Showing papers by "Jun Lu published in 2005"
TL;DR: A new, bead-based flow cytometric miRNA expression profiling method is used to present a systematic expression analysis of 217 mammalian miRNAs from 334 samples, including multiple human cancers, and finds the miRNA profiles are surprisingly informative, reflecting the developmental lineage and differentiation state of the tumours.
Abstract: Recent work has revealed the existence of a class of small non-coding RNA species, known as microRNAs (miRNAs), which have critical functions across various biological processes. Here we use a new, bead-based flow cytometric miRNA expression profiling method to present a systematic expression analysis of 217 mammalian miRNAs from 334 samples, including multiple human cancers. The miRNA profiles are surprisingly informative, reflecting the developmental lineage and differentiation state of the tumours. We observe a general downregulation of miRNAs in tumours compared with normal tissues. Furthermore, we were able to successfully classify poorly differentiated tumours using miRNA expression profiles, whereas messenger RNA profiles were highly inaccurate when applied to the same samples. These findings highlight the potential of miRNA profiling in cancer diagnosis.
9,470 citations
TL;DR: These findings explain how various drugs affect sleep and wakefulness, and provide the basis for a wide range of environmental influences to shape wake–sleep cycles into the optimal pattern for survival.
Abstract: A series of findings over the past decade has begun to identify the brain circuitry and neurotransmitters that regulate our daily cycles of sleep and wakefulness. The latter depends on a network of cell groups that activate the thalamus and the cerebral cortex. A key switch in the hypothalamus shuts off this arousal system during sleep. Other hypothalamic neurons stabilize the switch, and their absence results in inappropriate switching of behavioural states, such as occurs in narcolepsy. These findings explain how various drugs affect sleep and wakefulness, and provide the basis for a wide range of environmental influences to shape wake-sleep cycles into the optimal pattern for survival.
2,295 citations
TL;DR: In this article, a comparative analysis of the human, mouse, rat and dog genomes is presented to create a systematic catalogue of common regulatory motifs in promoters and 3' untranslated regions (3' UTRs).
Abstract: Comprehensive identification of all functional elements encoded in the human genome is a fundamental need in biomedical research. Here, we present a comparative analysis of the human, mouse, rat and dog genomes to create a systematic catalogue of common regulatory motifs in promoters and 3' untranslated regions (3' UTRs). The promoter analysis yields 174 candidate motifs, including most previously known transcription-factor binding sites and 105 new motifs. The 3'-UTR analysis yields 106 motifs likely to be involved in post-transcriptional regulation. Nearly one-half are associated with microRNAs (miRNAs), leading to the discovery of many new miRNA genes and their likely target genes. Our results suggest that previous estimates of the number of human miRNA genes were low, and that miRNAs regulate at least 20% of human genes. The overall results provide a systematic view of gene regulation in the human, which will be refined as additional mammalian genomes become available.
1,954 citations
TL;DR: This multistage processor provides the animal with flexibility so that environmental cues, such as food availability, ambient temperature and social interactions, can be integrated with the clock signal to sculpt an adaptive pattern of rhythmic daily activities that maximize the chances of survival and reproduction.
509 citations
TL;DR: It is demonstrated that α‐RIMs contain adjacent but separate Munc13‐ and Rab3‐binding sites, allowing formation of a tripartite Rab3/RIM/Munc13 complex, and suggested that the ternary Rab3–RIM–Munc 13 interaction approximates synaptic vesicles to the priming machinery, providing a substrate for presynaptic plasticity.
Abstract: α-RIMs and Munc13s are active zone proteins that control priming of synaptic vesicles to a readily releasable state, and interact with each other via their N-terminal sequences. The α-RIM N-terminal sequence also binds to Rab3s (small synaptic vesicle GTPases), an interaction that regulates presynaptic plasticity. We now demonstrate that α-RIMs contain adjacent but separate Munc13- and Rab3-binding sites, allowing formation of a tripartite Rab3/RIM/Munc13 complex. Munc13 binding is mediated by the α-RIM zinc-finger domain. Elucidation of the three-dimensional structure of this domain by NMR spectroscopy facilitated the design of a mutation that abolishes α-RIM/Munc13 binding. Selective disruption of this interaction in the calyx of Held synapse decreased the size of the readily releasable vesicle pool. Our data suggest that the ternary Rab3/RIM/Munc13 interaction approximates synaptic vesicles to the priming machinery, providing a substrate for presynaptic plasticity. The modular architecture of α-RIMs, with nested binding sites for Rab3 and other targets, may be a general feature of Rab effectors that share homology with the α-RIM N-terminal sequence.
256 citations
TL;DR: A large α-helical domain of mammalian Munc 13-1 that is autonomously folded and is sufficient to rescue the total arrest in neurotransmitter release observed in hippocampal neurons lacking Munc13s is identified.
Abstract: Munc13 proteins are essential in neurotransmitter release, controlling the priming of synaptic vesicles to a release-ready state. The sequences responsible for this priming activity are unknown. Here we identify a large α-helical domain of mammalian Munc13-1 that is autonomously folded and is sufficient to rescue the total arrest in neurotransmitter release observed in hippocampal neurons lacking Munc13s.
184 citations
TL;DR: Prussian blue nanotubes were fabricated by using a sequential deposition technique inside the 60-nm well-ordered pores of anodic alumina to tailor the length and the outer as well as the inner diameter of the tubes.
Abstract: Prussian blue nanotubes were fabricated by using a sequential deposition technique inside the 60-nm well-ordered pores of anodic alumina. By varying the deposition parameters and the dimensions of the template, we could tailor the length and the outer as well as the inner diameter of the tubes. The nanotubes were characterized using scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X-ray diffraction (XRD).
112 citations
TL;DR: In this article, the deformation microstructure of face-centered cubic cobalt subjected to surface mechanical attrition treatment was studied as a function of strain levels, and strain-induced gamma --> epsilon transformation and twinning deformation were evidenced by transmission electron microscopy and were found to progress continuously in ultrafine and nanocrystalline grains as the strain increased.
78 citations
TL;DR: In this article, HfO 2 films were grown by atomic layer deposition from Hf[N(CH 3 ) 2 ] 4 and H 2 O on Si(100) substrates in the temperature range of 205-400 °C.
72 citations
TL;DR: An efficient kinetic resolution of racemic Betti base with L-(+)-tartaric acid in acetone was developed based on a novel enantioselective N,O-deketalization, in excellent yields with a practically foolproof operation.
Abstract: An efficient kinetic resolution of racemic Betti base with L-(+)-tartaric acid in acetone was developed based on a novel enantioselective N,O-deketalization, by which the enantiopure R- and S-enantiomers of Betti base were obtained as the corresponding N,O-ketal compound and salt with L-(+)-tartaric acid, respectively, in excellent yields with a practically foolproof operation.
58 citations
TL;DR: In this paper, the carbon-silica composite films have been fabricated using sol-gel synthesis of silica-carbon precursor composites, followed by carbonization in an inert atmosphere.
Abstract: Carbon-silica composite films have been fabricated using sol-gel synthesis of silica-carbon precursor composites, followed by carbonization in an inert atmosphere. Four categories of samples were studied. These were the tetraethyl orthosilicate-only (TEOS-only), methyl trimethoxysilane (MTES), acetic acid anhydride (Ac2O) and soot (SOOT) samples. The carbon-silica films, spin-coated on aluminium and steel substrates, have been investigated for selective solar absorber functionality. Optical measurements were performed on these samples to determine solar absorptance and thermal emittance of each. The morphology of the films was studied by electron microscopy. Electron energy-loss spectroscopy (EELS) mapping was used to determine the carbon distribution. An optimum performance of 0.88 for solar absorptance and 0.41 for thermal emittance has been achieved. The sol-gel technique produced films with very flat surfaces and uniform thicknesses in the 1 μm range. The fine structure showed homogeneous mixing of the carbon and silica in the TEOS-only samples while the separate additions of MTES and Ac2O resulted in segregation of composition of the silica and carbon at nano-scale. The addition of 20 wt% MTES or 15 wt% Ac2O to the TEOS-only sols also helped to reduce the cracks in the TEOS-only samples. The addition of soot in place of the carbon precursor did not yield a net advantage.
TL;DR: In this article, high quality HfO2 films were deposited on p-type Si(100) wafers by an atomic layer deposition scheme, and the deposited films were smooth, amorphous, and stoichiometric, as determined by atomic force microscopy, x-ray diffraction, and xray photoelectron spectroscopy, respectively.
Abstract: High quality HfO2 films were deposited on p-type Si(100) wafers by an atomic layer deposition scheme The deposited films were smooth, amorphous, and stoichiometric, as determined by atomic force microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy, respectively The as-deposited films showed a very small interfacial layer between the HfO2 and silicon The index of refraction of the film was determined to be slightly smaller than that of bulk HfO2 by spectroscopic ellipsometry The films annealed in O2 and NH3 at 800°C showed a growth of the interfacial layer, which resembles a SiO2-rich dielectric layer Short-range order in the as-deposited films was determined to be monoclinic by the extended x-ray absorption fine structure measurements, and signs of crystallization were observed in the O2 annealed sample The films appeared to be polycrystalline upon high temperature (800°C) annealing as confirmed by high-resolution transmission electron microscopy Annealing in the forming gas (450°C)
TL;DR: In this paper, the lateral growth of Ni silicide towards the channel region of metal-oxide-semiconductor transistors (MOSFETs) fabricated on ultrathin silicon-on-insulator (SOI) wafers with a 20-nm-thick surface Si layer was characterized using electron microscopy.
Abstract: Lateral growth of Ni silicide towards the channel region of metal-oxide-semiconductor transistors (MOSFETs) fabricated on ultrathin silicon-on-insulator (SOI) is characterized using SOI wafers with a 20-nm-thick surface Si layer. With a 10-nm-thick Ni film for silicide formation, p-channel MOSFETs displaying ordinary device characteristics with silicided p+ source/drain regions were demonstrated. No lateral growth of NiSix under gate isolation spacers was found according to electron microscopy. When the Ni film was 20 nm thick, Schottky contact source/drain MOSFETs showing typical ambipolar characteristics were obtained. A severe lateral encroachment of NiSix into the channel region leading to an increased gate leakage was revealed, while no detectable voiding at the silicide front towards the Si channel was observed.
TL;DR: In this paper, high-resolution transmission electron microscopy and electron energy loss spectrometry were used to characterize the interfacial layer formed between the silicon substrate and the HfO 2 thin film grown by atomic layer deposition (ALD) from HfI 4 and O 2.
TL;DR: It is proposed that GABAA agonist anesthetics induce immobility at least in part by acting on these endogenous motor control pathways via the MPTA.
Abstract: Microinjection of pentobarbital and GABA(A)-receptor agonists into a brainstem region we have called the mesopontine tegmental anesthesia area (MPTA; Devor and Zalkind [2001] Pain 94:101-112) induces a general anesthesia-like state. As in systemic general anesthesia, rats show loss of the righting reflex, atonia, nonresponsiveness to noxious stimuli, and apparent loss of consciousness. GABA(A) agonist anesthetics acting on the MPTA might suppress movement by engaging endogenous motor regulatory systems previously identified in research on decerebrate rigidity and REM sleep atonia. Anterograde and retrograde tracing revealed that the MPTA has multiple descending projections to pontine and medullary areas known to be associated with motor control and atonia. Prominent among these are the dorsal pontine reticular formation and components of the rostral ventromedial medulla (RVM). The MPTA also has direct projections to the intermediate gray matter and ventral horn of the spinal cord via the lateral and anterior funiculi. These projections show a rostrocaudal topography: neurons in the rostral MPTA project to the RVM, but only minimally to the spinal cord, while those in the caudal MPTA project to both targets. Finally, the MPTA has ascending projections to motor control areas including the substantia nigra, subthalamic nucleus, and the caudate-putamen. Projections are bilateral with an ipsilateral predominance. We propose that GABA(A) agonist anesthetics induce immobility at least in part by acting on these endogenous motor control pathways via the MPTA. Analysis of MPTA connectivity has the potential for furthering our understanding of the neural circuitry responsible for the various functional components of general anesthesia.
TL;DR: In this article, the authors improved the growth rate and capacitance of HfO2 dielectric layers by depositing stacked structures with polycrystalline films of higher purity at 600 °C on thin HO2 sublayer grown on Si at 300 °C.
01 Aug 2005
TL;DR: An innovative and effective algorithm is proposed to estimate the spread-spectrum sequence of a direct spread-Spectrum sequence (DSSS) signal in non-cooperative communication systems using a measurement function and a detection statistic developed based on the idea of correlation.
Abstract: An innovative and effective algorithm is proposed to estimate the spread-spectrum sequence of a direct spread-spectrum sequence (DSSS) signal in non-cooperative communication systems. In particular, a measurement function, which is used for sequence synchronisation, and a detection statistic, which is for sequence estimation chip by chip, are developed based on the idea of correlation. Only linear complex addition and multiplication are required for the implementation of the algorithm. Theoretical analysis and computer simulations verify the effectiveness of the algorithm.
TL;DR: In this paper, the electrocatalytic activity of polyaniline and hydrogen molybdenum bronze electrodes for the oxidation of methanol, formaldehyde and formic acid in 0.5 M H 2 SO 4 solution was studied by using cyclic voltammetry between 0.2 and 0.8 V.
TL;DR: The structure shows that the RIM PDZ domain contains an unusually deep and narrow peptide-binding groove with an exquisite shape complementarity to the four ELKS C-terminal residues in their bound conformation, which determines, at least in part, their unique specificity.
TL;DR: Two H-shaped supramolecular complexes (C32H16N8Zn)2·(C12H12N2)·0.96H2O) and one T-shaped supersymmetric complex (C13H14N2 ) have been prepared from zinc(II) phthalocyanine with 1,2-bis(4-pyridyl)ethane (bipy-eta), 1, 2-di(4pyride)ethylene (dipyete) or 1,3-di (4
Abstract: Two H-shaped supramolecular complexes (C32H16N8Zn)2·(C12H12N2)·0.96H2O (1), (C32H16N8Zn)2·(C12H10N2)·(DMF)2
(2), and one T-shaped supramolecular complex C32H16N8Zn·C13H14N2
(3) have been prepared from zinc(II) phthalocyanine with 1,2-bis(4-pyridyl)ethane (bipy-eta), 1,2-di(4-pyridyl)ethylene (dipy-ete) or 1,3-di(4-pyridyl)propane (dipy-pra), respectively, and characterized by single-crystal X-ray diffraction, electronic absorption spectra and fluorescence spectra; the conformation of the bipyridines plays an important role in the assembly processes.
TL;DR: The phase formed in the 30-50 nm thick HfO2 films was monoclinic HfCl4 dominating over amorphous material without noticeable contribution from metastable crystallographic polymorphs as mentioned in this paper.
Abstract: HfO2 films were grown by atomic layer deposition from HfCl4 and H2O on atomic layer deposited 40-70 nm thick platinum, iridium, and ruthenium films in the temperature range 200-600°C. The phase formed in the 30-50 nm thick HfO2 films was monoclinic HfO2 dominating over amorphous material without noticeable contribution from metastable crystallographic polymorphs. The metal-dielectric-metal capacitor structures formed after evaporating Al gate electrodes demonstrated effective permittivity values in the range 11-16 and breakdown fields reaching 5 MV/cm. Iridium electrode films showed the highest stability in terms of reliability and reproducibility of dielectric characteristics.
TL;DR: In this article, the crystal structures of 1-5 have been determined by single-crystal X-ray diffraction and the crystal structure of (CBP)-(bipy) 5.
Abstract: 4,4'-(9-Fluorenylidene)diphenol (FDP) and/or 4,4'-cyclohexylidenebisphenol (CBP) is crystallized with bipyridine bases 4,4'-bipyridyl (bipy), 1,2-bis(4-pyridyl)ethane (bipy-eta), 1,2-di(4-pyridyl)ethylene (dipy-ete), and 4,4'-dipyridyl N,N'-dioxide (dipy-dox) to afford molecular complexes (FDP)-(bipy) 1, (FDP).(bipy-eta) 0.5 2, (FDP)2-(dipy-ete) 3, (FDP)-(dipy-dox) 4, and (CBP)-(bipy) 5. The crystal structures of 1-5 have been determined by single-crystal X-ray diffraction. All these molecular complexes exhibit polymeric supramolecular structures via O-H...N or O-H...O hydrogen-bonding. 1 forms double helices. 2 forms an infinite honeycomblike supramolecular structure. 3 forms a brick supramolecular structure. 4 forms an X-shaped supramolecular structure. 5 forms a single strand infinite helix. Thus, by changing the guest molecule, we can obtain different supramolecular hydrogen-bonded polymers through interactions of host-guest systems.
TL;DR: In this paper, the interfacial integrity of a gate stack featuring a polycrystalline SiGe gate, an ultrathin Al2O3/HfO2/Al 2O3 nano-laminate and a strained-SiGe surface-channel is examined for full transistor fabrication and characterization.
Abstract: The interfacial integrity of a gate stack featuring a polycrystalline SiGe gate, an ultrathin Al2O3/HfO2/Al2O3 nano-laminate and a strained-SiGe surface-channel is examined for full transistor fabrication and characterization. The high-κ dielectric nano-laminate is prepared by means of atomic layer deposition, and the SiGe channel and gate by chemical vapor deposition. After full transistor-processing including a rapid thermal processing step at 930 °C, the 3 nm thick HfO2 film becomes polycrystalline whereas the Al2O3 films about 0.5 nm thick remain in the amorphous state, according to analyses using high-resolution and energy-filtering transmission electron microscopy. No interfacial reaction is observable between the HfO2 film and the SiGe gate or channel, since both interfaces are flat and the two Al2O3 films remain continuous. Well-behaving gate leakage and capacitance characteristics of the transistors are found. An enhanced channel hole mobility compared to the Si universal curve is obtained.
TL;DR: In this paper, six new supramolecular structures have been obtained by bis(2-hydroxy-5-chlorophenyl) sulfide (HCS) and/or spirobicromane (SBC) with bipyridine bases 4,4'-bipyridyl (bipy), 1,2-di(4-pyrinearyl)ethylene (dipy-ete), 1-2-bis(4pyridymethylene)ethane, and 4, 4'-dipyrin
Abstract: Six new supramolecular structures have been prepared by bis(2-hydroxy-5-chlorophenyl) sulfide (HCS) and/or spirobicromane (SBC) with bipyridine bases 4,4'-bipyridyl (bipy), 1,2-di(4-pyridyl)ethylene (dipy-ete), 1,2-bis(4-pyridyl)ethane (bipy-eta), and 4,4'-dipyridyl N,N'-dioxide (dipy-dox). These molecular complexes are (HCS)-(bipy) 1, (HCS)-(dipy-ete) 2, (HCS)-(bipy-eta) 3, (HCS)-(dipy-dox) 4, (SBC)-(dipy-ete) 5, and (SBC).dipy-dox.H 2 O 6, respectively. The crystal structures of 1-6 have been determined by single crystal X-ray diffraction. All of these molecular complexes exhibit supramolecular structures via O-H...N or O-H...O hydrogen bondings. Both 1 and 2 form interestingly [2 + 2] macrocyclic structures, whose sizes are ca. 12.495(6) A x 5.087(6) A and 14.774(6) A x 5.300(6) A, respectively. Compounds 3 and 5 form one-dimensional zigzag chain structures. Compounds 4 and 6 form two-dimensional double helices. These results demonstrate that by changing the guest molecule, we can obtain different hydrogen-bonded supramolecular structures through different interactions.
TL;DR: Structural and magnetic properties of Al2O3/Ni81Fe19 thin films: from superparamagnetic nanoparticles ferromagnetic multilayers as discussed by the authors, which is a type of thin films.
Abstract: Structural and magnetic properties of Al2O3/Ni81Fe19 thin films: from superparamagnetic nanoparticles ferromagnetic multilayers
Journal Article•
TL;DR: A combined X-ray diffraction (XRD) and transmission electron microscopy (TEM) study has been carried out on copper films grown by atomic layer deposition at 400°C as discussed by the authors.