Management of the phosphorus-cladophora dynamic at a site on lake Ontario using a multi-module bioavailable P model

The filamentous green alga Cladophora grows to nuisance proportions in Lake Ontario. Stimulated by high phosphorus concentrations, nuisance growth results in the degradation of beaches and clogging of industrial water intakes with attendant loss of beneficial uses. We develop a multi-module bioavailable phosphorus model to examine the efficacy of phosphorus management strategies in mitigating nuisance algal growth. The model platform includes modules simulating hydrodynamics (FVCOM), phosphorus-phytoplankton dynamics (GEM) and Cladophora growth (GLCMv3). The model is applied along a 25 km stretch of the Lake Ontario nearshore, extending east from Toronto, ON and receiving effluent from three wastewater treatment plants. Simulation results identify the Duffin Creek wastewater treatment plant effluent as a driving force for nuisance conditions of Cladophora growth, as reflected in effluent bioavailable phosphorus concentrations and the dimensions of the plant’s phosphorus footprint. Simulation results demonstrate that phosphorus removal by chemically enhanced secondary treatment is insufficient to provide relief from nuisance conditions. Tertiary treatment (chemically enhanced secondary treatment with ballasted flocculation) is shown to eliminate phosphorus-saturated conditions associated with the Duffin Creek wastewater treatment plant effluent, providing local relief from nuisance conditions. Management guidance presented here has wider application at sites along the highly urbanized Canadian nearshore of Lake Ontario

Induced Anticlinic Ordering and Nanophase Segregation of Bow-Shaped Molecules in a Smectic Solvent

Recent experiments indicate that doping low concentrations of bent-core molecules into calamitic smectic solvents can induce anticlinic and biaxial smectic phases. We have carried out Monte Carlo (MC) simulations of mixtures of rodlike molecules (hard spherocylinders with length/breadth ratio $L_{\rm rod}/D = 5$) and bow- or banana-shaped molecules (hard spherocylinder dimers with length/breadth ratio $L_{ban}/D = 5$ or 2.5 and opening angle $\psi$) to probe the molecular-scale organization and phase behavior of rod/banana mixtures. We find that a low concentration (3%) of $L_{ban}/D = 5$ dimers induces anticlinic (SmC$_A$) ordering in an untilted smectic (SmA) phase for $100^\circ \le \psi < 150^\circ$. For smaller $\psi$, half of each bow-shaped molecule is nanophase segregated between smectic layers, and the smectic layers are untilted. For $L_{ban}/D = 2.5$, no tilted phases are induced. However, with decreasing $\psi$ we observe a sharp transition from {\sl intralamellar} nanophase segregation (bow-shaped molecules segregated within smectic layers) to {\sl interlamellar} nanophase segregation (bow-shaped molecules concentrated between smectic layers) near $\psi = 130^\circ$. These results demonstrate that purely entropic effects can lead to surprisingly complex behavior in rod/banana mixtures.Comment: 5 pages Revtex, 7 postscript figure

Does antenatal micronutrient supplementation improve children’s cognitive function? Evidence from the follow-up of a double-blind randomised controlled trial in Nepal

INTRODUCTION: Multiple Micronutrient (MMN) supplementation during pregnancy can decrease the proportion of infants born low birth weight and small for gestational age. Supplementation could also enhance children’s cognitive function by improving access to key nutrients during fetal brain development and increasing birth weight, especially in areas where undernutrition is common. We tested the hypothesis that children whose mothers received MMN supplementation during pregnancy would have higher intelligence in early adolescence compared with those receiving Iron and Folic Acid (IFA) only. METHODS: We followed up children in Nepal, whose mothers took part in a double-blind Randomised Controlled Trial (RCT) that compared the effects on birth weight and gestational duration of antenatal MMN versus IFA supplementation. We assessed children’s Full Scale Intelligence Quotient (FSIQ) using the Universal Non-verbal Intelligence Test (UNIT), and their executive function using the counting Stroop test. The parent trial was registered as ISRCTN88625934. RESULTS: We identified 813 (76%) of the 1069 children whose mothers took part in the parent trial. We found no differences in FSIQ at 12 years between MMN and IFA groups (absolute difference in means (diff): 1.25, 95% CI −0.57 to 3.06). Similarly, there were no differences in mean UNIT memory (diff: 1.41, 95% CI −0.48 to 3.30), reasoning (diff: 1.17, 95% CI −0.72 to 3.06), symbolic (diff: 0.97, 95% CI −0.67 to 2.60) or non-symbolic quotients (diff: 1.39, 95% CI −0.60 to 3.38). CONCLUSION: Our follow-up of a double-blind RCT in Nepal found no evidence of benefit from antenatal MMN compared with IFA for children’s overall intelligence and executive function at 12 years

A regressive model for dynamic instabilities during the condensation of R404A and R507 refrigerants

This paper presents the results of experimental research and mathematical modelling on the influence of dynamic instabilities on the condensation phase change of R507 refrigerant in tubular mini-channels. This agent is currently being utilised as a temporary substitute for R404A, with R448A intended as the target substitute. In addition to the results, this paper contains a dimensional analysis procedure based on the Π-Buckingham theorem that has allowed for the development of a regressive model for the velocities of the dynamic instabilities. The experimental part of this paper was conducted using tubular mini-channels with internal diameters of 1.44, 2.3, and 3.3 mm.http://www.elsevier.com/locate/ijhmt2020-10-01hj2019Mechanical and Aeronautical Engineerin

What Research Ethics Should Learn from Genomics and Society Research: Lessons from the ELSI Congress of 2011

Research on the ethical, legal, and social implications (ELSI) of human genomics has devoted significant attention to the research ethics issues that arise from genomic science as it moves through the translational process. Given the prominence of these issues in today's debates over the state of research ethics overall, these studies are well positioned to contribute important data, contextual considerations, and policy arguments to the wider research ethics community's deliberations, and ultimately to develop a research ethics that can help guide biomedicine's future. In this essay, we illustrate this thesis through an analytic summary of the research presented at the 2011 ELSI Congress, an international meeting of genomics and society researchers. We identify three pivotal factors currently shaping genomic research, its clinical translation, and its societal implications: (1) the increasingly blurred boundary between research and treatment; (2) uncertainty — that is, the indefinite, indeterminate, and incomplete nature of much genomic information and the challenges that arise from making meaning and use of it; and (3) the role of negotiations between multiple scientific and non-scientific stakeholders in setting the priorities for and direction of biomedical research, as it is increasingly conducted “in the public square.

The role of parental achievement goals in predicting autonomy-supportive and controlling parenting

Although autonomy-supportive and controlling parenting are linked to numerous positive and negative child outcomes respectively, fewer studies have focused on their determinants. Drawing on achievement goal theory and self-determination theory, we propose that parental achievement goals (i.e., achievement goals that parents have for their children) can be mastery, performance-approach or performance-avoidance oriented and that types of goals predict mothers' tendency to adopt autonomy-supportive and controlling behaviors. A total of 67 mothers (aged 30-53 years) reported their goals for their adolescent (aged 13-16 years; 19.4 % girls), while their adolescent evaluated their mothers' behaviors. Hierarchical regression analyses showed that parental performance-approach goals predict more controlling parenting and prevent acknowledgement of feelings, one autonomy-supportive behavior. In addition, mothers who have mastery goals and who endorse performance-avoidance goals are less likely to use guilt-inducing criticisms. These findings were observed while controlling for the effect of maternal anxiety

Transkingdom Networks: A Systems Biology Approach to Identify Causal Members of Host-Microbiota Interactions

Improvements in sequencing technologies and reduced experimental costs have resulted in a vast number of studies generating high-throughput data. Although the number of methods to analyze these "omics" data has also increased, computational complexity and lack of documentation hinder researchers from analyzing their high-throughput data to its true potential. In this chapter we detail our data-driven, transkingdom network (TransNet) analysis protocol to integrate and interrogate multi-omics data. This systems biology approach has allowed us to successfully identify important causal relationships between different taxonomic kingdoms (e.g. mammals and microbes) using diverse types of data

Supracervical hysterectomy versus total abdominal hysterectomy: perceived effects on sexual function

BACKGROUND: Our investigation sought to compare changes in sexual function following supracervical hysterectomy (SCH) and total abdominal hysterectomy (TAH). METHODS: A retrospective chart review was performed to identify all patients who underwent supracervical hysterectomy or total abdominal hysterectomy at a tertiary care center. Patients who met criteria for participation were sent a one page confidential, anonymous questionnaire to assess sexual function experienced both pre- and postoperatively. A total of 69 patients in each group were eligible for participation. A multiple logistic regression model was used to analyze measured variables. RESULTS: Forty-eight percent (n = 33) of women undergoing a SCH returned the questionnaire, while 39% (n = 27) of those undergoing a TAH chose to participate. There were no significant demographic differences between the two groups. Patients who underwent TAH reported worse postoperative sexual outcome than SCH patients with respect to intercourse frequency, orgasm frequency and overall sexual satisfaction (P = 0.01, 0.03, and 0.03, respectively). Irrespective of type of hysterectomy, 35% of patients who underwent bilateral salpingoophorectomy (BSO) with hysterectomy experienced worse overall sexual satisfaction compared to 3% of patients who underwent hysterectomy alone (P = 0.02). CONCLUSIONS: Our data suggest that TAH patients experienced worse postoperative sexual function than SCH patients with respect to intercourse frequency and overall sexual satisfaction. Irrespective of type of hysterectomy, patients who underwent bilateral salpingoophorectomy experienced worse overall sexual satisfaction

Social interaction, noise and antibiotic-mediated switches in the intestinal microbiota

The intestinal microbiota plays important roles in digestion and resistance against entero-pathogens. As with other ecosystems, its species composition is resilient against small disturbances but strong perturbations such as antibiotics can affect the consortium dramatically. Antibiotic cessation does not necessarily restore pre-treatment conditions and disturbed microbiota are often susceptible to pathogen invasion. Here we propose a mathematical model to explain how antibiotic-mediated switches in the microbiota composition can result from simple social interactions between antibiotic-tolerant and antibiotic-sensitive bacterial groups. We build a two-species (e.g. two functional-groups) model and identify regions of domination by antibiotic-sensitive or antibiotic-tolerant bacteria, as well as a region of multistability where domination by either group is possible. Using a new framework that we derived from statistical physics, we calculate the duration of each microbiota composition state. This is shown to depend on the balance between random fluctuations in the bacterial densities and the strength of microbial interactions. The singular value decomposition of recent metagenomic data confirms our assumption of grouping microbes as antibiotic-tolerant or antibiotic-sensitive in response to a single antibiotic. Our methodology can be extended to multiple bacterial groups and thus it provides an ecological formalism to help interpret the present surge in microbiome data.Comment: 20 pages, 5 figures accepted for publication in Plos Comp Bio. Supplementary video and information availabl

Molecular markers and mechanisms of stroke: RNA studies of blood in animals and humans

Whole genome expression microarrays can be used to study gene expression in blood, which comes in part from leukocytes, immature platelets, and red blood cells. Since these cells are important in the pathogenesis of stroke, RNA provides an index of these cellular responses to stroke. Our studies in rats have shown specific gene expression changes 24 hours after ischemic stroke, hemorrhage, status epilepticus, hypoxia, hypoglycemia, global ischemia, and following brief focal ischemia that simulated transient ischemic attacks in humans. Human studies show gene expression changes following ischemic stroke. These gene profiles predict a second cohort with >90% sensitivity and specificity. Gene profiles for ischemic stroke caused by large-vessel atherosclerosis and cardioembolism have been described that predict a second cohort with >85% sensitivity and specificity. Atherosclerotic genes were associated with clotting, platelets, and monocytes, and cardioembolic genes were associated with inflammation, infection, and neutrophils. These gene profiles predicted the cause of stroke in 58% of cryptogenic patients. These studies will provide diagnostic, prognostic, and therapeutic markers, and will advance our understanding of stroke in humans. New techniques to measure all coding and noncoding RNAs along with alternatively spliced transcripts will markedly advance molecular studies of human stroke