bluuebunny/crossref_metadata_2025 huggingface dataset:
Plasma carotenoid levels are not directly related to heavy metal exposure or reproductive success in three insectivorous passerines
Authors: Eeva Tapio , Rainio Miia , Kanerva Mirella , Salminen Juha-Pekka
Published: April 2012

The authors measured plasma carotenoid levels in three insectivorous bird species, the pied flycatcher (Ficedula hypoleuca), the blue tit (Cyanistes caeruleus), and the great tit (Parus major) in metal-polluted and unpolluted sites around a copper smelter. Their aim was to determine whether there was interspecific, age-related, or yearly variation in carotenoid levels and their responses to the ambient pollution level. The three bird species showed qualitatively and quantitatively similar carotenoid profiles, with lutein being always the predominant plasma carotenoid. Ficedula hypoleuca nestlings showed higher plasma carotenoid levels in the unpolluted than in the polluted area, whereas no significant differences were found in F. hypoleuca females or in nestlings or females of the Parids. Yearly comparison of plasma concentrations (only for P. major nestlings) showed, however, that levels varied nonsynchronously between polluted and unpolluted sites among the breeding seasons, with the yearly variation being higher in the polluted area. The survival of nestlings did not depend on their plasma carotenoid concentrations. The two Parid species showed lower nestling survival at sites with high metal exposure levels. The authors conclude that plasma carotenoid levels showed a marked spatial, temporal, and age-related variation, but were not directly related to heavy metal exposure or the reproductive success of birds. Environ. Toxicol. Chem. 2012;31:1363–1369. © 2012 SETAC
Accumulation kinetics of arsenic in Daphnia magna under different phosphorus and food density regimes
Authors: Miao Ai-Jun , Wang Ning-Xin , Yang Liu-Yan , Wang Wen-Xiong
Published: April 2012

In the present study, the dissolved uptake, dietary assimilation, and elimination of arsenic (initially added as arsenate) in the freshwater cladoceran Daphnia magna were examined. A biphasic correlation between the arsenic uptake rate and its ambient concentration, as well as a two–saturation-site arsenic uptake competition with phosphate was observed. The calculated uptake rate constant, as influenced by the ambient phosphorus concentration, ranged from 0.035 to 0.35 L/g/d. Food concentration substantially decreased (by 23.2–64.4%) the arsenic assimilation efficiency with the incipient limiting algal food concentration of 3.86 mg/L dry weight. Arsenic assimilation by the daphnids was independent of their own phosphorus status, but was lower when their algal diet was phosphorus-limited and thus contained a higher proportion of arsenite due to the enhanced biotransformation. Arsenic efflux rate constant ranged from 0.34 to 0.44 d−1 with increased food concentration slightly facilitating its loss. Excretion, accounting for 51.3 to 60.6% of total loss, was the dominant pathway for arsenic elimination with a remarkable contribution from offspring production (24.7–29.8%), whereas molting (3.64–4.05%) and egestion (7.9–11.9%) had minor roles only. According to the well-established biokinetic model, dietary assimilation was predicted to be the main pathway for arsenic bioaccumulation in the daphnids, and arsenic has a great potential to be biodiminished along the food chain. Environ. Toxicol. Chem. 2012;31:1283–1291. © 2012 SETAC
Endocrine disruption due to estrogens derived from humans predicted to be low in the majority of U.S. surface waters
Authors: Anderson Paul D. , Johnson Andrew C. , Pfeiffer Danielle , Caldwell Daniel J. , Hannah Robert , Mastrocco Frank , Sumpter John P. , Williams Richard J.
Published: April 2012

In an effort to assess the combined risk estrone (E1), 17β-estradiol (E2), 17α-ethinyl estradiol (EE2), and estriol (E3) pose to aquatic wildlife across United States watersheds, two sets of predicted-no-effect concentrations (PNECs) for significant reproductive effects in fish were compared to predicted environmental concentrations (PECs). One set of PNECs was developed for evaluation of effects following long-term exposures. A second set was derived for short-term exposures. Both sets of PNECs are expressed as a 17β-estradiol equivalent (E2-eq), with 2 and 5 ng/L being considered the most likely levels above which fish reproduction may be harmed following long-term and short-term exposures, respectively. A geographic information system-based water quality model, Pharmaceutical Assessment and Transport Evaluation (PhATE™), was used to compare these PNECs to mean and low flow concentrations of the steroid estrogens across 12 U.S. watersheds. These watersheds represent approximately 19% of the surface area of the 48 North American states, contain 40 million people, and include over 44,000 kilometers of rivers. This analysis determined that only 0.8% of the segments (less than 1.1% of kilometers) of these watersheds would have a mean flow E2-eq concentration exceeding the long-term PNEC of 2.0 ng/L; only 0.5% of the segments (less than 0.8% of kilometers) would have a critical low flow E2-eq exceeding the short-term PNEC of 5 ng/L. Those few river segments where the PNECs were exceeded were effluent dominated, being either headwater streams with a publicly owned treatment works (POTW), or flowing through a highly urbanized environment with one or several POTWs. These results suggest that aquatic species in most U.S. surface waters are not at risk from steroid estrogens that may be present as a result of human releases. Environ. Toxicol. Chem. 2012;31:1407–1415. © 2012 SETAC
Establishment of a versatile seminoma model indicates cellular plasticity of germ cell tumor cells
Authors: Nettersheim Daniel , Westernströer Birgit , Haas Natalie , Leinhaas Anke , Brüstle Oliver , Schlatt Stefan , Schorle Hubert
Published: April 2012

In western countries, 60% of all malignancies diagnosed in men between 17–45 years of age are germ cell tumors (GCT). GCT arise from the common precursor lesion carcinoma in situ, which transforms within an average of 9 years into invasive Type‐II GCTs. Seminomas are considered to be the default developmental pathway of carcinoma in situ cells and the seminoma‐like cell line TCam‐2 has been used to study seminoma biology in vitro. However, the generation of an animal model, which would allow for the in vivo analysis of seminoma formation, remained elusive. We applied transplantation approaches using TCam‐2 cell transfer into ectopic (skin, brain) and orthopic (testis) sites of immunodeficient mice. We demonstrate that a transplantation into the seminiferous tubules results in formation of a carcinoma in situ/seminoma. In contrast, TCam‐2 cells adopt an embryonal carcinoma‐like fate when grafted to the flank or corpus striatum and display downregulation of the seminoma marker SOX17 and upregulation of the embryonal carcinoma markers SOX2 and CD30. Grafted TCam‐2 cells reduce AKT‐, ERK‐, EphA3‐, and Tie2/TEK‐signaling to levels comparable to embryonal carcinoma cells. Hence, TCam‐2 cell transplantation into the testis generated a carcinoma in situ/seminoma mouse model, which enables addressing the biology of these tumors in vivo. The fact that TCam‐2 cells give rise to a carcinoma in situ/seminoma or embryonal carcinoma in a transplantation site specific manner implies that conversion of carcinoma in situ/seminoma to an embryonal carcinoma does not require additional genetic aberrations but relies on signals from the tumor‐microenvironment. © 2012 Wiley Periodicals, Inc.
Osteopontin is a novel downstream target of SOX9 with diagnostic implications for progression of liver fibrosis in humans
Authors: Pritchett James , Harvey Emma , Athwal Varinder , Berry Andrew , Rowe Cliff , Oakley Fiona , Moles Anna , Mann Derek A. , Bobola Nicoletta , Sharrocks Andrew D. , Thomson Brian J. , Zaitoun Abed M. , Irving William L. , Guha Indra N. , Hanley Neil A. , Hanley Karen Piper
Published: April 2012

Osteopontin (OPN) is an important component of the extracellular matrix (ECM), which promotes liver fibrosis and has been described as a biomarker for its severity. Previously, we have demonstrated that Sex-determining region Y-box 9 (SOX9) is ectopically expressed during activation of hepatic stellate cells (HSC) when it is responsible for the production of type 1 collagen, which causes scar formation in liver fibrosis. Here, we demonstrate that SOX9 regulates OPN. During normal development and in the mature liver, SOX9 and OPN are coexpressed in the biliary duct. In rodent and human models of fibrosis, both proteins were increased and colocalized to fibrotic regions

in vivo

and in culture-activated HSCs. SOX9 bound a conserved upstream region of the

OPN

gene, and abrogation of

Sox9

in HSCs significantly decreased OPN production. Hedgehog (Hh) signaling has previously been shown to regulate

OPN

expression directly by glioblastoma (GLI) 1. Our data indicate that in models of liver fibrosis, Hh signaling more likely acts through SOX9 to modulate

OPN
. In contrast to Gli2 and Gli3, Gli1 is sparse in HSCs and is not increased upon activation. Furthermore, reduction of GLI2, but not GLI3, decreased the expression of both SOX9 and OPN, whereas overexpressing SOX9 or constitutively active GLI2 could rescue the antagonistic effects of cyclopamine on OPN expression.

Conclusion
: These data reinforce SOX9, downstream of Hh signaling, as a core factor mediating the expression of ECM components involved in liver fibrosis. Understanding the role and regulation of SOX9 during liver fibrosis will provide insight into its potential modulation as an antifibrotic therapy or as a means of identifying potential ECM targets, similar to OPN, as biomarkers of fibrosis.
Clinical significance of azathioprine metabolites for the maintenance of remission in autoimmune hepatitis
Authors: Dhaliwal Harpreet K. , Anderson Rory , Thornhill Elizabeth L. , Schneider Sarah , McFarlane Elaine , Gleeson Dermot , Lennard Lynne
Published: April 2012

Azathioprine (AZA) is used to maintain remission in autoimmune hepatitis (AIH), but up to 18% of patients are unresponsive. AZA is a prodrug, and the formation of active thioguanine nucleotide (TGN) metabolites varies widely. We aimed to assess the relationship between AZA metabolite concentrations (i.e., TGNs and methylmercaptopurine nucleotides [MeMPNs]), thiopurine methyltransferase (TPMT) activity, therapeutic response, and toxicity in adult patients with AIH prescribed a stable dose of AZA for the maintenance of remission. Red blood cell (RBC) TGNs and MeMPNs were measured in serial blood samples over a 2-year period. The average TGNs (avTGNs) and MeMPNs (avMeMPNs) concentrations for each patient were used for analysis. Therapeutic response was defined as the ability to maintain remission, defined as a normal serum alanine aminotransferase (ALT) level (ALT <33 IU/mL). Patients who maintained remission (n = 53), compared to those who did not (n = 17), tended to be on lower doses of AZA (1.7 versus 2.0 mg/kg/day;

P

= 0.08), but had significantly higher concentrations of avTGN (237 versus 177 pmol/8 × 108 RBCs;

P

= 0.025). There was no difference in MeMPN concentrations or TPMT activities between the two groups. There was a negative correlation between ALT and avTGN (rs = −0.32;

P

= 0.007). An avTGN concentration of >220 pmol/8 × 108 RBCs best predicted remission, with an odds ratio of 7.7 (

P

= 0.003). There was no association between TGN, MeMPN, or TPMT activity and the development of leucopenia. Two patients developed AZA-induced cholestasis and the avMeMPN concentration was higher in those patients, compared to those who did not (14,277 versus 1,416 pmol/8 × 108 RBCs).

Conclusion

: TGN concentrations of >220 pmol/8 × 108 RBCs are associated with remission. TGN measurement may help identify inadequate immunosupression. AZA-induced cholestasis was associated with increased MeMPN concentrations. (Hepatology 2012)
The effect of peatland harvesting on snow accumulation, ablation and snow surface energy balance
Authors: Ketcheson Scott J. , Whittington Peter N. , Price Jonathan S.
Published: April 2012

Snow distribution, ablation and snowmelt energy balance components were characterized in a vacuum harvested and an adjacent undisturbed forested section of a peatland during the 2009 snowmelt period to determine snow distribution and melt dynamics on a previously harvested peatland, since abandoned and partly revegetated. The forested peatland had the deepest snowpack at 121 cm, particularly along the edge of the forested section adjacent to the more windblown previously harvested peatland. The snowpack density was greatest in the harvested peatland, which was subject to greater wind compaction and mid‐winter melt‐refreeze episodes; however, snow water equivalence was higher in the forested peatland. Radiative fluxes dominated the snowmelt energy balance. Increased canopy cover within the forested peatland restricted incident radiation and delayed melt, whereas melt rates were rapid across the harvested peatland, driven by higher radiant and turbulent fluxes. Ablation calculated using a simple, one‐dimensional model showed good temporal agreement with the observed ablation trends except when standing melt water pooled on the surface of the harvested section, causing more rapid modelled melt rates than observed. The shallower snowpack and more rapid melt across the harvested peatland limited the amount of melt water that was available for spring recharge. Copyright © 2012 John Wiley & Sons, Ltd.
Prediction of overall survival through circadian rest‐activity monitoring during chemotherapy for metastatic colorectal cancer
Authors: Innominato Pasquale F. , Giacchetti Sylvie , Bjarnason Georg A. , Focan Christian , Garufi Carlo , Coudert Bruno , Iacobelli Stefano , Tampellini Marco , Durando Xavier , Mormont Marie‐Christine , Waterhouse Jim , Lévi Francis A.
Published: April 2012

The clinical relevance of circadian rhythm modifications in patients on chemotherapy is unknown. Even so, circadian parameter I<O before chemotherapy independently predicted overall survival. This study investigates the relevance of I<O measured during chemotherapy for survival and symptoms. The circadian rest‐activity pattern was monitored for 3 days using a wristwatch actigraph while 77 patients were receiving a chemotherapy course within an international randomized Phase III trial. Treatment consisted of first‐line chronomodulated or conventional delivery of 5‐fluorouracil, leucovorin and oxaliplatin for metastatic colorectal cancer. I<O was computed as the percentage of minutes of activity counts in bed which were below the median of activity out of bed. Circadian disruption was defined by I<O equal to or less than 97.5%. Circadian disruption occurred in 39 patients (51%) on chemotherapy. It was associated with a significantly shorter overall survival, independently of other prognostic factors (multivariate Hazard Ratio: 2.12; p = 0.004). The median survival of patients with a robust circadian rhythm was 22.3 months as compared to 14.7 months in those with circadian disruption during chemotherapy. No toxicity was significantly associated with circadian disruption, but the incidence of grade ≥2 fatigue and of body weight loss ≥5% was two and threefold higher, respectively, in patients with disrupted circadian rhythm on chemotherapy. Chemotherapy disrupted circadian activity rhythm in nearly 50% of the patients. Circadian disruption on chemotherapy predicted for shorter overall survival. The prevention of chemotherapy‐induced circadian disruption might reduce toxicity and improve efficacy in cancer patients.
N‐(4‐hydroxyphenyl)retinamide inhibits breast cancer cell invasion through suppressing NF‐KB activation and inhibiting matrix metalloproteinase‐9 expression
Authors: Kang Hyereen , Lee Minjae , Choi Kyung‐chul , Shin Dong‐Myoung , Ko Jesang , Jang Sung‐Wuk
Published: April 2012

Synthetic retinoid N‐(4‐hydroxyphenyl)retinamide (4‐HPR) has been reported to exhibit anti‐invasive and anti‐metastatic activities by suppressing the enzymatic activity of matrix metalloproteinase (MMP)‐9, but the underlying mechanism remains unclear. Here, we show that 4‐HPR blocks the activity of MMP‐9 in two ways: by reducing phorbol 12‐myristate 13‐acetate (PMA)‐induced MMP‐9 secretion and by suppressing cell invasion through the downregulation of MMP‐9 gene transcription in MCF‐7 breast cancer cells. 4‐HPR inhibits the transcriptional activity of MMP‐9 by reducing the DNA‐binding activity of NF‐κB on the MMP‐9 promoter as well as by inhibiting the degradation of IκBα, leading to cytoplasmic accumulation of NF‐κB. We also found that 4‐HPR inhibits invasion and MMP‐9 expression in the highly metastatic breast cancer cell line MDA‐MB‐231. Thus, 4‐HPR might be a potent anti‐invasive agent that works by suppressing MMP‐9 expression via the NF‐κB signaling pathway. J. Cell. Biochem. 113: 2845–2855, 2012. © 2012 Wiley Periodicals, Inc.
A novel technique to assess chromatin texture using pixel optical densitometry in oral squamous cell carcinoma
Authors: Natarajan Srikant , Juneja Manish , Pallam Nandita Kottieth , Boaz Karen , Mohindra Aashima , Lewis Amitha
Published: April 2012

Background: The early detection of neoplasia is the prime aim of a diagnostician. Altered chromatin distribution is the earliest microscopic change observed in malignant transformation making it a valuable morphometric parameter. This study was aimed to assess and correlate the progressive changes in chromatin texture from normal to varying grades of premalignancies to malignancy of the oral cavity. Methods: Thirty‐four archival tissue specimens categorized as normal buccal mucosa (5), low‐grade epithelial dysplasia (11), high‐grade epithelial dysplasia (7), and squamous cell carcinoma (11) were stained with Feulgen reaction. Pixel optical densitometry histograms were obtained from analysis of an average of 300 cells/case using ImageJ software. Nine histogram curve characteristics (including area under the curve, area integer percentage, center, centroid) were then analyzed statistically for differences between the four groups. Results: Area integer percentage (P = 0.002), center (P = 0.038), and centroid (P = 0.021) were statistically significant within the four groups The parameters showed a dip in their value from normal to low‐grade dysplasia but showed a steady increase in high‐grade dysplasia and carcinoma. Conclusion: The optical density characteristics had the ability to differentiate the progression of neoplastic changes by extracting information of the chromatin distribution not quantifiable by routine microscopy. The early clumping of chromatin in the periphery in low‐grade dysplasia followed by progressively increasing chromatin aggregates in high‐grade dysplasia and carcinoma correlated well with the shift observed in the histogram center and centroid. The novel pixel optical densitometry technique efficiently predicted malignant transformation. Microsc. Res. Tech. 75:1119–1123, 2012. © 2012 Wiley Periodicals, Inc.
MRI acoustic noise can harm experimental and companion animals
Authors: Lauer Amanda M. , El‐Sharkawy AbdEl‐Monem M. , Kraitchman Dara L. , Edelstein William A.
Published: April 2012

Purpose:

To assess possible damage to the hearing of experimental and companion animal subjects of magnetic resonance imaging (MRI) scans.

Materials and Methods:

Using animal hearing threshold data and sound level measurements from typical MRI pulse sequences, we estimated “equivalent loudness” experienced by several experimental and companion animals commonly subjects of MRI scans. We compared the equivalent loudness and exam duration to safe noise standards set by the National Institute for Occupational Safety and Health (NIOSH).

Results:

Monkeys, dogs, cats, pigs, and rabbits are frequently exposed to equivalent loudness levels during MRI scans beyond what is considered safe for human exposure. The sensitive frequency ranges for rats and mice are shifted substantially upward and their equivalent loudness levels fall within the NIOSH safe zone.

Conclusion:

MRI exposes many animals to levels of noise and duration that would exceed NIOSH human exposure limits. Researchers and veterinarians should use hearing protection for animals during MRI scans. Experimental research animals used in MRI studies are frequently kept and reimaged, and hearing loss could result in changed behavior. Damage to companion animals' hearing could make them less sensitive to commands and generally worsen interactions with family members. Much quieter MRI scanners would help decrease stress and potential harm to scanned animals, normalize physiology during MRI, and enable MRI of awake animals. J. Magn. Reson. Imaging 2012;36:743–747. © 2012 Wiley Periodicals, Inc.
Behavioral and histological analysis of a partial double‐lesion model of parkinson‐variant multiple system atrophy
Authors: Kaindlstorfer Christine , García Joanna , Winkler Christian , Wenning Gregor K. , Nikkhah Guido , Döbrössy Máté D.
Published: April 2012

Multiple system atrophy (MSA) is a neurodegenerative disease with progressive autonomic failure, cerebellar ataxia (MSA‐C), and parkinsonism (MSA‐P) resulting from neuronal loss in multiple brain areas associated with oligodendroglial cytoplasmic α‐synuclein inclusion bodies. No effective treatments exists, and MSA‐P patients often fail to respond to L‐DOPA because of the loss of striatal dopaminergic receptors. Rendering MSA‐P patients sensitive to L‐DOPA administration following striatal tissue transplantation has been proposed as a possible novel therapeutic strategy to improve the clinical condition. Here we describes simple, skilled, and sensorimotor behavior deficits in a unilateral partial double‐lesion (DL) rat model of MSA‐P. The sequential striatal double‐lesion model mimicks early MSA‐P pathology by combining partial 6‐hydroxydopamine (6‐OHDA) followed by striatal quinolinic acid (QA) lesion. Animals were tested on spontaneous, learned, or drug‐induced behavioral tasks on multiple occasions pre‐ and postsurgery. The data show robust, lateralized deficits, and the partial 6‐OHDA and the double‐lesioned animals were most impaired. Importantly, this study identified a behavioral deficit profile unique to the double‐lesion animals and distinctive from the single 6‐OHDA‐ or the QA‐lesioned animals. Histology confirmed an approximately 40% dopamine loss in the striatum in the 6‐OHDA and double‐lesion animals as well as a similar loss of striatal projection neurons in the QA and double‐lesion animals. In summary, we have established the behavioral deficit profile of a partial double‐lesion rat model mimicking the early stage of MSA‐P. © 2012 Wiley Periodicals, Inc.
Effect of cisplatin on distortion product otoacoustic emissions in Japanese patients
Authors: Eiamprapai Peem , Yamamoto Norio , Hiraumi Harukazu , Ogino‐Nishimura Eriko , Kitamura Morimasa , Hirano Shigeru , Ito Juichi
Published: April 2012

Objectives/Hypothesis:

Although it is well known that cisplatin is associated with ototoxicity, there is still a lack of knowledge concerning the ototoxicity of cisplatin, especially in Japanese head and neck cancer patients. The objectives of this study were to determine the incidence rate of cisplatin ototoxicity and to determine the threshold dose causing ototoxicity in the Japanese population.

Study Design:

Before‐and‐after study in a tertiary referral hospital.

Methods:

The distortion product otoacoustic emission (DPOAE) was measured 1 week after each administration of cisplatin in 44 Japanese head and neck cancer patients treated at Kyoto University Hospital. We determined the incidence and threshold dose of cisplatin ototoxicity according to DPOAE data.

Results:

The incidence of ototoxicity detected by DPOAE was 77.3%. The average DPOAE value was significantly lower in patients who received more than 200 mg/m2 cisplatin than the baseline DPOAE value. The threshold dose for cisplatin ototoxicity was lower in Japanese patients than in European patients.

Conclusions:

Our data suggest that Japanese patients are more susceptible to cisplatin‐induced ototoxicity. This is presumably caused by a genetic difference.
Revision cochlear implantation following internal auditory canal insertion
Authors: Heman‐Ackah Selena E. , Friedmann David R. , Cosetti Maura K. , Waltzman Susan B. , Roland J. Thomas
Published: April 2012

Objectives/Hypothesis

In pediatric patients with congenital malformations of the inner ear, anomalies within the anatomy may facilitate unintentional insertion of the cochlear implant electrode into the internal auditory canal. Revision procedures for removal and replacement of cochlear implant electrodes following internal auditory canal insertion are fraught with potential danger, including the theoretical risk of injury to vasculature within the internal auditory canal, repeat insertion within the internal auditory canal, and cerebrospinal fluid leak. The objective of this presentation is to describe a technique for revision cochlear implantation following internal auditory canal insertion to minimize the potential associated risks.

Study Design

Case series.

Methods

A retrospective chart review was performed on all patients at a tertiary care facility who underwent revision cochlear implantation for internal auditory canal insertion between January 1999 and July 2011.

Results

A total of four patients referred from outside institutions have undergone revision cochlear implantation for internal auditory canal insertion. The records from these patients were reviewed. Electrodes were safely removed in all cases without injury to the anterior inferior cerebellar artery or its branches (i.e., labyrinthine artery). Complete insertion was accomplished on reimplantation. Neural response telemetry was performed in all cases, and responses were noted. Fluoroscopy was utilized to visualize electrode progression during insertion. A detailed description of the operative technique is provided.

Conclusions

This case series describes a technique for revision cochlear implantation that appears to be safe and effective in preventing potential associated complications. Laryngoscope, 123:3141–3147, 2013
Chain‐Growth Polymerization of Aryl Grignards Initiated by a Stabilized NHC‐Pd Precatalyst
Authors: Bryan Zachary J. , Smith Mitchell L. , McNeil Anne J.
Published: April 2012

An N‐heterocyclic carbene‐ligated palladium catalyst was discovered to mediate living, chain‐growth polymerizations of both phenylene‐ and thiophene‐based monomers. Polymerization of a fluorene‐based monomer, on the other hand, did not proceed through a living, chain‐growth pathway. Excitingly, block copolymerizations of phenylene and thiophene proceeded via a chain‐growth pathway, regardless of the order of monomer addition. Although some chain termination was observed during these copolymerizations, this pathway could be minimized when the second monomer was added shortly after consumption of the first monomer. These results suggest that the catalyst resting‐state at the end of polymerization is unstable. As a result, modifications to the NHC‐scaffold or the 3‐chloropyridine ligand will be necessary to generate an improved catalyst.
Reduced field‐of‐view excitation using second‐order gradients and spatial‐spectral radiofrequency pulses
Authors: Ma Chao , Xu Dan , King Kevin F. , Liang Zhi‐Pei
Published: April 2012

The performance of multidimensional spatially selective radiofrequency (RF) pulses is often limited by their long duration. In this article, high‐order, nonlinear gradients are exploited to reduce multidimensional RF pulse length. Specifically, by leveraging the multidimensional spatial dependence of second‐order gradients, a two‐dimensional spatial‐spectral RF pulse is designed to achieve three‐dimensional spatial selectivity, i.e., to excite a circular region‐of‐interest in a thin slice for reduced field‐of‐view imaging. Compared to conventional methods that use three‐dimensional RF pulses and linear gradients, the proposed method requires only two‐dimensional RF pulses, and thus can significantly shorten the RF pulses and/or improve excitation accuracy. The proposed method has been validated through Bloch equation simulations and phantom experiments on a commercial 3.0T MRI scanner. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
Rapid measurement and correction of phase errors from B0 eddy currents: Impact on image quality for non‐cartesian imaging
Authors: Brodsky Ethan K. , Klaers Jessica L. , Samsonov Alexey A. , Kijowski Richard , Block Walter F.
Published: April 2012

Non‐Cartesian imaging sequences and navigational methods can be more sensitive to scanner imperfections that have little impact on conventional clinical sequences, an issue which has repeatedly complicated the commercialization of these techniques by frustrating transitions to multicenter evaluations. One such imperfection is phase errors caused by resonant frequency shifts from eddy currents induced in the cryostat by time‐varying gradients, a phenomenon known as B0 eddy currents. These phase errors can have a substantial impact on sequences that use ramp sampling, bipolar gradients, and readouts at varying azimuthal angles. We present a method for measuring and correcting phase errors from B0 eddy currents and examine the results on two different scanner models. This technique yields significant improvements in image quality for high‐resolution joint imaging on certain scanners. This result suggests that correcting short‐time B0 eddy currents that do not affect conventional clinical sequences may simplify the adoption of non‐Cartesian methods. Magn Reson Med, 2013. © 2012 Wiley Periodicals, Inc.
A quantitative measure of handgrip myotonia in non‐dystrophic myotonia
Authors: Statland Jeffrey M. , Bundy Brian N. , Wang Yunxia , Trivedi Jaya R. , Raja Rayan Dipa , Herbelin Laura , Donlan Merideth , McLin Rhonda , Eichinger Katy J. , Findlater Karen , Dewar Liz , Pandya Shree , Martens William B. , Venance Shannon L. , Matthews Emma , Amato Anthony A. , Hanna Michael G. , Griggs Robert C. , Barohn Richard J. ,   and the CINCH Consortium
Published: April 2012

Introduction: Non‐dystrophic myotonia (NDM) is characterized by myotonia without muscle wasting. A standardized quantitative myotonia assessment (QMA) is important for clinical trials. Methods: Myotonia was assessed in 91 individuals enrolled in a natural history study using a commercially available computerized handgrip myometer and automated software. Average peak force and 90% to 5% relaxation times were compared with historical normal controls studied with identical methods. Results: Thirty subjects had chloride channel mutations, 31 had sodium channel mutations, 6 had DM2 mutations, and 24 had no identified mutation. Chloride channel mutations were associated with prolonged first handgrip relaxation times and warm‐up on subsequent handgrips. Sodium channel mutations were associated with prolonged first handgrip relaxation times and paradoxical myotonia or warm‐up, depending on underlying mutations. DM2 subjects had normal relaxation times but decreased peak force. Sample size estimates are provided for clinical trial planning. Conclusion: QMA is an automated, non‐invasive technique for evaluating myotonia in NDM. Muscle Nerve 46: 482–489, 2012
Effect of nanoclay on positive temperature coefficient to resistivity characteristics of high density polyethylene/silver‐coated glass bead composites
Authors: Sridhar M.V. , Kar Prativa , Shrivastava N. , Khatua B.B.
Published: April 2012

Positive temperature coefficient to resistivity characteristics of high density polyethylene (HDPE)/silver (Ag)‐coated glass bead (45 wt%) composites, without and with nanoclay, has been investigated with reference to HDPE/carbon black (CB) (10 wt%) composites. Plot of resistivity versus temperature of HDPE/CB (10 wt%) composites showed a sudden rise in resistivity (PTC trip) at ≈128°C, close to the melting temperature (Tm) of HDPE. However, for HDPE/Ag coated glass bead (45 wt%) composites, the PTC trip temperature (≈88°C) appeared well below the Tm of HDPE. Addition of 1 phr clay in the composites resulted in an increase in PTC trip temperature of HDPE/Ag‐coated glass bead (45 wt%) composites, whereas no significant effect of clay on PTC trip temperature was evident in HDPE/CB/clay composites. We proposed that the PTC trip temperature in HDPE/Ag‐coated glass bead composites was governed by the difference in coefficient of thermal expansion of HDPE and Ag‐coated glass beads. The room temperature resistivity and PTC trip temperature of HDPE/Ag‐coated glass bead (45 wt%) composites were found to be very stable on thermal cycling. Dynamic mechanical analyzer results showed higher storage modulus of HDPE/Ag‐coated glass bead (45 wt%) composites compared with the HDPE/CB (10 wt%) composites. Thermal stability of HDPE/Ag‐coated glass bead (45 wt%) composites was also improved compared with that of HDPE/CB (10 wt%) composites. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Thermal and morphological properties of PVA/4‐vinylbenzene boronic acid hybrid nanofibrous
Authors: Baştürk Emre , Kahraman Memet Vezir
Published: April 2012

The aim of this study was to investigate the preparation and characterization of PVA and PVA/4‐VBBA (4‐Vinylbenzene boronic acid) hybrid electrospun nanofiber mat. PVA was mixed with cross‐linkable 4‐Vinylbenzene boronic acid (4‐VBBA), enabling the polymer to cross‐link upon UV irradiation. The photo‐cross‐linking reaction was characterized by a Fourier transform infrared spectroscopy. The structure and morphology of electrospun membranes were investigated by scanning electron microscopy (SEM). SEM images showed that the nanofiber diameter and the nanostructured morphology depended on solution viscosity, applied electric voltage(AV), tip to collector distance (TCD), and the amount of the 4‐VBBA. The thermal properties of PVA and PVA/4‐VBBA hybrid nanofibers were investigated by thermo gravimetric analysis. The photo‐crosslinked nanofibers were insoluble in water. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Loss ofmPer2increases plasma insulin levels by enhanced glucose‐stimulated insulin secretion and impaired insulin clearance in mice
Authors: Zhao Yue , Zhang Ying , Zhou Mengyi , Wang Shiming , Hua Zichun , Zhang Jianfa
Published: April 2012

The existence of peripheral oscillators has been shown, and they are critically important for organizing the metabolism of the whole body. Here we show that mice deficient inmPer2markedly increase circulatory levels of insulin compared with wild type mice. Insulin secretion was more effectively stimulated by glucose, and alloxan, a glucose analogue, induced more severe hyperglycemia inmPer2‐deficient mice. Hepatic insulin degrading enzyme (Ide) displayed an obvious day and night rhythm, which was impaired in mPer2‐deficient mice, leading to a decrease in insulin clearance. Deficiency inmPer2caused increasedClockexpression and decreased expression ofMkp1andIde1, possibly underlying the observed phenotypes and suggesting thatmPer2plays a role in regulation of circulating insulin levels.
James Watt
Authors: Dickinson H. W.
Published: April 2012

This 1936 book, published to celebrate the bicentenary of Watt's birth, examines his career as a craftsman and engineer, rather than offering a purely narrative biography. Watt began his life as a maker of mathematical instruments, and throughout his working life enjoyed the challenge of such skilled work. Watt's inventions did much to power the Industrial Revolution and its economic and social consequences. However, he owed much of his commercial success to his long partnership with Matthew Boulton, a far more astute businessman, and a considerable portion of the book is devoted to the achievements of this period. An engineer by profession, H. W. Dickinson researched widely, and published highly readable works on the steam engine, Watt, Boulton and Trevithick. He succeeds in producing a work which appeals to the scientist, the historian and the general reader, without feeling obliged to over-simplify the technical details.
The Algebra of Invariants
Authors: Grace John Hilton , Young Alfred
Published: April 2012

Invariant theory is a subject within abstract algebra that studies polynomial functions which do not change under transformations from a linear group. John Hilton Grace (1873–1958) was a research mathematician specialising in algebra and geometry. He was elected a Fellow of the Royal Society in 1908. His co-author Dr Alfred Young (1873–1940) was also a research mathematician before being ordained in 1908; in 1934 he too was elected a Fellow of the Royal Society. Abstract algebra was one of the new fields of study within mathematics which developed out of geometry during the nineteenth century. It became a major area of research in the late nineteenth and early twentieth centuries. First published in 1903, this book introduced the work on invariant theory of the German mathematicians Alfred Clebsch and Paul Gordan into British mathematics. It was considered the standard work on the subject.
Initia Amharica
Authors: Armbruster C. H.
Published: April 2012

C. H. Armbruster (1874–1957) was a civil servant in the Anglo-Sudan government and a linguist specialising in African languages. After visiting Ethiopia on diplomatic missions in 1906 and 1907 Armbruster published this three-volume reference work on colloquial, spoken Amharic between 1908 and 1920. Armbruster's study of Amharic was one of the first to be written in English, and exemplifies the shift among linguists away from the formal, classics-based style of earlier reference grammars towards a focus on colloquial speech and communication. The examples are drawn from direct knowledge of the contemporary language, unlike similar works of the period which were often based on centuries-old Ethiopian Orthodox biblical texts. Volume 2, published in 1910, is an English–Amharic vocabulary, with guidance on pronunciation and idiomatic Amharic translations of English phrases and sentences.
A Treatise on Plague
Authors: Simpson W. J.
Published: April 2012

The bubonic plague, in various forms, has been devastating human populations and affecting the very course of history for over 3000 years. This 1905 study by a renowned expert in the field represents the extent of early twentieth-century knowledge of a disease which was still killing millions at the time of first publication. Charting the history of the plague and its spread across the world, Simpson examines the causes of the disease, including the role of living conditions and poverty, as well as strategies for quarantine, prevention and treatment. Featuring autopsy reports, statistical data, photographs illustrating the symptoms and accounts of medical investigation of all aspects of the plague, this is a comprehensive and arresting overview of the disease. The book also features the full text of the 1903 International Sanitary Convention of Paris which was a response to the 1896 outbreak in India and China.
The Journal of George Fox
Authors: Fox George
Published: April 2012

George Fox, the founder of Quakerism, was born in 1642 at a time of great political turmoil when unorthodox religious ideas were met with intolerance and brutality. Rejecting his puritan background, Fox toured England, Europe and America, as a dissenting preacher. His unusual and uncompromising views led to frequent clashes with the church and the courts. Persecuted, beaten and frequently imprisoned for blasphemy, Fox was fearless in questioning the need for clergy and emphasising the accessibility of God to all. Compiled by John Nickalls from accounts dictated by Fox himself, this 1952 edition is an intimate depiction of the life and trials of a radical religious reformer who conquered depression, doubt and physical infirmity to advance the Quaker movement. It is an inspiring portrayal of the foundation and early struggles of the Religious Society of Friends and a personal account of the turbulent social and religious climate of the period.
Godofredi Hermanni Opuscula
Authors: Hermann Gottfried
Published: April 2012

Gottfried Hermann's Opuscula (1827–1877) collects in eight volumes the shorter writings of this central figure of nineteenth-century classical philology. Best known for his work on Greek metrics and his editions of Aeschylus, Euripides and others, Hermann (1772–1848) drew on Kantian phenomenology as well as his own formidable understanding of ancient grammars to advance a compelling program of classical scholarship that took language itself as the primary witness to the distant past. Hermann's grammar-based scholarship drew criticism, but established him as foundational to modern philology. As Sihler wrote in 1933, 'He accepted nothing on mere authority, but investigated the causes and roots of every matter.' Volume 1 (1827) contains essays on Greek literature, including a fragment from Sophocles' Clytemnestra, as well as occasional works, such as a poem dedicated to his university, Leipzig. This diverse collection provides fuller insight into the mind of this highly influential scholar.
Godofredi Hermanni Opuscula
Authors: Hermann Gottfried
Published: April 2012

Gottfried Hermann's Opuscula (1827–1877) collects in eight volumes the shorter writings of this central figure of nineteenth-century classical philology. Best known for his work on Greek metrics and his editions of Aeschylus, Euripides and others, Hermann (1772–1848) drew on Kantian phenomenology as well as his own formidable understanding of ancient grammars to advance a compelling program of classical scholarship that took language itself as the primary witness to the distant past. Hermann's grammar-based scholarship drew criticism, but established him as foundational to modern philology. As Sihler wrote in 1933, 'He accepted nothing on mere authority, but investigated the causes and roots of every matter.' Volume 2 (1827) contains essays on topics including Homer, Aeschylus' Glaucus Pontios, the Eumenides, and the Persians, and ancient Greek history and mythology. This diverse collection provides fuller insight into the mind of this highly influential scholar.
A Residence on the Shores of the Baltic
Authors: Rigby Elizabeth
Published: April 2012

When Elizabeth Rigby (1809–1893) embarked on her travels to the Baltic states in 1838, she was already a published author. She was to play a significant role as a writer and public figure throughout the nineteenth century. Originally published in 1841 as two separate volumes, this book is a compilation of letters written to her mother during her journey to Estonia. Travelling alone was an unusual undertaking for a single woman at the time, and here she demonstrates her ability to provide detailed descriptions of the life and places she experiences. The first volume describes her journey to Reval (Tallinn) in Estonia, where she will stay with her sister. The second offers her fascinating insights into the political and social life of Estonia in the mid-nineteenth century, combining personal observations and historical facts. For more information on this author, see http://orlando.cambridge.org/public/svPeople?person_id=rigbel
Travels in Northern Greece
Authors: Leake William Martin
Published: April 2012

William Martin Leake (1777–1860) was a British military officer and classical scholar specialising in reconstructing the topography of ancient cities. He was a founding member of the Royal Geographical Society and was elected a Fellow of the Royal Society in 1815. After his retirement in 1815, he devoted the rest of his life to topographical and classical studies. These volumes, first published in 1835, contain Leake's account of his four extensive journeys across Greece between 1804 and 1810. Using the form of a travelogue, Leake discusses the contemporary Greek and Turkish culture and provides detailed descriptions of ancient archaeological sites and geography. Leake's precise observations and detailed descriptions were influential in shaping the study of classical topography, with these volumes providing valuable information for the ancient sites and contemporary culture of the region. Volume 3 recounts his third and fourth journeys in Macedonia and Aetolia.
Reisen in Britisch-Guiana in den Jahren 1840–1844
Authors: Schomburgk Richard
Published: April 2012

Richard Schomburgk (1811–1891) accompanied his brother Robert Hermann Schomburgk on his mission to survey the boundary of British Guiana (his account is also reissued in this series). Richard was commissioned by the Prussian government to find new flora, fauna and ethnographical specimens for the Berlin Botanic Gardens and the royal museums. The publication in 1847–1848 in Germany of this three-volume account of the expedition was supported by Alexander von Humboldt, who was a close friend. Schomburgk contracted yellow fever, and found the preservation and transportation of his specimens difficult in the climate, many perishing before they got to Germany. Schomburgk later emigrated to Australia, becoming director of the Botanic Garden, Adelaide. This third volume, which concentrated on flora and fauna, was written with the assistance of some of the most renowned natural scientists of the day, and was considered a major taxonomical work.
Templar Families
Authors: Schenk Jochen
Published: April 2012

Founded in c.1120, in the aftermath of the First Crusade in Jerusalem, the Order of the Temple was a Christian brotherhood dedicated to the military protection of pilgrims and the Holy Land, attracting followers and supporters throughout Christian Europe. This detailed study explores the close relationship between the Order of the Temple and the landowning families it relied upon for support. Focussing on the regions of Burgundy, Champagne and Languedoc, Jochen Schenk investigates the religious expectations that guided noble and knightly families to found and support Templar communities in the European provinces, and examines the social dynamics and mechanisms that tied these families to each other. The book illustrates the close connection between the presence of Cistercians and the incidence of crusading within Templar family networks, and offers new insights into how collective identities and memory were shaped through ritual and tradition among medieval French-speaking social elites.
Theoria Motus Corporum Coelestium in Sectionibus Conicis Solem Ambientium
Authors: Gauss Carl Friedrich
Published: April 2012

Described by one reviewer as 'one of the most perfect books ever written on theoretical astronomy', this work in Latin by the German mathematician Carl Friedrich Gauss (1777–1855), the 'Prince of Mathematicians', derived from his attempt to solve an astronomical puzzle: where in the heavens would the dwarf planet Ceres, first sighted in 1801, reappear? Gauss' predicted position was correct to within half a degree, and this led him to develop a streamlined and sophisticated method of calculating the effect of the larger planets and the sun on the orbits of planetoids, which he published in 1809. As well as providing a tool for astronomers, Gauss' method also offered a way of reducing inaccuracy of calculations arising from measurement error; the primacy of this discovery was however disputed between him and the French mathematician Legendre, whose Essai sur la théorie des nombres is also reissued in this series.
Travels in Syria and the Holy Land
Authors: Burckhardt John Lewis
Published: April 2012

John Lewis Burckhardt (1784–1817) was a Swiss explorer who is best remembered for his rediscovery of the ancient city of Petra in modern Jordan. In 1809 he was commissioned by the African Association to discover the source of the River Niger. In preparation for this journey, for which he needed to pass as a Muslim, Burckhardt spent two years exploring and studying Arabic and Islamic law in Aleppo, before travelling widely in Arabia and Egypt. First published in 1822, this book provides 'a view of Arabian life and manners in every degree, from the Bedouin camp to the populous city', but the most striking passages describe the ruins of Petra, and especially its sumptuously carved Nabataean tombs. Burckhardt also records his frustration at not being able to explore freely and make notes, but these activities would have laid him open to suspicion of being a spy or an infidel, and almost certain death.