bluuebunny/crossref_metadata_2025 huggingface dataset:
Highly Stable Duplex Formation by Artificial Nucleic Acids Acyclic Threoninol Nucleic Acid (aTNA) and Serinol Nucleic Acid (SNA) with Acyclic Scaffolds
Authors: Murayama Keiji , Tanaka Yoshihiro , Toda Takasuke , Kashida Hiromu , Asanuma Hiroyuki
Published: August 2013

The stabilities of duplexes formed by strands of novel artificial nucleic acids composed of acyclic threoninol nucleic acid (aTNA) and serinol nucleic acid (SNA) building blocks were compared with duplexes formed by the acyclic glycol nucleic acid (GNA), peptide nucleic acid (PNA), and native DNA and RNA. All acyclic nucleic acid homoduplexes examined in this study had significantly higher thermal stability than DNA and RNA duplexes. Melting temperatures of homoduplexes were in the order of aTNA>PNA≈GNA≥SNA≫RNA>DNA. Thermodynamic analyses revealed that high stabilities of duplexes formed by aTNA and SNA were due to large enthalpy changes upon formation of duplexes compared with DNA and RNA duplexes. The higher stability of the aTNA homoduplex than the SNA duplex was attributed to the less flexible backbone due to the methyl group of D‐threoninol on aTNA, which induced clockwise winding. Unlike aTNA, the more flexible SNA was able to cross‐hybridize with RNA and DNA. Similarly, the SNA/PNA heteroduplex was more stable than the aTNA/PNA duplex. A 15‐mer SNA/RNA was more stable than an RNA/DNA duplex of the same sequence.
Formation and Dynamic Behavior of Mono‐ and Bimetallic Cadmium(II) Porphyrin Complexes: Allosteric Control of Coupled Intraligand Metal Migrations
Authors: Le Gac Stéphane , Fusaro Luca , Dorcet Vincent , Boitrel Bernard
Published: August 2013

The complexation behavior of a bis‐strapped porphyrin ligand (1) towards CdII has been investigated by 1H and 113Cd NMR spectroscopy with the help of X‐ray diffraction structures. The presence of an overhanging carboxylic acid group on each side of the macrocycle is responsible for the instantaneous insertion of the metal ion(s) at room temperature, and allows the formation of bimetallic species with unusual coordination modes at the origin of unique dynamic behaviors. In the absence of base, a C2‐symmetric bimetallic complex (1Cd2) is readily formed, in which the porphyrin acts as a bridging ligand. Both CdII ions are bound to the N core and to a COO− group of a strap. In contrast, the presence of a base induces a two‐step binding process with the successive formation of mono and bimetallic species (1Cd and 1Cd⋅CdOAc). Formally, a CdII ion is first inserted into the N core and experiences a strong out‐of‐plane (OOP) displacement due to the binding of an overhanging carbonyl group in an apical position. A second CdII ion then binds exclusively to the strap on the opposite side, in a so‐called hanging‐atop (HAT) coordination mode. These two complexes display a fluxional behavior that relies on intraligand migration processes of the metal ion(s). In 1Cd, the CdII ion exchanges between the two equivalent overhanging apical ligands by funneling through the porphyrin ring. In 1Cd⋅CdOAc, the two CdII ions exchange their coordination mode (HAT↔OOP) in a concerted way while staying on their respective side of the macrocycle, in a so‐called Newton’s cradle‐like motion. The intramolecular pathway was notably evidenced by variable temperature 113Cd heteronuclear NMR experiments. This coupled motion of the CdII cations is under allosteric control; the addition of an acetate anion (the allosteric effector) to the “resting” C2‐symmetric complex 1Cd2 affords the dissymmetric complex 1Cd⋅CdOAc and triggers equilibrium between its two degenerate states. The rate of the swinging motion further depends on the concentration of AcO−, with a higher concentration leading to a slower motion. As compared with the related PbII and BiIII bimetallic complexes, the Newton’s cradle‐like motion proceeds faster with the smaller CdII ion. These results open the way to novel multistable devices and switches.
Effect of Phosphate Modification on the Brønsted Acidity and Methanol‐to‐Olefin Conversion Activity of Zeolite ZSM‐5
Authors: Dyballa Michael , Klemm Elias , Weitkamp Jens , Hunger Michael
Published: August 2013

Phosphate‐modified ZSM‐5 zeolites were studied by standard characterization techniques and solid‐state nuclear magnetic resonance spectroscopy, and in the methanol‐to‐olefin (MTO) conversion. Considering the physicochemical properties of the ZSM‐5 zeolites, the most important effects of the phosphate modification are a deposition of polyphosphates in the pore system and a decrease of the acid site density, but not of the acid site strength. The significant increase in the selectivity to C2 – C4 alkenes and the decrease of C5+ formation in the MTO reaction for a phosphate coverage of about 5 wt % are explained by extra‐framework phosphate species near the crossing intersections of the ZSM‐5 pore system, which hinder the formation of large intermediates and reaction products.
Variation of Pseudomonas aeruginosa in Rainwater Harvesting Systems: Effects of Seasons, Catchments and Storage Conditions
Authors: Nawaz Mohsin , Amin Muhammad Tahir , Han Mooyoung , Alazba Abdulrahman Ali , Manzoor Umair , Amin Muhammad Nasir
Published: August 2013

The effects of different catchment types and storage conditions on Pseudomonas aeruginosa in harvested rainwater under wet and dry seasons were investigated. Both horizontal (roof intercepted to outlet point) and vertical (surface to bottom) quality variation inside storage tanks of different rainwater harvesting (RWH) systems was also monitored. The numbers of P. aeruginosa varied from 30 to 400 colony forming units (CFU)/100 mL during the dry season and 200 to 1800 CFU/100 mL during the wet season. A relatively good quality of harvested rainwater was observed in dry season. The horizontal and vertical quality variation of P. aeruginosa revealed best quality at the supply point. The number of P. aeruginosa was the highest (about 1800 and 1000 CFU/100 mL during wet and dry seasons, respectively) in rainwater harvested from mountain catchment while the lowest (about 30 and 1000 CFU/100 mL during dry and wet seasons, respectively) numbers was seen from concrete roof catchment. Dark, covered storage conditions resulting low rainwater temperatures showed better microbial quality of rainwater than uncovered and open storage conditions exposed to light. The study suggests that the improvement in the quality of harvested rainwater is possible when appropriate tank designs, maintenance of catchment surfaces, and proper storage conditions are considered in RWH systems.
Preservation of neurocognitive function and local control of 1 to 3 brain metastases treated with surgery and carmustine wafers
Authors: Brem Steven , Meyers Christina A. , Palmer Gary , Booth‐Jones Margaret , Jain Surbhi , Ewend Matthew G.
Published: August 2013

BACKGROUND

Neurosurgical resection and whole‐brain radiation therapy (WBRT) are accepted treatments for single and oligometastatic cancer to the brain. To avoid the decline in neurocognitive function (NCF) linked to WBRT, the authors conducted a prospective, multicenter, phase 2 study to determine whether surgery and carmustine wafers (CW), while deferring WBRT, could preserve NCF and achieve local control (LC).

METHODS

NCF and LC were measured in 59 patients who underwent resection and received CW for a single (83%) or dominant (oligometastatic, 2 to 3 lesions) metastasis and received stereotactic radiosurgery (SRS) for tiny nodules not treated with resection plus CW. Preservation of NCF was defined as an improvement or a decline ≤1 standard deviation from baseline in 3 domains: memory, executive function, and fine motor skills, evaluated at 2‐month intervals.

RESULTS

Significant improvements in executive function and memory occurred throughout the 1‐year follow‐up. Preservation or improvement of NCF occurred in all 3 domains for the majority of patients at each of the 2‐month intervals. NCF declined in only 1 patient. The chemowafers were well tolerated, and serious adverse events were reversible. There was local recurrence in 28% of the patients at 1‐year follow‐up.

CONCLUSIONS

Patients with brain metastases had improvements in their cognitive trajectory, especially memory and executive function, after treatment with resection plus CW. The rate of LC (78%) was comparable to historic rates of surgery with WBRT and superior to reports of WBRT alone. For patients who undergo resection for symptomatic or large‐volume metastasis or for tissue diagnosis, the addition of CW can be considered as an option. Cancer 2013;119:3830–3838. © 2013 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society.
Rapid on‐site evaluation for endoscopic ultrasound‐guided fine‐needle biopsy of the pancreas decreases the incidence of repeat biopsy procedures
Authors: Collins Brian T. , Murad Faris M. , Wang Jeff F. , Bernadt Cory T.
Published: August 2013

BACKGROUND

Rapid on‐site evaluation (ROSE) for endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) biopsy of the pancreas provides immediate feedback regarding cellular adequacy to aid in obtaining a definitive diagnosis and has the potential to avoid repeat procedures. The objective of the current study was to measure the impact of ROSE service on the incidence of repeat EUS FNA biopsy procedures.

METHODS

Over a consecutive 3‐year period, the pathology database at Washington University Medical Center was searched for patients with both an initial and subsequent EUS FNA biopsy demonstrating a solid lesion of the pancreas. These were divided temporally between the time before and after the introduction of ROSE service. Reports were reviewed and results were recorded.

RESULTS

A total of 379 patients underwent ROSE service and 377 patients did not. The percentage of repeat non‐ROSE EUS FNA cases was 5.8% and the percentage of repeat ROSE EUS FNA cases was 2.9%. The use of the ROSE service was found to decrease the number of repeat procedures by approximately 50% (P = .024). For those patients who underwent a repeat EUS‐FNA procedure, the ROSE service provided a higher rate of definitive diagnosis among patients undergoing repeat procedures (67%) versus the non‐ROSE cohort (27%).

CONCLUSIONS

The use of ROSE for EUS‐FNA biopsy of the pancreas was found to result in fewer patients undergoing repeat procedures. Patients who required a repeat procedure with the use of ROSE had a higher percentage of definitive diagnostic categorization on the repeat biopsy. Initial use of ROSE for EUS‐FNA of solid pancreatic lesions was found to decrease the number of patients who required a repeat procedure. Cancer (Cancer Cytopathol) 2013;121:518–24. © 2013 American Cancer Society.
Tanycyte‐like cells form a blood–cerebrospinal fluid barrier in the circumventricular organs of the mouse brain
Authors: Langlet Fanny , Mullier Amandine , Bouret Sebastien G. , Prevot Vincent , Dehouck Benedicte
Published: August 2013

Tanycytes are highly specialized ependymal cells that form a blood–cerebrospinal fluid (CSF) barrier at the level of the median eminence (ME), a circumventricular organ (CVO) located in the tuberal region of the hypothalamus. This ependymal layer harbors well‐organized tight junctions, a hallmark of central nervous system barriers that is lacking in the fenestrated portal vessels of the ME. The displacement of barrier properties from the vascular to the ventricular side allows the diffusion of blood‐borne molecules into the parenchyma of the ME while tanycyte tight junctions control their diffusion into the CSF, thus maintaining brain homeostasis. In the present work, we combined immunohistochemical and permeability studies to investigate the presence of tanycyte barriers along the ventricular walls of other brain CVOs. Our data indicate that, unlike cuboidal ependymal cells, ependymal cells bordering the CVOs possess long processes that project into the parenchyma of the CVOs to reach the fenestrated capillary network. Remarkably, these tanycyte‐like cells display well‐organized tight junctions around their cell bodies. Consistent with these observations, permeability studies show that this ependymal layer acts as a diffusion barrier. Together, our results suggest that tanycytes are a characteristic feature of all CVOs and yield potential new insights into their involvement in regulating the exchange between the blood, the brain, and the CSF within these “brain windows.” J. Comp. Neurol. 521:3389‐3405, 2013. © 2013 Wiley Periodicals, Inc.
Brain‐derived neurotrophic factor: mRNA expression and protein distribution in the brain of the teleost Nothobranchius furzeri
Authors: D'Angelo Livia , De Girolamo Paolo , Lucini Carla , Terzibasi Eva Tozzini , Baumgart Mario , Castaldo Luciana , Cellerino Alessandro
Published: August 2013

BDNF (brain‐derived neurotrophic factor) is a member of the neurotrophin family and it is implicated in regulating brain development and function. The BDNF gene organization and coding sequence are conserved in all vertebrates. The present survey was conducted in a teleost fish, Nothobranchius furzeri, because it is an emerging model of aging studies due to its short lifespan and shows the high rate of adult neurogenesis typical of anamniotes. The present survey reports: 1) the identification and characterization of the cDNA fragment encoding BDNF protein, and 2) the localization of BDNF in the whole brain. BDNF mRNA expression was assessed by in situ hybridization, by employing an antisense RNA probe; BDNF protein was detected by employing a sensitive immunohistochemical technique, along with highly specific affinity‐purified antibodies to BDNF. Both BDNF mRNA and protein were detected in neurons and glial cells of all regions of the brain of N. furzeri. Interestingly, BDNF was localized also in brain areas involved in adult neurogenic activities, suggesting a specific role for this neurotrophic factor in controlling cell proliferation. These results provide baseline information for future studies concerning BDNF involvement in the aging processes of the teleost brain. J. Comp. Neurol. 522:1004–1030, 2014. © 2013 Wiley Periodicals, Inc.
Anatomy of hierarchy: Feedforward and feedback pathways in macaque visual cortex
Authors: Markov Nikola T. , Vezoli Julien , Chameau Pascal , Falchier Arnaud , Quilodran René , Huissoud Cyril , Lamy Camille , Misery Pierre , Giroud Pascale , Ullman Shimon , Barone Pascal , Dehay Colette , Knoblauch Kenneth , Kennedy Henry
Published: August 2013

The laminar location of the cell bodies and terminals of interareal connections determines the hierarchical structural organization of the cortex and has been intensively studied. However, we still have only a rudimentary understanding of the connectional principles of feedforward (FF) and feedback (FB) pathways. Quantitative analysis of retrograde tracers was used to extend the notion that the laminar distribution of neurons interconnecting visual areas provides an index of hierarchical distance (percentage of supragranular labeled neurons [SLN]). We show that: 1) SLN values constrain models of cortical hierarchy, revealing previously unsuspected areal relations; 2) SLN reflects the operation of a combinatorial distance rule acting differentially on sets of connections between areas; 3) Supragranular layers contain highly segregated bottom‐up and top‐down streams, both of which exhibit point‐to‐point connectivity. This contrasts with the infragranular layers, which contain diffuse bottom‐up and top‐down streams; 4) Cell filling of the parent neurons of FF and FB pathways provides further evidence of compartmentalization; 5) FF pathways have higher weights, cross fewer hierarchical levels, and are less numerous than FB pathways. Taken together, the present results suggest that cortical hierarchies are built from supra‐ and infragranular counterstreams. This compartmentalized dual counterstream organization allows point‐to‐point connectivity in both bottom‐up and top‐down directions. J. Comp. Neurol. 522:225–259, 2014. © 2013 Wiley Periodicals, Inc.
Protracted maturation of forebrain afferent connections of the ventral tegmental area in the rat
Authors: Yetnikoff Leora , Reichard Rhett A. , Schwartz Zachary M. , Parsely Kenneth P. , Zahm Daniel S.
Published: August 2013

The mesocorticolimbic dopamine system has long attracted the interest of researchers concerned with the unique gamut of behavioral and mental health vulnerabilities associated with adolescence. Accordingly, the development of the mesocorticolimbic system has been studied extensively, but almost exclusively with regard to dopaminergic output, particularly in the nucleus accumbens and medial prefrontal cortex. To the contrary, the ontogeny of inputs to the ventral tegmental area (VTA), the source of mesocorticolimbic dopamine, has been neglected. This is not a trivial oversight, as the activity of VTA neurons, which reflects their capacity to transmit information about salient events, is sensitively modulated by inputs. Here, we assessed the development of VTA afferent connections using the β subunit of cholera toxin (Ctβ) as a retrograde axonal tracer in adolescent (postnatal day 39) and early adult (8–9‐week‐old) rats. After intra‐VTA injections of Ctβ, adolescent and early adult animals exhibited qualitatively similar distributions of retrogradely labeled neurons in the sense that VTA‐projecting neurons were present at all of the same rostrocaudal levels in all of the same structures in both age groups. However, quantitation of retrogradely labeled neurons revealed that adolescent brains, compared with early adult brains, had significantly fewer VTA‐projecting neurons preferentially within an interconnected network of cortical and striatopallidal forebrain structures. These findings provide a novel perspective on the development of the mesocorticolimbic dopamine system and may have important implications for age‐dependent specificity in the function of this system, particularly with regard to adolescent impulsivity and mental health vulnerabilities. J. Comp. Neurol. 522:1031–1047, 2014. © 2013 Wiley Periodicals, Inc.
Distinctive population of Gfap‐expressing neural progenitors arising around the dentate notch migrate and form the granule cell layer in the developing hippocampus
Authors: Seki Tatsunori , Sato Toru , Toda Keiko , Osumi Noriko , Imura Tetsuya , Shioda Seiji
Published: August 2013

In the adult hippocampus, granule cells continue to be generated from astrocyte‐like progenitors expressing glial fibrillary acidic protein (GFAP) that differ from embryonic neocortical progenitors. However, during the embryonic period, dentate granule neurons and neocortical pyramidal neurons are derived from the ventricular zone (VZ) of the pallium. Our question is when do GFAP+ progenitors of granule neurons appear in the developing hippocampus during the embryonic period, and how do they form the granule cell layer. The present analysis using Gfap‐GFP transgenic mice shows that the GFP+ distinct cell population first appears in the VZ of the medial pallium at the dorsal edge of the fimbria on embryonic day 13.5. During the perinatal period, they form a migratory stream from the VZ to the developing dentate gyrus, and establish the germinal zones in the migratory stream, and the marginal and hilar regions in the developing dentate gyrus. GFP+ cells in these regions were positive for Sox2 and Ki67, but negative for BLBP. GFP+ cells with Neurogenin2 expression were largely distributed in the VZ, whereas GFP+ cells with Tbr2 and NeuroD expressions were seen in the migratory stream and developing dentate gyrus. Prox1‐expressing GFP+ cells were restricted to the developing dentate gyrus. These results suggest that distinctive Gfap‐expressing progenitors arising around the dentate notch form germinal regions in the migratory stream and the developing dentate gyrus where they differentiate into granule neurons, indicating that distinct astrocyte‐like neural progenitors continue to generate granule neurons, from the beginning of dentate development and throughout life. J. Comp. Neurol. 522:261–283, 2014. © 2013 Wiley Periodicals, Inc.
Should diabetic ketosis without acidosis be included in ketosis‐prone type 2 diabetes mellitus?
Authors: Xie Xiao‐Jing , Hu Yun , Cheng Cheng , Feng Tian‐Tian , He Ke , Mao Xiao‐Ming
Published: August 2013

Background

The incidence of ketosis‐prone type 2 diabetes is very low except for people of sub‐Saharan African origin and African Americans. However, there also are some type 2 diabetes patients with diabetic ketosis without acidosis (DKWA). We question whether DKWA should be included as a subtype of ketosis‐prone type 2 diabetes mellitus and compared the clinical characteristics of DKWA and diabetic ketoacidosis (DKA) patients.

Methods

The study population consisted of 594 consecutive unrelated Chinese inpatients with newly diagnosed type 2 diabetes. Demographic and clinical characteristics (age, gender, family history of diabetes, body mass index, blood pressure and plasma lipid parameters) were recorded. The patients were divided into ketosis‐resistant diabetes (KRD), DKWA and DKA groups on the basis of urinary ketones, blood pH and bicarbonate levels. The blood glucose and c‐peptide levels of the patients were also evaluated.

Results

The prevalence of KRD, DKWA and DKA were 78.33%, 19.72% and 1.95%, respectively, in the study population. The clinical characteristics of patients with DKWA group patients were similar to those with DKA, except that DKA patients had higher blood glucose and deteriorated β cell function.

Conclusions

Diabetic ketosis without acidosis and DKA patients share similar clinical characteristics; DKWA should be considered ketosis‐prone type 2 diabetes. Therefore, the prevalence of ketosis‐prone type 2 diabetes might be underestimated. Copyright © 2013 John Wiley & Sons, Ltd.
Construction of Enantioenriched Cyclic Compounds by Asymmetric Allylic Alkylation and Ring‐Closing Metathesis
Authors: Giacomina Francesca , Alexakis Alexandre
Published: August 2013

A new approach to highly enantioenriched cyclic compounds (up to 98 % ee) has been developed by using ω‐ethylenic allylic substrates in a one‐pot asymmetric allylic alkylation and ring‐closing metathesis sequence. The starting compounds are synthetic equivalents of cyclic allylic substrates. The method is exemplified with both Cu and Ir catalysts, and chiral phosphoramidite ligands.
Fuel‐mix and energy utilization analysis of Port Harcourt Refining Company, Nigeria
Authors: Badmus Ismaila , Fagbenle Richard Olayiwola , Oyewola Olanrewaju Miracle
Published: August 2013

This study analyses the fuel‐mix and energy utilization patterns in Port Harcourt Refining Company from 2000 to 2011. The average fuel mix over the study period is 43% refinery fuel gas, 0% liquefied petroleum gas (LPG), 44% low pour fuel oil (LPFO), 8% Coke, and 5% automotive gas oil (AGO). The present ratio of high‐carbon fuel consumption to low‐carbon fuel consumption adversely influences the specific fuel consumption by increasing it. Our proposal is that the present AGO and LPFO consumption levels are totally replaced with equivalent amounts of natural gas. This would yield the following fuel mix: 46% refinery fuel gas, 46% natural gas, and 8% coke. This, in effect, would result in a proportion of 92% low‐carbon fuels and 8% coke. It would also lead to a specific fuel consumption that is averagely unaffected by high‐carbon/low‐carbon fuel consumption ratios. Natural gas utilization has its main advantage in its flare/waste and consequent environmental degradation reduction. Finally, the proposed fuel mix would generally lead to a reduction in specific fuel consumption, thus saving energy and reducing costs.
Recent variation in reach‐scale bankfull discharge in the Lower Yellow River
Authors: Xia Junqiang , Li Xiaojuan , Zhang Xiaolei , Li Tao
Published: August 2013

Bankfull discharge is a key parameter in the context of river engineering and geomorphology, as an indicator of flood discharge capacity in alluvial rivers, and varying in response to the incoming flow and sediment regimes. Bankfull channel dimensions have significantly adjusted along the Lower Yellow River (LYR) due to recent channel degradation, caused by the operation of the Xiaolangdi Reservoir, which has led to longitudinal variability in cross‐sectional bankfull discharges. Therefore, it is more representative to describe the flood discharge capacity of the LYR, using the concept of reach‐averaged bankfull discharge. Previous simple mean methods to estimate reach‐scale bankfull discharge cannot meet the condition of flow continuity or account for the effect of different spacing between two sections. In this study, a general method to calculate cross‐sectional bankfull discharge using the simulated stage‐discharge relation is outlined briefly, and an integrated method is then proposed for estimating reach‐scale bankfull discharge. The proposed method integrates a geometric mean based on the log‐transformation with a weighted average based on the spacing between two consecutive sections, which avoids the shortcomings of previous methods. The post‐flood reach‐scale bankfull discharges in three different channel‐pattern reaches of the LYR were estimated annually during the period from 1999 to 2010 using the proposed method, based on surveyed post‐flood profiles at 91 sedimentation sections and the measured hydrological data at seven hydrometric sections. The calculated results indicate that: (i) the estimated reach‐scale bankfull discharges can effectively represent the flood discharge capacity of different reaches, with their ranges of variation being less than those of typical cross‐sectional bankfull discharges; and (ii) the magnitude of the reach‐scale bankfull discharge in each reach can respond well to the accumulative effect of incoming flow and sediment conditions. Finally, empirical relationships for different reaches in the LYR were developed between the reach‐scale bankfull discharge and the previous four‐year average discharge and incoming sediment coefficient during flood seasons, with relatively high correlation coefficients between them being obtained, and the reach‐scale bankfull discharges in different reaches predicted by the delayed response model were also presented for a comparison. These relations for the prediction of reach‐scale bankfull discharges were validated using the cross‐sectional profiles and hydrological data measured in 2011. Copyright © 2013 John Wiley & Sons, Ltd.
Potentiating toxicological interaction of single-walled carbon nanotubes with dissolved metals
Authors: Al-Shaeri Majed , Ahmed Dina , McCluskey Fiona , Turner Gavin , Paterson Lynn , Dyrynda Elisabeth A. , Hartl Mark G.J.
Published: August 2013

The present study explored the ecotoxicology of single-walled carbon nanotubes (SWCNTs) and their likely interaction with dissolved metals, with a focus on the effect of in vivo exposure in marine mussels. Any nano-scale effects were negated by the tendency of uncoated SWCNTs to agglomerate in water, particularly with high ionic strength as is the case in estuarine and full-strength seawater. However, SWCNTs, in combination with natural organic matter, remained suspended in seawater for long enough to become available to filter-feeding mussels, leading to their concentration on and increased contact with gill epithelia during exposure. For the first time, the authors describe a potentiating toxicological effect, expressed as DNA strand breaks obtained using the comet assay, on divalent metals afforded by negatively charged SWCNT agglomerates in seawater at concentrations as low as 5 µg L−1. This is supported by the observation that SWCNTs alone were only toxic at concentrations ≥100 µg L−1 and that the SWCNT-induced DNA damage was correlated with oxidative stress only in the absence of metals. If these laboratory experiments are confirmed in the natural environment, the present results will have implications for the understanding of the role of carbon nanotubes in environmental metal dynamics, toxicology, and consequently, regulatory requirements. Environ Toxicol Chem 2013;32:2701–2710. © 2013 SETAC
Anopheles arabiensis egg treatment with dieldrin for sex separation leaves residues in male adult mosquitoes that can bioaccumulate in goldfish (Carassius auratus auratus)
Authors: Yamada Hanano , Jandric Zora , Chhem-Kieth Sorivan , Vreysen Marc J.B. , Rathor Mohammad N. , Gilles Jeremie R.L. , Cannavan Andrew
Published: August 2013

The sterile insect technique (SIT) is a biological control tactic that is used as a component of area-wide integrated pest management (AW-IPM) programs. The SIT can only be applied against disease-transmitting mosquitoes when only sterile male mosquitoes are released, and the blood-sucking and potentially disease-transmitting females are eliminated from the production line. For Anopheles arabiensis, a potent vector of malaria, a genetic sexing strain was developed whereby females can be eliminated by treating the eggs or larvae with the insecticide dieldrin. To evaluate the presence of dieldrin residues in male mosquitoes designated for SIT releases, a simple, sensitive, and accurate gas chromatography–electron capture detector (GC–ECD) method was developed. In addition, bioaccumulation and food chain transfer of these residues to fish after feeding with treated mosquitoes was demonstrated. The overall recovery from method validation studies was 77.3 ± 2.2% (mean ± relative standard deviation [RSD]) for the mosquitoes, and 99.1 ± 4.4% (mean ± RSD) for the fish. The average dieldrin concentration found in adult male An. arabiensis was 28.1 ± 2.9 µg/kg (mean ± standard deviation [SD]). A range of 23.9 ± 1.1 µg/kg to 73.9 ± 5.2 µg/kg (mean ± SD) of dieldrin was found in the fish samples. These findings indicate the need to reassess the environmental and health implications of control operations with a SIT component against An. arabiensis that involves using persistent organochlorines in the sexing process. Environ Toxicol Chem 2013;32:2786–2791. © 2013 IAEA. Environmental Toxicology and Chemistry Published by Wiley Periodicals, Inc. on behalf of SETAC. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution, and reproduction in any medium, provided the original work is properly cited.
Effects of 17α-ethynylestradiol, fluoxetine, and the mixture on life history traits and population growth rates in a freshwater gastropod
Authors: Luna Tamara O. , Plautz Stephanie C. , Salice Christopher J.
Published: August 2013

Pharmaceutical and personal care products (PPCPs), some of which have endocrine-disrupting effects at environmentally relevant concentrations, have been detected in many surface waters. The authors evaluated the effects of 2 common endocrine disrupting PPCPs on the life history traits of the snail, Physa pomilia, using a life table response experiment with snails raised in environmentally relevant concentrations of 17α-ethynylestradiol (EE2), fluoxetine, or their mixture. Exposure to fluoxetine or the mixture reduced snail reproduction, but EE2 did not. Generally, individual life history traits were affected minimally by the PPCPs, but when integrated using a demographic model, all 3 chemical exposure scenarios decreased population growth rates, with the EE2 and fluoxetine mixture causing the most adverse effects. Overall, the results provide additional insight into the effects of PPCPs on freshwater invertebrates and point to the importance of testing simultaneous exposures to multiple PPCPs. In addition, using a demographic model to integrate individual endpoints provided insights into effects that were not apparent from individual life history traits alone and suggest at least a potential for adverse ecological effects under realistic environmental exposures concentrations. Environ Toxicol Chem 2013;32:2771–2778. © 2013 SETAC
Improving sediment-quality guidelines for nickel: Development and application of predictive bioavailability models to assess chronic toxicity of nickel in freshwater sediments
Authors: Vangheluwe Marnix L.U. , Verdonck Frederik A.M. , Besser John M. , Brumbaugh William G. , Ingersoll Christopher G. , Schlekat Christan E. , Garman Emily Rogevich
Published: August 2013

Within the framework of European Union chemical legislations an extensive data set on the chronic toxicity of sediment nickel has been generated. In the initial phase of testing, tests were conducted with 8 taxa of benthic invertebrates in 2 nickel-spiked sediments, including 1 reasonable worst-case sediment with low concentrations of acid-volatile sulfide (AVS) and total organic carbon. The following species were tested: amphipods (Hyalella azteca, Gammarus pseudolimnaeus), mayflies (Hexagenia sp.), oligochaetes (Tubifex tubifex, Lumbriculus variegatus), mussels (Lampsilis siliquoidea), and midges (Chironomus dilutus, Chironomus riparius). In the second phase, tests were conducted with the most sensitive species in 6 additional spiked sediments, thus generating chronic toxicity data for a total of 8 nickel-spiked sediments. A species sensitivity distribution was elaborated based on 10% effective concentrations yielding a threshold value of 94 mg Ni/kg dry weight under reasonable worst-case conditions. Data from all sediments were used to model predictive bioavailability relationships between chronic toxicity thresholds (20% effective concentrations) and AVS and Fe, and these models were used to derive site-specific sediment-quality criteria. Normalization of toxicity values reduced the intersediment variability in toxicity values significantly for the amphipod species Hyalella azteca and G. pseudolimnaeus, but these relationships were less clearly defined for the mayfly Hexagenia sp. Application of the models to prevailing local conditions resulted in threshold values ranging from 126 mg to 281 mg Ni/kg dry weight, based on the AVS model, and 143 mg to 265 mg Ni/kg dry weight, based on the Fe model. Environ Toxicol Chem 2013;32:2507–2519. © 2013 SETAC
Preparation and olfactory evaluation of mono‐ and bicyclic compounds featuring gem‐dimethylcyclohexane structures
Authors: Godeau Julien , Grau Fanny , Antoniotti Sylvain , Duñach Elisabet
Published: August 2013

A series of non‐conjugated dienic and trienic diester derivatives was catalytically cyclized and the ester and ethylenic moieties were further transformed into several functional groups. Olfactory evaluation of the compound series featuring gem‐dimethyl and isopropenyl motifs presents woody and fruity aspects as the main notes. Copyright © 2013 John Wiley & Sons, Ltd.
A novel nonreflecting boundary condition for unsteady flow
Authors: Zafer Baha , Delale Can F.
Published: August 2013

A novel nonreflecting boundary condition, which converges to the specified time‐dependent boundary condition within any degree of accuracy, is introduced for the numerical simulation of hyperbolic systems and validated against the solution of two fundamental boundary value problems in fluids. First, transonic nozzle flow with backward acoustic disturbance is considered. Using high‐order aeroacoustic numerical schemes, the proposed nonreflecting boundary condition yields results that are in excellent agreement with those obtained using conventional nonreflecting boundary conditions based on the method of characteristics as well as with the results of the exact solution. The novel nonreflecting boundary condition, implemented into a semi‐analytical solution algorithm of unsteady bubbly cavitating nozzle flows, is also validated against results obtained using a Lagrangian finite volume scheme. Copyright © 2013 John Wiley & Sons, Ltd.
Climatologic and hydrologic influences on the oxygen isotope ratio of tree cellulose in coastal southern California during the late 20th century
Authors: Kanner Lisa , Buenning Nikolaus , Stott Lowell , Stahle Dave
Published: August 2013

The oxygen isotope ratio (δ18O) of precipitation in continental, midlatitude regions is a complex measure of atmospheric dynamics and regional climate variability and can be preserved in geologic archives. However, continuous modern observations of precipitation δ18O in many midlatitude regions, particularly in the coastal western United States, are sparse. Here, tree‐ring cellulose δ18O from southern California is used to assess the potential of this proxy as an indicator of long‐term hydroclimate and atmospheric variability. From 1954 to 2004, we observed that cellulose δ18O was well replicated within a single stand of blue oak (Quercus douglasii) on interannual and decadal time scales. By using a forward mechanistic model, we demonstrate that cellulose δ18O is not driven solely by the oxygen isotope composition of precipitation at the site nor any other single hydroclimate variable. Instead, the interannual variability in cellulose δ18O prior to 1979 is positively correlated with growing season soil water δ18O and after 1979 is negatively correlated with relative humidity. In addition, 2 years (1983 and 1998) of anomalously low cellulose δ18O coincided with the wettest years in California and the strongest El Niño events of the late 20th century. For these years, decreased near surface evaporation and/or increased upper‐level condensation could account for the more depleted cellulose δ18O values. While blue oak cellulose δ18O is sensitive to atmospheric and hydroclimate variability, the varying temporal correlation between the cellulose δ18O and different environmental variables complicates any attempt to use the cellulose oxygen isotopes for reconstructions of climate variability beyond the calibration period.
Discovery of two distinct types of equatorial 150 km radar echoes
Authors: Chau J. L. , Kudeki E.
Published: August 2013

We show here that VHF signals scattered from the 150 km region above Jicamaca exhibit two distinct types of features. In one type (type A), the Doppler spectral width increases with the echo strength and the corresponding signal‐to‐noise ratio (SNR). A second type (type B) of higher SNR echoes exhibits SNR‐independent Doppler spectral widths that are much narrower than those observed in the first type. The type A echo population is by far the dominant population. Comparisons with earlier data sets collected at Jicamarca and elsewhere suggest that the type A and type B are likely to be associated with a naturally enhanced incoherent scattering (NEIS) process and the unstable growth of field‐aligned irregularities (FAIs), respectively. We conjecture that small radar systems operated near the geomagnetic equator that have reported 150 km echo observations detected FAI echoes and that the NEIS echoes can only be seen by high sensitivity systems.
Low Arabian dust extinction‐to‐backscatter ratio
Authors: Mamouri R. E. , Ansmann A. , Nisantzi A. , Kokkalis P. , Schwarz A. , Hadjimitsis D.
Published: August 2013

Compared to typical values of 50–60 sr of the extinction‐to‐backscatter ratio (lidar ratio) at 532 nm of western Saharan mineral dust, low dust lidar ratios from 33.7±6.7 to 39.1±5.1 sr were derived from polarization lidar observations at Limassol, Cyprus (34°N, 33°E) during an outbreak of Arabian dust mainly from Syria in September 2011, indicated by particle linear depolarization ratios up to 28%–35%. The applied new polarization‐lidar/photometer method for the extraction of the dust‐related lidar‐ratio information from the lidar data is outlined, and the results of the dust outbreak which lasted over several days are discussed. The results confirm an Aerosol Robotic Network photometer study on Arabian dust lidar ratios.
Tomographic image of melt storage beneath Askja Volcano, Iceland using local microseismicity
Authors: Mitchell Michael A. , White Robert S. , Roecker Steve , Greenfield Tim
Published: August 2013

We use P wave and S wave arrivals from microseismic earthquakes to construct 3‐D tomographic Vp and Vs images of the magma storage region beneath Askja's central volcano in the Northern Volcanic Zone of Iceland. A distinctive ellipsoidal low‐velocity anomaly, with both Vp and Vsvelocities 8‐12% below the background, is imaged at 6‐11 km depth beneath the caldera. The presence of a shallow magma chamber is corroborated by geodetic and gravity studies. The small Vp/Vs anomaly suggests a lack of pervasive melt. We interpret this anomaly as a region of multiple sills, some frozen but hot, others containing partial melt. A second, smaller low‐velocity anomaly beneath the main magma storage region may represent a magma migration pathway. This interpretation is supported by the close proximity to the anomaly of clusters of deep, magmatically induced earthquakes. However, the location and shape of this deep anomaly are poorly constrained by the current data set.
Action observers implicitly expect actors to act goal‐coherently, even if they do not: An fMRI study
Authors: Hrkać Mari , Wurm Moritz F. , Schubotz Ricarda I.
Published: August 2013

Actions observed in everyday life normally consist of one person performing sequences of goal‐directed actions. The present fMRI study tested the hypotheses that observers are influenced by the actor's identity, even when this information is task‐irrelevant, and that this information shapes their expectation on subsequent actions of the same actor. Participants watched short video clips of action steps that either pertained to a common action with an overarching goal or not, and were performed by either one or by varying actors (2 × 2 design). Independent of goal coherence, actor coherence elicited activation in dorsolateral and ventromedial frontal cortex, together pointing to a spontaneous attempt to integrate all actions performed by one actor. Interestingly, watching an actor performing unrelated actions elicited additional activation in left inferior frontal gyrus, suggesting a search in semantic memory in an attempt to construct an overarching goal that can reconcile the disparate action steps with a coherent intention. Post‐experimental surveys indicate that these processes occur mostly unconsciously. Findings strongly suggest a spontaneous expectation bias toward actor‐related episodes in action observers, and hence to the immense impact of actor information on action observation. Hum Brain Mapp 35:2178–2190, 2014. © 2013 Wiley Periodicals, Inc.
ATP‐binding cassette transporters and cholesterol translocation
Authors: Li Ge , Gu Hong‐Mei , Zhang Da‐Wei
Published: August 2013

Cholesterol, a major component of mammalian cell membranes, plays important structural and functional roles. However, accumulation of excessive cholesterol is toxic to cells. Aberrant cholesterol trafficking and accumulation is the molecular basis for many diseases, such as atherosclerotic cardiovascular disease and Tangier's disease. Accumulation of excessive cholesterol is also believed to contribute to the early onset of Alzheimer's disease. Thus, cellular cholesterol homeostasis is tightly regulated by uptake, de novo synthesis, and efflux. Any surplus of cholesterol must either be stored in the cytosol in the form of esters or released from the cell. Recently, several ATP‐binding cassette (ABC) transporters, such as ABCA1, ABCG1, ABCG5, and ABCG8 have been shown to play important roles in the regulation of cellular cholesterol homeostasis by mediating cholesterol efflux. Mutations in ABC transporters are associated with several human diseases. In this review, we discuss the physiological roles of ABC transporters and the underlying mechanisms by which they mediate cholesterol translocation. © 2013 IUBMB Life, 65(6):505–512, 2013
Musculoskeletal pain and physical functioning in the oldest old
Authors: Mänty M. , Thinggaard M. , Christensen K. , Avlund K.
Published: August 2013

Background

Little is known about the impact of pain on physical functioning among the oldest‐old subjects. In this study, we first examined the associations between the number of painful sites and measures of physical functioning reflecting different stages of the disablement process (physical impairment, functional limitation and disability) among nonagenarians (more than ninety years old persons). Second, we described the effect of painful sites on disability during a 2‐year follow‐up period.

Methods

This study is based on baseline (n = 1177) and 2‐year follow‐up (n = 709) data of the nationwide Danish 1905 cohort study. Musculoskeletal pain was assessed as reported pain in back, hips or knees when moving or resting. Physical performance measures included maximum grip strength and habitual walking speed. Disability in performing activities of daily living was defined as the need for assistive device or personal help in transferring, dressing, washing, using toilet and/or walking indoors.

Results

At baseline, the number of painful sites was significantly associated with measured grip strength and walking speed as well as self‐reported disability in a stepwise manner; the more sites with pain, the poorer the physical functioning. The follow‐up analyses showed corresponding but slightly weaker stepwise associations between baseline pain and disability level at follow‐up, and indicated that although on the whole, single or multi‐site pain did not predict the onset of disability, multi‐site pain increased the risk of developing severe disability.

Conclusions

The findings of this study suggest that musculoskeletal pain in nonagenarians is highly prevalent and is associated with poor physical performance and disability.
Building on Content, Bridging Literacies, and Broadening Community
Authors: Skinner Emily Neil , Hagood Margaret Carmody
Published: August 2013

This editorial lays out the editors’ vision for Volume 57 of the Journal of Adolescent and Adult Literacy: to provide rich research, review a variety of print and digital texts for adolescents and adults and highlight diverse perspectives across departments regarding literacies learning and education. Also, the JAAL editors continue to cultivate active engagement of JAAL readers as both consumers and producers in the JAAL community through JAAL's Facebook page. Further, editors continue the inclusion of multimedia material through feature article video clips and podcasts.
Boundaries for Contemporary Literature: The Role of Censorship and Choice
Authors: Denzin Jen
Published: August 2013

Promoting student power in the choice of high school literature can prove uncomfortable, unruly, and contentious. Without enough preparation, research, and reading, teachers may find language, content, and themes to be more mature than initially anticipated. This essay explores one teacher's reflection of two instances when choice reading lead to discussions and written reflections of questionable content.

Providing a look into the potential pitfalls associated with choice reading for both the high school teacher and student, with insightful student responses and data from teacher‐research, the power that comes from choice ultimately trumps the fear of “inappropriate” content.
Giving Voice to Valeria's Story: Support, Value, and Agency for Immigrant Adolescents
Authors: Stewart Mary Amanda
Published: August 2013

The article presents the circumstances of a recent Salvadoran immigrant high school student who puts forth great effort to learn despite difficult circumstances caused by her immigration status, economic realities, and the educational system itself. The author issues a call to action for literacy educators to revolutionize their relationships with students, curriculum, and pedagogy. She discusses the need for teachers to give their immigrant students support through caring relationships, value of their lived experiences through relevant literature, and the agency they have lost through writing about their immigration stories.