bluuebunny/crossref_metadata_2025 huggingface dataset:
A Comparison of International and Domestic Sources of Global Governance Dynamics
Authors: Bernauer Thomas , Kalbhenn Anna , Koubi Vally , Spilker Gabriele
Published: June 2010

Existing empirical models of international co-operation emphasize domestic determinants, although virtually all theories of international relations focus on interdependencies between countries. This article examines how much states’ linkages with the international system, relative to domestic factors, such as income and democracy, influence the dynamics of global governance efforts. To this end, we study the ratification behaviour of 180 countries vis-à-vis 255 global environmental treaties. Except for integration into the world economy, which affects co-operative behaviour negatively, our results show that international factors have a stronger and more positive impact on cooperative behaviour than domestic factors. This implies that Galton’s advice not to examine the effects of internal and external variables in isolation is also useful in the study of international politics.
DNA-based discrimination and frequency of phytoplasma infection in the two hawthorn-feeding species, Cacopsylla melanoneura and Cacopsylla affinis, in northwestern Italy
Authors: Tedeschi R. , Nardi F.
Published: June 2010

A molecular tool, focused on the mitochondrial Control Region (CR), was developed to discriminate the two hawthorn-feeding psyllid species, Cacopsylla melanoneura (Förster) and C. affinis (Löw), and to estimate their frequencies in mixed populations. The test was carried out in paired and single-tube amplifications and validated analysing 52 male specimens previously determined by morphological analysis. The frequencies of the two species in mixed populations in the Aosta Valley (northwestern Italy) were analysed. The presence and type of 16SrX-group phytoplasmas was detected by nested PCR and RFLP tests in both species. C. melanoneura was the predominant species (86.5%; 80.4–91.2 CI); of these, 0.9% of the samples were positive for ‘Ca. Phytoplasma mali’ and 1.8% for ‘Ca. Phytoplasma pyri’. One of 21 specimens of C. affinis was positive for ‘Ca. Phytoplasma pyri’. The test also allowed us to identify two genetic variants of C. melanoneura, depending on the presence or absence of a 56 bp indel; these were named WI (with indel) and WOI (without indel), respectively. Further analyses were carried out on C. melanoneura specimens collected in apple orchards at six different locations in northern Italy where different levels of transmission efficiency have been described. Our preliminary observations suggest that some differences might exist between the two genetic variants in their ability to transmit phytoplasmas and to colonise different host plants.
Association between the squat lobsterGastroptychus formosusand cold-water corals in the North Atlantic
Authors: Le Guilloux E. , Hall-Spencer J.M. , Söffker M.K. , Olu K.
Published: June 2010

Although there are no previous descriptions of the habits of chirostylids in the North Atlantic, it is likely that species in the generaUroptychus,EumunidaandGastroptychushave close ecological ties with deep-sea corals since they have all been recorded in trawl samples containing corals from >200 m depth. We analysedin situdistribution ofGastroptychus formosusand potential hosts using a ROV at a range of north-eastern Atlantic sites and found that this species forms a close association with deep-sea corals that resembles the chirostylid–anthozoan associations reported in shallow Indo-Pacific waters. We update the known distribution forG. formosus, confirming that it is an amphiatlantic species that occurs along the Mid-Atlantic Ridge at least as far south as the Azores and along continental margins from the Canary Islands to Scotland at depths of 600–1700 m. The adults have very specific habitat preferences, being only found on gorgonian and antipatharian corals with a strong preference forLeiopathessp. as a host. This highly restricted habitat preference is likely to render chirostylids vulnerable to the impacts of demersal fishing both directly, as by-catch, and indirectly through habitat loss.
The hydrothermal vent community of a new deep-sea field, Ashadze-1, 12°58′N on the Mid-Atlantic Ridge
Authors: Fabri M-C. , Bargain A. , Briand P. , Gebruk A. , Fouquet Y. , Morineaux M. , Desbruyeres D.
Published: June 2010

Ashadze-1 (12° 58′N 44° 51′W, 4080 m) on the Mid-Atlantic Ridge (MAR) is the deepest known active hydrothermal vent field. The first observations on this site were numerous clear and black smokers and surprisingly few known symbiotic species dominant in other vent areas on the MAR. The species most abundant at Ashadze-1 are those usually found at the periphery of hydrothermal communities: sea-anemones Maractis rimicarivora and chaetopterid polychaetes Phyllochaetopterus sp. nov. This study comprised site mapping and faunal sampling and Ashadze-1 was completely mapped by using the remote operated vehicle ‘Victor 6000’ and a new high resolution tool available for deep-sea research. A photo-mapping survey was carried out with a long range optical black and white camera. Digitization of substrata and sea-anemones visible on the images was performed by GIS. Spatial distribution of Ma. rimicarivora was distinguished by high densities of 32 ind.m−2 on the western side of the main smoker area. Submersible sampling operations allowed taxonomic identification within a 200 × 110 m area. Carbon, nitrogen and sulphur isotopic ratios were measured in four dominant species to identify their trophic position. The present paper gives the complete maps and describes the faunal community of the Ashadze-1 vent field. The results obtained led us to consider this site as an ecosystem in its declining stage. Finally we compare the similarities of this community to other hydrothermal communities on the northern MAR.
Flavonoids as anti-inflammatory agents
Authors: Serafini Mauro , Peluso Ilaria , Raguzzini Anna
Published: June 2010

Epidemiological evidence suggests that a high intake of plant foods is associated with lower risk of chronic diseases. However, the mechanism of action and the components involved in this effect have not been identified clearly. In recent years, the scientific community has agreed to focus its attention on a class of secondary metabolites extensively present in a wide range of plant foods: the flavonoids, suggested as having different biological roles. The anti-inflammatory actions of flavonoidsin vitroor in cellular models involve the inhibition of the synthesis and activities of different pro-inflammatory mediators such as eicosanoids, cytokines, adhesion molecules and C-reactive protein. Molecular activities of flavonoids include inhibition of transcription factors such as NF-κB and activating protein-1 (AP-1), as well as activation of nuclear factor-erythroid 2-related factor 2 (Nrf2). However, thein vitroevidence might be somehow of limited impact due to the non-physiological concentrations utilized and to the fact thatin vivoflavonoids are extensively metabolized to molecules with different chemical structures and activities compared with the ones originally present in the food. Human studies investigating the effect of flavonoids on markers of inflammation are insufficient, and are mainly focused on flavonoid-rich foods but not on pure molecules. Most of the studies lack assessment of flavonoid absorption or fail to associate an effect on inflammation with a change in circulating levels of flavonoids. Human trials with appropriate placebo and pure flavonoid molecules are needed to clarify if flavonoids represent ancillary ingredients or key molecules involved in the anti-inflammatory properties of plant foods.
The importance of fatty liver disease in clinical practice
Authors: Cobbold Jeremy F. L. , Anstee Quentin M. , Taylor-Robinson Simon D.
Published: June 2010

The worldwide obesity epidemic over the last 20 years has led to a dramatic increase in the prevalence of non-alcoholic fatty liver disease, the hepatic manifestation of the metabolic syndrome. Estimates of prevalence vary depending on the population studied and the methods used to assess hepatic fat content, but are commonly quoted as between 10 and 30% of the adults in the Western hemisphere. Fatty liver develops when fatty acid uptake and synthesis in the liver exceeds fatty acid oxidation and export as TAG. Studies of pathogenesis point to insulin resistance, lipotoxicity, oxidative stress and chronic inflammation being central to the development and progression of the disease. A proportion of individuals with fatty liver develop progressive disease, though large prospective longitudinal studies are lacking. Nevertheless, fatty liver is associated with increased all-cause and liver-related mortality compared with the general population. Management of fatty liver centres around lifestyle and dietary measures to induce controlled and sustained weight loss. Management of cardiovascular risk factors aims to reduce mortality, while certain dietary interventions have been shown to reduce steatosis and inflammation. Specific pharmacological treatments also show promise, but their use is not widespread. A multi-system and multi-disciplinary approach to the management of this disorder is proposed.
On Philosophy's (lack of) Progress: From Plato to Wittgenstein (and Rawls)
Authors: Read R.
Published: June 2010

I argue that the type of progress exhibited by philosophy is not that exhibited by science (as analysed e.g. by Thomas Kuhn), but rather is akin to the kind of progress exhibited (say) be someone becoming ‘older and wiser’. However, as actually-existing philosophy has gotten older, it has not always gotten wiser. As an illustration, I consider Rawls's conception of justification. I argue that Rawls's notion of what it is to have a philosophical justification exhibits no progress at all from Euthyphro's. In fact, drawing on a remark of Wittgenstein's, I suggest that Rawls's conception is inferior to the situation as depicted in Plato's famous dialogue – because at least in the case of Plato's Euthyphro, there is no illusion of justification.
The Ibāḍī “stages of religion” re-examined: Tracing the history of the Masālik al-Dīn
Authors: Gaiser Adam
Published: June 2010

With few exceptions, scholarly presentations of the Ibāḍī “stages of religion” (masālik al-dīn) and their corresponding Imāms (i.e. imām al-ẓuhūr, imām al-difāʿ, imām al-shirā', and imām al-kitmān) propose a simplified overview of the institution that is based on post-Ibāḍī renaissance thought on the Imāmate. This paper investigates the pre-renaissance usages of the masālik al-dīn by comparing sixth/twelfth-century Arabian and North African Ibāḍī texts on the subject. It demonstrates that Eastern and Western Ibāḍīs manipulated the concepts central to the later masālik al-dīn ideal to reflect the particular needs of each respective community. While the articulations of the masālik al-dīn differed according to region, they simultaneously utilized a similar vocabulary. This convergence implies an earlier and inherited conceptual system (most likely from the earliest Basran Ibāḍī umma) that was adapted in the medieval period to fulfil the unique needs of each community.
Issues of causation in homicide decisions of the Qing Board of Punishments from the eighteenth and nineteenth centuries
Authors: MacCormack Geoffrey
Published: June 2010

This paper explores in decisions of the Qing Board of Punishments the importance of the identification of the “cause of death” for the allocation of liability in cases of homicide. The Board's preoccupation with the issue of causation is discussed through its use of three formulae which express in different ways the causal link between the elements in the chain of causation culminating in death:yin/you … so zhi(“cause … as a result of which”),zui zuo so you/yin(“offence liable that which causes”), andzhaoxin(“beginning of the trouble”). Some remarks are added on the relationship between the concepts of “causation” and “fault” in the historical development of the traditional Chinese law of homicide.
Hpo Hlaing on Buddhist law
Authors: Huxley Andrew
Published: June 2010

This article introduces an English version (translator unknown) of a Burmese law report: Judge Hpo Hlaing's ruling in Ma Hla v. Ma Wa, delivered in Mandalay in 1877. The judgement contains a paragraph dealing with the sources of Buddhist Law which appears to be a riposte to work published earlier that year in Lower Burma. That the judge was Burma's leading political philosopher gives special resonance to his views on law. His list of five law reports from the Pali canon and related texts is of interest. A reading is advanced in which the five cases link to Burmese ideas about legal pluralism.
Time course of meiotic spindle development in MII oocytes
Authors: Kilani Suha , Cooke Simon , Chapman Michael
Published: June 2010

The aim of this study was to examine changes in meiotic spindle morphology over time to potentially optimize timing for ICSI. Using polarized light microscopy, images of MII oocytes were captured after retrieval of oocytes in stimulated cycles at six time intervals in culture: 36–36.5 h, 36.5–37.0 h, 38–38.5 h, 39–39.5 h, 40–40.5 h and 40.5–41 h post hCG. Captured images were analysed for spindle presence and their retardance. Results showed that spindles were detected in 58% (45/78) of oocytes at 36–36.5 h. This percentage rose to a peak (96% vs. 58%, p < 0.001) at 39–39.5 h and stabilized between 39–40.5 h post trigger then significantly declined at 40.5–41 h post hCG (96% vs. 77%, p < 0.001). Average spindle retardance increased from 36–36.5 h (1.8 ± 0.7 nm) until it peaked at 39–40.5 h (3.8 ± 0.8 nm, p < 0.0001) and then declined significantly after 40.5–41 h (3.2 ± 0.9 nm, p = 0.0001). These results show that the meiotic spindle appearance is time dependent with the majority of oocytes having detectable spindles and highest retardance between 39–40.5 h post hCG under currently used stimulation protocol after which they start to disaggregate. 39–40.5 h post hCG may be the optimal time for ICSI.
Optimization of artificial fertilization in the stinging catfish Heteropneustes fossilis (Bloch)
Authors: Christopher J. Godwin , Murugesan A.G. , Sukumaran N.
Published: June 2010

Determination of optimum sperm requirement in artificial breeding helps to improve the fertilization efficiency, sperm economy and minimize the sacrificing of males for milt. Quantification of sperm cells was done by spectrophotometer at 420 nm followed by haemocytometer counting. Best correlation (r2 = 0.97) was recorded. The minimum number of sperm required for optimal fertilization success in Heteropneustes fossilis was determined. An average fertilization success of 78–93% was recorded at 8 × 103 to 8 × 107 sperm per egg. The optimum contact duration of gametes was 5 minutes. The highest fertilization rate of 98.18% was recorded at 8 × 107 spermatozoa.egg−1.
Ultraviolet radiation and handling medium osmolarity affect chimaerism success in zebrafish
Authors: Francisco-Simão M. , Cardona-Costa J. , Pérez-Camps M. , García-Ximénez F.
Published: June 2010

The effects of a predefined ultraviolet radiation dose (0.529 mW/cm2for 30s) together with two different micromanipulation medium osmolarities (30 mOsm/kg vs 300 mOsm/kg) were tested on embryo survival at different developmental stages and on the somatic (skin) and germ-line chimaerism rates. Somatic (13%, 6/47 adults) and germ-line chimaerism (50% pigmented F1 larvae) were detected only in the UV-treated recipient embryos micromanipulated in a 300 mOsm/kg medium. From the results obtained, we concluded that the conditions cited above were the most suitable to improve somatic and germ-line chimaerism rates in zebrafish.
Activation of AMP-activated protein kinase may not be involved in AICAR- and metformin-mediated meiotic arrest in bovine denuded and cumulus-enclosed oocytes in vitro
Authors: Bilodeau-Goeseels Sylvie , Panich Paul L. , Kastelic John P.
Published: June 2010

The adenosine monophosphate-activated protein kinase (AMPK) activators, 5′-aminoimidazole-4-carboxamide 1-β-d-ribofuranoside (AICAR) and metformin (MET), inhibit resumption of meiosis in bovine cumulus-enclosed oocytes (CEO) and denuded oocytes (DO). The objectives of this study were to: (1) examine the effects of AMPK inhibitors on bovine oocyte meiosis in vitro; and (2) determine if AICAR or MET activates oocyte and/or cumulus cell AMPK. The AMPK inhibitor compound C (CC; 0.5, 1, 5, and 10 μM) did not reverse the inhibitory effects of AICAR (1 mM) and MET (2 mM) on bovine oocyte meiosis. Additionally, CC (5 and 10 μM) inhibited meiosis (p < 0.05) in CEO and DO cultured for 7 h. Okadaic acid (1 μM) reversed the inhibitory effect of MET (2 mM) and CC (5 μM; p < 0.05) but not of AICAR (1 mM). Phosphorylation of the alpha subunit of AMPK on Thr172 is required for activation. Based on western blot analysis, AICAR, MET and CC did not affect Thr172 phosphorylation levels in DO and oocytes from complexes (p > 0.05). In cumulus cells, Thr172 phosphorylation decreased after 3 h of culture (p < 0.05), regardless of the presence of AMPK modulators in the culture medium. Higher concentrations of AICAR (2 mM) and MET (10 mM) did not affect Thr172 phosphorylation, but phosphorylation on Ser79 of ACC, a substrate of AMPK, was increased in response to MET (p < 0.05). In conclusion, we inferred that the inhibitory effect of AICAR and MET on bovine oocyte meiosis was probably not mediated through activation of AMPK. Moreover, these compounds probably inhibited meiosis through different pathways.
Does the Fear of Terrorists Trump the Fear of Persecution in Asylum Outcomes in the Post–September 11 Era?
Authors: Holmes Jennifer S. , Keith Linda Camp
Published: June 2010

Historically, U.S. asylum policy has reflected both an effort to provide safe haven for deserving asylum seekers and the intent to promote national security and domestic policy priorities. A growing body of empirical evidence suggests that asylum outcomes, at least in the aggregate, have been weighted more heavily by foreign policy considerations than humanitarian concerns. Since the mid 1990s, the United States government has reformed the asylum system in response to concerns of abuse by economic migrants, burgeoning caseloads, and national security threats. Although, as Davergne (2008) points out, “the most reviled of asylum seekers of the global era is the ‘economic refugee,’ under suspicion of fleeing poverty and poor prospects in search of a better life” rather than fleeing because of the fear of persecution (65), in the wake of terrorist attacks on the United States in 1993 and 2001, the fears of economic opportunists abusing the system have combined with the broader fear of potential terrorists gaining legal entry into the country through an overburdened asylum system. Since 1995, Congress has passed two major acts to reform the asylum process in reaction to these fears. Both the 1996 Illegal Immigration Reform and Immigrant Responsibility Act and the 2005 Real ID Act were passed to prevent economic migrants and individuals who may pose security risks from entering the country on false claims of asylum. Following September 11, the U.S. government has pursued prosecution for documents fraud among asylum applicants and aggressively enforced safe third country requirements. And, like our European counterparts, the United States has increasingly taken more deterrent and preventative actions to discourage asylum applicants from choosing it as a target for asylum and prevent potential applicants from reaching its ports of entry. Critics fear that the draconian measures adopted in response to these fears are overly broad and worry that worthy applicants have been turned away at the border or denied asylum with increasing frequency, thus leading them to face the real possibility of torture and other forms of persecution. In this article, we examine changes in U.S. asylum policy and whether the heightened security concerns after September 11 have significantly influenced the U.S. asylum process and outcomes in U.S. immigration courts.
THE BEHAVIOR OF THE SAVING RATE IN THE NEOCLASSICAL OPTIMAL GROWTH MODEL
Authors: Litina Anastasia , Palivos Theodore
Published: June 2010

This paper characterizes the saving rate in the Ramsey–Cass–Koopmans model analytically with a general production function when there exist both exogenous and endogenous growth. It points out conditions involving the share of capital and the elasticities of factor and intertemporal substitution under which the saving rate path to its steady-state value exhibits overshooting or undershooting or is monotonic. Simulations illustrate these interesting dynamics. The paper also identifies the general class of production functions that render the saving rate constant along the entire transition path and hence make the Ramsey–Cass–Koopmans model isomorphic to that of Solow and Swan.
Exhumation, crustal deformation, and thermal structure of the Nepal Himalaya derived from the inversion of thermochronological and thermobarometric data and modeling of the topography
Authors: Herman Frédéric , Copeland Peter , Avouac Jean‐Philippe , Bollinger Laurent , Mahéo Gweltaz , Le Fort Patrick , Rai Santaman , Foster David , Pêcher Arnaud , Stüwe Kurt , Henry Pierre
Published: June 2010

Two end‐member kinematic models of crustal shortening across the Himalaya are currently debated: one assumes localized thrusting along a single major thrust fault, the Main Himalayan Thrust (MHT) with nonuniform underplating due to duplexing, and the other advocates for out‐of‐sequence (OOS) thrusting in addition to thrusting along the MHT and underplating. We assess these two models based on the modeling of thermochronological, thermometric, and thermobarometric data from the central Nepal Himalaya. We complement a data set compiled from the literature with 114 40Ar/39Ar, 10 apatite fission track, and 5 zircon (U‐Th)/He thermochronological data. The data are predicted using a thermokinematic model (PECUBE), and the model parameters are constrained using an inverse approach based on the Neighborhood Algorithm. The model parameters include geometric characteristics as well as overthrusting rates, radiogenic heat production in the High Himalayan Crystalline (HHC) sequence, the age of initiation of the duplex or of out‐of‐sequence thrusting. Both models can provide a satisfactory fit to the inverted data. However, the model with out‐of‐sequence thrusting implies an unrealistic convergence rate ≥30 mm yr−1. The out‐of‐sequence thrust model can be adjusted to fit the convergence rate and the thermochronological data if the Main Central Thrust zone is assigned a constant geometry and a dip angle of about 30° and a slip rate of <1 mm yr−1. In the duplex model, the 20 mm yr−1 convergence rate is partitioned between an overthrusting rate of 5.8 ± 1.4 mm yr−1 and an underthrusting rate of 14.2 ± 1.8 mm yr−1. Modern rock uplift rates are estimated to increase from about 0.9 ± 0.31 mm yr−1 in the Lesser Himalaya to 3.0 ± 0.9 mm yr−1 at the front of the high range, 86 ± 13 km from the Main Frontal Thrust. The effective friction coefficient is estimated to be 0.07 or smaller, and the radiogenic heat production of HHC units is estimated to be 2.2 ± 0.1 μW m−3. The midcrustal duplex initiated at 9.8 ± 1.7 Ma, leading to an increase of uplift rate at front of the High Himalaya from 0.9 ± 0.31 to 3.05 ± 0.9 mm yr−1. We also run 3‐D models by coupling PECUBE with a landscape evolution model (CASCADE). This modeling shows that the effect of the evolving topography can explain a fraction of the scatter observed in the data but not all of it, suggesting that lateral variations of the kinematics of crustal deformation and exhumation are likely. It has been argued that the steep physiographic transition at the foot of the Greater Himalayan Sequence indicates OOS thrusting, but our results demonstrate that the best fit duplex model derived from the thermochronological and thermobarometric data reproduces the present morphology of the Nepal Himalaya equally well.
Tidal calibration of Plate Boundary Observatory borehole strainmeters: Roles of vertical and shear coupling
Authors: Roeloffs Evelyn
Published: June 2010

A multicomponent borehole strainmeter directly measures changes in the diameter of its cylindrical housing at several azimuths. To transform these measurements to formation strains requires a calibration matrix, which must be estimated by analyzing the installed strainmeter's response to known strains. Typically, theoretical calculations of Earth tidal strains serve as the known strains. This paper carries out such an analysis for 12 Plate Boundary Observatory (PBO) borehole strainmeters, postulating that each of the strainmeters' four gauges responds (“couples”) to all three horizontal components of the formation strain tensor, as well as to vertical strain. Orientation corrections are also estimated. The fourth extensometer in each PBO strainmeter provides redundant information used to reduce the chance that coupling coefficients could be misleadingly fit to inappropriate theoretical tides. Satisfactory fits between observed and theoretically calculated tides were obtained for three PBO strainmeters in California, where the calculated tides are corroborated by other instrumentation, as well as for six strainmeters in Oregon and Washington, where no other instruments have ever recorded Earth tidal strain. Several strainmeters have unexpectedly large coupling coefficients for vertical strain, which increases the strainmeter's response to atmospheric pressure. Vertical coupling diminishes, or even changes the sign of, the apparent response to areal strain caused by Earth tides or deep Earth processes because near the free surface, vertical strains are opposite in sign to areal strain. Vertical coupling does not impair the shear strain response, however. PBO borehole strainmeters can provide calibrated shear strain time series of transient strain associated with tectonic or magmatic processes.
Importance of water temperature and thermal stratification dynamics for temporal variation of surface water CO2 in a boreal lake
Authors: Åberg Jan , Jansson Mats , Jonsson Anders
Published: June 2010

Variation of the surface water CO2 concentration is likely to be the result of biological activity and physical processes such as water mixing and gas exchange with the atmosphere. Here we have studied the variations in surface water CO2 during the ice‐free period in the humic Lake Merasjärvi in northern Sweden. Meteorological, hydrological, and limnological data were collected using data logging equipment permitting high time resolution. The surface water of the lake was supersaturated with respect to CO2 throughout the study period. There were, however, considerable diurnal and longer‐term temporal variations of the surface water CO2 concentrations. Partial least squares models were used to link the logged CO2 data to the multivariate data set. On the longer‐term timescale (analyzed with 24 h means of the logged data), high concentrations of surface water CO2 were best related to the depth and temperature of the upper warmer layer (epilimnion), and to erosion of the underlying colder layer (hypolimnion). The diurnal variation (analyzed with 30 min means of the logged data) was best related to the thermal dynamics within the epilimnion, which regulated the surface water access to CO2 stores within this layer. Variables related to CO2 emission and photosynthesis (wind and photosynthetically active radiation) showed only weak correlations to variations of the surface water CO2 concentration. Accordingly, the CO2 flux, measured with the eddy‐covariance technique, was not correlated to the surface water CO2 concentration.
Vegetation‐infiltration relationships across climatic and soil type gradients
Authors: Thompson S. E. , Harman C. J. , Heine P. , Katul G. G.
Published: June 2010

The enhancement of infiltration capacity in the presence of vegetation is well documented in arid ecosystems where it can significantly impact the water balance and vegetation spatial organization. To begin progress toward developing a theory of vegetation‐infiltration interactions across a wide spectrum of climate regimes, three key questions are addressed: (1) Does vegetation also enhance infiltration capacity in mesic to hydric climates, and if so, what processes contribute to this enhancement? (2) Is there a canonical relationship between vegetation biomass and infiltration rate? and (3) How does the vegetation‐infiltration feedback evolve across climatic gradients? To address these three questions, new field data examining biomass‐infiltration relationships in different vegetation types in a humid climate and on loamy soils are combined with a meta‐analysis of biomass‐infiltration relationships from nearly 50 vegetation communities spanning a climatic gradient from hyperarid deserts to the humid tropics and representing a full spectrum of soil types. Infiltration capacity increased as a power law function of aboveground biomass in water‐limited ecosystems, but vegetation biomass was not significantly correlated to infiltration capacity in humid climates. Across a climatic gradient from xeric to hydric, the slope of the power law relationship between aboveground biomass and infiltration capacity decreased.
A neuroendocrine releasing effect of melatonin in the brain of an insect, Periplaneta americana (L.)
Authors: Richter Klaus , Peschke Elmar , Peschke Dorothee
Published: June 2010

Melatonin exists in nearly all organisms, but little is known of its function in non‐vertebrates. Long‐term perifusions as well as short‐term batch incubations of brains and molting glands of the cockroach Periplaneta americana were used to test the influence of melatonin
on the prothoracicotropic hormone, a glandotropic neuropeptide in the
brain, which stimulates the production of the molting hormone ecdysone in
the molting gland. Changes of ecdysteroid production in molting glands
were determined by radioimmunoassay as ecdysone equivalents. Melatonin
(10 nmol/L) was without effect on the prothoracic gland but stimulated
the prothoracicotropic effect of brains in both in vitro investigations, long‐term perifusions and short‐term batch incubations. The effect was dose‐dependent. The melatonin effect on the release of prothoracicotropic hormone in the brain was suppressed by luzindole (10 nmol/L), a pre‐synaptic receptor antagonist of melatonin. The retro‐cerebral complex (corpora cardiaca‐corpora allata) did not seem to be involved in the effect of melatonin on the brain. Serotonin (10 nmol/L) suppressed the release of prothoracicotropic hormone. This is the first experimental evidence of a neurohormonal releasing effect of melatonin in the insect nervous system.
Melatonin protects against the free radical‐induced impairment of nitric oxide production in the human umbilical artery
Authors: Wakatsuki Akihiko , Okatani Yuji
Published: June 2010

We evaluated melatonin's antioxidative effect on the free radical‐induced impairment of nitric oxide production in the human umbilical artery, which may play an important role in fetal hypoxia and ischemia during preeclampsia. Umbilical artery sections with intact endothelium were obtained from healthy pregnant women who were delivered between 37 and 40 wk of gestation. The production of nitric oxide in the umbilical arteries was stimulated by adding l‐arginine
followed by incubation for 60 min. Nitric oxide concentrations were
estimated by measuring nitrite ions (NO2−),
using high‐performance liquid chromatography. Prior to the addition of
l‐arginine, the segments were treated with hydrogen
peroxide (H2O2) alone (1, 10, 100 μM), or were
pretreated with either 50 mM mannitol or melatonin (20, 100, 500 μM)
before adding H2O2. Changes in
l‐arginine‐induced NO2−
production were expressed as a percentage of NO2− production at the end of preincubation.
NO2− production was significantly increased
by incubating the umbilical artery sections with
l‐arginine (P<0.01). Treatment with H2
O2 significantly reduced l‐arginine‐induced
NO2− production in a concentration‐dependent
manner (P<0.01). Pretreatment with melatonin significantly
increased NO2− production that had been
decreased by H2O2 in a concentration‐dependent
manner (P<0.01). Similarly, pretreatment with mannitol reversed
the H2O2‐induced reduction in NO2− production (P<0.001). These results indicate
that H2O2 may impair nitric oxide synthesis in the
endothelium of human umbilical arteries. Melatonin significantly
suppresses the H2O2‐induced inhibition effect of nitric oxide production, most likely through its ability to scavenge hydroxyl radicals.
Protective melatonin effect on oxidative stress induced by okadaic acid into rat brain
Authors: Túnez Isaac , Del Carmen Muñoz M. , Feijóo Montserrat , Muñoz‐Castañeda Juan R. , Bujalance Inmaculada , Valdelvira M. Elías , López Pedro Montilla
Published: June 2010

We studied the effect of melatonin on the oxidative changes produced by the intracerebroventricular (i.c.v.) injection of okadaic acid (200 ng/kg BW) in the Wistar rat. The effects of okadaic acid were evaluated as changes in the quantity of lipid peroxides, reduced glutathione content (GSH) and activity of antioxidative enzymes. Okadaic acid caused lipid peroxidation (5.35 ± 0.47 μmol/g tissue in the i.c.v. vehicle group versus 10.14 ± 0.88 μmol/g tissue in the okadaic acid group, P < 0.001), GSH consumption (0.115 ± 0.0065 μmol/g tissue in the i.c.v. vehicle group versus 0.024 ± 0.0021 μmol/g tissue, P < 0.001), and a reduction in the activity of GSH‐peroxidase, GSH‐reductase and GSH‐transferase between 60–80%. All these changes were prevented by pre‐injection of 4.5 mg melatonin per kg BW 2 hr before okadaic acid. These findings indicate: (i) okadaic acid induces a status of oxidative stress in the brain, characterized by a high level of lipid peroxidation, decreases in GSH content and diminished activities of antioxidative enzymes, and (ii) melatonin prevents the deleterious effects induced by okadaic acid. In conclusion, the results show the ability of melatonin to modify the neural response to okadaic acid with the protective mechanism likely involving the antioxidative processes of melatonin.
Non‐vertebrate melatonin
Authors: Hardeland Rüdiger , Poeggeler Burkhard
Published: June 2010

Abstract: Melatonin has been detected in bacteria, eukaryotic unicells, macroalgae, plants, fungi and various taxa of invertebrates. Although precise determinations are missing in many of these organisms and the roles of melatonin are still unknown, investigations in some species allow more detailed conclusions. Non‐vertebrate melatonin is not necessarily circadian, and if so, not always peaking at night, although nocturnal maxima are frequently found. In the cases under study, the major biosynthetic pathway is identical with that of vertebrates. Mimicking of photoperiodic responses and concentration changes upon temperature decreases have been studied in more detail only in dinoflagellates. In plants, an involvement in photoperiodism seems conceivable but requires further support. No stimulation of flowering has been demonstrated to date. A participation in antioxidative protection might be possible in many aerobic non‐vertebrates, although evidence for a contribution at physiological levels is mostly missing. Protection from stress by oxidotoxins or/and extensions of lifespan have been shown in very different organisms, such as the dinoflagellate Lingulodinium, the ciliate Paramecium, the rotifer Philodina and Drosophila. Melatonin can be taken up from the food, findings with possible implications in ecophysiology as well as for human nutrition and, with regard to high levels in medicinal plants, also in pharmacology.
Melatonin, xanthurenic acid, resveratrol, EGCG, vitamin C and α‐lipoic acid differentially reduce oxidative DNA damage induced by Fenton reagents: a study of their individual and synergistic actions
Authors: López‐Burillo Silvia , Tan Dun‐Xian , Mayo Juan C. , Sainz Rosa M. , Manchester Lucien C. , Reiter Russel J.
Published: June 2010

Abstract:  DNA damage generated by oxygen‐derived free radicals is related to mutagenesis, carcinogenesis and aging. In the last several years, hundreds of publications have confirmed that melatonin is a potent endogenous free radical scavenger. In the present in vitro study, we have examined the efficacy of three polyphenolic antioxidants, i.e. xanthurenic acid, resveratrol (3,4′,5‐trihydroxy‐trans‐stilbene) and (−)‐epigallocatechin‐3‐gallate (EGCG) and two classical non‐polyphenolic antioxidants, i.e. vitamin C (ascorbic acid) and α‐lipoic acid (LA, 1,2‐dithiolane‐3‐pentanoic acid) in inhibiting •OH‐induced oxidative DNA damage. We compared the efficacy of these five antioxidants with the effectiveness of melatonin (N‐acetyl‐5‐methoxytryptamine) and we also investigated the possible synergistic effects of melatonin with the other five molecules. Using high performance liquid chromatography (HPLC), the formation of 8‐hydroxy‐2‐deoxyguanosine (8‐OH‐dG) in purified calf thymus DNA treated with the Fenton reagents, chromium(III) (as CrCl3) plus hydrogen peroxide (H2O2) (Cr(III)/H2O2), was measured in the presence or absence of the antioxidants alone or in combination with melatonin. 8‐OH‐dG is considered a biomarker of oxidative DNA damage. Among the antioxidants tested, melatonin was the most effective of these with an IC50 = 3.6 ± 0.1 μm. For the other antioxidants the IC50 values were as follows: xanthurenic acid (IC50 = 7.9 ± 0.3), resveratrol (IC50 = 10.9 ± 0.3), EGCG (IC50 = 5.7 ± 0.3), vitamin C (IC50 = 16.9 ± 0.5) and LA (IC50 = 38.8 ± 0.7). These values differ from that of melatonin with a P < 0.01. Melatonin (1 μM) reversed the pro‐oxidant effect of resveratrol (0.5 μM) and vitamin C (0.5 μM), had an antagonistic effect when used in combination with EGCG (1 μM) and it exhibited synergism in combination with vitamin C (0.5 μM) and with LA (5 μM).
Melatonin prevents methotrexate‐induced hepatorenal oxidative injury in rats
Authors: Jahovic Nermina , Çevik Hülya , Şehirli A. Özer , Yeğen Berrak Ç. , Şener Göksel
Published: June 2010

Abstract: Regarding the mechanisms of methotrexate (MTX) hepatotoxicity and nephrotoxicity, several hypotheses have been put forward, among which oxidative stress (including depletion of glutathione) is likely. This investigation elucidates the role of free radicals in MTX‐induced toxicity and the protection by melatonin. Wistar albino rats were injected with MTX intraperitoneally. Following a single dose of MTX (20 mg/kg), either saline (MTX group) or melatonin (10 mg/kg, MTX + Mel group) was administered for 5 days. In other rats, physiologic saline (control group) or melatonin (10 mg/kg, Mel group) was injected for 5  days, following a single injection of saline. On the sixth day, rats were killed to obtain blood, liver, and kidney tissue samples. Malondialdehyde (MDA), an end product of lipid peroxidation, and glutathione (GSH), a key antioxidant, levels were evaluated in blood and tissue homogenates. Reactive oxygen metabolite‐induced inflammatory changes in kidney and liver tissues were evaluated by measuring myeloperoxidase (MPO) activity, an index of neutrophil infiltration. MTX administration resulted in increased MDA levels and MPO activity and decreased GSH levels in the blood, liver, and kidney whereas melatonin reversed these effects. When melatonin was administered alone, no significant changes in biochemical parameters were noted. In conclusion, the present study suggests that melatonin may be of therapeutic benefit when used with MTX.
Melatonin inhibits growth of diethylstilbestrol‐induced prolactin‐secreting pituitary tumor in vitro: possible involvement of nuclear RZR/ROR receptors
Authors: Karasek Michal , Gruszka Anna , Lawnicka Hanna , Kunert‐Radek Jolanta , Pawlikowski Marek
Published: June 2010

Melatonin exerts a marked antiproliferative action in numerous experimentally‐induced tumors in vivo as well as in both animal and human cell lines in vitro. However, the mechanisms of oncostatic action of melatonin is not clear, and the involvement of both membrane and nuclear receptors are suggested. Therefore, the aim of this study was to investigate effects of melatonin, and both agonist (CGP 52608), and antagonist (CGP 55644) of RZR/ROR nuclear receptors on the growth of diethylstilbestrol‐induced rat prolactin‐secreting pituitary tumor cells in vitro.

Pituitary tumors were induced by subcutaneous implantation of a single silastic capsule containing 10 mg of diethylstilbestrol in 4‐wk‐old male Fischer 344 rats. Four months after the implantation of capsules the animals were killed by decapitation, pituitary tumors were aseptically removed, mechanically dispersed, and enzymatically digested with 0.2% collagenase and 0.2% hyaluronidase. The cells (6 × 105 cells/well) were incubated for 24 hr in the presence of melatonin, CGP 52608, CGP 55644 and CGP 55644 plus melatonin (at the concentrations of 107 and 10−9 m) at 37°C in the humidified atmosphere of 95% air and 5% CO2. The group with the addition of solvent only served as control. The growth of cell was measured using the EZ4U system. Statistical analysis was performed using ANOVA followed by LSD test.

Both melatonin and CGP 52608 significantly suppressed growth of tumor cells in vitro in both used concentrations. CGP 55644 stimulated growth of tumor cells and blocked the inhibitory effects of melatonin in vitro.

Results of the present study as well as other experimental evidence strongly support the hypothesis that both membrane and nuclear receptors are involved in the oncostatic action of melatonin, and indicate that nuclear signalling plays an important role in this process.
Specific binding of melatonin to purified cell nuclei from mammary gland of swiss mice: day–night variations and effect of continuous light
Authors: Coto‐Montes Ana , Tomás‐Zapico Cristina , Escames Germaine , León Josefa , Rodríguez‐Colunga María Josefa , Tolivia Delio , Acuña‐Castroviejo Darío
Published: June 2010

Abstract: Melatonin binding sites were characterized in the nuclei of mouse mammary glands. The specific binding of 2‐125I‐iodomelatonin by homogenates of purified mammary gland cell nuclei was found to be rapid, reversible and saturable. Binding of 125I‐melatonin exhibited day–night variations with the highest binding affinity observed during the dark period and the lowest affinity at midday. However, when the animals were maintained under continuous light exposure, binding of 125I‐melatonin to cell nuclei showed a higher affinity than the daytime values found in animals maintained in normal photoperiod. Scatchard analysis of the binding data revealed the existence of a significant night–day variation in the binding kinetics, compatible with the existence of two classes of binding sites: a high‐affinity binding site expressed during the night, with KD = 185 ± 36 pm and a binding capacity of 6.24 ± 0.4 fmol/mg protein, and a low‐affinity site with KD = 562 ± 57 nm and Bmax = 7.56 ± 0.49 pmol/mg protein during the day. Interestingly, after 2 wk of continuous exposure to light, the animals killed at an equivalent midday time showed a significant increase in binding affinity, with KD = 1.43 ± 0.2 nm and Bmax = 24.75 ± 3.5 fmol/mg protein. Displacement experiments show an IC50 value compatible with the affinity constants obtained in the saturation experiments. These results indicate that the low‐affinity binding site may be saturated by the high levels of melatonin found in the mouse mammary gland, and sustain the hypothesis of a circadian regulation of these melatonin binding sites by the photoperiod.
Everything You Never Wanted to Know about Circular Analysis, but Were Afraid to Ask
Authors: Kriegeskorte Nikolaus , Lindquist Martin A , Nichols Thomas E , Poldrack Russell A , Vul Edward
Published: June 2010

Over the past year, a heated discussion about ‘circular’ or ‘nonindependent’ analysis in brain imaging has emerged in the literature. An analysis is circular (or nonindependent) if it is based on data that were selected for showing the effect of interest or a related effect. The authors of this paper are researchers who have contributed to the discussion and span a range of viewpoints. To clarify points of agreement and disagreement in the community, we collaboratively assembled a series of questions on circularity herein, to which we provide our individual current answers in ≤100 words per question. Although divergent views remain on some of the questions, there is also a substantial convergence of opinion, which we have summarized in a consensus box. The box provides the best current answers that the five authors could agree upon.
Impaired Dynamic Cerebral Autoregulation at Extreme High Altitude Even after Acclimatization
Authors: Iwasaki Ken-Ichi , Zhang Rong , Zuckerman Julie H , Ogawa Yojiro , Hansen Lærke H , Levine Benjamin David
Published: June 2010

Cerebral blood flow (CBF) increases and dynamic cerebral autoregulation is impaired by acute hypoxia. We hypothesized that progressive hypocapnia with restoration of arterial oxygen content after altitude acclimatization would normalize CBF and dynamic cerebral autoregulation. To test this hypothesis, dynamic cerebral autoregulation was examined by spectral and transfer function analyses between arterial pressure and CBF velocity variabilities in 11 healthy members of the Danish High-Altitude Research Expedition during normoxia and acute hypoxia (10.5% O2) at sea level, and after acclimatization (for over 1 month at 5,260 m at Chacaltaya, Bolivia). Arterial pressure and CBF velocity in the middle cerebral artery (transcranial Doppler), were recorded on a beat-by-beat basis. Steady-state CBF velocity increased during acute hypoxia, but normalized after acclimatization with partial restoration of SaO2 (acute, 78%±2%; chronic, 89%±1%) and progression of hypocapnia (end-tidal carbon dioxide: acute, 34±2 mm Hg; chronic, 21±1 mm Hg). Coherence (0.40±0.05 Units at normoxia) and transfer function gain (0.77±0.13 cm/s per mm Hg at normoxia) increased, and phase (0.86±0.15 radians at normoxia) decreased significantly in the very-low-frequency range during acute hypoxia (gain, 141%±24%; coherence, 136%±29%; phase, −25%±22%), which persisted after acclimatization (gain, 136%±36%; coherence, 131%±50%; phase, −42%±13%), together indicating impaired dynamic cerebral autoregulation in this frequency range. The similarity between both acute and chronic conditions suggests that dynamic cerebral autoregulation is impaired by hypoxia even after successful acclimatization to an extreme high altitude.
A modular gradient‐sensing network for chemotaxis in Escherichia coli revealed by responses to time‐varying stimuli
Authors: Shimizu Thomas S , Tu Yuhai , Berg Howard C
Published: June 2010

The Escherichia coli chemotaxis‐signaling pathway computes time derivatives of chemoeffector concentrations. This network features modules for signal reception/amplification and robust adaptation, with sensing of chemoeffector gradients determined by the way in which these modules are coupled in vivo. We characterized these modules and their coupling by using fluorescence resonance energy transfer to measure intracellular responses to time‐varying stimuli. Receptor sensitivity was characterized by step stimuli, the gradient sensitivity by exponential ramp stimuli, and the frequency response by exponential sine‐wave stimuli. Analysis of these data revealed the structure of the feedback transfer function linking the amplification and adaptation modules. Feedback near steady state was found to be weak, consistent with strong fluctuations and slow recovery from small perturbations. Gradient sensitivity and frequency response both depended strongly on temperature. We found that time derivatives can be computed by the chemotaxis system for input frequencies below 0.006 Hz at 22°C and below 0.018 Hz at 32°C. Our results show how dynamic input–output measurements, time honored in physiology, can serve as powerful tools in deciphering cell‐signaling mechanisms.