Miracle-dz/UniFAR-FTUs huggingface dataset:
Onset of Feedback Reactions Underlying Vertebrate Rod Photoreceptor Light Adaptation

Light adaptation in vertebrate photoreceptors is thought to be mediated through a number of biochemical feedback reactions that reduce the sensitivity of the photoreceptor and accelerate the kinetics of the photoresponse. Ca2+ plays a major role in this process by regulating several components of the phototransduction cascade. Guanylate cyclase and rhodopsin kinase are suggested to be the major sites regulated by Ca2+. Recently, it was proposed that cGMP may be another messenger of light adaptation since it is able to regulate the rate of transducin GTPase and thus the lifetime of activated cGMP phosphodiesterase. Here we report measurements of the rates at which the changes in Ca2+ and cGMP are followed by the changes in the rates of corresponding enzymatic reactions in frog rod outer segments. Our data indicate that there is a temporal hierarchy among reactions that underlie light adaptation. Guanylate cyclase activity and rhodopsin phosphorylation respond to changes in Ca2+ very rapidly, on a subsecond time scale. This enables them to accelerate the falling phase of the flash response and to modulate flash sensitivity during continuous illumination. To the contrary, the acceleration of transducin GTPase, even after significant reduction in cGMP, occurs over several tens of seconds. It is substantially delayed by the slow dissociation of cGMP from the noncatalytic sites for cGMP binding located on cGMP phosphodiesterase. Therefore, cGMP-dependent regulation of transducin GTPase is likely to occur only during prolonged bright illumination.
Gestational thrombocytopaenia among pregnant women in Lagos, Nigeria

Background: Thrombocytopaenia is a common haematologic abnormality during pregnancy. Pregnant women with thrombocytopenia have a higher risk of bleeding excessively during or after childbirth, particularly if they need to have a caesarean section or other surgical intervention during pregnancy, labour or in the puperium. The aim of this study was to determine the prevalence of gestational thrombocytopaenia among pregnant women reporting for antenatal care at tertiary health care centres in Lagos. Materials and Methods: Platelet count was analyzed in 274 consecutive pregnant women who gave informed consent and 70 non-pregnant female staff of the hospitals. Platelet count was performed on each sample using the Sysmex KN-21N automated haematology analyzer. The study design was cross-sectional, proportions were analyzed for statistical significance with the chi-square, and Odds ratio was also calculated. Thrombocytopaenia is classically defined as a platelet count of less than 150 × 109/L.34 Counts from 100 to 150 × 109/L are considered mildly depressed, 50 to 100 × 109/L are moderately depressed and less than 50 × 109/L are severely depressed. Results: Thirty-four (13.5%) pregnant women were thrombocytopaenic compared with three (4.3%) non-pregnant women. This was statistically significant; P = 0.03; Odds ratio: 3.5 (95% CI 1.03-11.82). Out of the 37 pregnant women who were thrombocytopaenic, most of them (78%) had mild thrombocytopenia, only 6% had severe thrombocytopaenia. Conclusion: The prevalence of gestational thrombocytopaenia in this study was 13.5%. Although majority of the pregnant women had mild thrombocytopaenia, healthcare providers should screen all pregnant women routinely for thrombocytopaenia to avoid excessive bleeding during or after childbirth.
Informal Labor and the Efficiency Cost of Social Programs: Evidence from the Brazilian Unemployment Insurance Program

It is widely believed that the presence of a large informal sector increases the efficiency cost of social programs -- transfer and social insurance programs -- in developing countries. We evaluate such claims for policies that have been heavily studied in countries with low informality -- increases in unemployment insurance (UI) benefits. We introduce informal work opportunities into a canonical model of optimal UI that specifies the typical tradeoff between workers' need for insurance and the efficiency cost from distorting their incentives to return to a formal job. We then combine the model with evidence drawn from comprehensive administrative data to quantify the efficiency cost of increases in potential UI duration in Brazil. We find evidence of behavioral responses to UI incentives, including informality responses. However, because reemployment rates in the formal sector are low to begin with, most beneficiaries would draw the UI benefits absent behavioral responses, and only a fraction of the cost of (longer) UI benefits is due to perverse incentive effects. As a result, the efficiency cost is relatively low, and in fact lower than comparable estimates for the US. We reinforce this finding by showing that the efficiency cost is also lower in labor markets with higher informality within Brazil. This is because formal reemployment rates are even lower in those labor markets absent behavioral responses. In sum, the results go against the conventional wisdom, and indicate that efficiency concerns may even become more relevant as an economy formalizes.
We Are What We Eat: Women and Diet for Cardiovascular Health

In women, cardiovascular disease is highly prevalent and is costly in terms of mortality and morbidity. Healthcare providers should educate women about initiating and maintaining a cardiovascular-healthy diet as a cornerstone of primary and secondary prevention. The difficulty comes in determining the correct messaging regarding diet components. Women should routinely consume a diet known to prevent coronary heart disease, stroke, and other cardiovascular risk factors. Essential aspects of good nutrition for women include diets rich in fiber, whole grains, fresh fruits, vegetables, fish, nuts, antioxidants, minerals, vegetable protein, marine and plant omega-3 fatty acids, and vitamins of the B group. Some foods known to provide cardiac protection in women, such as potatoes and citrus fruit juices, may not be cardioprotective in men. Thus, it is important to continue research efforts in women to determine the best diet for cardiovascular health.
The Leishmania nicotinamidase is essential for NAD+ production and parasite proliferation

NAD+ is a central cofactor that plays important roles in cellular metabolism and energy production in all living cells. Genomics‐based reconstruction of NAD+ metabolism revealed that Leishmania protozoan parasites are NAD+ auxotrophs. Consequently, these parasites require assimilating NAD+ precursors (nicotinamide, nicotinic acid, nicotinamide riboside) from their host environment to synthesize NAD+ by a salvage pathway. Nicotinamidase is a key enzyme of this salvage pathway that catalyses conversion of nicotinamide (NAm) to nicotinic acid (Na), and that is absent in higher eukaryotes. We present here the biochemical and functional characterizations of the Leishmania infantum nicotinamidase (LiPNC1). Generation of Lipnc1 null mutants leads to a decrease in NAD+ content, associated with a metabolic shutdown‐like phenotype with an extensive lag phase of growth. Both phenotypes could be rescued by an add‐back construct or by addition of exogenous Na. In addition, Lipnc1 null mutants were unable to establish a sustained infection in a murine experimental model. Altogether, these results illustrate that NAD+ homeostasis is a fundamental component of Leishmania biology and virulence, and that NAm constitutes its main NAD+ source in the mammalian host. The crystal structure of LiPNC1 we solved allows now the design of rational inhibitors against this new promising therapeutic target.
The ATF site mediates downregulation of the cyclin A gene during contact inhibition in vascular endothelial cells

Contact inhibition mediates monolayer formation and withdrawal from the cell cycle in vascular endothelial cells. In studying the cyclins--key regulators of the cell cycle--in bovine aortic endothelial cells (BAEC), we found that levels of cyclin A mRNA decreased in confluent BAEC despite the presence of 10% fetal calf serum. We then transfected into BAEC a series of plasmids containing various lengths of the human cyclin A 5' flanking sequence and the luciferase gene. Plasmids containing 3,200, 516, 406, 266, or 133 bp of the human cyclin A promoter directed high luciferase activity in growing but not confluent BAEC. In contrast, a plasmid containing 23 bp of the cyclin A promoter was associated with a 65-fold reduction in activity in growing BAEC, and the promoter activities of this plasmid were identical in both growing and confluent BAEC. Mutation of the activating transcription factor (ATF) consensus sequence at bp -80 to -73 of the cyclin A promoter decreased its activity, indicating the critical role of the ATF site. We identified by gel mobility shift analysis protein complexes that bound to the ATF site in nuclear extracts from growing but not confluent BAEC and identified (with antibodies) ATF-1 as a binding protein in nuclear extracts from growing cells. Also, ATF-1 mRNA levels decreased in confluent BAEC. Taken together, these data suggest that the ATF site and its cognate binding proteins play an important role in the downregulation of cyclin A gene expression during contact inhibition.
Studies on Japanese Botryllid Ascidians. V. A New Species of the Genus Botrylloides Very Similar to Botrylloides simodensis in Morphology

Botrylloides simodensis, belonging to the family Botryllidae, is a common species on the rocky shore around Shimoda. Since this species was first reported in 1981, it has been noticed that some B. simodensis colonies have distinctly different ground colors and color patterns from colonies including type specimens (holotype and all of paratypes) of B. simodensis. However, as there is no remarkable difference among them in morphology other than the colonial colors and color patterns, they have been considered to belong to the same species. In the present work, colonies of B. simodensis sensu lato were divided into three groups, two major and one minor, based on their color-morphs and periods of sexual reproduction. In one of the major groups, B. simodensis sensu strict, the period of sexual reproduction was limited from July to September, as shown in the original description. The other major group engaged in sexual reproduction for much longer than the former group, and they frequently made clusters of vascular vessels and underwent vascular budding. Therefore, the group with the long period of sexual reproduction was described as a new species of the genus Botrylloides here. In addition, phylogenetic analysis based on mtDNA sequences of these groups indicated that each group had a peculiar sequence, and that they were genetically separated.
A sun holiday is a sunburn holiday

Many people take holidays in sunny locations with the express aim of sunbathing. This may result in sunburn, which is a risk factor for skin cancer. We investigated 25 Danish sun seekers during a week's holiday in the Canary Islands. The percentage of body surface area with sunburn was determined by daily skin examinations by the same observer. Erythemally effective ultraviolet radiation (UVR) exposure was assessed with time‐stamped personal dosimeters worn on the wrist. Volunteers reported their clothing cover and sunscreen use in diaries, and this information was used to determine body site‐specific UVR doses after adjustment for sun protection factor. Remarkably, we found that all volunteers sunburned at some point. The risk of sunburn correlated significantly with the adjusted body site‐specific UVR dose. Furthermore, there was also a significant relationship between the daily UVR dose and percentage of body surface area with sunburn. Our study shows that holiday UVR exposure results in a high risk of sunburn, which potentially increases the risk of skin cancer. Possible protection by melanogenesis is insufficient to protect against sunburn during a 1‐week sun holiday. Finally, our data clearly support a substantial skin cancer risk from sun holidays.
Understanding the Revolutions of 2011: Weakness and Resilience in Middle Eastern Autocracies

The wave of revolutions sweeping the Middle East bears a striking resemblance to previous political earthquakes. As in Europe in 1848, rising food prices and high unemployment have fueled popular protests from Morocco to Oman. As in Eastern Europe and the Soviet Union in 1989, frustration with closed, corrupt, and unresponsive political systems has led to defections among elites and the fall of once powerful regimes in Tunisia, Egypt, and perhaps Libya. Yet 1848 and 1989 are not the right analogies for this past winter's events. The revolutions of 1848 sought to overturn traditional monarchies, and those in 1989 were aimed at toppling communist governments. The revolutions of 2011 are fighting something quite differ ent: "sultanistic" dictatorships. Although such regimes often appear unshakable, they are actually highly vulnerable, because the very strategies they use to stay in power make them brittle, not resilient. It is no coincidence that although popular protests have shaken much of the Middle East, the only revolutions to succeed so far— those in Tunisia and Egypt—have been against modern sultans. For a revolution to succeed, a number of factors have to come together. The government must appear so irremediably unjust or inept that it is widely viewed as a threat to the country's future; elites (especially in the military) must be alien ated from the state and no longer willing to defend it; a broad-based section of the population, spanning ethnic and religious groups and socioeconomic classes, must mobilize; and international powers must either refuse to step in to defend the government or constrain it from using maximum force to defend itself. Revolutions rarely triumph because these conditions rarely coincide. This is especially the case in traditional monar chies and one-party states, whose leaders often manage to maintain popular support by making appeals to respect for royal tradition or nationalism. Elites, who are often enriched by such governments,
Elimination of levofloxacin in critically ill patients with renal failure: influence of continuous veno-venous hemofiltration.

OBJECTIVES Pharmacokinetic data on levofloxacin in critically ill patients are sparse and conflicting. Aim of the study was to assess the clearance of levofloxacin in critically ill patients treated with continuous veno-venous hemofiltration (CVVH). METHODS Pharmacokinetics of levofloxacin were studied in 11 critically ill patients. Four patients were treated with CVVH because of renal failure, 4 patients had moderately impaired renal function but were not on hemofiltration, and 3 patients had approximately normal renal function. Patients received 0.5 g levofloxacin infused over 0.5 hours. Plasma levels of levofloxacin were determined by HPLC and pharmacokinetic parameters were calculated using a non-compartmental model. RESULTS Levofloxacin clearance in critically ill patients with approximately normal renal function was similar to that in healthy subjects. In critically ill patients with impaired renal function not on CVVH, mean half-life was prolonged by a factor of about 3 (20-25 hours). The mean residence time and the volume of distribution were also increased. In renal failure treated with CVVH, a wide variability in pharmacokinetics was seen. The half-life was about 30 hours and the mean levofloxacin clearance was raised by a factor of 2. The area under the concentration-time curve was reduced by hemofiltration, while the volume of distribution was increased. There was a positive correlation between blood flow through the hemofilter and levofloxacin clearance. Variable amounts of the drug were recovered from the hemofilter. Most plasma levels, however, were in the therapeutic range and drug accumulation to toxic plasma concentrations was not observed in renal failure patients undergoing CVVH and receiving single daily administration of 0.5 g of levofloxacin i.v. CONCLUSIONS During CVVH using polysulfone membrane hemofilters, plasma concentrations of levofloxacin are not easily predictable. Levofloxacin clearance may be affected by binding to secondary membranes formed in hemofilters during CVVH and blood flow rates have a significant impact on the pharmacokinetics of levofloxacin.
An overview and comparison of various refrigeration methods for microelectronics cooling

Small-scale refrigerators, termed mesoscale refrigerators, are possible cooling solutions for high-power microelectronics. The performance of mesoscale refrigerators has not yet been experimentally demonstrated, although a recent theoretical model indicated that at temperatures near room temperature and above, a vapor compression refrigerator may compete successfully with a thermoelectric cooler having extremely high efficiency [1]. The present study proposes an overview and comparison between several alternative refrigeration methods used to actively cool the electronic components in a power microelectronics system. Three systems are evaluated, namely a miniaturized classical mechanical vapor compression system using an off-the-shelf compressor, a miniaturized system with ejector used for vapor compression, and finally a miniaturized refrigeration system with absorption, designed for similar cooling powers. The efficiency and COP of each system will be evaluated, together with associated reliability and cost related issues. The specifics of all proposed systems are based on the optimized performance of the miniaturized components of the various refrigeration systems, designed to fit the smaller scale power electronics populating a printed circuit board (PCB) in a high-power microelectronics system. For all designs, an array of micro-channels is used for vaporizer/condenser units. Several components of the refrigeration system are thermally evaluated for cooling powers ranging from 20- 100 W, with direct application to high power telecom units. Several advantages and/or disadvantages of these refrigeration-based cooling methods are highlighted. The study is concluded by identifying the pros and cons of implementing such systems to real-life microelectronics applications.
Parental Incarceration During Childhood, Family Context, and Youth Problem Behavior Across Adolescence

Over the past several decades, the number of youth with parents in prison in the United States has increased substantially. Findings thus far indicate that they are a vulnerable group of children. Using prospective longitudinal data gathered as part of the population-based Linking the Interests of Families and Teachers (LIFT) randomized controlled trial, adolescents who had an incarcerated parent during childhood are compared to those who did not across four key domains: family social advantage, parent health, the parenting strategies of families, and youth externalizing behavior and serious delinquency. Past parental incarceration was associated with lower family income, parental education, parental socioeconomic status, and parental health, and with higher levels of parental depression, inappropriate and inconsistent discipline, youth problem behaviors and serious delinquency. The effect sizes for significant associations were small to moderate.
Radial distribution of tocopherols in rhesus monkey retina and retinal pigment epithelium-choroid.

PURPOSE To map vitamin E as a function of distance from the foveal center in the primate retina and retinal pigment epithelium (RPE)-choroid. METHODS Eyecups from rhesus monkeys were dissected with circular trephines so that the innermost disc, centered on the fovea, was in the center of a series of concentric rings. Two different types of dissection were performed. For one type, the authors used circular trephines with diameters of 1, 4, 8, and 10 mm (1,4-D), whereas for the other type the diameters were 2, 5, 8, and sometimes 10 mm (2,5-D). When possible, the neural retina was separated from the RPE-choroid. Tissues were analyzed for vitamin E, retinyl palmitate, and protein. RESULTS Surface area, volume, and protein were used as indexes of the amount of tissue analyzed. Distributions of vitamin E in neural retina were dependent on the tissue metric used and type of dissection performed. However, regardless of the tissue metric used, the central 1-mm disc of the 1,4-D was, on average, higher in vitamin E content than was the central 2-mm disc of the 2,5-D. This was particularly true when volume was the tissue metric. From the average values of vitamin E in a series of concentric discs, a composite plot of the vitamin E concentration in the neural retina was generated that took into consideration both types of dissection. That plot displayed a local maximum in the fovea and then precipitously declined to a minimum in the region between 0.5 and 1.0 mm eccentricity (near the foveal crest); at greater eccentricities, the vitamin E concentration rose to a value similar to that in the fovea, i.e., the composite plot indicated that vitamin E has a V-shaped distribution in the central neural retina. Vitamin E distribution in the RPE-choroid, with surface area as the tissue metric, also was measured. For this tissue, the foveal region displayed a local maximum. CONCLUSIONS By combining the results of two different types of dissection, the authors found that in the neural retina, vitamin E displayed a minimum near the foveal crest. This minimum correlated anatomically with the site at which areolar (geographic) atrophy frequently occurs in retinal pigment epithelial cells in the human disease, age-related macular degeneration.
Boundary Completion, Contrast Polarity, and the Perception of Illusory Tilt

What we perceive as a unitary object can be the result of integrative processes that generate a whole from parts. Although this issue of visual perception has been widely explored, recent experimental findings demonstrate that our knowledge is still incomplete. In particular, the question whether contour binding is affected by the sign of contrast (contrast polarity) across edges requires more in-depth examination. Here we show the effects of edge bindings that originate from the merging of laterally displaced edges with the same contrast polarity. We have studied a particular context in which such effects may emerge: a checkerboard with a series of alternated dark and light shapes superimposed on the corners of the squares. The phenomenal observations and experimental findings support the theories according to which boundary completions are originated by phenomena of edge propagation within a ‘field of completion’ (eg Shipley and Kellman, 2003 Perception 32 985–999) adjacent to an edge ending. Our findings conform to the Shipley and Kellman theory that boundary completion results from the interaction of edges as well as from edges and shapes lacking in oriented contours, the latter serving as ‘receiving units’, anchoring the paths of activations generated by oriented edges. We propose to integrate this theory with the hypothesis that interactions sensitive to the contrast sign generate conjunction paths of edges that alter their perceived orientation. Based on this perspective we propose an alternative account for the Cafe Wall illusion that can be extended to other phenomena of orientation misperception and to a Cafe Wall inversion effect that has not been observed previously.
Funding Costs, Funding Strategies

The economic value of derivatives depends on the funding costs encountered by the issuer. In this paper we derive general relations between the costs of running specific funding strategies while the issuer is alive and the resulting windfalls or shortfalls upon the issuer default. This gives rise to generalisations to the classical bilateral CVA adjustment that include the cost of running specific funding strategies and sets the stage to discuss ways to mitigate these effects. We give practical examples of different funding strategies and their resulting funding cost (FCA) and funding value adjustments (FVA).