bluuebunny/crossref_metadata_2025 huggingface dataset:
A Coupled Method of Spectral Element and Normal Mode: A Powerful Tool for Modeling the Seismic Waves Propagation in the Anisotropic D″ Region
Authors: Ming ZHAO , Liang ZHAO , CAPDEVILLE YANN
Published: June 2013

We extended the coupled mode/spectral element method (CSEM hereafter) to incorporate three‐dimensional, anisotropic media in the lowest 300 km above the core‐mantle boundary, the D″ area. This extended method was applied to modeling of seismic waves propagation in earth models under the so‐called “sandwich” structure, which uses a spherical shell of spectral elements between two modal solutions to represent the D″ area. Using a spherically symmetric reference model with modified anisotropic parameters in the spherical shell, the CSEM yields waveforms in excellent agreement with that of normal‐mode. The two methods match very well for all body wave arrivals with periods greater than 8 s. Besides, the S, ScS, SKS, and SKKS phases in the synthetic seismograms of the transverse isotropic model show obvious arrival time differences between SH and SV components. This proves the capability of the extended CSEM code for modeling S wave splitting caused by the radial anisotropic media in the D″ area.
Presence of Angina Pectoris Is Related to Extensive Coronary Artery Disease in Diabetic Patients
Authors: Celik Atac , Karayakali Metin , Erkorkmaz Unal , Altunkas Fatih , Karaman Kayihan , Koc Fatih , Ceyhan Koksal , Kadi Hasan , Avsar Alaettin
Published: June 2013

Background

Due to sensorial autonomic neuropathy, the type and severity of angina pectoris in patients with diabetes mellitus (DM) may be rather different from the type and severity of angina pectoris in patients without DM.

Hypothesis

The aim of the study was to understand if angina pectoris is related to extensive coronary artery disease (CAD) in patients with DM.

Methods

The study included 530 patients with DM who underwent coronary angiography at our center in 2009 and 2010. Patients were divided into 4 groups according to type of chest pain: group 1, noncardiac chest pain or no pain; group 2, angina equivalent; group 3, atypical angina; and group 4, typical angina. All angiograms were re‐evaluated and Gensini scores were calculated. Three‐vessel disease was diagnosed in the presence of stenosis >50% in all 3 coronary artery systems.

Results

There were no statistically significant differences between the groups with regard to age, sex, systolic or diastolic blood pressures, body mass index, creatinine clearance, or lipid profile. Fasting blood glucose was significantly higher in group 4 than in group 2. Gensini scores were not statistically different between groups 1 and 2 or between groups 3 and 4; however, the scores for groups 3 and 4 were higher than the score for either group 1 or group 2. Prevalence of 3‐vessel disease was significantly higher in groups 3 and 4 compared with the other groups.

Conclusions

The presence of angina pectoris was related to extensive CAD in patients with DM. The extent of CAD was not correlated with the type of angina (typical or atypical).
Threshold‐based context analysis approach for ubiquitous systems
Authors: Khabou Nesrine , Rodriguez Ismael Bouassida
Published: June 2013

In ubiquitous computing environments, applications must be able to respond to dynamic context changes in order to provide suitable services to users. A promising solution consists of developing context aware applications. In this paper, we present an approach that supports context awareness in a ubiquitous computing environment. The proposed approach focuses on handling context information including context monitoring/acquisition, context interpretation, context classification, context storage, context analysis, and context aware adaptation. In this paper, we focus on context classification and context analysis. We present a context classification approach, which takes into account the context parameter evolution behavior. Then, we define a context analysis approach for ubiquitous computing environments. The proposed analysis approach aims at analyzing contextual information and detecting significant changes. The proposed analysis approach uses a threshold comparison technique in order to detect context changes. When relevant context changes are detected, the context aware application will be notified to trigger its suitable process dynamically in order to deal with the changes. Copyright © 2013 John Wiley & Sons, Ltd.
Heavy Atom Effect Driven Organic Phosphors and Their Luminescent Lanthanide Metal–Organic Frameworks
Authors: Balamurugan Ayyakkalai , Gupta Arvind Kumar , Boomishankar Ramamoorthy , Lakshmipathi Reddy Mundlapudi , Jayakannan Manickam
Published: June 2013

This investigation demonstrates the heavy atom effect (HAE) concept in developing new organic phosphors and engineering the excited‐state energy levels in lanthanide metal ion suprastructures. This was accomplished by coupling two independent energy‐transfer photophysical processes: enhancing the electronic population in the excited triplet state through intersystem crossing (ISC) and transferring the triplet energy to the excited state of the lanthanide ions. A new series of iodo‐substituted carboxylic ligands were synthesised through a tailor‐made approach and complexes with Eu3+ ions to give one‐ and three‐dimensional metal–organic frameworks (MOFs). Single‐crystal structures of the europium complexes revealed the formation of a 1D linear coordination polymer for the monocarboxylate ligand and 3D MOFs for the dicarboxylate ligand. The HAE quenches the S1→S0 transition (self‐fluorescence) in these ligands and promotes S1→T processes for building enhanced excited triplet electronic states. Single‐crystal structures of iodo‐substituted complexes proved that the ligand molecules were held together by strong π stacking. The π stack restricted vibration relaxation and, as a result, these ligands turned into white or yellowish solid‐state organic phosphors. In Eu3+ ion complexes, the solid‐state phosphorescence of the ligands was completely quenched and the triplet excitation energy was channelled into ligand‐to‐metal energy transfer. Thus, the current approach opens up a new strategy for designing luminescent MOFs based on the HAE principle by controlling the excited‐state energy levels.
Identification of a widespread Kamchatkan tephra: A middle Pleistocene tie‐point between Arctic and Pacific paleoclimatic records
Authors: Ponomareva Vera , Portnyagin Maxim , Derkachev Alexander , Juschus Olaf , Garbe‐Schönberg Dieter , Nürnberg Dirk
Published: June 2013

Very few age controls exist for Quaternary deposits over the vast territory of the East Russian Arctic, which hampers dating of major environmental changes in this area and prevents their correlation to climatic changes in the Arctic and Pacific marine domains. We report a newly identified ~177 ka old Rauchua tephra, which has been dispersed over an area of >1,500,000 km2 and directly links terrestrial paleoenvironmental archives from Arctic Siberia with marine cores in the northwest Pacific, thus permitting their synchronization and dating. The Rauchua tephra can help to identify deposits formed in terrestrial and marine environments during the oxygen isotope stage 6.5 warming event. Chemical composition of volcanic glass from the Rauchua tephra points to its island‐arc origin, while its spatial distribution singles out the Kamchatka volcanic arc as a source. The Rauchua tephra represents a previously unknown, large (magnitude >6.5) explosive eruption from the Kamchatka volcanic arc.
Statistically downscaled projections of snow/rain partitioning for Alaska
Authors: McAfee Stephanie A. , Walsh John , Rupp T. Scott
Published: June 2013

Adaptation planning in Alaska, as in other snowy parts of the world, will require snow projections, yet snow is a challenging variable to measure, simulate and downscale. Here we describe the construction and evaluation of 771‐m‐resolution gridded historical and statistically downscaled projections of snow/rain partitioning for the state of Alaska at decadal temporal resolution. The method developed here uses observational data to describe the relationship between average monthly temperature and the fraction of wet days in that month receiving snow, the snow‐day fraction. Regionally and seasonally specific equations were developed to accommodate variability in synoptic scale climatology of rain and snow events. These equations were then applied to gridded decadal temperature data and projections. The gridded products provide a reasonable characterization of snow‐day fraction throughout the state. However, there are local deviations from the regional relationships, particularly in the topographically complex areas ringing the Gulf of Alaska and Cook Inlet. When applied to questions about changing precipitation regimes in northern, western and south‐eastern Alaska, these data demonstrate the potential for marked changes from snow‐dominated to mixed precipitation regimes and also exhibit a wide range of potential future conditions. Copyright © 2013 John Wiley & Sons, Ltd.
Current Challenges in Nucleic Acid Synthesis
Authors: Hogrefe Richard I. , Midthune Brea , Lebedev Alexandre
Published: June 2013

Our understanding of the role of nucleic acids in regulating the process of life is growing rapidly. As researchers delve deeper into the cellular activity of molecules such as microRNA, small interfering RNA, and long non‐coding RNA, the oligonucleotide chemist is confronted with the challenge of synthesizing the tools needed to continue this work. Furthermore, new applications are being developed that require increasingly complicated oligonucleotide constructs. In this review, we explore the current challenges confronting oligonucleotide synthesis, describe the chemistry and the enzymology being developed in response to those challenges, and discuss future challenges as‐yet unmet.
Dose‐dependent alterations in gene expression and testosterone production in fetal rat testis after exposure to di‐n‐hexyl phthalate
Authors: Saillenfait Anne‐Marie , Sabaté Jean‐Philippe , Robert Alain , Rouiller‐Fabre Virginie , Roudot Alain‐Claude , Moison Delphine , Denis Flavien
Published: June 2013

In utero exposure to the phthalate ester plasticizer di‐n‐hexyl phthalate (DnHP) is known to affect the development of the male reproductive system and induce alterations in androgen‐dependent tissues of male rat offspring. Male reproductive malformations produced by several phthalates have been causally linked to decreased testosterone production during the gestational period. This study was designed to evaluate the dose–response relationship for the effects of DnHP on the synthesis and production of testosterone in the fetal rat testis. Pregnant Sprague–Dawley rats were administered the vehicle (olive oil) and either DnHP (5 to 625 mg kg–1 per day) or diethylhexyl phthalate (DEHP) (50 or 625 mg kg–1 per day), by gavage, from gestation day (GD) 12 to19. Fetal testes were assessed on GD 19. DnHP reduced ex vivo testosterone production and down‐regulated the expression of several genes required for cholesterol transport and steroid synthesis (i.e. SR‐B1, StAR, P450scc, 3βHSD and P450c17). These inhibitions were dose dependent. A no‐effect level was established at 5 mg kg–1 per day and a lowest‐effect level at 20 mg kg–1 per day. mRNA levels of SR‐B1, StAR, P450scc and 3βHSD were not similarly decreased in the adrenals. In conclusion, DnHP shares the same mode of action as DEHP in disrupting fetal testicular androgen synthesis. Alterations in testosterone production and in key steroidogenic gene expressions were apparent at lower doses than those causing postnatal reproductive malformations after gestational exposure during the critical period of male sexual differentiation. This suggests that they can be considered early biomarkers of DnHP‐induced fetal testicular effects in rats. Copyright © 2013 John Wiley & Sons, Ltd.
Characterization of the allergenic potential of proteins: an assessment of the kiwifruit allergen actinidin
Authors: Dearman Rebecca J. , Beresford Lorna , Foster Emily S. , McClain Scott , Kimber Ian
Published: June 2013

Assessment of the potential allergenicity (IgE‐inducing properties) of novel proteins is an important challenge in the overall safety assessment of foods. Resistance to digestion with pepsin is commonly measured to characterize allergenicity, although the association is not absolute. We have previously shown that specific IgE antibody production induced by systemic [intraperitoneal (i.p.)] exposure of BALB/c strain mice to a range of proteins correlates with allergenic potential for known allergens. The purpose of the present study was to explore further the utility of these approaches using the food allergen, actinidin. Recently, kiwifruit has become an important allergenic foodstuff, coincident with its increased consumption, particularly as a weaning food. The ability of the kiwifruit allergen actinidin to stimulate antibody responses has been compared with the reference allergen ovalbumin, and with the non‐allergen bovine haemoglobin. Haemoglobin was rapidly digested by pepsin whereas actinidin was resistant unless subjected to prior chemical reduction (reflecting intracellular digestion conditions). Haemoglobin stimulated detectable IgG antibody production at relatively high doses (10%), but failed to provoke detectable IgE. In contrast, actinidin was both immunogenic and allergenic at relatively low doses (0.25% to 1%). Vigorous IgG and IgG1 antibody and high titre IgE antibody responses were recorded, similar to those provoked by ovalbumin. Thus, actinidin displays a marked ability to provoke IgE, consistent with allergenic potential. These data provide further encouragement that in tandem with analysis of pepsin stability, the induction of IgE after systemic exposure of BALB/c strain mice provides a useful approach for the prospective identification of protein allergens. Copyright © 2013 John Wiley & Sons, Ltd.
Effect of Juvenoids on Predator‐Induced Polyphenism in the Water Flea, Daphnia pulex
Authors: Miyakawa Hitoshi , Gotoh Hiroki , Sugimoto Naoki , Miura Toru
Published: June 2013

In Daphnia pulex, juveniles form “neckteeth” a defensive structure on their heads, in response to predatory kairomones released by Chaoborus larvae. This phenomenon provides a model experimental system for the study of developmental mechanisms and evolutionary processes in predator‐induced polyphenisms. Although it is thought that kairomone signals are sensed and converted into physiological signals resulting in morphological changes, little is known about the endocrine and physiological mechanisms of this process. Juvenile hormones and related chemicals, that is, juvenoids, are key hormones responsible for various physiological events in insects, including polyphenisms. In some crustaceans, methyl farnesoate (MF) is known to act as a juvenoid. In order to investigate the functions of juvenoids in defense morph formation, we treated daphnids with MF as well as JHIII (Juvenile Hormone III, an insect juvenoid) and fenoxycarb (a synthetic juvenile hormone analog) during their developmental stages. Strikingly, in the first‐instar juveniles, all examined juvenoids stimulated the formation of neckteeth only in the presence of kairomones, not by themselves. This juvenoid effect on the neckteeth formation might be due to disturbance of the JH pathway. Juvenoid treatments reduced tail‐spine length, whereas predatory kairomones are known to elongate tail spine. These results suggest that other physiological factors are responsible for the tail‐spine elongation. J. Exp. Zool. 319A: 440–450, 2013. © 2013 Wiley Periodicals, Inc.
Early India‐Australia spreading history revealed by newly detected Mesozoic magnetic anomalies in the Perth Abyssal Plain
Authors: Williams Simon E. , Whittaker Joanne M. , Granot Roi , Müller Dietmar R.
Published: June 2013

The seafloor within the Perth Abyssal Plain (PAP), offshore Western Australia, is the only section of crust that directly records the early spreading history between India and Australia during the Mesozoic breakup of Gondwana. However, this early spreading has been poorly constrained due to an absence of data, including marine magnetic anomalies and data constraining the crustal nature of key tectonic features. Here, we present new magnetic anomaly data from the PAP that shows that the crust in the western part of the basin was part of the Indian Plate—the conjugate flank to the oceanic crust immediately offshore the Perth margin, Australia. We identify a sequence of M2 and older anomalies in the west PAP within crust that initially moved with the Indian Plate, formed at intermediate half‐spreading rates (35 mm/yr) consistent with the conjugate sequence on the Australian Plate. More speculatively, we reinterpret the youngest anomalies in the east PAP, finding that the M0‐age crust initially formed on the Indian Plate was transferred to the Australian Plate by a westward jump or propagation of the spreading ridge shortly after M0 time. Samples dredged from the Gulden Draak and Batavia Knolls (at the western edge of the PAP) reveal that these bathymetric features are continental fragments rather than igneous plateaus related to Broken Ridge. These microcontinents rifted away from Australia with Greater India during initial breakup at ~130 Ma, then rifted from India following the cessation of spreading in the PAP (~101–103 Ma).
The 3‐connected graphs with a maximum matching containing precisely one contractible edge
Authors: Aldred R. E. L. , Hemminger Robert L. , Yu Xingxing
Published: June 2013

It has previously been shown that if M is a maximum matching in a 3‐connected graph G, other than K4, then M contains at least one contractible edge of G. In this paper, we give a constructive characterization of the 3‐connected graphs G having a maximum matching containing only one contractible edge of G.
Intersection graphs of proper subtrees of unicyclic graphs
Authors: Gavril Fǎnicǎ
Published: June 2013

A graph is fraternally oriented iff for every three vertices u, ν, w the existence of the edges u → w and ν → w implies that u and ν are adjacent. A directed unicyclic graph is obtained from a unicyclic graph by orienting the unique cycle clockwise and by orienting the appended subtrees from the cycle outwardly. Two directed subtrees s, t of a directed unicyclic graph are proper if their union contains no (directed or undirected) cycle and either they are disjoint or one of them s has its root r(s) in t and contains all the successors of r(s) in t.

In the present paper we prove that G is an intersection graph of a family of proper directed subtrees of a directed unicyclic graph iff it has a fraternal orientation such that for every vertex ν, G(Γinν) is acyclic and G(Γoutν) is the transitive closure of a tree. We describe efficient algorithms for recognizing when such graphs are perfect and for testing isomorphism of proper circular‐arc graphs.
The inducibility of complete bipartite graphs
Authors: Brown Jason I. , Sidorenko Alexander
Published: June 2013

For any s ≥ 1 and t ≥ (S2), we prove that among all graphs with n vertices the graph that contains the maximal number of induced copies of Kt, t+s for any fixed s ≥ 1 and t ≥ (s2) is K(n/2)+α(n/2)‐α for some function α = o(n). We show that this is not valid for t < (s2). Analogous results for complete multipartite graphs are also obtained.
Long‐term results of surgical treatment of vocal fold nodules
Authors: Béquignon Emilie , Bach Christine , Fugain Claude , Guilleré Lia , Blumen Marc , Chabolle Frédéric , Wagner Isabelle
Published: June 2013

Objectives/Hypothesis

To evaluate the long‐term outcome of patients with vocal fold nodules treated by surgery alone, or by a combination of surgery and voice therapy and to identify factors associated with long‐term recurrent dysphonia.

Study Design

Retrospective study.

Methods

All patients who had undergone surgery for vocal fold nodules in a tertiary care hospital between 1996 and 2006 were contacted. After giving their consent, they were evaluated by videostroboscopic examination of vocal fold nodules and by a subjective questionnaire including the Voice Handicap Index (VHI).

Results

Sixty‐two out of 90 patients (69%) (60 women, 2 men with a mean age of 33 years) answered the questionnaire at a mean interval of 9.5 years after surgery. Recurrent dysphonia was observed in 19 patients (30%) at a mean interval of 5.2 years after surgery and new benign vocal fold lesions (nodules or Reinke's edema) were observed in 11 patients (18%). Absence of postoperative voice therapy was significantly associated with a higher recurrence rate (P = 0.02) (56% of recurrent dysphonia without voice therapy versus 22% with voice therapy).

Conclusions

Postoperative voice therapy decreases the risk of recurrence. Vocal fold nodules can recur over a period of 5 years, consequently requiring follow‐up for at least 5 years in clinical practice and in future prospective studies.

Level of Evidence

2b (Individual retrospective cohort study). Laryngoscope, 123:1926–1930, 2013
Cochlear pharmacokinetics of cisplatin: An in vivo study in the guinea pig
Authors: Hellberg Victoria , Wallin Inger , Ehrsson Hans , Laurell Göran
Published: June 2013

Objectives/Hypothesis

Cisplatin produces toxic lesions to outer hair cells (OHCs) in the cochlear base but not in the apex. The objective of this study was to compare the pharmacokinetic profile of cisplatin in scala tympani (ST) perilymph in the cochlear base and apex, respectively.

Study Design

In vivo animal study.

Methods

Forty‐seven guinea pigs were given an intravenous bolus injection of an ototoxic dose of cisplatin. Ten to 240 minutes after cisplatin was given, blood, cerebrospinal fluid (CSF), and ST perilymph were aspirated within the same target time. ST perilymph was aspirated from the basal turn and from the apex of the cochlea by two different sampling techniques. Liquid chromatography with postcolumn derivatization was used for quantitative determination of the parent drug.

Results

Ten minutes after administration, the concentration of cisplatin in ST perilymph was 4‐fold higher in the basal turn of the cochlea than in the apex. At 30 minutes, the drug concentrations did not differ. At 60 minutes, the level of cisplatin in ST perilymph and blood UF was equivalent. The perilymph‐blood ratio increased thereafter with time.

Conclusion

The pharmacokinetic findings of an early high concentration of cisplatin in the base of the cochlea and delayed elimination of cisplatin from ST perilymph compared to blood might correlate to the cisplatin‐induced loss of OHCs in the base of the cochlea.

Level of Evidence

N/A. Laryngoscope, 123:3172–3177, 2013
Trends of human papillomavirus‐related head and neck cancers in Korea: National cancer registry data
Authors: Shin Aesun , Jung Yuh‐S. , Jung Kyu‐Won , Kim Kyeezu , Ryu Junsun , Won Young‐Joo
Published: June 2013

Objectives/Hypothesis

The incidence of human papillomavirus (HPV)‐positive head and neck cancers (HNCs) is increasing sharply worldwide, while their HPV‐negative counterparts are showing a decreased frequency. However, epidemiologic data related to these changes are sparse in Korea, which is rapidly adopting more westernized lifestyles.

Study Design

Data from the Korea Central Cancer Registry, a nationwide population‐based cancer registry, from 1999 to 2009 were retrieved.

Methods

Age‐standardized rates (ASRs), their annual percent changes (APC) and male‐to‐female incidence rate ratios (IRRs) were analyzed and compared between HPV‐related and HPV‐unrelated primary sites.

Results

HPV‐related sites (oropharynx) had increased significantly over the period 1999 to 2009 (APC = 2.35%, P = 0.017), particularly in young men (30–59 years, APC = 2.65%, P = 0.031), whereas HPV‐unrelated sites such as larynx and hypopharynx decreased markedly in both sexes. Interestingly, tongue cancer was found to have increased gradually (APC = 2.35%, P = 0.003) in both sexes. The male‐to‐female IRRs and the median age of occurrence remained stable.

Conclusions

Although the cultural and ethnic background differs from the United States, cancers of HPV‐related sites are increasing in Korea, whereas cancers of HPV‐unrelated sites are decreasing, which is similar to the trends observed in the United States. Greater public awareness in Korea of HPV‐related HNCs is therefore warranted.

Level of Evidence

2b. Laryngoscope, 123:E30–E37, 2013
Leadership Development Personalized!
Authors: Masie Elliott
Published: June 2013

Masie believes that as personalization catches on outside the workplace (from restaurant eating to watching television to e‐commerce), organizational learning will become increasingly personalized. Rather than attending multiday classes, or sitting through long e‐learning modules, people now want to “learn in their own style, focusing on content that is just right for them at that moment in their lives or careers.” He provides a number of examples of this personalization, including transformations of learning spaces, harnessing different models of mentoring, and mixing face‐to‐face and online/virtual formats, with “designs that go far beyond PowerPoint and audio talk‐overs.”
Innovation Starts with a Kill Manifesto
Authors: Bodell Lisa
Published: June 2013

Bodell believes that to plan for its future, a company should see itself through the eyes of its competitors, through a “Kill the Company” exercise. Employees think of ways competitors could put it out of business. Next is to see if threats are clustered in particular areas, such as R&D or customer service. Strategies can be developed to counter these threats, and lead to strategies to be used against the competition. She also advocates “Killer Queries,” open‐ended questions in such areas as pricing, logistics, and trends. For example, “Which emerging trend is most likely to uproot our business model?”
Frustriert, aber äußerst nützlich
Authors: Uhl Werner
Published: June 2013

Frustrierte Lewis‐Paare enthalten Lewis‐saure und ‐basische Atome, ohne dass sich die entgegen‐ gesetzten Funktionalitäten durch Adduktbildung löschen. Die Verbindungen koordinieren und aktivieren kleine Moleküle. Neuere Verbindungen mit Aluminium übertreffen in manchen Eigenschaften die etablierten borhaltigen Substanzen.
Schluss mit dem Ratespiel bei Wasserstoffatomen
Authors: Dittrich Birger
Published: June 2013

Die Metall‐ und Kohlenstoffatome sind lokalisiert, aber die Position der Wasserstoffatome lässt sich mit der Röntgenstrukturanalyse nur ungenau ermitteln. Auch theoretische Berechnungen halfen hier meist nicht weiter. Neue Verfeinerungs‐ und Rechenmethoden können das ändern.
Die Blässe des Cadmiumgelbs
Authors: Ridder Barbara
Published: June 2013

Cadmiumgelb galt Künstlern wie Vincent van Gogh als besonders stabiles und leuchtendes Farbpigment. Im Laufe der Zeit verändert es jedoch seine Farbe. Warum aber verfärben sich die Pigmente in einem Gemälde von van Gogh grau‐orange, während sie in einem Bild von James Ensor nur verblassen?
Robust partitioned block preconditioners for large‐scale geotechnical applications with soil–structure interactions
Authors: Chen Xi , Jie Yuxin , Liu Jiankun
Published: June 2013

Soil–structure interaction problems are commonly encountered in geotechnical practice and remarkably characterized with significant material stiffness contrast. When solving the soil–structure interaction problems, the employed Krylov subspace iterative method may converge slowly or even fail, indicating that the adopted preconditioning method may not suit for such problems. The inexact block diagonal preconditioners proposed recently have been shown effective for the soil–structure interaction problems; however, they haven't been exploited to full capabilities. By using the same partition strategy according to the structure elements and soil elements, the partitioned block symmetric successive over‐relaxation preconditioners or partitioned block constraint preconditioners are proposed. Based on two pile‐group foundation problems and a tunnel problem, the proposed preconditioners are evaluated and compared with the available preconditioners for the consolidation analysis and the drained analysis, respectively. In spite of one additional solve associated with the structure block and multiplications with off‐diagonal blocks in the preconditioning step, numerical results reveal that the proposed preconditioners obviously possess better performance than the recently developed inexact block preconditioners. Copyright © 2013 John Wiley & Sons, Ltd.
Urinary and ejaculatory dysfunction induced by denervation of specific striated muscles anatomically related to the urethra in male rats
Authors: Juárez Raúl , Cruz Yolanda
Published: June 2013

Aims

The purpose of the present study was to determine the contribution of the external urethral sphincter (EUS), the ischiocavernous (IC), or the bulbospongiosus (BS) on the control of micturition, copulatory behavior and semen expulsion in male rats. We hypothesized that the EUS contributes to maintain urinary continence, while all three muscles participate in expulsive urethral functions.

Methods

In Experiment 1, it was analyzed the effects of bilateral denervation of IC, BS or EUS, or sham surgery, on voiding behavior and urinary parameters measured before surgery and 2 and 10 days post‐surgery. In Experiment 2, copulatory behavior and the weight of the seminal plug expelled during ejaculation were recorded before and after sham surgery or bilateral denervation of the aforementioned muscles. Immediately after ejaculation, the animals were anesthetized to confirm the denervation and determine whether seminal material had accumulated in the lower urinary tract.

Results

In IC‐denervated animals, voiding duration and the number of mounts was increased, and intromission or ejaculation patterns were absent. Denervation of BS induced signs of post‐micturition dribble, decreased voiding frequency, increased urine volume and reduced the amount of semen ejaculated. Denervation of EUS induced signs of post‐micturition dribble and urinary incontinence, as well as retrograde ejaculation.

Conclusions

Striated muscles anatomically related to the urethra contribute differentially to the control of continence and expulsive urethral functions. Damages to the muscles or to their innervation, as may occur during pelvic surgery, would result in sexual and urinary dysfunctions. Neurourol. Urodynam. 33:437–442, 2014. © 2013 Wiley Periodicals, Inc.
Thoracic periaortic and visceral adipose tissue and their cross‐sectional associations with measures of vascular function
Authors: Britton Kathryn A. , Wang Na , Palmisano Joseph , Corsini Erin , Schlett Christopher L. , Hoffmann Udo , Larson Martin G. , Vasan Ramachandran S. , Vita Joseph A. , Mitchell Gary F. , Benjamin Emelia J. , Hamburg Naomi M. , Fox Caroline S.
Published: June 2013

Objective: Perivascular fat may have a local adverse effect on the vasculature. We evaluated whether thoracic periaortic adipose tissue (TAT), a type of perivascular fat, and visceral adipose tissue (VAT) were associated with vascular function.

Design and Methods

TAT and VAT were quantified in Framingham Heart Study participants using multidetector‐computed tomography; vascular function was assessed using brachial artery vasodilator function, peripheral arterial tone, and arterial tonometry (n = 2,735; 48% women; mean age, 50 years; mean body mass index [BMI], 27.7 kg/m2). Using multiple linear regression, the relationships between TAT, VAT, and vascular measures was examined while adjusting for cardiovascular risk factors.

Results

Mean TAT and VAT volumes were 13.2 and 1763 cm3. TAT and VAT were associated with multiple vascular function measures after multivariable adjustment. After BMI adjustment, TAT and VAT remained negatively associated with peripheral arterial tone and inverse carotid femoral pulse wave velocity (P < 0.02); TAT was negatively associated with hyperemic mean flow velocity (P = 0.03). Associations of TAT with vascular function were attenuated after VAT adjustment (all P > 0.06).

Conclusions

Thoracic periaortic and visceral fat are associated with microvascular function and large artery stiffness after BMI adjustment. These findings support the growing recognition of associations between ectopic fat and vascular function.
Phosphonated oligoallylamine: Synthesis, characterization in water, and development of layer by layer assembly
Authors: Negrell‐Guirao Claire , Carosio Federico , Boutevin Bernard , Cottet Hervé , Loubat Cédric
Published: June 2013

The work focuses on the synthesis and layer by layer (LbL) assembly of oligoallylamine and phosphonated oligoallylamine. To this aim, the synthesis of oligoallylamine and the phosphonated form have been done by free radical polymerization in aqueous media. First, radical polymerization of acid salt of allylamine was performed. This charged polymer could not be characterized using classical analytical techniques such as size‐exclusion chromatography and matrix‐assisted laser desorption/ionisation‐time of flight mass spectroscopy due to presence of cations. This work demonstrated the interest of capillary electrophoresis (CE) to analyze charged oligomers, using very small amounts of samples. Entangled polymer solution CE was used as a size‐based separation technique for the characterization of the molar mass distribution using indirect ultraviolet detection and calibration based on vinyl pyridine standards. Phosphorus‐containing oligoallylamines having a number‐average molar mass of 1600 g mol−1 and a 2.3 polydispersity index were obtained. When combined using the LbL approach, prepared polymers showed an exponential growth regime as demonstrated by Fourier transform infrared spectroscopy measurements. Furthermore, thermogravimetric analyses of the LbL‐assembled polymers showed an extraordinary thermal and thermo‐oxidative stability. © 2013 Wiley Periodicals, Inc. J Polym Sci Part B: Polym. Phys. 2013, 51, 1244–1251
Neisseria meningitidis expresses a single 3‐deoxy‐d‐arabino‐heptulosonate 7‐phosphate synthase that is inhibited primarily by phenylalanine
Authors: Cross Penelope J. , Pietersma Amy L. , Allison Timothy M. , Wilson‐Coutts Sarah M. , Cochrane Fiona C. , Parker Emily J.
Published: June 2013

Neisseria meningitidis is the causative agent of meningitis and meningococcal septicemia is a major cause of disease worldwide, resulting in brain damage and hearing loss, and can be fatal in a large proportion of cases. The enzyme 3‐deoxy‐d‐arabino‐heptulosonate 7‐phosphate synthase (DAH7PS) catalyzes the first reaction in the shikimate pathway leading to the biosynthesis of aromatic metabolites including the aromatic acids l‐Trp, l‐Phe, and l‐Tyr. This pathway is absent in humans, meaning that enzymes of the pathway are considered as potential candidates for therapeutic intervention. As the entry point, feedback inhibition of DAH7PS by pathway end products is a key mechanism for the control of pathway flux. The structure of the single DAH7PS expressed by N. meningitidis was determined at 2.0 Å resolution. In contrast to the other DAH7PS enzymes, which are inhibited only by a single aromatic amino acid, the N. meningitidis DAH7PS was inhibited by all three aromatic amino acids, showing greatest sensitivity to l‐Phe. An N. meningitidis enzyme variant, in which a single Ser residue at the bottom of the inhibitor‐binding cavity was substituted to Gly, altered inhibitor specificity from l‐Phe to l‐Tyr. Comparison of the crystal structures of both unbound and Tyr‐bound forms and the small angle X‐ray scattering profiles reveal that N. meningtidis DAH7PS undergoes no significant conformational change on inhibitor binding. These observations are consistent with an allosteric response arising from changes in protein motion rather than conformation, and suggest ligands that modulate protein dynamics may be effective inhibitors of this enzyme.
Conducting polymer based hybrid structure as transparent and flexible field electron emitter
Authors: Ghosh Debasish , Ghosh Pradip , Kalita Golap , Noda Takuto , Takahashi Chisato , Tanemura Masaki
Published: June 2013

An efficient cathode material with high transparency (93%) based on conducting polymer poly(3,4‐ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) and single wall carbon nanotubes (SWCNTs) has been developed for the fabrication of highly transparent and flexible field electron emitters (FEE). This kind of material showed superior field emission (FE) performance with very high current density (10–3A/cm2) at very low electric field. The FE performance of the hybrid materials was dramatically improved compared to either SWCNTs and PEDOT:PSS. Thus the hybrid structures of conducting polymer and SWCNTs might be a good choice for use as a cathode material to enhance the FE performance and for potential application in future portable displays. (© 2013 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Computational and experimental characterization of skin mechanics: identifying current challenges and future directions
Authors: Jor Jessica W.Y. , Parker Matthew D. , Taberner Andrew J. , Nash Martyn P. , Nielsen Poul M.F.
Published: June 2013

The characterization of skin mechanics has many clinical implications and has been an active area of research for the past few decades. Biomechanical models have evolved from earlier empirical models to state‐of‐the‐art structural models that provide linkage between tissue microstructure and macroscopic stress–strain response. To maximize the accuracy and predictive capabilities of such computational models, there is a need to reliably identify often a large number of unknown model parameters. This is critically dependent on the availability of experimental data that cover an extensive range of different deformation modes, and quantification of internal structural features, such as collagen orientation. To this end, future challenges should include the ongoing development of noninvasive instrumentation and imaging modalities for in vivo skin measurements. We highlight the important concept of tightly integrating computational models, instrumentation, and imaging modalities into a single platform to investigate skin biomechanics. WIREs Syst Biol Med 2013, 5:539–556. doi: 10.1002/wsbm.1228

This article is categorized under:

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models
A conceptual framework for computational models of Achilles tendon homeostasis
Authors: Smith David W. , Rubenson Jonas , Lloyd David , Zheng Minghao , Fernandez Justin , Besier Thor , Xu Jiake , Gardiner Bruce S.
Published: June 2013

Computational modeling of tendon lags the development of computational models for other tissues. A major bottleneck in the development of realistic computational models for Achilles tendon is the absence of detailed conceptual and theoretical models as to how the tissue actually functions. Without the conceptual models to provide a theoretical framework to guide the development and integration of multiscale computational models, modeling of the Achilles tendon to date has tended to be piecemeal and focused on specific mechanical or biochemical issues. In this paper, we present a new conceptual model of Achilles tendon tissue homeostasis, and discuss this model in terms of existing computational models of tendon. This approach has the benefits of structuring the research on relevant computational modeling to date, while allowing us to identify new computational models requiring development. The critically important functional issue for tendon is that it is continually damaged during use and so has to be repaired. From this follows the centrally important issue of homeostasis of the load carrying collagen fibrils within the collagen fibers of the Achilles tendon. Collagen fibrils may be damaged mechanically—by loading, or damaged biochemically—by proteases. Upon reviewing existing computational models within this conceptual framework of the Achilles tendon structure and function, we demonstrate that a great deal of theoretical and experimental research remains to be done before there are reliably predictive multiscale computational model of Achilles tendon in health and disease. WIREs Syst Biol Med 2013, 5:523–538. doi: 10.1002/wsbm.1229

This article is categorized under:

Models of Systems Properties and Processes > Organ, Tissue, and Physiological Models
Nicaraguan Surgical and Anesthesia Infrastructure: Survey of Ministry of Health Hospitals
Authors: Solis Carolina , León Pablo , Sanchez Nora , Burdic MacKenzie , Johnson Logan , Warren Hannah , Iddriss Adam , McQueen Kelly
Published: June 2013

Background

Developing countries have surgical and anesthesia needs that are unique and disparate compared to those of developed countries. However, the extent of these disparities and the specific country‐based needs are, for the most part, unknown. The goal of this study was to assess the surgical capacity of Nicaragua’s public hospitals as part of a multinational study.

Methods

A survey adapted from the World Health Organization Tool for Situational Analysis to Assess Emergency and Essential Surgical care was used to study 28 primary, departmental, regional, and national referral hospitals within the Ministry of Health system. Data were obtained at the national and hospital levels via interviews with administrators and surgical and anesthesia chiefs of services.

Results

There are 580 obstetrician/gynecologists (OB/GYN), 1,040 non‐OB/GYN surgeons, and 250 anesthesiologists in Nicaragua. Primary, departmental, regional, and national referral hospitals perform an annual average of 374, 4,610, 7,270, and 7,776 surgeries, respectively. All but six primary hospitals were able to perform surgeries. Four hospitals reported routine water shortages. Routine medication shortages were reported in 11 hospitals. Eight primary hospitals lacked blood banks on site. Of 28 hospitals, 22 reported visits from short‐term surgical brigades within the past 2 years. Measurement of surgical outcomes was inconsistent across hospitals.

Conclusions

Surgical capacity varies by hospital type, with primary hospitals having the least surgical capacity and surgical volume. Departmental, regional, and national referral hospitals have adequate surgical capacity. Surgical subspecialty care appears to be insufficient, as evidenced by the large presence of NGOs and other surgical brigade teams filling this gap.
Constant Q-curvature metrics near the hyperbolic metric
Authors: Li Gang
Published: June 2013

Let

(M,g)

be a Poincaré–Einstein manifold with a smooth defining function. In this note, we prove that there are infinitely many asymptotically hyperbolic metrics with constant
Q
-curvature in the conformal class of an asymptotically hyperbolic metric close enough to
g
. These metrics are parametrized by the elements in the kernel of the linearized operator of the prescribed constant
Q
-curvature equation. A similar analysis is applied to a class of fourth order equations arising in spectral theory.
Chronic exposure to low mercury chloride concentration induces object recognition and aversive memories deficits in rats
Authors: Mello‐Carpes Pâmela B. , Barros Wellinghton , Borges Sidnei , Alves Niége , Rizzetti Danize , Peçanha Franck M. , Vassallo Dalton V. , Wiggers Giulia A. , Izquierdo Ivan
Published: June 2013

This work examines the effects of chronic exposure to low inorganic mercury (mercury chloride, HgCl2) concentration on the recognition and aversive memories. Forty male Wistar rats were divided into 4 groups treated during 30 or 60 days with saline (control) or HgCl2 doses. After treated the animals were tested considering object recognition and inhibitory avoidance behavioral memory paradigms. Elevated plus maze, open field and tail flick tests were used to assess anxiety, locomotor and exploratory activity and pain thresholds. Only exposure for 60 days to HgCl2 induced in memory deficits quantified in the object recognition task. In the inhibitory avoidance all the animals exposed to mercury (for 30 or 60 days) presented worst performance than control animals. Our results suggest that chronic exposure to low mercury chloride concentrations impairs memory formation.
Faraday instability in floating liquid lenses: the spontaneous mutual adaptation due to radiation pressure
Authors: Pucci G. , Ben Amar M. , Couder Y.
Published: June 2013

Fluid dynamics instabilities are usually investigated in two types of situations, either confined in cells with fixed boundaries, or free to grow in open space. In this article we study the Faraday instability triggered in a floating liquid lens. This is an intermediate situation in which a hydrodynamical instability develops in a domain with flexible boundaries. The instability is observed to be initially disordered with fluctuations of both the wave field and the lens boundaries. However, a slow dynamics takes place, leading to a mutual adaptation so that a steady regime is reached with a stable wave field in a stable lens contour. The most recurrent equilibrium lens shape is elongated with the Faraday wave vector along the main axis. In this self-organized situation an equilibrium is reached between the radiation pressure exerted by Faraday waves on the borders and their capillary response. The elongated shape is obtained theoretically as the exact solution of a Riccati equation with a unique control parameter and compared with the experiment.
Spatial structure of spectral transport in two-dimensional flow
Authors: Liao Yang , Ouellette Nicholas T.
Published: June 2013

Using filter-space techniques (FSTs), we study the spatial structure of the scale-to-scale flux of energy in two-dimensional flow. Analysing data from a weakly turbulent, experimental quasi-two-dimensional flow, we find rotationally symmetric patterns consisting of lobes of spectral flux of alternating sign that are associated with vortical motion in the flow field. Such patterns also occur in a simple analytical model, even though the single-scale model flow should have no scale-to-scale energy transfer. Thus, the interpretation of these alternating patterns must be handled with care. By decomposing the spectral flux into three distinct components, we show that these lobe patterns are entirely associated with the Leonard and, to a lesser extent, cross terms. In addition, we show that the contributions from these two terms are localized around the energy injection scale, and that the bulk of the inverse energy transfer in our flow is carried by the subgrid term alone.
Inertial and barotropic instabilities of a free current in three-dimensional rotating flow
Authors: Carnevale G. F. , Kloosterziel R. C. , Orlandi P.
Published: June 2013

A current in a homogeneous rotating fluid is subject to simultaneous inertial and barotropic instabilities. Inertial instability causes rapid mixing of streamwise absolute linear momentum and alters the vertically averaged velocity profile of the current. The resulting profile can be predicted by a construction based on absolute-momentum conservation. The alteration of the mean velocity profile strongly affects how barotropic instability will subsequently change the flow. If a current with a symmetric distribution of cyclonic and anticyclonic vorticity undergoes only barotropic instability, the result will be cyclones and anticyclones of the same shape and amplitude. Inertial instability breaks this symmetry. The combined effect of inertial and barotropic instability produces anticyclones that are broader and weaker than the cyclones. A two-step scheme for predicting the result of the combined inertial and barotropic instabilities is proposed and tested. This scheme uses the construction for the redistribution of streamwise absolute linear momentum to predict the mean current that results from inertial instability and then uses this equilibrated current as the initial condition for a two-dimensional simulation that predicts the result of the subsequent barotropic instability. Predictions are made for the evolution of a Gaussian jet and are compared with three-dimensional simulations for a range of Rossby numbers. It is demonstrated that the actual redistribution of absolute momentum in the three-dimensional simulations is well predicted by the construction used here. Predictions are also made for the final number and size of vortices that result from the combined inertial and barotropic instabilities.