuals with incomes up to 138 percent of the Federal Poverty Level ($15,856 for an individual or$26,951 for family of three in 2013). The Medicaid expansion under the ACA became a state option following the Supreme Court ruling in June of 2012. At this point, it is not clear how many states will elect to expand Medicaid coverage. If all states were to do so, enrollment in Medicaid is projected to increase nationwide by about 18.1 million and the uninsured would decline by 23.1 million. This brief provides highlights from new state and sub-state estimates of how the number and composition of individuals enrolled in Medicaid/CHIP would change with full implementation of the ACA, including the Medicaid expansion (see kff.org/zooming-in-ACA). These estimates provide more detail on the projected coverage changes under the ACA at the state level than in prior research. They also provide new information on the expected coverage changes resulting from the ACA at the local level in all states. This analysis demonstrates that there is substantial variation across and within states in the magnitude and composition of the population that is projected to gain Medicaid coverage under the ACA. These estimates also provide guidance on the areas that are likely to experience the largest declines in the uninsured and where the residual uninsured are likely to be concentrated