Long-term Evolution of Sunspot Magnetic Fields

Independent of the normal solar cycle, a decrease in the sunspot magnetic field strength has been observed using the Zeeman-split 1564.8nm Fe I spectral line at the NSO Kitt Peak McMath-Pierce telescope. Corresponding changes in sunspot brightness and the strength of molecular absorption lines were also seen. This trend was seen to continue in observations of the first sunspots of the new solar Cycle 24, and extrapolating a linear fit to this trend would lead to only half the number of spots in Cycle 24 compared to Cycle 23, and imply virtually no sunspots in Cycle 25. We examined synoptic observations from the NSO Kitt Peak Vacuum Telescope and initially (with 4000 spots) found a change in sunspot brightness which roughly agreed with the infrared observations. A more detailed examination (with 13,000 spots) of both spot brightness and line-of-sight magnetic flux reveals that the relationship of the sunspot magnetic fields with spot brightness and size remain constant during the solar cycle. There are only small temporal variations in the spot brightness, size, and line-of-sight flux seen in this larger sample. Because of the apparent disagreement between the two data sets, we discuss how the infrared spectral line provides a uniquely direct measurement of the magnetic fields in sunspots

Optimal loading of hydrogel-based drug-delivery systems

Drug-loaded hydrogels provide a means to deliver pharmaceutical agents to specific sites within the body at a controlled rate. The aim of this paper is to understand how controlled drug release can be achieved by tuning the initial distribution of drug molecules in a hydrogel. A mathematical model is presented for a spherical drug-loaded hydrogel. The model captures the nonlinear elasticity of the polymer network and thermodynamics of swelling. By assuming that the drug molecules are dilute, the equations for hydrogel swelling and drug transport partially decouple. A fast optimisation method is developed to accurately compute the optimal initial drug concentration by minimising the error between the numerical drug-release profile and a target profile. By taking the target drug efflux to be piecewise constant, the optimal initial configuration consists of a central drug-loaded core with isolated drug packets near the free boundary of the hydrogel. The optimal initial drug concentration is highly effective at mitigating the burst effect, where a large amount of drug is rapidly released into the environment. The hydrogel stiffness can be used to further tune the rate of drug release. Although stiffer gels lead to less swelling and hence reduce the drug diffusivity, the drug-release kinetics are faster than for soft gels due to the decreased distance that drug molecules must travel to reach the free surface

Federal Participation in Innovative Public Health Financing: the Social Impact Bond Act (HR 4885) and the Pay for Performance Act (S.2691)

Social impact bonds (SIBs) are relatively new financing mechanisms that can be used to finance public health initiatives addressing issues such as asthma and infant mortality. Since 2010, when the world’s first SIB launched in the United Kingdom, several states and local governments in the United States have either launched SIBs or taken steps toward launching one. Legislation has recently been introduced in both chambers of Congress that would allow for a greater role in these arrangements. A bill introduced on June 18, 2014, to the US House of Representatives with bipartisan support would assist the efforts of state, tribal, local, and territorial (STLT) governments exploring SIBs. That bill, House Bill 4885, would authorize the federal government to enter in SIB arrangements with STLT governments. A similar bill, also with bipartisan support, was introduced in the Senate on July 30, 2014. The Senate bill, S.2691, mirrors the House bill to a large extent but contains some notable differences.Office for State, Tribal, Local and Territorial Support, Centers for Disease Control and Preventio

D.C. Circuit: Study of Gender, Race, and Ethnic Bias

The District of Columbia Circuit became the first federal circuit to establish a Task Force on race and gender bias. In 1992, the Task Force, which was comprised of judges from the D.C. Circuit, created two committees-the Special Committee on Gender and the Special Committee on Race and Ethnicity-to assist the Task Force in its research. The committees were comprised of academics, social science advisors of national recognition, and leading attorneys

Dissecting the genetic basis of comorbid epilepsy phenotypes in neurodevelopmental disorders.

BACKGROUND:Neurodevelopmental disorders (NDDs) such as autism spectrum disorder, intellectual disability, developmental disability, and epilepsy are characterized by abnormal brain development that may affect cognition, learning, behavior, and motor skills. High co-occurrence (comorbidity) of NDDs indicates a shared, underlying biological mechanism. The genetic heterogeneity and overlap observed in NDDs make it difficult to identify the genetic causes of specific clinical symptoms, such as seizures. METHODS:We present a computational method, MAGI-S, to discover modules or groups of highly connected genes that together potentially perform a similar biological function. MAGI-S integrates protein-protein interaction and co-expression networks to form modules centered around the selection of a single "seed" gene, yielding modules consisting of genes that are highly co-expressed with the seed gene. We aim to dissect the epilepsy phenotype from a general NDD phenotype by providing MAGI-S with high confidence NDD seed genes with varying degrees of association with epilepsy, and we assess the enrichment of de novo mutation, NDD-associated genes, and relevant biological function of constructed modules. RESULTS:The newly identified modules account for the increased rate of de novo non-synonymous mutations in autism, intellectual disability, developmental disability, and epilepsy, and enrichment of copy number variations (CNVs) in developmental disability. We also observed that modules seeded with genes strongly associated with epilepsy tend to have a higher association with epilepsy phenotypes than modules seeded at other neurodevelopmental disorder genes. Modules seeded with genes strongly associated with epilepsy (e.g., SCN1A, GABRA1, and KCNB1) are significantly associated with synaptic transmission, long-term potentiation, and calcium signaling pathways. On the other hand, modules found with seed genes that are not associated or weakly associated with epilepsy are mostly involved with RNA regulation and chromatin remodeling. CONCLUSIONS:In summary, our method identifies modules enriched with de novo non-synonymous mutations and can capture specific networks that underlie the epilepsy phenotype and display distinct enrichment in relevant biological processes. MAGI-S is available at https://github.com/jchow32/magi-s

Leaping through tree space: continuous phylogenetic inference for rooted and unrooted trees

Phylogenetics is now fundamental in life sciences, providing insights into the earliest branches of life and the origins and spread of epidemics. However, finding suitable phylogenies from the vast space of possible trees remains challenging. To address this problem, for the first time, we perform both tree exploration and inference in a continuous space where the computation of gradients is possible. This continuous relaxation allows for major leaps across tree space in both rooted and unrooted trees, and is less susceptible to convergence to local minima. Our approach outperforms the current best methods for inference on unrooted trees and, in simulation, accurately infers the tree and root in ultrametric cases. The approach is effective in cases of empirical data with negligible amounts of data, which we demonstrate on the phylogeny of jawed vertebrates. Indeed, only a few genes with an ultrametric signal were generally sufficient for resolving the major lineages of vertebrate. With cubic-time complexity and efficient optimisation via automatic differentiation, our method presents an effective way forwards for exploring the most difficult, data-deficient phylogenetic questions.Comment: 13 pages, 4 figures, 14 supplementary pages, 2 supplementary figure

Pelvic Organ Distribution of Mesenchymal Stem Cells Injected Intravenously after Simulated Childbirth Injury in Female Rats

The local route of stem cell administration utilized presently in clinical trials for stress incontinence may not take full advantage of the capabilities of these cells. The goal of this study was to evaluate if intravenously injected mesenchymal stem cells (MSCs) home to pelvic organs after simulated childbirth injury in a rat model. Female rats underwent either vaginal distension (VD) or sham VD. All rats received 2 million GFP-labeled MSCs intravenously 1 hour after injury. Four or 10 days later pelvic organs and muscles were imaged for visualization of GFP-positive cells. Significantly more MSCs home to the urethra, vagina, rectum, and levator ani muscle 4 days after VD than after sham VD. MSCs were present 10 days after injection but GFP intensity had decreased. This study provides basic science evidence that intravenous administration of MSCs could provide an effective route for cell-based therapy to facilitate repair after injury and treat stress incontinence