bluuebunny/crossref_metadata_2025_split huggingface dataset:
Criteria for the entanglement of composite systems with identical particles
Authors: Ghirardi G.C. , Marinatto L. 
Published: October 2004

AbstractWe identify a general criterion for detecting entanglement of pure bipartite quantum states describing a system of two identical particles. Such a criterion is basedbothon the consideration of the Slater‐Schmidt number of the fermionic and bosonic analog of the Schmidt decompositionandon the evaluation of the von Neumann entropy of the one‐particle reduced statistical operators.
Quantum information and general relativity
Authors: Peres A. 
Published: October 2004

AbstractThe Einstein‐Podolsky‐Rosen paradox (1935) is reexamined in the light of Shannon's information theory (1948). The EPR argument did not take into account that the observers' information was localized, like any other physical object. General relativity introduces new problems: there are horizons which act as on‐way membranes for the propagation of quantum information, in particular black holes which act like sinks.
Probabilistic programmable quantum processors
Authors: Bužek V. , Ziman M. , Hillery M. 
Published: October 2004

AbstractWe analyze how to improve performance of probabilistic programmable quantum processors. We show how the probability of success of the probabilistic processor can be enhanced by using the processor in loops. In addition, we show that an arbitrary SU(2) transformations of qubits can be encoded in program state of a universal programmable probabilistic quantum processor. The probability of success of this processor can be enhanced by a systematic correction of errors via conditional loops. Finally, we show that all our results can be generalized also for qudits.
Experimental realization of a single qubits purification protocol
Authors: Masullo L. , Ricci M. , De Martini F. 
Published: October 2004

AbstractWe report on the first experimental realization of the single qubits purification protocol [J. I. Cirac, A. K. Ekert, and C. Macchiavello, Phys. Rev. Lett. 82, 4344 (1999)] for two copies of a qubit sent through a depolarizing channel. The purification of the polarization‐encoded photonic qubits is achieved with passive linear optical elements. Our experimental results suggest that the present approach may represent a viable alternative to quantum error correction or entanglement distillation.
Optimal quantum machines by linear and non‐linear optics
Authors: Sciarrino F. , De Martini F. 
Published: October 2004

AbstractSince manipulations of qubits are constrained by the quantum mechanical rules, several classical information tasks can not be perfectly extended to the quantum world. The more relevant limitations in quantum information processing are the impossibility to perfectly clone any unknown qubit and to map it in its orthogonal state. Even if these two processes are unrealizable in their exact forms, they can be optimally approximated by the so‐called universal quantum machines: the optimal quantum cloning machine (UOQCM) and the universal‐NOT (U‐NOT) gate. Investigation of these optimal transformations is important since it reveals bounds on optimal manipulations of information with quantum systems. The 1−>1 U‐NOT gate and the 1−>2 UOQCM have been experimentally demonstrated by adopting the process of stimulated emission into an optical parametric amplifier and by slightly modifying the quantum state teleportation protocol.
Correlated imaging with macroscopic fields
Authors: Brambilla E. , Gatti A. , Bache M. , Lugiato L.A. 
Published: October 2004

AbstractWe demonstrate analytically that correlated imaging in the regime of large photon number can be implemented using both a classical and an entangled source. The classically correlated beams are obtained by dividing thermal radiation by a beam splitter while entangled beams are obtained through parametric down‐conversion. By treating the two system in parallel, a formal analogy is outlined between the two cases showing that classical beams can mimic qualitatively all the imaging features of the entangled beams. We also propose a method to improve substantially the imaging performances of correlated imaging which is based on homodyne detection combined with spatial averages.
Quantum entanglement and the uncertainty relations
Authors: Shih Y. 
Published: October 2004

AbstractEntangled EPR two‐particle system is characterized by Δ(p1+p2) = 0 and Δ (x1‐ x2) = 0, simultaneous. Even the momentum and position of each individual particle are completely undefined: Δ pj ∼ ∞, Δ xj ∼∞. This remarkable feature does not violate the uncertainty principle of quantum theory. It is the result of the surprising two‐particle quantum coherent superposition. Although questions regarding fundamental issues of quantum theory still exist, quantum entanglement has brought about a novel concept in nonlocal timing and positioning measurements with ultra‐high accuracy, even beyond the classical limit.
Generation of (2 × 2) and (4 × 4) two‐photon states with tunable degree of entanglement and mixedness
Authors: Barbieri M. , Cinelli C. , De Martini F. , Mataloni P. 
Published: October 2004

AbstractA parametric source of polarization entangled photon pairs with peculiar spatial characteristics allows to generate any kind of bi‐partite entangled states with tunable dgree of entanglement and mixedness. In particular, maximally entangled mixed states (MEMS) have been created in a reliable way by a “patchwork” technique and investigated by quantum tomography. By the same source, momentum‐polarization hyper‐entangled two‐photon states have been synthesized. The quality of the entanglement in the two degrees of freedom has been tested by multimode Hong‐Ou‐Mandel interferometry.
Entanglement assisted weak force detection
Authors: Fermani R. , Mancini S. , Tombesi P. 
Published: October 2004

AbstractWe study the role of entanglement in weak force detection. We consider massive probes, experiencing a weak force, monitored through optical meters which may be entangled. We reduce the problem of force detection to quantum binary decision. Entanglement is shown to be useful in such a kind of detection. The sensitivity limits are then discussed.
Radiation pressure and momentum in dielectrics
Authors: Loudon R. 
Published: October 2004

AbstractThe persistent conflicts in radiation pressure theory, concerning the signs of the surface forces on dielectrics and the momenta carried by single‐photon wavepackets in bulk media, are outlined. Measurements of the relevant quantities are reviewed and previous calculations are summarized and extended. Resolutions of the conflicts are proposed on the bases of the differing geometries of light beams and dielectric samples, and the partition of the momentum transfers between the components of coupled systems that separately carry the real and imaginary parts of the refractive index.
Quantum optics of single atoms
Authors: Walther H. 
Published: October 2004

AbstractThe widely discussed applications in quantum information and quantum cryptography require radiation sources capable of producing a fixed number of photons. This paper reviews the work performed in our laboratory using the one‐atom maser or micromaser to produce these fields on demand. In order to achieve this goal the maser is operating under the condition of the so‐called trapping states. In this situation the field of the micromaser stabilises to a photon number state. In the second part of the paper a single photon source on the basis of a trapped ion will be described. The strong localization and position control available when an ion trap is combined with an optical cavity is a big step forward in producing a deterministic atom‐field coupling necessary for quantum information processing.
Bose‐Einstein condensates as incubators of nonlinear and quantum optics
Authors: Arimondo E. 
Published: October 2004

AbstractThe equivalence between bosonic atoms and photons, and the large freedom in the manipulation of the atomic waves, has produced a large interest into the generation of atomic configurations with properties similar to those of the photon waves generated through nonlinear or quantum optics. Experiments performed on a rubidium Bose‐Einstein condensate within an optical lattice are analyzed within the framework of the connection between optics of photon and atom waves.
Atom interferometry in a vertical optical lattice
Authors: Modugno G. , de Mirandes E. , Ferlaino F. , Ott H. , Roati G. , Inguscio M. 
Published: October 2004

AbstractWe have studied the interference of degenerate quantum gases in a vertical optical lattice. The coherence of the atoms leads to an interference pattern when the atoms are released from the lattice. This has been shown for a Bose‐Einstein condensate in early experiments. Here we demonstrate that also for fermions an interference pattern can be observed provided that the momentum distribution is smaller than the recoil momentum of the lattice. Special attention is given to the role of interactions which wash out the interference pattern for a condensate trapped in the lattice but do not affect a spin polarized Fermi gas, where collisions at ultra cold temperatures are forbidden. Comparing the interference of the two quantum gases we find a clear superiority of fermions for trapped atom interferometry.
Generation of single photons and correlated photon pairs using InAs quantum dots
Authors: Santori C. , Fattal D. , Vuckovic J. , Solomon G.S. , Yamamoto Y. 
Published: October 2004

AbstractThis article reviews recent work on non‐classical light generation using semiconductor quantum dots. Experimental results for single‐photon generation are presented, including suppression of the two‐photon probability, coherence properties and two‐photon interference. An experiment demonstrating generation of polarization‐correlated photon pairs from biexciton recombination is also reviewed.
Automatic domain decomposition of proteins by a Gaussian Network Model
Authors: Kundu Sibsankar , Sorensen Dan C. , Phillips, George N. 
Published: October 2004

AbstractProteins are often comprised of domains of apparently independent folding units. These domains can be defined in various ways, but one useful definition divides the protein into substructures that seem to move more or less independently. The same methods that allow fairly accurate calculation of motion can be used to help classify these substructures. We show how the Gaussian Network Model (GNM), commonly used for determining motion, can also be adapted to automatically classify domains in proteins. Parallels between this physical network model and graph theory implementation are apparent. The method is applied to a nonredundant set of 55 proteins, and the results are compared to the visual assignments by crystallographers. Apart from decomposing proteins into structural domains, the algorithm can generally be applied to any large macromolecular system to decompose it into motionally decoupled sub‐systems. Proteins 2004. © 2004 Wiley‐Liss, Inc.
Potential determination of aminated pesticides and metabolites by cyclodextrin capillary electrophoresis–laser‐induced fluorescence using FITC as labelling
Authors: Navarrete‐Casas Miguel , Segura‐Carretero Antonio , Cruces‐Blanco Carmen , Fernández‐Gutiérrez Alberto 
Published: October 2004

AbstractWe describe a detailed study on the possibility of analyzing aminated pesticides and metabolites using pre‐column derivatization with fluorescein isothiocyanate (FITC) and their subsequent separation and detection by cyclodextrin capillary electrophoresis–laser‐induced fluorescence (CE‐LIF) detection. Different variables affecting the derivatization reaction (pH, FITC concentration, reaction time and temperature) and those related with the separation itself (buffer concentration, addition of various organic modifiers, pH, applied voltage and injection time) were studied. The limit of detection obtained was between 0.45 and 3.48 µg litre−1 showing a relative standard deviation between 0.26 and 2.08% at a concentration level of 50 µg litre−1. Copyright © 2004 Society of Chemical Industry
Identification of a chitinase‐producing bacterium C4 and histopathologic study on locusts
Authors: Tao Yong , Long Zhangfu , Xie Jing , Jin Hong , Ran Hongyan , Tao Ke , Ge Shaorong , Liu Kun , Liu Shigui 
Published: October 2004

AbstractIn order to develop the potential of chitinase‐producing micro‐organisms as biocontrol agents for insect pests, five chitinase‐producing bacterial strains (C1, C2, C3, C4 and C5) previously isolated from soil samples were chosen to infect grassland locusts. The data showed that the mortality rate of locusts fed with strain C4 was significantly higher than that of other groups, and its pathogenicity was confirmed by Koch's law. Midgut tissues of locusts infected with C4 were examined with a light microscope. Apparent histopathologic changes in midgut cells partly explained the pathogenesis of locusts. Therefore, strain C4 was considered to be a potential biocontrol agent. To determine the taxonomic position of C4, physiological and biochemical characteristics were determined and molecular identification was performed. The 16S rDNA gene of C4 was amplified, cloned and sequenced. Comparative sequence analysis demonstrated that C4 corresponded to the genera Sanguibacter, Oerskovia and Cellulomonas. On the basis of phenotypic characterization and sequence similarity analysis, strain C4 was more closely related to the genus Sanguibacter. This chitinase‐producing strain C4, which closely corresponds to the species of the genus Sanguibacter and is pathogenic to locusts, is here reported for the first time. Copyright © 2004 Society of Chemical Industry
Assessment of acetolactate synthase (ALS) tolerance to imazethapyr in red rice ecotypes (Oryza spp) and imidazolinone tolerant/ resistant rice (Oryza sativa) varieties
Authors: Avila Luis A , Lee Do‐Jin , Senseman Scott A , McCauley Garry N , Chandler James M , Cothren J Tom 
Published: October 2004

AbstractThree red rice ecotypes (Oryza spp), including LA 5, MS 5 and TX 4, were evaluated for acetolactate synthase resistance/tolerance to imazethapyr. The red rice ecotypes were compared with a tolerant line (CL‐121), a resistant line (CL‐161) and a conventional rice variety (Cypress). Based on enzymatic activity, the mean I50 values were 1.5, 1.1, 1.5, 1.6, 20.8 and 590.6 µM imazethapyr, respectively, for LA 5, MS 5, TX 4, Cypress, CL‐121 and CL‐161. CL‐161 was 32 times more resistant than CL‐121 and at least 420 times more resistant than the average of the red rice ecotypes and Cypress. Results from the acetolactate synthase (ALS) assay showed that red rice ecotypes and Cypress had high susceptibility to imazethapyr when compared with the tolerant CL‐121 and the resistant CL‐161. Measurable enzymatic tolerance to ALS‐inhibiting herbicides has not yet developed in these red rice ecotypes. Copyright © 2004 Society of Chemical Industry
Mobility of four triazole fungicides in two Indian soils
Authors: Singh Neera 
Published: October 2004

AbstractThe sorption and downward mobility of four triazole fungicides, triadimefon, hexaconazole, penconazole and propiconazole, were studied in two Indian soils (New Delhi and Punjab). Punjab soil (organic carbon 0.4%) showed greater sorption capability for triazole fungicides than New Delhi soil (organic carbon 0.5%) and the order of sorption of triazoles in both soils was: penconazole > hexaconazole > propiconazole > triadimefon. Fungicides were more mobile in New Delhi soil columns than Punjab soil columns, and increasing the total water flux from 1 pore volume to 3 pore volumes further increased the transport to lower down in the column. Triadimefon showed maximum mobility while penconazole was the least mobile triazole fungicide. After percolating 3 pore volumes of water, triadimefon leached down to 25–30 cm depth in New Delhi soil and 15–20 cm in Punjab soil columns. Downward mobility of triazole fungicides was in order of their sorption results. Copyright © 2004 Society of Chemical Industry
The use of essential oils to treat snoring
Authors: Prichard Andrew J. N. 
Published: October 2004

AbstractSnoring is a very common social inconvenience. This double‐blind study suggests a signiﬁcant reduction in snoring reported by bed partners in a group of snoring volunteers using either an essential oil spray or gargle formulation. Possible modes of action of the essential oils are discussed. Copyright © 2004 John Wiley & Sons, Ltd.
Effects of ganoderma lucidum on apoptotic and anti‐inﬂammatory function in HT‐29 human colonic carcinoma cells
Authors: Hong Kee‐jong , Dunn Dale M. , Shen Chwan‐Li , Pence Barbara C. 
Published: October 2004

AbstractLing Zhi extract (LZE) is a herbal mushroom preparation which been used world wide for the prevention and treatment of various cancers. The current study was designed to evaluate these claims in human colon cancer cells in terms of cancer preventive mechanisms. Results have demonstrated induction of apoptosis, anti‐inﬂammatory action and differential cytokine expression during induced inﬂammation in the human colonic carcinoma cell line, HT‐29. LZE caused no cytotoxicity in HT‐29 cells at doses less than 10 000 µg/ml. Increasing concentrations of LZE reduced prostaglandin E2 production, but increased nitric oxide production. LZE treatment induced apoptosis by increasing the activity of caspase‐3. RT‐PCR showed that LZE at a concentration of 5000 µg/ml decreased the expression of cyclooxygenase‐2 mRNA. Among 42 cytokines tested by protein array in this study, supplementation of LZE at doses of 500 and 5000 µg/ml to HT‐29 cells reduced the expression of interleukin‐8, macrophage inﬂammatory protein 1‐delta, vascular epithelial growth factor, and platelet‐derived growth factor. These results suggest that LZE has pro‐apoptotic and anti‐inﬂammatory functions, as well as inhibitory effects on cytokine expression during early inﬂammation in colonic carcinoma cells, which may be of signiﬁcance in the use of Chinese herbal alternative medicines for cancer prevention. Copyright © 2004 John Wiley & Sons, Ltd.
Herbal treatment following post‐seizure induction in rat by lithium pilocarpine: Scutellaria lateriﬂora (Skullcap), Gelsemium sempervirens (Gelsemium) and Datura stramonium (Jimson Weed) may prevent development of spontaneous seizures
Authors: Peredery Oksana , Persinger Michael A. 
Published: October 2004

AbstractAbout 1 week after the induction of status epilepticus in male rats by a single systemic injection of lithium (3 mEq/kg) and pilocarpine (30 g/kg), rats were continuously administered one of three herbal treatments through the water supply for 30 days. A fourth group received colloidal minerals and diluted food grade hydrogen peroxide in tap water, while a ﬁfth group of rats received only tap water (control). Herbal treatments were selected for their historical antiseizure activities and sedative actions on the nervous system. The numbers of spontaneous seizures per day during a 15 min observation interval were recorded for each rat during the treatment period and during an additional 30 days when only tap water was given. Rats that received a weak solution of the three herbal ﬂuid extracts of Scutellaria lateriﬂora (Skullcap), Gelsemium sempervirens (Gelsemium) and Datura stramonium (Jimson Weed) displayed no seizures during treatment while all the other groups were not seizure‐free. However, when this treatment was removed, the rats in this group displayed numbers of spontaneous seizures comparable to the controls. Although there is no proof that herbal remedies can control limbic or temporal lobe epilepsy, the results of this experiment strongly suggest that the appropriate combination of herbal compounds may be helpful as adjunctive interventions. Copyright © 2004 John Wiley & Sons, Ltd.
Neuroprotective effects of the antiparkinson drug Mucuna pruriens
Authors: Manyam Bala V. , Dhanasekaran Muralikrishnan , Hare Theodore A. 
Published: October 2004

AbstractMucuna pruriens possesses signiﬁcantly higher antiparkinson activity compared with levodopa in the 6‐hydroxydopamine (6‐OHDA) lesioned rat model of Parkinson's disease. The present study evaluated the neurorestorative effect of Mucuna pruriens cotyledon powder on the nigrostriatal tract of 6‐OHDA lesioned rats. Mucuna pruriens cotyledon powder signiﬁcantly increased the brain mitochondrial complex‐I activity but did not affect the total monoamine oxidase activity (in vitro). Unlike synthetic levodopa treatment, Mucuna pruriens cotyledon powder treatment signiﬁcantly restored the endogenous levodopa, dopamine, norepinephrine and serotonin content in the substantia nigra. Nicotine adenine dinucleotide (NADH) and coenzyme Q‐10, that are shown to have a therapeutic beneﬁt in Parkinson's disease, were present in the Mucuna pruriens cotyledon powder. Earlier studies showed that Mucuna pruriens treatment controls the symptoms of Parkinson's disease. This additional ﬁnding of a neurorestorative beneﬁt by Mucuna pruriens cotyledon powder on the degenerating dopaminergic neurons in the substantia nigra may be due to increased complex‐I activity and the presence of NADH and coenzyme Q‐10. Copyright © 2004 John Wiley & Sons, Ltd.
The chemical composition of some Lauraceae essential oils and their antifungal activities
Authors: Simić A. , Soković M. D. , Ristić M. , Grujić‐Jovanović S. , Vukojević J. , Marin P. D. 
Published: October 2004

AbstractThe antifungal activity of Aniba rosaeodora, Laurus nobilis, Sassafras albidum and Cinnamomum zeylanicum essential oils were investigated against 17 micromycetes. Among the tested fungal species were food poisoning, spoilage fungi, plant and animal pathogens. In order to determine fungistatic and fungicidal concentrations (MIC and MFC) macrodilution and microdilution tests were used. Linalool was the main component in the essential oil of A. rosaeodora, while 1.8‐cineole was dominant in L. nobilis. In sassafras essential oil safrole was the major component and in the oil of C. zeylanicum the main component was trans‐cinnamaldehyde. The essential oil of cinnamon showed the strongest antifungal activity. Copyright © 2004 John Wiley & Sons, Ltd.
Antiviral activities of medicinal herbs traditionally used in southern mainland China
Authors: Li Yaolan , Ooi Linda S. M. , Wang Hua , But Paul P. H. , Ooi Vincent E. C. 
Published: October 2004

AbstractThe aqueous extracts from 21 medicinal herbs traditionally used in southern mainland China were screened for antiviral activities against human herpes simplex virus type 1 (HSV‐1) and human respiratory syncytial virus (RSV) using a cytopathic effect (CPE) reduction assay. Three extracts from Agrimonia pilosa, Pithecellobium clypearia and Punica granatum, respectively, showed anti‐HSV‐1 activity, which was possibly contributed by the polyphenolic compounds in the herbal extracts. Six of the extracts, from Blumea laciniata, Elephantopus scaber, Laggera pterodonta, Mussaenda pubescens, Schefﬂera octophylla and Scutellaria indica, respectively, exhibited anti‐RSV activity with 50% inhibition (IC50) concentrations ranging from 12.5 to 32 µg/mL, and selective indices (SI) ranging from 11.2 to 40. In addition to polyphenolic compounds, other constituents present in these extracts may also contribute to their anti‐RSV activity. Copyright © 2004 John Wiley & Sons, Ltd.