A HEDONIC APPROACH TO URBAN WETLAND VALUATION

Land Economics/Use,

The fundamental equations of change in statistical ensembles and biological populations

A recent article in Nature Physics unified key results from thermodynamics, statistics, and information theory. The unification arose from a general equation for the rate of change in the information content of a system. The general equation describes the change in the moments of an observable quantity over a probability distribution. One term in the equation describes the change in the probability distribution. The other term describes the change in the observable values for a given state. We show the equivalence of this general equation for moment dynamics with the widely known Price equation from evolutionary theory, named after George Price. We introduce the Price equation from its biological roots, review a mathematically abstract form of the equation, and discuss the potential for this equation to unify diverse mathematical theories from different disciplines. The new work in Nature Physics and many applications in biology show that this equation also provides the basis for deriving many novel theoretical results within each discipline

Hysteroscopy for treating subfertility associated with suspected major uterine cavity abnormalities

Background : Observational studies suggest higher pregnancy rates after the hysteroscopic removal of endometrial polyps, submucous fibroids, uterine septum or intrauterine adhesions, which are detectable in 10% to 15% of women seeking treatment for subfertility. Objectives : To assess the effects of the hysteroscopic removal of endometrial polyps, submucous fibroids, uterine septum or intrauterine adhesions suspected on ultrasound, hysterosalpingography, diagnostic hysteroscopy or any combination of thesemethods inwomenwith otherwise unexplained subfertility or prior to intrauterine insemination (IUI), in vitro fertilisation (IVF) or intracytoplasmic sperm injection (ICSI). Search methods : We searched theCochraneMenstrualDisorders and Subfertility SpecialisedRegister (8 September 2014), theCochrane Central Register of Controlled Trials (The Cochrane Library 2014, Issue 9), MEDLINE (1950 to 12 October 2014), EMBASE (inception to 12 October 2014), CINAHL (inception to 11 October 2014) and other electronic sources of trials including trial registers, sources of unpublished literature and reference lists. We handsearched the American Society for Reproductive Medicine (ASRM) conference abstracts and proceedings (from January 2013 to October 2014) and we contacted experts in the field. Selection criteria : Randomised comparisons between operative hysteroscopy versus control in women with otherwise unexplained subfertility or undergoing IUI, IVF or ICSI and suspected major uterine cavity abnormalities diagnosed by ultrasonography, saline infusion/ gel instillation sonography, hysterosalpingography, diagnostic hysteroscopy or any combination of these methods. Primary outcomes were live birth and hysteroscopy complications. Secondary outcomes were pregnancy and miscarriage. Data collection and analysis : Two review authors independently assessed studies for inclusion and risk of bias, and extracted data. We contacted study authors for additional information. Main results : We retrieved 12 randomised trials possibly addressing the research questions. Only two studies (309 women) met the inclusion criteria. Neither reported the primary outcomes of live birth or procedure related complications. In women with otherwise unexplained subfertility and submucous fibroids there was no conclusive evidence of a difference between the intervention group treated with hysteroscopic myomectomy and the control group having regular fertility-oriented intercourse during 12 months for the outcome of clinical pregnancy. A large clinical benefit with hysteroscopic myomectomy cannot be excluded: if 21% of women with fibroids achieve a clinical pregnancy having timed intercourse only, the evidence suggests that 39% of women (95% CI 21% to 58%) will achieve a successful outcome following the hysteroscopic removal of the fibroids (odds ratio (OR) 2.44, 95% confidence interval (CI) 0.97 to 6.17, P = 0.06, 94 women, very low quality evidence). There is no evidence of a difference between the comparison groups for the outcome of miscarriage (OR 0.58, 95% CI 0.12 to 2.85, P = 0.50, 30 clinical pregnancies in 94 women, very low quality evidence). The hysteroscopic removal of polyps prior to IUI can increase the chance of a clinical pregnancy compared to simple diagnostic hysteroscopy and polyp biopsy: if 28% of women achieve a clinical pregnancy with a simple diagnostic hysteroscopy, the evidence suggests that 63% of women (95% CI 50% to 76%) will achieve a clinical pregnancy after the hysteroscopic removal of the endometrial polyps (OR 4.41, 95% CI 2.45 to 7.96, P < 0.00001, 204 women, moderate quality evidence). Authors' conclusions : A large benefit with the hysteroscopic removal of submucous fibroids for improving the chance of clinical pregnancy in women with otherwise unexplained subfertility cannot be excluded. The hysteroscopic removal of endometrial polyps suspected on ultrasound in women prior to IUI may increase the clinical pregnancy rate. More randomised studies are needed to substantiate the effectiveness of the hysteroscopic removal of suspected endometrial polyps, submucous fibroids, uterine septum or intrauterine adhesions in women with unexplained subfertility or prior to IUI, IVF or ICSI

The Internal Circadian Clock Increases Hunger and Appetite in the Evening Independent of Food Intake and Other Behaviors

Objective: Despite the extended overnight fast, paradoxically, people are typically not ravenous in the morning and breakfast is typically the smallest meal of the day. Here we assessed whether this paradox could be explained by an endogenous circadian influence on appetite with a morning trough, while controlling for sleep/wake and fasting/feeding effects. Design and Methods We studied 12 healthy non-obese adults (6 male; age, 20–42 year) throughout a 13-day laboratory protocol that balanced all behaviors, including eucaloric meals and sleep periods, evenly across the endogenous circadian cycle. Participants rated their appetite and food preferences by visual analog scales. Results: There was a large endogenous circadian rhythm in hunger, with the trough in the biological morning (8 AM) and peak in the biological evening (8 PM; peak-to-trough amplitude=17%; P=0.004). Similarly phased significant endogenous circadian rhythms were present in appetite for sweets, salty and starchy foods, fruits, meats/poultry, food overall, and for estimates of how much food participants could eat (amplitudes 14–25%; all P < 0.05). Conclusions: In people who sleep at night, the intrinsic circadian evening peak in appetite may promote larger meals before the fasting period necessitated by sleep. Furthermore, the circadian decline in hunger across the night would theoretically counteract the fasting-induced hunger increase that could otherwise disrupt sleep

Maladaptation and the paradox of robustness in evolution

Background. Organisms use a variety of mechanisms to protect themselves against perturbations. For example, repair mechanisms fix damage, feedback loops keep homeostatic systems at their setpoints, and biochemical filters distinguish signal from noise. Such buffering mechanisms are often discussed in terms of robustness, which may be measured by reduced sensitivity of performance to perturbations. Methodology/Principal Findings. I use a mathematical model to analyze the evolutionary dynamics of robustness in order to understand aspects of organismal design by natural selection. I focus on two characters: one character performs an adaptive task; the other character buffers the performance of the first character against perturbations. Increased perturbations favor enhanced buffering and robustness, which in turn decreases sensitivity and reduces the intensity of natural selection on the adaptive character. Reduced selective pressure on the adaptive character often leads to a less costly, lower performance trait. Conclusions/Significance. The paradox of robustness arises from evolutionary dynamics: enhanced robustness causes an evolutionary reduction in the adaptive performance of the target character, leading to a degree of maladaptation compared to what could be achieved by natural selection in the absence of robustness mechanisms. Over evolutionary time, buffering traits may become layered on top of each other, while the underlying adaptive traits become replaced by cheaper, lower performance components. The paradox of robustness has widespread implications for understanding organismal design

High-Resolution X-Ray Spectroscopy of the Accretion Disk Corona Source 4U 1822-37

We present a preliminary analysis of the X-ray spectrum of the accretion disk corona source, 4U 1822-37, obtained with the High Energy Transmission Grating Spectrometer onboard the Chandra X-ray Observatory. We detect discrete emission lines from photoionized iron, silicon, magnesium, neon, and oxygen, as well as a bright iron fluorescence line. Phase-resolved spectroscopy suggests that the recombination emission comes from an X-ray illuminated bulge located at the predicted point of impact between the disk and the accretion stream. The fluorescence emission originates in an extended region on the disk that is illuminated by light scattered from the corona.Comment: 12 pages, 6 figures; Accepted for publication in ApJ Letter