bluuebunny/crossref_metadata_2025 huggingface dataset:
In Vitro
Selection of Highly Darunavir-Resistant and Replication-Competent HIV-1 Variants by Using a Mixture of Clinical HIV-1 Isolates Resistant to Multiple Conventional Protease Inhibitors
Authors: Koh Yasuhiro , Amano Masayuki , Towata Tomomi , Danish Matthew , Leshchenko-Yashchuk Sofiya , Das Debananda , Nakayama Maki , Tojo Yasushi , Ghosh Arun K. , Mitsuya Hiroaki
Published: September 2010

We attempted to select HIV-1 variants resistant to darunavir (DRV), which potently inhibits the enzymatic activity and dimerization of protease and has a high genetic barrier to HIV-1 development of resistance to DRV. We conducted selection using a mixture of 8 highly multi-protease inhibitor (PI)-resistant, DRV-susceptible clinical HIV-1 variants (HIV-1
MIX
) containing 9 to 14 PI resistance-associated amino acid substitutions in protease. HIV-1
MIX
became highly resistant to DRV, with a 50% effective concentration (EC
50
) ∼333-fold greater than that against HIV-1
NL4-3
. HIV-1
MIX
at passage 51 (HIV-1

MIX
P51

) replicated well in the presence of 5 μM DRV and contained 14 mutations. HIV-1

MIX
P51

was highly resistant to amprenavir, indinavir, nelfinavir, ritonavir, lopinavir, and atazanavir and moderately resistant to saquinavir and tipranavir. HIV-1

MIX
P51

had a resemblance with HIV-1
C
of the HIV-1
MIX
population, and selection using HIV-1
C
was also performed; however, its DRV resistance acquisition was substantially delayed. The H219Q and I223V substitutions in Gag, lacking in HIV-1

C
P51

, likely contributed to conferring a replication advantage on HIV-1

MIX
P51

by reducing intravirion cyclophilin A content. HIV-1

MIX
P51

apparently acquired the substitutions from another HIV-1 strain(s) of HIV-1
MIX
through possible homologous recombination. The present data suggest that the use of multiple drug-resistant HIV-1 isolates is of utility in selecting drug-resistant variants and that DRV would not easily permit HIV-1 to develop significant resistance; however, HIV-1 can develop high levels of DRV resistance when a variety of PI-resistant HIV-1 strains are generated, as seen in patients experiencing sequential PI failure, and ensuing homologous recombination takes place. HIV-1

MIX
P51

should be useful in elucidating the mechanisms of HIV-1 resistance to DRV and related agents.
Cytotoxicity of ORF3 Proteins from a Nonpathogenic and a Pathogenic Porcine Circovirus
Authors: Chaiyakul Mark , Hsu Karolynn , Dardari Rkia , Marshall Frank , Czub Markus
Published: September 2010

Porcine circovirus type 2 (PCV2) infection is associated with significant and serious swine diseases worldwide, while PCV1 appears to be a nonpathogenic virus. Previous studies demonstrated that the ORF3 protein of PCV2 (PCV2ORF3) was involved in PCV2 pathogenesis via its proapoptotic capability (J. Liu, I. Chen, Q. Du, H. Chua, and J. Kwang, J. Virol. 80:5065-5073, 2006). If PCV2ORF3-induced apoptosis is a determinant of virulence, PCV1ORF3 is hypothesized to lack this ability. The properties of PCV1 and PCV2 ORF3, expressed as fusion proteins to an enhanced green fluorescent protein (eGFP), were characterized with regard to their ability to cause cellular morphological changes, detachment, death, and apoptosis. PCV1ORF3 significantly induced more apoptotic cell death and was toxic to more different cell types than PCV2ORF3 was. PCV1ORF3-associated cell death was caspase dependent. PCV1ORF3 also induced poly(ADP-ribose) polymerase 1 (PARP) cleavage; however, whether PARP was involved in cell death requires further studies. Truncation of PCV1 and elongation of PCV2 ORF3 proteins revealed that the first 104 amino acids contain a domain capable of inducing cell death, whereas the C terminus of PCV1ORF3 contains a domain possibly responsible for enhancing cell death. These results suggest that the pathogenicity of PCV2 for pigs is either not determined or not solely determined by the ORF3 protein.
R&D IN CLEANER TECHNOLOGY AND INTERNATIONAL TRADE
Authors: BEN YOUSSEF SLIM
Published: September 2010

We consider a non-cooperative three-stage game played by two regulator-firm hierarchies. We suppose that raising public funds is socially costly and that market sizes are large enough. Contrary to what might be expected, we show that opening markets to international trade increases the per-unit emission-tax and decreases the per-unit R&D subsidy. It also increases the R&D level, production, and pollution when the marginal damage of pollution is sufficiently high, and, consequently, decreases the emission ratio and the social welfare. However, we think that these results might change if the market sizes are not too large or if we introduce asymmetric information.
AN INTEGER-VALUED BI-INVARIANT METRIC ON THE GROUP OF CONTACTOMORPHISMS OF ℝ2n × S1
Authors: SANDON SHEILA
Published: September 2010

In his article [23] on generating functions Viterbo constructed a bi-invariant metric on the group of compactly supported Hamiltonian symplectomorphisms of ℝ2n. Using the setup of [18] we extend the Viterbo metric to the group Cont0 c (ℝ2n×S1) of compactly supported contactomorphisms of ℝ2n×S1 isotopic to the identity. We also prove that Cont0 c(ℝ2n×S1) is unbounded with respect to this metric.
Finding one tight cycle
Authors: Cabello Sergio , Devos Matt , Erickson Jeff , Mohar Bojan
Published: September 2010

A cycle on a combinatorial surface is tight if it as short as possible in its (free) homotopy class. We describe an algorithm to compute a single tight, noncontractible, essentially simple cycle on a given orientable combinatorial surface inO(nlogn) time. The only method previously known for this problem was to compute the globally shortest noncontractible or nonseparating cycle inO(min{g3,n},nlogn) time, wheregis the genus of the surface. As a consequence, we can compute the shortest cycle freely homotopic to a chosen boundary cycle inO(nlogn) time, a tight octagonal decomposition inO(gnlogn) time, and a shortest contractible cycle enclosing a nonempty set of faces inO(nlog2n) time.
On the bichromatic
k
-set problem
Authors: Chan Timothy M.
Published: September 2010

We study a bichromatic version of the well-known
k-set problem
: given two sets
R
and
B
of points of total size
n
and an integer
k
, how many subsets of the form
(R
∩
h
) ∪ (
B
∖
h
) can have size exactly
k
over all halfspaces
h
? In the dual, the problem is asymptotically equivalent to determining the worst-case combinatorial complexity of the
k-level
in an arrangement of
n halfspaces
.

Disproving an earlier conjecture by Linhart [1993], we present the first nontrivial upper bound for all
k
≪
n
in two dimensions:
O
(
nk
1/3
+
n
5/6−ϵ
k
2/3+2 ϵ
+
k
2
) for any fixed ϵ<0. In three dimensions, we obtain the bound
O
(
nk
3/2
+
n
0.5034
k
2.4932
+
k
3
). Incidentally, this also implies a new upper bound for the original
k
-set problem in four dimensions:
O
(
n
2
k
3/2
+
n
1.5034
k
2.4932
+
n k
3
), which improves the best previous result for all
k
≪
n
0.923
. Extensions to other cases, such as arrangements of disks, are also discussed.
Nondecreasing paths in a weighted graph or
Authors: Williams Virginia Vassilevska
Published: September 2010

A travel booking office has timetables giving arrival and departure times for all scheduled trains, including their origins and destinations. A customer presents a starting station and demands a route with perhaps several train connections taking him to his destination as early as possible. The booking office must find the best route for its customers. This problem was first considered in the theory of algorithms by Minty [1958], who reduced it to a problem on directed edge-weighted graphs: find a path from a given source to a given target such that the consecutive weights on the path are nondecreasing and the last weight on the path is minimized. Minty gave the first algorithm for the single-source version of the problem, in which one finds minimum last weight nondecreasing paths from the source to every other vertex. In this article we give the first
linear
-time algorithm for this problem in the word-RAM model of computation. We also define an all-pairs version for the problem and give a strongly polynomial truly subcubic algorithm for it. Finally, we discuss an extension of the problem in which one also has prices on trip segments and one wishes to find a
cheapest
valid itinerary.
Hausdorff distance under translation for points and balls
Authors: Agarwal Pankaj K. , Har-Peled Sariel , Sharir Micha , Wang Yusu
Published: September 2010

We study the shape matching problem under the Hausdorff distance and its variants. In the first part of the article, we consider two sets
A,B
of balls in R
d
,
d
=2,3, and wish to find a translation
t
that minimizes the Hausdorff distance between
A+t
, the set of all balls in
A
shifted by
t
, and
B
. We consider several variants of this problem. First, we extend the notion of Hausdorff distance from sets of points to sets of balls, so that each ball has to be matched with the nearest ball in the other set. We also consider the problem in the standard setting, by computing the Hausdorff distance between the unions of the two sets (as point sets). Second, we consider either all possible translations
t
(as is the standard approach), or consider only translations that keep the balls of
A+t
disjoint from those of
B
. We propose several exact and approximation algorithms for these problems. In the second part of the article, we note that the Hausdorff distance is sensitive to outliers, and thus consider two variants that are more robust: the root-mean-square (rms) and the summed Hausdorff distance. We propose efficient approximation algorithms for computing the minimum rms and the minimum summed Hausdorff distances under translation, between two point sets in R

d

. In order to obtain a fast algorithm for the summed Hausdorff distance, we propose a deterministic efficient dynamic data structure for maintaining an ϵ-approximation of the 1-median of a set of points in R

d

, under insertions and deletions.
Finding equitable convex partitions of points in a polygon efficiently
Authors: Carlsson John Gunnar , Armbruster Benjamin , Ye Yinyu
Published: September 2010

Previous work has developed algorithms for finding an equitable convex partition that partitions the plane into
n
convex pieces each containing an equal number of red and blue points. Motivated by a vehicle routing heuristic, we look at a related problem where each piece must contain one point and an equal fraction of the area of some convex polygon. We first show how algorithms for solving the older problem lead to approximate solutions for this new equitable convex partition problem. Then we demonstrate a new algorithm that finds an
exact
solution to our problem in
O
(
N n
log
N
) time or operations, where
n
is the number of points,
m
the number of vertices or edges of the polygon, and
N
:=
n
+
m
the sum.
Nitric oxide generation in children with malaria and the NOS2G-954C promoter polymorphism
Authors: Planche Timothy , Macallan Derek C. , Sobande Toni , Borrmann Steffen , Kun Jürgen F. J. , Krishna Sanjeev , Kremsner Peter G.
Published: September 2010

Previous epidemiological studies have demonstrated a protective association between the NOS2G-954C (NOS2Lambaréné) polymorphism in inducible nitric oxide synthase and severe malaria. The polymorphism is commoner in children with uncomplicated compared with severe malaria. We now show that the likely mechanism for such protection is increased flux of nitrogen from arginine to nitric oxide (NO) during episodes of malaria. Forty-seven boys with uncomplicated malaria received an infusion of15N-arginine to measure directly whole body in vivo NO production. The NOS2G-954C genotype previously associated with reduced risk of severe malaria in Gabon was also assessed. Evaluable data were obtained from 40 boys, of whom 6 were NOS2G-954C heterozygotes. Heterozygotes had higher urinary15N nitrate enrichments, 2.3 ± 0.6 vs. 1.4 ± 0.5 atoms percent excess ( P = 0.001) and higher ratios of15N between urine nitrate and plasma arginine (87 ± 11 vs. 57 ± 18%, P = 0.001) consistent with accelerated NO production. We also derived total NO production rates, combining data with total urine production rate and nitrate concentration; these showed no difference by genotype (0.62 ± 0.36, n = 6 vs. 0.83 ± 0.50 μmol/kg·h, n = 16; P = 0.36), but data were confounded by very high variability in measurements of urine output and nitrate concentrations. This study supports the idea that NOS2 genotype protects against severe malaria by increasing NO production during episodes of uncomplicated malaria.
The transcription factor HNF1α regulates expression of chloride-proton exchanger ClC-5 in the renal proximal tubule
Authors: Tanaka Karo , Terryn Sara , Geffers Lars , Garbay Serge , Pontoglio Marco , Devuyst Olivier
Published: September 2010

The Cl−/H+exchanger ClC-5 is essential for the endocytic activity of the proximal tubule cells and the tubular clearance of proteins filtered in the glomeruli. The mechanisms that regulate the expression of ClC-5 in general and its specific expression in the proximal tubule are unknown. In this study, we investigated the hypothesis that the hepatocyte nuclear transcription factor HNF1α, which is predominantly expressed in proximal tubule segments, may directly regulate the expression of ClC-5. In situ hybridization demonstrated that the expression of Clcn5 overlaps with that of Hnf1α in the developing kidney as well as in absorptive epithelia, including the digestive tract and yolk sac. Multiple binding sites for HNF1 were mapped in the 5′-regulatory sequences of the mouse and human Clcn5/CLCN5 genes. The transactivation of the Clcn5/CLCN5 promoter by HNF1α was verified in vitro, and the binding of HNF1α to the Clcn5 promoter in vivo was confirmed by chromatin immunoprecipitation in mouse kidney. The expression of Clcn5 was reduced in the proximal tubule segments of HNF1α-null kidneys, and it was rescued upon transfection of HNF1α-null cells with wild-type but not with mutant HNF1α. These data demonstrate that HNF1α directly regulates the expression of ClC-5 in the renal proximal tubule and yield insights into the mechanisms governing epithelial differentiation and specialized transport activities in the kidney.
Trial-to-Trial Variability of Spike Response of V1 and Saccadic Response Time
Authors: Lee Jungah , Kim HyungGoo R. , Lee Choongkil
Published: September 2010

Single neurons in the primary visual cortex (V1) show variability in spike activity in response to an identical visual stimulus. In the current study, we examined the behavioral significance of the variability in spike activity of V1 neurons for visually guided saccades. We recorded single-cell activity from V1 of monkeys trained to detect and make saccades toward visual targets of varying contrast and analyzed trial-to-trial covariation between the onset time or firing rate of neural response and saccadic response time (RT). Neural latency (NL, the time of the first spike of neural response) was correlated with RT, whereas firing rate (FR) was not. When FR was computed with respect to target onset ignoring NL, a “false” correlation between FR and RT emerged. Multiple regression and partial correlation analyses on NL and FR for predictability of RT variability, as well as a simulation with artificial Poisson spike trains, supported the conclusion that the correlation between FR with respect to target onset and RT was mediated by a correlation between NL and RT, emphasizing the role of trial-to-trial variability of NL for extracting RT-related signals. We attempted to examine laminar differences in RT-related activity. Neurons recorded in the superficial layers tended to show a higher sensitivity to stimulus contrast and a lower correlation with RT compared with those in the lower layers, suggesting a sensory-to-motor transformation within V1 that follows the order of known anatomical connections. These results demonstrate that the trial-to-trial variability of neural response in V1 propagates to the stage of saccade execution, resulting in trial-to-trial variability of RT of a visually guided saccade.
Synergistic Antitumor Activity of Sorafenib in Combination with Epidermal Growth Factor Receptor Inhibitors in Colorectal and Lung Cancer Cells
Authors: Martinelli Erika , Troiani Teresa , Morgillo Floriana , Rodolico Gabriella , Vitagliano Donata , Morelli Maria Pia , Tuccillo Concetta , Vecchione Loredana , Capasso Anna , Orditura Michele , De Vita Ferdinando , Eckhardt S. Gail , Santoro Massimo , Berrino Liberato , Ciardiello Fortunato
Published: September 2010

Purpose: Cancer cell survival, invasion, and metastasis depend on cancer cell proliferation and on tumor-induced angiogenesis. We evaluated the efficacy of the combination of sorafenib and erlotinib or cetuximab.

Experimental Design: Sorafenib, erlotinib, and cetuximab, alone or in combination, were tested in vitro in a panel of non–small cell lung cancer (NSCLC) and colorectal cancer cell lines and in vivo in H1299 tumor xenografts.

Results: Epidermal growth factor receptor (EGFR) ligand mRNAs were expressed in all NSCLC and colorectal cancer cell lines with variable levels ranging from 0.4- to 8.1-fold as compared with GEO colorectal cancer cells. Lung cancer cells had the highest levels of vascular endothelial growth factors (VEGF) A, B, and C, and of VEGF receptors as compared with colorectal cancer cells.

Combined treatments of sorafenib with erlotinib or cetuximab produced combination index values between 0.02 and 0.5, suggesting a significant synergistic activity to inhibit soft agar colony formation in all cancer cell lines, which was accompanied by a marked blockade in mitogen-activated protein kinase and AKT signals. The in vitro migration of H1299 cells, which expressed high levels of both VEGF ligands and receptors, was inhibited by treatment with sorafenib, and this effect was significantly increased by the combination with anti-EGFR drugs. In nude mice bearing established human H1299 xenografts, treatment with the combination of sorafenib and erlotinib or cetuximab caused a significant tumor growth delay resulting in 70 to 90 days increase in mice median overall survival as compared with single-agent sorafenib treatment.

Conclusions: Combination treatment with sorafenib and erlotinib or cetuximab has synergistic antitumor effects in human colorectal and lung cancer cells. Clin Cancer Res; 16(20); 4990–5001. ©2010 AACR.
Balancing act for elderly myeloma
Authors: Palumbo Antonio
Published: September 2010

In this issue of Blood, Waage and colleagues present a phase 3 study comparing the combination melphalan-prednisone-thalidomide (MPT) with melphalan-prednisone plus placebo (MP) for the treatment of elderly patients with multiple myeloma. Though responses were in favor of MPT, they did not translate in prolonged progression-free or overall survival.
PPARγ in Placental Angiogenesis
Authors: Nadra Karim , Quignodon Laure , Sardella Chiara , Joye Elisabeth , Mucciolo Antonio , Chrast Roman , Desvergne Béatrice
Published: September 2010

Peroxisome proliferator-activated receptor γ (PPARγ) is a nuclear receptor involved in diverse biological processes including adipocyte differentiation, glucose homeostasis, and inflammatory responses. Analyses of PPARγ knockout animals have been so far preempted by the early embryonic death of PPARγ−/− embryos as a consequence of the severe alteration of their placental vasculature. Using Sox2Cre/PPARγL2/L2 mice, we obtained fully viable PPARγ-null mice through specific and total epiblastic gene deletion, thereby demonstrating that the placental defect is the unique cause of PPARγ−/− embryonic lethality. The vasculature defects observed in PPARγ−/− placentas at embryonic d 9.5 correlated with an unsettled balance of pro- and antiangiogenic factors as demonstrated by increased levels of proliferin (Prl2c2, PLF) and decreased levels of proliferin-related protein (Prl7d1, PRP), respectively. To analyze the role of PPARγ in the later stage of placental development, when its expression peaks, we treated pregnant wild-type mice with the PPARγ agonist rosiglitazone. This treatment resulted in a disorganization of the placental layers and an altered placental microvasculature, accompanied by the decreased expression of proangiogenic genes such as Prl2c2, vascular endothelial growth factor, and Pecam1. Together our data demonstrate that PPARγ plays a pivotal role in controlling placental vascular proliferation and contributes to its termination in late pregnancy.
Development of Facile Synthetic Methods of Carbon Nanotubes Using a Domestic Microwave Oven
Authors: Takagaki Yusaku , Nguyen-Tran Huy-Danh , Ohta Kazuchika
Published: September 2010

We succeeded in the development of two facile synthetic methods of carbon nanotubes (CNTs) by using a domestic microwave oven and a commercially available small microwave furnace from Art Box™. Our handmade apparatus was cheap and the synthesis of the CNTs took only 5 min. Interestingly, we could selectively synthesize the magnetic nickel-containing CNTs and non-magnetic nickel-free CNTs by our two developed methods.
Calculation of One-Electron Multicenter Integrals of Slater Type Orbitals and Coulomb–Yukawa Like Correlated Interaction Potentials with Integer and Noninteger Indices Using Unsymmetrical One-Range Addition Theorems
Authors: Guseinov I I , Mamedov B A
Published: September 2010

Using expansion formulae for multicenter charge densities of integer and noninteger n Slater type orbitals (ISTO and NISTO) established by one of the authors with the help of unsymmetrical one-range addition theorems of complete orthonormal sets of Ψα-exponential type orbitals (Ψα-ETO), where α is the frictional quantum numbers (α = 1,0, - 1, - 2, … ), we perform the calculations for one-electron multicenter integrals of Slater type orbitals (STO) and Coulomb–Yukawa like correlated interaction potentials (CIP) with integer and noninteger indices (ICIP and NICIP). The convergence of the series is tested by calculating concrete cases for arbitrary values of indices and screening constants of orbitals and potentials. It should be noted that the results for one-electron multicenter integrals presented in this work were not shown in our previous publications. As an example of application, the calculations are performed for the ground state of electronic configuration of molecule BH2 that has the open shell.
Dye-Sensitized Solar Cells Based on D–π–A Fluorescent Dyes with Pyridine Ring Forming Strong Interaction with Nanocrystalline TiO2
Authors: Ooyama Yousuke , Nagano Tomoya , Inoue Shogo , Imae Ichiro , Komaguchi Kenji , Harima Yutaka
Published: September 2010

New-type donor–acceptor π-conjugated (D–π–A) fluorescent dyes OH11, OH14, and OH15 with pyridine, 4-phenylpyridine, and quinoline rings, respectively, as electron-accepting groups have been developed and their photovoltaic performance as dye-sensitized solar cells (DSSCs) are investigated. The short-circuit photocurrent densities (Jsc) of DSSCs using OH11, OH14, and OH15 are 4.88, 3.91, and 1.72 mA cm−2, and the solar energy-to-electricity conversion yields (η) are 1.62, 1.30, and 0.56%, respectively, under a simulated solar light (AM 1.5, 100 mW cm−2). The IR spectra of OH11 and OH14 adsorbed on TiO2 indicate the formation of hydrogen bonding between the pyridine ring of dyes and the hydroxy group of TiO2 surface and the formation of strong coordinate bonding between the pyridine ring of dyes and the Lewis acid site of TiO2 surface. On the other hand, in the IR spectra of OH15 adsorbed on TiO2, only the formation of weak hydrogen bonding was observed. This work suggests that the pyridine rings forming a strong coordinate bonding with the Lewis acid site of TiO2 surface are promising candidates as electron-accepting groups of new D–π–A dye sensitizers for DSSCs.
Comparison of Electron Capture—Atmospheric Pressure Chemical Ionization and Electrospray Ionization for the Analysis of Gambogic Acid and its Main Circulating Metabolite in Dog Plasma
Authors: Yang Jing , Ding Li , Hu Linlin , Jin Shaohong , Liu Wenyuan , Wang Zhenzhong , Xiao Wei , You Qidong , Guo Qinglong
Published: September 2010

Gambogic acid (GA), a promising anticancer candidate, is a polyprenylated xanthone abundant in the resin of Garcinia morella and Garcinia hanburyi. Electron capture–atmospheric pressure chemical ionization (EC-APCI) and electrospray ionization (ESI) techniques, both in the negative ion mode, were evaluated regarding ionization, fragmentation patterns and sensitivity for simultaneous liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of GA and its main circulating metabolite, 10-hydroxygambogic acid (10-OHGA) in dog plasma. Both analytes underwent extensive in-source fragmentation in EC-APCI, which was not desirable for reliable quantification of these analytes, whereas the substitution of ESI for EC-APCI almost eliminated the source instability of both analytes. Negative ion ESI was, therefore, chosen for the development of an LC-MS/MS method for simultaneous determination of these analytes. After protein precipitation by acetonitrile, all analytes were separated on a Luna C18 HST column (50 × 2.0 mm i.d., 2.5 μm) with a mobile phase of 20 mmol L−1 ammonium acetate water solution containing 0.2% acetic acid: acetonitrile (18:82, v/v). The detection was performed on a tandem mass spectrometer using selective reaction monitoring mode. Calibration curves were linear over the range of 10–6000 ng mL−1 for GA and 3–2000 ng mL−1 for 10-OHGA. The method was successfully applied to the pharmacokinetics study of GA injection in six beagle dogs.
Ein Mikrowellensensornetzwerk zur räumlichen Fahrzeug-zu-Fahrzeug- und Fahrzeug-zu-Infrastruktur-Ortung
Authors: Ebelt Randolf , Millner Hendrik , Vossiek Martin
Published: September 2010

In diesem Artikel wird ein System und Verfahren zur funkbasierten Vermessung der relativen räumlichen Position und Ausrichtung von Fahrzeugen untereinander und von Fahrzeugen relativ zu einer Infrastruktur vorgestellt. Ausgehend von einer Menge gemessener und a priori bekannter eindimensionaler Distanzen berechnet ein auf multidimensionaler Skalierung beruhender Algorithmus die räumliche Struktur des gesamten Sensornetzes. Der Ansatz wird anhand einer prototypischen Fahrzeugortungsanwendung demonstriert.
Basic Gestures as Spatiotemporal Reference Frames for Repetitive Dance/Music Patterns in Samba and Charleston
Authors: Leman Marc , Naveda Luiz
Published: September 2010

The goal of the present study is to gain better insight into how dancers establish, through dancing, a spatiotemporal reference frame in synchrony with musical cues. With the aim of achieving this, repetitive dance patterns of samba and Charleston were recorded using a three-dimensional motion capture system. Geometric patterns then were extracted from each joint of the dancer's body. The method uses a body-centered reference frame and decomposes the movement into nonorthogonal periodicities that match periods of the musical meter. Musical cues (such as meter and loudness) as well as action-based cues (such as velocity) can be projected onto the patterns, thus providing spatiotemporal reference frames, or 'basic gestures,' for action-perception couplings. Conceptually speaking, the spatiotemporal reference frames control minimum effort points in action-perception couplings. They reside as memory patterns in the mental and/or motor domains, ready to be dynamically transformed in dance movements. The present study raises a number of hypotheses related to spatial cognition that may serve as guiding principles for future dance/music studies.
Hybrid White Organic Light Emitting Diodes (OLED) Processed by Organic Vapor Phase Deposition
Authors: Boesing Manuel , Lindla Florian , Zimmermann Christoph , van Gemmern Philipp , Bertram Dietrich , Keiper Dietmar , Meyer Nico , Heuken M. , Kalisch Holger , Jansen R. H.
Published: September 2010

White OLED consisting of a fluorescent blue emissive layer combined with a phosphorescent green and a phosphorescent red emissive layer were processed by means of Organic Vapor Phase Deposition (OVPD). Different concepts to tune the color coordinates of the device are discussed with respect to the luminous efficiency. Furthermore, the influence of device aging on the emitted spectrum is being investigated by means of spectrally resolved lifetime measurements.
Synthesis and characterization of donor-acceptor perylene based copolymers
Authors: Kozma Erika , Munno Filomena , Kotowski Dariusz , Bertini Fabio , Luzzati Silvia , Catellani Marinella
Published: September 2010

Two donor-acceptor copolymers containing perylene diimide and oligothiophenes linked through triple bonds have been designed and synthesized by palladium catalyzed Sonogashira coupling reaction. The introduction of the triple bond spacer between the electron-acceptor perylene moieties and the electron donating oligothiophene moieties produces an extended conjugation along the main chain, and produces soluble and high molecular weight copolymers.The thermal, optical and electrochemical properties of these copolymers were examined. The HOMO-LUMO energy levels of these copolymers, along with the photoinduced charge transfer process, probed by photoluminescence quenching and by FTIR photoinduced absorption spectroscopy, in blends with poly(3-hexylthiophene) (P3HT), indicate that they are suitable materials for application as electron acceptor and n-type components in bulk heterojunction solar cells with P3HT.
Synthesis and Magnetic Properties of Pure and Cobalt-Doped Nanocrystalline Bismuth Ferrite
Authors: Montes Gina M , Perales-Perez Oscar , Rentería Boris , Gálvez Marco
Published: September 2010

Applications of nanocrystalline multiferroics in sensor development, massive memory storage or in the fabrication of new devices taking advantage of the electron charge and spin explains the need of investigating various options to synthesize these types of materials. Among promising candidates, Bismuth ferrite (BiFeO3) is a multiferroic material that exhibits ferromagnetism, ferroelectricity and ferroelasticity. The present research is focused on the systematic study of the polyol synthesis of substrate-less nanocrystalline BiFeO3 particles and its structural and magnetic characterization. As an attempt to explore the possibility of tuning the ferrite magnetic properties, host BiFeO3 was doped with cobalt ions in the 5at. % -10at. % range. Our results suggested that the ferrite formation and its properties were strongly dependent on both, the annealing conditions of the precursors and the concentration of cobalt species. Well-crystallized pure BiFeO3 was produced after annealing the precursor powders for one hour at 800oC. Doping with cobalt ions lowered the temperature at which the nanocrystalline BiFeO3 host structure was developed. The saturation magnetization and coercivity in the nanocrystalline ferrite were strongly influenced by the selected annealing temperatures and dopant concentration. These magnetic parameters varied from 0.30 emu/g and 109.5 Oe up to 4.2 emu/g and 988 Oe for pure and 10 at % Co-doped ferrite, respectively.
CuO nanowire–Co3O4 nanoparticle heterostructures and their vertically aligned and horizontally suspended architectures
Authors: Shi Wenwu , Chopra Nitin
Published: September 2010

Well-controlled architectures (aligned or horizontally suspended) of CuO nanowire (average diameter ~75±18 nm)-Co3O4 nanoparticle (average diameter ~7±1 nm) heterostructures were fabricated in a simple and surfactant-free growth approach. This approach coupled microfabrication methods with a thermal growth method and wet-coating technique. The fabricated heterostructures were characterized by high resolution electron microscopy (SEM and TEM) and X-ray Photoelectron Spectroscopy (XPS) for their size, morphology, phases, interfaces, and composition of heterostructures. Finally, CuO nanowire–Cox3O4 nanoparticle heterostructures were utilized as photocatalyst to degrade organic dye (methyl orange) under a wide range of wavelengths (from UV, 265 nm, to visible region, 580 nm).
Antireflective Optical Properties of Colloidal Subwavelength Nanostructured Surfaces
Authors: Liu Bo-Tau , Tang Sheng-Jie
Published: September 2010

Colloidal subwavelength nanostructured surfaces were fabricated by the deposition of uniform silica nanoparticles on a glass substrate by means of electrostatic attraction between charged colloidal particles and charged polyelectrolyte multilayers. The effects of surface morphology via the variation of nanoparticles on the antireflective properties of the nanostructured surfaces were investigated by the analysis of the reflection spectra and the SEM images. The Maxwell's equations were solved by a rigorous coupled-wave analysis (RCWA) to evaluate the experimental results. It was found that the reflective properties revealed by the simulation analysis were similar to the experimental results. The nanostructured surfaces with particles of ~120 nm in diameter yielded the most suitable performance for antireflection with respect to the visible-light region. In addition, the nanostructured surfaces showed the good anti-scratch when the nanoparticles were bound by polyethoxysiloxane.
The Properties of Silica and Hybrid Nanostructures
Authors: Shalav Avi , Elliman Robert , Kim Taehyun
Published: September 2010

SiOx nanowires can be grown via the vapor-liquid-solid growth mechanism using SiO vapor produced during the active oxidation of a Si substrate. The as-grown SiOx nanowire have a range of useful physical properties but can also be used as large surface area substrates for the growth of secondary materials. In this study we report the use of optically active impurities to grow and dope secondary nanowire structures, and the use of simple coating methods to enhance and extend the functionality of these unique nanowire substrates.
Electrical Transport Phenomena of Single ZnO Nanowire Device Directly Measured Using Nano Manipulator
Authors: Yoon Sang Won , Seo Jong-Hyun , Seong Tae-Yeon , Kwon Hoon , Lee Kon Bae , Ahn Jae-Pyoung
Published: September 2010

ZnO nanowire (NW) has potential applications for transparent electrodes, gas sensors, nanoscale optoelectronic devices, piezoresponse force microscopy (PFM) and field effect transistors. In general, we have evaluated the electrical properties of nanowire device from I-V curves measured mainly from the bundle-like ensemble structure of ZnO, not individual ZnO NWs. Most applications require details on the electrical mobility of ZnO NWs. Recently, the electrical transport of single ZnO NWs has been studied only from several devices fabricated by electron-beam lithography. However their I-V curves categorized into three types of resistance, i.e., symmetrical, rectifying and linear shapes due to contact problems between ZnO NWs and electrodes, results in contradictory.

In this paper, we manufactured single NW device using an individual ZnO nanowire, of which the junctions were made by Pt deposition using a focused ion beam (FIB), and performed RTA processes. The single ZnO NW device consists of ZnO-Pt, ZnO-Au and Au-Pt junctions. The electrical transport of the single ZnO NW device was investigated by directly measuring the electrical resistance using nano manipulators from cross-sectioned devices. The device showed a typical Ohmic contact in I-V curves and the resistance was decrease with the RTA temperature. The CL (Cathodoluminescence) and EDS in TEM (Energy dispersive spectroscopy in transmission electron microscopy) measurements were also performed to evaluate the crystallinity (defect level) and chemical composition at the center and edge of the cross-sectioned ZnO NWs. From the results, we found that lots of defects were stored at the surface of ZnO NW and impurities at the junction were abruptly reduced. Therefore, the electrical transport of the single ZnO NW device depends strongly on the crystallinity of the ZnO NW and the C content at the Pt junction. From the electrical transport measured on the cross sectioned device, the ZnO-Au junction acted as the fastest transport path among ZnO-Pt, ZnO-Au and Au-Pt junctions in the single ZnO NW device.
A Critical Assessment of RNA-Mediated Materials Synthesis
Authors: Franzen Stefan , Leonard Donovan
Published: September 2010

RNA- and DNA-mediation or templating of materials has been used to synthesize nanometer scale wires, and CdS nanoparticles. However, RNA and DNA have the potential to act as catalysts, which could be valuable tools in the search for new routes to materials synthesis. RNA has the ability to catalyze splicing and cutting of other RNA molecules. Catalytic activity has been extended to more general classes of reactions for both RNA and DNA using in vitro selection methods. However, catalytic activity in materials synthesis is a more recent idea that has not yet found great application. The first example of RNA-mediated evolutionary materials synthesis is discussed with specific data examples that show incompatibility of reagents in the solvent system utilized. The hydrophobic reagent Pd2(DBA)3, used as a metal precursor, was observed to spontaneously form nanostructures composed of Pd2(DBA)3 or Pd(DBA)3 rather than palladium nanoparticles, as originally reported 1. A case study of this materials synthesis example is described including the complimentary use of multi-length scale techniques including transmission electron microscopy (TEM), selected area electron diffraction (SAED), scanning TEM (STEM), electron energy loss spectroscopy (EELS), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and optical microscopy (OM). This example raises important questions regarding the extent to which non-aqueous solvents should be used in nucleic acid-mediated processes, the nature of selections in enzyme and materials development, and the requirement for chemical compatibility of the precursor molecules. The importance of good characterization tools at every stage of an in vitro selection is illustrated with concrete examples given. In order to look at the way forward for nucleic acid-mediated materials synthesis, an examination of the chemical interaction of nucleic acids with various precursors is considered. Application of density functional theory calculations provides one means to predict reactivity and compatibility. The repertoire of chemical interactions in the nucleic acids is considered vis-à-vis common metals and metal chalcogenides. The case is made for the need for water-soluble syntheses and well-controlled kinetics in order to achieve the control that is theoretically possible using nucleic-acids as a synthetic tool.
Experimental investigations into the mechanical properties of the collagen fibril-noncollagenous protein (NCP) interface in antler bone
Authors: Hang Fei , Barber Asa H
Published: September 2010

Antler is an extraordinary bone tissue that displays significant overall toughness when compared to other bone materials. The origin of this toughness is due to the complex interaction between the nanoscale constituents as well as structural hierarchy in the antler material. Of particular interest is the mechanical performance of the interface between the collagen fibrils and considerably smaller volume of non-collagenous protein (NCP) between these fibrils. This paper directly examines the mechanical properties of isolated volumes of antler using combined in situ atomic force microscopy (AFM)-scanning electron microscopy (SEM) experiments. The antler material at the nanoscale is approximated to a fiber reinforced composite, with composite theory used to evaluate the interfacial shear stresses generated between the individual collagen fibrils and NCP during mechanical loading.
Biotransformation of sucrose into 5-hydroxy-2-hydroxymethyl-γ-pirone by Aspergillus flavus
Authors: Ferreira Nelson R. , Sarquis Maria Inez M. , Alves Cláudio N. , Santos Alberdan S.
Published: September 2010

The sucrose hydrolysis and the preference of consumption of glucose instead of fructose were investigated for the production of 5-hydroxy-2-hydroxymethyl-γ-pyrone (HHMP) in the presence of Aspergillus flavus IOC 3974 cultivated in liquid Czapeck medium. Standardized 0.5g of pellets were transferred as inoculum into twelve conical flasks of 250 ml containing 100 ml of medium with different sucrose concentration, which was kept at 120 rpm and 28"C for 16 days without pH adjustment. Aliquots of 500μl of the broth culture were withdrawn at 24 h intervals and analyzed. The major yield of HHMP was 26g l-1 in 120g l-1 of sucrose. At these conditions, A. flavus produced an invertase capable of hydrolyzing 65% of total sucrose concentration in 24h, and an isomerase capable of converting fructose into glucose. In this work, it focused the preference for glucose and, then, of fructose by A. flavus and the strategy used to produce HHMP.
Population structure of Rudgea parquioides (Rubiaceae), a shade-tolerant shrub species, in Southern Brazil
Authors: Cardoso Fernanda C.G. , Salvalaggio Ana P.B. , Marques Márcia C.M.
Published: September 2010

The expectations that shade-tolerant forest species show 1) a population structure composed by a high amount of small individuals, and 2) biomass allocation for diameter higher than for height growth, were tested for Rudgea parquioides, a typical shrub in Southern Brazil. We described the size structure (height and stem diameter) and allometrical relations of a R. parquioides population by counting and measuring all the individuals in a 725m² area in the municipality of Curitiba (25"25'S; 49"19'W). A total of 916 individuals (12,634 ind.ha-1) were recorded in the area. The firstexpectation was supported, since distribution by height and diameter classes showed a predominance of small individuals (skewness coefficients > 1). On the other hand, the regression between height and stem base diameter showed slope β < 1, which indicates that growth in height is higher than in diameter, not supporting the second expectation. These results show that life strategies in shade-tolerant species may imply in more trade-off combinations than previously described.
Political philosophy, ethnology, and time: a study of the notion of historical handicap
Authors: Feres Jr João
Published: September 2010

This article starts by identifying the crucial importance of the notion of historical handicap for the present-day social sciences of Latin America. Such notion is not an original invention made by Latinamericanists. On the contrary, I demonstrate that the genealogy of the notion of historical handicap must be sought in the tradition of Western political philosophy. Such genealogy must take into account the way it was integrated into ethnological descriptions. When and how did the Other become the backward, the primitive? While this relation was secondary for ancient Greek thought, theories of historical development became the main source of ethnological categories in the modern era. Interestingly enough, this modern synthesis suited the practical purpose of justifying two successive waves of European imperialistic: the era of discoveries, and 19th century colonialism. The article concludes by raising questions about the present role and application of the social sciences.
Significatividade e verdade
Authors: Braida Celso R.
Published: September 2010

O presente artigo enfoca a concepção semântica da noção de verdade e a interpreta como uma tese acerca da prioridade da significatividade em relação à verdade. A partir disso, argumenta-se que a concepção deflacionista da verdade é inadequada, com base na alegação de que a significatividade envolve relações inferenciais e referenciais e na alegação de que a predicação da verdade envolve a atribuição de existência.
Biópsia pulmonar incisional por toracoscopia paraxifoide transdiafragmática com dois portais em cães
Authors: Basso Paula C. , Raiser Alceu G. , Brun Maurício V. , Guizzo Junior Nédio , Feranti João P.S. , Motta Adriana C. , Bortolini Carlos E. , Muller Daniel C.M.
Published: September 2010

As doenças respiratórias observadas na clínica médica de pequenos animais são numerosas, assim como as possibilidades diagnósticas, dentre as quais encontram-se os exames laboratoriais, os estudos radiográficos, os lavados broncoalveolares e as biópsias. Na presente pesquisa avaliaram-se os resultados da toracoscopia paraxifoide transdiafragmática para a realização de biópsia pulmonar em cães, sendo utilizados para tanto, 13 animais clinicamente sadios. Sob anestesia geral, produziu-se pneumotórax no volume de 30ml kg-1 de ar ambiente para cada hemitórax. O acesso foi obtido a partir de dois trocartes, posicionados entre o apêndice xifoide e o arco costal, os quais transfixaram o diafragma. O primeiro portal foi empregado para a passagem do endoscópio e o segundo para a utilização de pinça saca-bocado, empregada na obtenção de biópsia. Em seguida, a pinça foi removida e um dreno torácico foi posicionado através do portal. Durante os procedimentos, aferiram-se as frequências respiratória e cardíaca, a saturação de oxigênio, as pressões arterial média e venosa central e os parâmetros hemogasométricos. Os drenos foram removidos num período de até 48 horas de pós-operatório, verificando-se mínima produção de ar e/ou líquido. Concluiu-se se tratar de uma técnica rápida, segura e sem complicações trans e pós-operatórias, permitindo aquisição de material suficiente para a avaliação histológica do pulmão.
Effect of medroxy-progesterone acetate on follicular growth and endometrial cycloxygenase-2 (COX-2) expression during the bovine estrous cycle
Authors: Portela Valério M. , Farias Alexandre M. , Moraes José C. Ferrugem , Gonçalves Paulo Bayard D. , Veiga Angela P. Medeiros , Oliveira João F.
Published: September 2010

The objective of this study was to evaluate the effect of medroxy-progesterone acetate (MAP) with or without estradiol benzoate (EB) on follicular growth during the estrous cycle in cattle. In the first experiment, Hereford cows were synchronized with a synthetic analogue of PGF2 alpha and were treated with two different doses of MAP (250 or 500 mg) with or without EB for 7 days starting on day 8 of the estrous cycle. Follicular growth was inhibited (P<0.05) in all cows except controls and those receiving 250mg MAP without EB. Seventy-five percent of the animals (15/20) showed estrus on days 21 and 22 of the cycle rather than at MAP withdrawal, demonstrating that these treatments did not induce estrus. To determine whether the EB treatment altered endometrial sensitivity to oxytocin and thus the luteolytic cascade, multiparous pre-synchronized cows received 5 mg of EB followed 6 hours later with 50 IU of oxytocin (OT; n=9). Eight hours after EB injection, endometrial fragments were collected from the cows on days 4, 13 and 17 of the estrous cycle and COX-2 gene expression was measured by PCR. EB increased COX-2 mRNA levels only on day 17 of the estrous cycle (P<0.05). In conclusion, MAP alone or associated with EB is able to suppress bovine follicular growth. However, EB in the presence of MAP is not efficient to induce luteolysis in cows when injected on day 8 of the estrous cycle.