bluuebunny/crossref_metadata_2025 huggingface dataset:
High-Dose Diosgenin Reduces Bone Loss in Ovariectomized Rats via Attenuation of the RANKL/OPG Ratio
Authors: Zhang Zhiguo , Song Changheng , Fu Xiaowei , Liu Meijie , Li Yan , Pan Jinghua , Liu Hong , Wang Shaojun , Xiang Lihua , Xiao Gary , Ju Dahong
Published: September 2014

The aim of this study was to evaluate effect of diosgenin (DG) on rats that had osteoporosis-like features induced by ovariectomy (OVX). Seventy-two six-month-old female Wistar rats were subjected to either ovariectomy (n = 60) or Sham operation (SHAM group, n = 12). Beginning at one week post-ovariectomy, the OVX rats were treated with vehicle (OVX group, n = 12), estradiol valerate (EV group, n = 12), or DG at three doses (DG-L, -M, -H group, n = 12, respectively). After a 12-week treatment, administration of EV or DG-H inhibited OVX-induced weight gain, and administration of EV or DG-H or DG-M had a significantly uterotrophic effect. Bone mineral density (BMD) and indices of bone histomorphometry of tibia were measured. Levels of protein and mRNA expression of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa-B ligand (RANKL) in tibia were evaluated by immunohistochemistry and in situ hybridization. Our results show that DG at a high dose (DG-H) had a significant anti-osteoporotic effect compared to OVX control. DG-H treatment down-regulated expression of RANKL and up-regulated expression of OPG significantly in tibia from OVX rats compared to control, and thus lowered the RANKL/OPG ratio. This suggests that the anti-osteoporotic effect of DG might be associated with modulating the RANKL/OPG ratio and DG had potential to be developed as alternative therapeutic agents of osteoporosis induced by postmenopause.
Additional Evidence of the Trypanocidal Action of (−)-Elatol on Amastigote Forms through the Involvement of Reactive Oxygen Species
Authors: Desoti Vânia , Lazarin-Bidóia Danielle , Sudatti Daniela , Pereira Renato , Ueda-Nakamura Tania , Nakamura Celso , De Oliveira Silva Sueli
Published: September 2014

Chagas’ disease, a vector-transmitted infectious disease, is caused by the protozoa parasite Trypanosoma cruzi. Drugs that are currently available for the treatment of this disease are unsatisfactory, making the search for new chemotherapeutic agents a priority. We recently described the trypanocidal action of (−)-elatol, extracted from the macroalga Laurencia dendroidea. However, nothing has been described about the mechanism of action of this compound on amastigotes that are involved in the chronic phase of Chagas’ disease. The goal of the present study was to evaluate the effect of (−)-elatol on the formation of superoxide anions (O2•−), DNA fragmentation, and autophagy in amastigotes of T. cruzi to elucidate the possible mechanism of the trypanocidal action of (−)-elatol. Treatment of the amastigotes with (−)-elatol increased the formation of O2•− at all concentrations of (−)-elatol assayed compared with untreated parasites. Increased fluorescence was observed in parasites treated with (−)-elatol, indicating DNA fragmentation and the formation of autophagic compartments. The results suggest that the trypanocidal action of (−)-elatol might involve the induction of the autophagic and apoptotic death pathways triggered by an imbalance of the parasite’s redox metabolism.
A Feedback Mechanism to Control Apoptosis Occurs in the Digestive Gland of the Oyster Crassostrea gigas Exposed to the Paralytic Shellfish Toxins Producer Alexandrium catenella
Authors: Rolland Jean-Luc , Medhioub Walid , Vergnes Agnes , Abi-khalil Celina , Savar Véronique , Abadie Eric , Masseret Estelle , Amzil Zouher , Laabir Mohamed
Published: September 2014

To better understand the effect of Paralytic Shellfish Toxins (PSTs) accumulation in the digestive gland of the Pacific oyster, Crassostrea gigas, we experimentally exposed individual oysters for 48 h to a PSTs producer, the dinoflagellate Alexandrium catenella. In comparison to the effect of the non-toxic Alexandrium tamarense, on the eight apoptotic related genes tested, Bax and BI.1 were significantly upregulated in oysters exposed 48 h to A. catenella. Among the five detoxification related genes tested, the expression of cytochrome P450 (CYP1A) was shown to be correlated with toxin concentration in the digestive gland of oysters exposed to the toxic dinoflagellate. Beside this, we observed a significant increase in ROS production, a decrease in caspase-3/7 activity and normal percentage of apoptotic cells in this tissue. Taken together, these results suggest a feedback mechanism, which may occur in the digestive gland where BI.1 could play a key role in preventing the induction of apoptosis by PSTs. Moreover, the expression of CYP1A, Bax and BI.1 were found to be significantly correlated to the occurrence of natural toxic events, suggesting that the expression of these genes together could be used as biomarker to assess the biological responses of oysters to stress caused by PSTs.
Unraveling Biochemical Pathways Affected by Mitochondrial Dysfunctions Using Metabolomic Approaches
Authors: Demine Stéphane , Reddy Nagabushana , Renard Patricia , Raes Martine , Arnould Thierry
Published: September 2014

Mitochondrial dysfunction(s) (MDs) can be defined as alterations in the mitochondria, including mitochondrial uncoupling, mitochondrial depolarization, inhibition of the mitochondrial respiratory chain, mitochondrial network fragmentation, mitochondrial or nuclear DNA mutations and the mitochondrial accumulation of protein aggregates. All these MDs are known to alter the capacity of ATP production and are observed in several pathological states/diseases, including cancer, obesity, muscle and neurological disorders. The induction of MDs can also alter the secretion of several metabolites, reactive oxygen species production and modify several cell-signalling pathways to resolve the mitochondrial dysfunction or ultimately trigger cell death. Many metabolites, such as fatty acids and derived compounds, could be secreted into the blood stream by cells suffering from mitochondrial alterations. In this review, we summarize how a mitochondrial uncoupling can modify metabolites, the signalling pathways and transcription factors involved in this process. We describe how to identify the causes or consequences of mitochondrial dysfunction using metabolomics (liquid and gas chromatography associated with mass spectrometry analysis, NMR spectroscopy) in the obesity and insulin resistance thematic.
Fluorescent Sensors for Biological Applications
Authors: Ai Hui-wang
Published: September 2014

Fluorescence is one of the most important analytical methods used in biological studies. In the past decade or two, instrumentation in this field has greatly advanced, and now it is possible to detect single photons or fluorescent molecules [1,2], or break the Abbe diffraction limit to distinguish two points spaced less than 50 nm apart [3]. Concurrently, the development of improved fluorescent probes, which can be coupled with state-of-the-art instruments, has been equally important. This special issue on “fluorescent biosensors” in Sensors reports recent results from eight research groups in the field of sensor development. It includes three review articles, and six research articles reporting original results. [...]
The relative and absolute frequencies of angiosperm sexual systems: Dioecy, monoecy, gynodioecy, and an updated online database
Authors: Renner Susanne S.
Published: September 2014

• Premise of the study: Separating sexual function between different individuals carries risks, especially for sedentary organisms. Nevertheless, many land plants have unisexual gametophytes or sporophytes. This study brings together data and theoretical insights from research over the past 20 yr on the occurrence and frequency of plant sexual systems, focusing on the flowering plants.

• Methods: A list of genera with dioecious species, along with other information, is made available (http://www.umsl.edu/∼renners/). Frequencies of other sexual systems are tabulated, and data on the genetic regulation, ecological context, and theoretical benefits of dioecy reviewed.

• Key results: There are 15600 dioecious angiosperms in 987 genera and 175 families, or 5–6% of the total species (7% of genera, 43% of families), with somewhere between 871 to 5000 independent origins of dioecy. Some 43% of all dioecious angiosperms are in just 34 entirely dioecious clades, arguing against a consistent negative influence of dioecy on diversification. About 31.6% of the dioecious species are wind‐pollinated, compared with 5.5–6.4% of nondioecious angiosperms. Also, 1.4% of all angiosperm genera contain dioecious and monoecious species, while 0.4% contain dioecious and gynodioecious species. All remaining angiosperm sexual systems are rare. Chromosomal sex determination is known from 40 species; environmentally modulated sex allocation is common. Few phylogenetic studies have focused on the evolution of dioecy.

• Conclusions: The current focus is on the genetic mechanisms underlying unisexual flowers and individuals. Mixed strategies of sexual and vegetative dispersal, together with plants’ sedentary life style, may often favor polygamous systems in which sexually inconstant individuals can persist. Nevertheless, there are huge entirely dioecious clades of tropical woody plants.
Understanding the Developmental Course of the Acoustic Properties of the Human Outer and Middle Ear Over the First 6 Months of Life by Using a Longitudinal Analysis of Power Reflectance at Ambient Pressure
Authors: Shahnaz Navid , Cai Anika , Qi Li
Published: September 2014

Background:As shown by tympanometric and wideband acoustic immittance (WAI) measures, developmental changes that occur in the middle ear and the external auditory canal can affect the mechano-acoustic properties of the middle ear system during the first 2 years of life. However,
these observed differences and the specific course of maturation have not been fully investigated.Purpose:The overall goal of the current study was to define the time course and rate at which functional maturation of the middle ear occurs in human infants through wideband acoustic immittance
(WAI). It was also within the scope of this study to establish normative data to characterize acoustic properties of the normal middle ear in infants from birth to 6 mo of age.Research Design:Newborns were tested longitudinally at 1-mo intervals up to 6 mo of age for a total of six
visits. All babies passed transient evoked otoacoustic emission screening on each visit. Tympanograms and WAI were recorded, and the distributions of WAI patterns were analyzed as a function of age. WAI was measured across a wide range of frequencies from birth to 6 mos of age in a cohort
of 31 infants. Test-retest differences for WAI were also evaluated.Study Sample:Thirty-one newborns were recruited.Data Collection and Analysis:A repeated-measure analysis of variance was conducted to investigate whether the variations observed in power reflectance at ambient
pressure across the six visits were statistically different. All significant findings were subject to Greenhouse-Geisser correction for repeated-measures sphericity and inflated type-I error.Results:Results showed that power reflectance increased (closer to 1) at low frequencies (<400
Hz) and decreased (closer to 0) at high frequencies (>2000 Hz) as a function of age. There was very little change in power reflectance from 600 to 1600 Hz across the first 6 mo of life. Most group changes that were observed were also consistently shown in longitudinal changes observed within
individual subjects.Conclusions:The overall maturation of the middle ear can result in a lower reflectance at higher frequencies and a higher reflectance at lower frequencies. This could be explained by known changes in ear-canal and/or middle-ear structures across this time period,
which could lead to changes in mass and resistance. An increase in volume in the middle-ear cavity, reduction of middle-ear debris, and overall decrease in resistive elements might be contributing to these changes. Significant differences were observed between each visit, which could warrant
the use of age-specific norms when applying WAI data to infants less than 6 mo of age.
Sphères de reconnaissance
Authors: Abel Olivier
Published: September 2014

L’idée de reconnaissance désamorce ce qu’une posture de dénonciation pourrait avoir de purement extérieur, pour penser les liens de l’intérieur. Et si la dénonciation est portée par l’idéal d’émancipation, la reconnaissance sait l’importance des attachements. Mais la reconnaissance ne saurait retomber dans une forme de quiétude trop apaisée, trop crédule aux médiations et réconciliations. Il doit rester une sorte d’inquiétude critique, elle-même mise en émoi par toutes les formes du déni de reconnaissance : le sentiment de méconnaissance à cet égard restera un sûr guide du travail de reconnaissance. Nous sommes notamment très focalisés sur l’injustice comprise comme inégalité économique, et sur la violence et la domination dans des rapports de force. Mais nous n’accordons peut-être pas assez d’importance à l’humiliation d’être sans parole ni estime de soi. La pluralité des registres de la vie sociale, avoir, pouvoir, valoir, exposée très tôt dans l’œuvre de Ricœur, nous aidera ainsi à élargir l’amplitude de la reconnaissance, jusqu’à lui restituer son sens épique.
Access to Information
Authors: Sousa Monica Teresa , Bento Leonardo Valles
Published: September 2014

Right to information means the right of citizens to have access to information produced by, or held by, public/governmental agencies. This chapter intends to analyze the legal grounds of the right to access to information in Brazil as compared to the best international practice. One of the main risks to good governance and democracy is the use of public resources for private purposes, and the development of new communication technologies, especially the Internet, has revolutionized the manner in which the public interacts with the information available, impacting democratic practices. In November 2011, the adoption of Federal Law 12,527 made Brazil the 89th country in the world, and the 19th in Latin America, to adopt specific legislation implementing the right to access to public information. In Brazil, public authorities, especially the courts, tend to accept easily the allegations of violation of privacy and defamation of those whose interests are harmed or threatened by the broadcasting of information. In the conflict between access to information and private interests, the latter has prevailed. In this context, the Access to Information Law has become a relevant policy to the Brazilian civil society to strengthen and consolidate a democratic political culture and promote institutional maturity.
Convergence of Nanotechnology and Microbiology
Authors: Khanday Mussrat Fayaz
Published: September 2014

The convergence of nanotechnology with microbiology is a nifty interdisciplinary research area that could amplify the limits of technology, enhance global health through formation of different drugs that can be effective against different infectious diseases, and for treatment of drinking water to kill the pathogens and make it safe for public use. Bacteria, fungi, actinomycetes, and plants have been successfully used for the formation of nanoparticles of silver, gold, zinc, etc. As the microorganisms, especially bacteria, are becoming resistant to the commonly used antibiotics, an alternative antimicrobial agent that can be effective against the antibiotic-resistant bacteria is needed. In the present chapter, the author highlights the relationship between these two mighty disciplines. The chapter deals with many aspects like antimicrobial activity of nanoparticles, formation of nanoparticles using microorganisms, etc. The green synthesis of nanoparticles is emerging as a new field of science; hence, it is discussed in detail.
Comparative Study of Computational Methods for Reconstructing Genetic Networks of Cancer-Related Pathways
Authors: Sedaghat Nafiseh , Saegusa Takumi , Randolph Timothy , Shojaie Ali
Published: September 2014

Network reconstruction is an important yet challenging task in systems biology. While many methods have been recently proposed for reconstructing biological networks from diverse data types, properties of estimated networks and differences between reconstruction methods are not well understood. In this paper, we conduct a comprehensive empirical evaluation of seven existing network reconstruction methods, by comparing the estimated networks with different sparsity levels for both normal and tumor samples. The results suggest substantial heterogeneity in networks reconstructed using different reconstruction methods. Our findings also provide evidence for significant differences between networks of normal and tumor samples, even after accounting for the considerable variability in structures of networks estimated using different reconstruction methods. These differences can offer new insight into changes in mechanisms of genetic interaction associated with cancer initiation and progression.
Integrated Analysis of Whole-Genome Paired-End and Mate-Pair Sequencing Data for Identifying Genomic Structural Variations in Multiple Myeloma
Authors: Yang Rendong , Chen Li , Newman Scott , Gandhi Khanjan , Doho Gregory , Moreno Carlos S. , Vertino Paula M. , Bernal-Mizarchi Leon , Lonial Sagar , Boise Lawrence H. , Rossi Michael , Kowalski Jeanne , Qin Zhaohui S.
Published: September 2014

We present a pipeline to perform integrative analysis of mate-pair (MP) and paired-end (PE) genomic DNA sequencing data. Our pipeline detects structural variations (SVs) by taking aligned sequencing read pairs as input and classifying these reads into properly paired and discordantly paired categories based on their orientation and inferred insert sizes. Recurrent SV was identified from the discordant read pairs. Our pipeline takes into account genomic annotation and genome repetitive element information to increase detection specificity. Application of our pipeline to whole-genome MP and PE sequencing data from three multiple myeloma cell lines (KMS11, MM.1S, and RPMI8226) recovered known SVs, such as heterozygous TRAF3 deletion, as well as a novel experimentally validated SPI1 - ZNF287 inter-chromosomal rearrangement in the RPMI8226 cell line.
A Bayesian Integrative Model for Genetical Genomics with Spatially Informed Variable Selection
Authors: Cassese Alberto , Guindani Michele , Vannucci Marina
Published: September 2014

We consider a Bayesian hierarchical model for the integration of gene expression levels with comparative genomic hybridization (CGH) array measurements collected on the same subjects. The approach defines a measurement error model that relates the gene expression levels to latent copy number states. In turn, the latent states are related to the observed surrogate CGH measurements via a hidden Markov model. The model further incorporates variable selection with a spatial prior based on a probit link that exploits dependencies across adjacent DNA segments. Posterior inference is carried out via Markov chain Monte Carlo stochastic search techniques. We study the performance of the model in simulations and show better results than those achieved with recently proposed alternative priors. We also show an application to data from a genomic study on lung squamous cell carcinoma, where we identify potential candidates of associations between copy number variants and the transcriptional activity of target genes. Gene ontology (GO) analyses of our findings reveal enrichments in genes that code for proteins involved in cancer. Our model also identifies a number of potential candidate biomarkers for further experimental validation.
Functional Annotation of Putative Regulatory Elements at Cancer Susceptibility Loci
Authors: Rosse Stephanie A. , Auer Paul L. , Carlson Christopher S.
Published: September 2014

Most cancer-associated genetic variants identified from genome-wide association studies (GWAS) do not obviously change protein structure, leading to the hypothesis that the associations are attributable to regulatory polymorphisms. Translating genetic associations into mechanistic insights can be facilitated by knowledge of the causal regulatory variant (or variants) responsible for the statistical signal. Experimental validation of candidate functional variants is onerous, making bioinformatic approaches necessary to prioritize candidates for laboratory analysis. Thus, a systematic approach for recognizing functional (and, therefore, likely causal) variants in noncoding regions is an important step toward interpreting cancer risk loci. This review provides a detailed introduction to current regulatory variant annotations, followed by an overview of how to leverage these resources to prioritize candidate functional polymorphisms in regulatory regions.
Effects of Fibrosis Morphology on Reentrant Ventricular Tachycardia Inducibility and Simulation Fidelity in Patient-Derived Models
Authors: Ringenberg Jordan , Deo Makarand , Filgueiras-Rama David , Pizarro Gonzalo , Ibañez Borja , Peinado Rafael , Merino José L. , Berenfeld Omer , Devabhaktuni Vijay
Published: September 2014

Myocardial fibrosis detected via delayed-enhanced magnetic resonance imaging (MRI) has been shown to be a strong indicator for ventricular tachycardia (VT) inducibility. However, little is known regarding how inducibility is affected by the details of the fibrosis extent, morphology, and border zone configuration. The objective of this article is to systematically study the arrhythmogenic effects of fibrosis geometry and extent, specifically on VT inducibility and maintenance. We present a set of methods for constructing patient-specific computational models of human ventricles using in vivo MRI data for patients suffering from hypertension, hypercholesterolemia, and chronic myocardial infarction. Additional synthesized models with morphologically varied extents of fibrosis and gray zone (GZ) distribution were derived to study the alterations in the arrhythmia induction and reentry patterns. Detailed electrophysiological simulations demonstrated that (1) VT morphology was highly dependent on the extent of fibrosis, which acts as a structural substrate, (2) reentry tended to be anchored to the fibrosis edges and showed transmural conduction of activations through narrow channels formed within fibrosis, and (3) increasing the extent of GZ within fibrosis tended to destabilize the structural reentry sites and aggravate the VT as compared to fibrotic regions of the same size and shape but with lower or no GZ. The approach and findings represent a significant step toward patient-specific cardiac modeling as a reliable tool for VT prediction and management of the patient. Sensitivities to approximation nuances in the modeling of structural pathology by image-based reconstruction techniques are also implicated.
Unemployment: natural rate epicycles or hysteresis?*
Authors: Cross Rod
Published: September 2014

This paper argues that the natural rate of unemployment hypothesis, in which equilibrium unemployment is determined by ‘structural’ variables alone, is wrong: it is both implausible and inconsistent with the evidence. Instead, equilibrium unemployment is haunted by hysteresis. The curious history of the natural rate hypothesis is considered, curious because the authors of the hypothesis thought hysteresis to be relevant. The various methods that have been used to model hysteresis in economic systems are outlined, including the Preisach model with its selective, erasable memory properties. The evidence regarding hysteresis effects on output and unemployment is then reviewed.
Restructuring finance to promote productive employment
Authors: Epstein Gerald
Published: September 2014

Modern financial markets and institutions have grown massively in relation to the economy in the United States and elsewhere, and there is little evidence that in recent years their contributions to economic and social output justify the resources they capture and the risks they impose on society. Many policy options exist to limit finance’s destructive excesses and to shrink its size. But while these efforts are important, more proactive measures to redirect financial activity is likely to be needed to achieve key social goals, such as employment generation and a successful transition to a fossil fuel limited economy. Refocusing financial institutions and financial activities toward providing investments in renewable energy and energy conservation provide an important example of reformed financial activity that both generate more and decent employment, while contributing to the production of key social goods. Abandoning the decades-long embrace of speculative finance and promoting socially efficient finance instead is a key imperative facing the United States and many other countries who adopted financial liberalization in the late twentieth century, with costly results.
High-resolution ice thickness and bed topography of a land-terminating section of the Greenland Ice Sheet
Authors: Lindbäck K. , Pettersson R. , Doyle S. H. , Helanow C. , Jansson P. , Kristensen S. S. , Stenseng L. , Forsberg R. , Hubbard A. L.
Published: September 2014

Abstract. We present ice thickness and bed topography maps with a high spatial resolution (250–500 m) of a land-terminating section of the Greenland Ice Sheet derived from ground-based and airborne radar surveys. The data have a total area of ~12 000 km2 and cover the whole ablation area of the outlet glaciers of Isunnguata Sermia, Russell, Leverett, Ørkendalen and Isorlersuup up to the long-term mass balance equilibrium line altitude at ~1600 m above sea level. The bed topography shows highly variable subglacial trough systems, and the trough of Isunnguata Sermia Glacier is overdeepened and reaches an elevation of ~500 m below sea level. The ice surface is smooth and only reflects the bedrock topography in a subtle way, resulting in a highly variable ice thickness. The southern part of our study area consists of higher bed elevations compared to the northern part. The compiled data sets of ground-based and airborne radar surveys cover one of the most studied regions of the Greenland Ice Sheet and can be valuable for detailed studies of ice sheet dynamics and hydrology. The combined data set is freely available at doi:10.1594/pangaea.830314.
A framework for benchmarking of homogenisation algorithm performance on the global scale
Authors: Willett K. , Williams C. , Jolliffe I. T. , Lund R. , Alexander L. V. , Brönnimann S. , Vincent L. A. , Easterbrook S. , Venema V. K. C. , Berry D. , Warren R. E. , Lopardo G. , Auchmann R. , Aguilar E. , Menne M. J. , Gallagher C. , Hausfather Z. , Thorarinsdottir T. , Thorne P. W.
Published: September 2014

Abstract. The International Surface Temperature Initiative (ISTI) is striving towards substantively improving our ability to robustly understand historical land surface air temperature change at all scales. A key recently completed first step has been collating all available records into a comprehensive open access, traceable and version-controlled databank. The crucial next step is to maximise the value of the collated data through a robust international framework of benchmarking and assessment for product intercomparison and uncertainty estimation. We focus on uncertainties arising from the presence of inhomogeneities in monthly mean land surface temperature data and the varied methodological choices made by various groups in building homogeneous temperature products. The central facet of the benchmarking process is the creation of global-scale synthetic analogues to the real-world database where both the "true" series and inhomogeneities are known (a luxury the real-world data do not afford us). Hence, algorithmic strengths and weaknesses can be meaningfully quantified and conditional inferences made about the real-world climate system. Here we discuss the necessary framework for developing an international homogenisation benchmarking system on the global scale for monthly mean temperatures. The value of this framework is critically dependent upon the number of groups taking part and so we strongly advocate involvement in the benchmarking exercise from as many data analyst groups as possible to make the best use of this substantial effort.
A new synthesis for terrestrial nitrogen inputs
Authors: Houlton B. Z. , Morford S. L.
Published: September 2014

Abstract. Nitrogen (N) inputs sustain many different aspects of local soil processes, their services, and their interactions with the broader Earth system. We present a new synthesis for terrestrial N inputs that considers both rock and atmospheric sources. We review evidence for state-factor regulation over biological N fixation, deposition and rock weathering inputs from local to global scales and in transient vs. steady-state landscapes. Our framework highlights strong organism and topographic (relief) controls over all three N input pathways, with the anthropogenic factor clearly important in rising N deposition rates. In addition, the climate, parent material and time factors are shown to influence patterns of fixation and rock-weathering inputs of N in diverse soil-systems. Data reanalysis suggests that weathering of N-rich parent material could resolve several known cases of "missing N inputs" in ecosystems, and demonstrates how the inclusion of rock N sources into modern concepts can lead to a richer understanding of spatial and temporal patterns of ecosystem N availability. For example, explicit consideration of rock N inputs into classic pedogenic models (e.g., Walker and Syers model) yields a fundamentally different expectation from the standard case: weathering of N-rich parent material could enhance N availability and facilitate terrestrial succession in developmentally young sites even in the absence of N-fixing organisms. We conclude that a state-factor framework for N complements our growing understanding multiple-source controls on phosphorus and cation availability in Earth's soil; but with significant exceptions given the lack of an N fixation analogue in all other biogeochemical cycles. Rather, a state-factor analysis of N must recognize non-symmetrical feedbacks among input pathways, whereby high N inputs via deposition or rock weathering have the potential to reduce biological fixation rates within a given state-factor.
Some properties of testicular hyaluronidases
Authors: Enkhmaa Ts , Purev D , Bayarmaa J
Published: September 2014

The properties (pHopt, Topt, Km, temperature, acid and base stability of the enzyme activity) of hyaluronidase prepared from testes of bovine, horse, pig and antelope were determined.DOI: http://dx.doi.org/10.5564/mjc.v12i0.169 Mongolian Journal of Chemistry Vol.12 2011: 38-41
Coumarins from Peucedanum hystrix growing in Mongolia
Authors: Ganbaatar J , Shults EE , Otgonsuren D , Radnaeva LD , Taraskin B , Badamkhand D
Published: September 2014

It is proved to be that of genus Peucedanum hystrix serve as a source of biologically valuable natural coumarins. Nine angular furocoumarins belonging to class of 2'-substituted and 2',3'-disubstituted 2',3'-dihydrofurocoumarins have been isolated and structurally isolated. For peucenidin data of X-ray analysis is obtained.DOI: http://dx.doi.org/10.5564/mjc.v12i0.170 Mongolian Journal of Chemistry Vol.12 2011: 42-49
Chemical and biological investigation of the Agaricus silvaticus Schaeff ex. Secr
Authors: Munkhgerel L , Erdenechimeg N , Dumaa M , Zhang G , Odonmajig P , Regdel D
Published: September 2014

Extract of Agaricus silvaticus Schaeff ex. Secr fungus have been known to have biological activities, including antibacterial, antiviral, anticancer, antioxidant, anticomplementary and immunostimulating effects. In this study we first time identified that Agaricus silvaticus Schaeff ex. Secr has interferon like activity. We first time isolated the four known compounds such as, mannitol (1), urea (2), ergosterol (3) and ergosterol peroxide (4) from 95% ethanol extracts of Agaricus silvaticus Schaeff ex. Secr in Mongolia. Their structures were elucidated on the basis of extensive analysis of spectral data and by comparison with authentic samples.DOI: http://dx.doi.org/10.5564/mjc.v12i0.180 Mongolian Journal of Chemistry Vol.12 2011: 92-97
The mechanochemical activation study of Tsagaan-tsav zeolite
Authors: Zolzaya Ts , Davaabal B , Ochirbat Z , Oyun-Erdene G , Minjigmaa A , Temuujin J
Published: September 2014

Characterisation of mechanochemically activated Tsagaan-tsav zeolite has been performed. Tsagaan-tsav zeolite has been activated with a vibration mill for 2, 3, 5, 10 and 20 minutes. Ball to powder ratios were varied 1:10, 1:20, 1:50 and 1:100. Efficiency of milling determined based on amorphisation rate and cation exchange capacity changes. The highest efficiency was obtained for zeolite milled with ball to powder ratio of 100. Structural characterisation was performed with XRD, SEM, BET and particle size analyzer. Mechanochemical activation improves cation exchange capacity of natural zeolite.DOI: http://dx.doi.org/10.5564/mjc.v12i0.181 Mongolian Journal of Chemistry Vol.12 2011: 98-101
Physics-chemical study of hydration process of three calcium aluminate phase and Metakaolin
Authors: Erdenebat Ts , Sanjaasuren R
Published: September 2014

This research based on X-Ray Diffraction, SEM and chemical analyses were revealed that decreasing of Ca(OH)2 phase content and increasing of C3AH6 and trisulfate aluminate calcium-3 as the stable phases for the hydration period of first 30 to 60 minutes when comparing K-crent doping to the phase to without any doping. Also results have been proposed in case of doping metakaoline to draw structural analogies as formation of stable hydrated phases and the decrease of new formed unstable crystalline metaphases in the early stage of 3CAO·Al2O3 hydration process.DOI: http://dx.doi.org/10.5564/mjc.v12i0.183 Mongolian Journal of Chemistry Vol.12 2011: 107-112
Effects of long-term reduced tillage on weed infestation of pea (Pisum sativum L.)
Authors: Woźniak Andrzej , Soroka Myroslawa
Published: September 2014

The study evaluated weed infestation of pea (Pisum sativum L.) cultivated under conditions of conventional (CT), reduced (RT) and herbicide tillage (HT). It demonstrated the highest weed density per m2 in plots with the herbicide (HT) and reduced (RT) systems and significantly lower weed infestation in plots cultivated in the conventional system (CT). In addition, more weeds occurred at the third leaf stage (13/14 in BBCH scale) than at the pod development stage (73/74 BBCH) of pea. The highest biomass was produced by weeds in the herbicide system (HT), a lower one – in the reduced system (RT), and the lowest one – in the conventional system (CT). The air-dry weight of weeds depended also on pea development stage. At the pod development stage (73/74 BBCH), the air-dry weight of weeds was significantly higher than at the third leaf stage (13/14 BBCH). The tillage system was also observed to influence the species composition of weeds. This trait was also affected by the period of weed infestation assessment. At the third leaf stage of pea (13/14 BBCH), there occurred 26 weed species, including 24 annual ones. The most abundant species included: Chenopodium album L., Stellaria media (L.) Vill., Capsella bursa-pastoris (L.) Med., Matricaria inodora L., Thlaspi arvense L., and Fallopia convolvulus (L.) A. Löve. At the pod development stage (73/74 BBCH), the pea crop was colonized by 24 weed species, including 3 perennial ones. At this stage the predominant species included: Avena fatua L., Amaranthus retroflexus L., Papaver rhoeas L., Echinochloa crus-galli (L.) P.B., Matricaria inodora L., and Galeopsis tetrahit L.
Neuropsychological Phenotype in Wolf-Hirschhorn Syndrome
Authors: Cossu Maria Cristina , Albergo Annalisa , Galluzzi Claudia , Stefani Cristiana , Antonucci Gabriella
Published: September 2014

The Wolf-Hirschhorn syndrome (WHS) is a rare genetic disorder that causes a range of intellectual disability from mild to severe. In this study, we used standard tools to psychometrically characterize the specific neuropsychological phenotype of WHS. We studied 57 individuals with WHS, ranging in age from 2.6 to 28.6 years representing 70% of the certified Italian WHS population. Results obtained by administering Griffiths’ Mental Developmental Scales and the Vineland Adaptive Behavior Scale revealed a typical WHS neuropsychological phenotype characterized by specific strengths and weaknesses. Despite their severe cognitive impairment, in both scales, patients showed better communication and social interaction skills compared to visuo-motor abilities.
Results of our study could bring to the development of new and more effective treatments for individuals affected by WHS: based on neuropsychological phenotype description, it should be possible to design specific rehabilitation programs. These programs would then be aimed at improving rehabilitation protocols to optimize the developmental potential and personal independence of individuals with WHS and thus to improve their quality of life.
Preterm Infants’ Follow-Up Program at a Public Hospital in Buenos Aires: Two-Decade Study
Authors: Aspres N. , Schapira I. , Benitez A. , Galindo A. , Brundi M. , Kasten L. , Feld V. , Granovsky G. , Allignani G. , Fiorentino A. , Cuneo-Libarona M. , Vivas S. , Gerometta G. , Gonzalez M. A. , Gardiol A.B. Álvarez
Published: September 2014

Objectives: To analyze temporal trends of mortality, morbidity, growth and neurodevelopment until 2 years of corrected age (CA) of very low birth weight infants (VLBWI) born between 1986- 2005 in Ramon Sardá Maternal Infant Hospital (RSMIH).
Methods: Descriptive temporal trend study divided in 5 quinquenniums. 1255 VLBWI were born at RSMIH between 1986-2005; 46 were excluded (genetic syndromes, major congenital malformations, confirmed intrauterine infections), 84 were referred out and 1125 were studied. Birth weight (BW), gestational age (GA); morbidity; growth; neurodevelopment at 1 and 2 years of CA; neurological and sensorial disorders, antenatal steroids use, breastfeeding; rehospitalizations; mothers´ age and years of schooling and Unsatisfied Basic Needs Index (UBNI) were recorded.
Results: Survival rates increased during the last two periods, especially in <1000g BW infants despite the decrease in GA and BW. Children receiving surfactant (Sf), parenteral nutrition (PN) and antenatal steroids (AS) in the last quinquennium obtained better results in growth (40 weeks GA and 1 CA). The use of these therapies increased greatly in the last decade. Also breastfeeding at 40 weeks GA and 4 months tended to be better. Bronchopulmonary dysplasia (BPD) increased. Rehospitalizations (majorly attributable to lower tract infections) and UBNI stayed equal all along. Mothers’ years of schooling increased a little in the last two quinquenniums.
Conclusion: In the last quinquennium children tended to be smaller in GA and BW due to an increase in the survival rate as a result of higher technology and appropriate interventions such as AS, PN, Sf, etc.
Sensitivity of power functions to aggregation: Bias and uncertainty in radar rainfall retrieval
Authors: Sassi M. G. , Leijnse H. , Uijlenhoet R.
Published: September 2014

Rainfall retrieval using weather radar relies on power functions between radar reflectivity Z and rain rate R. The nonlinear nature of these relations complicates the comparison of rainfall estimates employing reflectivities measured at different scales. Transforming Z into R using relations that have been derived for other scales results in a bias and added uncertainty. We investigate the sensitivity of Z‐R relations to spatial and temporal aggregation using high‐resolution reflectivity fields for five rainfall events. Existing Z‐R relations were employed to investigate the behavior of aggregated Z‐R relations with scale, the aggregation bias, and the variability of the estimated rain rate. The prefactor and the exponent of aggregated Z‐R relations systematically diverge with scale, showing a break that is event‐dependent in the temporal domain and nearly constant in space. The systematic error associated with the aggregation bias at a given scale can become of the same order as the corresponding random error associated with intermittent sampling. The bias can be constrained by including information about the variability of Z within a certain scale of aggregation, and is largely captured by simple functions of the coefficient of variation of Z. Several descriptors of spatial and temporal variability of the reflectivity field are presented, to establish the links between variability descriptors and resulting aggregation bias. Prefactors in Z‐R relations can be related to multifractal properties of the rainfall field. We find evidence of scaling breaks in the structural analysis of spatial rainfall with aggregation.
Howard Receives 2013 G. K. Gilbert Award: Citation
Authors: Dietrich William E.
Published: September 2014

Alan Howard is the recipient of the 2013 Earth and Planetary Surface Processes focus group's G. K. Gilbert Award.
Nittrouer Receives 2013 Luna B. Leopold Young Scientist Award: Citation
Authors: Parker Gary
Published: September 2014

Jeffrey Nittrouer has earned the 2013 Luna B. Leopold Award based on his research related to the most significant new discovery in fluvial morphology since the turn of the century, that is, for the identification of the lower Mississippi River as a mixed bedrock‐alluvial stream, for his thorough quantification and elucidation of the dynamics of sand flow through it, and for his contributions to the use of Mississippi River sand as a tool for restoring lost land in the Mississippi delta wetlands.
Nittrouer Receives 2013 Luna B. Leopold Young Scientist Award: Response
Authors: Nittrouer Jeffrey A.
Published: September 2014

I am grateful for receiving the Luna B. Leopold Award from the Earth and Planetary Surface Processes (EPSP) focus group at AGU. I am thankful to the mentors and colleagues who played important roles in shaping my science over the past 10 years. Significant credit goes to three people in particular: David Mohrig, Gary Parker, and Mead Allison. These gentlemen patiently developed and honed my skills for observing, modeling, and theorizing about the physical processes that produce fluvial‐deltaic morphology and stratigraphy. It was an incredible opportunity to have worked with such a diverse set of thinkers, who regularly pushed me to consider and pursue new ideas, preventing too much comfort with the scientific status quo. Their mentoring fostered an independent and creative focus that produced the science for which this award has been generously given.
What drives migration of riverbed sand dunes?
Authors: Schultz Colin
Published: September 2014

Depending on grain size, river sediments fall into two main groups: wash load (grains that never fall out of suspension) and bed load (sediment that rests on the riverbed). Bed load sediment, similarly, can be either resting on the riverbed or temporarily in suspension, at which point it is known as suspended load.
Observing thermomagnetic stability of nonideal magnetite particles: Good paleomagnetic recorders?
Authors: Almeida Trevor P. , Kasama Takeshi , Muxworthy Adrian R. , Williams Wyn , Nagy Lesleis , Dunin‐Borkowski Rafal E.
Published: September 2014

The thermomagnetic behavior of remanence‐induced magnetite (Fe3O4) particles in the pseudo‐single‐domain (PSD) size range (~0.1–10 µm), which dominate the magnetic signature of many rock lithologies, is investigated using off‐axis electron holography. Construction of magnetic induction maps allowed for the visualization of the vortex domain state in an individual Fe3O4 grain (~200 nm in diameter) as a function of temperature. Acquisition of a series of electron holograms at 100°C intervals during in situ heating up to 700°C demonstrates the vortex state of the Fe3O4 grain, in this instance, remains thermally stable close to its unblocking temperature and exhibits a similar in‐plane remanent state upon cooling; i.e., the particle is effectively behaving like a uniaxial single‐domain particle to temperatures near TC. Such particles are thought to be robust magnetic recorders. It is suggested that evidence for PSD behavior should therefore not preclude paleomagnetic investigation.
Cyclone‐cyclone interactions through the ocean pathway
Authors: Balaguru Karthik , Taraphdar Sourav , Leung L. Ruby , Foltz Gregory R. , Knaff John A.
Published: September 2014

The intense sea surface temperature cooling caused by tropical cyclone‐induced mixing lasts several weeks and may thus influence a later cyclone passing over it. Using a 28 year analysis spanning the North Atlantic, eastern Pacific, and Northwest Pacific, we systematically demonstrate that, on average, when tropical cyclones encounter lingering wakes, they experience sea surface temperatures that are ∼0.25–0.5°C colder. Consequently, the intensification rates are lower for cyclones when they interact with wakes, consistent with the maximum potential intensity theory. The probability for cyclones to encounter lingering wakes varies positively with cyclone frequency, is ∼10% on average, and has been as high as 27%–37% in the past. These large interaction probabilities reduce the mean intensification rates for cyclones by 3%–6% on average and by ∼12%–15% during the most active years. “Cyclone‐cyclone interactions” may therefore represent a mechanism through which tropical cyclones self‐regulate their activity to an extent on intraseasonal time scales.
Dynamic weakening of serpentinite gouges and bare surfaces at seismic slip rates
Authors: Proctor B. P. , Mitchell T. M. , Hirth G. , Goldsby D. , Zorzi F. , Platt J. D. , Di Toro G.
Published: September 2014

To investigate differences in the frictional behavior between initially bare rock surfaces of serpentinite and powdered serpentinite (“gouge”) at subseismic to seismic slip rates, we conducted single‐velocity step and multiple‐velocity step friction experiments on an antigorite‐rich and lizardite‐rich serpentinite at slip rates (V) from 0.003 m/s to 6.5 m/s, sliding displacements up to 1.6 m, and normal stresses (σn) up to 22 MPa for gouge and 97 MPa for bare surfaces. Nominal steady state friction values (μnss) in gouge at V = 1 m/s are larger than in bare surfaces for all σn tested and demonstrate a strong σn dependence; μnss decreased from 0.51 at 4.0 MPa to 0.39 at 22.4 MPa. Conversely, μnss values for bare surfaces remained ~0.1 with increasing σn and V. Additionally, the velocity at the onset of frictional weakening and the amount of slip prior to weakening were orders of magnitude larger in gouge than in bare surfaces. Extrapolation of the normal stress dependence for μnss suggests that the behavior of antigorite gouge approaches that of bare surfaces at σn ≥ 60 MPa. X‐ray diffraction revealed dehydration reaction products in samples that frictionally weakened. Microstructural analysis revealed highly localized slip zones with melt‐like textures in some cases gouge experiments and in all bare surfaces experiments for V ≥ 1 m/s. One‐dimensional thermal modeling indicates that flash heating causes frictional weakening in both bare surfaces and gouge. Friction values for gouge decrease at higher velocities and after longer displacements than bare surfaces because strain is more distributed.