The Effect of Sample Size on Crown Size Asymmetry

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66500/2/10.1177_00220345790580101301.pd

Topical rosiglitazone is an effective anti-scarring agent in the cornea

Corneal scarring remains a major cause of blindness world-wide, with limited treatment options, all of which have side-effects. Here, we tested the hypothesis that topical application of Rosiglitazone, a Thiazolidinedione and ligand of peroxisome proliferator activated receptor gamma (PPARγ), can effectively block scar formation in a cat model of corneal damage. Adult cats underwent bilateral epithelial debridement followed by excimer laser ablation of the central corneal stroma to a depth of ~160 µm as a means of experimentally inducing a reproducible wound. Eyes were then left untreated, or received 50 µl of either 10 µM Rosiglitazone in DMSO/Celluvisc, DMSO/Celluvisc vehicle or Celluvisc vehicle twice daily for 2 weeks. Cellular aspects of corneal wound healing were evaluated with in vivo confocal imaging and post-mortem immunohistochemistry for alpha smooth muscle actin (αSMA). Impacts of the wound and treatments on optical quality were assessed using wavefront sensing and optical coherence tomography at 2, 4, 8 and 12 weeks post-operatively. In parallel, cat corneal fibroblasts were cultured to assess the effects of Rosiglitazone on TGFβ-induced αSMA expression. Topical application of Rosiglitazone to cat eyes after injury decreased αSMA expression and haze, as well as the induction of lower-order and residual, higher-order wavefront aberrations compared to vehicle-treated eyes. Rosiglitazone also inhibited TGFβ-induced αSMA expression in cultured corneal fibroblasts. In conclusion, Rosiglitazone effectively controlled corneal fibrosis in vivo and in vitro, while restoring corneal thickness and optics. Its topical application may represent an effective, new avenue for the prevention of corneal scarring with distinct advantages for pathologically thin corneas

“Beyond BIO2010: Celebration and Opportunities” at the Intersection of Mathematics and Biology

With this special edition of CBE-LSE, which focuses on connections between and integration of the biological and mathematical sciences, it is especially fitting that we report on an important symposium, Beyond BIO2010: Celebration and Opportunities,1 which was held at the National Acad- emy of Sciences (NAS) in Washington, D.C. on May 21–22, 2010. This symposium was organized to assess what progress has been made in addressing the challenges and recommendations in the National Research Council’s (NRC) report: BIO2010: Transforming Undergraduate Education for Future Research Biologists (NRC, 2003a). Most of the presen- tations and posters at this event emphasized the increasing connections of the life and mathematical sciences in under- graduate education. The symposium was initiated by the U.S. National Committee to the International Union of Bio- logical Sciences and was hosted by the National Academies’ Board on Life Sciences.

Exploring differences in healthcare utilization of prisoners in the Canton of Vaud, Switzerland.

Prison healthcare is an important public health concern given the increasing healthcare needs of a growing and aging prison population, which accumulates vulnerability factors and suffers from higher disease prevalence than the general population. This study identifies the key factors associated with outpatient general practitioner (GP), nursing or psychiatric healthcare utilization (HCU) within prisons. Cross-sectional data systematically collected by the prison medical staff were obtained for a sample of 1664 adult prisoners of the Canton of Vaud, Switzerland, for the year 2011. They contain detailed information on demographics (predisposing factors), diagnosed chronic somatic and psychiatric disorders (needs factors), as well as prison stay characteristics (contextual factors). For GP, nurse and psychiatric care, two-part regressions are used to model separately the probability and the volume of HCU. Predisposing factors are generally not associated with the probability to use healthcare services after controlling for needs factors. However, female inmates use higher volumes of care, and the volume of GP consultations increases with age. Chronic somatic and psychiatric conditions are the most important predictors of the probability of HCU, but associations with volumes differ in their magnitude and significance across disease groups. Infectious, musculoskeletal, nervous and circulatory diseases actively mobilize GP and nursing staff. Schizophrenia, illicit drug and pharmaceuticals abuse are strongly positively associated with psychiatric and nurse HCU. The occupancy rate displays positive associations among contextual factors. Prison healthcare systems face increasingly complex organizational, budgetary and ethical challenges. This study provides relevant insights into the HCU patterns of a marginalized and understudied population

Spectroscopy of Nine Cataclysmic Variable Stars

We present optical spectroscopy of nine cataclysmic binary stars, mostly dwarf novae, obtained primarily to determine orbital periods Porb. The stars and their periods are LX And, 0.1509743(5) d; CZ Aql, 0.2005(6) d; LU Cam, 0.1499686(4) d; GZ Cnc, 0.0881(4) d; V632 Cyg, 0.06377(8) d; V1006 Cyg, 0.09903(9) d; BF Eri, 0.2708804(4) d; BI Ori, 0.1915(5) d; and FO Per, for which Porb is either 0.1467(4) or 0.1719(5) d. Several of the stars proved to be especially interesting. In BF Eri, we detect the absorption spectrum of a secondary star of spectral type K3 +- 1 subclass, which leads to a distance estimate of approximately 1 kpc. However, BF Eri has a large proper motion (100 mas/yr), and we have a preliminary parallax measurement that confirms the large proper motion and yields only an upper limit for the parallax. BF Eri's space velocity is evidently large, and it appears to belong to the halo population. In CZ Aql, the emission lines have strong wings that move with large velocity amplitude, suggesting a magnetically-channeled accretion flow. The orbital period of V1006 Cyg places it squarely within the 2- to 3-hour "gap" in the distribution of cataclysmic binary orbital periods.Comment: 31 pages, 5 postscript and one PNG figure. Accepted for PAS

Constraining the runaway dilaton and quintessential dark energy

Dark Energy is some of the weirdest and most mysterious stuff in the universe that tends to increase the rate of expansion of the universe. Two commonly known forms of dark energy are the cosmological constant, a constant energy density filling space homogeneously, and scalar fields such as quintessence or moduli whose energy density can vary with time. We explore one particular model for dynamic dark energy; quintessence driven by a scalar dilaton field. We propose an ansatz for the form of the dilaton field, $|\phi(a)|/m_P \equiv \alpha_1 \ln t+ \alpha_2 t^n=\alpha\ln a+ \beta\, a^{2\zeta}$, where $a$ is the scale factor and $\alpha$ and $\zeta$ are parameters of the model. This phenomenological ansatz for $\phi$ can be motivated by generic solutions of a scalar dilaton field in many effective string theory and string-inspired gravity models in four dimensions. Using a compilation of current data including type Ia supernovae, we impose observational constraints on the slope parameters like $\alpha$ and $\zeta$ and then discuss the relation of our results to analytical constrains on various cosmological parameters, including the dark energy equation of state. Sensible constraints are imposed on model parameters like $\alpha$ and $\zeta$ as well as on the dark energy/dark matter couplings using results from structure formation. The constraints of this model are shown to encompass the cosmological constant limit within $1\sigma$ error bars.Comment: 32 pages, several eps figures; refs added, matches published versio

Salivary melatonin onset in youth at familial risk for bipolar disorder

Melatonin secretion and polysomnography (PSG) were compared among a group of healthy adolescents who were at high familial risk for bipolar disorder (HR) and a second group at low familial risk (LR). Adolescent participants (n = 12) were a mean age 14 ± 2.3 years and included 8 females and 4 males. Saliva samples were collected under standardized condition light (red light) and following a 200 lux light exposure over two consecutive nights in a sleep laboratory. Red Light Melatonin onset (RLMO) was defined as saliva melatonin level exceeding the mean of the first 3 readings plus 2 standard deviations. Polysomnography was also completed during each night. HR youth, relative to LR, experienced a significantly earlier melatonin onset following 200 lux light exposure. Polysomnography revealed that LR youth, relative to HR, spent significantly more time in combined stages 3 and 4 (deep sleep) following red light exposure. Additionally, regardless of the group status (HR or LR), there was no significant difference in Red Light Melatonin Onset recorded at home or in the laboratory, implying its feasibility and reliability

Population structure and plumage polymorphism: The intraspecific evolutionary relationships of a polymorphic raptor, Buteo jamaicensis harlani

<p>Abstract</p> <p>Background</p> <p>Phenotypic and molecular genetic data often provide conflicting patterns of intraspecific relationships confounding phylogenetic inference, particularly among birds where a variety of environmental factors may influence plumage characters. Among diurnal raptors, the taxonomic relationship of <it>Buteo jamaicensis harlani </it>to other <it>B. jamaicensis </it>subspecies has been long debated because of the polytypic nature of the plumage characteristics used in subspecies or species designations.</p> <p>Results</p> <p>To address the evolutionary relationships within this group, we used data from 17 nuclear microsatellite loci, 430 base pairs of the mitochondrial control region, and 829 base pairs of the melanocortin 1 receptor (<it>Mc1r</it>) to investigate molecular genetic differentiation among three <it>B. jamaicensis </it>subspecies (<it>B. j. borealis</it>, <it>B. j. calurus</it>, <it>B. j. harlani</it>). Bayesian clustering analyses of nuclear microsatellite loci showed no significant differences between <it>B. j. harlani </it>and <it>B. j. borealis</it>. Differences observed between <it>B. j. harlani </it>and <it>B. j. borealis </it>in mitochondrial and microsatellite data were equivalent to those found between morphologically similar subspecies, <it>B. j. borealis </it>and <it>B. j. calurus</it>, and estimates of migration rates among all three subspecies were high. No consistent differences were observed in <it>Mc1r </it>data between <it>B. j. harlani </it>and other <it>B. jamaicensis </it>subspecies or between light and dark color morphs within <it>B. j. calurus</it>, suggesting that <it>Mc1r </it>does not play a significant role in <it>B. jamaicensis </it>melanism.</p> <p>Conclusions</p> <p>These data suggest recent interbreeding and gene flow between <it>B. j. harlani </it>and the other <it>B. jamaicensis </it>subspecies examined, providing no support for the historical designation of <it>B. j. harlani </it>as a distinct species.</p

Individual Behaviors Dominate the Dynamics of an Urban Mountain Lion Population Isolated by Roads

SummaryLarge carnivores can be particularly sensitive to the effects of habitat fragmentation on genetic diversity [1, 2]. The Santa Monica Mountains (SMMs), a large natural area within Greater Los Angeles, is completely isolated by urban development and the 101 freeway to the north. Yet the SMMs support a population of mountain lions (Puma concolor), a very rare example of a large carnivore persisting within the boundaries of a megacity. GPS locations of radio-collared lions indicate that freeways are a near-absolute barrier to movement. We genotyped 42 lions using 54 microsatellite loci and found that genetic diversity in SMM lions, prior to 2009, was lower than that for any population in North America except in southern Florida, where inbreeding depression led to reproductive failure [3–5]. We document multiple instances of father-daughter inbreeding and high levels of intraspecific strife, including the unexpected behavior of a male killing two of his offspring and a mate and his son killing two of his brothers. Overall, no individuals from the SMMs have successfully dispersed. Gene flow is critical for this population, and we show that a single male immigrated in 2009, successfully mated, and substantially enhanced genetic diversity. Our results imply that individual behaviors, most likely caused by limited area and reduced opportunities to disperse, may dominate the fate of small, isolated populations of large carnivores. Consequently, comprehensive behavioral monitoring can suggest novel solutions for the persistence of small populations, such as the transfer of individuals across dispersal barriers