bluuebunny/crossref_metadata_2025_split huggingface dataset:
Embryotoxicity assessment of developmental neurotoxicants using a neuronal endpoint in the embryonic stem cell test
Authors: Baek Dae Hyun , Kim Tae Gyun , Lim Hwa Kyung , Kang Jin Wook , Seong Su Kyoung , Choi Seung Eun , Lim So Yun , Park Sung Hee , Nam Bong‐hyun , Kim Eun Hee , Kim Mun Sin , Park Kui Lea 
Published: December 2011

ABSTRACTThe embryonic stem cell test (EST) is a validated in vitro embryotoxicity test; however, as the inhibition of cardiac differentiation alone is used as a differentiation endpoint in the EST, it may not be a useful test to screen embryotoxic chemicals that affect the differentiation of noncardiac tissues. Previously, methylmercury (MeHg), cadmium and arsenic compounds, which are heavy metals that induce developmental neurotoxicity in vivo, were misclassified as nonembryotoxic with the EST. The aim of this study was to improve the EST to correctly screen such developmental neurotoxicants. We developed a neuronal endpoint (Tuj‐1 ID50) using flow cytometry analysis of Tuj‐1‐positive cells to screen developmental neurotoxicants (MeHg, valproic acid, sodium arsenate and sodium arsenite) correctly using an adherent monoculture differentiation method. Using Tuj‐1 ID50 in the EST instead of cardiac ID50, all of the tested chemicals were classified as embryotoxic, while the negative controls were correctly classified as nonembryotoxic. To support the validity of Tuj‐1 ID50, we compared the results from two experimenters who independently tested MeHg using our modified EST. An additional neuronal endpoint (MAP2 ID50), obtained by analyzing the relative quantity of MAP2 mRNA, was used to classify the same chemicals. There were no significant differences in the three endpoint values of the two experimenters or in the classification results, except for isoniazid. In conclusion, our results indicate that Tuj‐1 ID50 can be used as a surrogate endpoint of the traditional EST to screen developmental neurotoxicants correctly and it can also be applied to other chemicals. Copyright © 2011 John Wiley & Sons, Ltd.
Ultrastructural changes in the ovary cells of engorged Rhipicephalus sanguineus female ticks treated with esters of ricinoleic acid from castor oil (Ricinus communis)
Authors: Sampieri Bruno Rodrigues , Arnosti André , Nunes Pablo Henrique , Furquim Karim Christina Scopinho , Chierice Gilberto Orivaldo , Mathias Maria Izabel Camargo 
Published: December 2011

AbstractRhipicephalus sanguineus is a widely distributed tick species that has adapted to the urban environment, and the dog is its main host. This species is also known as a vector and reservoir of diseases caused by bacteria, protozoa, and viruses. Currently, acaricides of synthetic chemical origin have been widely and indiscriminately used, leading to the development of resistance to these products by ticks and causing damage to the environment. Thus, these issues have made it necessary to seek other forms of controlling these ectoparasites. R. sanguineus was artificially infested in host New Zealand White rabbits, which were divided into four treatment groups: control (CG1 and CG2) and treatment (TG1 and TG2) groups. TG1 and TG2 hosts were provided with feed supplemented with esters of ricinoleic acid from castor oil at a concentration of 5 g/kg of feed for 7 and 15 days. Afterward, the ovaries of the female ticks were removed for analysis by transmission electron microscopy. The results showed ultrastructural changes in the somatic and germ cells of ovaries from TG1 and TG2 females, particularly with respect to chorion deposition, a protective membrane of the oocyte, as well as in the transport process of vitellogenic materials via the hemolymph and pedicel cells. Moreover, the mitochondria were less electron‐dense and had cristae that were more disorganized than the mitochondria from CG1 and CG2 individuals. Thus, this study demonstrated the action of esters on the ovaries of R. sanguineus, signaling the prospect of a way to control this ectoparasite without affecting nontarget organisms or the environment. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Recent trends of nitrogen flow of typical agro‐ecosystems in China—major problems and potential solutions
Authors: Liu Chen , Wang Qinxue , Yang Yonghui , Wang Kelin , Ouyang Zhu , Li Yan , Lei Alin , Yasunari Tetsuzo 
Published: December 2011

AbstractBACKGROUND: To diagnose problems that threaten regional sustainability and to devise appropriate treatment measures in China's agro‐ecosystems, a study was carried out to quantify the nitrogen (N) flow in China's typical agro‐ecosystems and develop potential solutions to the increasing environmental N load.RESULTS: The analysis showed that owing to human activity in the agro‐ecosystems of Changjiang River Basin the mean total input of anthropogenic reactive N (i.e. chemical fertiliser, atmospheric deposition and bio‐N fixation) increased from 4.41 × 109 kg‐N in 1980 to 7.61 × 109 kg‐N in 1990 and then to 1.43 × 1010 kg‐N in 2000, with chemical fertiliser N being the largest contributor to N load. Field investigation further showed that changes in human behaviour and rural urbanisation have caused rural communities to become more dependent on chemical fertilisers. In rural regions, around 4.17 kg‐N of per capita annual potential N load as excrement was returned to farmlands and 1.38 kg‐N directly discharged into river systems, while in urbanised regions, around 1.00 kg‐N of per capita annual potential N load as excrement was returned to farmlands and 5.62 kg‐N discharged into river systems in urban areas.CONCLUSION: The findings of the study suggest that human activities have significantly altered the N cycle in agro‐ecosystems of China. With high population density and scarce per capita water resources, non‐point source pollution from agro‐ecosystems continues to put pressure on aquatic ecosystems. Increasing the rate of organic matter recycling and fertiliser efficiency with limited reliance on chemical fertilisers might yield tremendous environmental benefits. Copyright © 2011 Society of Chemical Industry
Synthesis and applications of a novel supramolecular polymer network with multiple H‐bonded melamine pendants and uracil crosslinkers
Authors: Patra Dhananjaya , Ramesh Mohan , Sahu Duryodhan , Padhy Harihara , Chu Chih‐Wei , Wei Kung‐Hwa , Lin Hong‐Cheu 
Published: December 2011

AbstractA conjugated main‐chain copolymer (PBT) consisting of bithiazole, dithieno[3,2‐b:2′,3′‐d]pyrroles (DTP), and pendent melamine units was synthesized by Stille polymerization, which can be hydrogen‐bonded (H‐bonded) with proper molar amounts of bi‐functional π‐conjugated crosslinker F (i.e., two uracil motifs covalently attached to a fluorene core through triple bonds symmetrically) to develop a novel supramolecular polymer network (PBT/F). The effects of multiple H‐bonds on light harvesting capabilities, HOMO levels, and photovoltaic properties of polymer PBT and H‐bonded polymer network PBT/F are investigated. The formation of supramolecular polymer network (PBT/F) between PBT and F was confirmed by FTIR and XRD measurements. Because of the stronger light absorption, lower HOMO level, and higher crystallinity of H‐bonded polymer network PBT/F, the solar cell device containing PBT/F showed better photovoltaic properties than that containing polymer PBT. The preliminary results show that the solar cell device containing 1:1 weight ratio of PBT/F and [6,6]‐phenyl C71 butyric acid methyl ester (PC71BM) offers the best power conversion efficiency (PCE) value of 0.86% with a short‐circuit current density (Jsc) of 4.97 mA/cm2, an open circuit voltage (Voc) of 0.55 V, and a fill factor (FF) of 31.5%. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Limits to model amphoteric defect recombination via SRH statistics
Authors: Steingrube S. , Brendel R. , Altermatt P. P. 
Published: December 2011

AbstractIn semiconductor device modeling, it is common practice to approximate recombination via amphoteric defects by means of the Shockley–Read–Hall (SRH) theory. We show by means of a mathematically rigorous treatment that this approximation is only justified if: (i) the defect distribution of amphoteric defects is approximated by two equally‐shaped energy distributions of acceptor‐ and donor‐like defect states which are separated in energy by the effective correlation energy, (ii) the ratios of the capture cross‐sections (CCS) of free carriers for charged and neutral defect states are strongly asymmetric, (iii) the correlation energy is positive, and (iv) the defect density has its maximum between the quasi‐Fermi levels (QFLs) for the trapped carriers (TQFLs). In particular, we investigate this kind of SRH approximation for the case of injection‐dependent recombination at the interface between crystalline silicon (c‐Si) and amorphous silicon (a‐Si:H), a system that has recently been used to passivate the surface of Si solar cells. It is shown that care must be taken when applying this SRH approximation at low excess carrier densities Δn, e.g., at pn‐junctions between a‐Si:H and c‐Si or at low illumination levels, because the defect distributions may peak outside the TQFLs. We apply a self‐consistent model, which includes the band bending in c‐Si caused by both light‐induced, trapped charges in the a‐Si:H layer and at the a‐Si/c‐Si interface. We show that these trapped charges significantly influence the recombination rate and should be taken into account, as opposed to common practice.
Inability of Human Induced Pluripotent Stem Cell-Hematopoietic Derivatives to Downregulate MicroRNAs In Vivo Reveals a Block in Xenograft Hematopoietic Regeneration
Authors: Risueño Ruth M. , Sachlos Eleftherios , Lee Jong-Hee , Lee Jung Bok , Hong Seok-Ho , Szabo Eva , Bhatia Mickie 
Published: December 2011

Abstract
Hematopoietic stem cells (HSCs) can regenerate the entire hematopoietic system in vivo, providing the most relevant criteria to measure candidate HSCs derived from human embryonic stem cell (hESC) or induced pluripotent stem cell (hiPSC) sources. Here we show that, unlike primitive hematopoietic cells derived from hESCs, phenotypically identical cells derived from hiPSC are more permissive to graft the bone marrow of xenotransplantation recipients. Despite establishment of bone marrow graft, hiPSC-derived cells fail to demonstrate hematopoietic differentiation in vivo. However, once removed from recipient bone marrow, hiPSC-derived grafts were capable of in vitro multilineage hematopoietic differentiation, indicating that xenograft imparts a restriction to in vivo hematopoietic progression. This failure to regenerate multilineage hematopoiesis in vivo was attributed to the inability to downregulate key microRNAs involved in hematopoiesis. Based on these analyses, our study indicates that hiPSCs provide a beneficial source of pluripotent stem cell-derived hematopoietic cells for transplantation compared with hESCs. Since use of the human–mouse xenograft models prevents detection of putative hiPSC-derived HSCs, we suggest that new preclinical models should be explored to fully evaluate cells generated from hiPSC sources.
Disclosure of potential conflicts of interest is found at the end of this article.
Axially homogeneous Rayleigh–Bénard convection in a cylindrical cell
Authors: Schmidt Laura E. , Calzavarini Enrico , Lohse Detlef , Toschi Federico , Verzicco Roberto 
Published: December 2011

AbstractPrevious numerical studies have shown that the ‘ultimate regime of thermal convection’ can be attained in a Rayleigh–Bénard cell when the kinetic and thermal boundary layers are eliminated by replacing both lateral and horizontal walls with periodic boundary conditions (homogeneous Rayleigh–Bénard convection). Then, the heat transfer scales like $\mathit{Nu}\ensuremath{\sim} {\mathit{Ra}}^{1/ 2} $ and turbulence intensity as $\mathit{Re}\ensuremath{\sim} {\mathit{Ra}}^{1/ 2} $, where the Rayleigh number $\mathit{Ra}$ indicates the strength of the driving force (for fixed values of $\mathit{Pr}$, which is the ratio between kinematic viscosity and thermal diffusivity). However, experiments never operate in unbounded domains and it is important to understand how confinement might alter the approach to this ultimate regime. Here we consider homogeneous Rayleigh–Bénard convection in a laterally confined geometry – a small-aspect-ratio vertical cylindrical cell – and show evidence of the ultimate regime as $\mathit{Ra}$ is increased: in spite of the lateral confinement and the resulting kinetic boundary layers, we still find $\mathit{Nu}\ensuremath{\sim} \mathit{Re}\ensuremath{\sim} {\mathit{Ra}}^{1/ 2} $ at $\mathit{Pr}= 1$. Further, it is shown that the system supports solutions composed of modes of exponentially growing vertical velocity and temperature fields, with $\mathit{Ra}$ as the critical parameter determining the properties of these modes. Counter-intuitively, in the low-$\mathit{Ra}$ regime, or for very narrow cylinders, the numerical simulations are susceptible to these solutions, which can dominate the dynamics and lead to very high and unsteady heat transfer. As $\mathit{Ra}$ is increased, interaction between modes stabilizes the system, evidenced by the increasing homogeneity and reduced fluctuations in the root-mean-square velocity and temperature fields. We also test that physical results become independent of the periodicity length of the cylinder, a purely numerical parameter, as the aspect ratio is increased.
Introduction and spread of non-native parasites withSilurus glanisL. (Teleostei: Siluridae) in UK fisheries
Authors: Reading A.J. , Britton J.R. , Davies G.D. , Shinn A.P. , Williams C.F. 
Published: December 2011

AbstractDespite growing concern of the ecological risks posed by the European catfishSiluris glanisL. in freshwater fisheries, little information exists on the parasite fauna of this silurid catfish in Britain. Parasitological examinations of releasedS. glanisfrom four still-water fisheries in England revealed the presence ofThaparocleidus vistulensis(Siwak, 1932) andErgasilus sieboldi(Nordmann, 1832), both non-native parasites, the latter known to be an important fish pathogen. This represents the first record ofT. vistulensisfrom British freshwater fish. The human-assisted movement ofS. glanisbetween UK recreational still-water fisheries provides a clear avenue for the introduction and spread of non-native parasites.
Epidemiology of acanthocephalan infections in crabs from the Bahía Blanca Estuary, Argentina
Authors: La Sala L.F. , Perez A.M. , Martorelli S.R. 
Published: December 2011

AbstractThis study was conducted in two populations of crabs,Cyrtograpsus angulatusandNeohelice granulatafrom the Bahía Blanca Estuary, in Argentina, to identify risk factors for infection by the acanthocephalanProfilicollis chasmagnathiand to assess the association between infection and mortality of these hosts.Cyrtograpsus angulatusandN. granulatacrabs were sampled seasonally over the course of a year, and spring sampling included collection of dead crabs predated by Olrog's gulls in a nearby breeding colony. Potential risk factors for infection were assessed and the number of cystacanth larvae per crab was counted. InC. angulatus, the odds of infection increased by 7% for each millimetre increase in carapace length, and were nearly 17 times greater in crabs sampled from the Olrog's gull feeding area compared with those sampled from nests in the breeding colony. For every millimetre increase in carapace length inN. granulata, the odds of infection increased by 13% in crabs from the breeding colony, and by 32% in crabs from the feeding area. Mean intensity of infection inN. granulataincreased by 16.5% for each additional millimetre of carapace width. The level of parasite aggregation was lowest in the largestC. angulatusand highest inN. granulatapredated by Olrog's gull. The results show that host size is the most important factor influencing infection prevalence in both crab species and intensity of infection inN. granulata, and suggest the presence of parasite-induced mortality in the populations studied.
Social mobility and the Middle Ages
Authors: CAROCCI SANDRO 
Published: December 2011

ABSTRACTNotwithstanding its relevance, social mobility has not been at the forefront of the agenda for historians of the Middle Ages. The first part of this paper deals with the reasons for this lack of interest, highlighting the role of historical models such as the French ‘feudal revolution’, the neo-Malthusian interpretations, the English commercialisation model and the great narrative of Italian medieval merchants. The second part assesses the extent to which this lack of interest has been challenged by conceptions of social space and social mobility developed in recent decades by sociologists and anthropologists. Therefore, it is really important to indicate the gaps in our understanding, and to clarify research questions, technical problems and methods. The paper examines the constitutive elements of social identities, the plurality of social ladders, and the channels of social mobility. It touches upon the performative role of learned representations, and upon the constraints imposed upon human agency by family practices and genre. It underlines the importance of studying the mobility inside social groups, and argues that we must distinguish between two different types of medieval social mobility: autogenous social mobility, and endogenous or conflictual social mobility.
Deterministic individual-based cellular automata modelling of single species population dynamics
Authors: Kalmykov Lev , Kalmykov Vyacheslav 
Published: December 2011

AbstractThis presentation was created to characterise foundations of cellular automata modelling of single species population dynamics. We show models of single species population growth based on deterministic birth-death-regeneration process and demonstrate a relationship between fecundity rate and population growth rate. Our models provide mechanistic simulation of logistic-like and double logistic-like curves of population growth that is not possible in the classical Verhulst model (logistic growth model). This method is deterministic individual-based and is based on logical “if-then” statements only. As this method is bottom-up mechanistic and provides a direct visual insight into dynamics of complex systems, we used it to study mechanisms of interspecific competition in further experiments.
The Constraints to Escaping Rural Poverty: An Analysis of the Complementarities of Assets in Developing Countries
Authors: Foster William , Valdés Alberto , Davis Benjamin , Anríquez Gustavo 
Published: December 2011

AbstractBased on Food and Agriculture Organization data for 15 developing countries, we examine household characteristics, asset bundles and income‐generating activities of the rural poor. Assets aid in exiting poverty, not independent of one another, but rather in combination. We develop an approach to estimate the complementarities between education, farm size and infrastructure. Limited access to the three assets of interest here (susceptible to medium‐ and long‐term interventions) might prevent moving a large number of small farmers out of poverty in the short‐term (even with support programs). Increased land holding often has lower poverty‐reducing potential, and when its potential is high, it is in countries where most land is divided among small operations (for example, Bangladesh). Education is confirmed as highly poverty‐alleviating, and has a high complementarity with infrastructure.
Stromal cells from term fetal membrane are highly suppressive in allogeneic settings in vitro
Authors: Karlsson H , Erkers T , Nava S , Ruhm S , Westgren M , Ringdén O 
Published: December 2011

Summary
Bone marrow-derived mesenchymal stromal cells (BM-MSCs) have immunosuppressive properties and have been used to treat steroid-refractory acute graft-versus-host disease (GVHD) in stem cell transplant patients. Cells with similar capacities can also be found in term placental tissue. We have isolated stromal cells from term fetal membrane (FMSCs), umbilical cords (UCSCs) and placental villi (PVSCs) as well as from bone marrow and compared their immunoregulatory capacity in allogeneic settings. We found that FMSCs and UCSCs suppressed proliferation significantly in mixed lymphocyte reactions (MLRs), whereas PVSCs showed inconsistent suppressive effects. When added to MLR cultures, FMSCs suppressed the production of interferon (IFN)-γ and interleukin (IL)-17, whereas UCSCs and PVSCs promoted the production of IL-17 instead. Secretion of IL-10 was increased after addition of FMSCs and UCSCs. In this setting, BM-MSCs had no significant effect on secretion of IFN-γ, IL-17 or IL-10 in MLR cultures. When analysing the expression of adhesion markers, we noted that FMSCs expressed the highest levels of CD29 (β1), CD49d (α4) and CD54 (ICAM-1) compared to the other types of stromal cells. Thus, our data indicate that stromal cells isolated from term fetal membrane have great immunosuppressive capacity in terms of proliferation and production of proinflammatory cytokines from alloreactive T cells, and also promote anti-inflammatory IL-10. They express high levels of integrins that may be of importance in homing to inflamed tissues. Fetal membrane may provide a valuable source of cells with immunosuppressive properties and could possibly be used for treatment of acute GVHD and other inflammatory disorders.
Mesozoic rifting in the Basque–Cantabrian Basin (Spain): Inherited faults, transversal structures and stress perturbation
Authors: Tavani Stefano , Muñoz Josep Anton 
Published: December 2011

Terra Nova, 24, 70–76, 2012AbstractIn the Basque–Cantabrian Basin (Northern Iberian Margin), inherited WNW–ESE‐striking faults were reactivated during the Mesozoic extensional stage associated with the opening of the Bay of Biscay. Syn‐rift structures in the area include different sets, apparently indicating multiple extensional stages. In particular, abundant NE–SW‐striking extensional elements have been interpreted in the past as having developed during a late rifting, left‐lateral transtensional stage. However, the development of these structures also fits well with an analytical model of ridge‐perpendicular extension. Along‐strike stretching imposed by displacement variations along inherited faults locally produced an additional stress field oriented obliquely to the regional one. This caused rotation of the local minimum stress and development of anomalously oriented transversal structures. A single extensional stage is thus inferred during Mesozoic rifting, with a stretching direction oriented approximately perpendicular to the trend of the Bay of Biscay oceanic ridge.