bluuebunny/crossref_metadata_2025_split huggingface dataset:
Retinal input influences the size and corticocortical connectivity of visual cortex during postnatal development in the ferret
Authors: Bock A.S. , Kroenke C.D. , Taber E.N. , Olavarria J.F. 
Published: August 2011

AbstractRetinal input plays an important role in the specification of topographically organized circuits and neuronal response properties, but the mechanism and timing of this effect is not known in most species. A system that shows dramatic dependence on retinal influences is the interhemispheric connection through the corpus callosum. Using ferrets, we analyzed the extent to which development of the visual callosal pattern depends on retinal influences, and explored the period during which these influences are required for normal pattern formation. We studied the mature callosal patterns in normal ferrets and in ferrets bilaterally enucleated (BE) at postnatal day 7 (P7) or P20. Callosal patterns were revealed in tangential sections from unfolded and flattened brains following multiple injections of horseradish peroxidase in the opposite hemisphere. We also estimated the effect of enucleation on the surface areas of striate and extrastriate visual cortex by using magnetic resonance imaging (MRI) data from intact brains. In BEP7 ferrets we found that the pattern of callosal connections was highly anomalous and the sizes of both striate and extrastriate visual cortex were significantly reduced. In contrast, enucleation at P20 had no significant effect on the callosal pattern, but it still caused a reduction in the size of striate and extrastriate visual cortex. Finally, retinal deafferentation had no significant effect on the number of visual callosal neurons. These results indicate that the critical period during which the eyes influence the development of callosal patterns, but not the size of visual cortex, ends by P20 in the ferret. J. Comp. Neurol. 520:914–932, 2012. © 2011 Wiley Periodicals, Inc.
Onecut 1 and Onecut 2 are potential regulators of mouse retinal development
Authors: Wu Fuguo , Sapkota Darshan , Li Renzhong , Mu Xiuqian 
Published: August 2011

AbstractOur current study focuses on the expression of two members of the onecut transcription factor family, Onecut1 (Oc1) and Onecut2 (Oc2), in the developing mouse retina. By immunofluorescence staining, we found that Oc1 and Oc2 had very similar expression patterns throughout retinal development. Both factors started to be expressed in the retina at around embryonic day (E) 11.5. At early stages (E11.5 and E12.5), they were expressed in both the neuroblast layer (NBL) and ganglion cell layer (GCL). As development progressed (from E14.5 to postnatal day [P] 0), expression diminished in the retinal progenitor cells and became more restricted to the GCL. By P5, Oc1 and Oc2 were expressed at very low levels in the GCL. By co‐labeling with transcription factors known to be involved in retinal ganglion cell (RGC) development, we found that Oc1 and Oc2 had extensive overlap with Math5 in the NBL, and that they completely overlapped with Pou4f2 and Isl1 in the GCL, but only partially in the NBL. Co‐labeling of Oc1 with cell cycle markers confirmed that Oc1 was expressed in both proliferating retinal progenitors and postmitotic retinal cells. In addition, we demonstrated that expression of Oc1 and Oc2 did not require Math5, Isl1, or Pou4f2. Thus, Oc1 and Oc2 may regulate the formation of RGCs in a pathway independent of Math5, Pou4f2, and Isl1. Furthermore, we showed that Oc1 and Oc2 were expressed in both developing and mature horizontal cells (HCs). Therefore the two factors may also function in the genesis and maintenance of HCs. J. Comp. Neurol. 520:952–969, 2012. © 2011 Wiley Periodicals, Inc.
Metamorphosis of a clock: Remodeling of the circadian timing system in the brain of Rhodnius prolixus (Hemiptera) during larval‐adult development
Authors: Vafopoulou Xanthe , Steel Colin G.H. 
Published: August 2011

AbstractThe rhythmic phenomena expressed by organisms change over their lifetimes, but little is known of accompanying reorganization of the central circadian timing system in the brain. Especially dramatic changes in overt rhythms and morphology occur during transformation of larval insects into the adult form (metamorphosis). In Rhodnius prolixus, both the physiology of metamorphosis and its hormonal control are known in detail. Here we report changes in the brain timing system as revealed by pigment dispersing factor immunohistochemistry and confocal microscopy. Most of the features of the larval system are retained, but new clock cells differentiate and the arborizations of their axons increase in complexity, as do pathways connecting the lateral (LNs) and dorsal (DNs) groups of clock neurons. Early in metamorphosis, the LNs increase from 8 to 11 in number, becoming five small and six large LNs. Two large LNs then migrate to new positions in the protocerebrum. Another clock cell differentiates in the posterior protocerebrum. Each change occurs at a characteristic concentration of the ecdysteroid molting hormones that regulate metamorphosis. Clock cell axons invade the mushroom body and corpus allatum and travel down the ventral nerve cord. New overt rhythms develop during metamorphosis, in which these structures participate. The neuroendocrine cells of the brain receive more extensive branches of clock cell axons than in larvae. These increases in size and complexity of the circadian system during metamorphosis imply a greater complexity and diversity of outputs from it to both behavioral and hormonal rhythms in the adult. J. Comp. Neurol. 520:1146–1164, 2012. © 2011 Wiley Periodicals, Inc.
ON ganglion cells are intrinsically photosensitive in the tiger salamander retina
Authors: Rajaraman Kaveri 
Published: August 2011

AbstractIntrinsically photosensitive retinal ganglion cells (ipRGCs) have been well characterized in mammalian systems, both morphologically and electrophysiologically. They show slow, sustained responses to bright light in the absence of photoreceptor‐based input, mediated by the photopigment melanopsin. Only one mammalian melanopsin gene is expressed in a small fraction of the retinal ganglion cell population, but there are two genes for melanopsin among nonmammalian vertebrates that are widely expressed in a variety of retinal and extraretinal cell types, along with other photosensitive pigments. The current study provides an electrophysiological study of ipRGCs in the larval tiger salamander (Ambystoma tigrinum), a nonmammalian vertebrate with a well‐characterized retina. The results show that the ipRGC population is equivalent to the ON ganglion cell population in the tiger salamander retina. This sheds light on the evolutionary trajectory and functional significance of intrinsic photosensitivity through the vertebrate lineage and also affects our understanding of ON cell activity and development. We have characterized the nature of the intrinsic responses of the ON cell population, compared intrinsic and synaptically based receptive fields, and quantified the spectrum of the intrinsic activity. A wider action spectrum of intrinsic photosensitivity was obtained than would be expected for a single opsin photopigment, suggesting the expression of multiple photopigments in the salamander ipRGC. J. Comp. Neurol., 2012. © 2011 Wiley Periodials, Inc.
Quantum dynamics in continuum for proton transport II: Variational solvent–solute interface
Authors: Chen Duan , Chen Zhan , Wei Guo‐Wei 
Published: August 2011

SUMMARYProton transport plays an important role in biological energy transduction and sensory systems. Therefore, it has attracted much attention in biological science and biomedical engineering in the past few decades. The present work proposes a multiscale/multiphysics model for the understanding of the molecular mechanism of proton transport in transmembrane proteins involving continuum, atomic, and quantum descriptions, assisted with the evolution, formation, and visualization of membrane channel surfaces. We describe proton dynamics quantum mechanically via a new density functional theory based on the Boltzmann statistics, while implicitly model numerous solvent molecules as a dielectric continuum to reduce the number of degrees of freedom. The density of all other ions in the solvent is assumed to obey the Boltzmann distribution in a dynamic manner. The impact of protein molecular structure and its charge polarization on the proton transport is considered explicitly at the atomic scale. A variational solute–solvent interface is designed to separate the explicit molecule and implicit solvent regions. We formulate a total free‐energy functional to put proton kinetic and potential energies, the free energy of all other ions, and the polar and nonpolar energies of the whole system on an equal footing. The variational principle is employed to derive coupled governing equations for the proton transport system. Generalized Laplace–Beltrami equation, generalized Poisson–Boltzmann equation, and generalized Kohn–Sham equation are obtained from the present variational framework. The variational solvent–solute interface is generated and visualized to facilitate the multiscale discrete/continuum/quantum descriptions. Theoretical formulations for the proton density and conductance are constructed based on fundamental laws of physics. A number of mathematical algorithms, including the Dirichlet‐to‐Neumann mapping, matched interface and boundary method, Gummel iteration, and Krylov space techniques are utilized to implement the proposed model in a computationally efficient manner. The gramicidin A channel is used to validate the performance of the proposed proton transport model and demonstrate the efficiency of the proposed mathematical algorithms. The proton channel conductances are studied over a number of applied voltages and reference concentrations. A comparison with experimental data verifies the present model predictions and confirms the proposed model. Copyright © 2011 John Wiley & Sons, Ltd.
Cognitive–behavioural group therapy versus guided self‐help for compulsive buying disorder: A preliminary study
Authors: Müller A. , Arikian A. , de Zwaan M. , Mitchell J.E. 
Published: August 2011

Compulsive buying (CB) is defined as extreme preoccupation with buying/shopping and frequent buying that causes substantial negative psychological, social, occupational and financial consequences. There exists preliminary evidence that group cognitive–behavioural therapy (CBT) is effective in the treatment of CB. The present pilot study made a first attempt to compare group CBT for CB with telephone‐guided self‐help (GSH). Fifty‐six patients were allocated randomly to one of the three conditions: (1) group CBT (n = 22); (2) GSH (n = 20); and (3) a waiting list condition (n = 14). The results indicate that face‐to‐face group CBT is superior not only to the waiting list condition but also to GSH. Patients who received GSH tended to have more success in overcoming CB compared with the waiting list controls. Given the sample size, the results must be considered as preliminary and further research is needed to address the topic whether GSH also could be a helpful intervention in reducing CB. Copyright © 2011 John Wiley & Sons, Ltd.Key Practitioner Message

Group cognitive–behavioural therapy is effective in the treatment of compulsive buying and superior to telephone‐guided self‐help.
Preliminary data suggest that individuals who received telephone‐guided self‐help reported some improvement in compulsive buying compared with a waiting list condition.
Further research is needed to investigate whether guided‐self help is effective in overcoming compulsive buying.
The importance of residual renal function in peritoneal dialysis
Authors: Curran Simon P. , Bargman Joanne M. 
Published: August 2011

AbstractPeritoneal dialysis (PD) is an important form of renal replacement therapy. The contribution of residual renal function (RRF) to the adequacy of PD is well recognized, but of greater importance is the association it has with reduced mortality and other important outcomes. This article reviews the evidence linking RRF with these outcomes, and discusses how we can best preserve it. Dial. Transplant. © 2011 Wiley Periodicals, Inc.
Invasion of shrublands by exotic grasses: ecohydrological consequences in cold versus warm deserts
Authors: Wilcox Bradford P. , Turnbull Laura , Young Michael H. , Williams C. Jason , Ravi Sujith , Seyfried Mark S. , Bowling David R. , Scott Russell L. , Germino Matthew J. , Caldwell Todd G. , Wainwright John 
Published: August 2011

ABSTRACTAcross the globe, native savannas and woodlands are undergoing conversion to exotic grasslands. Here we summarize the current state of knowledge concerning the ecohydrological consequences of this conversion for the cold deserts (Great Basin, Colorado Plateau) and the warm deserts (Mojave, Sonoran, Chihuahuan) of North America. Our analysis is based on a synthesis of relevant literature, complemented by simulation modelling with a one‐dimensional, soil water redistribution model (HYDRUS‐1D) and a hillslope runoff and erosion model (MAHLERAN). When shrublands are invaded by grasses, many changes take place: rooting depths, canopy cover, species heterogeneity, water use, and fire regimes are radically altered. These changes then have the potential to alter key ecohydrological processes. With respect to the processes of runoff and erosion, we find that grass invasion influences cold and warm deserts in different ways. In cold deserts, runoff and erosion will increase following invasion; in particular, erosion on steep slopes (>15%) will be greatly accelerated following burning. In addition, evapotranspiration (ET) will be lower and soil water recharge will be higher—which after several decades could affect groundwater levels. For warm deserts, grass invasion may actually reduce runoff and erosion (except for periods immediately following fire), and is likely to have little effect on either ET fluxes or soil water. Significant gaps in our knowledge do remain, primarily because there have been no comprehensive studies measuring all components of the water and energy budgets at multiple scales. How these changes may affect regional energy budgets, and thus weather patterns, is not yet well understood. Copyright © 2011 John Wiley & Sons, Ltd.
Interpreting the groundwater attributes influencing the distribution patterns of groundwater‐dependent vegetation in northwestern China
Authors: Zhu Juntao , Yu Jingjie , Wang Ping , Zhang Yichi , Yu Qiang 
Published: August 2011

ABSTRACTGroundwater‐dependent vegetation (GDV) must have access to groundwater to maintain their growth and function. GDV distribution patterns are an important issue in arid vegetation ecology. Using groundwater attributes to explore the distribution patterns of GDV have been very limited. In this article, we selected the Ejina Desert Oasis as an area to investigate GDV and groundwater attributes. Twenty plant species and 31 plant plots of data were collected. Two‐way indicator species analysis (TWINSPAN) was performed to determine GDV types. Detrended correspondence analysis (DCA) and detrended canonical correspondence analysis (DCCA) were performed to analyse the relationships between GDV and groundwater attributes. The results indicated that (1) six plant community types were classified by TWINSPAN; (2) DCA ordination analyses showed that the groundwater depth (Dep) was the main factor restricting the distribution patterns of GDV, and the distribution of the dominant species and corresponding vegetation types had strong similarities; (3) in the DCCA diagram, the first axis represented variations of Dep, while the second axis was related to the pH values; (4) with increased Dep, the community types made the transition from I to VI; and (5) the DCCA diagram was similar to the DCA. However, the distribution patterns of GDV were more compact in the DCCA, while the DCA showed that each association group appeared within a limited range and had a clear border against other communities. This study shows that ordination methods can be used to explain the relationships between the distribution patterns of GDV and groundwater attributes. Copyright © 2011 John Wiley & Sons, Ltd.
Effect of Electrode Dimensionality and Morphology on the Performance of Cu2Sb Thin Film Electrodes for Lithium‐Ion Batteries
Authors: Trahey Lynn , Kung Harold H. , Thackeray Michael M. , Vaughey John T. 
Published: August 2011

AbstractAlthough graphitic carbons have been commercially used in lithium‐ion batteries for many years, their low crystallographic density limits their use in applications where space is at a premium. Among the alternative anode materials being considered for these applications are Zintl phases and intermetallic insertion anodes. Historically, main‐group‐metal‐based anode materials have had problems with respect to volume expansion experienced on lithiation and its effect on cycle life. In this paper, we report the role of morphology and electrode dimensionality in extending the cycle life of the intermetallic insertion anode Cu2Sb. We have found that controlling the surface area of the active material and building internal volume into the electrode structure significantly decreases the capacity fade on cycling. The decrease in fade rate may be due to the active material gradient identified within the structure produced by the electrodeposition process. This enhancement in cycling can be attributed to keeping the displaced copper closer to the active particles and to reducing the diffusion distances within the electrode.
Organic Nanostructures with Controllable Morphology Fabricated from Ferrocene–Porphyrin Derivatives: Effect of Metal–Ligand Coordination on the Morphology, Dimensions, and Semiconductor Properties of Self‐Assembled Nanostructures
Authors: Zhu Peihua , Ma Pan , Wang Yan , Wang Quanbo , Zhao Xian , Zhang Xiaomei 
Published: August 2011

AbstractTwo new ferrocene–porphyrin derivatives, namely 5,15‐bis(ferrocenyl)‐10,20‐bis(4‐nitrophenyl)porphyrin (1) and its nickel congener 5,15‐bis(ferrocenyl)‐10,20‐bis(4‐nitrophenyl)porphyrinatonickel (2) have been designed, synthesized, and characterized. Their self‐assembly properties have been comparatively studied by electronic absorption and FTIR spectroscopy, TEM, SEM, XRD, and X‐ray photoelectron spectroscopy (XPS). Metal‐free 1 self‐assembles into nanospheres with diameters in the range of 30–50 nm, depending mainly on intermolecular π–π interactions. In contrast, the coordination of nickel to 1 introduces an additional Ni–O coordination bond between the nitryl group of one molecule of 2 and the nickel center of the neighboring 2 unit, which, in cooperation with the intermolecular π–π interaction, induces the formation of nanobelts (ca. 50–300 μm length, 10–50 nm width) during the self‐assembly process of 2.
P4S3 and P,P′ or N,N′ Donors as Competitive Building Blocks in Copper(I) Coordination Polymers
Authors: Biegerl Andreas , Piryazev Dmitry , Scheer Manfred , Wachter Joachim , Virovets Alexander , Zabel Manfred 
Published: August 2011

AbstractThe synthesis and characterization of hybrid polymers combining organic P,P′ (dppe) or N,N′ (pyrazine) ligands and inorganic donors (P4S3) as cross‐linkers between copper(I) halide aggregates is described. As a simple model system the reaction of a mixture of P4S3, PEt3, and CuX (X = Cl, Br, I) was studied. According to X‐ray diffraction analysis, pseudotetrahedral monomers [CuX(PEt3)2(P4S3)] (1–3) were formed, in which P4S3 coordinates through the apical phosphorus atom. Layering a mixture of P4S3, Ph2PCH2CH2PPh2 (dppe), and toluene with CuCl in MeCN under diffusion conditions gives 1D‐[CuCl(dppe)(MeCN)] (6), which contains (Cu2Cl2)2(μ‐dppe)2 clusters linked by another dppe ligand. The analogous reaction with CuI gives 1D‐[CuI(P4S3)(dppe)] (7), which is built up of alternating trans‐(Cu2I2)(P4S3)2 units and dppe linkers. Hybrid polymers 2D‐[CuX(P4S3)(dppe)] [X = Br (8), I (9)] are formed if CH2Cl2 is used instead of toluene. The 2D structures of 8 and 9 may be derived from that of 7 by connecting neighboring (CuX)(dppe) strands with pairs of inversely coordinated P4S3 cages. Replacement of dppe by pyrazine (pyz) yields 3D‐[(CuCl)4(P4S3)2(pyz)] (10) and 3D‐[(CuBr)3(P4S3)(pyz)] (12), respectively. The structure of 10 comprises a 3D network composed of alternating, linked 2D‐[(CuCl)2(P4S3)] and 2D‐[CuCl(pyz)] layers. The structure of 12 contains cradles built from opposing (CuBr)6 rings and pairwise pyz and P4S3 bridges. These cradles are organized into a 3D framework by condensation of the (CuBr)6 rings, and the layers formed are linked by additional pyz molecules. The resulting voids are occupied by toluene molecules. The behavior of P4S3 and P,P′ or N,N′ ligands as competitive building blocks is also expressed by the formation of binary P4S3/CuX or pyz/CuX polymers.
A Lewis Acid Mediated Schmidt Reaction of Benzylic Azide: Synthesis of Sterically Crowded Aromatic Tertiary Amines
Authors: Murali Annamalai , Puppala Manohar , Varghese Babu , Baskaran Sundarababu 
Published: August 2011

AbstractAn efficient one‐pot synthesis of sterically hindered aromatic tertiary amines through Lewis acid induced intermolecular Schmidt reaction of benzylic azides is described. In the presence of EtAlCl2, benzylic azide underwent a smooth Schmidt reaction to give the corresponding iminium ion, which, upon reduction with NaBH4 in situ, afforded the tertiary amine. The effects of substituents on the aromatic ring and the steric effects of the alkyl side chain have also been studied.
Raising HDL‐C through cholesteryl ester transfer protein inhibition
Authors: Viljoen Adie , Wierzbicki Anthony 
Published: August 2011

AbstractPlasma concentrations of high‐density lipoprotein cholesterol (HDL‐C) and its major protein component apolipoprotein (apo) A‐I are strongly inversely correlated with cardiovascular risk, leading to the notion that therapy to increase HDL‐C and apoA‐I concentrations would be antiatherosclerotic and protective against cardiovascular disease (CVD) events.1,2 In this article, the authors discuss how inhibition of cholesteryl ester transfer protein (CETP) could potentially lead to an increase in HDL‐C with a subsequent reduction in CVD events, a hypothesis being tested by the development of the drugs anacetrapib and dalcetrapib.
Representation of perceived sound valence in the human brain
Authors: Viinikainen Mikko , Kätsyri Jari , Sams Mikko 
Published: August 2011

AbstractPerceived emotional valence of sensory stimuli influences their processing in various cortical and subcortical structures. Recent evidence suggests that negative and positive valences are processed separately, not along a single linear continuum. Here, we examined how brain is activated when subjects are listening to auditory stimuli varying parametrically in perceived valence (very unpleasant–neutral–very pleasant). Seventeen healthy volunteers were scanned in 3 Tesla while listening to International Affective Digital Sounds (IADS‐2) in a block design paradigm. We found a strong quadratic U‐shaped relationship between valence and blood oxygen level dependent (BOLD) signal strength in the medial prefrontal cortex, auditory cortex, and amygdala. Signals were the weakest for neutral stimuli and increased progressively for more unpleasant or pleasant stimuli. The results strengthen the view that valence is a crucial factor in neural processing of emotions. An alternative explanation is salience, which increases with both negative and positive valences. Hum Brain Mapp 33:2295–2305, 2012. © 2011 Wiley Periodicals, Inc.