bluuebunny/crossref_metadata_2025 huggingface dataset:
Diazoxide Pretreatment Enhances L6 Skeletal Myoblast Survival and Inhibits Apoptosis Induced by Hydrogen Peroxide
Authors: Shao Su‐Xia , Zhang Lei , Chen Hong‐Xia , Liu Yan , Zhang Jin‐Ping , Chen Wei , Xue Guo‐Yu
Published: January 2012

Skeletal myoblast (SKM) transplantation is a promising approach to regenerate tissue and improve the function of the injured heart. However, the number of survival cells transplanted to host myocardium is quite poor due to high rate of apoptosis; diazoxide (DZ) is a highly selective mito‐KATP channel opener that may reduce cell apoptosis by relieving reactive oxygen species (ROS) damage. The aim of this study is to explore the protective effects of DZ on L6 SKM damage induced by hydrogen peroxide (H2O2) in vitro. Different dose and time of H2O2 and DZ treatment were performed and only 24 hr of 1.00 mmol/L H2O2 treatment and 200 μmol/L DZ pretreatment for 30 min were used for further experiment. L6 SKMs were cultured and divided into control group (no treatment), H2O2 group (24 hr of 1.00 mmol/L H2O2 treatment) and DZ + H2O2 group (pretreated with 200 μmol/L DZ for 30 min before 24 hr of 1.00 mmol/L H2O2 treatment). Compared with control group, H2O2 treatment caused cell damage, increased lactate dehydrogenase release, cell apoptosis, and bax gene expression, while reduced cell proliferation and decreased bcl‐2 expression. DZ pretreatment may protect cells from damage induced by H2O2 and reduce cell apoptosis by increasing bcl‐2 and decreasing bax expression. DZ pretreatment may also promote cell proliferation measured by both PCNA expression and flow cytometry method. These results suggest that DZ may protect L6 SKMs from damage induced by H2O2 by maintaining integrity of cell membrane, reducing apoptosis and increasing proliferation in vitro. Anat Rec, 2012. © 2012 Wiley Periodicals, Inc.
Segmentation of female pelvic cavity in axial T2‐weighted MR images towards the 3D reconstruction
Authors: Ma Zhen , Jorge Renato Natal M. , Mascarenhas T. , Tavares João Manuel R.S.
Published: January 2012

The anatomies of pelvic structures are critical for the diagnosis of pelvic floor dysfunctions. However, because of the complex background, the imaging appearances of pelvic organs and muscles are frequently distorted by noise and partial volume effect. Magnetic resonance imaging with its clear imaging quality of the female pelvic cavity is preferred for many studies. As such, correct segmentations of the pelvic structures on MR images are required for accurate diagnoses. Effective algorithms for axial T2‐weighted MR images have been proposed, which are based on the imaging features of different structures and various image clues. In this paper, we review these algorithms and evaluate their performance, and discuss implementation issues and aspects towards constructing the three‐dimensional models. Copyright © 2012 John Wiley & Sons, Ltd.
Laser Control of Zeolite Nucleation
Authors: Navarro Marta , Mayoral Álvaro , Mateo Ester , Lahoz Ruth , de la Fuente Germán F. , Coronas Joaquín
Published: January 2012

Precursor solutions for the synthesis of zeolites are irradiated by means of a Nd‐YAG laser. These solutions are subsequently submitted to a hydrothermal treatment and the results analyzed by X‐ray diffraction and electron microscopy. Laser irradiation promotes the formation of silica nanoparticles that nucleate into zeolite (silicalite‐1), following a hydrothermal treatment. The average crystal size (in the 0.6–3.6 μm range) of the zeolite exponentially decreases as a function of laser irradiation time. In addition, a longer irradiation time results in a narrower crystal size distribution.
FAK and PAX‐illin get involved in leukocyte diapedesis
Authors: Luscinskas Francis W.
Published: January 2012

A major focus of researchers studying leukocyte recruitment has been to identify and understand how cell surface endothelial adhesion molecules, cell‐to‐cell junctional protein complexes, secreted chemokines and chemoattractants, and the vessel basement membrane structure organization coordinate the process of leukocyte recruitment. As research expands beyond the components initially identified as being necessary for leukocyte recruitment, attention has turned to the structures that regulate endothelial cell‐to‐matrix adhesion. In this issue of the European Journal of Immunology, Parsons et al. [Eur. J. Immunol. 2012. 42: 436–446] identify new players in the regulation of neutrophil diapedesis (transendothelial migration), namely the focal adhesion proteins, paxillin and focal adhesion kinase (FAK). While understudied, and indeed previously underappreciated, in leukocyte diapedesis, this Commentary discusses how the work by Parsons et al. implicates FAK and paxillin in the proximal (leukocyte rolling) and distal (diapedesis) steps of the multistep adhesion cascade of leukocyte recruitment.
Recognition method for mid‐ to long‐term runoff forecasting factors based on global sensitivity analysis in the Nenjiang River Basin
Authors: Li Hongyan , Xie Miao , Jiang Shan
Published: January 2012

Mid‐ to long‐term runoff forecasting is important to China. Forecasting based on physical causes has become the trend of this field, and recognition of key factors is central to recent development. Here, global sensitivity analysis based on back‐propagation arithmetic was used to calculate the sensitivity of up to 24 factors that affect runoff in the Nenjiang River Basin. The following five indices were found to be key factors for mid‐ to long‐term runoff forecasting during flood season: Tibetan Plateau B, index of the strength of the East Asian trough, index of the area of the northern hemisphere polar vortex, zonal circulation index over the Eurasian continent and index of the strength of the subtropical high over the western Pacific. The hydrological climate of the study area and the rainfall–runoff laws were then analysed in conjunction with its geographical position and topographic condition. The rationality of the results can be demonstrated from the positive analysis point of view. The results of this study provide a general method for selection of mid‐ to long‐term runoff forecasting factors based on physical causes. Copyright © 2012 John Wiley & Sons, Ltd.
The COMT rs4680 Met allele contributes to long‐lasting low back pain, sciatica and disability after lumbar disc herniation
Authors: Jacobsen L.M. , Schistad E.I. , Storesund A. , Pedersen L.M. , Rygh L.J. , Røe C. , Gjerstad J.
Published: January 2012

Background

The COMT enzyme metabolizes catecholamines and thus modulates adrenergic, noradrenergic and dopaminergic signaling. A functional polymorphism in the gene encoding this enzyme, i.e. the COMT Val158Met SNP that reduces enzyme activity, has previously been linked to pain sensitivity.

Methods

We examined if the COMT Val158Met SNP could contribute to discogenic subacute low back pain and sciatica by comparing the frequency of the Val158Met genotypes of degenerative disc disease patients with healthy controls. Moreover, we examined if this SNP could predict the clinical outcome, i.e. the progression of pain and disability.

Results

The present data demonstrated that there were no differences in COMT genotype frequencies between the newly diagnosed patients and controls. Analysis of pain and disability in the patients over time revealed, however, a significant or border‐line significant increase in McGill sensory score and Oswestry Disability Index (ODI) score for individuals with COMT Met/Met genotype. Furthermore, significant associations between the COMT Met‐allele and VAS activity score, McGill sensory score and ODI score were observed in the patients 6 months after inclusion.

Discussion

Although the Val158Met SNP was not a risk factor for disc herniation, patients with Met/Met had more pain and slower recovery than those with Val/Met, which in turn also had more pain and slower recovery than those with Val/Val suggesting the SNP contributes to the progression of the symptoms of disc herniation.

Conclusion

We conclude that the functional COMT Val158Met SNP contributes to long lasting low back pain, sciatica and disability after lumbar disc herniation.
THE EFFECT OF PARENTAL EMPLOYMENT ON CHILD SCHOOLING
Authors: Ermisch John , Francesconi Marco
Published: January 2012

This paper presents a model that provides conditions under which a causal interpretation can be given to the association between childhood parental employment and subsequent educational attainments of children. The key parameter comes from theconditional demand function for children's future earning capacity. Its identification rests on having data on siblings and assumptions about the timing of parents' knowledge of their children's endowments. In addition to sibling differences, the useof a fixed‐effects instrumental‐variables estimator identifies the parameter under weaker conditions. Empirical analysis informed by the model reveals a negative and significant effect on the child's educational attainment of the months of the mother's full‐time employment when the child was aged 0–5. The effect of the mother's part‐time employment is smaller and less well determined, but again negative. These results suggest that the substitution effect of the mother's employment dominates the income effects. Stronger adverse effects are found for children of less‐educated mothers. Copyright © 2012 John Wiley & Sons, Ltd.
Different signal intensity at Gd‐EOB‐DTPA compared with Gd‐DTPA‐enhanced MRI in hepatocellular carcinoma transgenic mouse model in delayed phase hepatobiliary imaging
Authors: Korkusuz Huedayi , Knau Lea L. , Kromen Wolfgang , Bihrer Verena , Keese Daniel , Piiper Albrecht , Vogl Thomas J.
Published: January 2012

Purpose:

To evaluate hyperintense Gd‐DTPA‐ compared with hyper‐ and hypointense Gd‐EOB‐DTPA‐enhanced magnet resonance imaging (MRI) in c‐myc/TGFα transgenic mice for detecting hepatocellular carcinoma (HCC).

Materials And Methods:

Twenty HCC‐bearing transgenic mice with overexpression of the protooncogene c‐myc and transforming growth factor‐alpha (TGF‐α) were analyzed. MRI was performed using a 3‐T MRI scanner and an MRI coil. The imaging protocol included Gd‐DTPA‐ and Gd‐EOB‐DTPA‐enhanced T1‐weighted images. The statistically evaluated parameters are signal intensity (SI), signal intensity ratio (SIR), contrast‐to‐noise ratio (CNR), percentage enhancement (PE), and signal‐to‐noise ratio (SNR).

Results:

On Gd‐DTPA‐enhanced MRI compared with Gd‐EOB‐DTPA‐enhanced MRI, the SI of liver was 265.02 to 573.02 and of HCC 350.84 to either hyperintense with 757.1 or hypointense with 372.55 enhancement. Evaluated parameters were SNR of HCC 50.1 to 56.5/111.5 and SNR of liver parenchyma 37.8 to 85.8, SIR 1.32 to 1.31/0.64, CNR 12.2 to 26.1/−30.08 and PE 42.08% to 80.5/−98.2%, (P < 0.05).

Conclusion:

Gd‐EOB‐DTPA is superior to Gd‐DTPA for detecting HCC in contrast agent‐enhanced MRI in the c‐myc/TGFα transgenic mouse model and there was no difference between the hyperintense or hypointense appearance of HCC. Either way, HCCs can easily be distinguished from liver parenchyma in mice. J. Magn. Reson. Imaging 2012;35:1397–1402. © 2012 Wiley Periodicals, Inc.
Facile Synthesis of Supramolecular Ionic Polymers That Combine Unique Rheological, Ionic Conductivity, and Self‐Healing Properties
Authors: Aboudzadeh M. Ali , Muñoz M. Eugenia , Santamaría Antxon , Marcilla Rebeca , Mecerreyes David
Published: January 2012

A new family of supramolecular ionic polymers is synthesized by a simple method using (di‐/tri‐)carboxylic acids and (di‐/tri‐)alkyl amines. These polymers are formed by carboxylate and ammonium molecules that are weakly bonded together by a combination of ionic and hydrogen bonds, becoming solid at room temperature. The supramolecular ionic polymers show a sharp rheological transition from a viscoelastic gel to a viscous liquid between 30 and 80 °C. This sharp viscosity decrease is responsible for an unprecedented jump in ionic conductivity of four orders of magnitude in that temperature range. As a potential application, this chemistry can be used to develop polymeric materials with self‐healing properties, since it combines properties from supramolecular polymers and ionomers into the same material.
From Molecular Docking to 3D‐Quantitative Structure‐Activity Relationships (3D‐QSAR): Insights into the Binding Mode of 5‐Lipoxygenase Inhibitors
Authors: Eren Gokcen , Macchiarulo Antonio , Banoglu Erden
Published: January 2012

Pharmacological intervention with 5‐Lipoxygenase (5‐LO) is a promising strategy for treatment of inflammatory and allergic ailments, including asthma. With the aim of developing predictive models of 5‐LO affinity and gaining insights into the molecular basis of ligand‐target interaction, we herein describe QSAR studies of 59 diverse nonredox‐competitive 5‐LO inhibitors based on the use of molecular shape descriptors and docking experiments. These studies have successfully yielded a predictive model able to explain much of the variance in the activity of the training set compounds while predicting satisfactorily the 5‐LO inhibitory activity of an external test set of compounds. The inspection of the selected variables in the QSAR equation unveils the importance of specific interactions which are observed from docking experiments. Collectively, these results may be used to design novel potent and selective nonredox 5‐LO inhibitors.
Low‐frequency nonlinear memory effects in M‐ary QAM communications systems
Authors: Allegue‐Martínez Michel , Madero‐Ayora María J. , Reina‐Tosina Javier , Navarro‐Lázaro J. , Crespo‐Cadenas Carlos
Published: January 2012

This article focuses on low‐frequency nonlinear memory effects caused by a power amplifier (PA). Two models have been adopted for the PA to perform simulations of an M‐ary communications system, the memory polynomial model and a dynamic Volterra‐based model, both were able to predict the desired effects. An experimental setup allowing the identification of the coefficients using time‐domain data acquisitions has been used, with the capability to represent the distorted signal in the constellation plane and to make error vector magnitude measurements. A good agreement between simulations with the adopted models and measurements has been obtained, showing the degradation of the communications system due to low‐frequency nonlinear memory effects. A significant distortion and Eb/No losses are observed when a symbol rate of 17 ksym/s (low frequency zone) is used, when compared with the behavior of the system at 2 Msym/s. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:826–829, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26608
Compact dual‐band MIMO antenna for 4G USB dongle applications
Authors: Li Zuxing , Han Minseok , Choi Jaehoon
Published: January 2012

An extremely compact dual‐band MIMO antenna for 4G USB dongle applications is proposed for operation in the long term evolution (LTE) band 13 (0.746–0.787 GHz) and the M‐WiMAX band (2.5–2.69 GHz).The proposed multiple‐input multiple‐output (MIMO) antenna consists of two identical elements, each of which is 15 × 13.25 mm2. The minimum separation between the two elements is 0.5 mm (about 0.13% of the wavelength in free space at 0.765 GHz). Each antenna element of the proposed MIMO system is composed of a feeding strip, a spiral‐like radiating strip, and an L‐shaped parasitic strip. The radiating and L‐shaped strips are short‐circuited to the ground plane. The radiating and parasitic strips, which are capacitively coupled to the feeding strip, operate not only as radiators but also work as resonators to reduce the coupling between the two closely packed input ports. The proposed MIMO antenna has a measured port‐to‐port isolation performance of more than 13 dB over the frequency bands of interest. In addition, the ECCs are maintained below 0.3. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:744–748, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26612
Concurrent dual band class F power amplifier with novel harmonic control network
Authors: Ding Yao , Guo Yong‐Xin , Liu Fa‐Lin , You Lan
Published: January 2012

In this article, we present a novel two‐section transmission line (TSTL) based dual band harmonic control (HC) technique applied to the design of high efficiency power amplifier (PA).The dual band TSTL design criterion is investigated for three particular cases and a class‐F HC network adopting all the three kinds of TSTLs is designed. For further demonstration, we realized and fabricated a harmonic tuned PA operating concurrently at 0.8 and 1.9 GHz. Experimental results have shown 75% and 72% PAE at 40.1 and 43.3 dBm output power in the two targeted bands. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:707–711, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26629
Design of an indoor repeater antenna with high isolation using metamaterials
Authors: Lee Youngki , Ha Jeageun , Choi Jaehoon
Published: January 2012

In this article, an innovative indoor repeater antenna with high isolation is proposed. The necessary impedance bandwidth is obtained using the coupling between the main and parasitic patches. A high isolation between transmitting and receiving antennas is achieved using metamaterial. The fabricated indoor repeater antenna has a VSWR less than 1.5, a gain higher than 9.6 dBi, and an isolation between the transmitting and receiving antennas greater than 80 dB over the WiBro band from 2.3 to 2.5 GHz. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:755–761, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26651
Planar dual‐band dipole array for long‐term evolution/worldwide interoperability for microwave access points
Authors: Lu Jui‐Han , Liu Yen‐Hung
Published: January 2012

This article proposes a novel planar dipole array antenna with dual‐band operation for long‐term evolution (LTE)/worldwide interoperability for microwave access (WiMAX) communication systems. This array antenna is comprised of four dipole antennas to obtain high gain with the array antenna size of only 32 × 246 mm2. The impedance bandwidths, determined from VSWR ≤ 2.0, can reach about 555/765 MHz (21.3/21.9%) for the 2.6/3.5 GHz operating bands, respectively, which is covering the required bandwidth for LTE (2.5–2.7 GHz) and WiMAX (3.3–3.7 GHz) system. This proposed dual‐band dipole array also provides maximum peak antenna gains and efficiencies of 6.9/6.5 dBi and 85/79% across 2.6/3.5 GHz bands, respectively, with good omnidirectional radiation pattern in XY‐plane. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:811–815, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26660
New UWB antenna design for wireless communications
Authors: Bithikh M. , Aksas R. , Kimouche H. , Azrar A.
Published: January 2012

The presented work in this article concerns a new ultra‐wideband antenna design with an octagonal configuration and reduced dimensions. Different prototypes have been simulated and implemented in the form of monopoles. These prototypes have shown an admissible agreement between simulations and measurements and ultra‐wide bands running from 3.1 to 14 GHz for wireless applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:692–697, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26666
Efficient Stage-Specific Differentiation of Human Pluripotent Stem Cells Toward Retinal Photoreceptor Cells
Authors: Mellough Carla B. , Sernagor Evelyne , Moreno-Gimeno Inmaculada , Steel David H.W. , Lako Majlinda
Published: January 2012

Recent successes in the stem cell field have identified some of the key chemical and biological cues which drive photoreceptor derivation from human embryonic stem cells (hESC) and human induced pluripotent stem cells (hiPSC); however, the efficiency of this process is variable. We have designed a three-step photoreceptor differentiation protocol combining previously published methods that direct the differentiation of hESC and hiPSC toward a retinal lineage, which we further modified with additional supplements selected on the basis of reports from the eye field and retinal development. We report that hESC and hiPSC differentiating under our regimen over a 60 day period sequentially acquire markers associated with neural, retinal field, retinal pigmented epithelium and photoreceptor cells, including mature photoreceptor markers OPN1SW and RHODOPSIN with a higher efficiency than previously reported. In addition, we report the ability of hESC and hiPSC cultures to generate neural and retinal phenotypes under minimal culture conditions, which may be linked to their ability to endogenously upregulate the expression of a range of factors important for retinal cell type specification. However, cultures that were differentiated with full supplementation under our photoreceptor-induction regimen achieve this within a significantly shorter time frame and show a substantial increase in the expression of photoreceptor-specific markers in comparison to cultures differentiated under minimal conditions. Interestingly, cultures supplemented only with B27 and/or N2 displayed comparable differentiation efficiency to those under full supplementation, indicating a key role for B27 and N2 during the differentiation process. Furthermore, our data highlight an important role for Dkk1 and Noggin in enhancing the differentiation of hESC and hiPSC toward retinal progenitor cells and photoreceptor precursors during the early stages of differentiation, while suggesting that further maturation of these cells into photoreceptors may not require additional factors and can ensue under minimal culture conditions.

Disclosure of potential conflicts of interest is found at the end of this article.
An Oxalate‐Bridged Copper(II) Dimer and a Mononuclear ­Cobalt(III) Azide Complex Containing N‐Nitrile‐Functionalized 1, 4, 7‐Triazacyclononane Terminals: Synthesis, Crystal Structure, and Magnetic Characterization
Authors: Zhang Zhong , Shao Da‐Lin , Geng Zhi‐Rong , Wang Zhi‐Lin
Published: January 2012

The stable dinuclear [Cu(μ‐C2O4)Cu]2+ entity is facially coordinated at each end by a N‐nitrile functionalized triazamacrocycle, 1, 4, 7‐tris(cyanomethyl)‐1, 4, 7‐triazacyclononane (L), to generate a centrosymmetric compound [Cu2L2(μ‐C2O4)](ClO4)2·4DMF (1) containing a bis‐bidentate oxalate bridge. The variable‐temperature magnetic measurement for the crystallographically characterized compound exhibits quite strong antiferromagnetic coupling interaction between two oxalate‐linked CuII atoms separated by 5.149 Å with a singlet‐triplet energy gap of –345.5 cm–1. On the other hand, a mononuclear CoIII compound [CoL(N3)3]·2.5H2O (2) with monodentate azide terminal groups was synthesized. Structural elucidation by X‐ray diffraction shows that the compound has crystallographically imposed C3 symmetry. Enantiomerically pure crystals were obtained upon crystallization indicated by a Flack parameter of 0.04(5).
Racial and Ethnic Differences in Direct‐to‐Consumer Genetic Tests Awareness in HINTS 2007: Sociodemographic and Numeracy Correlates
Authors: Langford Aisha T. , Resnicow Ken , Roberts J. Scott , Zikmund‐Fisher Brian J.
Published: January 2012

To examine the association of 1) race/ethnicity and 2) numeracy with awareness of DTC genetic tests. Secondary analysis of 6,754 Hispanic, black, and white adult respondents to the National Cancer Institute's 2007 Health Information National Trends Survey (HINTS). Logistic regression was used to examine sociodemographic predictors of DTC genetic tests awareness including race/ethnicity, income, education, and gender. Next, two numeracy variables were added to the model. After controlling for sociodemographic variables, black respondents were significantly less likely to have heard of DTC genetic tests compared to white respondents (OR = 0.79; CI: 0.65–0.97). When numeracy variables were added to the model, the effect of black race was no longer significant (OR = 0.84; CI: 0.69–1.04). Hispanic respondents did not significantly differ from white respondents in awareness of DTC genetic tests. Other significant correlates of DTC genetic tests awareness in the full model included education, income, age, and numeracy variables including degree to which people use medical statistics and numbers to make health decisions, and preference for words or numbers when discussing “the chance of something happening.” Although black respondents were generally less aware of DTC genetic tests than white respondents, this relationship appears to be partially mediated by numeracy.
A review of spatial and temporal variation in grey and common seal diet in the United Kingdom and Ireland
Authors: Brown Susie L. , Bearhop Stuart , Harrod Chris , McDonald Robbie A.
Published: January 2012

Knowledge about the diet of fish-eating predators is critical when evaluating conflicts with the fishing industry. Numerous primary studies have examined the diet of grey sealsHalichoerus grypusand common sealsPhoca vitulinain a bid to understand the ecology of these predators. However, studies of large-scale spatial and temporal variation in seal diet are limited. Therefore this review combines the results of seal diet studies published between 1980 and 2000 to examine how seal diet varies at a range of spatial and temporal scales. Our results revealed extensive spatial variation in gadiform, perciform and flatfish consumption, likely reflecting variation in prey availability. Flatfish and gadiform consumption varied between years, reflecting changes in fish assemblages as a consequence of factors such as varying fishing pressures, climate change and natural fluctuations in populations. Perciform and gadiform consumption varied seasonally: in addition there was a significant interaction between season and seal species, indicating that grey and common seals exhibited different patterns of seasonal variation in their consumption of Perciformes and Gadiformes. Multivariate analysis of grey seal diet revealed spatial variation at a much smaller scale, with different species dominating the diet in different areas. The existence of spatial and temporal variation in seal diet emphasizes that future assessments of the impact of seal populations should not be based on past or localized estimates of diet and highlights the need for up-to-date, site specific estimates of diet composition in the context of understanding and resolving seal/fisheries conflict.
Phylogenetic analyses and redescription of Tegula ignota (Mollusca: Vetigastropoda)
Authors: Collado Gonzalo A. , Méndez Marco A. , Brown Donald I. , Pérez-Schultheiss Jorge
Published: January 2012

The original description of Tegula ignota was based on three shells found on the coast of Totoralillo Sur, northern Chile. Until now, there are no reports of living specimens of the species. The present study redescribes this snail based on shell, radula, epipodium and mantle characteristics observed in living specimens collected from the subtidal zone of La Boca, central Chile. Additionally, we extend the distribution of T. ignota more than 700 km to the south-eastern Pacific with additional material. Molecular analyses based on the 16S ribosomal DNA mitochondrial gene show that T. ignota is most closely related to Tegula atra than other Chilean species of Tegula. Voucher specimens of T. ignota were deposited in the Museo Nacional de Historia Natural de Chile.
Could Captain Scott have been saved? Revisiting Scott's last expedition
Authors: May Karen
Published: January 2012

Captain Scott has been criticised for indecisiveness and for not making use of the dog teams for his own relief in his Terra Nova Expedition (1910–1913). This essay will demonstrate how a mistake made in Roland Huntford's double biography of Scott and Amundsen in 1979, repeated in polar writing by various authors until the present day, has maligned Scott's reputation. In fact, Scott left appropriate written orders in October 1911 for the polar party's relief by the dog teams, orders that were not subsequently implemented by the men at base. A re-examination of the actions and roles of two expedition members in particular, Lieutenant E.R.G.R. Evans and Surgeon Edward Atkinson, suggests strongly that misjudgements back at Cape Evans led to the failure of the mission to rescue Scott and his polar party. In this account all distances are in geographical miles.
Changes in seasonal land precipitation during the latter twentieth‐century
Authors: Noake K. , Polson D. , Hegerl G. , Zhang X.
Published: January 2012

Climate models predict substantial changes in seasonal precipitation in the future. Anthropogenic forcing has been found to contribute to the observed pattern of land precipitation change over the 2nd half of the 20th century when annual precipitation is averaged within latitude bands, the observed change was substantially larger than response simulated in climate models, based on a single observational dataset. Here we investigate the robustness of this finding using several land only observational datasets and look for an explanation for why observed changes are significantly larger. We show the discrepancy between model simulated and observed trends is reduced when changes are expressed as percent climatology, which reduces the difference in scale between observed point locations and model gridboxes. Focusing on seasonal rather than annual data reveals that there are seasonal differences in the pattern of zonal precipitation changes over the 20th century. We use fingerprint for zonal precipitation changes from 54 CMIP3 simulations and show that observed changes are detectable in all seasons but boreal summer (JJA), even when doubling the variance of the model simulation, and irrespective of the dataset used. The observed change is still larger than that simulated by the multi‐model mean in all datasets except in boreal summer but only in boreal spring is the observed change robustly and significantly larger than that simulated.
Large‐scale mapping of human protein interactome using structural complexes
Authors: Tyagi Manoj , Hashimoto Kosuke , Shoemaker Benjamin A , Wuchty Stefan , Panchenko Anna R
Published: January 2012

Although the identification of protein interactions by high‐throughput (HTP) methods progresses at a fast pace, ‘interactome’ data sets still suffer from high rates of false positives and low coverage. To map the human protein interactome, we describe a new framework that uses experimental evidence on structural complexes, the atomic details of binding interfaces and evolutionary conservation. The structurally inferred interaction network is highly modular and more functionally coherent compared with experimental interaction networks derived from multiple literature citations. Moreover, structurally inferred and high‐confidence HTP networks complement each other well, allowing us to construct a merged network to generate testable hypotheses and provide valuable experimental leads.
Mammalian Metabolism of Insecticides
Authors: Chambers Janice E , Meek Edward C
Published: January 2012

An overview of the major phase 1 and phase 2 reactions involved in the metabolism of insecticides in mammals is provided. The metabolism of some important selected insecticides within each of the major historic and current use classes of insecticides is described: organochlorine insecticides (including the chlorinated diphenylethanes and the chlorinated cyclodienes), organophosphorus insecticides, N-methylcarbamate insecticides, pyrethroid insecticides and neonicotinoid insecticides. The impacts of metabolism on the acute toxicity levels of the insecticides as well as the likelihood of the insecticides or their metabolites to bioaccumulate are also discussed.
Toxicity of Organophosphates and Carbamates
Authors: Gupta Ramesh C , Milatovic Dejan
Published: January 2012

Organophosphate (OP) and carbamate (CM) compounds are commonly used as insecticides around the world. Some of them are extremely toxic to non-target species, including mammals. OP and CM insecticides are acetylcholinesterase (AChE) inhibitors and are commonly referred to as anticholinesterase agents. In addition to their cholinergic mechanisms, these insecticides exert toxicity through non-cholinergic mechanisms, thereby affecting several vital organs and body systems. The brain and skeletal muscles are the major target organs. Cardiovascular, respiratory and immune systems are also affected. There are similarities and differences between and among the toxicity profiles of OPs and CMs. This is due in part to variability in the interaction of each OP or CM with target and non-target receptors, enzymes and proteins. Treatment of CM poisoning rests with atropine, while the treatment of OP poisoning includes atropine in combination with an oxime.
Intermediate conductance calcium-activated potassium channels modulate summation of parallel fiber input in cerebellar Purkinje cells
Authors: Engbers Jordan D. T. , Anderson Dustin , Asmara Hadhimulya , Rehak Renata , Mehaffey W. Hamish , Hameed Shahid , McKay Bruce E. , Kruskic Mirna , Zamponi Gerald W. , Turner Ray W.
Published: January 2012

Encoding sensory input requires the expression of postsynaptic ion channels to transform key features of afferent input to an appropriate pattern of spike output. Although Ca
2+
-activated K
+
channels are known to control spike frequency in central neurons, Ca
2+
-activated K
+
channels of intermediate conductance (KCa3.1) are believed to be restricted to peripheral neurons. We now report that cerebellar Purkinje cells express KCa3.1 channels, as evidenced through single-cell RT-PCR, immunocytochemistry, pharmacology, and single-channel recordings. Furthermore, KCa3.1 channels coimmunoprecipitate and interact with low voltage-activated Cav3.2 Ca
2+
channels at the nanodomain level to support a previously undescribed transient voltage- and Ca
2+
-dependent current. As a result, subthreshold parallel fiber excitatory postsynaptic potentials (EPSPs) activate Cav3 Ca
2+
influx to trigger a KCa3.1-mediated regulation of the EPSP and subsequent after-hyperpolarization. The Cav3-KCa3.1 complex provides powerful control over temporal summation of EPSPs, effectively suppressing low frequencies of parallel fiber input. KCa3.1 channels thus contribute to a high-pass filter that allows Purkinje cells to respond preferentially to high-frequency parallel fiber bursts characteristic of sensory input.
Magnetic phase diagram of non-magnetic few-electron quantum dot molecules
Authors: Ribeiro-Santos D , Qu Fanyao , Lopez-Richard V , Marques G E
Published: January 2012

A pathway to design non-magnetic artificial molecules which display controllable magnetic properties is addressed theoretically by studying the effects of in-plane electrical field, spin–orbit interaction (SOI) and geometrical parameters on the magnetic phase transitions in few-electron lateral double quantum dots (DQDs). We demonstrate the tunability of the magnetic phase diagram of two-electron DQDs as the system is changed from a molecule to an atom, in both weak and strong SOI regimes. We find an unusual jump in the magnetization and an asymmetric peak of the magnetic susceptibility. In addition, both the asymmetric susceptibility peak position and the magnetic phase diagram are strongly dependent on the interdot tunnel coupling, which can be tuned effectively by changing repulsive barrier voltage and/or interdot distance, the number of electrons and the SOI strength. With increasing interdot tunnel-coupling strength, for instance, the rate of paramagnetic-to-diamagnetic phase area increases. The SOI makes the paramagnetic phase more stable under magnetic field. Moreover, the effects of geometry deviation on the electronic structure and magnetic property of the DQD are also discussed.
The distribution of phosphorylated SR proteins and alternative splicing are regulated by RANBP2
Authors: Saitoh Noriko , Sakamoto Chiyomi , Hagiwara Masatoshi , Agredano-Moreno Lourdes T. , Jiménez-García Luis Felipe , Nakao Mitsuyoshi
Published: January 2012

The mammalian cell nucleus is functionally compartmentalized into various substructures. Nuclear speckles, also known as interchromatin granule clusters, are enriched with SR splicing factors and are implicated in gene expression. Here we report that nuclear speckle formation is developmentally regulated; in certain cases phosphorylated SR proteins are absent from the nucleus and are instead localized at granular structures in the cytoplasm. To investigate how the nuclear architecture is formed, we performed a phenotypic screen of HeLa cells treated with a series of small interfering RNAs. Depletion of Ran-binding protein 2 induced cytoplasmic intermediates of nuclear speckles in G1 phase. Detailed analyses of these structures suggested that a late step in the sequential nuclear entry of mitotic interchromatin granule components was disrupted and that phosphorylated SR proteins were sequestered in an SR protein kinase–dependent manner. As a result, the cells had an imbalanced subcellular distribution of phosphorylated and hypophosphorylated SR proteins, which affected alternative splicing patterns. This study demonstrates that the speckled distribution of phosphorylated pre-mRNA processing factors is regulated by the nucleocytoplasmic transport system in mammalian cells and that it is important for alternative splicing.
Chk1 and Wee1 kinases coordinate DNA replication, chromosome condensation, and anaphase entry
Authors: Fasulo Barbara , Koyama Carol , Yu Kristina R. , Homola Ellen M. , Hsieh Tao S. , Campbell Shelagh D. , Sullivan William
Published: January 2012

Defects in DNA replication and chromosome condensation are common phenotypes in cancer cells. A link between replication and condensation has been established, but little is known about the role of checkpoints in monitoring chromosome condensation. We investigate this function by live analysis, using the rapid division cycles in the early Drosophila embryo. We find that S-phase and topoisomerase inhibitors delay both the initiation and the rate of chromosome condensation. These cell cycle delays are mediated by the cell cycle kinases chk1 and wee1. Inhibitors that cause severe defects in chromosome condensation and congression on the metaphase plate result in delayed anaphase entry. These delays are mediated by wee1 and are not the result of spindle assembly checkpoint activation. In addition, we provide the first detailed live analysis of the direct effect of widely used anticancer agents (aclarubicin, ICRF-193, VM26, doxorubicin, camptothecin, aphidicolin, hydroxyurea, cisplatin, mechlorethamine and x-rays) on key nuclear and cytoplasmic cell cycle events.
1 A Brief Economic History of Beer
Authors: Poelmans Eline , Swinnen Johan F. M.
Published: January 2012

This chapter presents a brief economy history of the evolution of beer production and consumption and the industrial organization of breweries. It discusses first the discovery and use of beer in ancient history, and the functioning of monasteries as centres of the beer economy in the early Middle Ages. It then presents an analysis of the innovation and taxation in brewing in the Middle Ages which triggered the decline of monasteries and growth of commercial breweries in Early Modern Times. It analyzes the globalization and new competition for beer in the Early Modern Times, as well as the scientific discoveries and the development of modern brewing in the 18th and 19th centuries. Finally, the growth and decline of different types of beer and the consolidation and globalization of breweries in the last two centuries are discussed.
Supplemental Nutrition Assistance Program Dynamics and Employment Transitions: The Role of Employment Instability
Authors: Mabli James , Ohls James C.
Published: January 2012

Employment transitions have been shown to be an important predictor of the decision to either enter or exit the Supplemental Nutrition Assistance Program (SNAP). However, little is known about how the associations between losing a job and entering the program, or between obtaining a job and leaving the program differ by individuals' more long‐term employment experiences. This article uses a sample from the Survey of Income and Program Participation, collected from 2001 to 2003, to examine how long‐term instability in employment affects the association between employment transitions and the decision to enter and exit SNAP. Empirical models of program entry and exit are estimated for a full sample and for family subgroups of particular interest to program policy‐makers. Our results provide evidence that employment changes are more strongly associated with program entry and exit for individuals who are less accustomed to experiencing fluctuations in employment than those who are more accustomed to experiencing these fluctuations.
Characterizing variation in Northwest Atlantic fish-stock abundance
Authors: Rothschild Brian J. , Jiao Yue
Published: January 2012

Rothschild, B. J., and Jiao, Y. 2012. Characterizing variation in Northwest Atlantic fish-stock abundance. – ICES Journal of Marine Science, 69: 913–922. Catch-per-tow indices obtained by research vessels for the years 1963–2009 from NAFO statistical areas 4W, 4X, 5Y, and 5Z were studied to determine how fish “apparent abundance” in the decade 2000–2009 differed from the long-term time-series. Cluster analysis of normalized catch-per-tow data indicated that the abundance and species composition of stocks in each statistical area changed dramatically over the 50-year period. There were decreases in thorny skate, ocean pout, cusk, witch flounder, and monkfish and increases in herring, haddock, northern shrimp, and spiny dogfish. Cluster analysis suggested that these decreases and increases were not gradual, but abrupt, and that these abrupt decreases and increases were concentrated in the decade of the 1980s. Observations of abrupt change were supported by regression-tree analysis of individual stocks. Examination of the interrelationship among abundance indices from different stocks by Bonferroni-adjusted correlation coefficients showed that the abundance trajectories of most stocks were uncorrelated. It appears that the set of population transitions during the decade of the 1980s was a dominant event in the statistical time-series.
Neuro‐invasion by a ‘Trojan Horse’ strategy and vasculopathy during intrauterine flavivirus infection
Authors: Bielefeldt‐Ohmann Helle , Smirnova Natalia P. , Tolnay Airn‐Elizabeth , Webb Brett T. , Antoniazzi Alfredo Q. , van Campen Hana , Hansen Thomas R.
Published: January 2012

The central nervous system (CNS) is a major target of several important human and animal viral pathogens causing congenital infections. However, despite the importance of neuropathological outcomes, for humans in particular, the pathogenesis, including mode of neuro‐invasion, remains unresolved for most congenital virus infections. Using a natural model of congenital infection with an RNA virus, bovine viral diarrhoea virus in pregnant cattle, we sought to delineate the timing and mode of virus neuro‐invasion of and spread within the brain of foetuses following experimental respiratory tract infection of the dams at day 75 of pregnancy, a time of maximal risk of tissue pathology without foetal death. Virus antigen was first detected in the foetal brains 14 days postinfection of dams and was initially restricted to amoeboid microglial cells in the periventricular germinal layer. The appearance of these cells was preceded by or concurrent with vasculopathy in the same region. While the affected microvessels were negative for virus antigen, they expressed high levels of the type I interferon‐stimulated protein ISG15 and eventually disappeared in parallel with the appearance of microcavitary lesions. Subsequently, the virus spread to neurons and other glial cells. Our findings suggest that the virus enters the CNS via infected microglial precursors, the amoeboid microglial cells, in a ‘Trojan horse’ mode of invasion and that the microcavitary lesions are associated with loss of periventricular microvasculature, perhaps as a consequence of high, unrestricted induction of interferon‐regulated proteins.
Modification of pharmacokinetic and abuse‐related effects of cocaine by human‐derived cocaine hydrolase in monkeys
Authors: Schindler Charles W. , Justinova Zuzana , Lafleur David , Woods Doug , Roschke Viktor , Hallak Hussein , Sklair‐Tavron Liora , Redhi Godfrey H. , Yasar Sevil , Bergman Jack , Goldberg Steven R.
Published: January 2012

Although substantial research effort has focused on developing pharmacological treatments for cocaine abuse, no effective medications have been developed. Recent studies show that enzymes that metabolize cocaine in the periphery, forestalling its entry into the brain, can prevent cocaine toxicity and its behavioral effects in rodents. Here we report on effects of one such enzyme (Albu‐CocH) on the pharmacokinetic and behavioral effects of cocaine in squirrel monkeys. Albu‐CocH was developed from successive mutations of human butyrylcholinesterase (BChE) and has 1000‐fold greater catalytic activity against cocaine than naturally occurring BChE. Pharmacokinetic studies showed that Albu‐CocH (5 mg/kg) had a half‐life of 56.6 hours in squirrel monkeys. In these studies, plasma levels of cocaine following i.v. 1 mg/kg cocaine were reduced 2 hours after administration of Albu‐CocH, whereas plasma levels of the cocaine metabolite ecgonine methyl ester were increased. These effects were still evident 72 hours following Albu‐CocH administration. In behavioral experiments in monkeys, pre‐treatment with 5 mg/kg Albu‐CocH dramatically decreased self‐administration of a reinforcing dose of i.v. cocaine (30 µg/kg/injection) for over 24 hours. Pre‐treatment with 5 mg/kg Albu‐CocH also attenuated the reinstatement of extinguished cocaine self‐administration by an i.v. priming injection of cocaine (0.1 or 0.3 mg/kg) and, in separate studies, attenuated the discriminative‐stimulus effects of cocaine. The ability of Albu‐CocH to attenuate the abuse‐related effects of cocaine in squirrel monkeys indicates that further investigation of BChE mutants as potential treatment for cocaine abuse and toxicity is warranted.
Expression of β‐tubulin isotypes in classical Hodgkin's lymphoma
Authors: Choi Jung‐Woo , Lee Ju‐Han , Kim Young‐Sik
Published: January 2012

Microtubules consist of heterodimers of α‐ and β‐tubulin. Aberrant expression of specific β‐tubulin isotype is associated with resistance to chemotherapy in malignant tumors. In this study, we examined the expressions of β‐tubulin isotypes in classical Hodgkin's lymphoma (cHL) by immunohistochemistry. Among the β‐tubulin isotypes, class II β‐tubulin (31/34, 91%) was most frequently overexpressed in the cytoplasm of almost all Hodgkin's and Reed‐Sternberg (HRS) cells, followed by class I β‐tubulin (18/34, 53%) and class III β‐tubulin (12/34, 35%). Class IV β‐tubulin was not expressed in any cHL case. Class I β‐tubulin was expressed in the background lymphoid cells as well as the HRS cells. Thus, our results indicate that class II β‐tubulin may be very useful for immunohistochemical diagnosis of cHL, and provide valuable information for the potential application of β‐tubulin isotype‐specific targeting.
Improvement of light fastness of natural dye: effect of ultraviolet absorbers containing benzotriazolyl moiety on the photofading of red carthamin
Authors: Oda Hironori
Published: January 2012

While the contribution of ultraviolet absorbers to synthetic dyes has been investigated by several workers, there have been few studies pertaining to the use of functional ultraviolet absorbers as a means of improving the light fastness of natural dyes. In this paper, numerous potential ultraviolet absorbers were prepared to prolong the life of natural dye carthamin. The effects of these compounds in reducing photofading were examined on a polymer substrate. The use of commercial ultraviolet absorbers was not necessarily useful in improving the light fastness of the colour. However, benzophenone‐type ultraviolet absorbers containing a built‐in ultraviolet absorber moiety markedly retarded the photofading rate. It is proposed that 2,2′,4,4′‐tetrahydroxy‐5‐methylbenzotriazolylbenzophenone and its derivatives may be used as effective stabilisers in the fading of natural dyes.