bluuebunny/crossref_metadata_2025 huggingface dataset:
Structural adaptations for ram ventilation: Gill fusions in scombrids and billfishes
Authors: Wegner Nicholas C. , Sepulveda Chugey A. , Aalbers Scott A. , Graham Jeffrey B.
Published: October 2012

For ram‐gill ventilators such as tunas and mackerels (family Scombridae) and billfishes (families Istiophoridae, Xiphiidae), fusions binding the gill lamellae and filaments prevent gill deformation by a fast and continuous ventilatory stream. This study examines the gills from 28 scombrid and seven billfish species in order to determine how factors such as body size, swimming speed, and the degree of dependence upon ram ventilation influence the site of occurrence and type of fusions. In the family Scombridae there is a progressive increase in the reliance on ram ventilation that correlates with the elaboration of gill fusions. This ranges from mackerels (tribe Scombrini), which only utilize ram ventilation at fast cruising speeds and lack gill fusions, to tunas (tribe Thunnini) of the genus Thunnus, which are obligate ram ventilators and have two distinct fusion types (one binding the gill lamellae and a second connecting the gill filaments). The billfishes appear to have independently evolved gill fusions that rival those of tunas in terms of structural complexity. Examination of a wide range of body sizes for some scombrids and billfishes shows that gill fusions begin to develop at lengths as small as 2.0 cm fork length. In addition to securing the spatial configuration of the gill sieve, gill fusions also appear to increase branchial resistance to slow the high‐speed current produced by ram ventilation to distribute flow evenly and optimally to the respiratory exchange surfaces. J. Morphol. 2012. © 2012 Wiley Periodicals, Inc.
Dopamine modulates the off pathway in light‐adapted mouse retina
Authors: Yang Jinnan , Pahng Joshua , Wang Guo‐Yong
Published: October 2012

DL‐2‐Amino‐4‐phosphonobutyric acid (APB) is often used as a tool to block On pathways in studies of interactions between On and Off pathways in retinas. APB is an agonist of mGluR6 receptors and hyperpolarizes the On cone bipolar cells and rod bipolar cells. How APB affects Off responses of retinal ganglion cells (RGCs) in mouse retinas under dark and light adaptation is not clear. The light‐evoked excitatory postsynaptic currents (light‐evoked EPSCs) from Off and On–Off RGCs cells were recorded using whole‐cell patch‐clamp recording to assess how APB affects Off responses (light‐evoked Off EPSCs) of RGCs in dark‐ and light‐adapted mouse retinas. We found that APB differentially affected Off responses of RGCs in dark‐ and light‐adapted mouse retinas. Under dark adaptation, while the APB‐sensitive Off responses were blocked, APB increased the remaining Off responses (mainly from the secondary rod Off pathways) via removal of inhibition from On pathways to Off pathways. Under light adaptation, APB decreased Off responses. Glycinergic and GABAergic antagonists did not prevent the APB‐induced reduction of Off responses of RGCs; however, a dopaminergic type 1 receptor (D1) blocker (SCH 23390) and a hyperpolarization‐activated cyclic nucleotide‐gated (HCN) channel blocker (ZD 7288) prevented the APB‐induced reduction of Off responses of RGCs under light adaptation. The results indicated afunctional circuit: On cone bipolar cells to Off cone bipolar cells via D1 receptors and HCN channels. © 2012 Wiley Periodicals, Inc.
Changes in in vivo knee contact forces through gait modification
Authors: Kinney Allison L. , Besier Thor F. , Silder Amy , Delp Scott L. , D'Lima Darryl D. , Fregly Benjamin J.
Published: October 2012

Knee osteoarthritis (OA) commonly occurs in the medial compartment of the knee and has been linked to overloading of the medial articular cartilage. Gait modification represents a non‐invasive treatment strategy for reducing medial compartment knee force. The purpose of this study was to evaluate the effectiveness of a variety of gait modifications that were expected to alter medial contact force. A single subject implanted with a force‐measuring knee replacement walked using nine modified gait patterns, four of which involved different hiking pole configurations. Medial and lateral contact force at 25, 50, and 75% of stance phase, and the average value over all of stance phase (0–100%), were determined for each gait pattern. Changes in medial and lateral contact force values relative to the subject's normal gait pattern were determined by a Kruskal–Wallis test. Apart from early stance (25% of stance), medial contact force was most effectively reduced by walking with long hiking poles and wide pole placement, which significantly reduced medial and lateral contact force during stance phase by up to 34% (at 75% of stance) and 26% (at 50% of stance), respectively. Although this study is based on data from a single subject, the results provide important insight into changes in medial and lateral contact forces through gait modification. The results of this study suggest that an optimal configuration of bilateral hiking poles may significantly reduce both medial and lateral compartment knee forces in individuals with medial knee osteoarthritis. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 434–440, 2013
Highly reliable a‐IGZO TFTs on a plastic substrate for flexible AMOLED displays
Authors: Nakano Shintaro , Saito Nobuyoshi , Miura Kentaro , Sakano Tatsunori , Ueda Tomomasa , Sugi Keiji , Yamaguchi Hajime , Amemiya Isao , Hiramatsu Masato , Ishida Arichika
Published: October 2012

We have successfully reduced threshold voltage shifts of amorphous In–Ga–Zn–O thin‐film transistors (a‐IGZO TFTs) on transparent polyimide films against bias‐temperature stress below 100 mV, which is equivalent to those on glass substrates. This high reliability was achieved by dense IGZO thin films and annealing temperature below 300 °C. We have reduced bulk defects of IGZO thin films and interface defects between gate insulator and IGZO thin film by optimizing deposition conditions of IGZO thin films and annealing conditions. Furthermore, a 3.0‐in. flexible active‐matrix organic light‐emitting diode was demonstrated with the highly reliable a‐IGZO TFT backplane on polyimide film. The polyimide film coating process is compatible with mass‐production lines. We believe that flexible organic light‐emitting diode displays can be mass produced using a‐IGZO TFT backplane on polyimide films.
Analysis of volatile components in herbal pair Semen Persicae‐Flos Carthami by GC‐MS and chemometric resolution
Authors: Fu Jiangang , Li Xiaoru , Lu* Hongmei , Liang Yizeng
Published: October 2012

Analysis of volatile components in herbal pair (HP) Semen Persicae‐Flos Carthami (SP‐FC) was performed by GC‐MS coupled with chemometric resolution method (CRM). Furthermore, temperature‐programmed retention indices were used together with mass spectra for identification of the volatile components. With the help of CRM, the two‐dimensional data obtained from GC‐MS instruments were resolved into a pure chromatogram and a mass spectrum of each chemical compound. By use of these methods upon two‐dimensional data, 26, 49, and 59 volatile chemical components in essential oils of single herb Semen Persicae, Flos Carthami, and HP SP‐FC were determined qualitatively and quantitatively, accounting for 78.42, 81.08, and 82.48% total contents of essential oil of single herb Semen Persicae, Flos Carthami, and HP SP‐FC, respectively. It is shown that the accuracy of qualitative and quantitative analysis can be enhanced greatly by means of CRM. It is further demonstrated that the numbers of volatile chemical components of HP SP‐FC are almost the addition of those of two single herbs, but the main volatile chemical components of the former are completely different from those of single herb Semen Persicae or Flos Carthami because of chemical reactions and physical changes occurring in the process of decocting two single herbs. This means that chemical components especially pharmacologically active compounds in the recipe might be different from those of single herbs.
A Platform for Preparation of Monodispersed Fluorescent Conjugated Polymer Microspheres with Core‐Shell Structures
Authors: Wang Shangli , Zhao Wei , Song Jing , Cheng Si , Fan Li‐Juan
Published: October 2012

A strategy to prepare stable monodispersed fluorescent microspheres is developed by modifying the Wessling method to synthesize poly(p‐phenylenevinylene) (PPV) on the surface of a highly crosslinked polymer core. The positively charged PPV polymer precursors (pre‐PPV) are adsorbed onto the core with negative charges on the surface and then the insoluble fluorescent PPVs form after thermal elimination. Each individual sphere is found to possess a very smooth surface with an even distribution of fluorescence by microscopic techniques. Very small coefficient of variance (CV) values of emission intensity (<4.0%) and size (<2.3%) are realized for microspheres prepared in the same batch. The spheres are demonstrated to have good thermal stability and photostability.
Anomalous electrical transport properties of PVA–Ag composite films below room temperature
Authors: Ghosh Pankaj , Ghatak Somenath , Mandal Mrinal K. , Meikap Ajit Kumar
Published: October 2012

The direct current (dc) and alternate current (ac) electrical transport property of polyvinyl alcohol–silver (PVA–Ag) composites has been investigated within a temperature range of 77 ≤ T ≤ 300 K and in the frequency range of 20 Hz to 1 MHz in the presence as well as in the absence of a transverse magnetic field up to 1 T. The dc conductivity follows variable range hopping model. The magnetoconductivity of the samples undergoes a change from negative to positive values with the incorporation of Ag in PVA matrix, which can be interpreted by the dominancy of the forward interference effect prevailing over the wave function shrinkage effect. The ac conductivity follows a power law of frequency, whereas the temperature dependence of frequency exponent “s” can be explained by correlated barrier hopping model. The dielectric behavior of the samples has been governed by the grain and interfacial grain boundary resistance and capacitance. Two activation behaviors are observed from the analysis of grain and interfacial grain boundary contributions. POLYM. COMPOS., 33:1941–1950, 2012. © 2012 Society of Plastics Engineers
Single‐wall carbon nanotubes dispersion behavior and its effects on the morphological and mechanical properties of the electrospun nanofibers
Authors: Nasouri Komeil , Shoushtari Ahmad Mousavi , Kaflou Ali , Bahrambeygi Hossein , Rabbi Amir
Published: October 2012

The dispersion behavior of single‐walled carbon nanotube (SWCNT) has important effects on morphological and mechanical properties of SWCNT composite nanofibers. The relationship of the dispersion conditions with morphological and mechanical characteristics for SWCNT / polyacrylonitrile (PAN) / polyvinylpyrrolidone (PVP) composite nanofibers have been examined. The SEM and TEM analyses of the nanofibers revealed that the deformation in the nanofiber structures increases with increasing concentration of SWCNTs. Tensile results showed that only 2 wt% SWCNT loading to the electrospun composite nanofibers gave rise to 10‐fold and 3‐fold increase in the tensile modulus and tenacity of nanofiber layers, respectively. Essentially, high mechanical properties and uniform morphology of the composite nanofibers were found at SWCNT concentration of ∼2 wt% due to their stable and individual dispersion. POLYM. COMPOS., 33:1951–1959, 2012. © 2012 Society of Plastics Engineers
Experts' opinions on the benefit of an incidental prenatal diagnosis of sex chromosomal aneuploidy: a qualitative interview survey
Authors: Pieters J. J. P. M. , Verhaak C. M. , Braat D. D. M. , van Leeuwen E. , Smits A. P. T.
Published: October 2012

Objective

Incidental findings in prenatal diagnostic testing may or may not have clear prognostic significance for the phenotype. We studied experts' opinions of the benefit and disadvantage of an incidental prenatal diagnosis of a sex chromosomal aneuploidy (SCA).

Methods

We interviewed 16 experts in the field of counseling and treatment of people with SCA and asked 13 clinical geneticists and genetic associates about the clinical relevance of an incidental prenatal diagnosis of SCA.

Results

Most of the experts and clinical geneticists (87.5% and 76.9%, respectively) stated that an incidental prenatal diagnosis of SCA was a benefit for the child and the parents. They acknowledged the possibility of parental decisions to terminate pregnancy. Expert options in screening, training, and treatment of health, behavior, and fertility problems increase with an early diagnosis of SCA.

Conclusion

Most experts favored an incidental prenatal diagnosis of SCA despite the complex counseling issues and their acknowledgment of possible parental decisions to terminate pregnancy. They believed the benefits greatly outweigh the disadvantages. © 2012 John Wiley & Sons, Ltd.
The incident user design in comparative effectiveness research
Authors: Johnson Eric S. , Bartman Barbara A. , Briesacher Becky A. , Fleming Neil S. , Gerhard Tobias , Kornegay Cynthia J. , Nourjah Parivash , Sauer Brian , Schumock Glen T. , Sedrakyan Art , Stürmer Til , West Suzanne L. , Schneeweiss Sebastian
Published: October 2012

Comparative effectiveness research includes cohort studies and registries of interventions. When investigators design such studies, how important is it to follow patients from the day they initiated treatment with the study interventions? Our article considers this question and related issues to start a dialogue on the value of the incident user design in comparative effectiveness research. By incident user design, we mean a study that sets the cohort's inception date according to patients' new use of an intervention. In contrast, most epidemiologic studies enroll patients who were currently or recently using an intervention when follow‐up began. We take the incident user design as a reasonable default strategy because it reduces biases that can impact non‐randomized studies, especially when investigators use healthcare databases. We review case studies where investigators have explored the consequences of designing a cohort study by restricting to incident users, but most of the discussion has been informed by expert opinion, not by systematic evidence. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.
Predicting the reaction mechanism of nucleophilic substitutions at carbonyl and thiocarbonyl centres of esters and thioesters
Authors: Ormazábal‐Toledo Rodrigo , Castro Enrique A. , Santos José G. , Millán Daniela , Cañete Alvaro , Contreras Renato , Campodónico Paola R.
Published: October 2012

In nucleophilic substitution reactions at carbonyl centres, there are two possible channels. The first one occurs when the attack of nucleophilic agents takes place simultaneously with the departure of the nucleofuge. This process is named as concerted. The second possibility is the formation of a reaction intermediate, typically a tetrahedral intermediate from which the nucleofuge departs after passing through a second transition state. This second mechanism is defined as stepwise. Whether a concerted or stepwise mechanism is to be expected for a given reaction depends on several factors. Among these determinants are the nucleophilicity of the attacking group, the leaving group ability of the nucleofuge, and the solvent, which affects both the stability of the intermediate or the transition states involved. The role of the electrophilic centre can however become an important factor that can determine the reaction mechanism. In this work we show that the group nucleophilic Fukui function model may be used to rationalize and to predict the reaction mechanism of the title compounds towards alicyclic amines. In general, when the electrophilic carbon centre is attached to the soft sulfur atom, the reaction mechanism is predicted to follow a stepwise route. When the electrophilic carbon atom is attached to a harder oxygen centre, the reaction mechanism is determined by chemical substitution at the nucleofuge moiety. Experimental verification for a set of four substrates is presented. Copyright © 2012 John Wiley & Sons, Ltd.
Electrical characterization of defects introduced in n‐Si during electron beam deposition of Pt
Authors: Auret F. D. , Coelho S. M. M. , Nel J. M. , Meyer W. E.
Published: October 2012

We have used deep level transient spectroscopy (DLTS) and high resolution DLTS to characterize the defects introduced in epitaxially grown n‐type, P‐doped, Si during electron beam deposition (EBD) of Pt for Schottky contact formation. The identity of some of these defects could be established by comparing their properties to those of well‐known defects introduced by high energy electron irradiation of the same material. The most prominent EBD‐induced defects thus identified were the E‐center (VP center), the A‐center (VO center), interstitial carbon (Ci), and the interstitial carbon–substitutional carbon (CiCs) pair. EBD also introduced some defects that were not observed after high energy electron irradiation. DLTS depth profiling revealed that the main defects, VO and VP, could be detected up to 0.5 µm below the metal–Si interface. Shielding the sample from particles originating in the region of the electron beam significantly reduced defect introduction and resulted in Schottky contacts with improved rectification properties. Finally, we have found that exposing the sample to EBD conditions, without actually depositing metal, introduced a different set of electron traps, not introduced by the EBD process.
Hot pressing and nanostructuring of Bi90Sb10 alloys to concurrently improve mechanical and thermoelectric properties
Authors: Heinz Nicholas A. , Howell Sarah , Wang Heng , Ikeda Teruyuki , Snyder G. Jeffrey
Published: October 2012

The microstructure of Bi90Sb10 composites with separate additions of Ag and As was studied, and measurements of the room temperature transport properties were made to see the effects of hot pressing with and without precipitates. The most successful nanostructured Bi90Sb10 samples were those containing As when annealed for durations of 3 days or less near the solidus temperature. The transport measurements showing similar electrical resistivity and decreased thermal conductivity with the addition of precipitates at room temperature demonstrates the potential of this bulk nanostructuring and synthesis approach in this material system. With further study, this work could be helpful in creating similar complex nanostructured systems which have the potential to yield high‐efficiency thermoelectric materials for low temperature applications.
A reconsideration of the thermodynamics of phase‐change switching
Authors: Tominaga Junji , Wang Xiaomin , Kolobov Alexander V. , Fons Paul
Published: October 2012

Phase‐change random access memory (PCRAM) holds great promise as a future non‐volatile memory technology. All PCRAM devices have an inextricable relationship with thermodynamics. To make a memory cell crystallize or amorphize by injecting and removing thermal energy as a repetitive memory cycle results in the generation of entropy. In the study and development of PCRAM, the entropic part in the total energy has been neglected in the thermo‐dynamical system. In this paper, we discuss entropic energy losses through simple calculations based on the Sackur–Tetrode equation and compare the results with those obtained by first‐principles computer simulations. In addition, using a structure specific entropy generation model, we verify how much input energy is wasted in phase‐change memory cells fabricated with a Ge2Sb2Te5 alloy‐layer or a simulation optimized [(GeTe)2(Sb2Te3)4]7 multilayer structure. According to a detailed analysis, the entropy derived from application of the Sackur–Tetrode equation is in good agreement with results derived from first‐principles simulations. Our experimental device fabricated using an entropy‐controlled phase‐change design resulted in significant efficiency improvements. Relative to a Ge2Sb2Te5 alloy‐layer device, the new multilayer device exhibited a 82% improvement in energy efficiency for a transition from the high‐ to the low‐resistivity state and with a 64% improvement in efficiency for a transition from the low‐ to the high‐resistivity state. This new entropic‐energy‐loss optimized device was able to return to the high‐resistivity state at approximately the same current as that required for the low‐resistivity state of the alloy device.
Stanford R. Ovshinsky – A sketch
Authors: Fritzsche Hellmut
Published: October 2012

Some path breaking inventions of Stan Ovshinsky that benefitted society will be described. His electrical phase change memories are entering the market, poised to be used in many devices. His optical phase change memories are used in rewritable digital video discs. His pioneering work in thin film electronics led to flexible and light solar panels. His Nickel‐metal hydride batteries are the enabling batteries for hybrid and electric vehicles. His new alloys allow safe and efficient transport, storage, and release of hydrogen, satisfying the needs of a future hydrogen economy. His work has opened non‐crystalline semiconductors as a new field of material science.
Phase change materials: Chalcogenides with remarkable properties due to an unconventional bonding mechanism
Authors: Wuttig Matthias
Published: October 2012

Phase change materials are characterized by a unique property combination which encompasses a pronounced property contrast between the amorphous and crystalline state, as well as rapid crystallization. This property portfolio is ideally suited for data storage applications. In this paper, the understanding of the relationship between the properties of phase change materials and their mechanism of chemical bonding will be reviewed in an attempt to provide a generic explanation for many of the unconventional properties of phase change materials.
Sample size calculation for recurrent events data in one‐arm studies
Authors: Rebora Paola , Galimberti Stefania
Published: October 2012

In some exceptional circumstances, as in very rare diseases, nonrandomized one‐arm trials are the sole source of evidence to demonstrate efficacy and safety of a new treatment. The design of such studies needs a sound methodological approach in order to provide reliable information, and the determination of the appropriate sample size still represents a critical step of this planning process. As, to our knowledge, no method exists for sample size calculation in one‐arm trials with a recurrent event endpoint, we propose here a closed sample size formula. It is derived assuming a mixed Poisson process, and it is based on the asymptotic distribution of the one‐sample robust nonparametric test recently developed for the analysis of recurrent events data. The validity of this formula in managing a situation with heterogeneity of event rates, both in time and between patients, and time‐varying treatment effect was demonstrated with exhaustive simulation studies. Moreover, although the method requires the specification of a process for events generation, it seems to be robust under erroneous definition of this process, provided that the number of events at the end of the study is similar to the one assumed in the planning phase. The motivating clinical context is represented by a nonrandomized one‐arm study on gene therapy in a very rare immunodeficiency in children (ADA‐SCID), where a major endpoint is the recurrence of severe infections. Copyright © 2012 John Wiley & Sons, Ltd.
The analysis of social network data: an exciting frontier for statisticians
Authors: O'Malley A. James
Published: October 2012

The catalyst for this paper is the recent interest in the relationship between social networks and an individual's health, which has arisen following a series of papers by Nicholas Christakis and James Fowler on person‐ to‐person spread of health behaviors. In this issue, they provide a detailed explanation of their methods that offers insights, justifications, and responses to criticisms [1]. In this paper, we introduce some of the key statistical methods used in social network analysis and indicate where those used by Christakis and Fowler (CF) fit into the general framework. The intent is to provide the background necessary for readers to be able to make their own evaluation of the work by CF and understand the challenges of research involving social networks. We entertain possible solutions to some of the difficulties encountered in accounting for confounding effects in analyses of peer effects and provide comments on the contributions of CF. Copyright © 2012 John Wiley & Sons, Ltd.
On the choice of doses for phase III clinical trials
Authors: Lisovskaja Vera , Burman Carl‐Fredrik
Published: October 2012

Many potential new medicines fail in phase III clinical trials, because of either insufficient efficacy or intolerability. Such failures may be caused by the absence of an effect and also if a suboptimal dose is being tested. It is thus important to consider how to optimise the choice of dose or doses that continue into the confirmatory phase. For many indications, it is common to test one single active dose in phase III. However, phase IIB dose‐finding trials are relatively small and often lack the ability of precisely estimating the dose–response curves for efficacy and tolerability. Because of this uncertainty in dose response, it is reasonable to consider bringing more than one dose into phase III. Using simple but illustrative models, we find the optimal doses and compare the probability of success, for fixed total sample sizes, when one or two active doses are included in phase III. Copyright © 2012 John Wiley & Sons, Ltd.
A Path Analysis of the Variables Related to the Quality of Life of Mothers with Disabled Children in Korea
Authors: Cho Kyung Seu , Hong Eun Joo
Published: October 2012

This study examines how different variables affect the quality of life of mothers of children with disabilities. We attempted to identify the relationship between child variables (age and whether the child has single or multiple disabilities), economic variables (monthly income and average monthly treatment cost), mother‐related variables (parenting stress) and social variables (social support) as predictors of the quality of life of mothers of children with disabilities, and the path along which these variables affect their quality of life. The dataset comprised 160 mothers of children with disabilities, who resided in Seoul city and Gyeonggi province. The participants answered questions related to their general information, quality of life, social support and parenting stress. The data were analysed using SPSS 17.0 and AMOS 16.0. We found that social support not only influences the quality of life through parenting stress but also is a direct factor. We also found that both whether a child had single or multiple disabilities and the average monthly treatment cost were significant factors that influenced the parent's quality of life indirectly through parenting stress. Moreover, we concluded that whereas the age of children with disabilities is only a direct impact on the mother's quality of life, monthly income has a direct influence on both parenting stress and quality of life separately, but it does not directly influence quality of life through parenting stress. In our opinion, this is the first study that has conducted a holistic analysis of the quality of life of Korean mothers of children with disabilities by considering a range of variables. Copyright © 2012 John Wiley & Sons, Ltd.
Maternal racial origin and adverse pregnancy outcome: a cohort study
Authors: Khalil A. , Rezende J. , Akolekar R. , Syngelaki A. , Nicolaides K. H.
Published: October 2012

Objective

To examine the association between maternal racial origin and a wide range of adverse pregnancy outcomes after adjustment for confounding factors in obstetric history and maternal characteristics.

Methods

This was a retrospective study in women with singleton pregnancies attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks of gestation. Data on maternal characteristics, and medical and obstetric history were collected and pregnancy outcomes ascertained. Regression analysis was performed to examine the association between racial origin and adverse pregnancy outcomes including pre‐eclampsia (PE), gestational hypertension (GH), gestational diabetes mellitus (GDM), preterm delivery (PTD), small‐for‐gestational age (SGA), large‐for‐gestational age (LGA), miscarriage, stillbirth and elective and emergency Cesarean section (CS).

Results

The study population included 76 158 singleton pregnancies with a live fetus at 11 + 0 to 13 + 6 weeks. In addition to maternal characteristics and obstetric history, Afro‐Caribbean racial origin was associated with increased risk for miscarriage, stillbirth, PE, GH, spontaneous PTD, GDM, SGA and CS. In women of South Asian racial origin there was increased risk for PE, GDM, SGA and CS, and East Asian race contributed to the prediction of GDM and SGA.

Conclusion

Maternal racial origin should be combined with other maternal characteristics and obstetric history when calculating an individualized adjusted risk for adverse pregnancy outcome. Copyright © 2012 ISUOG. Published by John Wiley & Sons, Ltd.
Counseling in fetal medicine: agenesis of the corpus callosum
Authors: Santo S. , D'Antonio F. , Homfray T. , Rich P. , Pilu G. , Bhide A. , Thilaganathan B. , Papageorghiou A. T.
Published: October 2012

In this Review, we aim to provide up‐to‐date and evidence‐based answers to common questions regarding the diagnosis and prognosis of prenatally detected agenesis of the corpus callosum (ACC). A systematic literature search was performed to identify all reports of ACC and reference lists of articles were identified. ACC involves partial or complete absence of the main commissural pathway that connects the two cerebral hemispheres, and can be isolated (with no other abnormalities) or complex (coexisting with other abnormalities). It is a rare finding and the prevalence is difficult to estimate because of selection bias in reported series. The corpus callosum (CC) can be assessed on ultrasound by direct visualization, but indirect features, such as ventriculomegaly, absence of the cavum septi pellucidi or widening of interhemispheric fissure, are often the reason for detection in a screening population. Careful imaging in a center with a high level of expertise is required to make a full assessment and to exclude coexisting abnormalities, which occur in about 46% of fetuses. When available, magnetic resonance imaging appears to be an important adjunct as it allows direct visualization. It can reduce false‐positive rates on ultrasound and can confirm ACC, it can assess whether this is complete or partial and it can help in detecting coexisting brain abnormalities not seen on ultrasound. The overall rate of chromosomal abnormality in fetuses with ACC is 18%, but this high rate includes both isolated and complex ACC; more recent studies suggest that chromosomal abnormalities are rare in isolated cases. Nevertheless, postnatal follow‐up studies suggest that about 15% of cases thought to be isolated prenatally were found to have associated abnormalities after birth. Neurodevelopmental outcome in isolated ACC was recently reported in a systematic review and suggested normal outcome in about 65–75% of cases. Findings need to be considered in light of the several limitations of existing studies, in terms of study design, selection bias, varying definitions and imaging protocols, ascertainment bias and lack of control groups. These uncertainties mean that antenatal counseling is difficult and further large prospective studies are needed.
Parameters of heavy quark effective theory from N
f = 2 lattice QCD
Authors: Blossier Benoît , Della Morte Michele , Fritzsch Patrick , Garron Nicolas , Heitger Jochen , Simma Hubert , Sommer Rainer , Tantalo Nazario
Published: October 2012

Abstract

We report on a non-perturbative determination of the parameters of the lattice Heavy Quark Effective Theory (HQET) Lagrangian and of the time component of the heavy-light axial-vector current with N
f = 2 flavors of massless dynamical quarks. The effective theory is considered at the 1/m
h order, and the heavy mass m
h covers a range from slightly above the charm to beyond the beauty region. These HQET parameters are needed to compute, for example, the b-quark mass, the heavy-light spectrum and decay constants in the static approximation and to order 1/m
h in HQET. The determination of the parameters is done non-perturbatively. The computation reported in this paper uses the plaquette gauge action and two different static actions for the heavy quark described by HQET. For the light-quark action we choose non-perturbatively O(a)-improved Wilson fermions.
Use of a Transanal Drainage Tube for Prevention of Anastomotic Leakage and Bleeding after Anterior Resection for Rectal Cancer
Authors: Zhao Wen‐Tao , Hu Feng‐Liang , Li Yu‐Ying , Li Hong‐Jie , Luo Wei‐Ming , Sun Feng
Published: October 2012

Background

The aim of the present study was to investigate the usefulness of the transanal drainage tube for prevention of anastomotic leakage and bleeding after anterior resection for rectal cancer.

Methods

Between January 2007 and May 2011 a nonrandomized prospective study of patients undergoing anterior resection for rectal cancer was done. The patients were divided into the transanal drainage tube (TDT) and non‐transanal drainage tube (NTDT) groups according to whether the transanal drainage tube was used in the operation. Clinical characteristics and postoperative complications were compared between the TDT and NTDT groups.

Results

The study included 81 patients in the TDT group and 77 patients in the NTDT group. In the TDT group, anastomotic leakage occurred in 2 patients and no anastomotic bleeding occurred. In the NTDT group, anastomotic leakage occurred in 7 patients and anastomotic bleeding occurred in 2 patients. The TDT group had significantly fewer anastomotic complications compared with the NTDT group (2.5 vs 11.7 %; P = 0.029). Furthermore, the TDT group showed an obvious reduction in the rate of anastomotic leakage and anastomotic bleeding compared with the NTDT group (2.5 vs 7.8 % and 0.0 vs 2.6 %), but because the number of cases is relatively small, the difference did not reach statistical significance (P = 0.160 and P = 0.236).

Conclusions

The use of a transanal drainage tube in anterior resection for rectal cancer may be a simple, safe, and effective means of preventing or reducing the occurrence of anastomotic leakage and bleeding. A larger‐scale single or multi‐center prospective randomized study or a meta‐analysis including similar studies is necessary for further elucidation of this issue.
Image and Pathological Changes after Radiofrequency Ablation of Invasive Breast Cancer: A Pilot Study of Nonsurgical Therapy of Early Breast Cancer
Authors: Yoshinaga Yasuteru , Enomoto Yasuko , Fujimitsu Ritsuko , Shimakura Mikiko , Nabeshima Kazuki , Iwasaki Akinori
Published: October 2012

Background

The surgical treatment of early breast cancer has proceeded to less invasive approaches with better cosmetic results. The current study was undertaken to evaluate the clinical and pathological findings after radiofrequency ablation (RFA) without resection for a longer period of time.

Method

A total of 14 patients with breast cancer were enrolled. All patients were diagnosed to have invasive ductal carcinoma, and the median breast tumor size was 12 mm (range, 6–20 mm). Six patients received RFA treatment followed by immediate resection and eight patients without resection. The patients without resection were evaluated by ultrasound, MRI, and the pathological findings of a core needle biopsy after RFA. The removed specimens were examined by hematoxylin‐eosin (HE) staining and nicotinamide adenine dinucleotide (NADH) diaphorase staining. The median follow‐up of the patients was 39.9 months.

Results

NADH staining was necessary to diagnose complete tumor cell death in the tissue for 3 months after RFA. However, HE staining alone could confirm the effect without NADH staining more than 6 months after RFA. Post‐RFA, MRI scans clearly demonstrated the area as a complete ablated lesion in all patients without resection. The ablated area detected by MRI or ultrasound became gradually smaller. All patients that underwent RFA with no resection were alive without relapse.

Conclusion

RFA therefore could be an effective alternative to partial mastectomy for early breast cancer. Further research will be necessary to establish the standardization of the indications, as well as the optimal techniques and post treatment evaluation modalities.
Evaluation of Dysphagia and Diminished Airway Protection after Three‐Field Esophagectomy and a Remedy
Authors: Yasuda Takushi , Yano Masahiko , Miyata Hiroshi , Yamasaki Makoto , Takiguchi Shuji , Fujiwara Yoshiyuki , Doki Yuichiro
Published: October 2012

Background

Recently, reports from the West have indicated three‐field lymphadenectomy (3FL) for esophageal cancer increases the accuracy of tumor staging and survival. However, this cervical procedure is likely to lead to swallowing dysfunction and aspiration, which are barriers to introducing this procedure in clinical practice.

Methods

Our goal is to elucidate the etiology of swallowing dysfunction after 3FL and devise a remedy. First, based on evaluation of swallowing function in ten patients with two‐field lymphadenectomy (2FL) and ten with 3FL, we hypothesized that the scarred sternohyoid and sternothyroid muscles might be impairing laryngeal elevation after 3FL; thus, complete division of the bilateral infrahyoid muscles attached to the sternum (CDBIMS) could be an effective remedy. Next, the utility of this additive procedure was examined in 20 patients with 3FL. Swallowing function was evaluated by the distance of total laryngeal elevation (TLE) and the frequency of incomplete airway protection (IAP) (laryngeal penetration or aspiration) on videofluoroscopic study.

Results

The average TLE and frequency of IAP were, respectively, 0.37 cm and 70 % in the 3FL group, showing significant deterioration (p < 0.001 and 0.025), in contrast to 1.79 cm and 20 % in the 2FL group. The 3FL + CDBIMS group showed significant improvements in the average TLE and the frequency of IAP (1.70 cm and 25 %), compared with the 3FL group (p < 0.001 and 0.018). Multivariate logistic regression identified additive CDBIMS as a significant suppressor of IAP after 3FL.

Conclusions

Laryngeal elevation was significantly impaired after 3FL. Adding CDBIMS might improve swallowing function in these patients.
Home‐field advantage in decomposition of leaf litter and insect frass
Authors: Kagata Hideki , Ohgushi Takayuki
Published: October 2012

Home‐field advantage (HFA) hypothesis regarding litter decomposition states that litter is decomposed more rapidly in the habitat from which it is derived (i.e., home) than in other habitat (i.e., away) due to local adaptation of soil decomposers. We tested the HFA hypothesis regarding decomposition of leaf litter, insect frass, and their mixtures, using laboratory incubation of leaf litter from an evergreen (Pinus densiflora) and a deciduous (Quercus acutissima) tree species, frass excreted by two insect herbivores (Dendrolimus spectabilis and Lymantria dispar) fed on one of the two trees, and soil collected underneath the two trees. We found evidence that decomposers in each soil were specialized to decompose the litter derived from the tree species above them, indicating that the HFA occurred in litter decomposition. In contrast, the HFA was not detected in the decomposition of insect frass or litter‐frass mixtures. Mixing with D. spectabilis frass non‐additively decelerated, while mixing with L. dispar frass non‐additively accelerated, decomposition of the mixtures, independent of soil and litter types. These indicate that the presence of insect herbivores may make it difficult to form and maintain a decomposer community specialized to a certain leaf litter, and that it may consequently cancel or weaken HFA in litter decomposition.
Production of organic acids by periplasmic enzymes present in free and immobilized cells of Zymomonas mobilis
Authors: Malvessi Eloane , Carra Sabrina , Pasquali Flávia Cristina , Kern Denise Bizarro , da Silveira Mauricio Moura , Ayub Marco Antônio Záchia
Published: October 2012

In this work the periplasmic enzymatic complex glucose-fructose oxidoreductase (GFOR)/glucono-δ-lactonase (GL) of permeabilized free or immobilized cells of Zymomonas mobilis was evaluated for the bioconversion of mixtures of fructose and different aldoses into organic acids. For all tested pairs of substrates with permeabilized free-cells, the best enzymatic activities were obtained in reactions with pH around 6.4 and temperatures ranging from 39 to 45 °C. Decreasing enzyme/substrate affinities were observed when fructose was in the mixture with glucose, maltose, galactose, and lactose, in this order. In bioconversion runs with 0.7 mol l−1 of fructose and with aldose, with permeabilized free-cells of Z. mobilis, maximal concentrations of the respective aldonic acids of 0.64, 0.57, 0.51, and 0.51 mol l−1 were achieved, with conversion yields of 95, 88, 78, and 78 %, respectively. Due to the important applications of lactobionic acid, the formation of this substance by the enzymatic GFOR/GL complex in Ca-alginate-immobilized cells was assessed. The highest GFOR/GL activities were found at pH 7.0–8.0 and temperatures of 47–50 °C. However, when a 24 h bioconversion run was carried out, it was observed that a combination of pH 6.4 and temperature of 47 °C led to the best results. In this case, despite the fact that Ca-alginate acts as a barrier for the diffusion of substrates and products, maximal lactobionic acid concentration, conversion yields and specific productivity similar to those obtained with permeabilized free-cells were achieved.
Extracting Intrinsic Functional Networks with Feature-Based Group Independent Component Analysis
Authors: Calhoun Vince D. , Allen Elena
Published: October 2012

There is increasing use of functional imaging data to understand the macro-connectome of the human brain. Of particular interest is the structure and function of intrinsic networks (regions exhibiting temporally coherent activity both at rest and while a task is being performed), which account for a significant portion of the variance in functional MRI data. While networks are typically estimated based on the temporal similarity between regions (based on temporal correlation, clustering methods, or independent component analysis [ICA]), some recent work has suggested that these intrinsic networks can be extracted from the inter-subject covariation among highly distilled features, such as amplitude maps reflecting regions modulated by a task or even coordinates extracted from large meta analytic studies. In this paper our goal was to explicitly compare the networks obtained from a first-level ICA (ICA on the spatio-temporal functional magnetic resonance imaging (fMRI) data) to those from a second-level ICA (i.e., ICA on computed features rather than on the first-level fMRI data). Convergent results from simulations, task-fMRI data, and rest-fMRI data show that the second-level analysis is slightly noisier than the first-level analysis but yields strikingly similar patterns of intrinsic networks (spatial correlations as high as 0.85 for task data and 0.65 for rest data, well above the empirical null) and also preserves the relationship of these networks with other variables such as age (for example, default mode network regions tended to show decreased low frequency power for first-level analyses and decreased loading parameters for second-level analyses). In addition, the best-estimated second-level results are those which are the most strongly reflected in the input feature. In summary, the use of feature-based ICA appears to be a valid tool for extracting intrinsic networks. We believe it will become a useful and important approach in the study of the macro-connectome, particularly in the context of data fusion.
Odor Significance of the Volatiles Formed During Deep‐Frying With Palm Olein
Authors: Osawa C. C. , Gonçalves L. A. G. , Da Silva M. A. A. P.
Published: October 2012

Palm olein is currently considered to be one of the best options for deep‐frying, but as with any other edible oil, during frying, deteriorative reactions produce off‐flavor compounds that reduce the oil sensory quality. This study assessed the odor significance of the volatiles formed during 136 h of deep‐frying a chicken product in palm olein, aiming to identify potential markers of the oil sensory quality during frying. The volatiles were isolated by solid phase microextraction, and identified by GC–MS. Trained judges assessed the odor intensity and quality of the volatiles formed during frying, evaluating the GC effluents through a GC–olfactometry technique called OSME. Two hundred and eight volatiles were detected by GC/MS in the palm olein after 136 h frying. Of these, heptanal, t‐2‐heptenal, decanal and t‐2‐undecenal were identified as potential markers of the sensory quality of palm olein during frying. Hexanal, pentanal and pentane, usually associated with lipid oxidation, showed no odor impact in the GC effluents, and were thus proven not to be good markers of the sensory quality of palm olein when used for a long frying period.
Adult Mortality From Sibling Survival Data: A Reappraisal of Selection Biases
Authors: Masquelier Bruno
Published: October 2012

Because of incomplete registration of deaths in most countries in sub-Saharan Africa, data on the survival of close relatives constitute the cornerstone of estimates of adult mortality. Since 1990, sibling histories have been widely collected in Demographic and Health Surveys and are increasingly being relied upon to estimate both general and maternal mortality. Until recently, the use of sibling histories was thought to lead to underestimates of mortality, but a more optimistic view in the literature emerged with the development by Gakidou and King (Demography 43:569–585, 2006) of corrections for selection biases. Based on microsimulations, this article shows that Gakidou and King’s weighting scheme has been incorrectly applied to survey data, leading to overestimates of mortality, especially for males. The evidence for an association between mortality and sibship size in adulthood is reviewed. Female mortality appears to decline slightly with the number of surviving sisters, although this could be an artifact of severe recall errors in larger sibships or familial clustering of deaths. Under most circumstances, corrections for selection biases should have only a modest effect on sibling estimates.