bluuebunny/crossref_metadata_2025 huggingface dataset:
Genetic variability within and among Haemonchus contortus isolates from goats and sheep in China
Authors: Yin Fanyuan , Gasser Robin B , Li Facai , Bao Min , Huang Weiyi , Zou Fengcai , Zhao Guanghui , Wang Chunren , Yang Xin , Zhou Yanqin , Zhao Junlong , Fang Rui , Hu Min
Published: September 2013

Background

Haemonchus contortus (order Strongylida) is a common parasitic nematode infecting small ruminants and causing significant economic losses worldwide. Knowledge of genetic variation within and among H. contortus populations can provide a foundation for understanding transmission patterns, the spread of drug resistance alleles and might assist in the control of haemonchosis.

Methods

152 H. contortus individual adult worms were collected from seven different geographical regions in China. The second internal transcribed spacer (ITS-2) of the nuclear ribosomal DNA and mitochondrial nicotinamide dehydrogenase subunit 4 gene (nad 4) were amplified by polymerase chain reaction (PCR) and sequenced directly. The sequence variations and population genetic diversities were determined.

Results

Nucleotide sequence analyses revealed 18 genotypes (ITS-2) and 142 haplotypes (nad 4) among the 152 worms, with nucleotide diversities of 2.6% and 0.027, respectively, consistent with previous reports from other countries, including Australia, Brazil, Germany, Italy, Malaysia, Sweden, the USA and Yemen. Population genetic analyses revealed that 92.4% of nucleotide variation was partitioned within populations; there was no genetic differentiation but a high gene flow among Chinese populations; some degree of genetic differentiation was inferred between some specimens from China and those from other countries.

Conclusions

This is the first study of genetic variation within H. contortus in China. The results revealed high within-population variations, low genetic differentiation and high gene flow among different populations of H. contortus in China. The present results could have implications for studying the epidemiology and ecology of H. contortus in China.
Ciliogenesis and cerebrospinal fluid flow in the developing Xenopus brain are regulated by foxj1
Authors: Hagenlocher Cathrin , Walentek Peter , Müller Christina , Thumberger Thomas , Feistel Kerstin
Published: September 2013

Background

Circulation of cerebrospinal fluid (CSF) through the ventricular system is driven by motile cilia on ependymal cells of the brain. Disturbed ciliary motility induces the formation of hydrocephalus, a pathological accumulation of CSF resulting in ventricle dilatation and increased intracranial pressure. The mechanism by which loss of motile cilia causes hydrocephalus has not been elucidated. The aim of this study was: (1) to provide a detailed account of the development of ciliation in the brain of the African clawed frog Xenopus laevis; and (2) to analyze the relevance of ependymal cilia motility for CSF circulation and brain ventricle morphogenesis in Xenopus.

Methods

Gene expression analysis of foxj1, the bona fide marker for motile cilia, was used to identify potentially ciliated regions in the developing central nervous system (CNS) of the tadpole. Scanning electron microscopy (SEM) was used to reveal the distribution of mono- and multiciliated cells during successive stages of brain morphogenesis, which was functionally assessed by bead injection and video microscopy of ventricular CSF flow. An antisense morpholino oligonucleotide (MO)-mediated gene knock-down that targeted foxj1 in the CNS was applied to assess the role of motile cilia in the ventricles.

Results

RNA transcripts of foxj1 in the CNS were found from neurula stages onwards. Following neural tube closure, foxj1 expression was seen in distinct ventricular regions such as the zona limitans intrathalamica (ZLI), subcommissural organ (SCO), floor plate, choroid plexus (CP), and rhombomere boundaries. In all areas, expression of foxj1 preceded the outgrowth of monocilia and the subsequent switch to multiciliated ependymal cells. Cilia were absent in foxj1 morphants, causing impaired CSF flow and fourth ventricle hydrocephalus in tadpole-stage embryos.

Conclusions

Motile ependymal cilia are important organelles in the Xenopus CNS, as they are essential for the circulation of CSF and maintenance of homeostatic fluid pressure. The Xenopus CNS ventricles might serve as a novel model system for the analysis of human ciliary genes whose deficiency cause hydrocephalus.
Radiofluorination and biological evaluation of N-aryl-oxadiazolyl-propionamides as potential radioligands for PET imaging of cannabinoid CB2 receptors
Authors: Teodoro Rodrigo , Moldovan Rareş-Petru , Lueg Corinna , Günther Robert , Donat Cornelius K , Ludwig Friedrich-Alexander , Fischer Steffen , Deuther-Conrad Winnie , Wünsch Bernhard , Brust Peter
Published: September 2013

Background

The level of expression of cannabinoid receptor type 2 (CB2R) in healthy and diseased brain has not been fully elucidated. Therefore, there is a growing interest to assess the regional expression of CB2R in the brain. Positron emission tomography (PET) is an imaging technique, which allows quantitative monitoring of very low amounts of radiolabelled compounds in living organisms at high temporal and spatial resolution and, thus, has been widely used as a diagnostic tool in nuclear medicine. Here, we report on the radiofluorination ofN-aryl-oxadiazolyl-propionamides at two different positions in the lead structure and on the biological evaluation of the potential of the two tracers [18F]1and [18F]2as CB2receptor PET imaging agents.

Results

High binding affinity and specificity towards CB2receptors of the lead structure remained unaffected by the structural changes such as the insertion of the aliphatic and aromatic fluorine in the selected labelling sites of1and2. Aliphatic and aromatic radiofluorinations were optimized, and [18F]1and [18F]2were achieved in radiochemical yields of ≥30% with radiochemical purities of ≥98% and specific activities of 250 to 450 GBq/μmol. Organ distribution studies in female CD1 mice revealed that both radiotracers cross the blood–brain barrier (BBB) but undergo strong peripheral metabolism. At 30 min after injection, unmetabolized [18F]1and [18F]2accounted for 60% and 2% as well as 68% and 88% of the total activity in the plasma and brain, respectively. The main radiometabolite of [18F]2could be identified as the free acid [18F]10, which has no affinity towards the CB1and CB2receptors but can cross the BBB.

Conclusions

N-aryl-oxadiazolyl-propionamides can successfully be radiolabelled with18F at different positions. Fluorine substitution at these positions did not affect affinity and specificity towards CB2R. Despite a promisingin vitrobehavior, a rather rapid peripheral metabolism of [18F]1and [18F]2in mice and the generation of brain permeable radiometabolites hamper the application of these radiotracersin vivo. However, it is expected that future synthetic modification aiming at a replacement of metabolically susceptible structural elements of [18F]1and [18F]2will help to elucidate the potential of this class of compounds for CB2R PET studies.
Localization of premature ventricular contraction foci in normal individuals based on multichannel electrocardiogram signals processing
Authors: Soheilykhah Sima , Sheikhani Ali , Sharif Alireza Ghorbani , Daevaeiha Mohammad M
Published: September 2013

A premature ventricular contraction (PVC) is relatively a common event where the heartbeat is initiated by the other pathway rather than by the Sinoatrial node, the normal heartbeat initiator. Determining PVC foci is important for ablation procedure and it can help in pre-procedural planning and potentially may improve ablation outcome.

In this study, 12-lead Electrocardiogram (ECG) of 87 patients without structural cardiac diseases, who had experienced PVC, were obtained. Initially, PVC foci were labeled based on Electrophysiology study (EPS) reports. PVC beats were detected by wavelet method and their foci were classified using Mahalanobis distance and One-way ANOVA. Using morphological, frequency and spectrogram features, these foci in the heart were classified into five groups: Left Ventricular Outflow Tract (LVOT), Right Ventricular Outflow Tract (RVOT) septum, basal Right Ventricular (RV), RVOT free-wall, and Aortic Cusp (AC).

The results showed that 88.4% of patients are classified correctly.
PPARγ Activation Inhibits Growth and Survival of Human Endometriotic Cells by Suppressing Estrogen Biosynthesis and PGE2 Signaling.
Authors: Lebovic Dan I. , Kavoussi Shahryar K. , Lee JeHoon , Banu Sakhila K. , Arosh Joe A.
Published: September 2013

Endometriosis is a chronic inflammatory disease of reproductive age women leading to chronic pelvic pain and infertility. Current antiestrogen therapies are temporizing measures, and endometriosis often recurs. Potential nonestrogenic or nonsteroidal targets are needed for treating endometriosis. Peroxisome proliferator-activated receptor (PPAR)γ, a nuclear receptor, is activated by thiazolidinediones (TZDs). In experimental endometriosis, TZDs inhibit growth of endometriosis. Clinical data suggest potential use of TZDs for treating pain and fertility concurrently in endometriosis patients. Study objectives were to 1) determine the effects of PPARγ action on growth and survival of human endometriotic epithelial and stromal cells and 2) identify the underlying molecular links between PPARγ activation and cell cycle regulation, apoptosis, estrogen biosynthesis, and prostaglandin E2 biosynthesis and signaling in human endometriotic epithelial and stromal cells. Results indicate that activation of PPARγ by TZD ciglitazone 1) inhibits growth of endometriotic epithelial cells 12Z up to 35% and growth of endometriotic stromal cells 22B up to 70% through altered cell cycle regulation and intrinsic apoptosis, 2) decreases expression of PGE2 receptors (EP)2 and EP4 mRNAs in 12Z and 22B cells, and 3) inhibits expression and function of P450 aromatase mRNA and protein and estrone production in 12Z and 22B cells through EP2 and EP4 in a stromal-epithelial cell-specific manner. Collectively, these results indicate that PGE2 receptors EP2 and EP4 mediate actions of PPARγ by incorporating multiple cell signaling pathways. Activation of PPARγ combined with inhibition of EP2 and EP4 may emerge as novel nonsteroidal therapeutic targets for endometriosis-associated pain and infertility, if clinically proven safe and efficacious.
Nesfatin-1 in Human and Murine Cardiomyocytes: Synthesis, Secretion, and Mobilization of GLUT-4
Authors: Feijóo-Bandín Sandra , Rodríguez-Penas Diego , García-Rúa Vanessa , Mosquera-Leal Ana , Otero Manuel Francisco , Pereira Eva , Rubio José , Martínez Isabel , Seoane Luisa María , Gualillo Oreste , Calaza Manuel , García-Caballero Tomás , Portolés Manuel , Roselló-Lletí Esther , Diéguez Carlos , Rivera Miguel , González-Juanatey José Ramón , Lago Francisca
Published: September 2013

Nesfatin-1, a satiety-inducing peptide identified in hypothalamic regions that regulate energy balance, is an integral regulator of energy homeostasis and a putative glucose-dependent insulin coadjuvant. We investigated its production by human cardiomyocytes and its effects on glucose uptake, in the main cardiac glucose transporter GLUT-4 and in intracellular signaling. Quantitative RT-PCR, Western blots, confocal immunofluorescence microscopy, and ELISA of human and murine cardiomyocytes and/or cardiac tissue showed that cardiomyocytes can synthesize and secrete nesfatin-1. Confocal microscopy of cultured cardiomyocytes after GLUT-4 labeling showed that nesfatin-1 mobilizes this glucose transporter to cell peripherals. The rate of 2-deoxy-d-[3H]glucose incorporation demonstrated that nesfatin-1 induces glucose uptake by HL-1 cells and cultured cardiomyocytes. Nesfatin-1 induced dose- and time-dependent increases in the phosphorylation of ERK1/2, AKT, and AS160. In murine and human cardiac tissue, nesfatin-1 levels varied with diet and coronary health. In conclusion, human and murine cardiomyocytes can synthesize and secrete nesfatin-1, which is able to induce glucose uptake and the mobilization of the glucose transporter GLUT-4 in these cells. Nesfatin-1 cardiac levels are regulated by diet and coronary health.
Regulation of LH Receptor mRNA Binding Protein by miR-122 in Rat Ovaries
Authors: Menon Bindu , Sinden Jennifer , Franzo-Romain Meghan , Botta Raman Bhadradri , Menon K. M. J.
Published: September 2013

LH receptor (LHR) expression in the ovary is regulated by the RNA binding protein, (LHR mRNA binding protein [LRBP]), which has been identified as being mevalonate kinase. This study examined the role of microRNA miR-122 in LRBP-mediated LHR mRNA expression. Real-time PCR analysis of ovaries from pregnant mare serum gonadotropin/human chorionic gonadotropin (hCG)-primed female rats treated with hCG to down-regulate LHR expression showed that an increase in miR-122 expression preceded LHR mRNA down-regulation. The expression of miR-122 and its regulation was confirmed using fluorescent in situ hybridization of the frozen ovary sections using 5′-fluorescein isothiocyanate-labeled miR-122 locked nucleic acid probe. The increased expression of miR-122 preceded increased expression of LRBP mRNA and protein, and these increases were followed by LHR mRNA down-regulation. Inhibition of protein kinase A (PKA) and ERK1/2 signaling pathways by H89 and UO126, respectively, attenuated the hCG-mediated up-regulation of miR-122 levels. This was also confirmed in vitro using human granulosa cells. These results suggest the possibility that hCG-mediated miR-122 expression is mediated by the activation of cAMP/PKA/ERK signaling pathways. Inhibition of miR-122 by injection of the locked nucleic acid-conjugated antagomir of miR-122 abrogated the hCG-mediated increases in LRBP protein expression. Because it has been previously shown that miR-122 regulates sterol regulatory element-binding proteins (SREBPs) and SREBPs, in turn, regulate LRBP expression, the role of SREBPs in miR-122-mediated increase in LRBP expression was then examined. The levels of active forms of both SREBP-1a and SREBP-2 were increased in response to hCG treatment, and the stimulatory effect was sustained up to 4 hours. Taken together, our results suggest that hCG-induced down-regulation of LHR mRNA expression is mediated by activation of cAMP/PKA/ERK pathways to increase miR-122 expression, which then increases LRBP expression through the activation of SREBPs.
Genomic Basis of Aromatase Excess Syndrome: Recombination- and Replication-Mediated Rearrangements Leading to CYP19A1 Overexpression
Authors: Fukami Maki , Tsuchiya Takayoshi , Vollbach Heike , Brown Kristy A. , Abe Shuji , Ohtsu Shigeyuki , Wabitsch Martin , Burger Henry , Simpson Evan R. , Umezawa Akihiro , Shihara Daizou , Nakabayashi Kazuhiko , Bulun Serdar E. , Shozu Makio , Ogata Tsutomu
Published: September 2013

Context:

Genomic rearrangements at 15q21 have been shown to cause overexpression of CYP19A1 and resultant aromatase excess syndrome (AEXS). However, mutation spectrum, clinical consequences, and underlying mechanisms of these rearrangements remain to be elucidated.

Objective:

The aim of the study was to clarify such unsolved matters.

Design, Setting, and Methods:

We characterized six new rearrangements and investigated clinical outcome and local genomic environments of these rearrangements and of three previously reported duplications/deletions.

Results:

Novel rearrangements included simple duplication involving exons 1–10 of CYP19A1 and simple and complex rearrangements that presumably generated chimeric genes consisting of the coding region of CYP19A1 and promoter-associated exons of neighboring genes. Clinical severities were primarily determined by the copy number of CYP19A1 and the property of the fused promoters. Sequences at the fusion junctions suggested nonallelic homologous recombination, nonhomologous end-joining, and replication-based errors as the underlying mechanisms. The breakpoint-flanking regions were not enriched with GC content, palindromes, noncanonical DNA structures, or known rearrangement-associated motifs. The rearrangements resided in early-replicating segments.

Conclusions:

These results indicate that AEXS is caused by duplications involving CYP19A1 and simple and complex rearrangements that presumably lead to the usage of cryptic promoters of several neighboring genes. Our data support the notion that phenotypes depend on the dosage of CYP19A1 and the characteristics of the fused promoters. Furthermore, we show that the rearrangements in AEXS are generated by both recombination- and replication-mediated mechanisms, independent of the known rearrangement-inducing DNA features or late-replication timing. Thus, AEXS represents a unique model for human genomic disorders.
Environmental and hormonal factors controlling reversible colour change in crab spiders
Authors: Llandres Ana L. , Figon Florent , Christidès Jean-Philippe , Mandon Nicole , Casas Jérôme
Published: September 2013

Habitat heterogeneity that occurs within an individual's lifetime may favour the evolution of reversible plasticity. Colour reversibility has many different functions in animals, such as thermoregulation, crypsis through background matching and social interactions. However, the mechanisms underlying reversible colour changes are yet to be thoroughly investigated. This study aims to determine the environmental and hormonal factors underlying morphological colour changes in Thomisus onustus crab spiders and the biochemical metabolites produced during these changes. We quantified the dynamics of colour changes over time: spiders were kept in yellow and white containers under natural light conditions and their colour was measured over 15 days using a spectrophotometer. We also characterised the chemical metabolites of spiders changing to a yellow colour using HPLC. Hormonal control of colour change was investigated by injecting 20-hydroxyecdysone (20E) into spiders. We found that background colouration was a major environmental factor responsible for colour change in crab spiders: individuals presented with white and yellow backgrounds changed to white and yellow colours, respectively. An ommochrome precursor, 3-OH-kynurenine, was the main pigment responsible for yellow colour. Spiders injected with 20E displayed a similar rate of change towards yellow colouration as spiders kept in yellow containers and exposed to natural sunlight. This study demonstrates novel hormonal manipulations that are capable of inducing reversible colour change.
Nonshivering thermogenesis in the African lesser bushbaby,Galago moholi
Authors: Nowack Julia , Dausmann Kathrin H. , Mzilikazi Nomakwezi
Published: September 2013

The capacity for nonshivering thermogenesis (NST) plays an important role during arousal from torpid states. Recent data on heterotherms inhabiting warmer regions, however, suggest that passive rewarming reduces the need of metabolic heat production during arousal significantly, leading to the question: to what extent do subtropical or tropical heterotherms depend on NST? The African lesser bushbaby, Galago moholi, enters torpid states as an emergency response only, but otherwise stays normothermic throughout the cold and dry winter season. In addition, this species shows unusual rewarming difficulties during arousal from torpor on cold days. We therefore examined the seasonal adjustments of the capacity for NST of naturally acclimatized G. moholi by stimulation with noradrenaline (NA) injection. Dissection of two adult female bushbabies revealed that G. moholi possesses brown adipose tissue, and NA treatment (0.5 mg kg−1, s.c.) induced a significant elevation in oxygen consumption compared with control (saline) injection. However, the increase in oxygen consumption following injection of NA was not significantly different between winter and summer. Our results show that the ability to produce heat via NST seems to be available throughout the year and that G. moholi is able to change NST capacity within a very short time frame in response to cold spells. Together with results from studies on other (Afro-)tropical heterotherms, which also indicate low or even absent seasonal difference in NST capacity, this raises the question of whether the definition of NST needs to be refined for (Afro-)tropical mammals.
Deep mutational scanning of an RRM domain of the Saccharomyces cerevisiae poly(A)-binding protein
Authors: Melamed Daniel , Young David L. , Gamble Caitlin E. , Miller Christina R. , Fields Stanley
Published: September 2013

The RNA recognition motif (RRM) is the most common RNA-binding domain in eukaryotes. Differences in RRM sequences dictate, in part, both RNA and protein-binding specificities and affinities. We used a deep mutational scanning approach to study the sequence-function relationship of the RRM2 domain of the Saccharomyces cerevisiae poly(A)-binding protein (Pab1). By scoring the activity of more than 100,000 unique Pab1 variants, including 1246 with single amino acid substitutions, we delineated the mutational constraints on each residue. Clustering of residues with similar mutational patterns reveals three major classes, composed principally of RNA-binding residues, of hydrophobic core residues, and of the remaining residues. The first class also includes a highly conserved residue not involved in RNA binding, G150, which can be mutated to destabilize Pab1. A comparison of the mutational sensitivity of yeast Pab1 residues to their evolutionary conservation reveals that most residues tolerate more substitutions than are present in the natural sequences, although other residues that tolerate fewer substitutions may point to specialized functions in yeast. An analysis of ∼40,000 double mutants indicates a preference for a short distance between two mutations that display an epistatic interaction. As examples of interactions, the mutations N139T, N139S, and I157L suppress other mutations that interfere with RNA binding and protein stability. Overall, this study demonstrates that living cells can be subjected to a single assay to analyze hundreds of thousands of protein variants in parallel.
European Dimensions of Residential Tenancy LawThis contribution presents the cooperative project ‘Tenancy Law and Housing Policy in the EU’ (www.tenlaw.uni-bremen.de) under the EU’s Seventh Research Framework Programme, which is coordinated by the Centre of European Law and Politics (ZERP) at Bremen University. The consortium is further composed of the Universities Southampton, Pisa, Tarragona, Lund, Katowice, Tartu, Celje, Delft and the Metropolitan Research Institute Budapest. The opinions stated in this paper are personal.
Authors: Schmid Christoph U. , Dinse Jason R.
Published: September 2013

Although one third of European citizens depend on rental housing, its legal regulation in residential tenancy law constitutes a nearly blank space in comparative and European Union law. This is due to its national character, its perceived political nature and its embeddedness in widely diverging national housing policies. At the same time, however, EU law and policies from other fields do affect tenancy law significantly, albeit indirectly and with little visibility. The present contribution tries in a first step to take stock of these influences, which range from social policy, competition law, consumer and contract law, conflict of laws, anti-discrimination and environmental law to the European Convention of Human Rights. On this basis, the potential for a European contribution to the field is examined in a second step. As regards European instruments, this contribution advises against legal harmonisation but recommends the extension of the existing open method of coordination mechanism in social policy to tenancy law. At the substantive level, a legal principle of ‘socio-economic balance’ is sketched out. This means that national legislators, regulators and judges should design viable compromise solutions taking into account party interests as well as macroeconomic and social criteria.
Brackish Water Desalination by Electrodialysis: CaCO3 Scaling Monitoring During Batch Recirculation Operation
Authors: Salah Sayadi Ilhem Ben , Sistat Philippe , Ben Amor Mohamed , Tlili Mohamed
Published: September 2013

The composition of feed water used in electrodialysis (ED) desalination causes the risk of CaCO3 scale crystallization in ED equipments, which leads to the decrease of process efficiency. To control scaling in water systems, several scaling indices and tests, permitting to predict the scaling occurrence, have been devised. In this study, an accelerated scaling test allowing to follow CaCO3 formation in water desalination plant using ED process was proposed. Tests were performed using a pilot unit as a conventional ED in batch recirculation mode. By simple in situ measurements of pH and flow rate of the concentrate, the crystallization onset and growth of CaCO3 were followed during the pilot operation. This leads to precise determination of the number of concentrate recirculation times and therefore to the highest recovery rate without scaling risk as a function of the inlet water quality and the antiscale pretreatment.
A Statistical Survey of the UK Residential Sector Electrical Loads
Authors: Tsagarakis George , Collin Adam , Kiprakis Aristides
Published: September 2013

This article presents a comprehensive statistical analysis of data obtained from a wide range of literature on the most widely used appliances in the UK residential load sector, as well as a comprehensive technology and market survey conducted by the authors. The article focuses on the individual appliances and begins by consideration of the electrical operations performed by the load. This approach allows for the loads to be categorised based on the electrical characteristics, which is particularly important for implementing load-use statistics in power system analysis. In addition to this, device ownership statistics and probability density functions of power demand are presented for the main residential loads. Although the data presented is primarily intended as a resource for the development of load profiles for power system analysis, it contains a large volume of information that provides a useful database for the wider research community.
Volunteer Participation and the Development of Civil Society in China: A Case Study of Jinan
Authors: Xu Ying
Published: September 2013

Spontaneous volunteer participation has developed rapidly over the past decade, though compulsory volunteer participation through top-to-bottom, government-based organizations is still prevalent among Chinese citizens. Drawing on a case study of Jinan, a city in China, this study explores the types of and motives for volunteer participation including how volunteers differ in their voluntary service experiences and what their attitudes are toward volunteering and the future development of civil society in China. The findings illustrate: first, spontaneous participants with rewarding experiences who volunteer through grassroots, issue-based VSOs are most likely to have a positive attitude toward volunteering and believe that volunteering can make contributions to the development of civil society. Second, participants in grassroots and community-based VSOs are most likely to have an enthusiastic attitude toward volunteering, but they tend to be indifferent about the idea of civil society. However, they tend to contribute to the development of volunteering and civil society when given the opportunity, because participation in voluntary services enhances their participatory abilities and their sense of self-organization and mutual collaboration. Last but not least, volunteers who participate in a poorly managed volunteering organization and have a dissatisfactory, non-rewarding volunteering experience are most likely to have a pessimistic attitude toward volunteering and civil society. The implications of volunteering for the development of civil society are also discussed.
Ceramic-polytetrafluoroethylene composite material-based miniaturized split-ring patch antenna
Authors: Ullah M. Habib , Islam Mohammad T. , Mandeep J.S. , Misran N.
Published: September 2013

A ceramic-polytetrafluoroethylene high-permittivity dielectric material-based split-ring patch antenna of dimensions 12 mm×16 mm is presented in this paper. The measured operating bandwidths (reflection coefficient <-10 dB) range from 5.0 to 6.5 GHz (1.5 GHz), 9.1 to 9.6 GHz (500 MHz), and 10.7 to 11 GHz (300 MHz) as observed from the proposed antennas. Average gains of 0.69, 3.52, and 3.48 dBi were measured at the first, second, and third band, respectively. Radiation efficiencies of 87.3%, 88.5%, and 93.1% were achieved at three resonant frequencies 5.6, 9.5, and 10.9 GHz, respectively. The measured symmetric and nearly consistent radiation pattern makes the proposed antenna suitable for C band and X band applications. In this paper, the effects of the dielectric properties of substrate material and design parameters have been studied.
Fast Vesicle Transport Is Required for the Slow Axonal Transport of Synapsin
Authors: Tang Yong , Scott David , Das Utpal , Gitler Daniel , Ganguly Archan , Roy Subhojit
Published: September 2013

Although it is known that cytosolic/soluble proteins synthesized in cell bodies are transported at much lower overall velocities than vesicles in fast axonal transport, the fundamental basis for this slow movement is unknown. Recently, we found that cytosolic proteins in axons of mouse cultured neurons are conveyed in a manner that superficially resembles diffusion, but with a slow anterograde bias that is energy- and motor-dependent (Scott et al., 2011). Here we show that slow axonal transport of synapsin, a prototypical member of this rate class, is dependent upon fast vesicle transport. Despite the distinct overall dynamics of slow and fast transport, experimentally induced and intrinsic variations in vesicle transport have analogous effects on slow transport of synapsin as well. Dynamic cotransport of vesicles and synapsin particles is also seen in axons, consistent with a model where higher-order assemblies of synapsin are conveyed by transient and probabilistic associations with vesicles moving in fast axonal transport. We posit that such dynamic associations generate the slow overall anterogradely biased flow of the population (“dynamic-recruitment model”). Our studies uncover the underlying kinetic basis for a classic cytosolic/soluble protein moving in slow axonal transport and reveal previously unknown links between slow and fast transport, offering a clearer conceptual picture of this curious phenomenon.
DHHC8-Dependent PICK1 Palmitoylation is Required for Induction of Cerebellar Long-Term Synaptic Depression
Authors: Thomas Gareth M. , Hayashi Takashi , Huganir Richard L. , Linden David J.
Published: September 2013

The palmitoyl acyltransferase (PAT) DHHC8 is implicated in synaptic regulation but few DHHC8 substrates are known. Here we report that DHHC8 binds and palmitoylates the PDZ domain-containing protein PICK1 at a cysteine residue that is essential for long-term synaptic depression (LTD) in cultured mouse cerebellar Purkinje neurons. Cerebellar LTD is palmitoylation-dependent and induction of LTD requires DHHC8. Furthermore, PICK1 is a critical DHHC8 substrate whose palmitoylation is necessary for LTD. These results identify the first DHHC8 substrate required for a specific form of synaptic plasticity and provide new insights into synaptic roles of palmitoylation.
Dab1 Is Required for Synaptic Plasticity and Associative Learning
Authors: Trotter Justin , Lee Gum Hwa , Kazdoba Tatiana M. , Crowell Beth , Domogauer Jason , Mahoney Heather M. , Franco Santos J. , Müller Ulrich , Weeber Edwin J. , D'Arcangelo Gabriella
Published: September 2013

Disabled-1 (Dab1) is an adaptor protein that is an obligate effector of the Reelin signaling pathway, and is critical for neuronal migration and dendrite outgrowth during development. Components of the Reelin pathway are highly expressed during development, but also continue to be expressed in the adult brain. Here we investigated in detail the expression pattern of Dab1 in the postnatal and adult forebrain, and determined that it is expressed in excitatory as well as inhibitory neurons. Dab1 was found to be localized in different cellular compartments, including the soma, dendrites, presynaptic and postsynaptic structures. Mice that are deficient in Dab1, Reelin, or the Reelin receptors ApoER2 and VLDLR exhibit severely perturbed brain cytoarchitecture, limiting the utility of these mice for investigating the role of this signaling pathway in the adult brain. In this study, we developed an adult forebrain-specific and excitatory neuron-specific conditional knock-out mouse line, and demonstrated that Dab1 is a critical regulator of synaptic function and hippocampal-dependent associative and spatial learning. These dramatic abnormalities were accompanied by a reduction in dendritic spine size, and defects in basal and plasticity-induced Akt and ERK1/2 signaling. Deletion of Dab1 led to no obvious changes in neuronal positioning, dendrite morphology, spine density, or synaptic composition. Collectively, these data conclusively demonstrate an important role for Reelin-Dab1 signaling in the adult forebrain, and underscore the importance of this pathway in learning and memory.
Short Hairpin RNA against PTEN Enhances Regenerative Growth of Corticospinal Tract Axons after Spinal Cord Injury
Authors: Zukor Katherine , Belin Stephane , Wang Chen , Keelan Nadia , Wang Xuhua , He Zhigang
Published: September 2013

Developing approaches to promote the regeneration of descending supraspinal axons represents an ideal strategy for rebuilding neuronal circuits to improve functional recovery after spinal cord injury (SCI). Our previous studies demonstrated that genetic deletion ofphosphatase and tensin homolog (PTEN)in mouse corticospinal neurons reactivates their regenerative capacity, resulting in significant regeneration of corticospinal tract (CST) axons after SCI. However, it is unknown whether nongenetic methods of suppressing PTEN have similar effects and how regenerating axons interact with the extrinsic environment. Herein, we show that suppressing PTEN expression with short-hairpin RNA (shRNA) promotes the regeneration of injured CST axons, and these axons form anatomical synapses in appropriate areas of the cord caudal to the lesion. Importantly, this model of increased CST regrowth enables the analysis of extrinsic regulators of CST regenerationin vivo. We find that regenerating axons avoid dense clusters of fibroblasts and macrophages in the lesion, suggesting that these cell types might be key inhibitors of axon regeneration. Furthermore, most regenerating axons cross the lesion in association with astrocytes, indicating that these cells might be important for providing a permissive bridge for axon regeneration. Lineage analysis reveals that these bridge-forming astrocytes are not derived from ependymal stem cells within the spinal cord, suggesting that they are more likely derived from a subset of mature astrocytes. Overall, this study reveals insights into the critical extrinsic and intrinsic regulators of axon regeneration and establishes shRNA as a viable means to manipulate these regulators and translate findings into other mammalian models.
GABAAReceptor Agonist and Antagonist Alter Vestibular Compensation and Different Steps of Reactive Neurogenesis in Deafferented Vestibular Nuclei of Adult Cats
Authors: Dutheil Sophie , Escoffier Guy , Gharbi Ali , Watabe Isabelle , Tighilet Brahim
Published: September 2013

Strong reactive cell proliferation occurs in the vestibular nuclei after unilateral vestibular neurectomy (UVN). Most of the newborn cells survive, differentiate into glial cells and neurons with GABAergic phenotype, and have been reported to contribute to recovery of the posturo-locomotor functions in adult cats. Because the GABAergic system modulates vestibular function recovery and the different steps of neurogenesis in mammals, we aimed to examine in our UVN animal model the effect of chronic infusion of GABAAreceptor (R) agonist and antagonist in the vestibular nuclei. After UVN and one-month intracerebroventricular infusions of saline, GABAAR agonist (muscimol) or antagonist (gabazine), cell proliferation and differentiation into astrocytes, microglial cells, and neurons were revealed using immunohistochemical methods. We also determined the effects of these drug infusions on the recovery of posturo-locomotor and oculomotor functions through behavioral tests. Our results showed that surprisingly, one month after UVN, newborn cells did not survive in the UVN-muscimol group whereas the number of GABAergic pre-existent neurons increased, and the long-term behavioral recovery of the animals was drastically impaired. Conversely, a significant number of newborn cells survived up to 1 month in the UVN-gabazine group whereas the astroglial population increased, and these animals showed the fastest recovery in behavioral functions. This study reports for the first time that GABA plays multiple roles, ranging from beneficial to detrimental on the different steps of a functional postlesion neurogenesis and further, strongly influences the time course of vestibular function recovery.
Slavic clitics: a typology
Authors: Zimmerling Anton , Kosta Peter
Published: September 2013

The paper offers a description of Slavic word order systems from the viewpoint of formal typology based on notions such as syntactic type, parametric settings, basic and derived order, linearization constraints, constituency, movement, spell-out, cliticity, clitic clusters, syntax-prosody interface, and grammaticalization.The aim is to classify Slavic word order systems with clitics on the basis of syntactic constraints without dependence on hypotheses about language-specific properties of prosodically deficient elements and to provide a viable typological classification, which can be verified by data from other world’s languages.
Deep subsoiling of a subsurface-compacted typical hapludult under citrus orchard
Authors: Medeiros João Carlos , Figueiredo Getulio Coutinho , Mafra Álvaro Luiz , Rosa Jaqueline Dalla , Yoon Sung Won
Published: September 2013

Soil management practices which increase the root depth penetration of citrus are important to the longevity and yield maintenance of this plant, especially in regions where long periods of drought are common, even in soil conventionally subsoiled to a depth of 30-40 cm, when the orchard was first established. The objective of this study was to evaluate the efficiency of subsoiling on the physical and hydric properties of a Typical Hapludult and fruit yield in a 14-year-old citrus orchard located in Piracicaba, SP. The treatments consisted of: no-subsoiling (with no tilling of the soil after the orchard was planted); subsoiling on one side of the plant lines (SUB. 1); and subsoiling on both sides of the plant lines (SUB. 2). The subsoiling treatments were carried out 1.5 m from the plant lines and to a depth of 0.8 m. Soil samples were taken 120 days after this operation, at four depths, in order to determine physical and hydric properties. Fruit yield was evaluated 150 days after subsoiling. Subsoiling between the plant lines of an old established citrus orchard alters the physical and hydric properties of the soil, which is reflected in increased soil macroporosity and unsaturated hydraulic conductivity, and reduced soil bulk density, critical degree-of-compactness and penetration resistance. The improvements in the physical and hydric properties of the soil were related to an increase in fruit number and orchard yield.
Análise de sensibilidade dos parâmetros do modelo SWAT e simulação dos processos hidrossedimentológicos em uma bacia no agreste nordestino
Authors: Aragão Ricardo de , Cruz Marcus Aurélio Soares , Amorim Julio Roberto Araujo de , Mendonça Luciana Coêlho , Figueiredo Eduardo Eneas de , Srinivasan Vajapeyam S.
Published: September 2013

O processo erosivo constitui-se na principal causa de degradação dos solos e é acelerado por intervenções humanas nas bacias hidrográficas, resultando em prejuízos ao setor agrícola e ao meio ambiente. Para a previsão dos impactos de ações antrópicas ou de mudanças climáticas sobre os processos hidrossedimentológicos, os modelos distribuídos e de base física têm sido bastante eficazes. Neste estudo, aplicou-se o modelo SWAT à sub-bacia do Rio Japaratuba Mirim, em Sergipe, nas seções de medição das estações Fazenda Pão de Açúcar (PA) e Fazenda Cajueiro (CJ), com áreas de contribuição respectivamente de 137,3 e 277,8 km², visando à parametrização das duas bacias aninhadas por meio dos processos de calibração e de validação. Foram realizadas simulações do escoamento na bacia menor (PA), a partir dos parâmetros calibrados na bacia maior (CJ), e, reciprocamente, do escoamento na bacia maior (CJ). Em seguida, foram também realizadas simulações do escoamento e da produção de sedimentos para o período de dados de vazão disponíveis (1985 a 2000), para a seção CJ. Os resultados evidenciaram que o modelo calibrado simulou bem o escoamento superficial e conseguiu prever, de forma coerente, a produção de sedimentos com base nos 12 parâmetros mais sensíveis do modelo. A transposição dos parâmetros da bacia maior para a menor e, vice-versa, resultou em índices de Eficiência de Nash-Sutcliffe (NSE) e de Tendência Percentual (PBIAS), considerados satisfatórios para o primeiro caso e insatisfatório para o segundo.
A arquitetura escolar como objeto de pesquisa em História da Educação
Authors: Dórea Célia Rosângela Dantas
Published: September 2013

Uma das ideias norteadoras desta pesquisa consiste em encarar a organização do espaço na escola como um dos movimentos que permitem recuperar a história dos estabelecimentos de ensino, possibilitando uma nova leitura dessa ambiência escolar, leitura em que se procura identificar os fatores - políticos, sociais, culturais e econômicos - que interferem na formulação e na execução das políticas educacionais que deram origem aos atuais espaços escolares. No rastro de uma trajetória acadêmica marcada pela intimidade com as questões relacionadas ao espaço escolar, discute-se o papel da organização do espaço na história da escola, destacando a atuação do educador Anísio Teixeira, em três momentos distintos, onde teve a oportunidade de implementar reformas e medidas educacionais que valorizavam o planejamento das edificações escolares: na Bahia (1924-1928), no Distrito Federal (Rio de Janeiro, 1931-1935) e como Secretário de Educação e Saúde do Estado da Bahia (1947-1951). Em síntese, eleger o espaço escolar como objeto de estudo configura-se como uma possibilidade de diálogo entre a Arquitetura e a Educação, ambas responsáveis pela organização e ocupação do espaço físico da escola, bem como com a sua utilização, além de tudo, como espaços educativos.
Escolas Normais: contribuição para a modernização do Estado do Paraná (1904 a 1927)
Authors: Correia Ana Paula Pupo
Published: September 2013

Este artigo pretende discutir por que as cidades de Curitiba, Paranaguá e Ponta Grossa, todas localizadas no Estado do Paraná, foram escolhidas para receber a construção das primeiras Escolas Normais no Paraná, no período entre 1904 e 1927. Além disso, como essas escolas foram representadas nos discursos das ações que legitimaram a construção desses edifícios escolares, na visão dos representantes políticos, inspetores do ensino, professores e imprensa.
Redes de empresas e cooperação na formação do condomínio Tech Town
Authors: Rodrigues Ricardo Furtado , Casarotto Filho Nelson , Rovere Renata Lèbre La
Published: September 2013

O artigo apresenta uma pesquisa cujo objetivo foi o de compreender as relações de cooperação existentes em redes de empresas, por meio do estudo do caso do Condomínio Tech Town, localizado no município de Hortolândia, região metropolitana de Campinas, SP. Numa abordagem geral o estudo destaca os principais desafios e oportunidades para o desenvolvimento de um polo produtor de software e serviços globais dentro do contexto de redes. Como resultado, observou-se que, apesar de este Condomínio ter sido criado com o objetivo de desenvolver um polo de alta tecnologia, suas principais empresas estão inseridas em redes globais e pouco contribuem para o desenvolvimento de processos de aprendizado e de inovação das empresas da região.
Hidratação da magnésia e seu efeito ligante em concretos refratários sem cimento
Authors: Souza T. M. , Braulio M. A. L. , Bonadia P. , Pandolfelli V. C.
Published: September 2013

Apesar da hidratação da magnésia constituir uma dificuldade para o seu uso em concretos refratários, trabalhos recentes indicam que o controle da expansão volumétrica associada a esta reação pode ser utilizado para promover o desenvolvimento de resistência mecânica em concretos sem cimento, resultando em um ligante a base de magnésia. Considerando este aspecto, o objetivo do presente trabalho foi avaliar o potencial do MgO e da combinação MgO-SiO2 como agentes ligantes para concretos refratários. Com este propósito utilizou-se três fontes de MgO distintas, um sínter de magnésia e duas magnésias cáusticas. Para o sistema MgO-SiO2, teores distintos de microssílica (1 %-p, 2 %-p e 4%-p) foram adicionados aos concretos a fim de evitar os danos causados pela hidratação da magnésia. Os resultados obtidos destacam que para o sínter de MgO, calcinado acima de 1500 °C, a baixa razão CaO/SiO2 é um dos pré-requisitos para a redução dos efeitos deletérios associados à hidratação. Para as magnésias cáusticas (calcinadas abaixo de 1200 °C) o teor de SiO2 e CaO livre são fundamentais para determinar o efeito ligante e a integridade física final do produto. Além disto, a adição de microssílica apresentou-se como um mecanismo eficiente para controlar a hidratação de diferentes fontes de MgO, entretanto, teores elevados de microssílica podem resultar em uma redução acentuada da fluidez.
Alteração da superfície de velas cerâmicas porosas comerciais, por processo sol-gel, visando o aumento da organofilicidade
Authors: Alves C. R. , Assis O. B. G.
Published: September 2013

Velas cerâmicas empregadas para a filtração doméstica de água consistem de elementos porosos sinterizados a base de aluminossilicatos com larga distribuição de tamanhos de poros e grãos. Esses filtros têm se mostrado úteis na retenção de micropartículas em suspensão por exclusão de tamanhos, mas apresentam baixa eficiência com respeito à remoção de compostos químicos e de micro-organismos. Para elevar sua capacidade de filtração, principalmente de contaminantes orgânicos, alterações superficiais foram conduzidas fazendo uso de revestimento de SiO2 pela técnica de sol-gel dip-coating. Análises indicam que o filme de SiO2 obtido por calcinação gera uma redução média de 3,5 µm nos tamanhos de poros causando uma ligeira queda de pressão na permeação, contudo, a superfície vítrea melhora a organofilicidade elevando a eficiência de remoção de bactérias, principalmente para vazões em baixo fluxo.
New methodology for a faster synthesis of SrSnO3 by the modified Pechini method
Authors: Lucena G. L. , Souza J. J. N. , Maia A. S. , Soledade L. E. B. , Longo E. , Souza A. G. , Santos I. M. G.
Published: September 2013

SrSnO3, a perovskite-type complex oxide, was synthesized by the modified Pechini method using two different precursors, tin chloride and metallic tin. The first one is already traditional in the literature and it claims about 30 days, only for the cleaning of tin citrate aiming at the elimination of the chloride. The second route was developed by our research group and saves time, taking 6 h to complete the synthesis of the resin. The results show that SrSnO3 obtained from the metallic tin show a higher short range order, leading to a band gap value higher than those reported in the literature, besides a meaningful reduction in the formation of SrCO3, as compared to the one obtained from tin chloride.