bluuebunny/crossref_metadata_2025 huggingface dataset:
Origins of individual differences in anxiety proneness: a twin/adoption study of the anxiety‐related scales from the Karolinska Scales of Personality (KSP)
Authors: Gustavsson J. P. , Pedersen N. L. , Åsberg M. , Schalling D.
Published: August 2007

The genetic and environmental origins of individual differences in scores on the anxiety‐proneness scales from the Karolinska Scales of Personality were explored using a twin/adoption study design in a sample consisting of 15 monozygotic twin pairs reared apart, and 26 monozygotic and 29 dizygotic twin pairs reared together. The results showed that genetic factors accounted for individual differences in scores on the psychasthenia and somatic anxiety scales. The genetic determinants were not specific to each scale, but were common to both scales. Shared‐rearing environmental determinants were important for individual differences in lack of assertiveness and psychic anxiety, and were common to both scales. Individual differences in muscular tension were found to be attributable to the effects of correlated environments. The most important factor explaining individual differences for all scales was the non‐shared environment component. The evidence for an aetiologically heterogeneous anxiety‐proneness construct emphasizes the appropriateness of a multi dimensional approach to anxiety proneness.
ULTRASONOGRAPHIC ASSESSMENT OF THE CANINE SCIATIC NERVE
Authors: BENIGNI LIVIA , CORR SANDRA A. , LAMB CHRISTOPHER R.
Published: August 2007

To describe the ultrasonographic technique for investigation of the canine sciatic nerve, four canine cadaver pelvic limbs, two live healthy dogs, and five canine patients with suspected peripheral sciatic nerve lesions were examined with a high‐resolution linear ultrasound transducer. The caudal part of the lumbosacral trunk and the origin of the sciatic nerve were visualized through the greater ischiatic foramen. The two components of the sciatic nerve, common peroneal and tibial nerves, were distinguished along the entire length of the nerve, until they branched at the level of the distal femur. In healthy live dogs they appeared as two adjacent hypoechoic tubular structures with internal echotexture of discontinuous hyperechoic bands, surrounded by a thin rim of highly echogenic tissue. The common peroneal component had a smaller diameter and was on the cranial aspect of the tibial component. An ultrasonographic lesion compatible with a peripheral nerve sheath tumor was found in one dog. Improved understanding of the ultrasonographic anatomy of the sciatic nerve supports clinical use of this modality.
ULTRASONOGRAPHIC FEATURES OF EXTRAHEPATIC BILIARY OBSTRUCTION IN 30 CATS
Authors: GAILLOT HUGUES A. , PENNINCK DOMINIQUE G. , WEBSTER CYNTHIA R. L. , CRAWFORD SYBIL
Published: August 2007

The goals of our study were to review the ultrasonographic features of spontaneous extrahepatic biliary obstruction in cats and to determine whether these features can assist in differentiating tumor, inflammation, and choleliths as the cause of obstruction. Thirty cats with a presurgical ultrasound examination and confirmed extrahepatic biliary obstruction were studied. A common bile duct diameter over 5 mm was present in 97% of the cats with extrahepatic biliary obstruction. Gallbladder dilation was seen in <50% of the cats. Ultrasound identified all obstructive choleliths (calculus or plugs) in the common bile duct. However, neither common bile duct diameter nor appearance or any other ultrasonographic feature allowed differentiation between tumor and inflammation as the cause of obstruction. A short duration of clinical signs (10 days or less) seemed to be associated with obstructive cholelithiasis.
IMAGING DIAGNOSIS—EXTRAHEPATIC BILIARY TRACT OBSTRUCTION SECONDARY TO A DUODENAL FOREIGN BODY IN A CAT
Authors: SANTA DANIELE DELLA , SCHWEIGHAUSER ARIANE , FORTERRE FRANCK , LANG JOHANN
Published: August 2007

A 13‐month‐old, neutered female domestic shorthaired cat was evaluated for vomiting, anorexia, and lethargy. The cat was icteric and hyperbilirubinemic. Radiographically a partially radiolucent proximal duodenal foreign body was suspected. Ultrasonographically, there was a foreign body at the level of the duodenal papilla and dilation of the common bile duct and cystic duct; a diagnosis of extrahepatic biliary tract obstruction secondary to a duodenal foreign body was made. Sonographic findings were confirmed at surgery and a duodenal foreign body was removed. This information defines duodenal foreign body as a cause of extrahepatic biliary obstruction in cats.
POTENTIAL FOR INTENSITY‐MODULATED RADIATION THERAPY TO PERMIT DOSE ESCALATION FOR CANINE NASAL CANCER
Authors: VAUDAUX CATHERINE , SCHNEIDER UWE , KASER‐HOTZ BARBARA
Published: August 2007

We evaluated the impact of inverse planned intensity‐modulated radiation therapy (IMRT) on the dose–volume histograms (DVHs) and on the normal tissue complication probabilities (NTCPs) of brain and eyes in dogs with nasal tumors. Nine dogs with large, caudally located nasal tumors were planned using conventional techniques and inverse planned IMRT for a total prescribed dose of 52.5 Gy in 3.5 Gy fractions. The equivalent uniform dose for brain and eyes was calculated to estimate the normal tissue complication probability (NTCP) of these organs. The NTCP values as well as the DVHs were used to compare the treatment plans. The dose distribution in IMRT plans was more conformal than in conventional plans. The average dose delivered to one‐third of the brain was 10 Gy lower with the IMRT plan compared with conventional planning. The mean partial brain volume receiving 43.6 Gy or more was reduced by 25.6% with IMRT. As a consequence, the NTCPs were also significantly lower in the IMRT plans. The mean NTCP of brain was two times lower and at least one eye could be saved in all patients planed with IMRT. Another possibility with IMRT is dose escalation in the target to improve tumor control while keeping the NTCPs at the same level as for conventional planning.
WHEN DOES A REGULATION BECOME A TAKING? THE UNITED STATES SUPREME COURT'S MOST RECENT PRONOUNCEMENTS
Authors: KRAMER DANIEL C.
Published: August 2007

Keystone Bituminous Coal, Irving, and Nollan are thus each consistent with paths taken in relevant precedents–the former two with “multifactor balancing” cases such as Penn Central and the latter with “enduring invasion equals taking” decisions such as Loretto v. TeleprompterM. However, can these twosets of precedents themselves be reconciled? I believe that the correct answer is “yes,” and that we therefore have another reason for asserting that Keystone Bituminous Coal and Nollan are consistent with each other. The tests are compatible in that the Court will first ask itself whether the regulation results in a longstanding occupation of property. If the answer is “yes,” it will declare a seizure then and there. Only if the answer if “no” will it proceed to balance.
Kinetic Analysis of Volatile Formation in Milk Subjected to Pressure‐Assisted Thermal Treatments
Authors: Vazquez‐Landaverde P.A. , Qian M.C. , Torres J.A.
Published: August 2007

ABSTRACT:  Volatile formation in milk subjected to pressure‐assisted thermal processing (PATP) was investigated from a reaction kinetic analysis point of view to illustrate the advantages of this technology. The concentration of 27 volatiles of different chemical class in milk subjected to pressure, temperature, and time treatments was fitted to zero‐, 1st‐, and 2nd‐order chemical reaction models. Temperature and pressure effects on rate constants were analyzed to obtain activation energy (Ea) and activation volume (ΔV*) values. Hexanal, heptanal, octanal, nonanal, and decanal followed 1st‐order kinetics with rate constants characterized by Ea values decreasing with pressure reflecting negative ΔV* values. Formation of 2‐methylpropanal, 2,3‐butanedione, and hydrogen sulfide followed zero‐order kinetics with rate constants increasing with temperature but with unclear pressure effects. Ea values for 2‐methylpropanal and 2,3‐butanedione increased with pressure, that is, ΔV* > 0, whereas values for hydrogen sulfide remained constant, that is, ΔV*= 0. The concentration of all other volatiles, including methanethiol, remained unchanged in pressure‐treated samples, suggesting large negative ΔV* values. The concentration of methyl ketones, including 2‐pentanone, 2‐hexanone, 2‐heptanone, 2‐octanone, 2‐nonanone, 2‐decanone, and 2‐undecanone, was independent of pressure and pressure‐holding time. PATP promoted the formation of few compounds, had no effect on some, and inhibited the formation of volatiles reported to be factors of the consumer rejection of “cooked” milk flavor. The kinetic behavior observed suggested that new reaction formation mechanisms were not likely involved in volatile formation in PATP milk. The application of the Le Chatelier principle frequently used to explain the high quality of pressure‐treated foods, often with no supporting experimental evidence, was not necessary.
Effects of Pressure‐Shift Freezing and Pressure‐Assisted Thawing on Sea Bass (Dicentrarchus labrax) Quality
Authors: Tironi V. , LeBail A. , De Lamballerie M.
Published: August 2007

ABSTRACT:  Effects of pressure‐shift freezing and/or pressure‐assisted thawing on the quality of sea bass muscle were evaluated and compared with conventional (air‐blast) frozen and thawed samples. Microstructural analysis showed a marked decrease of muscle cell damage for pressure‐assisted frozen samples. According to differential scanning calorimetry (DSC), protein extractability, and SDS‐PAGE results, high‐pressure treatment (200 MPa) produced a partial denaturation with aggregation and insolubilization of the myosin, as well as alterations of the sarcoplasmic proteins. Only small differences between high‐pressure processes (freezing or/and thawing) were registered. High‐pressure‐treated systems led to a decrease of water holding capacity but differences between high‐pressure and conventional methods disappeared after cooking. Muscle color showed important alterations due to high‐pressure treatments (increasing L* and b*).
An Investigation of the Relationship Between Acoustic Emission, Vibration, Noise, and Cavitation Structures on a Kaplan Turbine
Authors: Rus Tomaž , Dular Matevž , Širok Brane , Hočevar Marko , Kern Igor
Published: August 2007

The goal of the study was to explain the relationship between different acoustic signals and visual appearance of cavitation. Measurements of acoustic emission, vibration, and noise were performed on a Kaplan turbine model, with only two blades, in a cavitating condition. Since a model with only two blades was used, most of the side effects were eliminated, and it was concluded that the cavitation itself is the source of the recorded signal. Results showed an interesting relationship between the extent of the cavitation and the recorded data from sensors. At a decreasing cavitation number, the recorded amplitudes from all measurements first rose, experienced a local maximum, then fell to a local minimum, and finally rose again. The cavitation was also visually observed. It was concluded from the measurements that there are distinct correlations between acoustic emission, vibration, and noise on one side and the topology, extent, and type of cavitation structures on the other side. A physical explanation for the phenomenon was introduced and included in a semi-empirical model that links the visual appearance of cavitation on the blade of the turbine to the generated noise and vibration.
Simulation of Contaminant Transport in a Fractured Porous Aquifer
Authors: Fomin Sergei , Chugunov Vladimir , Hashida Toshiyuki
Published: August 2007

Solute transport in the fractured porous confined aquifer is modeled by the advection-dispersion equation with fractional time derivative of order γ, which may vary from 0 to 1. Accounting for diffusion in the surrounding rock mass leads to the introduction of an additional fractional time derivative of order 1∕2 in the equation for solute transport. The closed-form solutions for concentrations in the aquifer and surrounding rocks are obtained for the arbitrary time-dependent source of contamination located in the inlet of the aquifer. Based on these solutions, different regimes of contamination of the aquifers with different physical properties are modeled and analyzed.
Pop Fly
Authors: Berenbaum May
Published: August 2007

Fly
.
By Steven Connor
. Reaktion, London, 2006. 222 pp. Paper, $19.95, £12.95. ISBN 9781861892942. Animal.

The author surveys roles that flies, broadly construed, have played in myth, literature, poetry, painting, film, and biology.
When Fear Is Near: Threat Imminence Elicits Prefrontal-Periaqueductal Gray Shifts in Humans
Authors: Mobbs Dean , Petrovic Predrag , Marchant Jennifer L. , Hassabis Demis , Weiskopf Nikolaus , Seymour Ben , Dolan Raymond J. , Frith Christopher D.
Published: August 2007

Humans, like other animals, alter their behavior depending on whether a threat is close or distant. We investigated spatial imminence of threat by developing an active avoidance paradigm in which volunteers were pursued through a maze by a virtual predator endowed with an ability to chase, capture, and inflict pain. Using functional magnetic resonance imaging, we found that as the virtual predator grew closer, brain activity shifted from the ventromedial prefrontal cortex to the periaqueductal gray. This shift showed maximal expression when a high degree of pain was anticipated. Moreover, imminence-driven periaqueductal gray activity correlated with increased subjective degree of dread and decreased confidence of escape. Our findings cast light on the neural dynamics of threat anticipation and have implications for the neurobiology of human anxiety-related disorders.
Domain Architecture of Pyruvate Carboxylase, a Biotin-Dependent Multifunctional Enzyme
Authors: Maurice Martin St. , Reinhardt Laurie , Surinya Kathy H. , Attwood Paul V. , Wallace John C. , Cleland W. Wallace , Rayment Ivan
Published: August 2007

Biotin-dependent multifunctional enzymes carry out metabolically important carboxyl group transfer reactions and are potential targets for the treatment of obesity and type 2 diabetes. These enzymes use a tethered biotin cofactor to carry an activated carboxyl group between distantly spaced active sites. The mechanism of this transfer has remained poorly understood. Here we report the complete structure of pyruvate carboxylase at 2.0 angstroms resolution, which shows its domain arrangement. The structure, when combined with mutagenic analysis, shows that intermediate transfer occurs between active sites on separate polypeptide chains. In addition, domain rearrangements associated with activator binding decrease the distance between active-site pairs, providing a mechanism for allosteric activation. This description provides insight into the function of biotin-dependent enzymes and presents a new paradigm for multifunctional enzyme catalysis.
Breakdown of the Born-Oppenheimer Approximation in the F+
o
-D
2
→ DF + D Reaction
Authors: Che Li , Ren Zefeng , Wang Xingan , Dong Wenrui , Dai Dongxu , Wang Xiuyan , Zhang Dong H. , Yang Xueming , Sheng Liusi , Li Guoliang , Werner Hans-Joachim , Lique François , Alexander Millard H.
Published: August 2007

The reaction of F with H
2
and its isotopomers is the paradigm for an exothermic triatomic abstraction reaction. In a crossed-beam scattering experiment, we determined relative integral and differential cross sections for reaction of the ground F(
2
P
3/2
) and excited F*(
2
P
1/2
) spin-orbit states with D
2
for collision energies of 0.25 to 1.2 kilocalorie/mole. At the lowest collision energy, F* is ∼1.6 times more reactive than F, although reaction of F* is forbidden within the Born-Oppenheimer (BO) approximation. As the collision energy increases, the BO-allowed reaction rapidly dominates. We found excellent agreement between multistate, quantum reactive scattering calculations and both the measured energy dependence of the F*/F reactivity ratio and the differential cross sections. This agreement confirms the fundamental understanding of the factors controlling electronic nonadiabaticity in abstraction reactions.
CHD1 Motor Protein Is Required for Deposition of Histone Variant H3.3 into Chromatin in Vivo
Authors: Konev Alexander Y. , Tribus Martin , Park Sung Yeon , Podhraski Valerie , Lim Chin Yan , Emelyanov Alexander V. , Vershilova Elena , Pirrotta Vincenzo , Kadonaga James T. , Lusser Alexandra , Fyodorov Dmitry V.
Published: August 2007

The organization of chromatin affects all aspects of nuclear DNA metabolism in eukaryotes. H3.3 is an evolutionarily conserved histone variant and a key substrate for replication-independent chromatin assembly. Elimination of chromatin remodeling factor CHD1 in
Drosophila
embryos abolishes incorporation of H3.3 into the male pronucleus, renders the paternal genome unable to participate in zygotic mitoses, and leads to the development of haploid embryos. Furthermore, CHD1, but not ISWI, interacts with HIRA in cytoplasmic extracts. Our findings establish CHD1 as a major factor in replacement histone metabolism in the nucleus and reveal a critical role for CHD1 in the earliest developmental instances of genome-scale, replication-independent nucleosome assembly. Furthermore, our results point to the general requirement of adenosine triphosphate (ATP)–utilizing motor proteins for histone deposition in vivo.
European Multicenter Evaluation of Commercial Enzyme Immunoassays for Detecting Norovirus Antigen in Fecal Samples
Authors: Gray Jim J. , Kohli Evelyne , Ruggeri Franco M. , Vennema Harry , Sánchez-Fauquier Alicia , Schreier Eckart , Gallimore Chris I. , Iturriza-Gomara Miren , Giraudon Helene , Pothier Pierre , Di Bartolo Ilaria , Inglese Nadia , de Bruin Erwin , van der Veer Bas , Moreno Silvia , Montero Vanessa , de Llano Marí C. , Höhne Marina , Diedrich Sabine M.
Published: August 2007

A total of 2,254 fecal samples were tested in a European multicenter evaluation of commercially available norovirus antigen detection assays. Two commercial enzyme immunoassays, IDEIA Norovirus (Oxoid; Thermo Fisher Scientific, Ely, United Kingdom) and RIDASCREEN Norovirus (R-Biopharm, Darmstadt, Germany), were included in the evaluation, and their performance was compared with the results of reverse transcription-PCR (RT-PCR). Included in the evaluation were samples collected in sporadic cases of gastroenteritis, samples from outbreaks in which two or more samples were collected, well-characterized samples representing genotypes currently cocirculating within Europe, and samples collected from patients with gastroenteritis caused by a pathogen other than norovirus. The sensitivities and specificities of the IDEIA Norovirus and RIDASCREEN Norovirus assays were 58.93 and 43.81% and 93.91 and 96.37%, respectively, compared with RT-PCR. The sensitivities of both assays for outbreak investigations improved when six or more samples from an outbreak were examined. The IDEIA Norovirus assay exhibited reactivity to a broader range of norovirus genotypes than the RIDASCREEN Norovirus assay, which showed genotype-dependent sensitivities. The results indicate that, if used, these assays should serve as screening assays and the results should be confirmed by RT-PCR.
Two Trypanosome-Specific Proteins Are Essential Factors for 5S rRNA Abundance and Ribosomal Assembly in
Trypanosoma brucei
Authors: Hellman Kristina M. , Ciganda Martin , Brown Silvia V. , Li Jinlei , Ruyechan William , Williams Noreen
Published: August 2007

We have previously identified and characterized two novel nuclear RNA binding proteins, p34 and p37, which have been shown to bind 5S rRNA in
Trypanosoma brucei
. These two proteins are nearly identical, with one major difference, an 18-amino-acid insert in the N-terminal region of p37, as well as three minor single-amino-acid differences. Homologues to p34 and p37 have been found only in other trypanosomatids, suggesting that these proteins are unique to this ancient family. We have employed RNA interference (RNAi) studies in order to gain further insight into the interaction between p34 and p37 with 5S rRNA in
T. brucei
. In our p34/p37 RNAi cells, decreased expression of the p34 and p37 proteins led to morphological alterations, including loss of cell shape and vacuolation, as well as to growth arrest and ultimately to cell death. Disruption of a higher-molecular-weight complex containing 5S rRNA occurs as well as a dramatic decrease in 5S rRNA levels, suggesting that p34 and p37 serve to stabilize 5S rRNA. In addition, an accumulation of 60S ribosomal subunits was observed, accompanied by a significant decrease in overall protein synthesis within p34/p37 RNAi cells. Thus, the loss of the trypanosomatid-specific proteins p34 and p37 correlates with a diminution in 5S rRNA levels as well as a decrease in ribosome activity and an alteration in ribosome biogenesis.
Class I Histone Deacetylase Thd1p Promotes Global Chromatin Condensation in
Tetrahymena thermophila
Authors: Parker Kathryn , Maxson Julia , Mooney Alissa , Wiley Emily A.
Published: August 2007

Class I histone deacetylases (HDACs) regulate DNA-templated processes such as transcription. They act both at specific loci and more generally across global chromatin, contributing to acetylation patterns that may underlie large-scale chromatin dynamics. Although hypoacetylation is correlated with highly condensed chromatin, little is known about the contribution of individual HDACs to chromatin condensation mechanisms. Using the ciliated protozoan
Tetrahymena thermophila
, we investigated the role of a specific class I HDAC, Τhd1p, in the reversible condensation of global chromatin. In this system, the normal physiological response to cell starvation includes the widespread condensation of the macronuclear chromatin and general repression of gene transcription. We show that the chromatin in Thd1p-deficient cells failed to condense during starvation. The condensation failure correlated with aberrant hyperphosphorylation of histone H1 and the overexpression of
CDC2
, encoding the major histone H1 kinase. Changes in the rate of acetate turnover on core histones and in the distribution of acetylated lysines 9 and 23/27 on histone H3 isoforms that were found to correlate with normal chromatin condensation were absent from Thd1p mutant cells. These results point to a role for a class I HDAC in the formation of reversible higher-order chromatin structures and global genome compaction through mechanisms involving the regulation of H1 phosphorylation and core histone acetylation/deacetylation kinetics.
DNA Microarray-Based Detection and Identification of Fungal Pathogens in Clinical Samples from Neutropenic Patients
Authors: Spiess Birgit , Seifarth Wolfgang , Hummel Margit , Frank Oliver , Fabarius Alice , Zheng Chun , Mörz Handan , Hehlmann Rüdiger , Buchheidt Dieter
Published: August 2007

The increasing incidence of invasive fungal infections (IFI) in immunocompromised patients emphasizes the need to improve diagnostic tools. We established a DNA microarray to detect and identify DNA from 14 fungal pathogens (
Aspergillus fumigatus
,
Aspergillus flavus
,
Aspergillus terreus
,
Candida albicans
,
Candida dubliniensis
,
Candida glabrata
,
Candida lusitaniae
,
Candida tropicalis
,
Fusarium oxysporum
,
Fusarium solani
,
Mucor racemosus
,
Rhizopus microsporus
,
Scedosporium prolificans
, and
Trichosporon asahii
) in blood, bronchoalveolar lavage, and tissue samples from high-risk patients. The assay combines multiplex PCR and consecutive DNA microarray hybridization. PCR primers and capture probes were derived from unique sequences of the 18S, 5.8S, and internal transcribed spacer 1 regions of the fungal rRNA genes. Hybridization with genomic DNA of fungal species resulted in species-specific hybridization patterns. By testing clinical samples from 46 neutropenic patients with proven, probable, or possible IFI or without IFI, we detected
A. flavus
,
A. fumigatus
,
C. albicans
,
C. dubliniensis
,
C. glabrata
,
F. oxysporum
,
F. solani
,
R. microsporus
,
S. prolificans
, and
T. asahii
. For 22 of 22 patients (5 without IFI and 17 with possible IFI), negative diagnostic results corresponded with negative microarray data. For 11 patients with proven (
n
= 4), probable (
n
= 2), and possible IFI (
n
= 5), data for results positive by microarray were validated by other diagnostic findings. For 11 of 11 patients with possible IFI, the microarray results provided additional information. For two patients with proven and probable invasive aspergillosis, respectively, microarray results were negative. The assay detected genomic DNA from 14 fungal pathogens from the clinical samples, pointing to a high significance for improving the diagnosis of IFI.
Functional Modulation of the Geminivirus AL2 Transcription Factor and Silencing Suppressor by Self-Interaction
Authors: Yang Xiaojuan , Baliji Surendranath , Buchmann R. Cody , Wang Hui , Lindbo John A. , Sunter Garry , Bisaro David M.
Published: August 2007

The DNA genomes of geminiviruses have a limited coding capacity that is compensated for by the production of small multifunctional proteins. The AL2 protein encoded by members of the genus
Begomovirus
(e.g.,
Tomato golden mosaic virus
) is a transcriptional activator, a silencing suppressor, and a suppressor of a basal defense. The related L2 protein of
Beet curly top virus
(genus
Curtovirus
) shares the pathogenicity functions of AL2 but lacks transcriptional activation activity. It is known that AL2 and L2 can suppress local silencing by interacting with adenosine kinase (ADK) and can suppress basal defense by interacting with SNF1 kinase. However, how the activities of these viral proteins are regulated remains an unanswered question. Here, we provide some answers by demonstrating that AL2, but not L2, interacts with itself. The zinc finger-like motif (CCHC) is required but is not sufficient for AL2 self-interaction. Alanine substitutions for the invariant cysteine residues that comprise the motif abolish self-interaction or cause aberrant subnuclear localization but do not abolish interaction with ADK and SNF1. Using bimolecular fluorescence complementation, we show that AL2:AL2 complexes accumulate primarily in the nucleus, whereas AL2:ADK and L2:ADK complexes accumulate mainly in the cytoplasm. Further, the cysteine residue mutations impair the ability of AL2 to activate the coat protein promoter but do not affect local silencing suppression. Thus, AL2 self-interaction correlates with nuclear localization and efficient activation of transcription, whereas AL2 and L2 monomers can suppress local silencing by interacting with ADK in the cytoplasm.
Three-Dimensional Structure of the Human Cytomegalovirus Cytoplasmic Virion Assembly Complex Includes a Reoriented Secretory Apparatus
Authors: Das Subhendu , Vasanji Amit , Pellett Philip E.
Published: August 2007

Human cytomegalovirus (HCMV) induces profound changes in infected cell morphology, including a large cytoplasmic inclusion that corresponds to the virion assembly complex (AC). In electron micrographs, the AC is a highly vacuolated part of the cytoplasm. Markers of cellular secretory organelles have been visualized at the outer edge of the AC, and we recently showed that a marker for early endosomes (i.e., early endosome antigen 1) localizes to the center of the AC. Here, we examined the relationship between the AC and components of the secretory apparatus, studied temporal aspects of the dramatic infection-induced cytoplasmic remodeling, examined the three-dimensional structure of the AC, and considered the implications of our observations for models of HCMV virion maturation and egress. We made three major observations. First, in addition to being relocated, the expression levels of some organelle markers change markedly during the period while the AC is developing. Second, based on three-dimensional reconstructions from z-series confocal microscopic images, the observed concentric rings of vesicles derived from the several compartments (Golgi bodies, the
trans
-Golgi network [TGN], and early endosomes) are arranged as nested cylinders of organelle-specific vesicles. Third, the membrane protein biosynthetic and exocytic pathways from the endoplasmic reticulum to the Golgi bodies, TGN, and early endosomes are in an unusual arrangement that nonetheless allows for a conventional order of biosynthesis and transport. Our model of AC structure suggests a mechanism by which the virus can regulate the order of tegument assembly.
The Capsid and Tegument of the Alphaherpesviruses Are Linked by an Interaction between the UL25 and VP1/2 Proteins
Authors: Coller Kelly Elizabeth , Lee Joy I-Hsuan , Ueda Aki , Smith Gregory Allan
Published: August 2007

How alphaherpesvirus capsids acquire tegument proteins remains a key question in viral assembly. Using pseudorabies virus (PRV), we have previously shown that the 62 carboxy-terminal amino acids of the VP1/2 large tegument protein are essential for viral propagation and when transiently expressed as a fusion to green fluorescent protein relocalize to nuclear capsid assemblons following viral infection. Here, we show that localization of the VP1/2 capsid-binding domain (VP1/2cbd) into assemblons is conserved in herpes simplex virus type 1 (HSV-1) and that this recruitment is specifically on capsids. Using a mutant virus screen, we find that the protein product of the UL25 gene is essential for VP1/2cbd association with capsids. An interaction between UL25 and VP1/2 was corroborated by coimmunoprecipitation from cells transiently expressing either HSV-1 or PRV proteins. Taken together, these findings suggest that the essential function of the VP1/2 carboxy terminus is to anchor the VP1/2 tegument protein to capsids. Furthermore, UL25 encodes a multifunctional capsid protein involved in not only encapsidation, as previously described, but also tegumentation.
Herpes Simplex Virus Mutants with Multiple Substitutions Affecting DNA Binding of UL42 Are Impaired for Viral Replication and DNA Synthesis
Authors: Jiang Changying , Hwang Ying T. , Wang Guangliang , Randell John C. W. , Coen Donald M. , Hwang Charles B. C.
Published: August 2007

Herpes simplex virus mutants with single substitutions that decrease DNA binding by the DNA polymerase processivity subunit UL42 are only modestly impaired for viral replication. In this study, recombinant viruses harboring two or four of these mutations were constructed. The more substitutions, the more severe the defects in viral replication and DNA synthesis, suggesting that DNA binding by UL42 is important for these processes.
AN LP-BASED APPROACH TO OUTLIERS DETECTION IN FUZZY REGRESSION ANALYSIS
Authors: NASRABADI EBRAHIM , HASHEMI S. MEHDI , GHATEE MEHDI
Published: August 2007

When the outliers exist in the data set, fuzzy regression gives incorrect results. A few number of researchers considered this problem and proposed linear-programming-based methods and fuzzy least-squares methods to deal with the outliers problem. In this paper, we develop a new model along with a linear-programming-based approach for computation of fuzzy regression models. The problem of outliers is modeled with this approach. Two examples are illustrated to compare the performance of proposed approach with those given in literature. Results from numerical examples show that our approach gives good solutions.
IMPOSSIBILITY OF PARTIAL SWAPPING OF QUANTUM INFORMATION
Authors: CHAKRABARTY I.
Published: August 2007

It is a well–known fact that a quantum state |ψ(θ, ϕ)〉 is represented by a point on the Bloch sphere, characterized by two parameters θ and ϕ. Here in this work, we find out another impossible operation in quantum information theory. We name this impossibility as 'Impossibility of partial swapping of quantum information'. By this we mean that if two unknown quantum states are given at the input port, there exists no physical process, consistent with the principles of quantum mechanics, by which we can partially swap either of the two parameters θ and ϕ between these two quantum states. In this work, we provided the impossibility proofs for the qubits (i.e. the quantum states taken from two-dimensional Hilbert space) and this impossible operation can be shown to hold in higher dimensions also.
THE CHIEF TECHNOLOGY OFFICER (CTO) IN LITERATURE AND PRACTICE — A REVIEW AND RESULTS FROM FIELD RESEARCH IN JAPAN
Authors: HERSTATT CORNELIUS , TIETZE FRANK , NAGAHIRA AKIO , PROBERT DAVID
Published: August 2007

This paper presents a literature review discussing empirical as well as conceptual papers concerning the CTO — the Chief Technology Officer — his tasks, responsibilities and authority and his relations with other corporate functions. It further presents first results of a CTO survey conducted in the Japanese electrical engineering industry in the fall of 2006. Based on both, a set of propositions is presented which the authors test via a large forthcoming empirical study in the same industry.
MANAGING THE EXPLORATION/EXPLOITATION PARADOX IN NEW PRODUCT DEVELOPMENT: HOW TOP EXECUTIVES DEFINE THEIR FIRM'S INNOVATION TRAJECTORY
Authors: NEMANICH LOUISE A. , KELLER ROBERT T. , VERA DUSYA
Published: August 2007

Building on structuration theory, we present a conceptual model that illustrates how top executives can guide their firm's new product development (NPD) strategy along a desired innovation trajectory combining different degrees of exploration and exploitation. The model addresses the interplay between executives' actions and the organization's controlling structures in the form of roles, rules, and resources. We describe how transformational leadership behaviors by top executives can be effective in the paradox management needed to shift the exploration or exploitation emphasis of a NPD strategy, whereas transactional leadership can be effective in maintaining a consistent strategic course. In doing this, we propose visual representations of innovation trajectories as wave functions as helpful tools to describe NPD strategies. Illustrative examples of structural changes that support strategic change toward greater exploration or greater exploitation are also offered.
Fire-Balls in Pion Multiple Production
Authors: Chinellato Jose A. , Dobrigkeit Carola , Filho J. Bellandi , Lattes Cesar M. G. , Menon Marcio J. , Navia O. Carlos E. , Pemmaraju Ammiraju , Sawayanagi Kotaro , Shibuya Edison H. , Turtelli Armando , Amato Neuza M. , Arata Naoyuki , Castro F. M. Oliveira , Maldonado Regina H. C. , Aoki Hiroshi , Fujimoto Yoichi , Hasegawa Shunichi , Semba Hiroshi , Tamada Masanobu , Tanaka Kojiro , Yamashita Seibun , Shibata Toru , Yokoi Kei , Kumano Hiroshi , Ohsawa Akinori , Tabuki Takaaki
Published: August 2007

The article describes a study of the multiple pion production through observation of gamma-rays produced by nuclear interactions at the target layer of the emulsion chambers exposed at Chacaltaya, Bolivia, 5200 m above sea level. The analysis was focused on 80 events with ΣEr>20 TeV, well above the detection threshold of the X-ray film spot scanning, ∼3 TeV. The distribution of gamma-rays is constructed on their energy, pt, and emission angle, and the comparison is made with the results from the simulation calculations based on FNAL hydrogen bubble chamber events and ISR minimum bias events. The cosmic-ray results are significantly out of the simple scaling extrapolation, showing higher rapidity density nr. and increasing pt. Recent p̄-p collider experiments gave the confirming results.

From the plot of events in the diagram of nr. and 〈pt〉, the events are classified into two types; Mirim-jets (meaning small jets, nr= 2∼3, 〈pt〉∼140 MeV/c) and Açu-jets (large jets, nr = 6∼8, 〈pt〉∼220 MeV/c), with nearly equal frequency of production. Mirim-jets are those on the scaling extrapolation from the lower energy region of accelerators, while increasing rate of Açu-jets with energy is causing the scaling break. The analysis with the fire-ball model shows that the Mirim-jets are consistently interpreted as production and decay of a small fire-ball (a fire-ball quantum called H-quantum) with rest energy of 2∼3 GeV and decay temperature of about 130 MeV. While, the Açu-jets necessitate introduction of a heavy fire-ball (SH-quantum) with rest energy of 20∼30 GeV.

The study of atmospheric interactions (A-jets) shows presence of events with still larger nr and higher pt, which are called Guaçu-jets. One C-jet is found to be a candidate of this type. The Guaçu-jets require presence of a huge fire-ball (UH-quantum) of rest energy 200∼300 GeV.

Discussions are made on physical implication of the fire-ball model, particularly on those quanta of a fire-ball.
Glomerular filtration into the subpodocyte space is highly restricted under physiological perfusion conditions
Authors: Neal Christopher R. , Muston P. Robert , Njegovan David , Verrill Rebecca , Harper Steven J. , Deen William M. , Bates David O.
Published: August 2007

Production of urine is initiated by fluid and solute flux across the glomerular filtration barrier. Recent ultrastructural studies have shown that under extreme conditions of no filtration, or very high filtration, a restriction to flow is predicted in a space underneath the podocyte cell body or its processes, the subpodocyte space (SPS). The SPS covered up to two-thirds of the glomerular filtration barrier (GFB) surface. The magnitude of this restriction to flow suggested that it might be unlikely that filtration into and flow through the SPS would contribute significantly to total flow across the entire GFB under these conditions. To determine whether the SPS has similar properties under normal physiological conditions, we have carried out further three-dimensional reconstruction of rat glomeruli perfused at physiologically normal hydrostatic and colloid osmotic pressures. These reconstructions show that the sub-podocyte space is even more restricted under these conditions, with a mean height of the SPS of 0.34 μm, mean pathlength of 6.7 ± 1.4 μm, a mean width of the SPS exit pore of 0.15 ± 0.05 μm, and length of 0.25 ± 0.05 μm. Mathematical modeling of this SPS based on a circular flow model predicts that the resistance of these dimensions is 2.47 times that of the glomerular filtration barrier and exquisitely sensitive to changes in the dimensions of the SPS exit pore (SEP), indicating that the SEP could be the principal regulator of the extravascular pressure in the SPS. This suggests a physiological role of the podocyte in the regulation of glomerular fluid flux across most of the GFB.
Lead, at low levels, accelerates arteriolopathy and tubulointerstitial injury in chronic kidney disease
Authors: Roncal Carlos , Mu Wei , Reungjui Sirirat , Kim Kyung Mee , Henderson George N. , Ouyang Xiaosen , Nakagawa Takahiko , Johnson Richard J.
Published: August 2007

Chronic lead exposure has been epidemiologically linked with hypertension and renal disease. Clinical studies suggest that low lead levels may contribute to renal progression. However, experimental studies have not examined whether low levels of lead accelerate progression in experimental chronic renal disease. Sprague-Dawley rats were administered lead (L; 150 ppm in drinking water, n = 16) for 4 wk, followed by remnant kidney (RK) surgery with continuation of lead for an additional 12 wk; control rats ( n = 9) were treated similarly but did not receive lead. Lead treatment was well tolerated and resulted in modest elevations in whole blood lead levels (26.4 ± 4.5 vs. 1 ± 0 μg/dl, week 16, P < 0.001). Lead treatment was associated with higher systolic blood pressure ( P < 0.05) and worse renal function (creatinine clearance 1.4 ± 0.4 vs. 1.8 ± 0.5 ml/min, RK+L vs. RK, P < 0.05), and with a tendency for greater proteinuria (6.6 ± 6.1 vs. 3.6 ± 1.5 mg protein/mg creatinine, RK+L vs. RK, P = 0.08). While glomerulosclerosis tended to be worse in lead-treated rats (37.6 ± 11 vs. 28.8 ± 2.3%, RK+L vs. RK, P = 0.06), the most striking finding was the development of worse arteriolar disease ( P < 0.05), peritubular capillary loss ( P < 0.05), tubulointerstitial damage, and macrophage infiltration ( P < 0.05) in association with significantly increased renal expression of monocyte chemoattractant protein-1 mRNA. In conclusion, lead accelerates chronic renal disease, primarily by raising blood pressure and accelerating microvascular and tubulointerstitial injury.
Bursting in Substantia Nigra Pars Reticulata Neurons In Vitro: Possible Relevance for Parkinson Disease
Authors: Ibáñez-Sandoval Osvaldo , Carrillo-Reid Luis , Galarraga Elvira , Tapia Dagoberto , Mendoza Ernesto , Gomora Juan C. , Aceves Jorge , Bargas José
Published: August 2007

Projection neurons of the substantia nigra reticulata (SNr) convey basal ganglia (BG) processing to thalamocortical and brain stem circuits responsible for movement. Two models try to explain pathological BG performance during Parkinson disease (PD): the rate model, which posits an overexcitation of SNr neurons due to hyperactivity in the indirect pathway and hypoactivity of the direct pathway, and the oscillatory model, which explains PD as the product of pathological pattern generators disclosed by dopamine reduction. These models are, apparently, incompatible. We tested the predictions of the rate model by increasing the excitatory drive and reducing the inhibition on SNr neurons in vitro. This was done pharmacologically with bath application of glutamate agonist N-methyl-d-aspartate and GABAA receptor blockers, respectively. Both maneuvers induced bursting behavior in SNr neurons. Therefore synaptic changes forecasted by the rate model induce the electrical behavior predicted by the oscillatory model. In addition, we found evidence that CaV3.2 Ca2+ channels are a critical step in generating the bursting firing pattern in SNr neurons. Other ion channels involved are: hyperpolarization-activated cation channels, high-voltage-activated Ca2+ channels, and Ca2+-activated K+ channels. However, although these channels shape the temporal structure of bursting, only CaV3.2 Ca2+ channels are indispensable for the initiation of the bursting pattern.
Patch-Clamp Analysis of Gene-Targeted Vomeronasal Neurons Expressing a Defined V1r or V2r Receptor: Ionic Mechanisms Underlying Persistent Firing
Authors: Ukhanov Kirill , Leinders-Zufall Trese , Zufall Frank
Published: August 2007

Sensory neurons in the mouse vomeronasal organ consist of two major groups, apical and basal, that project to different brain regions, express unique sets of receptors, and serve distinct functions. Electrical properties of these two subpopulations, however, have not been systematically characterized. V1rb2-tau-GFP and V2r1b-tau-GFP tagged vomeronasal sensory neurons (VSNs) were selected as prototypical apical or basal VSNs, respectively, and their biophysical properties were analyzed in acute slices that minimized cell damage. Basal V2r1b-expressing VSNs had voltage-gated conductances, and especially Na+ (Nav) and Ca2+ (Cav) currents, that were substantially larger than those observed in apical V1rb2 VSNs, although the resting membrane potential, input resistance, and membrane capacitance were similar in both cell types. Of several types of Cav currents, T-type and L-type Cav currents contributed to action potential firing, and both currents alone were capable of generating oscillatory Ca2+ spikes. The L-type Cav current was uniquely coupled to a BK large-conductance K+ current, and interplay between these channels played a critical role in repolarizing spikes and maintaining persistent firing in VSNs. Larger Nav and Cav conductances, along with a more positive inactivation voltage of the Nav current in the V2r1b VSNs, contributed to the larger spike amplitude and higher spike frequency induced by depolarizing current in these cells compared with V1rb2 VSNs. Basal GFP-negative VSNs and V2r1b VSNs responded to prolonged depolarization with persistent, but adapting discharge that could be relevant in sensory adaptation. Collectively, these results suggest a novel mechanism for regulating and encoding neuronal activity in the accessory olfactory system.
Crossed Commissural Pathways in the Spinal Hindlimb Enlargement Are Not Necessary for Right–Left Hindlimb Alternation During Turtle Swimming
Authors: Samara Ramsey F. , Currie Scott N.
Published: August 2007

We examined the coordination between right and left hindlimbs during voluntary forward swimming in adult red-eared turtles, before and after midsagittal section of the spinal cord hindlimb enlargement (segments D8–S2) or the enlargement plus the first preenlargement segment (D7–S2). Our purpose was to assess the role of crossed commissural axons in these segments for right–left hindlimb alternation during voluntary locomotion. Midsagittal splitting severed commissural fibers and separated the right and left halves of the posterior spinal cord. Adult turtles ( n = 9) were held by a band clamp around the shell in a water-filled tank while digital video of forward swimming was recorded from below and computer analyzed with motion analysis software. In a subset of these animals ( n = 5), we also recorded electromyograms from hip extensor and/or hip flexor muscles on both sides. Surprisingly, splitting spinal segments D8–S2 or D7–S2 did not affect the strength of out-of-phase coordination between right and left hindlimbs, although hindlimb movement amplitudes were reduced compared with presurgical controls. These results show that commissural axons in the hindlimb enlargement and preenlargement cord are not necessary for right–left hindlimb alternation during voluntary swimming. We suggest that alternating propriospinal drive from the right and left sides of the forelimb enlargement maintains the out-of-phase coordination of right and left hindlimbs in the bisected-cord preparation. Our data support the hypothesis that descending propriospinal (forelimb–hindlimb) and crossed commissural (hindlimb–hindlimb) spinal cord pathways function together as redundant mechanisms to sustain right–left hindlimb alternation during turtle locomotion.
Analysis of Rhythmic Patterns Produced by Spinal Neural Networks
Authors: Mor Y. , Lev-Tov A.
Published: August 2007

A network of spinal neurons known as central pattern generator (CPG) produces the rhythmic motor patterns required for coordinated swimming, walking, and running in mammals. Because the output of this network varies with time, its analysis cannot be performed by statistical methods that assume data stationarity. The present work uses short-time Fourier (STFT) and wavelet-transform (WT) algorithms to analyze the nonstationary rhythmic signals produced in isolated spinal cords of neonatal rats during activation of the CPGs. The STFT algorithm divides the time series into consecutive overlapping or nonoverlapping windows and repeatedly applies the Fourier transform across the signal. The WT algorithm decomposes the signal using a family of wavelets varying in scale, resulting in a set of wavelet coefficients presented onto a continuous frequency range over time. Our studies revealed that a Morlet WT algorithm was the tool of choice for analyzing the CPG output. Cross-WT and wavelet coherence were used to determine interrelations between pairs of time series in time and frequency domain, while determining the critical values for statistical significance of the coherence spectra using Monte Carlo simulations of white-noise series. The ability of the cross-Morlet WT and cross-WT coherence algorithms to efficiently extract the rhythmic parameters of complex nonstationary output of spinal pattern generators over a wide range of frequencies with time is demonstrated in this work under different experimental conditions. This ability can be exploited to create a quantitative dynamic portrait of experimental and clinical data under various physiological and pathological conditions.