bluuebunny/crossref_metadata_2025 huggingface dataset:
FELINE ATRIAL NATRIURETIC PEPTIDE (ANP) HAS A SINGLE COPY GENE
Authors: BIONDO A.W. , STEENBERGEN S. , SISSON D. , SOLTER P.
Published: December 2014

O peptídeo natriurético atrial felino (PNA) é um hormônio sintetizado pelo miocárdio cardíaco atrial que, uma vez liberado na circulação, produz diurese, natriurese e vasodilatação periférica. Nós recentemente isolamos, sequenciamos e estabelemos a expressão cardíaca normal do PNA felino. No presente estudo, nós apresentamos o número de cópias gênicas do PNA em gatos. Foram extraídas amostras de DNA genômico do sangue periférico humano e felino, as quais foram purificadas e digeridas com as enzimas de restrição EcoRI, BamHI e HindIII, com posterior realização da técnica de Southern Blots. Primers para PCR, confeccionados para regiões de alta conservatividade entre espécies, foram utilizados para amplificação, clonagem e sequenciamento de um produto de 900 pares de bases, posteriormente utilizado como sonda de DNA. O gene do PNA felino possui uma única cópia gênica, a exemplo do PNA humano. Devido a sua similaridade, sondas de DNA felino puderam ser utilizadas para a hibridização de DNA genômico tanto do gato como do homem. Abstract Atrial natriuretic peptide (ANP) is a hormone normally synthesized by the cardiac atrial myocardium that once released, produces diuresis, natriuresis and peripheral vasodilation. We have recently isolated, sequenced and assessed the normal cardiac expression of feline ANP. In this study, we report on the number of copies of the feline ANP gene, which could have an effect on future molecular biology studies of ANP gene expression in cat models of cardiovascular disease. Cat and human genomic DNA (gDNA) were extracted for Southern blotting from blood. The purified DNA was digested with the restriction enzymes EcoRI, BamHI and HindIII followed by agarose gel electrophoresis and blotting onto nytran membranes. A feline ANP cDNA probe of approximately 900 base pairs was used for hybridization of the membranes. The results of Southern blotting showed that both the feline and human genomes contain a single copy of the ANP gene.
Intrastriatal Transplantation of Adult Human Neural Crest-Derived Stem Cells Improves Functional Outcome in Parkinsonian Rats
Authors: Müller Janine , Ossig Christiana , Greiner Johannes F.W. , Hauser Stefan , Fauser Mareike , Widera Darius , Kaltschmidt Christian , Storch Alexander , Kaltschmidt Barbara
Published: December 2014

Parkinson's disease (PD) is considered the second most frequent and one of the most severe neurodegenerative diseases, with dysfunctions of the motor system and with nonmotor symptoms such as depression and dementia. Compensation for the progressive loss of dopaminergic (DA) neurons during PD using current pharmacological treatment strategies is limited and remains challenging. Pluripotent stem cell-based regenerative medicine may offer a promising therapeutic alternative, although the medical application of human embryonic tissue and pluripotent stem cells is still a matter of ethical and practical debate. Addressing these challenges, the present study investigated the potential of adult human neural crest-derived stem cells derived from the inferior turbinate (ITSCs) transplanted into a parkinsonian rat model. Emphasizing their capability to give rise to nervous tissue, ITSCs isolated from the adult human nose efficiently differentiated into functional mature neurons in vitro. Additional successful dopaminergic differentiation of ITSCs was subsequently followed by their transplantation into a unilaterally lesioned 6-hydroxydopamine rat PD model. Transplantation of predifferentiated or undifferentiated ITSCs led to robust restoration of rotational behavior, accompanied by significant recovery of DA neurons within the substantia nigra. ITSCs were further shown to migrate extensively in loose streams primarily toward the posterior direction as far as to the midbrain region, at which point they were able to differentiate into DA neurons within the locus ceruleus. We demonstrate, for the first time, that adult human ITSCs are capable of functionally recovering a PD rat model.
Increasing the use of second‐line therapy is a cost‐effective approach to prevent the spread of drug‐resistant HIV: a mathematical modelling study
Authors: Nichols Brooke E , Sigaloff Kim CE , Kityo Cissy , Hamers Raph L , Baltussen Rob , Bertagnolio Silvia , Jordan Michael R , Hallett Timothy B , Boucher Charles AB , de Wit Tobias F Rinke , van de Vijver David AMC
Published: December 2014

Introduction

Earlier antiretroviral therapy (ART) initiation reduces HIV‐1 incidence. This benefit may be offset by increased transmitted drug resistance (TDR), which could limit future HIV treatment options. We analyze the epidemiological impact and cost‐effectiveness of strategies to reduce TDR.

Methods

We develop a deterministic mathematical model representing Kampala, Uganda, to predict the prevalence of TDR over a 10‐year period. We then compare the impact on TDR and cost‐effectiveness of: (1) introduction of pre‐therapy genotyping; (2) doubling use of second‐line treatment to 80% (50–90%) of patients with confirmed virological failure on first‐line ART; and (3) increasing viral load monitoring from yearly to twice yearly. An intervention can be considered cost‐effective if it costs less than three times the gross domestic product per capita per quality adjusted life year (QALY) gained, or less than $3420 in Uganda.

Results

The prevalence of TDR is predicted to rise from 6.7% (interquartile range [IQR] 6.2–7.2%) in 2014, to 6.8% (IQR 6.1–7.6%), 10.0% (IQR 8.9–11.5%) and 11.1% (IQR 9.7–13.0%) in 2024 if treatment is initiated at a CD4 <350, <500, or immediately, respectively. The absolute number of TDR cases is predicted to decrease 4.4–8.1% when treating earlier compared to treating at CD4 <350 due to the preventative effects of earlier treatment. Most cases of TDR can be averted by increasing second‐line treatment (additional 7.1–10.2% reduction), followed by increased viral load monitoring (<2.7%) and pre‐therapy genotyping (<1.0%). Only increasing second‐line treatment is cost‐effective, ranging from $1612 to $2234 (IQR $450‐dominated) per QALY gained.

Conclusions

While earlier treatment initiation will result in a predicted increase in the proportion of patients infected with drug‐resistant HIV, the absolute numbers of patients infected with drug‐resistant HIV is predicted to decrease. Increasing use of second‐line treatment to all patients with confirmed failure on first‐line therapy is a cost‐effective approach to reduce TDR. Improving access to second‐line ART is therefore a major priority.
Genome-wide mapping in a house mouse hybrid zone reveals hybrid sterility loci and Dobzhansky-Muller interactions
Authors: Turner Leslie M , Harr Bettina
Published: December 2014

Mapping hybrid defects in contact zones between incipient species can identify genomic regions contributing to reproductive isolation and reveal genetic mechanisms of speciation. The house mouse features a rare combination of sophisticated genetic tools and natural hybrid zones between subspecies. Male hybrids often show reduced fertility, a common reproductive barrier between incipient species. Laboratory crosses have identified sterility loci, but each encompasses hundreds of genes. We map genetic determinants of testis weight and testis gene expression using offspring of mice captured in a hybrid zone between M. musculus musculus and M. m. domesticus. Many generations of admixture enables high-resolution mapping of loci contributing to these sterility-related phenotypes. We identify complex interactions among sterility loci, suggesting multiple, non-independent genetic incompatibilities contribute to barriers to gene flow in the hybrid zone.
Postseismic response of repeating earthquakes around the 2011 Tohoku‐oki earthquake: Moment increases due to the fast loading rate
Authors: Uchida Naoki , Shimamura Kouhei , Matsuzawa Toru , Okada Tomomi
Published: December 2014

We examined the temporal variation of the size of repeating earthquakes related to the 2011 Tohoku‐oki earthquake (M9.0) in the northeastern Japan subduction zone for the period from July 1984 to the end of 2011. The repeaters (M2.5–6.1) show postseismic magnitude increases for most sequences located in the area of large postseismic slip at the downdip extension of the M9 source region. The magnitudes of the first events after the M9 earthquake increased by an average of about 0.3 for sequences having three or more earthquakes over the 9 months following it. We also examined the slip area in detail for Kamaishi repeaters whose magnitudes had been M4.9 ± 0.2 but which increased by about 1 after the M9 earthquake. Waveform modeling shows that the slip area for the post‐M9 Kamaishi earthquakes overlaps with that before the Tohoku‐oki earthquake but enlarged by about 6 times. Until the occurrence time of the last event (September 2011) in the analysis period, the rupture area remained larger than before but appeared to shrink over time. The enlargement of the rupture area suggests that an aseismic‐to‐seismic transition occurred in the region surrounding the pre‐M9 repeaters and is most likely related to fast loading of the repeaters due to rapid postseismic slip estimated to have occurred in the area. The existence of conditionally stable regions around the repeating earthquakes and/or patches slightly larger than the earthquake nucleation sizes may explain such behavior. The temporal change of loading rate is an important factor in determining earthquake size in this case.
Theodore Richard Madden (1925–2013)
Authors: Williams Earle , Madden Nadia , Madden Jennifer , Madden Halima
Published: December 2014

Theodore R. Madden, lifelong professor of geophysics at the Massachusetts Institute of Technology (MIT), fascinated with all things electromagnetic, ingenious in bridging theory with experiment, AGU Fellow, and a geophysicist's geophysicist, died on 11 November 2013 at age 88. A special symposium and memorial (http://eapsweb.mit.edu/news/2014/madden‐memorial) was held at MIT on 14 March 2014 on the occasion of his birthday. At that time, Frank Press, former president of the U.S. National Academy of Sciences, said, “Ted Madden and his students put geophysics on the map at MIT.”
Ocean carbon uptake more variable than previously thought
Authors: Betz Eric O.
Published: December 2014

Earth's oceans are thought to have taken up about one quarter of the carbon dioxide (CO2) that humans pumped into the atmosphere in the past 2 decades. The CO2 drives acidification and has consequences for sea life, but it also moderates the rate of climate change.
River slope connects modern topography with ancient tectonics
Authors: Wendel JoAnna
Published: December 2014

Scientists believe that topographic features are shaped by the tectonic history of the surrounding environment. However, although models exist that relate a known tectonic history to the expected shape of the rivers, the opposite problem of finding the tectonic history that resulted in an observed river‐dominated landscape remains challenging. Past researchers have used smoothing of topographic data to find averages of tectonic information or have attempted many different tectonic histories and compared their expected output against the real topography. Now, Goren et al. have expanded on these methods with two new models.
A noninvasive way to study groundwater‐dependent ecosystems
Authors: Orwig Jessica
Published: December 2014

Some entire ecosystems need groundwater to survive. These are called groundwater‐dependent ecosystems (GDE). These ecosystems are particularly sensitive to environmental change, but GDEs are poorly understood, and the complex underground architecture is especially difficult to study without invasive tools that could disrupt the delicate environment. Chambers et al. introduce a new way to study these environments.
Uncertainty in deforestation's effects on Amazonian climate
Authors: Schultz Colin
Published: December 2014

Deforestation of the Amazon rainforest is expected to cause the temperature in the region to rise and rainfall patterns to shift. Exactly how and how much the regional climate will change in the face of rampant deforestation, however, is a matter of considerable ongoing investigation. With their research, Lorenz and Pitman add a new piece to the puzzle by showing that the strength of land‐atmosphere coupling in a given model influences how it represents deforestation's effects.
Where does the bed of a river change from gravel to sand?
Authors: Wendel JoAnna
Published: December 2014

Along a riverbed, sediment grains often shrink from gravel sized to sand sized farther downstream. Scientists have documented this phenomenon well, although they are still puzzled by certain details of the gravel‐to‐sand transition, including why exactly the transition occurs and why it occurs more abruptly in some rivers and more gradually in others.
Toward a unified hydrous olivine electrical conductivity law
Authors: Gardés Emmanuel , Gaillard Fabrice , Tarits Pascal
Published: December 2014

It has long been proposed that water incorporation in olivine has dramatic effects on the upper mantle properties, affecting large‐scale geodynamics, and triggering high electrical conductivity. But the laboratory‐based laws of olivine electrical conductivity predict contrasting effects of water, precluding the interpretation of geophysical data in term of mantle hydration. We review the experimental measurements of hydrous olivine conductivity and conclude that most of data are consistent when errors in samples water contents are considered. We report a new law calibrated on the largest database of measurements on hydrous olivine oriented single crystals and polycrystals. It fits most of measurements within uncertainties, and is compatible with most of geophysical data within petrological constraints on mantle olivine hydration. The conductivity anisotropy of hydrous olivine might be higher than dry olivine, but preferential orientation should produce moderate anisotropy (∼0–0.8 log unit). In the oceanic mantle, the enhancement of olivine conductivity is limited to ∼1 log unit in the maximum range of mantle olivine water concentrations (0–500 wt ppm). Strongest enhancements are expected in colder regions, like cratonic lithospheres and subduction settings. High conductivities in melt‐free mantle require great depths and high water concentrations in olivine (>0.1 S/m at >250 km and >200 wt ppm). Thus, the hydration of olivine appears unlikely to produce the highest conductivities of the upper mantle.
Arctic greening can cause earlier seasonality of Arctic amplification
Authors: Chae Yoojeong , Kang Sarah M. , Jeong Su‐Jong , Kim Baekmin , Frierson Dargan M. W.
Published: December 2014

As global temperatures rise, vegetation types will change, particularly in the northern high latitudes. Under a warming scenario, shrub and grasslands over the Arctic are expected to shift to boreal forests. This study compares the impact of such a change in Arctic vegetation type with that of CO2 doubling on the seasonality of Arctic warming. Even though vegetation is changed throughout the year, the effect of the surface albedo change is maximum in boreal summer when the incoming solar radiation is largest. Evapotranspiration changes are also maximized in the summer, when the photosynthesis rate is highest. As a result, when Arctic vegetation change is considered in addition to doubled CO2, Arctic amplification is maximized earlier in the annual cycle.
Stress‐based aftershock forecasts made within 24 h postmain shock: Expected north San Francisco Bay area seismicity changes after the 2014M = 6.0 West Napa earthquake
Authors: Parsons Tom , Segou Margaret , Sevilgen Volkan , Milner Kevin , Field Edward , Toda Shinji , Stein Ross S.
Published: December 2014

We calculate stress changes resulting from theM = 6.0 West Napa earthquake on north San Francisco Bay area faults. The earthquake ruptured within a series of long faults that pose significant hazard to the Bay area, and we are thus concerned with potential increases in the probability of a large earthquake through stress transfer. We conduct this exercise as a prospective test because the skill of stress‐based aftershock forecasting methodology is inconclusive. We apply three methods: (1) generalized mapping of regional Coulomb stress change, (2) stress changes resolved on Uniform California Earthquake Rupture Forecast faults, and (3) a mapped rate/state aftershock forecast. All calculations were completed within 24 h after the main shock and were made without benefit of known aftershocks, which will be used to evaluative the prospective forecast. All methods suggest that we should expect heightened seismicity on parts of the southern Rodgers Creek, northern Hayward, and Green Valley faults.
The chain response of the magnetospheric and ground magnetic field to interplanetary shocks
Authors: Sun T. R. , Wang C. , Zhang J. J. , Pilipenko V. A. , Wang Y. , Wang J. Y.
Published: December 2014

In response to interplanetary (IP) shocks, magnetic field may decrease/increase (negative/positive response) in nightside magnetosphere, while at high latitudes on the ground it has two‐phase bipolar variations: preliminary impulse and main impulse (MI). Using global MHD simulations, we investigate the linkage between the MI phase variation on the ground and the magnetospheric negative response to an IP shock. It is revealed that although the two phenomena occur at largely separated locations, they are physically related and form a response chain. The velocity disturbances near the flanks of the magnetopause cause the magnetic field to decrease, resulting in a dynamo which thus powers the transient field‐aligned currents (FACs). These FACs further generate a pair of ionospheric current vortex, leading to MI variations on the ground. Therefore, we report here the intrinsic physically related chain response of the magnetospheric and ground magnetic field to IP shocks, and thus link the magnetospheric sudden impulse (SI) and ground SI together.
In situ observations of velocity changes in response to tidal deformation from analysis of the high‐frequency ambient wavefield
Authors: Hillers G. , Retailleau L. , Campillo M. , Inbal A. , Ampuero J.‐P. , Nishimura T.
Published: December 2014

We report systematic seismic velocity variations in response to tidal deformation. Measurements are made on correlation functions of the ambient seismic wavefield at 2–8 Hz recorded by a dense array at the site of the Piñon Flat Observatory, Southern California. The key observation is the dependence of the response on the component of wave motion and coda lapse time τ. Measurements on the vertical correlation component indicate reduced wave speeds during periods of volumetric compression, whereas data from horizontal components show the opposite behavior, compatible with previous observations. These effects are amplified by the directional sensitivities of the different surface wave types constituting the early coda of vertical and horizontal correlation components to the anisotropic behavior of the compliant layer. The decrease of the velocity (volumetric) strain sensitivity Sθ with τ indicates that this response is constrained to shallow depths. The observed velocity dependence on strain implies nonlinear behavior, but conclusions regarding elasticity are more ambiguous. The anisotropic response is possibly associated with inelastic dilatancy of the unconsolidated, low‐velocity material above the granitic basement. However, equal polarity of vertical component velocity changes and deformation in the vertical direction indicate that a nonlinear Poisson effect is similarly compatible with the observed response pattern. Peak relative velocity changes at small τ are 0.03%, which translates into an absolute velocity strain sensitivity of Sθ≈5 × 103 and a stress sensitivity of 0.5 MPa−1. The potentially evolving velocity strain sensitivity of crustal and fault zone materials can be studied with the method introduced here.
GPS as an independent measurement to estimate terrestrial water storage variations in Washington and Oregon
Authors: Fu Yuning , Argus Donald F. , Landerer Felix W.
Published: December 2014

The Global Positioning System (GPS) measures elastic ground loading deformation in response to hydrological mass variations on or near Earth's surface. We present a time series of change in terrestrial water storage as a function of position in Washington and Oregon estimated using GPS measurements of vertical displacement of Earth's surface. The distribution of water variation inferred from GPS is highly correlated with physiographic provinces: the seasonal water is mostly located in the mountain areas, such as the Cascade Range and Olympic Mountains, and is much smaller in the basin and valley areas of the Columbia Basin and Harney Basin. GPS is proven to be an independent measurement to distinguish between hydrological models. The drought period of 2008–2010 (maximum in 2010) and the recovery period of 2011–2012 in the Cascade Range are well recovered with GPS‐determined time‐variable monthly water mass series. The GPS‐inferred water storage variation in the Cascade Range is consistent with that derived from JPL's GRACE monthly mass grid solutions. The percentage of RMS reduction is ~62% when we subtract GRACE water series from GPS‐derived results. GPS‐determined water storage variations can fill gaps in the current GRACE mission, also in the transition period from the current GRACE to the future GRACE Follow‐on missions. We demonstrate that the GPS‐inferred water storage variations can determine and verify local scaling factors for GRACE measurements; in the Cascade Range, the RMS reduction between GRACE series scaled by GPS and scaled by the hydrological model‐based GRACE Tellus gain factors is up to 90.5%.
Forced and intrinsic variability in the response to increased wind stress of an idealized Southern Ocean
Authors: Wilson Chris , Hughes Chris W. , Blundell Jeffrey R.
Published: December 2014

We use ensemble runs of a three layer, quasi‐geostrophic idealized Southern Ocean model to explore the roles of forced and intrinsic variability in response to a linear increase of wind stress imposed over a 30 year period. We find no increase of eastward circumpolar volume transport in response to the increased wind stress. A large part of the resulting time series can be explained by a response in which the eddy kinetic energy is linearly proportional to the wind stress with a possible time lag, but no statistically significant lag is found. However, this simple relationship is not the whole story: several intrinsic time scales also influence the response. We find an e‐folding time scale for growth of small perturbations of 1–2 weeks. The energy budget for intrinsic variability at periods shorter than a year is dominated by exchange between kinetic and potential energy. At longer time scales, we find an intrinsic mode with period in the region of 15 years, which is dominated by changes in potential energy and frictional dissipation in a manner consistent with that seen by Hogg and Blundell (2006). A similar mode influences the response to changing wind stress. This influence, robust to perturbations, is different from the supposed linear relationship between wind stress and eddy kinetic energy, and persists for 5–10 years in this model, suggestive of a forced oscillatory mode with period of around 15 years. If present in the real ocean, such a mode would imply a degree of predictability of Southern Ocean dynamics on multiyear time scales.
Impacts of urbanization on Indian summer monsoon rainfall extremes
Authors: Shastri Hiteshri , Paul Supantha , Ghosh Subimal , Karmakar Subhankar
Published: December 2014

Urban areas have different climatology with respect to their rural surroundings. Though urbanization is a worldwide phenomenon, it is especially prevalent in India, where urban areas have experienced an unprecedented rate of growth over the last 30 years. Here we take up an observational study to understand the influence of urbanization on the characteristics of precipitation (specifically extremes) in India. We identify 42 urban regions and compare their extreme rainfall characteristics with those of surrounding rural areas. We observe that, on an overall scale, the urban signatures on extreme rainfall are not prominently and consistently visible, but they are spatially nonuniform. Zonal analysis reveals significant impacts of urbanization on extreme rainfall in central and western regions of India. An additional examination, to understand the influences of urbanization on heavy rainfall climatology, is carried with station level data using a statistical method, quantile regression. This is performed for the most populated city of India, Mumbai, in pair with a nearby nonurban area, Alibaug; both having similar geographic location. The derived extreme rainfall regression quantiles reveal the sensitivity of extreme rainfall events to the increased urbanization. Overall the study identifies the climatological zones in India, where increased urbanization affects regional rainfall pattern and extremes, with a detailed case study of Mumbai. This also calls attention to the need of further experimental investigation, for the identification of the key climatological processes, in different regions of India, affected by increased urbanization.
Quantifying the heat flux regulation of metropolitan land use/land cover components by coupling remote sensing modeling with in situ measurement
Authors: Kuang Wenhui , Dou Yinyin , Zhang Chi , Chi Wenfeng , Liu Ailin , Liu Yue , Zhang Renhua , Liu Jiyuan
Published: December 2014

Quantifying the effects of urban land use/land cover with regard to surface radiation and heat flux regulation is important to ecological planning and heat stress mitigation. To retrieve the spatial pattern of heat fluxes in the Beijing metropolitan area, China, a remote sensing‐based energy balance model was calibrated with synchronously measured energy fluxes including net radiation, latent heat flux (LE), and sensible heat flux (H). Our model calibration approach avoided the uncertainties due to subjective judgments in previous empirical parameterization methods. The land surface temperature (LST), H, and Bowen ratio (β) of Beijing were found to increase along the outskirt‐suburban‐urban gradient, with strong spatial variation. LST and H were negatively correlated with vegetation fraction cover (VFC). For example, the modern high‐rise residential areas with relatively higher VFC had lower H and β than the traditional low‐rise residential areas. Our findings that indicate thermal dissipation through vegetation transpiration might play an important role in urban heat regulation. Notably, the thermal dissipating strength of vegetation (calculated as LE/VFC) declined exponentially with increased VFC. For the purpose of heat stress regulation, we recommend upgrading the traditional low‐rise residential areas to modern high‐rise residential areas and focusing urban greenery projects in areas whose VFC < 0.1, where the heat regulating service by urban vegetation could be twice as effective as in other places.
Projecting policy‐relevant metrics for high summertime ozone pollution events over the eastern United States due to climate and emission changes during the 21st century
Authors: Rieder Harald E. , Fiore Arlene M. , Horowitz Larry W. , Naik Vaishali
Published: December 2014

Over the eastern United States (EUS), nitrogen oxides (NOx) emission controls have led to improved air quality over the past two decades, but concerns have been raised that climate warming may offset some of these gains. Here we analyze the effect of changing emissions and climate, in isolation and combination, on EUS summertime surface ozone (O3) over the recent past and the 21st century in an ensemble of simulations performed with the Geophysical Fluid Dynamics Laboratory CM3 chemistry‐climate model. The simulated summertime EUS O3 is biased high but captures the structure of observed changes in regional O3 distributions following NOx emission reductions. We introduce a statistical bias correction, which allows derivation of policy‐relevant statistics by assuming a stationary mean state bias in the model, but accurate simulation of changes at each quantile of the distribution. We contrast two different 21st century scenarios: (i) representative concentration pathway (RCP) 4.5 and (ii) simulations with well‐mixed greenhouse gases (WMGG) following RCP4.5 but with emissions of air pollutants and precursors held fixed at 2005 levels (RCP4.5_WMGG). We find under RCP4.5 no exceedance of maximum daily 8 hour average ozone above 75 ppb by mid‐21st century, reflecting the U.S. NOx emissions reductions projected in RCP4.5, while more than half of the EUS exceeds this level by the end of the 21st century under RCP4.5_WMGG. Further, we find a simple relationship between the changes in estimated 1 year return levels and regional NOx emission changes, implying that our results can be generalized to estimate changes in the frequency of EUS pollution events under different regional NOx emission scenarios.
Quantitative attribution of major driving forces on soil organic carbon dynamics
Authors: Wu Yiping , Liu Shuguang , Tan Zhengxi
Published: December 2014

Soil organic carbon (SOC) storage plays a major role in the global carbon cycle and is affected by many factors including land use/management changes (e.g., biofuel production‐oriented changes). However, the contributions of various factors to SOC changes are not well understood and quantified. This study was designed to investigate the impacts of changing farming practices, initial SOC levels, and biological enhancement of grain production on SOC dynamics and to attribute the relative contributions of major driving forces (CO2 enrichment and farming practices) using a fractional factorial modeling design. The case study at a crop site in Iowa in the United States demonstrated that the traditional corn‐soybean (CS) rotation could still accumulate SOC over this century (from 4.2 to 6.8 kg C/m2) under the current condition; whereas the continuous‐corn (CC) system might have a higher SOC sequestration potential than CS. In either case, however, residue removal could reduce the sink potential substantially. Long‐term simulation results also suggested that the equilibrium SOC level may vary greatly (∼5.7 to ∼11 kg C/m2) depending on cropping systems and management practices, and projected growth enhancement could make the magnitudes higher (∼7.8 to ∼13 kg C/m2). Importantly, the factorial design analysis indicated that residue management had the most significant impact (contributing 49.4%) on SOC changes, followed by CO2 Enrichment (37%), Tillage (6.2%), the combination of CO2 Enrichment‐Residue removal (5.8%), and Fertilization (1.6%). In brief, this study is valuable for understanding the major forces driving SOC dynamics of agroecosystems and informative for decision‐makers when seeking the enhancement of SOC sequestration potential and sustainability of biofuel production, especially in the Corn Belt region of the United States.
Forecasting Space Weather Events for a Neighboring World
Authors: Zheng Yihua , Mason Tom , Wood Erin L.
Published: December 2014

Key Points

The Martian atmosphere's response to a front of SEPs

Enlil is running in real time at CCMC
They made you perfect: A test of the Social Reaction Model of Perfectionism
Authors: Wilson Claire , Hunter Simon C. , Rasmussen Susan , McGowan Allison
Published: December 2014

Perfectionism serves as a mediator in the relationship between difficult life experiences and psychological distress, but to date no research has examined the effect of recalled peer victimization on perfectionism and adult depressive symptomatology (DS). The present study assessed the Social Reaction Model of Perfectionism (SRMP; Flett, Hewitt, Oliver, & Macdonald (2002b). Perfectionism in children and their parents: A developmental analysis. In G. L. Flett and P. L. Hewitt (Eds.), Perfectionism: Theory, research, and treatment (pp. 89–132). Washington: American Psychological Association), which proposes that perfectionism (self‐oriented, other‐oriented and socially prescribed perfectionism) results from harsh experiences. This may include experiences of peer victimization (physical, verbal and indirect). The model was extended to also include adult DS and rumination (brooding and reflection). Self‐report questionnaires measuring recalled childhood experiences of peer victimization (Owens, Daly, & Slee (2005). Aggressive Behavior, 31, 1–12. doi: 10.1002/ab.20045), current trait perfectionism (Hewitt & Flett (1991). Journal of Personality and Social Psychology, 60, 456–470. http://dx.doi.org/10.1037//0022‐3514.60.3.456), rumination (Nolen‐Hoeksema & Morrow (1991). Journal of Personality and Social Psychology, 61, 115–121. doi: 10.1037/0022‐3514.61.1.115) and DS (Radloff (1977). Applied Psychological Measurement, 1, 386–401. http://dx.doi.org/10.1177/014662167700100306) were completed by 338 adult participants (54% female). Path‐analyses revealed recalled indirect victimization to be associated with adults' self‐oriented and socially prescribed perfectionism. However, only socially prescribed perfectionism mediated the relation between recalled indirect victimization and adult DS. Brooding rumination also mediated the effect of socially prescribed perfectionism upon DS. The findings support the SRMP, and extend the theory to include the effects of perfectionism on rumination and DS. Aggr. Behav. 41:421–431, 2015. © 2014 Wiley Periodicals, Inc.
and filter design for polytopic continuous‐time Markov jump linear systems with uncertain transition rates
Authors: Morais Cecília F. , Braga Márcio F. , Lacerda Márcio J. , Oliveira Ricardo C. L. F. , Peres Pedro L. D.
Published: December 2014

This paper addresses the problems of
and
full‐order filter design for continuous‐time Markov jump linear systems subject to uncertainties. Different from the available methods in the literature, the main novelty of the proposed approach is the possibility of computing bounds to the
and
norms of the augmented system composed by the uncertain Markov jump linear system plus the robust filter through Lyapunov matrices depending polynomially on the uncertainties affecting independently the matrices of each operation mode and the transition rate matrix. By means of a suitable representation of the uncertainties, the proposed filter design conditions are expressed in terms of linear matrix inequality relaxations associated with searches on scalar parameters. As an additional flexibility, the conditions can be used to synthesize filters with partial, complete, or null Markov mode availability. Numerical experiments illustrate that the proposed approach is more general and can be less conservative than the available methods. Copyright © 2014 John Wiley & Sons, Ltd.
Development of Functional Poly(amido amine) CXCR4 Antagonists with the Ability to Mobilize Leukocytes and Deliver Nucleic Acids
Authors: Wang Yan , Hazeldine Stuart T. , Li Jing , Oupický David
Published: December 2014

CXCR4 chemokine receptor plays a crucial role in metastatic spread of multiple types of cancer. The present study reports on synthesis of functional polymers based on newly synthesized CXCR4‐inhibiting monomers. The resultant linear polymeric CXCR4 antagonists (PCX) show improved ability to inhibit CXCR4 when compared with the monomers. The CXCR4 antagonism provides PCX with the ability to mobilize leukocytes from bone marrow to peripheral blood and to inhibit cancer cell invasion. Due to their cationic nature, PCX can form polyplexes with DNA and mediate efficient transfection. The reported findings validate PCX as promising dual‐function polymeric drugs that can deliver therapeutic nucleic acids and improve cancer therapy by simultaneously inhibiting CXCR4 chemokine receptor.
Hydrogen‐Bonded Multilayers of Tannic Acid as Mediators of T‐Cell Immunity
Authors: Kozlovskaya Veronika , Xue Bing , Lei Weiqi , Padgett Lindsey E. , Tse Hubert M. , Kharlampieva Eugenia
Published: December 2014

Type 1 diabetes is an autoimmune‐mediated disease resulting in the destruction of insulin‐secreting pancreatic β‐cells. Transplantation of insulin‐producing islets is a viable treatment to restore euglycemia in Type 1 diabetics; however, the clinical application remains limited due to the use of toxic immunosuppressive therapies to prevent immune‐mediated rejection. A nanothin polymer material with dual antioxidant and immunosuppressive properties capable of modulating both innate and adaptive immune responses crucial for transplantation outcome is presented. Through the use of hollow microparticles (capsules) composed of hydrogen‐bonded multilayers of natural polyphenol (tannic acid) with poly(N‐vinylpyrrolidone) (TA/PVPON) and with poly(N‐vinylcaprolactam) (TA/PVCL), proinflammatory reactive oxygen and nitrogen species are efficiently dissipated and the production of interferon (IFN)‐γ and tumor necrosis factor (TNF)‐α proinflammatory cytokines is attenuated by cognate antigen‐stimulated autoreactive CD4+ T cells. These results provide evidence that TA‐containing capsules are efficacious in immunomodulation and may provide physical transplant protection and prevent diabetogenic autoreactive T‐cell responses. Future studies will determine if xeno‐ and allotransplantation with (TA/PVPON)‐ or (TA/PVCL)‐coated pancreatic islets will decrease the risk of graft rejection due to attenuation of oxidative stress and IFN‐γ, and restore euglycemia in Type 1 diabetics.
Chemically Specific Multiscale Modeling of Clay–Polymer Nanocomposites Reveals Intercalation Dynamics, Tactoid Self‐Assembly and Emergent Materials Properties
Authors: Suter James L. , Groen Derek , Coveney Peter V.
Published: December 2014

A quantitative description is presented of the dynamical process of polymer intercalation into clay tactoids and the ensuing aggregation of polymer‐entangled tactoids into larger structures, obtaining various characteristics of these nanocomposites, including clay‐layer spacings, out‐of‐plane clay‐sheet bending energies, X‐ray diffractograms, and materials properties. This model of clay–polymer interactions is based on a three‐level approach, which uses quantum mechanical and atomistic descriptions to derive a coarse‐grained yet chemically specific representation that can resolve processes on hitherto inaccessible length and time scales. The approach is applied to study collections of clay mineral tactoids interacting with two synthetic polymers, poly(ethylene glycol) and poly(vinyl alcohol). The controlled behavior of layered materials in a polymer matrix is centrally important for many engineering and manufacturing applications. This approach opens up a route to computing the properties of complex soft materials based on knowledge of their chemical composition, molecular structure, and processing conditions.
Organocatalytic Enantioselective Sulfur‐Michael Addition of Thioacetic Acid to Arylmethylidenemalonates
Authors: Wang Renchao , Liu Jing , Xu Jiaxi
Published: December 2014

An organocatalytic enantioselective sulfur‐Michael addition of thioacetic acid to arylmethylidenemalonates was developed with high yields and up to 97% enantiomeric excess. Both enantiomers of the products were accessible with two different organocatalysts. The current method provides the first, practical, and convenient preparation of enantiomerically enriched acetylthiomethylmalonate derivatives.

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Utilizing Mor‐DalPhos/Palladium‐Catalyzed Monoarylation in the Multicomponent One‐Pot Synthesis of Indoles
Authors: Rotta‐Loria Nicolas L. , Borzenko Andrey , Alsabeh Pamela G. , Lavery Christopher B. , Stradiotto Mark
Published: December 2014

The application of a Mor‐DalPhos/palladium catalyst system in the one‐pot, multicomponent assembly of substituted indoles from ortho‐chlorohaloarenes, alkyl ketones (including acetone), and primary amines is reported. The described protocols offer improved substrate scope in all three reaction components, under more mild conditions and without the need for an additional drying agent. Also reported are the first examples of such multicomponent reactions where all reactants are combined at the start of the reaction, without the need for inert atmosphere reaction conditions.

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Low mineral density of a weight‐bearing bone among adult women in a high fertility population
Authors: Stieglitz Jonathan , Beheim Bret A. , Trumble Benjamin C. , Madimenos Felicia C. , Kaplan Hillard , Gurven Michael
Published: December 2014

Evolutionary theories of aging posit that greater reproductive effort causes somatic decline given a fundamental trade‐off between investing energy in reproduction and repair. Few studies in high fertility human populations support this hypothesis, and problems of phenotypic correlation can obscure the expected trade‐off between reproduction and somatic condition. This cross‐sectional study investigates whether greater reproductive effort is associated with reduced calcaneal bone mineral density (BMD) among female Tsimane forager‐farmers of lowland Bolivia. We also investigate whether female Tsimane BMD values are lower than sex‐ and age‐matched US reference values, despite the fact that Tsimane engage in higher physical activity levels that can increase mechanical loading. To measure calcaneal BMD, quantitative ultrasonography was performed on 130 women (mean ± SD age = 36.6 ± 15.7, range = 15–75) that were recruited regardless of past or current reproductive status. Anthropometric and demographic data were collected during routine medical exams. As predicted, higher parity, short inter‐birth interval, and earlier age at first birth are associated with reduced BMD among Tsimane women after adjusting for potential confounders. Population‐level differences are apparent prior to the onset of reproduction, and age‐related decline in BMD is greater among Tsimane compared with American women. Greater cumulative reproductive burden may lower calcaneal BMD individually and jointly with other lifestyle and heritable factors. Fitness impacts of kin transfers in adulthood may determine the value of investments in bone remodeling, and thus affect selection on age‐profiles of bone mineral loss. Am J Phys Anthropol 156:637–648, 2015. © 2014 Wiley Periodicals, Inc.
Self‐Assembly Structure Formation during the Digestion of Human Breast Milk
Authors: Salentinig Stefan , Phan Stephanie , Hawley Adrian , Boyd Ben J.
Published: December 2014

An infant′s complete diet, human breast milk, is the basis for its survival and development. It contains water‐soluble and poorly water‐soluble bioactive components, metabolic messages, and energy, all of which are made bioavailable during the digestion process in the infant′s gastrointestinal tract. Reported is the first discovery of highly geometrically organized structures formed during the digestion of human breast milk under simulated in vivo conditions using small‐angle X‐ray scattering and cryogenic transmission electron microscopy. Time of digestion, pH, and bile salt concentration were found to have symbiotic effects gradually tuning the oil‐based environment inside the breast milk globules to more water‐like structures with high internal surface area. The structure formation is necessarily linked to its function as carriers for poorly water‐soluble molecules in the digestive tract of the infant.
Particle‐Stabilized Water Droplets that Sprout Millimeter‐Scale Tubes
Authors: Graužinytė Miglė , Forth Joe , Rumble Katherine A. , Clegg Paul S.
Published: December 2014

Millimeter‐scale tubes are observed to sprout from water droplets injected into a bath of toluene containing ethanol and silica colloids. This phenomenon requires that first a membrane is formed by the colloids which self‐assemble at the droplet interface, and second, that the ethanol preferentially partitions into the aqueous phase leading to an internal over‐pressure. Tube growth, eruption, and shuffling droplets are subsequently observed, depending on the concentration of ethanol and colloids selected. This work opens many possibilities in the field of biomimetic droplets for fundamental studies of artificial growth at the microscale and for emulsion‐related applications.
Addition of Nitromethane to a Disilene and a Digermene: Comparison to Surface Reactivity and the Facile Formation of 1,3,2‐Dioxazolidines
Authors: Tashkandi Nada Y. , Parsons Frederick , Guo Jiacheng , Baines Kim M.
Published: December 2014

The addition of nitromethane to tetramesityldisilene and tetramesityldigermene leads to the formation of the novel 1,3,2,4,5‐dioxazadisil‐ and digermolidine ring systems, respectively. The 1,3,2,4,5‐dioxazadisilolidine isomerizes to the 1,4,2,3,5‐dioxazadisilolidine ring system, whereas the 1,3,2,4,5‐dioxazadigermolidine undergoes ring opening to the isomeric oxime. The preferential formation of the 1,3,2,4,5‐dioxazadisilolidine, and its rearrangement to a 1,4,2,3,5‐dioxazadisilolidine, provides support for the suggested reaction pathway between nitromethane and the Si(100) 2×1 reconstructed surface.
Excited‐State Charge Separation in the Photochemical Mechanism of the Light‐Driven Enzyme Protochlorophyllide Oxidoreductase
Authors: Heyes Derren J. , Hardman Samantha J. O. , Hedison Tobias M. , Hoeven Robin , Greetham Greg M. , Towrie Michael , Scrutton Nigel S.
Published: December 2014

The unique light‐driven enzyme protochlorophyllide oxidoreductase (POR) is an important model system for understanding how light energy can be harnessed to power enzyme reactions. The ultrafast photochemical processes, essential for capturing the excitation energy to drive the subsequent hydride‐ and proton‐transfer chemistry, have so far proven difficult to detect. We have used a combination of time‐resolved visible and IR spectroscopy, providing complete temporal resolution over the picosecond–microsecond time range, to propose a new mechanism for the photochemistry. Excited‐state interactions between active site residues and a carboxyl group on the Pchlide molecule result in a polarized and highly reactive double bond. This so‐called “reactive” intramolecular charge‐transfer state creates an electron‐deficient site across the double bond to trigger the subsequent nucleophilic attack of NADPH, by the negatively charged hydride from nicotinamide adenine dinucleotide phosphate. This work provides the crucial, missing link between excited‐state processes and chemistry in POR. Moreover, it provides important insight into how light energy can be harnessed to drive enzyme catalysis with implications for the design of light‐activated chemical and biological catalysts.
Magnetic Memory in an Isotopically Enriched and Magnetically Isolated Mononuclear Dysprosium Complex
Authors: Pointillart Fabrice , Bernot Kevin , Golhen Stéphane , Le Guennic Boris , Guizouarn Thierry , Ouahab Lahcène , Cador Olivier
Published: December 2014

The influence of nuclear spin on the magnetic hysteresis of a single‐molecule is evidenced. Isotopically enriched DyIII complexes are synthesized and an isotopic dependence of their magnetic relaxation is observed. This approach is coupled with tuning of the molecular environment through dilution in an amorphous or an isomorphous diamagnetic matrix. The combination of these approaches leads to a dramatic enhancement of the magnetic memory of the molecule. This general recipe can be efficient for rational optimization of single‐molecule magnets (SMMs), and provides an important step for their integration into molecule‐based devices.