bluuebunny/crossref_metadata_2025 huggingface dataset:
Determination of Coupling Signs 1J(119Sn, 15N ) and 2J(119Sn, 117Sn) in Trimethylstannylamines
Authors: Wrackmeyer Bernd , Weidinger Jürgen , Nöth Heinrich , Storch Wolfgang , Seifert Thomas , Vosteen Martina
Published: February 2015

The l5N-labelled trimethylstannylamines 1 - 3 [(Me3Sn)3N, (Me3Sn)2NPh, (Me3Sn)2NBCgHi4 (BCgHi4 = 9-borabicyclo[3.3.0]nonyn and the non-labelled 4, Me3Sn-N(BC8Hi4)2 , were prepared and studied by 1H, 1C, 15N and 119Sn NMR. The 15N ultrahigh resolution NMR spectra of 1 revealed otherwise unobserved parameters such as 2J(15N ,Sn ,13C ) and the isotope induced chemical shift 2Δ12/13C(15N). 119Sn NMR spectra of 1, recorded under similar conditions, also show new parameters such as 3J(119Sn,N,Sn,13C) which are not resolved in the non-labelled derivative. By using various types o f two-dimensional heteronuclear shift correlations, absolute coupling signs of 1J(119Sn,15N) (all < 0) in 1 - 3 were determined. By the same techniques it proved possible to confirm the negative sign o f :7(Sn,Sn) (-195.4 Hz) in 1. In contrast, the coupling constants 2J(Sn,Sn) for 2 (+71.7) and 3 (+62.0) possess a positive sign. This sign inversion, observed here for the first time for apparently similar compounds, demonstrates the enormous influence of substituents on the nature of the lone pair of electrons at the nitrogen atom. It also shows that these experiments for sign determinations of coupling constants are necessary in order to interpret these data correctly.
Indium partiell in tetraedrischer Sauerstoffkoordination in BaIn2Zn3O7. Eine Betrachtung zum Ba2Ln2Zn8O13/BaLnAlZn3O7 -Typ / Partial Tetrahedral Oxygen Coordination of Indium in BaIn2Zn3O7. A Consideration of the Ba2Ln2Zn8O13/BaLnAlZn3O7 Type
Authors: Sfreddo O. , Müller-Buschbaum Hk.
Published: February 2015

Single crystals of BaIn2Zn3O7 have been prepared by solid state reaction and crystallization from flux. X-ray investigations led to hexagonal symmetry, space group C4
6v-P63mc, lattice constants a = 6.342(1), c = 10.282(1) Å, Z = 2. BaIn2Zn3O7 shows tetrahedral positions statistically occupied by In3+ and Zn2+. The crystal structure is isotypic to Ba2Ln2Zn8O13 and BaLnAlZn3O7. A discussion of the related compounds is given.
Zur Kenntnis eines Vanadyl-Oxocuprat-Phosphats CaCu(VO)(PO4)2 mit Cu2+ auf Positionen der VO2+-Ionen und einer kupferreicheren Phase CaCu1,13(VO)0,87(PO4)2 / On an Vanadyl Oxocuprate Phosphate CaCu(VO)(PO4)2 Containing Cu2+ at Positions of VO2+ Ions and a Copper Rich Phase CaCu1.13(VO)0.87(PO4)2
Authors: Meyer S. , Müller-Buschbaum Hk.
Published: February 2015

Single crystals of CaCu(VO)(PO4)2 (I) and CaCu1.13(VO)0.87(PO4)2 (II) have been prepared using solid state reactions in closed and evacuated quartz tubes. X-ray characterization led to orthorhombic symmetry, space group D16
2h-Pnma, lattice constants a, b, c (I): 9.708( 1), 9.603( 1), 6.913(1) Å and (II); 9.700(1), 9.614(1), 6.896(1) Å, Z = 4. Strongly deformed CaO8 cubes are connected by planar CuO4 polygons or square VO1+4 pyramids. Short V-O distances are features of VO2+ groups. Two point positions are occupied in a disordered manner by Cu2+ and VO2+. The replacement of Cu2+ by VO2+ at one position depends on the ratio VO2+ : Cu2+ at the neighbouring position, since otherwise there would be collisions of the apical oxygen atoms of neighbouring VO1+4 pyramids.
Verknüpfung von (TeO6)6- und (TeO6)3(NiO6)3-Sechsringen durch TeNiO9-Oktaederdoppel in Pb3Ni4,5Te2,5O15 / Connection of (TeO6)6 and (TeO6)3(NiO6)3 Hexagons by TeNiO9 Octahedra Double in Pb3Ni4,5Te2,5O15
Authors: Wedel B. , Sugiyama K. , Müller-Buschbaum Hk.
Published: February 2015

Single crystals of Pb3Ni4.5Te2.5O15 have been prepared by heating pellets of mixtures of PbO, TeO2 and nickel hydroxide carbonate to 730 °C in air. X-ray investigations led to hexagonal symmetry, space group d6
6-P6322, lattice constants a = 10.2589(1), c = 13.554(5), Z = 4. Typical features of the crystal structure are face sharing TeNiO9 octahedra doubles and planes of connected (TeO6)6 and (TeO6)3(NiO6)3 hexagons. The one-sided coordination of lead by oxygen is complemented by the lone pair of electrons. The lone pair positions are estimated by calculations of the Coulomb terms of lattice energy.
Preparation and X-Ray Structure of 3,5-Dimethyl-1,4-dichloro-1,2,6- thiadiazine-1-oxide
Authors: Chivers Tristram , Li Xiaorong , Parvez Masood
Published: February 2015

The title compound was obtained by the reaction of 3,5-dimethyl-2H-1,2,6-thiadiazine-1,1-dioxide with PCI5 in chloroform. It crystallizes in the monoclinic system, space group P21/c, a = 7.521(7) Å, b = 8.400(4) Å, c = 13.908(4) Ä, β = 100.35(4)°, V = 864.4(8) Å3, and Z = 4. The S(VI) atom lies 0.43 Å out of the plane of the π-delocalized NCCCN unit. The mean S-N bond distance is 1.569(3) Å.
Pentafluoro[(4-methyl-1,4-bisazoniacy clohex-1 -yl)methy 1] germanate Hydrate: Synthesis and Crystal Structure of a Zwitterionic λ6Ge-Germanate with a GeF5C Framework
Authors: Tacke Reinhold , Heermann Joachim , Pülm Melanie
Published: February 2015

The zwitterionic (molecular) λ6Ge-germanate pentafluoro[(4-methyl-1,4-bisazoniacyclohexl-yl)methyl]germanate (5) was synthesized by reaction of 1-methyl-4-[(trimethoxygermyl) methyl]piperazine (8) with HF (molar ratio 1:5) in a mixture of water and ethanol at 0 °C and isolated as the hydrate 5 · H2O. The zwitterion 5 is characterized by the presence of a hexacoordinate (formally twofold negatively charged) germanium atom and two tetracoordinate (formally positively charged) nitrogen atoms. Compound 5 · H2O was structurally characterized by single-crystal X-ray diffraction. Crystal data are as follows: C6H17F5GeN2O , triclinic space group P1̄ (no. 2), a = 7.5228(11) Å, b = 12.174(2) Å, c = 12.3041(14) Å, α = 73.74(2)°, β = 82.44(2)°, γ = 74.762(10)°, V = 1041.7(2) Å3, T = 173(2) K, Z = 4, R1 = 0.0227. There are one pair each of crystallographically independent zwitterions 5 and water molecules in the asymmetric unit, the structures of the zwitterions being very similar. Their coordination polyhedra around the germanium atoms are slightly distorted octahedra.
In situ Neutron Diffraction on DxNb2O5
Authors: Unruh Tobias , Schwitzgebel Günter , Ritter Clemens
Published: February 2015

DxNb2O5 is thermodynamically unstable. Therefore, neutron diffraction measurements were performed in the electrochemical cell used for the intercalation of deuterium into sintered Nb2O5 powder samples. Diffraction patterns were recorded at equilibrium potentials of -443, -428, -332 and -197 mV vs. NHE (corresponding to x = 0.232, x = 0.23, x = 0.21 and x = 0.06). The structural changes in Nb2O5 caused by the deuterium insertion are small but could be determined reproducibly. The lattice parameters of the host lattice exhibit a characteristic dependence on the deuterium content of the bronze. A model has been developed for the partially inhomogeneous distribution of the deuterium in the Nb2O5 unit cell, which explains the changes of the peak intensities observed in the low angle region (6° ≤ 2θ ≤ 18°)

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Kristallstruktur von 1,1'-Dimethyl-4,4'-bipyridinium-octachlorodiantimonat(III) / Crystal Structure of 1,1'-Dimethyl-4,4'-bipyridinium-octachlorodiantimonate(III)
Authors: Jaschinski Bernd , Blachnik Roger , Reuter Hans
Published: February 2015

The title compound was prepared by reaction of SbCl3 with 1,1′-dimethyl-4,4′-bipyridinium-chloride in methanol. The single crystal structure gave the following data: [C12H14N2][Sb2Cl8] (1) space group PI, Nr. 1, with a = 570.68(7) pm, b = 938.57(14) pm, c = 1174.27(11)pm, α = 66.72(9)°, β = 89.304(12)°, γ = 78.684(11)°, and Z = 1. The compound has a small SHG effect and a phase transition at 272 °C with an enthalpy of transition of 6.54 kJ mol-1 .
Norepinephrine Is Necessary for Experience-Dependent Plasticity in the Developing Mouse Auditory Cortex
Authors: Shepard Kathryn N. , Liles L. Cameron , Weinshenker David , Liu Robert C.
Published: February 2015

Critical periods are developmental windows during which the stimuli an animal encounters can reshape response properties in the affected system to a profound degree. Despite this window's importance, the neural mechanisms that regulate it are not completely understood. Pioneering studies in visual cortex initially indicated that norepinephrine (NE) permits ocular dominance column plasticity during the critical period, but later research has suggested otherwise. More recent work implicating NE in experience-dependent plasticity in the adult auditory cortex led us to re-examine the role of NE in critical period plasticity. Here, we exposed dopamine β-hydroxylase knock-out (Dbh−/−) mice, which lack NE completely from birth, to a biased acoustic environment during the auditory cortical critical period. This manipulation led to a redistribution of best frequencies (BFs) across auditory cortex in our control mice, consistent with prior work. By contrast,Dbh−/−mice failed to exhibit the expected redistribution of BFs, even though NE-deficient and NE-competent mice showed comparable auditory cortical organization when reared in a quiet colony environment. These data suggest that while intrinsic tonotopic patterning of auditory cortical circuitry occurs independently from NE, NE is required for critical period plasticity in auditory cortex.
Revisiting the Evidence for Collapsing Boundaries and Urgency Signals in Perceptual Decision-Making
Authors: Hawkins Guy E. , Forstmann Birte U. , Wagenmakers Eric-Jan , Ratcliff Roger , Brown Scott D.
Published: February 2015

For nearly 50 years, the dominant account of decision-making holds that noisy information is accumulated until a fixed threshold is crossed. This account has been tested extensively against behavioral and neurophysiological data for decisions about consumer goods, perceptual stimuli, eyewitness testimony, memories, and dozens of other paradigms, with no systematic misfit between model and data. Recently, the standard model has been challenged by alternative accounts that assume that less evidence is required to trigger a decision as time passes. Such “collapsing boundaries” or “urgency signals” have gained popularity in some theoretical accounts of neurophysiology. Nevertheless, evidence in favor of these models is mixed, with support coming from only a narrow range of decision paradigms compared with a long history of support from dozens of paradigms for the standard theory. We conducted the first large-scale analysis of data from humans and nonhuman primates across three distinct paradigms using powerful model-selection methods to compare evidence for fixed versus collapsing bounds. Overall, we identified evidence in favor of the standard model with fixed decision boundaries. We further found that evidence for static or dynamic response boundaries may depend on specific paradigms or procedures, such as the extent of task practice. We conclude that the difficulty of selecting between collapsing and fixed bounds models has received insufficient attention in previous research, calling into question some previous results.
Control of Axon Guidance and Neurotransmitter Phenotype of dB1 Hindbrain Interneurons by Lim-HD Code
Authors: Kohl Ayelet , Marquardt Till , Klar Avihu , Sela-Donenfeld Dalit
Published: February 2015

Hindbrain dorsal interneurons (HDIs) are implicated in receiving, processing, integrating, and transmitting sensory inputs from the periphery and spinal cord, including the vestibular, auditory, and proprioceptive systems. During development, multiple molecularly defined HDI types are set in columns along the dorsoventral axis, before migrating along well-defined trajectories to generate various brainstem nuclei. Major brainstem functions rely on the precise assembly of different interneuron groups and higher brain domains into common circuitries. Yet, knowledge regarding interneuron axonal patterns, synaptic targets, and the transcriptional control that govern their connectivity is sparse. The dB1 class of HDIs is formed in a district dorsomedial position along the hindbrain and gives rise to the inferior olive nuclei, dorsal cochlear nuclei, and vestibular nuclei. dB1 interneurons express various transcription factors (TFs): the pancreatic transcription factor 1a (Ptf1a), the homeobox TF-Lbx1 and the Lim-homeodomain (Lim-HD), and TF Lhx1 and Lhx5. To decipher the axonal and synaptic connectivity of dB1 cells, we have used advanced enhancer tools combined with conditional expression systems and the PiggyBac-mediated DNA transposition system in avian embryos. Multiple ipsilateral and contralateral axonal projections were identified ascending toward higher brain centers, where they formed synapses in the Purkinje cerebellar layer as well as at discrete midbrain auditory and vestibular centers. Decoding the mechanisms that instruct dB1 circuit formation revealed a fundamental role for Lim-HD proteins in regulating their axonal patterns, synaptic targets, and neurotransmitter choice. Together, this study provides new insights into the assembly and heterogeneity of HDIs connectivity and its establishment through the central action of Lim-HD governed programs.
Dysregulation of Glutamine Transporter SNAT1 in Rett Syndrome Microglia: A Mechanism for Mitochondrial Dysfunction and Neurotoxicity
Authors: Jin Lee-Way , Horiuchi Makoto , Wulff Heike , Liu Xiao-Bo , Cortopassi Gino A. , Erickson Jeffrey D. , Maezawa Izumi
Published: February 2015

Rett syndrome (RTT) is an autism spectrum disorder caused by loss-of-function mutations in the gene encoding MeCP2, an epigenetic modulator that binds the methyl CpG dinucleotide in target genes to regulate transcription. Previously, we and others reported a role of microglia in the pathophysiology of RTT. To understand the mechanism of microglia dysfunction in RTT, we identified a MeCP2 target gene,SLC38A1, which encodes a major glutamine transporter (SNAT1), and characterized its role in microglia. We found that MeCP2 acts as a microglia-specific transcriptional repressor ofSNAT1. Because glutamine is mainly metabolized in the mitochondria, where it is used as an energy substrate and a precursor for glutamate production, we hypothesize that SNAT1 overexpression in MeCP2-deficient microglia would impair the glutamine homeostasis, resulting in mitochondrial dysfunction as well as microglial neurotoxicity because of glutamate overproduction. Supporting this hypothesis, we found that MeCP2 downregulation or SNAT1 overexpression in microglia resulted in (1) glutamine-dependent decrease in microglial viability, which was corroborated by reduced microglia counts in the brains of MECP2 knock-out mice; (2) proliferation of mitochondria and enhanced mitochondrial production of reactive oxygen species; (3) increased oxygen consumption but decreased ATP production (an energy-wasting state); and (4) overproduction of glutamate that caused NMDA receptor-dependent neurotoxicity. The abnormalities could be rectified by mitochondria-targeted expression of catalase and a mitochondria-targeted peptide antioxidant, Szeto-Schiller 31. Our results reveal a novel mechanism via which MeCP2 regulates bioenergetic pathways in microglia and suggest a therapeutic potential of mitochondria-targeted antioxidants for RTT.
Differential Magnetic Resonance Neurofeedback Modulations across Extrinsic (Visual) and Intrinsic (Default-Mode) Nodes of the Human Cortex
Authors: Harmelech Tal , Friedman Doron , Malach Rafael
Published: February 2015

Previous advances in magnetic resonance imaging allow the analysis of blood oxygen level-dependent signals in real time, thus opening the possibility of feeding an index of these signals back to scanned human participants. However, it is still not known to what extent different cortical networks may differ in their sensitivity to such internally generated neurofeedback (NF). Here, we compare NF efficacy across six cortical regions including: early and high-order visual areas and the posterior parietal lobe, a prominent node of the default mode network (DMN). Our results reveal a consistent difference in NF activation across these areas. Sham controls ruled out a role of attention/arousal in these effects. These differences are suggestive of a relationship to the relative reliance on intrinsic information, moving from early visual cortex (lowest) to the DMN (highest). Interestingly, the visual parahippocampal place area showed NF activation closer to the DMN node. The results are compatible with the notion of the DMN as an intrinsically oriented system.
Inspiration Is the Major Regulator of Human CSF Flow
Authors: Dreha-Kulaczewski Steffi , Joseph Arun A. , Merboldt Klaus-Dietmar , Ludwig Hans-Christoph , Gärtner Jutta , Frahm Jens
Published: February 2015

The mechanisms behind CSF flow in humans are still not fully known. CSF circulates from its primary production sites at the choroid plexus through the brain ventricles to reach the outer surface of the brain in the subarachnoid spaces from where it drains into venous bloodstream and cervical lymphatics. According to a recent concept of brain fluid transport, established in rodents, CSF from the brain surface also enters the brain tissue along para-arterial routes and exits through paravenous spaces again into subarachnoid compartments. This unidirectional flow is mainly driven by arterial pulsation. To investigate how CSF flow is regulated in humans, we applied a novel real-time magnetic resonance imaging technique at high spatial (0.75 mm) and temporal (50 ms) resolution in healthy human subjects. We observed significant CSF flow exclusively with inspiration. In particular, during forced breathing, high CSF flow was elicited during every inspiration, whereas breath holding suppressed it. Only a minor flow component could be ascribed to cardiac pulsation. The present results unambiguously identify inspiration as the most important driving force for CSF flow in humans. Inspiratory thoracic pressure reduction is expected to directly modulate the hydrostatic pressure conditions for the low-resistance paravenous, venous, and lymphatic clearance routes of CSF. Furthermore, the experimental approach opens new clinical opportunities to study the pathophysiology of various forms of hydrocephalus and to design therapeutic strategies in relation to CSF flow alterations.
PKC Enhances the Capacity for Secretion by Rapidly Recruiting Covert Voltage-Gated Ca2+Channels to the Membrane
Authors: Groten Christopher J. , Magoski Neil S.
Published: February 2015

It is unknown whether neurons can dynamically control the capacity for secretion by promptly changing the number of plasma membrane voltage-gated Ca2+channels. To address this, we studied peptide release from the bag cell neurons ofAplysia californica, which initiate reproduction by secreting hormone during an afterdischarge. This burst engages protein kinase C (PKC) to trigger the insertion of a covert Ca2+channel, Apl Cav2, alongside a basal channel, Apl Cav1. The significance of Apl Cav2 recruitment to secretion remains undetermined; therefore, we used capacitance tracking to assay secretion, along with Ca2+imaging and Ca2+current measurements, from cultured bag cell neurons under whole-cell voltage-clamp. Activating PKC with the phorbol ester, PMA, enhanced Ca2+entry, and potentiated stimulus-evoked secretion. This relied on channel insertion, as it was occluded by preventing Apl Cav2 engagement with prior whole-cell dialysis or the cytoskeletal toxin, latrunculin B. Channel insertion reduced the stimulus duration and/or frequency required to initiate secretion and strengthened excitation-secretion coupling, indicating that Apl Cav2 accesses peptide release more readily than Apl Cav1. The coupling of Apl Cav2 to secretion also changed with behavioral state, as Apl Cav2 failed to evoke secretion in silent neurons from reproductively inactive animals. Finally, PKC also acted secondarily to enhance prolonged exocytosis triggered by mitochondrial Ca2+release. Collectively, our results suggest that bag cell neurons dynamically elevate Ca2+channel abundance in the membrane to ensure adequate secretion during the afterdischarge.
Prospective Coding of Dorsal Raphe Reward Signals by the Orbitofrontal Cortex
Authors: Zhou Jingfeng , Jia Chunying , Feng Qiru , Bao Junhong , Luo Minmin
Published: February 2015

The orbitofrontal cortex (OFC) is important for the cognitive processes of learning and decision making. Previous recordings have revealed that OFC neurons encode predictions of reward outcomes. The OFC is interconnected with the dorsal raphe nucleus (DRN), which is a major serotonin (5-HT) center of the brain. Recent studies have provided increasing evidence that the DRN encodes reward signals. However, it remains unclear how the activity of DRN neurons affects the prospective reward coding of OFC neurons. By combining single-unit recordings from the OFC and optogenetic activation of the DRN in behaving mice, we found that DRN stimulation is sufficient to organize and modulate the anticipatory responses of OFC neurons. During pavlovian conditioning tasks for mice, odorant cues were associated with the delayed delivery of natural rewards of sucrose solution or DRN stimulation. After training, OFC neurons exhibited prospective responses to the sucrose solution. More importantly, the coupling of an odorant with delayed DRN stimulation resulted in tonic excitation or inhibition of OFC neurons during the delay period. The intensity of the prospective responses was affected by the frequency and duration of DRN stimulation. Additionally, DRN stimulation bidirectionally modulated the prospective responses to natural rewards. These experiments indicate that signals from the DRN are incorporated into the brain reward system to shape the cortical prospective coding of rewards.
α2-Chimaerin Is Required for Eph Receptor-Class-Specific Spinal Motor Axon Guidance and Coordinate Activation of Antagonistic Muscles
Authors: Kao Tzu-Jen , Nicholl Georgina C.B. , Johansen Jamie A. , Kania Artur , Beg Asim A.
Published: February 2015

Axonal guidance involves extrinsic molecular cues that bind growth cone receptors and signal to the cytoskeleton through divergent pathways. Some signaling intermediates are deployed downstream of molecularly distinct axon guidance receptor families, but the scope of this overlap is unclear, as is the impact of embryonic axon guidance fidelity on adult nervous system function. Here, we demonstrate that the Rho-GTPase-activating protein α2-chimaerin is specifically required for EphA and not EphB receptor signaling in mouse and chick spinal motor axons. Reflecting this specificity, the loss of α2-chimaerin function disrupts the limb trajectory of extensor-muscle-innervating motor axons the guidance of which depends on EphA signaling. These embryonic defects affect coordinated contraction of antagonistic flexor-extensor muscles in the adult, indicating that accurate embryonic motor axon guidance is critical for optimal neuromuscular function. Together, our observations provide the first functional evidence of an Eph receptor-class-specific intracellular signaling protein that is required for appropriate neuromuscular connectivity.
Phosphorylation of Synaptic Vesicle Protein 2A at Thr84 by Casein Kinase 1 Family Kinases Controls the Specific Retrieval of Synaptotagmin-1
Authors: Zhang Ning , Gordon Sarah L. , Fritsch Maximilian J. , Esoof Noor , Campbell David G. , Gourlay Robert , Velupillai Srikannathasan , Macartney Thomas , Peggie Mark , van Aalten Daan M.F. , Cousin Michael A. , Alessi Dario R.
Published: February 2015

Synaptic vesicle protein 2A (SV2A) is a ubiquitous component of synaptic vesicles (SVs). It has roles in both SV trafficking and neurotransmitter release. We demonstrate that Casein kinase 1 family members, including isoforms of Tau–tubulin protein kinases (TTBK1 and TTBK2), phosphorylate human SV2A at two constellations of residues, namely Cluster-1 (Ser42, Ser45, and Ser47) and Cluster-2 (Ser80, Ser81, and Thr84). These residues are also phosphorylatedin vivo, and the phosphorylation of Thr84 within Cluster-2 is essential for triggering binding to the C2B domain of human synaptotagmin-1. We show by crystallographic and other analyses that the phosphorylated Thr84 residue binds to a pocket formed by three conserved Lys residues (Lys314, Lys326, and Lys328) on the surface of the synaptotagmin-1 C2B domain. Finally, we observed dysfunctional synaptotagmin-1 retrieval during SV endocytosis by ablating its phospho-dependent interaction with SV2A, knockdown of SV2A, or rescue with a phosphorylation-null Thr84 SV2A mutant in primary cultures of mouse neurons. This study reveals fundamental details of how phosphorylation of Thr84 on SV2A controls its interaction with synaptotagmin-1 and implicates SV2A as a phospho-dependent chaperone required for the specific retrieval of synaptotagmin-1 during SV endocytosis.
Spillover Transmission Is Mediated by the Excitatory GABA Receptor LGC-35 inC. elegans
Authors: Jobson Meghan A. , Valdez Chris M. , Gardner Jann , Garcia L. Rene , Jorgensen Erik M. , Beg Asim A.
Published: February 2015

Under most circumstances, GABA activates chloride-selective channels and thereby inhibits neuronal activity. Here, we identify a GABA receptor in the nematodeCaenorhabditis elegansthat conducts cations and is therefore excitatory. Expression inXenopusoocytes demonstrates that LGC-35 is a homopentameric cation-selective receptor of the cys-loop family exclusively activated by GABA. Phylogenetic analysis suggests that LGC-35 evolved from GABA-A receptors, but the pore-forming domain contains novel molecular determinants that confer cation selectivity. LGC-35 is expressed in muscles and directly mediates sphincter muscle contraction in the defecation cycle in hermaphrodites, and spicule eversion during mating in the male. In the locomotory circuit, GABA release directly activates chloride channels on the muscle to cause muscle relaxation. However, GABA spillover at these synapses activates LGC-35 on acetylcholine motor neurons, which in turn cause muscles to contract, presumably to drive wave propagation along the body. These studies demonstrate that both direct and indirect excitatory GABA signaling plays important roles in regulating neuronal circuit function and behavior inC. elegans.
A genetic variant of MDM4 influences regulation by multiple microRNAs in prostate cancer
Authors: Stegeman Shane , Moya Leire , Selth Luke A , Spurdle Amanda B , Clements Judith A , Batra Jyotsna
Published: February 2015

The oncogeneMDM4, also known asMDMXorHDMX, contributes to cancer susceptibility and progression through its capacity to negatively regulate a range of genes with tumour-suppressive functions. As part of a recent genome-wide association study it was determined that the A-allele of the rs4245739 SNP (A>C), located in the 3′-UTR ofMDM4, is associated with an increased risk of prostate cancer. Computational predictions revealed that the rs4245739 SNP is located within a predicted binding site for three microRNAs (miRNAs): miR-191-5p, miR-887 and miR-3669. Herein, we show using reporter gene assays and endogenous MDM4 expression analyses that miR-191-5p and miR-887 have a specific affinity for the rs4245739 SNP C-allele in prostate cancer. These miRNAs do not affectMDM4mRNA levels, rather they inhibit its translation in C-allele-containing PC3 cells but not in LNCaP cells homozygous for the A-allele. By analysing gene expression datasets from patient cohorts, we found that MDM4 is associated with metastasis and prostate cancer progression and that targeting this gene with miR-191-5p or miR-887 decreases in PC3 cell viability. This study is the first, to our knowledge, to demonstrate regulation of theMDM4rs4245739 SNP C-allele by two miRNAs in prostate cancer, and thereby to identify a mechanism by which theMDM4rs4245739 SNP A-allele may be associated with an increased risk for prostate cancer.
Improvement of chemotherapeutic drug efficacy by endoplasmic reticulum stress
Authors: Mihailidou Chrysovalantou , Chatzistamou Ioulia , Papavassiliou Athanasios G , Kiaris Hippokratis
Published: February 2015

Tunicamycin (TUN), an inhibitor of protein glycosylation and therefore a potent stimulator of endoplasmic reticulum (ER) stress, has been used to improve anticancer drug efficacy, but the underlying mechanism remains obscure. In this study, we show that acute administration of TUN in mice induces the unfolded protein response and suppresses the levels of P21, a cell cycle regulator with anti-apoptotic activity. The inhibition of P21 after ER stress appears to be C/EBP homologous protein (CHOP)-dependent because in CHOP-deficient mice, TUN not only failed to suppress, but rather induced the expression of P21. Results of promoter-activity reporter assays using human cancer cells and mouse fibroblasts indicated that the regulation of P21 by CHOP operates at the level of transcription and involves direct binding of CHOP transcription factor to the P21 promoter. The results of cell viability and clonogenic assays indicate that ER-stress-related suppression of P21 expression potentiates caspase activation and sensitizes cells to doxorubicin treatment, while administration of TUN to mice increases the therapeutic efficacy of anticancer therapy for HepG2 liver and A549 lung cancers.
Comparative Study on the Pulmonary Toxicity of Indium Hydroxide, Indium-Tin Oxide, and Indium Oxide Following Intratracheal Instillations into the Lungs of Rats
Authors: Tanaka Akiyo , Hirata Miyuki , Matsumura Nagisa , Koga Kazunori , Shiratani Masaharu , Kiyohara Yutaka
Published: February 2015

We studied the pulmonary toxicity of indium hydroxide (In(OH)3), which is produced during a recycling process of indium-tin oxide (ITO), in comparison with that of ITO or indium oxide (In2O3), two raw materials of flat panel displays. One hundred and forty-four male Wistar rats were intratracheally given equivalent doses of 10 mg/kg indium as In(OH)3, ITO, or In2O3 particles, twice a week, for a total of 5 times for 2 weeks. Control rats were given distilled water as a vehicle. After 3 weeks, these rats were serially euthanized, and toxicological effects were determined. Body weight gain was significantly suppressed in the In(OH)3-treated rats compared to that in the control group, but not in the ITO- or In2O3-treated rats. Relative lung weights in all the indium-treated groups significantly increased compared to those in the control group throughout the observation period. Furthermore, lung weights in the In(OH)3 group were significantly higher than those in either the ITO or In2O3 group. Blood indium levels in the In(OH)3-treated rats were much higher, 70- to 200-fold, than those in the In2O3- or ITO-treated rats at each time point. Although the lung indium content decreased gradually during the observation periods, the content in the In(OH)3 group was significantly higher than that in either the ITO or In2O3 group. A histopathological analysis revealed foci indicating a slight to severe pulmonary inflammatory response, including exudation to alveolar spaces, were present in all the indium-treated groups. Interstitial fibrotic proliferation was seen only in the In(OH)3-treated rats. The severity of these lesions in the In(OH)3-treated rats was greater than that in either the ITO- or In2O3-treated rats.

The results of our study clearly demonstrated that In(OH)3 particles caused severe pulmonary toxicity when repeated intratracheal instillations were performed in rats. Furthermore, the toxic potency of In(OH)3 in the lung was much higher than that of ITO and In2O3. Accordingly, the toxicity of In(OH)3 particles should be considered in addition to that of ITO and In2O3 particles when indium exposure occurs.
Mixed-Ionic-Electronic-Conduction (MIEC)-Based Access Devices for 3D Multilayer Crosspoint Memory
Authors: Virwani Kumar , Burr Geoffrey W. , Narayanan Pritish , Kurdi Bülent
Published: February 2015

A number of applications call for the organization of resistive non-volatile memory (NVM) into large, densely-packed crossbar arrays. While resistive-NVM devices often possess some degree of inherent nonlinearity (typically 3-30× contrast), the operation of large (>1000×1000 device) arrays at low power tends to require large (> 1e7) ON-to-OFF ratios between the currents passed at high and at low voltages. Such large nonlinearities can be implemented by including a distinct access device together with each of the state-bearing resistive-NVM elements. While such an access device need not store data, its list of requirements is almost as challenging as the specifications demanded of the memory device.

We review our work on high-performance access devices based on Cu-containing Mixed-Ionic-Electronic Conduction (MIEC) materials [1–7]. (This version focuses only on the MIEC-based access device itself; previously-published longer versions of this work [8–10] also include more extensive surveys of competing devices as well.) These devices require only the low processing temperatures of the Back-End-Of-the-Line (BEOL), making them highly suitable for implementing multi-layer crossbar arrays. MIEC-based access devices offer large ON/OFF ratios (>1e7), a significant voltage margin Vm (over which current < 10nA), and ultra-low leakage (<10pA), while also offering the high current densities needed for PCM and the fully bipolar operation needed for high-performance RRAM. Scalability to critical dimensions (CD) <30nm and thicknesses <15nm, tight distributions and 100% yield in large (512kBit) arrays, long-term stability of the ultra-low leakage states, and sub-50ns turn-ON times have all been demonstrated. Numerical modeling of these MIEC-based access devices shows that their operation depends on Cu+ mediated hole conduction. Circuit simulations reveal that while scaled MIEC devices are suitable for large crossbar arrays of resistive-NVM devices with low (<1.2V) switching voltages, a compact vertical stack of two MIEC devices in series could support large crossbar arrays for switching voltages up to 2.5V.
What Controls Temperature Dependence of Yield Stress in L12-Ordered Intermetallic Compounds?
Authors: Inui Haruyuki , Okamoto Norihiko L.
Published: February 2015

The temperature dependence of yield stress and the associated dislocation dissociation in L12 intermetallic compounds are investigated in order to check the feasibility of the classification of L12 intermetallic compounds so far made in terms of the planarity of core structures of partial dislocations with b = 1/2<110> and 1/3<112> on {111} and {001} glide planes. In contrast to what is believed from the classification, the motion of APB-coupled dislocations is evidenced to give rise to the rapid decrease in yield stress at low temperatures for Pt3Al. In view of the fact that rapid decrease in yield stress at low temperatures is also observed in Co3(Al,W) and Co3Ti in which APB-coupled dislocations are responsible for deformation, the SISF-type dissociation is not a prerequisite for the rapidly decreasing CRSS for slip on (111) and the relative magnitudes of the APB energy on (111) and the SISF energy on (111) cannot be a primary factor that determines the type of the temperature dependence of CRSS for L12 compounds. The importance of the CSF energy as a factor determining the type of the temperature dependence of yield stress for L12 compounds through the changes in the planarity of the core structure of the APB-coupled partial dislocation with bp = ½[1$\overline 1$0] is discussed in the light of experimental evidence obtained from Pt3Al.
Thermal, Mechanical and Magneto-Mechanical Characterization of Liquid Crystalline Elastomers Loaded with Iron Oxide Nanoparticles
Authors: Herrera-Posada Stephany , Calcagno Barbara O. , Acevedo Aldo
Published: February 2015

Liquid crystalline elastomers (LCEs) are materials that reveal unusual mechanical, optical and thermal properties due to their molecular orientability characteristic of low molar mass liquid crystals while maintaining the mechanical elasticity distinctive of rubbers. As such, they are considered smart shape-changing responsive systems. In this work, we report on the preparation of magnetic sensitized nematic LCEs using iron oxide nanoparticles with loadings of up to 0.7 wt%. The resultant thermal and mechanical properties were characterized by differential scanning calorimetry, expansion/contraction experiments and extensional tests. The magnetic actuation ability was also evaluated for the neat elastomer and the composite with 0.5 wt% magnetic content, finding reversible contractions of up to 23% with the application of alternating magnetic fields (AMFs) of up to 48 kA/m at 300 kHz. Thus, we were able to demonstrate that the inclusion of magnetic nanoparticles yields LCEs with adjustable properties that can be tailored by changing the amount of particles embedded in the elastomeric matrix, which can be suitable for applications in actuation, sensing, or as smart substrates.
Synthesis of Nanoporous Rutile Nanocrystals under Mild Conditions
Authors: Sabyrov Kairat , Yuwono Virany M. , Penn R. Lee
Published: February 2015

Single-crystalline rutile with porous and complex structure can be produced by tuning reaction conditions so as to maintain low titania solubility. X-ray diffraction, high-resolution transmission electron microscopy, and cryogenic transmission electron microscopy results are consistent with the hypothesis that oriented aggregation of anatase crystals precedes rutile nucleation and growth from anatase nanocrystal interfaces. The product rutile retains morphological and microstructure features consistent with an aggregation-based phase transformation because coarsening, or monomer-by-monomer growth, is suppressed under these conditions of low titania solubility.
Crystallization of Ni–P Fabricated by Electroless Deposition: Microscopic Mechanism
Authors: Zhan Xun , Ernst Frank
Published: February 2015

We investigate the crystallization of amorphous Ni–P with near-eutectic composition, fabricated by electroless plating as a 10 µm thick continuous layer. Aiming to understand phase transformations that occur upon heating and, in particular, the microscopic mechanism of crystallization, we combine a variety of complimentary characterization techniques. DSC (differential scanning calorimetry) during isothermal heating reveals the crystallization kinetics. Conventional-, high-resolution-, and analytical TEM (transmission electron microscopy) and TEM-based electron diffraction provide high-spatial-resolution information on phase nucleation and spatial distribution of atom species, particularly the crystallography of the nucleating crystalline phases (Ni3P and Ni) and the spatial distribution of phosphorus in the partially and completely crystallized alloy. Our results indicate that crystallization proceeds by homogeneous nucleation of Ni3P grains. Internally, these exhibit a microstructure of radially oriented subgrains containing Ni nano-platelets in a specific crystallographic OR (orientation relationship) with Ni3P. However, the preferred Ni–Ni3P OR differs from those reported in the literature for similar material. Combining our observation on the structure and microstructure of partially and completely crystallized Ni–P with the observed crystallization kinetics provides a deeper understanding of the microscopic mechanism of crystallization.
Quantification of Oxidizer Systems for Porous Silicon Combustion
Authors: Abraham Ani , Piekiel Nicholas W. , Knick Cory R. , Morris Christopher J. , Dreizin Edward
Published: February 2015

We present the first quantitative assessment of combustion dynamics of on-chip porous silicon (PS) energetic material using sulfur and nitrate-based oxidizers with potential for improved moisture stability and/or minimized environmental impact compared to sodium perchlorate (NaClO4). Material properties of the PS films were characterized using gas adsorption porosimetry, and profilometry to calculate specific surface area, porosity and etch depth. The PS/sulfur energetic composite was formed using three pore loading techniques, where the combustion speeds ranged from 2.9 – 290 m/s. The nitrate-based oxidizers were solution-deposited using different compatible solvents, and depending on the metal-nitrate yielded combustion speeds of 3.1 – 21 m/s. Additionally, the combustion enthalpies from bomb calorimetry experiments are reported for the alternative PS/oxidizer systems in both nitrogen and oxygen environments.
Crystallography of Bcc/T1/T2 Three-Phase Microstructure in the Directionally Solidified Mo-Nb-Si-B Alloy
Authors: Takata Naoki , Sekido Nobuaki , Takeyama Masao , Perepezko John H.
Published: February 2015

In the present study, the crystallographic features of bcc/T1/T2 three-phase microstructure in a directionally solidified Mo–32.2Nb–19.5Si–4.7B (at.%) alloy have been examined by electron back-scattering diffraction (EBSD) analysis. The alloy was directionally solidified using an optical floating zone (OFZ) furnace in a flowing Ar gas atmosphere at a constant growth rate of 10 mm/hour. The microstructure of the directionally solidified alloy is characterized by an elongated T2 phase surrounded by inclusions of bcc and T1 phases with an interwoven morphology. The T2 grains are faceted on the (001) planes and elongated along the [110] direction. The T2 phase has an orientation relationship of (001)T2 // (011)bcc and [130]T2 // [2${\rm{\bar 1}}$1]bcc with the bcc phase, whereas any particular orientation relationships of T1 phase with bcc and T2 phases have not been found. These crystallographic features of bcc/T1/T2 three-phase microstructure suggest that the primary T2 phase crystallizes and grows along the [110] direction in liquid phase, followed by nucleation of the bcc phase on the interface between T2 and liquid phases, resulting in bcc/T1 two-phase eutectic reaction surrounding the elongated T2 phase.
Poly(n-butylcyanoacrylate) Nanoparticles as Carriers for Adenosine triphosphate
Authors: Wischke Christian , Weigel Judith , Lendlein Andreas
Published: February 2015

Adenosine triphosphate (ATP) has numerous biological functions both intra- and extracellularly, including effects on the directed migration of cells with a regenerative potential in brain tissue. Therefore, carrier systems would be of interest that would be capable to be loaded with ATP and release it in a controlled manner. In the present study, poly(n-butylcyanoacrylate) (PBCA) nanoparticles as a potential carrier system were prepared by anionic polymerization using different polymerization media, which resulted in different zeta potential values and in some cases aggregation of nanoparticles. By decorating the particle surface with positively charged diethylaminoethyl dextran, multivalent ionic interaction allowed to load ATP to the nanoparticles by adsorption. In release experiments, an ATP release over 6 hours was observed. ATP-loaded nanoparticles may thus be suitable to explore biological effects of short-term ATP delivery for biomedical applications.
Development of a Single Molecular Tunnel-Current Identification method For Electrical Genome Sequencing
Authors: Ohshiro Takahito , Tsutsui Makusu , Yokota Kazumichi , Kawai Tomoji , Taniguchi Masateru
Published: February 2015

We developed a tunnel-current based identification method by using nano-gap integrated devices. We performed electrical measurements for mono-nucleotide and oligo-nucleotide during its translocation of molecules between the nano-gap. Based on this determined electrical conductivity for single-nucleotides, we electrically identify the base-type in oligonucleotides, and found that this time-profiles represents the molecular translocation behaviors inside nano-gap. This method could be a promising for an electrical nucleotide sequencing methodology with label-free, high-speed, and low-cost.
Direct laser fabrication of nanostructures on Si(001)
Authors: Haghizadeh Anahita , Yang Haeyeon
Published: February 2015

We study how the period of transient thermal gradient impacts on morphologies of nanostructures on the Si(001) surface. Strain-free, self-assembled nanodots as well as periodic nanowires are fabricated directly on Si(001) surfaces by applying high power laser pulses on the surface interferentially. The morphologies of the nanostructures are studied by atomic force microscopy. Generally, the laser irradiated surfaces show nanowires but nanodots are also observed. The nanowire width increases with interference period. The narrowest nanowires observed have the width smaller than 50 nm, which is four times smaller than the interference period while the nanodots have a base width of 43 nm and height of 8 nm.
A Computational Study of the Effects of Charging Parameters on the Performance and Reversibility of a New Type SOFC Storage Battery
Authors: Jin Xinfang , Zhao Xuan , Huang Kevin
Published: February 2015

A high-fidelity two-dimensional axial symmetrical multi-physics model is established to analyze and predict the performance of a recently discovered solid oxide metal-air redox battery (SOMARB). In particular for this study, the effects of the parameters used in the charge cycle including current density, depth-of-discharge and kinetic rate of Fe3O4-reduction on the performance have been systematically investigated. Three strategies are subsequently developed with goal of achieving a balanced specific energy and cycle efficiency for the best performance of SOMARB.
Use of methods of cartographic representation and econometrics for defining the correlation between real estate prices and a distance to a city centre
Authors: Bitner Agnieszka , Nawrocki Piotr , Litwin Urszula
Published: February 2015

The article presents using methods of cartographic representation and econometrics and statistical description to defining the correlation between unit prices of an undeveloped land property
and a distance to a city centre. Sold undeveloped land located within administrative boundaries
of the city of Jasło have been the subject of the study.
The problem of horizontal refraction in setting out tunnel control networks
Authors: Bryś Henryk
Published: February 2015

The paper presents the problem of the influence of non-uniform horizontal refraction field of
the measurement environment on the results of determining the astronomical azimuths and
transferring the coordinates in the geodetic tunnel network. The concept of a modular network
alignment with simultaneous elimination of the effects of horizontal refraction is presented.
Automatic TOTAL STATION and the results of precise angles and distances measurements allow currently effective multi stage linear-angular networks adjustment during tunnelling. The
results of the innovative group tunnel networks adjustments are the coordinates of the network
points and the elimination of existing disruptions in the course of the sight line. The results
achieved so far for theoretical studies of horizontal refraction elimination and error ellipses
forecasts for long tunnel networks were presented.