bluuebunny/crossref_metadata_2025 huggingface dataset:
Ribosome profiling: a Hi‐Def monitor for protein synthesis at the genome‐wide scale
Authors: Michel Audrey M. , Baranov Pavel V.
Published: May 2013

Ribosome profiling or ribo‐seq is a new technique that provides genome‐wide information on protein synthesis (GWIPS) in vivo. It is based on the deep sequencing of ribosome protected mRNA fragments allowing the measurement of ribosome density along all RNA molecules present in the cell. At the same time, the high resolution of this technique allows detailed analysis of ribosome density on individual RNAs. Since its invention, the ribosome profiling technique has been utilized in a range of studies in both prokaryotic and eukaryotic organisms. Several studies have adapted and refined the original ribosome profiling protocol for studying specific aspects of translation. Ribosome profiling of initiating ribosomes has been used to map sites of translation initiation. These studies revealed the surprisingly complex organization of translation initiation sites in eukaryotes. Multiple initiation sites are responsible for the generation of N‐terminally extended and truncated isoforms of known proteins as well as for the translation of numerous open reading frames (ORFs), upstream of protein coding ORFs. Ribosome profiling of elongating ribosomes has been used for measuring differential gene expression at the level of translation, the identification of novel protein coding genes and ribosome pausing. It has also provided data for developing quantitative models of translation. Although only a dozen or so ribosome profiling datasets have been published so far, they have already dramatically changed our understanding of translational control and have led to new hypotheses regarding the origin of protein coding genes. WIREs RNA 2013, 4:473–490. doi: 10.1002/wrna.1172

This article is categorized under:

Translation > Ribosome Structure/Function

Translation > Translation Mechanisms

Translation > Translation Regulation

RNA Methods > RNA Analyses in Cells
French Professionals in Genetic Counselor Careers
Authors: Cordier C. , Taris N. , De Pauw A. , Sobol H. , Philip N. , Voelckel M.‐A.
Published: May 2013

The profession of genetic counseling in France was recognized in 2004, based on the recommendations of a mandate commissioned by the Health Minister to explore the medical demographics of France. The report predicted a shortage of health professionals in the field of genetics, particularly in light of the rapid development of molecular testing. Development of the profession was supported by a legal framework, and today 107 genetic counselors have graduated from the specific educational program which awards the Professional Master's Degree of Human Pathology, entitled Master in Genetic Counseling and Predictive Medicine. Here we will trace the development of the profession in France and review the demographic characteristics of the students and genetic counselors practicing the profession today.
Induced pluripotency and direct reprogramming: a new window for treatment of neurodegenerative diseases
Authors: Li Rui , Bai Ye , Liu Tongtong , Wang Xiaoqun , Wu Qian
Published: May 2013

Human embryonic stem cells (hESCs) are pluripotent cells that have the ability of unlimited self-renewal and can be differentiated into different cell lineages, including neural stem (NS) cells. Diverse regulatory signaling pathways of neural stem cells differentiation have been discovered, and this will be of great benefit to uncover the mechanisms of neuronal differentiation in vivo and in vitro. However, the limitations of hESCs resource along with the religious and ethical concerns impede the progress of ESCs application. Therefore, the induced pluripotent stem cells (iPSCs) via somatic cell reprogramming have opened up another new territory for regenerative medicine. iPSCs now can be derived from a number of lineages of cells, and are able to differentiate into certain cell types, including neurons. Patient-specifi c iPSCs are being used in human neurodegenerative disease modeling and drug screening. Furthermore, with the development of somatic direct reprogramming or lineage reprogramming technique, a more effective approach for regenerative medicine could become a complement for iPSCs.
Treatment of neuropathic pain with the capsaicin 8% patch: Quantitative sensory testing (QST) in a prospective observational study identifies potential predictors of response to capsaicin 8% patch treatment
Authors: Gustorff Burkhard , Poole Chris , Kloimstein Herwig , Hacker Nicole , Likar Rudolf
Published: May 2013

Background and aims

Peripheral neuropathic pain (PNeP) is a chronic and disabling condition for which no predictors of response to treatment have yet been identified. Clinical studies show that while many patients with PNeP respond positively to treatment with the capsaicin 8% patch, others do not. This study used quantitative sensory testing (QST) to determine whether any patient characteristics can predict response to treatment with the capsaicin 8% patch.

Methods

This was a prospective, non-placebo-controlled, observational study. Patients used the Visual Analogue Scale (VAS) to assess their pain at baseline and then on Days 1, 7–10 (from here referred to as Day 7/10), 28 and 84 following treatment with the capsaicin 8% patch. QST was undertaken at the same timepoints on the painful area at the region of maximum PNeP and on a contralateral, control area. In addition, the size of the painful area was assessed at baseline and Days 7/10, 28 and 84.

Results

A total of 57 patients were treated. Among 54 evaluable patients, 19 (35.2%) achieved a ≥30% reduction in VAS pain score at Day 7/10 post-treatment compared with baseline — these were defined as ‘responders’. Analysis of the QST data showed that the PNeP area in responders, but not in non-responders, had a significantly lower pressure pain threshold compared with the control area at baseline (median 320 kPa vs. 480 kPa, respectively; p = .004). Furthermore, non-responders had approximately three times greater degree of allodynia at baseline compared with responders across tests using brush, cotton wool and Q-tip. These differences were significant for tests using brush and cotton wool (p = .024 and p = .046, respectively) and approached significance in the test using Q-tip (p = .066). Following treatment with the capsaicin 8% patch, responders showed a trend towards a reduction in warm perception and also appeared to show normalization of the pinprick hyperalgesia at some stimulus levels. Responders to therapy had significantly greater reductions than non-responders in the size of the painful area at Day 28 (p = .011) and Day 84 (p = .005) following treatment. However, both responders and non-responders had meaningful reductions in the size of the painful area compared with baseline values.

Conclusions

This study suggests that differences can be identified in the sensory profiles of patients with PNeP who respond to the capsaicin 8% patch and those who do not, specifically pressure pain threshold and degree of allodynia. Notably, both responders and non-responders experienced meaningful reductions in the size of the painful area following treatment.

Implications

The findings warrant further investigation in a larger number of patients and in prospective trials.
Functional recovery results from the risperidone long-acting injectable versus quetiapine relapse prevention trial (ConstaTRE)
Authors: Rouillon Frédéric , Eriksson Lars , Burba Benjaminas , Raboch Jiri , Kaprinis Georgios , Schreiner Andreas
Published: May 2013

Objective

ConstaTRE is an open-label, randomised, controlled, relapse prevention trial in patients with stable schizophrenia or schizoaffective disorder switched to risperidone long-acting injectable (RLAI) or oral quetiapine, and was designed to test the hypothesis that injectable antipsychotic treatment with risperidone would be more effective than oral therapy with quetiapine. Here we report the functional recovery results from the ConstaTRE trial.

Methods

Clinically stable adults previously treated with oral risperidone, olanzapine, or oral first-generation antipsychotics were randomised to RLAI or quetiapine for 24 months. Functional recovery was assessed using the Social and Occupational Functioning Assessment Scale (SOFAS) and two quality-of-life (QoL) measures [Medical Outcomes Survey Short Form-12 (SF-12) and Schizophrenia Quality-of-Life Scale Revision 4 (SQLS-R4)].

Results

A total of 666 patients were randomised and treated with RLAI (n = 329) or quetiapine (n = 337). Relapse occurred in 16.5% RLAI and 31.3% quetiapine patients. Significant improvements in SOFAS, SF-12, and SQLS-R4 scores were observed from baseline to month 24 with both RLAI and quetiapine. At months 6, and 12, and endpoint, improvement in SOFAS score was significantly greater for RLAI than quetiapine (p < 0.05).

Conclusions

Among patients with stable schizophrenia or schizoaffective disorder, the likelihood of functional recovery appears to be higher in those switching to RLAI than to quetiapine, although improvements in functional status and QoL were observed with both treatments.
Methodological considerations for meal-induced thermogenesis: measurement duration and reproducibility
Authors: Ruddick-Collins Leonie C. , King Neil A. , Byrne Nuala M. , Wood Rachel E.
Published: May 2013

Meal-induced thermogenesis (MIT) research findings have been highly inconsistent, in part, due to the variety of durations and protocols used to measure MIT. In the present study, we aimed to determine the following: (1) the proportion of a 6 h MIT response completed at 3, 4 and 5 h; (2) the associations between the shorter durations and the 6 h measures; (3) whether shorter durations improved the reproducibility of the measurement. MIT was measured in response to a 2410 kJ mixed composition meal in ten individuals (five males and five females) on two occasions. Energy expenditure was measured continuously for 6 h post-meal using indirect calorimetry, and MIT was calculated as the increase in energy expenditure above the pre-meal RMR. On average, 76, 89 and 96 % of the 6 h MIT response was completed within 3, 4 and 5 h, respectively, and MIT at each of these time points was strongly correlated with the 6 h MIT response (range for correlations, r 0·990–0·998; P< 0·01). The between-day CV for the 6 h measurement was 33 %, but it was significantly lower after 3 h of measurement (CV 26 %; P= 0·02). Despite variability in the total MIT between days, the proportion of MIT that was completed at 3, 4 and 5 h was reproducible (mean CV: 5 %). While 6 h are typically required to measure the complete MIT response, the 3 h measures provide sufficient information about the magnitude of the MIT response and may be applicable for testing individuals on repeated occasions.
The Form and Function of Nineteenth-Century Missionary Periodicals: Introduction
Authors: Jensz Felicity , Acke Hanna
Published: May 2013

At the 1860 conference on Protestant missions held in Liverpool, a session was dedicated to the use of the reported 200,000 monthly missionary periodicals produced by various societies for encouraging the home support of missionary work. The 125 delegates from more than twenty-five Protestant missionary societies both in Britain and abroad had divergent opinions on the prospective contents and audiences for missionary periodicals. One thing that they did agree upon, however, was their necessity. The Reverend Thomas Green from the Church Missionary Society noted that missionary periodicals provided a means of “influencing” the minds of readers in order to excite the missionary spirit among the home community. The high circulation of missionary periodicals was, according to the Secretary of the Baptist Missionary Society, Reverend Frederick Trestrail, an indication that they provided a source of information that was received willingly and consumed by the masses.
The Function of Inaugural Editorials in Missionary Periodicals
Authors: Jensz Felicity
Published: May 2013

During the nineteenth century, over 300 missionary periodicals were established in Britain, along with hundreds in North America, Europe, and the colonial world, yet little has been written about the rationale behind their establishment. From their beginnings as sources of intelligence, periodicals developed into vehicles of influence by the first decades of the nineteenth century, with missionary organizations also using this reduplicated commodity to deliberately persuade and mold public attitudes. This article examines some thirty inaugural editorials and first volume prefaces to Protestant missionary periodicals, including those from “new series,” to uncover how editors justified their establishment to their potential readership.
Media Events and Missionary Periodicals: The Case of the Boxer War, 1900–1901
Authors: Klein Thoralf
Published: May 2013

Missionary periodicals, like their secular counterparts (newspapers and magazines), had the potential to create and sustain media events—those rare and precious times when news coverage breaks out of the confines of its daily routines, allowing contemporaneous themes to surface and occupy center stage. However, mission publications had their specific ways of presenting these issues, which are cast most sharply into relief when the underlying occurrences affected both missions and society at large. It is at those junctures that mission publications became more receptive towards broader political, social, and cultural trends; conversely, society took greater notice of missionary activities than usual during these times.
The Burdens of Church History
Authors: Maffly-Kipp Laurie F.
Published: May 2013

In 1922, George Freeman Bragg, rector of an Episcopal Church in Baltimore, published a volume detailing the work of his fellow church members from the colonial era to the present. He painstakingly recorded baptisms, catechists, church growth, church debates, social outreach, and listed prominent leaders in the movement. His work was, in many respects, unremarkable, one of many garden-variety “church histories” that still line the shelves of seminaries and colleges around the country. Their production reminds us of an era of abundant confidence in the efficacy of religious institutions to shape society, and of histories to mold the future of Christian communities.
Prospective inter-relationships between late adolescent personality and major depressive disorder in early adulthood
Authors: Wilson S. , DiRago A. C. , Iacono W. G.
Published: May 2013

Background

A well-established body of literature demonstrates concurrent associations between personality traits and major depressive disorder (MDD), but there have been relatively few investigations of their dynamic interplay over time.

Method

Prospective inter-relationships between late-adolescent personality and MDD in early adulthood were examined in a community sample of male and female twins from the Minnesota Twin Family Study (MTFS; n = 1252). Participants were classified into naturally occurring MDD groups based on the timing (adolescent versus adult onset) and course (chronic/recurrent versus remitting) of MDD. MDD diagnoses were assessed at ages 17, 20, 24 and 29 years, and personality traits [negative emotionality (NEM), positive emotionality (PEM) and constraint (CON)] were assessed at ages 17, 24 and 29 years.

Results

Multilevel modeling (MLM) analyses indicated that higher age-17 NEM was associated with the subsequent development of MDD, and any MDD, regardless of onset or course, was associated with higher NEM up to age 29. Moreover, the chronic/recurrent MDD groups failed to show the normative decrease in NEM from late adolescence to early adulthood. Lower age-17 PEM was also associated with the subsequent development of MDD but only among the chronic/recurrent MDD groups. Finally, the adolescent-onset MDD groups reported lower age-17 CON relative to the never-depressed and adult-onset MDD groups.

Conclusions

Taken together, the results speak to the role of personality traits for conferring risk for the onset of MDD in late adolescence and early adulthood, in addition to the pernicious implications of chronic/recurrent MDD, particularly when it onsets during adolescence, for adaptive personality development.
Virgil's Augustan Temples: Image and Intertext in theAeneid
Authors: Kirichenko Alexander
Published: May 2013

This article discusses the most memorable works of art described in Virgil'sAeneid(the paintings at the temple in Carthage, the doors of the temple in Cumae, the shield of Aeneas, and the baldric of Pallas) as visual models for the poem's organization of its own intertextual memory. The multi-dimensionality of memory enacted in the viewing of these pictorial programmes emerges as a metaphorical visualization of the semantic density created by the overlapping intertexts within the narrative itself and, what is more, urges the reader to perceive works of Augustan monumental art as embodiments of a similarly complex universe of memory.
Destructive attraction: factors that influence hunting pressure on the Blue Bird-of-paradiseParadisaea rudolphi
Authors: VAN DEN BERGH MICHIEL O. L. , KUSTERS KOEN , DIETZ A. J. (TON)
Published: May 2013

The Blue Bird-of-paradiseParadisaea rudolphi(BBOP) is a globally threatened species restricted to the montane rainforest of Papua New Guinea (PNG). Local inhabitants hunt the BBOP for its feathers, which is one of the main reasons for its population decline. The feathers are used for both traditional and commercial purposes. So far virtually nothing is known about which factors enhance or decrease hunting pressure, and how this is influenced by ongoing market integration of local communities. Field research in PNG suggests that the demand for BBOP feathers and, with that, the collection intensity, primarily stem from traditional uses, such as head decoration. Interest in the traditional use of the feathers is particularly high in remote villages, while the value attributed to living birds is higher in less remote villages, suggesting a decrease of BBOP collection intensity with increased market integration. However, increased access to ‘outside influences’ (namely tourism and Christianity) may both decrease as well as increase hunting pressures. Finally, we argue that awareness-raising among local people, government officials and tourists may well be the most sensible conservation measure.
The impact of introduced predators on an island endemic, the St Helena Plover, Charadrius sanctaehelenae
Authors: BURNS FIONA , MCCULLOCH NEIL , SZÉKELY TAMÁS , BOLTON MARK
Published: May 2013

We investigated the impact of introduced predators on the productivity of the St Helena Plover Charadrius sanctaehelenae, a shorebird endemic to the South Atlantic island of St Helena. The nest predator species identified have all been introduced to St Helena in the last 510 years, and all are species that are known to be invasive on other islands. The species responsible for taking the largest proportion of eggs was the domestic cat Felis catus, with rats (Rattus rattus or R. norvegicus) and Common Myna Acridotheres tristis taking smaller proportions. Nest survival varied spatially and was correlated with an index of cat density. No relationship was observed between the number of nesting attempts per pair in a year and predator density. The resulting estimates of productivity were insufficient in some areas to allow stable populations to persist locally. Future work should focus on assessing the population level impacts of current and reduced predator densities to St Helena Plovers, and understanding the influence of resource availability and habitat structure on the densities and impacts of predators.
General and specific paraphrases of semantic relations between nouns
Authors: NULTY PAUL , COSTELLO FINTAN
Published: May 2013

Many English noun pairs suggest an almost limitless array of semantic interpretation. A fruit bowl might be described as a bowl for fruit, a bowl that contains fruit, a bowl for holding fruit, or even (perhaps in a modern sculpture class), a bowl made out of fruit. These interpretations vary in syntax, semantic denotation, plausibility, and level of semantic detail. For example, a headache pill is usually a pill for preventing headaches, but might, perhaps in the context of a list of side effects, be a pill that can cause headaches (Levi, J. N. 1978. The Syntax and Semantics of Complex Nominals. New York: Academic Press.). In addition to lexical ambiguity, both relational ambiguity and relational vagueness make automatic semantic interpretation of these combinations difficult. While humans parse these possibilities with ease, computational systems are only recently gaining the ability to deal with the complexity of lexical expressions of semantic relations. In this paper, we describe techniques for paraphrasing the semantic relations that can hold between nouns in a noun compound, using a semi-supervised probabilistic method to rank candidate paraphrases of semantic relations, and describing a new method for selecting plausible relational paraphrases at arbitrary levels of semantic specification. These methods are motivated by the observation that existing semantic relation classification schemes often exhibit a highly skewed class distribution, and that lexical paraphrases of semantic relations vary widely in semantic precision.
DRD2/ANKK1 Taq1A polymorphism (rs1800497) has opposing effects on D2/3 receptor binding in healthy controls and patients with major depressive disorder
Authors: Savitz Jonathan , Hodgkinson Colin A. , Martin-Soelch Chantal , Shen Pei-Hong , Szczepanik Joanna , Nugent Allison C. , Herscovitch Peter , Grace Anthony A. , Goldman David , Drevets Wayne C.
Published: May 2013

The A1 allele of the DRD2/ANKK1 Taq1A polymorphism (rs1800497) is associated with reduced striatal D2/3 receptor binding in healthy individuals (Con) as well as depression and addiction. However, the effect of rs1800497 on D2/3 receptor binding in depressed patients as well as the SNP's effect on D2/3 binding during reward-associated dopamine release is unknown. Twelve unmedicated patients with major depressive disorder (MDD) and 24 Con completed PET scans with [11C]raclopride, once without receiving monetary rewards (baseline) and once while winning money. In Con, the A1 allele was associated with reduced baseline binding potential (BPND) in the middle caudate and ventral striatum. However, in MDD patients the A1 allele was associated with increased baseline BPND in these regions. There were no significant associations between rs1800497 and change in BPND during reward-associated dopamine release. Conceivably, the A1 allele predisposes to depression and addiction via its effect on the post-synaptic D2 receptor.
Antidepressant, mood stabilizing and procognitive effects of very low dose sublingual ketamine in refractory unipolar and bipolar depression
Authors: Lara Diogo R. , Bisol Luisa W. , Munari Luciano R.
Published: May 2013

Intravenous ketamine (0.5 mg/kg) produces robust, rapid and long-lasting antidepressant effects, but is unpractical. Sublingual administration of ketamine renders better bioavailability (∼30%) and less conversion to norketamine than oral administration. We evaluated the therapeutic effects and tolerability of very low dose sublingual (VLDS) racemic ketamine (10 mg from a 100 mg/ml solution for 5 min and swallowed), repeatedly administered every 2–3 d or weekly, in 26 out-patients with refractory unipolar or bipolar depression. According to patients' reports, VLDS ketamine produced rapid, clear and sustained effects, improving mood level and stability, cognition and sleep in 20 patients (77%), with only mild and transient light-headedness as a common side-effect (no euphoria, psychotic or dissociative symptoms). Remission remained in some patients after stopping ketamine. Thus, VLDS ketamine may have broad spectrum effects beyond its antidepressant properties, with rapid onset of action, high efficacy, good tolerability and low cost, allowing extended treatment as needed.
Ageing dynamics of ion bombardment induced self-organization processes
Authors: Bikondoa Oier , Carbone Dina , Chamard Virginie , Metzger Till Hartmut
Published: May 2013

Instabilities caused during the erosion of a surface by an ion beam can lead to the formation of self-organized patterns of nanostructures. Understanding the self-organization process requires not only the in-situ characterization of ensemble averaged properties but also probing the dynamics. This can be done with the use of coherent X-rays and analyzing the temporal correlations of the scattered intensity. Here, we show that the dynamics of a semiconductor surface nanopatterned by normal incidence ion beam sputtering are age-dependent and slow down with sputtering time. This work provides a novel insight into the erosion dynamics and opens new perspectives for the understanding of self-organization mechanisms.
Convergent evolution of chromatin modification by structurally distinct enzymes: comparative enzymology of histone H3 Lys27 methylation by human polycomb repressive complex 2 and vSET
Authors: Swalm Brooke M. , Hallenbeck Kenneth K. , Majer Christina R. , Jin Lei , Scott Margaret Porter , Moyer Mikel P. , Copeland Robert A. , Wigle Tim J.
Published: May 2013

H3K27 (histone H3 Lys27) methylation is an important epigenetic modification that regulates gene transcription. In humans, EZH (enhancer of zeste homologue) 1 and EZH2 are the only enzymes capable of catalysing methylation of H3K27. There is great interest in understanding structure–function relationships for EZH2, as genetic alterations in this enzyme are thought to play a causal role in a number of human cancers. EZH2 is challenging to study because it is only active in the context of the multi-subunit PRC2 (polycomb repressive complex 2). vSET is a viral lysine methyltransferase that represents the smallest protein unit capable of catalysing H3K27 methylation. The crystal structure of this minimal catalytic protein has been solved and researchers have suggested that vSET might prove useful as an EZH2 surrogate for the development of active site-directed inhibitors. To test this proposition, we conducted comparative enzymatic analysis of human EZH2 and vSET and report that, although both enzymes share similar preferences for methylation of H3K27, they diverge in terms of their permissiveness for catalysing methylation of alternative histone lysine sites, their relative preferences for utilization of multimeric macromolecular substrates, their active site primary sequences and, most importantly, their sensitivity to inhibition by drug-like small molecules. The cumulative data led us to suggest that EZH2 and vSET have very distinct active site structures, despite the commonality of the reaction catalysed by the two enzymes. Hence, the EZH2 and vSET pair of enzymes represent an example of convergent evolution in which distinct structural solutions have developed to solve a common catalytic need.
Maturation of the cytochrome cd1 nitrite reductase NirS from Pseudomonas aeruginosa requires transient interactions between the three proteins NirS, NirN and NirF
Authors: Nicke Tristan , Schnitzer Tobias , Münch Karin , Adamczack Julia , Haufschildt Kristin , Buchmeier Sabine , Kucklick Martin , Felgenträger Undine , Jänsch Lothar , Riedel Katharina , Layer Gunhild
Published: May 2013

The periplasmic cytochrome cd1 nitrite reductase NirS occurring in denitrifying bacteria such as the human pathogen Pseudomonas aeruginosa contains the essential tetrapyrrole cofactors haem c and haem d1. Whereas the haem c is incorporated into NirS by the cytochrome c maturation system I, nothing is known about the insertion of the haem d1 into NirS. Here, we show by co-immunoprecipitation that NirS interacts with the potential haem d1 insertion protein NirN in vivo. This NirS–NirN interaction is dependent on the presence of the putative haem d1 biosynthesis enzyme NirF. Further, we show by affinity co-purification that NirS also directly interacts with NirF. Additionally, NirF is shown to be a membrane anchored lipoprotein in P. aeruginosa. Finally, the analysis by UV–visible absorption spectroscopy of the periplasmic protein fractions prepared from the P. aeruginosa WT (wild-type) and a P. aeruginosa ΔnirN mutant shows that the cofactor content of NirS is altered in the absence of NirN. Based on our results, we propose a potential model for the maturation of NirS in which the three proteins NirS, NirN and NirF form a transient, membrane-associated complex in order to achieve the last step of haem d1 biosynthesis and insertion of the cofactor into NirS.
Linking Infant-Directed Speech and Face Preferences to Language Outcomes in Infants at Risk for Autism Spectrum Disorder
Authors: Droucker Danielle , Curtin Suzanne , Vouloumanos Athena
Published: May 2013

Purpose

In this study, the authors aimed to examine whether biases for infant-directed (ID) speech and faces differ between infant siblings of children with autism spectrum disorder (ASD) (SIBS-A) and infant siblings of typically developing children (SIBS-TD), and whether speech and face biases predict language outcomes and risk group membership.

Method

Thirty-six infants were tested at ages 6, 8, 12, and 18 months. Infants heard 2 ID and 2 adult-directed (AD) speech passages paired with either a checkerboard or a face. The authors assessed expressive language at 12 and 18 months and general functioning at 12 months using the Mullen Scales of Early Learning (Mullen, 1995).

Results

Both infant groups preferred ID to AD speech and preferred faces to checkerboards. SIBS-TD demonstrated higher expressive language at 18 months than did SIBS-A, a finding that correlated with preferences for ID speech at 12 months. Although both groups looked longer to face stimuli than to the checkerboard, the magnitude of the preference was smaller in SIBS-A and predicted expressive vocabulary at 18 months in this group. Infants' preference for faces contributed to risk-group membership in a logistic regression analysis.

Conclusion

Infants at heightened risk of ASD differ from typically developing infants in their preferences for ID speech and faces, which may underlie deficits in later language development and social communication.
Analysis and implementation of an interleaved series input parallel output active clamp forward converter
Authors: Chen Shin‐Ju , Yang Sung‐Pei , Cho Meng‐Fu
Published: May 2013

A novel dual active clamp forward topology with interleaved series input parallel output (ISIPO) structure is proposed here. The ISIPO active clamp forward converter enables the converter cells to share the input voltage and output current. The interleaved operation can diminish the output current ripple in the output capacitor. The output capacitance of switching devices and the resonant inductance are utilised to realise the resonance at the transition interval of switches such that the zero‐voltage‐switching operation for all switches can be achieved. Moreover, the energy stored in the transformer leakage inductance is recycled such that the voltage stresses of switching devices are reduced. All these features make the proposed converter suitable for the DC–DC converters with high input voltage, high output current and high‐efficiency applications. The operating principle and design considerations are provided in detail. Finally, experimental results based on a 240 W(12 V/20 A) prototype with an input voltage of 400 V are presented to verify the theoretical analysis and circuit performance.
Single‐stage high‐power‐factor low‐frequency square‐wave‐driven high‐intensity‐discharge lamp ballast
Authors: Cheng Chun‐An , Cheng Hung‐Liang , Chung Tsung‐Yuan , Ku Chen‐Wei
Published: May 2013

This study presents a single‐stage electronic ballast for the high‐intensity‐discharge (HID) lamp with high‐power factor. The presented ballast consists of a discontinuous‐conduction‐mode operated dual‐boost converter to achieve input current shaping, and a high‐frequency combined with a low‐frequency square‐wave‐driven half‐bridge‐type inverter for supplying the HID lamp with low‐frequency square‐wave sources. The attractive features of the proposed ballast are high‐power factor (> 0.99), low total harmonic distortion of input utility‐line current (< 10%), high efficiency (> 90%), cost‐effectiveness and freedom from acoustic resonance. The operational principles, design guidelines and a design example are included in this paper. A prototype ballast circuit has been successfully implemented and tested for supplying three different brands of 70W HID lamps operating with 110 V‐root‐mean‐square input utility‐line voltage. Satisfactory experimental results demonstrate the functionalities of the proposed ballast.
Full digital deadbeat speed control for permanent magnet synchronous motor with load compensation
Authors: Wang Shaowei , Wan Shanming
Published: May 2013

A full digital deadbeat controller is proposed for the speed loop to obtain better dynamic response performance in permanent magnet synchronous motor servo system. Given an expected target error function and speed command in Z‐domain form, according to the deadbeat zero‐pole configuration rules, the digital controller is derived to make the current command output stable in several sampling periods and the speed response also becomes stable without ripples. To reject disturbance from the load variation, an estimation method, based on model reference adaptive system through Popov's hyper stability criteria, is presented to identify online the moment of inertia and load torque. The two quantities are essential for the speed loop to achieve adaptive control by load compensation. The simulation and experimental results reveal the effectiveness of the proposed speed controller.
Z(TN)‐Observability and control of parallel multicell chopper using Petri nets
Authors: Amghar Bilal , Darcherif Abdelmoumen , Barbot Jean‐Pierre
Published: May 2013

This study deals with observability problems and control of the parallel multicell chopper. In the area of strong currents with high switching frequencies, new structures based on the combination of components have been developed. Among them, the authors find the parallel multicell converters that the authors studied in this study. This type of choppers is a DC/DC static power converter which has an output current equals to n (n is the number of cells) times the source current. After recalling the dynamical equations of the converter, its hybrid dynamical behaviour and properties are highlighted. This particular hybrid system induces new and difficult observability problems, such problem can be tackled by a new observability concept [the Z(TN)‐observability]. However, for a large number of switching cells in parallel, the complexity of the system makes it impossible to predict the transient behaviour of the converter and therefore all predimensioning. The main disadvantage of this type of converter is the imbalance branches of current with increasing number of cells. Therefore modelling and control with Petri net is proposed to solve the problems of imbalanced of currents and the voltage output regulation with variation of the load. The authors approaches are attested by several numerical simulations considering noisy measurements and load variations.
Active current ripple cancellation in parallel connected buck converter modules
Authors: Tsang Chi‐Wa , Foster Martin , Stone David , Gladwin Dan
Published: May 2013

Parallel connection of converters has become a popular method of improving efficiency. This study first presents a design technique for a buck converter with two parallelly connected power modules (PMs), where one PM is designed with large current ripple for high efficiency. This study then demonstrates an active current ripple cancellation technique, where the current waveform of the second PM is shaped to be the exact opposite to that in the first PM, to reduce the current ripple as seen by the output capacitor. The factors that affect the overall efficiency in a parallel connected converter and the calculation of the parameters that determine the effectiveness of the ripple cancellation are reported. A prototype parallel converter is designed based on the proposed converter design technique and the current ripple seen by the output capacitor is successfully reduced by 66% with the proposed ripple cancellation technique, under different line and load conditions.
Analysis and experimental verification of Hopf bifurcation in a solar photovoltaic powered hysteresis current‐controlled cascaded‐boost converter
Authors: Deivasundari ParvathyShankar , Uma Govindarajan , Poovizhi Rengasamy
Published: May 2013

In this study, the non‐linear dynamics of a two‐stage cascaded‐boost converter, which is a popular choice, for solar energy systems is investigated. The stability of the system is studied with the aid of non‐linear state equations derived from an averaged continuous model. Analysis of the describing autonomous equations reveals that the system loses stability via supercritical Hopf bifurcation. Extensive computer simulations are performed to capture the system's dynamic behaviour and demarcate the bifurcation boundaries. Furthermore, the possibility of subcritical Hopf bifurcation for variation in input voltage is also examined. Trajectory and Poincaré section before and after the bifurcation are shown. Experimental results are also provided to confirm the observed bifurcation scenario.
Unified time‐domain formulation of switching frequency for hysteresis current controlled AC/DC and DC/AC grid connected converters
Authors: Gautam Shweta , Gupta Rajesh
Published: May 2013

This study presents a unified time‐domain formulation of switching frequency for hysteresis current controlled AC/DC and DC/AC grid connected converters. It is shown that the generalised expression of switching frequency obtained can be used for any mode of operation of the converter based on phase relation between the reference AC current and grid voltage. The presented analysis provides information of maximum, minimum and average switching frequencies for all modes of the converter operation. The analytical results derived under different configurations are verified through the experimental results obtained using FPGA‐based implementation of the controller for the converter. The applications of the results are shown on the three different single‐phase systems operating in current control mode: (i) static synchronous compensator, (ii) boost rectifier and (iii) grid interface of wind‐turbine system. The results of switching operations in these applications are verified using simulation studies performed in power systems CAD/electromagnetic transients including DC (PSCAD/EMTDC) software.
Source switching circuit with low‐gate‐driving loss in high‐voltage buck light emitting diode driver
Authors: Liao Tse‐Ju , Hung Chia‐Chieh , Chen Chern‐Lin
Published: May 2013

Source switching circuit with low‐gate‐driving loss in high‐voltage buck light emitting diode (LED) driver is proposed in this study. Source switching circuit comprises of a high‐voltage power metal‐oxide semiconductor field‐effect transistor (MOSFET) (HVMOS) and a low‐voltage power MOSFET (LVMOS) in series, a capacitor and a Zener diode. By switching the HVMOS by different source voltage and constant gate voltage, it recycles gate charges of HVMOS to reduce gate‐driving loss. Gate charges are recycled in the capacitor when LVMOS is turning off, and can be reused when LVMOS is turning on. This circuit also provides a new power feeding route for control chip, and power consumption is relatively low on the proposed route. The power feeding route also improves power efficiency. With a 12 W LED load, the experiment shows that the efficiency of the proposed driving circuit is improved by 3.7% with 156 V input voltage and 4.8% with 326 V input voltage compared with the converter using single HVMOS.
Grid simulator for power quality assessment of micro‐grids
Authors: Eloy‐García Joaquin , Vasquez Juan Carlos , Guerrero Josep M.
Published: May 2013

In this study, a grid simulator based on a back‐to‐back inverter topology with resonant controllers is presented. The simulator is able to generate three‐phase voltages for a range of amplitudes and frequencies with different types of perturbations, such as voltage sags, steady‐state unbalanced voltages, low‐order harmonics and flicker. The aim of this equipment is to test the performance of a given system under such distorted voltages. A prototype of the simulator, consisting of two inverters connected back‐to‐back to a 380 V three‐phase grid and feeding a micro‐grid composed of two‐inverter interfaced distributed generators and a critical load was built and tested. A set of experimental results for linear purely resistive loads, non‐linear loads and current‐controlled inverters is presented to prove the capabilities of the simulator. Finally, a case study is presented by testing a micro‐grid.
Design of backstepping control for high‐performance inverter with stand‐alone and grid‐connected power‐supply modes
Authors: Wai Rong‐Jong , Lin Chih‐Ying , Wu Wen‐Chuan , Huang Hsin‐Ning
Published: May 2013

In this study, the backstepping control (BSC) design for a high‐performance inverter with the functions of stand‐alone and grid‐connected power supply is developed so that distributed generation units can operate individually or in a micro‐grid mode. In the stand‐alone power‐supply mode, the output ac voltage can supply to ac loads. In the grid‐connected power‐supply mode, the goal of power management can be achieved by controlling the amplitude and direction of the output current in the inverter. As a result, the proposed high‐performance inverter with the BSC scheme has the output voltage with a low total harmonic distortion in the stand‐alone power‐supply mode and the output current with a high‐power factor in the grid‐connected power‐supply mode to provide an ac output with high‐performance power quality. The effectiveness of the proposed high‐performance inverter with the BSC is verified by experimental results of a 3 kW prototype, and the merit of the proposed BSC scheme is indicated in comparison with previous proportional‐integral control, proportional‐resonant control and adaptive total sliding‐mode control strategies.
Improved double line voltage synthesis of matrix converter for input current enhancement under unbalanced power supply
Authors: Yan Yan , An Haijiao , Shi Tingna , Xia Changliang
Published: May 2013

Input voltage unbalance causes input current waveform degradation of matrix converter because of the lack of reactive component in dc link. To reduce the harmonic content of input current, dynamic input current modulation methods based on space vector modulation strategy have been presented in some works. This study proposes two improved double line voltage synthesis (DLVS) strategies for matrix converters. Both strategies apply the dynamic input current modulation methods to DLVS aiming at improving input and output waveforms at the same time. Besides, simplicity is another advantage of the methods proposed in this study. Phase detection of input current modulation vector is eliminated, which reduces the calculation time of control algorithm. Numerical simulations and experiments with a 10 kW prototype are carried out. The results are given to verify the feasibility and effectiveness of the proposed strategies.
On the properties of binary rutile MO2 compounds, M = Ir, Ru, Sn, and Ti: A DFT study
Authors: Novell-Leruth Gerard , Carchini Giuliano , López Núria
Published: May 2013

We have studied the properties of bulk and different surfaces of rutile oxides, IrO2, RuO2, SnO2, and TiO2, and their binary compounds by means of density functional theory. As mixtures are employed in many applications, we have investigated the solubility, segregation, and overlayer formation of one of these oxides on a second metal from the series, as these aspects are critical for the chemical and electrochemical performances. Our results show that the bulk solubility is possible for several combinations. The electronic structure analysis indicates the activation of Ir states in IrxTi1−xO2 mixtures when compared to the parent IrO2 compound or the reduction in the band gap of TiO2 when Sn impurities are present. Segregation and oxygen-induced segregation of the second metal for the most common surfaces show a great extent of possibilities ranging from strong segregation to antisegregation, which depends on the oxygen ambient. The interaction of guest rutile overlayers on hosts is favourable and a wide range of growth properties (from multilayer formation to tridimensional particles) can be observed. Finally, a careful comparison with experimental information is presented, and for those cases where no data is available, the computed database can be used as a guideline by experimentalists.
On the structural stability of CeN at high pressures: Ab initio calculations
Authors: Sahoo B. D. , Joshi K. D. , Gupta Satish C.
Published: May 2013

The structural stability of CeN under hydrostatic compression has been analyzed theoretically. The comparison of enthalpies calculated as a function of hydrostatic compression for rocksalt type (B1), tetragonal (B10), and CsCl type (B2) structures suggests that the B1 phase will transform to B10 structure at ∼53 GPa, which upon further compression will transform to B2 phase at ∼200 GPa. However, the static high pressure energy dispersive x-ray diffraction measurements on CeN by Olsen et al. [J. Alloys Compd. 533, 29 (2012)] report that the B1 phase transforms directly to B2 phase at ∼65 GPa. To resolve the discrepancy between our calculations and experimental results, we have performed lattice dynamic calculations on these structures. The phonon spectra calculated at zero pressure correctly show B1 phase to be dynamically stable, and B10 and B2 to be unstable. At 60 GPa, the B1 phase becomes dynamically unstable and the B10 structure emerges as a dynamically stable phase whereas B2 still remains unstable. At still higher pressure of ≥200 GPa, the B2 phase becomes not only the lowest enthalpy structure but also dynamically stable. These findings support the results of our static lattice calculations. Further, our calculated angle dispersive x-ray diffraction pattern of B1, B10, and B2 phases shows that most of the diffraction peaks of B10 phase except few weak peaks coincide with the peaks of either B1 or B2 phase; which may pose a difficulty in unambiguously identifying the high pressure phase until a sufficient amount of B1 phase is transformed to the new structure so that the weak peaks, if present, are also visible.