Sex, but not skin tone affects penetration of red-light (660 nm) through sites susceptible to sports injury in lean live and cadaveric tissues

Red‐light treatment is emerging as a novel therapy for promoting tissue recovery but data on red‐light penetration through human tissues are lacking. We aimed to: (1) determine the effect of light irradiance, tissue thickness, skin tone, sex and bone/muscle content on 660 nm light penetration through common sites of sports injuries, and (2) establish if cadaver tissues serve as a useful model for predicting red‐light penetration in live tissues. Live and cadaver human tissues were exposed to 660 nm light at locations across the skull, spinal cord and upper and lower limbs. Red‐light was produced by a light emitting diode array of various irradiances (15‐500 mW/cm2) and measured by a light‐probe positioned on the tissue surface opposite to the light emitting diodes. 100 mW/cm2 successfully penetrated tissue 50 mm. These results assist clinicians and researchers in determining red‐light treatment intensities for penetrating human tissues.Bootes Medical Research Foundatio

Assessment of “silent” restenosis and long-term follow-up after successful angioplasty in single vessel coronary artery disease: The value of quantitative exercise electrocardiography and quantitative coronary angiography

AbstractExercise electrocardiographic (ECG) testing during follow-up after coronary angioplasty is widely applied to evaluate the efficacy of angioplasty, even in asymptomatic patients. One hundred forty-one asymptomatic patients without previous myocardial infarction underwent quantitative exercise ECG testing and quantitative coronary angiography 1 to 6 months after successful angioplasty in single vessel coronary artery disease to 1) determine the value of exercise ECG testing to detect “silent” restenosis, and 2) assess the long-term prognostic value of exercise ECG testing and coronary angiography.The prevalence of restenosis (defined as ≥50% luminal narrowing at the dilation site) was 12% in this selected study group. Of 26 patients with an abnormal exercise ECG (ST segment depression ≥0.1 mV), only 4 (15%) showed recurrence of stenosis. Sensitivity and specificity for detection of restenosis were 24% and 82%, respectively.One hundred thirty-four patients (95%) were followed up 1 to 64 months (mean 35) after exercise ECG testing and coronary angiography. Thirty-two patients (24%) experienced a cardiac event: in 25 patients (78%) the initial event was recurrent angina pectoris (New York Heart Association class III or IV) and in 7 patients (22%) it was myocardial infarction, although cardiac death did not occur. The mean interval between exercise ECG testing and the initial cardiac events was 14 months (range 1 to 55), whereas 47% of the initial events took place ≤6 months after exercise ECG testing. An abnormal exercise test result and angiographic restenosis had, respectively, a predictive value of 36% and 41% and a relative risk of 1.7 and 1.9. Gender, age and extent of ST segment depression were not related to the occurrence of cardiac events.Thus, exercise ECG testing is not the technique of choice to detect silent restenosis after coronary angioplasty of single vessel coronary artery disease. An abnormal exercise test result and angiographic evidence of restenosis had only limited value in predicting long-term outcome in this patient group

Hypthesis and theory

Seabirds are amongst the most mobile of all animal species and spend large amounts of their lives at sea. They cross vast areas of ocean that appear superficially featureless, and our understanding of the mechanisms that they use for navigation remains incomplete, especially in terms of available cues. In particular, several large-scale navigational tasks, such as homing across thousands of kilometers to breeding sites, are not fully explained by visual, olfactory or magnetic stimuli. Low-frequency inaudible sound, i.e., infrasound, is ubiquitous in the marine environment. The spatio-temporal consistency of some components of the infrasonic wavefield, and the sensitivity of certain bird species to infrasonic stimuli, suggests that infrasound may provide additional cues for seabirds to navigate, but this remains untested. Here, we propose a framework to explore the importance of infrasound for navigation. We present key concepts regarding the physics of infrasound and review the physiological mechanisms through which infrasound may be detected and used. Next, we propose three hypotheses detailing how seabirds could use information provided by different infrasound sources for navigation as an acoustic beacon, landmark, or gradient. Finally, we reflect on strengths and limitations of our proposed hypotheses, and discuss several directions for future work. In particular, we suggest that hypotheses may be best tested by combining conceptual models of navigation with empirical data on seabird movements and in-situ infrasound measurements

The Classical-Map Hyper-Netted-Chain (CHNC) technique for inhomogeneous electron systems. Application to quantum dots

The Classical-map Hyper-Netted-Chain (CHNC) technique is a simple method of calculating quantum pair-distribution functions, spin-dependent energies, etc., of strongly-interacting {\it uniform} systems. We present CHNC calculations of charge densities and energies of {\it non-uniform} systems, viz., quantum dots, and compare with quantum Monte Carlo and density -functional results. Results for up to 210 electrons are reported.Comment: Latex manuscript and one figure (colour online). New calculations extending to 210 electrons are include

Two families of non-LTR retrotransposons, Syrinx and Daphne, from the Darwinulid ostracod, Darwinula stevensoni

Author Posting. © The Authors, 2005. This is the author's version of the work. It is posted here by permission of Elsevier B.V. for personal use, not for redistribution. The definitive version was published in Gene 371 (2006): 296-307, doi:10.1016/j.gene.2005.12.007.Two novel families of non-LTR retrotransposons, named Syrinx and Daphne, were cloned and characterized in a putative ancient asexual ostracod Darwinula stevensoni. Phylogenetic analysis reveals that Daphne is the founding member of a novel clade of non-LTR retroelements, which also contains newly described families from the sea urchin and the silkworm and forms a sister clade to L2-like elements. The Syrinx family of non-LTR retrotransposons exhibits evidence of relatively recent activity, manifested in high levels of sequence similarity between individual copies and a three- to ten-fold excess of synonymous substitutions, which is indicative of purifying selection. The Daphne family may have very few copies with intact open reading frames, and exhibits neutral within-family ratio of non-synonymous to synonymous substitutions. It can additionally be characterized by formation of inverted truncated head-to-head structures. All of these features make recent activity less likely than in the Syrinx family. Our results are discussed in light of the evolutionary consequences of long-term asexuality in general and in Darwinula stevensoni in particular.I.S. acknowledges funding from the EC (Marie-Curie grant BIO-4-CT-98-5086) and the Belgian OSTC (MO/36/005), and I.A. would like to thank the U.S. National Science Foundation

Exposure time to rivals and sensory cues affect how quickly males respond to changes in sperm competition threat

Phenotypic plasticity can increase fitness in rapidly changeable environments, but may be limited if the underlying mechanisms cause a lag between environmental change and individual response or if the information individuals receive is unreliable. Hence to understand the evolution of plasticity we need to assess whether individuals respond to fine-scale variation in environmental cues. In this study we used a Drosophila melanogaster fruit fly model to investigate factors that determine how quickly males alter their behaviour in response to changes in sperm competition cues. Male D. melanogaster respond to exposure to rival males prior to mating by extending mating duration and increasing ejaculate investment. We have previously shown that to build-up the response, males need about 24 h exposure to a rival. We reasoned that this time lag was necessary to increase ejaculate production, but this physiological limitation should not apply when moving from high- to low-competition environments; hence we predicted that males should immediately decrease their investment when competition is removed. Here we tested this by measuring how long rival-exposed males maintained an extended mating duration after removal of the rival. We assessed how exposure time and sensory information affected the speed of change in behavioural state. Males maintained extended mating duration for hours after a rival was removed, but this was dependent on time of exposure to a rival. Furthermore, although sensory-impaired males were able to respond to rivals, the time required for the response to build and diminish depended on males possessing their full sensory repertoire. Our results suggest that males use exposure time and multiple sensory cues to assess whether the threat of sperm competition is transient (so unlikely to translate into realized competition) or sustained (requiring a response). Therefore, time lags between environmental changes and responses may buffer animals against making hasty decisions in fluctuating environments

Systematic quantification of gene interactions by phenotypic array analysis

A phenotypic array method, developed for quantifying cell growth, was applied to the haploid and homozygous diploid yeast deletion strain sets. A growth index was developed to screen for non-additive interacting effects between gene deletion and induced perturbations. From a genome screen for hydroxyurea (HU) chemical-genetic interactions, 298 haploid deletion strains were selected for further analysis. The strength of interactions was quantified using a wide range of HU concentrations affecting reference strain growth. The selectivity of interaction was determined by comparison with drugs targeting other cellular processes. Bio-modules were defined as gene clusters with shared strength and selectivity of interaction profiles. The functions and connectivity of modules involved in processes such as DNA repair, protein secretion and metabolic control were inferred from their respective gene composition. The work provides an example of, and a general experimental framework for, quantitative analysis of gene interaction networks that buffer cell growth

Ploidy variation in fungi: Polyploidy, aneuploidy, and genome evolution

The ability of an organism to replicate and segregate its genome with high fidelity is vital to its survival and for the production of future generations. Errors in either of these steps (replication or segregation) can lead to a change in ploidy or chromosome number. While these drastic genome changes can be detrimental to the organism, resulting in decreased fitness, they can also provide increased fitness during periods of stress. A change in ploidy or chromosome number can fundamentally change how a cell senses and responds to its environment. Here, we discuss current ideas in fungal biology that illuminate how eukaryotic genome size variation can impact the organism at a cellular and evolutionary level. One of the most fascinating observations from the past 2 decades of research is that some fungi have evolved the ability to tolerate large genome size changes and generate vast genomic heterogeneity without undergoing canonical meiosis

Infrasound as a cue for seabird navigation

Seabirds are amongst the most mobile of all animal species and spend large amounts of their lives at sea. They cross vast areas of ocean that appear superficially featureless, and our understanding of the mechanisms that they use for navigation remains incomplete, especially in terms of available cues. In particular, several large-scale navigational tasks, such as homing across thousands of kilometers to breeding sites, are not fully explained by visual, olfactory or magnetic stimuli. Low-frequency inaudible sound, i.e., infrasound, is ubiquitous in the marine environment. The spatio-temporal consistency of some components of the infrasonic wavefield, and the sensitivity of certain bird species to infrasonic stimuli, suggests that infrasound may provide additional cues for seabirds to navigate, but this remains untested. Here, we propose a framework to explore the importance of infrasound for navigation. We present key concepts regarding the physics of infrasound and review the physiological mechanisms through which infrasound may be detected and used. Next, we propose three hypotheses detailing how seabirds could use information provided by different infrasound sources for navigation as an acoustic beacon, landmark, or gradient. Finally, we reflect on strengths and limitations of our proposed hypotheses, and discuss several directions for future work. In particular, we suggest that hypotheses may be best tested by combining conceptual models of navigation with empirical data on seabird movements and in-situ infrasound measurements