bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of maternal prenatal smoking on the development of childhood overweight in school‐aged children
Authors: Wang L. , Mamudu H. M. , Wu T.
Published: October 2012

What is already known about this subject

Maternal smoking during pregnancy likely increase the risk of childhood overweight.

Childhood overweight is influenced by socioeconomic characteristics of mothers.

Characteristics of child at birth determine the likelihood of overweight.

What this study adds

Children of mothers who smoked 1 year before birth (including pregnancy) were likely to be overweight during school ages than those of mothers who never smoked.

Confirmation that socioeconomic characteristics of mothers influence the likelihood of childhood overweight during school age.

Smoking cessation should be targeted at mothers 1 year before birth to improve their health status and that of offspring.

Objectives

To examine associations between maternal smoking and overweight among school‐aged children and also identify mothers and offspring characteristics that affect children's weight.

Methods

We used data from the National Institute of Child Health and Human Development (NICHD) Study of Early Child Care and Youth Development (SECCY). Childhood overweight was defined as having Body Mass Index (BMI) of 85th percentile or above. Smoking patterns among mothers were assessed by questioning smoking behaviour 1 year before birth of the target child: never or ever smoking. Standardized procedures were used to measure height and weight. Descriptive statistics and generalized estimating equations (GEE) were used for the analysis.

Results

Descriptive results showed that children of mothers who smoked anytime within 1 year before birth were more likely to be overweight and have higher BMI percentile averages. GEE results showed that children of mothers who were ever smokers 1 year before birth were more likely to be overweight (OR = 1.39, 95% CI: 1.01, 1.94) and have higher BMI percentile averages (β = 4.46, P = 0.036) from grades 1 through 6 than those of mothers who were never smokers. Additionally, the level of mother's education and birth weight were significantly associated with childhood overweight.

Conclusions

Confirmed relationships between maternal smoking and overweight among school‐aged children have important implications for public health policy because this evidence can be used to enhance smoking cessation 1 year before birth to improve the health status of mothers and offspring.
Analysis of genetic diversity in Bolivian llama populations using microsatellites
Authors: Barreta J. , Gutiérrez‐Gil B. , Iñiguez V. , Romero F. , Saavedra V. , Chiri R. , Rodríguez T. , Arranz J.J.
Published: October 2012

South American camelids (SACs) have a major role in the maintenance and potential future of rural Andean human populations. More than 60% of the 3.7 million llamas living worldwide are found in Bolivia. Due to the lack of studies focusing on genetic diversity in Bolivian llamas, this analysis investigates both the genetic diversity and structure of 12 regional groups of llamas that span the greater part of the range of distribution for this species in Bolivia. The analysis of 42 microsatellite markers in the considered regional groups showed that, in general, there were high levels of polymorphism (a total of 506 detected alleles; average PIC across per marker: 0.66), which are comparable with those reported for other populations of domestic SACs. The estimated diversity parameters indicated that there was high intrapopulational genetic variation (average number of alleles and average expected heterozygosity per marker: 12.04 and 0.68, respectively) and weak genetic differentiation among populations (FST range: 0.003–0.052). In agreement with these estimates, Bolivian llamas showed a weak genetic structure and an intense gene flow between all the studied regional groups, which is due to the exchange of reproductive males between the different flocks. Interestingly, the groups for which the largest pairwise FST estimates were observed, Sud Lípez and Nor Lípez, showed a certain level of genetic differentiation that is probably due to the pattern of geographic isolation and limited communication infrastructures of these southern localities. Overall, the population parameters reported here may serve as a reference when establishing conservation policies that address Bolivian llama populations.
Radiographic evaluation of different techniques for ridge preservation after tooth extraction: a randomized controlled clinical trial
Authors: Jung Ronald E. , Philipp Alexander , Annen Beat M. , Signorelli Luca , Thoma Daniel S. , Hämmerle Christoph H.F. , Attin Thomas , Schmidlin Patrick
Published: October 2012

Objective

To evaluate the radiographic changes of the alveolar ridge following application of different ridge preservation techniques 6 months after tooth extraction.

Materials and Methods

Four treatment modalities were randomly assigned in 40 patients: β‐tricalcium‐phosphate‐particles with polylactid coating (β‐TCP), demineralized bovine bone mineral with 10% collagen covered with a collagen matrix (DBBM‐C/CM), DBBM‐C covered with an autogenous soft‐tissue graft (DBBM‐C/PG) and spontaneous healing (control). Cone‐beam computed tomography scans were performed after treatment and 6 months later.

Results

After 6 months, the vertical changes ranged between −0.6 mm (−10.2%) for control and a gain of 0.3 mm (5.6%) for DBBM‐C/PG on the lingual side, and between −2.0 mm (−20.9%) for β‐TCP and a gain of 1.2 mm (8.1%) for DBBM‐C/PG on the buccal side. The most accentuated ridge width changes were recorded 1 mm below the crest: −3.3 mm (−43.3%, C), −6.1 mm (−77.5%, β‐TCP), −1.2 mm (−17.4%, DBBM‐C/CM) and −1.4 mm (−18.1%, DBBM‐C/PG). At all three levels, DBBM‐C with either CM or PG was not significantly differing (p > 0.05), while most other differences between the groups reached statistical significance (p < 0.05).

Conclusions

Application of DBBM‐C, covered with CM or PG, resulted in less vertical and horizontal changes of the alveolar ridge as compared with controls 6 months after extraction.
Bayesian network meta‐analysis of root coverage procedures: ranking efficacy and identification of best treatment
Authors: Buti Jacopo , Baccini Michela , Nieri Michele , La Marca Michele , Pini‐Prato Giovan P.
Published: October 2012

Aims

The aim of this work was to conduct a Bayesian network meta‐analysis (NM) of randomized controlled trials (RCTs) to establish a ranking in efficacy and the best technique for coronally advanced flap (CAF)‐based root coverage procedures.

Material and Methods

A literature search on PubMed, Cochrane libraries, EMBASE, and hand‐searched journals until June 2012 was conducted to identify RCTs on treatments of Miller Class I and II gingival recessions with at least 6 months of follow‐up. The treatment outcomes were recession reduction (RecRed), clinical attachment gain (CALgain), keratinized tissue gain (KTgain), and complete root coverage (CRC).

Results

Twenty‐nine studies met the inclusion criteria, 20 of which were classified as at high risk of bias. The CAF+connective tissue graft (CTG) combination ranked highest in effectiveness for RecRed (Probability of being the best = 40%) and CALgain (Pr = 33%); CAF+enamel matrix derivative (EMD) was slightly better for CRC; CAF+Collagen Matrix (CM) appeared effective for KTgain (Pr = 69%). Network inconsistency was low for all outcomes excluding CALgain.

Conclusion

CAF+CTG might be considered the gold standard in root coverage procedures. The low amount of inconsistency gives support to the reliability of the present findings.
Ultrahigh‐pressure metamorphism in the magnesite + aragonite stability field: evidence from two impure marbles from the Dabie–Sulu UHPM belt
Authors: PROYER A. , ROLFO F. , ZHU Y.‐F. , CASTELLI D. , COMPAGNONI R.
Published: October 2012

Two magnesite‐bearing impure dolomitic marbles from the Dabie–Sulu ultrahigh‐pressure (UHP) region have been investigated to clarify if they had actually attained P–T conditions outside the dolomite stability field, limited by the reaction dolomite = aragonite + magnesite, and to test their potential for recording (U)HP conditions. In both cases, the silicate mineral assemblage records conditions around the terminal amphibole breakdown reaction: amphibole + aragonite ± quartz = clinopyroxene + talc, which is a good geobarometer between at least 2.0 and 2.6 GPa. At higher pressures, the terminal breakdown of talc to clinopyroxene + coesite is the last P–T milestone below 4 GPa recordable by the silicate assemblage, but evidence of former coesite is ambiguous. The dolomite dissociation curve becomes strongly divariant in Fe‐bearing marbles and may thus be attainable during cold subduction near the 5 °C km−1‘geotherm’. At least one of the samples (from Xinyan village, near Taihu, Dabie Shan) preserved relicts of both magnesite and aragonite and most likely attained conditions within the aragonite + magnesite stability field. For the second sample from Sanqingge village in the Sulu terrane, no certain evidence has been found in this study. Impure dolomitic marbles have considerable potential to preserve (ultra)high‐pressure relicts. Particularly, massive impure marbles that have not been pervasively infiltrated by fluids during exhumation are considered to preserve high‐pressure relicts better than metapelites, paragneisses and orthogneisses, and perhaps almost as well as eclogites or metaperidotites. The inconspicuous mineral assemblage clinopyroxene + talc or quartz (after former coesite) may in fact record UHP conditions.
New evidence of blueschist facies rocks and their geotectonic implication for Variscan suture(s) in the Bohemian Massif
Authors: FARYAD S. W. , KACHLÍK V.
Published: October 2012

Blueschist facies rocks, exposed within consolidated continental blocks, provide some of the best evidence for the existence of previous suture(s). They usually occur as lenses or layers embedded within greenschist or amphibolite facies rocks and indicate reequilibration at medium‐ to low‐pressure conditions. In the Bohemian Massif, a few occurrences of blueschists have been reported, and here, new evidence of high‐pressure (HP) metamorphism in various lithologies is presented that suggests a larger extent of blueschist facies rocks along the northern border of this Massif. An earlier blueschist facies metamorphism is documented by inclusions of glaucophane in garnet, epidote and titanite from metabasites along with zoned white mica having a phengitic core and a muscovite rim in metapelites and orthogneisses. The estimated P–T conditions, obtained using pseudosections and mineral isopleths, correspond to blueschist and low‐temperature eclogite facies conditions (1.1–2.0 GPa at 350–550 °C). Together with medium‐temperature eclogites from different units in the Bohemian Massif they indicate a geothermal gradient of 8–10 °C km−1, which is typical for cool subduction. Radiometric dating on phengite from metapelites confirms an early Palaeozoic cooling age of c. 360 Ma for this HP metamorphic event. The presence of blueschist facies rocks, their P–T relations and age constraint together with those from eclogite facies rocks allows us to locate the Variscan suture, which straddles the SE margin of Saxothuringian Zone from Erzgebirge to Sudetes, and its possible continuation to the Moldanubian Zone, where eclogite facies and UHPM rocks are abundant.
First find of polycrystalline diamond in ultrahigh‐pressure metamorphic terrane of Erzgebirge, Germany
Authors: DOBRZHINETSKAYA L. F. , WIRTH R. , GREEN H.W. , SCHREIBER A. , O’BANNON E.
Published: October 2012

This article describes polycrystalline diamond from the Erzgebirge ultrahigh‐pressure metamorphic (UHPM) terrane of the Bohemian massif related to the Variscan (340 Ma) continent–continent collision. The foils polycrystalline diamond included in zircon were prepared with focused ion beam (FIB) and studied with transmission electron microscopy (TEM). Each domain of the polycrystalline diamond consisted of a series of diamond monocrystals (from 1 to 4 up to 15) containing numerous nanometric fluid and crystalline inclusions of SiO2, CaCO3, KCl and KAlSi3O8. The integrated chemistry of the nanoinclusions suggests that the polycrystalline diamond was crystallized from a mixture of two end‐members, which includes a carbon‐rich hydrous‐silicic fluid containing Si, Al, K and a hydrous‐saline fluid rich in Cl, K, Na. Traces of carbonate, sulphate and phosphate coupled with the presence of metallic cations such as Fe, Mg, Ti, Cr, Co, Zn, Zr, Pb, As and Hg found in the diamond are coherent with the local geochemical diversity of the host metasedimentary rocks. The oxidation state of the diamond‐forming fluid was close to C–CO buffer, for example, fO2 = −6 log units, which is at the upper limit of the diamond stability region. The presence of dislocation arrays indicating low‐angle grain boundaries together with ‘zig‐zag’ features or kinks at diamond grain boundaries reflects rapid crystallization of the polycrystalline diamond. Triangular fluid pockets with steps at the surface related to {110} and {111} planes of diamond could promote the formation of C–H and C–OH bonds that probably could facilitate the process of diamond graphitization. The microstructural features of polycrystalline diamond from the Erzgebirge UHPM terrane as well as their undisputed formation from crustal/organic carbon can be used for better understanding of the origin of any polycrystalline diamond formation from both kimberlitic and alluvial sources, including enigmatic polycrystalline black diamond – commonly called carbonado.
Origin and Tectonic Implication of Ophiolite and Eclogite in the Song Ma Suture Zone between the South China and Indochina Blocks
Authors: ZHANG R. Y. , LO C.‐H. , CHUNG S.‐L. , GROVE M. , OMORI S. , IIZUKA Y. , LIOU J. G. , TRI T. V.
Published: October 2012

Southeast Asia consists of several microcontinents that detached from the northeastern margin of Gondwanaland. The Song Ma belt in northern Vietnam consists of ophiolite, metabasite, metasedimentary rocks and eclogite, and it is thought to be a suture zone between the Indochina and South China blocks. However, the nature and boundaries of the Song Ma belt and the collision age of the two blocks have long been debated. In this article, petrological and geochemical studies on the Song Ma ophiolite and eclogite and first sensitive high‐resolution ion microprobe (SHRIMP) age dating of eclogite provide new light to resolve such debate. Eclogite consisting of garnet, omphacite, phengite, quartz, barroisite and rutile is closely associated with garnet–phengite–quartz schist in the ‘Nam Co antiform’, a northern subunit of the Song Ma belt. The eclogite experienced a three‐stage metamorphic evolution: (I) pre‐eclogite stage (amphibolite facies) defined by inclusions of taramite, barroisite, quartz, zoisite/epidote, mica, rutile & rare chlorite in garnet, (II) eclogite stage and (III) retrograde stage of amphibolite to greenschist facies. The P–T conditions of the three stages are of 14–16 kbar and 520–550 °C (I), 24–27 kbar and 650–750 °C (II), and 3–7 kbar and 430–510 °C (III), and show a clockwise P–T path based on their mineral assemblages and stability fields in the P–T pseudosection. Thermobarometric results yield similar peak pressure and temperature (26–28 kbar and 650–710 °C). These data suggest that the Song Ma eclogite underwent high‐pressure metamorphism in subduction zone with a low thermal gradient ∼8 °C km−1. The Song Ma ophiolite is composed of serpentinized peridotite, gabbro, basalt, mafic dyke and chert, and experienced ocean‐floor metamorphism. Metabasalt and gabbro of ophiolite suite and eclogite all have MORB‐type geochemical affinities. Zircon separates from eclogite have very low Th/U ratios of 0.01–0.05, indicating a metamorphic origin. SHRIMP U–Pb isotopic analyses of this zircon yield a 206Pb/238U weighted mean age of 230.5 ± 8.2 Ma. This age is interpreted as the closure age of the Paleotethys Ocean that separated the South China and Indochina blocks, and the subsequent collision of the two blocks that took place at the Middle Triassic corresponding to the major episode of the Indosinian Orogeny.
Distribution of the branched chain aminotransferase proteins in the human brain and their role in glutamate regulation
Authors: Hull Jonathon , Hindy Maya El , Kehoe Patrick G. , Chalmers Katy , Love Seth , Conway Myra E.
Published: October 2012

The branched chain aminotransferase enzymes (BCAT) serve as nitrogen donors for the production of 30% of de novo glutamate synthesis in rat brain. Despite the importance of this major metabolite and excitatory neurotransmitter, the distribution of BCAT proteins in the human brain (hBCAT) remains unreported. We have studied this and report, for the first time, that the mitochondrial isoform, hBCATm is largely confined to vascular endothelial cells, whereas the cytosolic hBCATc is restricted to neurons. The majority of hBCATc‐labelled neurons were either GABA‐ergic or glutamatergic showing both cell body and axonal staining indicating a role for hBCATc in both glutamate production and glutamate release during excitation. Strong staining in hormone secreting cells suggests a further role for the transaminases in hormone regulation potentially similar to that proposed for insulin secretion. Expression of hBCATm in the endothelial cells of the vasculature demonstrates for the first time that glutamate could be metabolized by aminotranferases in these cells. This has important implications given that the dysregulation of glutamate metabolism, leading to glutamate excitotoxicity, is an important contributor to the pathogenesis of several neurodegenerative conditions, where the role of hBCATm in metabolizing excess glutamate may factor more prominently.
S‐nitrosylated protein disulfide isomerase contributes to mutant SOD1 aggregates in amyotrophic lateral sclerosis
Authors: Chen Xueping , Zhang Xiaosha , Li Chen , Guan Teng , Shang Huifang , Cui Liying , Li Xin‐Min , Kong Jiming
Published: October 2012

A major hallmark of mutant superoxide dismutase (SOD1)‐linked familial amyotrophic lateral sclerosis is SOD1‐immunopositive inclusions found within motor neurons. The mechanism by which SOD1 becomes aggregated, however, remains unclear. In this study, we aimed to investigate the role of nitrosative stress and S‐nitrosylation of protein disulfide isomerase (PDI) in the formation of SOD1 aggregates. Our data show that with disease progression inducible nitric oxide synthase (iNOS) was up‐regulated, which generated high levels of nitric oxide (NO) and subsequently induced S‐nitrosylation of PDI in the spinal cord of mutant SOD1 transgenic mice. This was further confirmed by in vitro observation that treating SH‐SY5Y cells with NO donor S‐nitrosocysteine triggered a dose‐dependent formation of S‐nitrosylated PDI. When mutant SOD1 was over‐expressed in SH‐SY5Y cells, the iNOS expression was up‐regulated, and NO generation was consequently increased. Furthermore, both S‐nitrosylation of PDI and the formation of mutant SOD1 aggregates were detected in the cells expressing mutant SOD1G93A. Blocking NO generation with the NOS inhibitor N‐nitro‐l‐arginine attenuated the S‐nitrosylation of PDI and inhibited the formation of mutant SOD1 aggregates. We conclude that NO‐mediated S‐nitrosylation of PDI is a contributing factor to the accumulation of mutant SOD1 aggregates in amyotrophic lateral sclerosis.
Hypoxic preconditioning induces stroke tolerance in mice via a cascading HIF, sphingosine kinase, and CCL2 signaling pathway
Authors: Wacker Bradley K. , Perfater Jennifer L. , Gidday Jeffrey M.
Published: October 2012

The induction of ischemic tolerance by preconditioning provides a platform to elucidate endogenous mechanisms of stroke protection. In these studies, we characterize the relationship between hypoxia‐inducible factor (HIF), sphingosine kinase 2 (SphK2), and chemokine (C–C motif) ligand 2 (CCL2) in models of hypoxic or pharmacological preconditioning‐induced ischemic tolerance. A genetics‐based approach using SphK2‐ and CCL2‐null mice showed both SphK2 and CCL2 to be necessary for the induction of ischemic tolerance following preconditioning with hypoxia, the hypoxia‐mimetic cobalt chloride, or the sphingosine‐1‐phosphate (S1P) agonist FTY720. A pharmacological approach confirmed the necessity of HIF signaling for all three preconditioning stimuli, and showed that the SphK/S1P pathway transduces tolerance via the S1P1 receptor. In addition, our data suggest significant cross‐talk between HIF and SphK2‐produced S1P signaling, which together act to up‐regulate CCL2 expression. Overall, HIF, SphK, S1P, and CCL2 participate in a signaling cascade to induce the gene expression responsible for the stroke‐tolerant phenotype established by hypoxic and FTY720 preconditioning. The identification of these common molecular mediators involved in signaling the genomic response to multiple preconditioning stimuli provides several targets for therapeutic manipulation.
Occlusal‐supporting ability of individual maxillary and mandibular teeth
Authors: Abe Y. , Nogami K. , Mizumachi W. , Tsuka H. , Hiasa K.
Published: October 2012

This study aimed to analyse occlusal force, area and pressure for individual maxillary and mandibular teeth by assessing their occlusal‐supporting abilities. Ninety‐nine subjects (49 men and 50 women; average age, 24·7 ± 3·4 years; range, 20–37 years) performed maximal voluntary clenching twice for 3 s in both the intercuspal position and the intercuspal position with sliding movement from edge‐to‐edge occlusion, with a pressure‐sensitive sheet placed between the maxillary and mandibular dental arch. Occlusal force, area and pressure of individual teeth were calculated by colour development in the pressure‐sensitive sheet with special analytical equipment and software. Occlusal contact condition of individual teeth was confirmed using the intra‐occlusal record. All data were analysed using unpaired Student's t‐test, Kruskal–Wallis test and Scheffe's test for multiple comparisons with a significance level of P < 0·05. The occlusal pressure in the intercuspal position with sliding movement from edge‐to‐edge occlusion was adopted as the representative occlusal‐supporting ability for each individual tooth, although there were, in part, statistically significant differences in the effects of laterality, performance and gender. Overall, the occlusal pressure increased gradually from the central incisor, peaked at the canine or first premolar and decreased sharply–and significantly (P < 0·01)–towards the second molar. We conclude that the occlusal pressure of individual teeth can be used as an indicator of occlusal‐supporting ability. This is therefore proposed as a possible suitable parameter for epidemiologic research, specifically for verifying the relationship between occlusal‐supporting ability and status of residual periodontal ligament support.
Melatonin treatment improves adipose‐derived mesenchymal stem cell therapy for acute lung ischemia–reperfusion injury
Authors: Yip Hon‐Kan , Chang Yi‐Chih , Wallace Christopher Glenn , Chang Li‐Teh , Tsai Tzu‐Hsien , Chen Yung‐Lung , Chang Hsueh‐Wen , Leu Steve , Zhen Yen‐Yi , Tsai Ching‐Yen , Yeh Kuo‐Ho , Sun Cheuk‐Kwan , Yen Chia‐Hung
Published: October 2012

This study investigated whether melatonin‐treated adipose‐derived mesenchymal stem cells (ADMSC) offered superior protection against acute lung ischemia–reperfusion (IR) injury. Adult male Sprague‐Dawley rats (n = 30) were randomized equally into five groups: sham controls, lung IR–saline, lung IR–melatonin, lung IR–melatonin–normal ADMSC, and lung IR–melatonin–apoptotic ADMSC. Arterial oxygen saturation was lowest in lung IR–saline; lower in lung IR–melatonin than sham controls, lung IR–melatonin–normal ADMSC, and lung IR–melatonin–apoptotic ADMSC; lower in lung IR–melatonin–normal ADMSC than sham controls and lung IR–melatonin–apoptotic ADMSC; lower in lung IR–melatonin–apoptotic ADMSC than sham controls (P < 0.0001 in each case). Right ventricular systolic blood pressure (RVSBP) showed a reversed pattern among all groups (all P < 0.0001). Changes in histological scoring of lung parenchymal damage and CD68+ cells showed a similar pattern compared with RVSBP in all groups (all P < 0.001). Changes in inflammatory protein expressions such as VCAM‐1, ICAM‐1, oxidative stress, TNF‐α, NF‐κB, PDGF, and angiotensin II receptor, and changes in apoptotic protein expressions of cleaved caspase 3 and PARP, and mitochondrial Bax, displayed identical patterns compared with RVSBP in all groups (all P < 0.001). Numbers of antioxidant (GR+, GPx+, NQO‐1+) and endothelial cell biomarkers (CD31+ and vWF+) were lower in sham controls, lung IR–saline, and lung IR–melatonin than lung IR–melatonin–normal ADMSC and lung IR–melatonin–apoptotic ADMSC, and lower in lung IR–melatonin–normal ADMSC than lung IR–melatonin–apoptotic ADMSC (P < 0.001 in each case). In conclusion, when the animals were treated with melatonin, the apoptotic ADMSC were superior to normal ADMSC for protection of lung from acute IR injury.
Temperature‐dependent, behavioural, and transcriptional variability of a tritrophic interaction consisting of bean, herbivorous mite, and predator
Authors: Ozawa Rika , Nishimura Osamu , Yazawa Shigenobu , Muroi Atsushi , Takabayashi Junji , Arimura Gen‐ichiro
Published: October 2012

Different organisms compensate for, and adapt to, environmental changes in different ways. In this way, environmental changes affect animal–plant interactions. In this study, we assessed the effect of temperature on a tritrophic system of the lima bean, the herbivorous spider mite Tetranychus urticae and the predatory mite Phytoseiulus persimilis. In this system, the plant defends itself against T. urticae by emitting volatiles that attract P. persimilis. Over 20–40 °C, the emission of volatiles by infested plants and the subsequent attraction of P. persimilis peaked at 30 °C, but the number of eggs laid by T. urticae adults and the number of eggs consumed by P. persimilis peaked at 35 °C. This indicates that the spider mites and predatory mites performed best at a higher temperature than that at which most volatile attractants were produced. Our data from transcriptome pyrosequencing of the mites found that P. persimilis up‐regulated gene families for heat shock proteins (HSPs) and ubiquitin‐associated proteins, whereas T. urticae did not. RNA interference‐mediated gene suppression in P. persimilis revealed differences in temperature responses. Predation on T. urticae eggs by P. persimilis that had been fed PpHsp70‐1 dsRNA was low at 35 °C but not at 25 °C when PpHsp70‐1 expression was very high. Overall, our molecular and behavioural approaches revealed that the mode and tolerance of lima bean, T. urticae and P. persimilis are distinctly affected by temperature variability, thereby making their tritrophic interactions temperature dependent.
A population genetic signature of human releases in an invasive ladybeetle
Authors: Kajita Yukie , O'Neill Eric M. , Zheng Yanbing , Obrycki John J. , Weisrock David W.
Published: October 2012

Biological invasions have been accelerated by a variety of human activities. Propagule pressure, the number of introduced individuals and independent introductions, is probably to be influenced by these human activities and may be an important factor for successful range expansion in new environments. We tested whether the current distribution of the predatory ladybeetle Coccinella septempunctata in the introduced range (USA) is the result of multiple historical human introductions or natural range expansion from the first established populations in the USA. To test this hypothesis, we compared historical records of propagule size, propagule number, specific introduction locations and the date of each introduction, with estimates of genetic variation in mitochondrial DNA (cytochrome oxidase I). Our results indicated that genetic diversity in the introduced range was positively correlated with historical records of propagule size and number and negatively correlated with distance to nearest introduction point, suggesting that multiple human releases were successful. Higher genetic diversity in populations found near introduction points suggest that initial founder effects were limited, but lower genetic diversity found farther from introduction points is probably the result of serial founder effects during secondary range expansion. These results suggest that the current distribution of C. septempunctata in the introduced range is the result of a combination of human releases and short‐range expansion from multiple established populations in the introduced range.
The ribosome binding site of a mini‐ORF protects a T3SS mRNA from degradation by RNase E
Authors: Lodato Patricia B. , Hsieh Ping‐Kun , Belasco Joel G. , Kaper James B.
Published: October 2012

Enterohaemorrhagic Escherichia coli harbours a pathogenicity island encoding a type 3 secretion system used to translocate effector proteins into the cytosol of intestinal epithelial cells and subvert their function. The structural proteins of the translocon are encoded in a major espADB mRNA processed from a precursor. The translocon mRNA should be highly susceptible to RNase E cleavage because of its AU‐rich leader region and monophosphorylated 5′‐terminus, yet it manages to avoid rapid degradation. Here, we report that the espADB leader region contains a strong Shine–Dalgarno element (SD2) and a translatable mini‐ORF of six codons. Disruption of SD2 so as to weaken ribosome binding significantly reduces the concentration and stability of esp mRNA, whereas codon substitutions that impair translation of the mini‐ORF have no such effect. These findings suggest that occupancy of SD2 by ribosomes, but not mini‐ORF translation, helps to protect espADB mRNA from degradation, likely by hindering RNase E access to the AU‐rich leader region.
Escherichia coliDNA polymerase III is responsible for the high level of spontaneous mutations in mutT strains
Authors: Yamada Masami , Shimizu Masatomi , Katafuchi Atsushi , Grúz Petr , Fujii Shingo , Usui Yukio , Fuchs Robert P. , Nohmi Takehiko
Published: October 2012

Reactive oxygen species induce oxidative damage in DNA precursors, i.e. dNTPs, leading to point mutations upon incorporation. Escherichia coli mutT strains, deficient in the activity hydrolysing 8‐oxo‐7,8‐dihydro‐2′‐deoxyguanosine 5′‐triphosphate (8‐oxo‐dGTP), display more than a 100‐fold higher spontaneous mutation frequency over the wild‐type strain. 8‐oxo‐dGTP induces A to C transversions when misincorporated opposite template A. Here, we report that DNA pol III incorporates 8‐oxo‐dGTP ≈ 20 times more efficiently opposite template A compared with template C. Single, double or triple deletions of pol I, pol II, pol IV or pol V had modest effects on the mutT mutator phenotype. Only the deletion of all four polymerases led to a 70% reduction of the mutator phenotype. While pol III may account for nearly all 8‐oxo‐dGTP incorporation opposite template A, it only extends ≈ 30% of them, the remaining 70% being extended by the combined action of pol I, pol II, pol IV or pol V. The unique property of pol III, a C‐family DNA polymerase present only in eubacteria, to preferentially incorporate 8‐oxo‐dGTP opposite template A during replication might explain the high spontaneous mutation frequency in E. coli mutT compared with the mammalian counterparts lacking the 8‐oxo‐dGTP hydrolysing activities.
Estimating the Angular Velocity From Body-Fixed Accelerometers
Authors: He Peng , Cardou Philippe
Published: October 2012

This paper presents a novel way of determining the angular velocity of a rigid body from accelerometer measurements. This method finds application in crashworthiness and motion analysis in sports, for example, where impacts forbid the use of mechanical gyroscopes. Based on previous work, the time-integration (TI) and polynomial-roots (PR) estimates of the angular velocity are first computed. The TI and PR estimates are then linearly combined through a weighted sum whose weighting factor is chosen so as to minimize the `variance of the resulting estimate. The proposed method is illustrated in an experiment, where the twelve accelerometer array (OCTA) is moved manually. A comparison of the angular-velocity estimates obtained from the proposed method and those obtained from a magnetic displacement sensor shows that the resulting estimates are robust and do not suffer from the drift problems that hinder the TI method. Moreover, comparison with a previously reported method indicates that the method proposed here is less sensitive to measurement errors, especially at low angular velocities.
New Finite Element Modeling Approach of a Propagating Shaft Crack
Authors: Kulesza Zbigniew , Sawicki Jerzy T.
Published: October 2012

Transverse shaft cracks are one of the most dangerous malfunctions of the rotating machines, including turbo- and hydrogenerators, high-speed machine tool spindles, etc. The undetected crack may grow slowly and not disturb normal machine operation. However, if it extends to a critical depth, the immediate shaft fracture may completely damage the machine, resulting in a catastrophic accident. Therefore, in-depth knowledge of the crack propagation process is essential to ensure reliable and safe operation of rotating machinery. The article introduces a new model of the propagating shaft crack. The approach is based on the rigid finite element (RFE) method, which has previously proven its effectiveness in the dynamical analysis of numerous complicated machines and structures. The crack is modeled using several dozen spring-damping elements (SDEs), connecting the faces of the cracked section of the shaft. By controlling the exact behavior of individual SDEs, not only the breathing mechanism, but also the crack propagation process can be simply introduced. In order to accomplish this, the stress intensity factors (SIFs) along the crack edge are calculated using the novel approach based on the modified virtual crack closure technique (VCCT). Based on the SIF values, the crack propagation rate is calculated from the Paris law. If the number of load cycles is greater than the constantly updated threshold number, then the crack edge is shifted by a small increment. This way, starting from the first initially cracked SDE, the crack is extended little by little, continuously changing its shape. The approach is illustrated with numerical results, demonstrating the changes in the rotor vibration response and in the crack shape and also explaining some issues about the breathing mechanism due to the propagating shaft crack. The increasing amplitude of the 2X harmonic component is recognized as an evident propagating crack signature. The numerical results correspond well with the data reported in the literature. The RFE model of the rotor is validated by comparing the vibration responses obtained experimentally and numerically. A good agreement between these data confirms the correctness and accuracy of the proposed model. The suggested approach may be utilized for a more reliable dynamic analysis of the rotating shafts, having the potential to experience propagating transverse cracks.
Elastic-Plastic Analysis of Adhesive Sliding Contacts
Authors: Xu H. , Komvopoulos K.
Published: October 2012

The effect of adhesion on the elastic-plastic deformation of sliding contacts was examined with the finite element method. The adhesive interaction of a rigid asperity moving over a homogeneous elastic-plastic half-space was modeled by nonlinear springs obeying a constitutive law derived from the Lennard–Jones potential. The effects of the work of adhesion, interaction distance (interfacial gap), Maugis parameter, and plasticity parameter (defined as the work of adhesion divided by the half-space yield strength and the intermolecular equilibrium distance) on the evolution of the normal and friction forces, subsurface stresses, and plastic deformation at steady-state sliding are interpreted in light of finite element results of displacement-control simulations of sliding contact. The normal and friction forces and the rate of energy dissipation due to plastic deformation at steady-state sliding sharply increase with the interaction distance. Although a higher work of adhesion produces a lower normal force, it also intensifies the friction force, enhances material pile-up ahead of the sliding asperity, and exacerbates the asymmetry of both the deformed surface profile and the normal stress field. The variation of the normal force with the plasticity parameter is explained by the dominant effect of subsurface plastic deformation above a critical plasticity parameter. Simulation results are shown to be in good agreement with those of previous experimental and numerical studies.
Simulation of the Transient Behavior of Gels Based on an Analogy Between Diffusion and Heat Transfer
Authors: Duan Zheng , Zhang Jiaping , An Yonghao , Jiang Hanqing
Published: October 2012

The transient behaviors of the swelling and deswelling of gels involve concurrent mechanical deformation and solvent diffusion and exhibit a fascinating phenomenon. In this paper, a simple numerical tool is developed by using an analogy between diffusion and heat transfer when large deformation presents for gels. Using this analogy, a finite element method is developed in the framework of a commercial finite element package ABAQUS via two material-specific user subroutines to describe the mechanical and mass diffusion behaviors of gels. The present method is not limited to any specific materials; therefore, this method can be extended to other materials that featured with coupled deformation and diffusion. This method is expected to be able to serve as a useful numerical tool to study related materials and problems due to its simplicity.
Ion conduction in nanoscale yttria-stabilized zirconia fabricated by atomic layer deposition with various doping rates
Authors: Sik Son Kyung , Bae Kiho , Woo Kim Jun , Suk Ha Jeong , Hyung Shim Joon
Published: October 2012

The ion conduction of yttria-stabilized zirconia (YSZ) was studied by varying the doping ratios during atomic layer deposition (ALD). The ALD cycle ratio for the yttria and zirconia depositions was varied from 1:1 to 1:6, which corresponded to the doping ratios from 28.8% to 4.3%. The in-plane conductivity of ALD YSZ was enhanced by up to 2 orders of magnitude; the optimal ALD doping ratio (10.4%) was found to differ from that of bulk YSZ (8%). This different relationship between the doping ratio and the ion conduction for ALD YSZ versus bulk YSZ is due to the inhomogeneous doping in the vertical direction of the ALD YSZ films, as opposed to the homogenous doping of bulk YSZ.
Effect of bilayer geometry on the diffusion of Ni in amorphous Si and the consequent growth of silicides
Authors: Ahamad Mohiddon Mahamad , Ghanashyam Krishna Mamidipudi
Published: October 2012

The deposition and annealing of nickel-amorphous silicon (a-Si) bilayer thin films on fused silica substrates is reported. Two bilayer geometries that consisted of an a-Si layer and the Ni layer over and below it, respectively, are investigated. The bilayers were deposited at temperatures between 200 and 550 °C, and in each case, postdeposition annealed in vacuum at the temperature of deposition to study the effect of geometry on the diffusion process. The diffusion process is illustrated using cross-sectional scanning electron microscopy in conjunction with energy dispersive spectrometry. The study reveals that, independent of geometry, the top surface of Ni/Si bilayers is abundant in Ni after annealing. In the geometry when Ni is at the top, x-ray diffraction and Raman spectroscopy studies reveal that, at temperatures <400 °C, there is no reaction between the Ni and the Si. The Ni-Si reaction occurs at temperatures >400 °C to form NiSi2. However, when Ni is at the bottom of the Si layer at a temperature of 200 °C itself, a nickel rich silicide Ni31Si12 forms. This is in addition to nanocrystallization of Ni. In the case when Nickel is at the bottom, most of the energy is taken up in diffusion and crystallization of Ni. The remaining energy is then used to react with the Si, leading to the formation of Ni31Si12 and its crystallization. At temperatures >500 °C, Ni reacts with Si to form NiSi2. When Ni is at the top, since it is already at its preferred location most of the energy is used up in crystallization of Ni and reaction of Ni with Si and crystallization of NiSi2. Importantly, in both cases, the energy is insufficient to cause crystallization of Si.
Hot embossing of thick amorphous fluoropolymer for back end processing of infrared arrays
Authors: Markunas Justin K. , Smith Peter J. , Melngailis John
Published: October 2012

A process is presented for patterning vias into thick amorphous fluoropolymer layers for a novel In bump fabrication process, achieved using a hot embossing technique. The technique uses a patterned Si stamp that employs a two-step etching process to obtain pillars with a controlled positive sidewall angle. After embossing with the Si stamp, vias are formed in amorphous fluoropolymer layers. A postembossing blanket reactive ion etch step is then used to remove excess fluoropolymer from the bottoms of the vias, exposing a Ni film. Successful electroplating of In bumps into vias initiated at the Ni layer is demonstrated, confirming complete removal of excess fluoropolymer.
Reflection high-energy electron diffraction evaluation of thermal deoxidation of chemically cleaned Si, SiGe, and Ge layers for solid-source molecular beam epitaxy
Authors: Ali Dyan , Richardson Christopher J. K.
Published: October 2012

The authors present a study on the thermal evolution of the reflection high-energy electron diffraction pattern of chemically cleaned (001)-oriented Si, Ge, and SiGe surfaces, associating observed changes in the reconstructions with the desorption of known residual contaminants for Si and Ge surfaces. The implications of residual oxides prior to epitaxy on stacking fault densities in the grown films are presented. Further evidence for the two-phase nature of oxides on SiGe surfaces is provided, demonstrating that it is necessary to heat a SiGe surface up to the thermal deoxidation temperature of a Si surface to obtain stacking fault-free growth.
Optimization of K‐edge imaging with spectral CT
Authors: He Peng , Wei Biao , Cong Wenxiang , Wang Ge
Published: October 2012

Purpose:

Spectral/multienergy CT has the potential to distinguish different materials by K‐edge characteristics. K‐edge imaging involves the two energy bins on both sides of a K‐edge. The authors propose a K‐edge imaging optimization model to determine these two energy bins.

Methods:

K‐edge image contrast with spectral CT depends on the specifications of the two energy bins on both sides of a K‐edge in the attenuation profile of a relatively high atomic number material. The wider the energy bin width is, the lower the noise level is, and the poorer the reconstructed image contrast is. Here the authors introduce the signal difference to noise ratio (SDNR) criterion to optimize the energy bin widths on both sides of the K‐edge for the maximum SDNR.

Results:

The authors study K‐edge imaging with spectral CT, analyze the effect of K‐edge energy bins on the resultant image quality, and establish guidelines for the optimization of energy thresholds. In simulation, the authors demonstrate that our K‐edge imaging optimization approach maximizes SDNR in reconstructed images.

Conclusions:

This proposed approach can be readily generalized to deal with more general settings and determine the best energy bins for K‐edge imaging.
The cerebral vasomotor response in varying CO2 concentrations, as evaluated using cine phase contrast MRI: Flow, volume, and cerebrovascular resistance indices
Authors: Liu Yi‐Jui , Huang Teng‐Yi , Lee Yi‐Hsiung , Juan Chun‐Jung
Published: October 2012

Purpose:

Previous studies have identified that impaired cerebral vasomotor reactivity (VMR) is associated with a higher risk of stroke and transient ischemic attack. This study aims to evaluate VMR by measuring the blood flow waveforms of the supplying arteries and dural sinuses using cine phase contrast MRI (PC MRI) and hypercapnic challenge.

Methods:

PC MRI flow quantification was performed on an oblique slice approximately perpendicular to the target vessels to include the left (LICA) and right internal carotid artery (RICA), basilar artery (BA), sinus rectus (SR), and superior sagittal sinus (SSS). A total of four PC MRI scans were performed at different CO2 concentrations (room air and 3%, 5%, and 7% CO2).

Results:

The analyses obtained the flow parameters and cerebrovascular resistance parameters for all five vessels. Results indicated that the vascular resistance indices decreased with increasing CO2 concentration in four vessels (LICA, RICA, BA, and SR). The obtained VMR parameters demonstrated exponential increases with increasing CO2 concentration.

Conclusions:

Using entire blood flow waveforms, this study applied separate flow dynamics during systolic and diastolic periods to obtain cerebrovascular resistance parameters and extensive flow‐related information. It is the first to investigate the cerebrovascular resistance parameters under hypercapnic challenge using cine MRI. This technique could provide a useful tool for clinical application in cerebrovascular disease.
A three-dimensional parabolic equation model of sound propagation using higher-order operator splitting and Padé approximants
Authors: Lin Ying-Tsong , Collis Jon M. , Duda Timothy F.
Published: October 2012

An alternating direction implicit (ADI) three-dimensional fluid parabolic equation solution method with enhanced accuracy is presented. The method uses a square-root Helmholtz operator splitting algorithm that retains cross-multiplied operator terms that have been previously neglected. With these higher-order cross terms, the valid angular range of the parabolic equation solution is improved. The method is tested for accuracy against an image solution in an idealized wedge problem. Computational efficiency improvements resulting from the ADI discretization are also discussed.
Is clear speech tailored to counter the effect of specific adverse listening conditions?
Authors: Hazan Valerie , Grynpas Jeremy , Baker Rachel
Published: October 2012

The study investigated the perception of speech produced to counter the effects of adverse listening conditions. Participants completed a problem-solving task with an interlocutor in good listening conditions (NB) or with the interlocutor hearing them via a vocoder (VOC) or babble (BAB). Keywords extracted from recordings were presented in babble for initial consonant identification. BAB tokens were identified faster than VOC or NB tokens even though VOC and BAB tokens were rated as similarly clear. Acoustic measures showed clarifications to be global rather than specifically enhancing phonological contrasts. These results suggest that clear speaking styles are tailored to listeners' needs.
Genome Sequence of Pectobacterium sp. Strain SCC3193
Authors: Koskinen J. Patrik , Laine Pia , Niemi Outi , Nykyri Johanna , Harjunpää Heidi , Auvinen Petri , Paulin Lars , Pirhonen Minna , Palva Tapio , Holm Liisa
Published: October 2012

We report the complete and annotated genome sequence of the plant-pathogenic enterobacterium
Pectobacterium
sp. strain SCC3193, a model strain isolated from potato in Finland. The
Pectobacterium
sp. SCC3193 genome consists of a 516,411-bp chromosome, with no plasmids.
Twenty-One Genome Sequences from Pseudomonas Species and 19 Genome Sequences from Diverse Bacteria Isolated from the Rhizosphere and Endosphere of Populus deltoides
Authors: Brown Steven D. , Utturkar Sagar M. , Klingeman Dawn M. , Johnson Courtney M. , Martin Stanton L. , Land Miriam L. , Lu Tse-Yuan S. , Schadt Christopher W. , Doktycz Mitchel J. , Pelletier Dale A.
Published: October 2012

To aid in the investigation of the
Populus deltoides
microbiome, we generated draft genome sequences for 21
Pseudomonas
strains and 19 other diverse bacteria isolated from
Populus deltoides
roots. Genome sequences for isolates similar to
Acidovorax
,
Bradyrhizobium
,
Brevibacillus
,
Caulobacter
,
Chryseobacterium
,
Flavobacterium
,
Herbaspirillum
,
Novosphingobium
,
Pantoea
,
Phyllobacterium
,
Polaromonas
,
Rhizobium
,
Sphingobium
, and
Variovorax
were generated.