bluuebunny/crossref_metadata_2025 huggingface dataset:
Audiovisual biofeedback improves diaphragm motion reproducibility in MRI
Authors: Kim Taeho , Pollock Sean , Lee Danny , O'Brien Ricky , Keall Paul
Published: October 2012

Purpose:

In lung radiotherapy, variations in cycle‐to‐cycle breathing results in four‐dimensional computed tomography imaging artifacts, leading to inaccurate beam coverage and tumor targeting. In previous studies, the effect of audiovisual (AV) biofeedback on the external respiratory signal reproducibility has been investigated but the internal anatomy motion has not been fully studied. The aim of this study is to test the hypothesis that AV biofeedback improves diaphragm motion reproducibility of internal anatomy using magnetic resonance imaging (MRI).

Methods:

To test the hypothesis 15 healthy human subjects were enrolled in an ethics‐approved AV biofeedback study consisting of two imaging sessions spaced ∼1 week apart. Within each session MR images were acquired under free breathing and AV biofeedback conditions. The respiratory signal to the AV biofeedback system utilized optical monitoring of an external marker placed on the abdomen. Synchronously, serial thoracic 2D MR images were obtained to measure the diaphragm motion using a fast gradient‐recalled‐echo MR pulse sequence in both coronal and sagittal planes. The improvement in the diaphragm motion reproducibility using the AV biofeedback system was quantified by comparing cycle‐to‐cycle variability in displacement, respiratory period, and baseline drift. Additionally, the variation in improvement between the two sessions was also quantified.

Results:

The average root mean square error (RMSE) of diaphragm cycle‐to‐cycle displacement was reduced from 2.6 mm with free breathing to 1.6 mm (38% reduction) with the implementation of AV biofeedback (p‐value < 0.0001). The average RMSE of the respiratory period was reduced from 1.7 s with free breathing to 0.3 s (82% reduction) with AV biofeedback (p‐value < 0.0001). Additionally, the average baseline drift obtained using a linear fit was reduced from 1.6 mm/min with free breathing to 0.9 mm/min (44% reduction) with AV biofeedback (p‐value = 0.012). The diaphragm motion reproducibility improvements with AV biofeedback were consistent with the abdominal motion reproducibility that was observed from the external marker motion variation.

Conclusions:

This study was the first to investigate the potential of AV biofeedback to improve the motion reproducibility of internal anatomy using MRI. The study demonstrated the significant improvement in diaphragm motion reproducibility using AV biofeedback combined with MRI. This system can potentially provide clinically beneficial motion management of internal anatomy in MRI and radiotherapy.
Feathered Non-Avian Dinosaurs from North America Provide Insight into Wing Origins
Authors: Zelenitsky Darla K. , Therrien François , Erickson Gregory M. , DeBuhr Christopher L. , Kobayashi Yoshitsugu , Eberth David A. , Hadfield Frank
Published: October 2012

Fancy Feathers

In the past few decades, an increasing number of dinosaurs have been shown to have possessed feathers. While it seems likely that feathers themselves may have evolved for thermoregulation, the original function of wings has been less clear and remained a matter of debate. Based on examination of three Theropod specimens from the genus
Ornothomimus
,

Zelenitsky
et al.

(p.
510
) conclude that the feathered wing may have evolved not for locomotion or prey capture (the animals were herbivores), but rather as a courtship display. All of the individuals examined had a covering consisting of short filamentous feathers, but the adult specimens, which would have reached sexual maturity, also had long shafted feathers on their forelimbs.
Comment on “Conspecific Negative Density Dependence and Forest Diversity”
Authors: Dickie Ian A. , Hurst Jennifer M. , Bellingham Peter J.
Published: October 2012

Johnson and colleagues (Reports, 18 May 2012, p. 904) claim that conspecific negative density dependence is a pervasive mechanism driving forest diversity, especially for rare tree species. We show that their results are due to a statistical bias in their analysis caused by the exclusion of joint absences.
Chiral Cyclopentadienyl Ligands as Stereocontrolling Element in Asymmetric C–H Functionalization
Authors: Ye Baihua , Cramer Nicolai
Published: October 2012

Forced Asymmetry in Cp

The cyclopentadienyl (Cp) ligand—a pentagon of carbons—is a common feature in transition metal catalysts, but chiral variants of the structure have rarely been applied to asymmetric reactions. Two studies now demonstrate distinct approaches to rendering a Cp-derived rhodium catalyst enantioselective in a tandem carbon-hydrogen activation-ring closure reaction that couples olefins with benzamides (see the Perspective by

Wang and Glorius
). Hyster
et al.

(p.
500
) tethered a biotin derivative to the Cp ligand to enable docking in a chiral streptavidin protein cavity, which in turn was engineered to further optimize catalytic performance.
Ye and Cramer
(p.
504
) appended chiral substituents on the Cp framework to bias the rest of the coordination environment around the metal center.
Regulatory T Cells Increase the Avidity of Primary CD8
+
T Cell Responses and Promote Memory
Authors: Pace Luigia , Tempez Andy , Arnold-Schrauf Catharina , Lemaitre Fabrice , Bousso Philippe , Fetler Luc , Sparwasser Tim , Amigorena Sebastian
Published: October 2012

Treg-ulating Immune Responses

There are many checks and balances to keep the immune system from running amok. One of the most critical is a specialized population of T cells, called regulatory T cells (T
regs
). In their absence, a lethal autoimmune disease develops in both humans and mice. Although T
regs
are well known for their suppression of autoimmune responses, how they modulate responses to infectious agents is less well understood. Using inducible deletion of T
regs
in mice,

Pace
et al.

(p.
532
) showed that T
regs
are important for shaping the avidity of CD8
+
T cell responses. In the absence of T
regs
, CD8
+
T cell responses were of lower avidity, and the CD8
+
T cells were more responsive to lower-affinity antigens. When T
regs
were absent, stable interactions between T cell and antigen-presenting cells were increased as a result of higher amounts of chemokine expression in the lymph nodes. T
reg
depletion also resulted in a lower-avidity CD8
+
T cell response to infection with the bacterial pathogen
Listeria monocytogenes
.
Roots of
Origin
Darwin's Ghosts
The Secret History of Evolution / In Search of the First Evolutionists

by Rebecca Stott

Spiegel and Grau, New York, 2012. 415 pp. $27. ISBN 9781400069378. Bloomsbury, London. £25. ISBN 9781408809082.
Authors: Firestein Stuart
Published: October 2012

Stott recounts the engaging stories of Darwin's intellectual forebears.
Worries of a Genomic Futurist
Transhumanist Dreams and Dystopian Nightmares
The Promise and Peril of Genetic Engineering

by Maxwell J. Mehlman

Johns Hopkins University Press, Baltimore, 2012. 286 pp. $29.95. ISBN 9781421406695.
Authors: Goldman Michael A.
Published: October 2012

Believing that we will eventually reengineer the human species, Mehlman considers the implications of doing so and some of the mistakes we may make.
The Risks of Overfishing
Authors: Pikitch Ellen K.
Published: October 2012

Current global fisheries jeopardize not only individual species but also the overall integrity of marine ecosystems.
Prison Terms for L'Aquila Experts Shock Scientists
Authors: Cartlidge Edwin
Published: October 2012

A judge in the central Italian town of L'Aquila has handed down manslaughter sentences of 6 years to each of seven experts who gave advice ahead of the deadly earthquake that struck here in 2009.
Congratulations! Now Get to Work
Authors:   Science News Staff
Published: October 2012

Regardless of his margin of victory, the president will need all the help he can get in dealing with several intractable problems.
For Once, Science Is an Issue in Race for a Seat in Congress
Authors: Cho Adrian
Published: October 2012

A physicist takes on a longtime friend of science in a tight Illinois race in which research matters.
Want to Tear Down Your Rival? Here's What Might Work Best
Authors: Marshall Eliot
Published: October 2012

A new study of negative political ads shows that timing and audience may be the keys to success.
LIFE SCIENCE TECHNOLOGIES: Epigenomics: The New Technologies of Chromatin Analysis
Authors: Perkel Jeffrey M.
Published: October 2012

Multicellular organisms are essentially clonal. Every cell possesses the same DNA as every other. So what distinguishes a liver cell from a neuron? Epigenetics, that constellation of noncoding RNAs, protein-DNA interactions, and molecular modifications that govern which genes are expressed and which stay silent. Epigenetic mechanisms influence processes from stem cell differentiation to cancer, and researchers are keen to understand how these events differ at the genomic scale–the so-called epigenome. The problem is daunting, but the research community is resourceful. The epigenome has never seemed closer.
Preliminary Evaluation of the Safety and Efficacy of Standard Intravenous Immunoglobulins in Pregnant Women with Primary Cytomegalovirus Infection
Authors: Polilli Ennio , Parruti Giustino , D'Arcangelo Francesca , Tracanna Elisa , Clerico Luigi , Savini Vincenzo , D'Antonio Francesco , Rosati Maurizio , Manzoli Lamberto , D'Antonio Domenico , Nigro Giovanni
Published: October 2012

Hyperimmune globulins were reported to prevent and treat fetal cytomegalovirus (CMV) infection during pregnancy. Here, we report that infusions of standard human intravenous immunoglobulin significantly increase CMV IgG titers and avidity indexes in pregnant women, paving the way to their use for passive transfer of maternal CMV humoral immunity to fetuses. Preliminary data on perinatal outcomes of the first 67 newborns are encouraging.
Draft Genome Sequence Determination for Cystic Fibrosis and Chronic Granulomatous Disease Burkholderia multivorans Isolates
Authors: Varga John J. , Losada Liliana , Zelazny Adrian M. , Brinkac Lauren , Harkins Derek , Radune Diana , Hostetler Jessica , Sampaio Elizabeth P. , Ronning Catherine M. , Nierman William C. , Greenberg David E. , Holland Steven M. , Goldberg Joanna B.
Published: October 2012

Burkholderia multivorans
is a Gram-negative bacterium and a member of the
Burkholderia cepacia
complex, which is frequently associated with respiratory infections in people with cystic fibrosis (CF) and chronic granulomatous disease (CGD). We are reporting the genome sequences of 4
B. multivorans
strains, 2 from CF patients and 2 from CGD patients.
Draft Genome Sequence of Fusobacterium nucleatum ChDC F128, Isolated from a Periodontitis Lesion
Authors: Park Soon-Nang , Kong Si-Won , Kim Hwa-Sook , Park Mo-Se , Lee Jee-Won , Cho Eugene , Lim Yun Kyong , Choi Mi-Hwa , Chang Young-Hyo , Shin Jeong Hwan , Park Hong-Seog , Choi Sang-Haeng , Kook Joong-Ki
Published: October 2012

Fusobacterium nucleatum
is classified into five subspecies.
F. nucleatum
ChDC F128 was isolated from a periodontitis lesion and proposed as a new subspecies based on the comparison of the nucleotide sequences of the RNA polymerase beta subunit and zinc protease genes. Here, we report the draft genome sequence of the strain.
Genome Sequence of Lactococcus raffinolactis Strain 4877, Isolated from Natural Dairy Starter Culture
Authors: Meslier Victoria , Loux Valentin , Renault Pierre
Published: October 2012

The nonstarter lactic acid bacterium
Lactococcus raffinolactis
is prevalent in a wide range of environments, such as the dairy environment, but little is known about this species. Here, we present the draft genome of
Lactococcus raffinolactis
strain 4877, isolated from a natural mesophilic dairy starter culture.
Prevention of False Resistance Results Obtained in Testing the Susceptibility of Mycobacterium tuberculosis to Pyrazinamide with the Bactec MGIT 960 System Using a Reduced Inoculum
Authors: Piersimoni Claudio , Mustazzolu Alessandro , Giannoni Federico , Bornigia Stefano , Gherardi Giancarlo , Fattorini Lanfranco
Published: October 2012

The susceptibility of 211 clinical isolates of
Mycobacterium tuberculosis
complex (201
M. tuberculosis
and 10
Mycobacterium bovis
isolates) to pyrazinamide (PZA) was assessed by the nonradiometric Bactec MGIT 960 system (M960). Detection of PZA resistance was followed by a repeat testing using a reduced inoculum (RI) of 0.25 ml instead of 0.5 ml. According to the first M960 analysis, resistance was observed in 55 samples. In the RI assay, 32 samples turned out to be susceptible and 23 proved to be resistant (58.2% false positivity). The Bactec 460 assay confirmed as resistant those strains detected by the RI assay, while discrepant results were found susceptible. Mutation analysis performed on 13
M. tuberculosis
isolates detected
pncA
mutations in 11 samples. On the basis of our data, we suggest using the RI assay to confirm all PZA resistance results obtained with the standard M960 assay. Further studies are required to confirm our findings.
European Surveillance for Pantropic Canine Coronavirus
Authors: Decaro Nicola , Cordonnier Nathalie , Demeter Zoltan , Egberink Herman , Elia Gabriella , Grellet Aurélien , Le Poder Sophie , Mari Viviana , Martella Vito , Ntafis Vasileios , von Reitzenstein Marcela , Rottier Peter J. , Rusvai Miklos , Shields Shelly , Xylouri Eftychia , Xu Zach , Buonavoglia Canio
Published: October 2012

Highly virulent pantropic canine coronavirus (CCoV) strains belonging to subtype IIa were recently identified in dogs. To assess the distribution of such strains in Europe, tissue samples were collected from 354 dogs that had died after displaying systemic disease in France (
n
= 92), Hungary (
n
= 75), Italy (
n
= 69), Greece (
n
= 87), The Netherlands (
n
= 27), Belgium (
n
= 4), and Bulgaria (
n
= 1). A total of 124 animals tested positive for CCoV, with 33 of them displaying the virus in extraintestinal tissues. Twenty-four CCoV strains (19.35% of the CCoV-positive dogs) detected in internal organs were characterized as subtype IIa and consequently assumed to be pantropic CCoVs. Sequence and phylogenetic analyses of the 5′ end of the spike protein gene showed that pantropic CCoV strains are closely related to each other, with the exception of two divergent French viruses that clustered with enteric strains.
Screening of Male Patients for Trichomonas vaginalis with Transcription-Mediated Amplification in a Community with a High Prevalence of Sexually Transmitted Infection
Authors: Munson Kimber L. , Napierala Maureen , Munson Erik , Schell Ronald F. , Kramme Timothy , Miller Cheryl , Hryciuk Jeanne E.
Published: October 2012

Trichomonas vaginalis
infection in males has been largely uncharacterized. Past reports indicated increased susceptibility to other sexually transmitted infection (STI) agents such as human immunodeficiency virus and
Neisseria gonorrhoeae
with concurrent
T. vaginalis
infection. This warrants a more thorough review of male
T. vaginalis
incidence. A retrospective 3-year investigation of transcription-mediated amplification (TMA)-based urethral swab and first-void urine screening for
T. vaginalis
within a regional health care system was performed to address
T. vaginalis
prevalence in males. Of 622 total samples tested, 6.6% were positive for
T. vaginalis
. Delineation of all specimens by ZIP code of patient residence revealed 11 predominant ZIP codes with respect to testing volume and detection rates. Within these 11 ZIP codes, representing 78.3% of total testing volume, urine was the preferred specimen source compared to urethral swabs. Seven of these 11 ZIP codes contained majority African American populations. The aggregate
T. vaginalis
detection rate trended higher than that of the remaining four ZIP codes, which were comprised primarily of Caucasian populations (8.9% versus 5.0%, respectively;
P
= 0.15). The average age of a
T. vaginalis
-infected male (39.9 years) was significantly greater than those for
Chlamydia trachomatis
or
N. gonorrhoeae
(27.6 and 25.9 years, respectively;
P
< 0.001). Given the significant rate of
T. vaginalis
detection, with age distribution analogous to that reported in females, TMA-based detection of
T. vaginalis
can be a routine constituent within a comprehensive STI screening panel for males in high-prevalence STI communities.
A Transmembrane Domain and GxxxG Motifs within L2 Are Essential for Papillomavirus Infection
Authors: Bronnimann Matthew P. , Chapman Janice A. , Park Chad K. , Campos Samuel K.
Published: October 2012

During cellular invasion, human papillomavirus type 16 (HPV16) must transfer its viral genome (vDNA) across the endosomal membrane prior to its accumulation at nuclear PML bodies for the establishment of infection. After cellular uptake, the capsid likely undergoes pH-dependent disassembly within the endo-/lysosomal compartment, thereby exposing hidden domains in L2 that facilitate membrane penetration of L2/vDNA complexes. In an effort to identify regions of L2 that might physically interact with membranes, we have subjected the L2 sequence to multiple transmembrane (TM) domain prediction algorithms. Here, we describe a conserved TM domain within L2 (residues 45 to 67) and investigate its role in HPV16 infection.
In vitro
, the predicted TM domain adopts an alpha-helical structure in lipid environments and can function as a real TM domain, although not as efficiently as the bona fide TM domain of PDGFR. An L2 double point mutant renders the TM domain nonfunctional and blocks HPV16 infection by preventing endosomal translocation of vDNA. The TM domain contains three highly conserved GxxxG motifs. These motifs can facilitate homotypic and heterotypic interactions between TM helices, activities that may be important for vDNA translocation. Disruption of some of these GxxxG motifs resulted in noninfectious viruses, indicating a critical role in infection. Using a ToxR-based homo-oligomerization assay, we show a propensity for this TM domain to self-associate in a GxxxG-dependent manner. These data suggest an important role for the self-associating L2 TM domain and the conserved GxxxG motifs in the transfer of vDNA across the endo-/lysosomal membrane.
Pathogenesis of Neonatal Herpes Simplex 2 Disease in a Mouse Model Is Dependent on Entry Receptor Expression and Route of Inoculation
Authors: Kopp Sarah J. , Karaba Andrew H. , Cohen Laura K. , Banisadr Ghazal , Miller Richard J. , Muller William J.
Published: October 2012

Herpes simplex virus (HSV) pathogenesis in mice differs based on availability of the principal entry receptors herpesvirus entry mediator (HVEM) and nectin-1 in a manner dependent upon route of inoculation. After intravaginal or intracranial inoculation of adult mice, nectin-1 is a major mediator of neurologic disease, while the absence of either receptor attenuates disease after ocular infection. We tested the importance of receptor availability and route of infection on disease in mouse models of neonatal HSV. We infected 7-day-old mice lacking neither or one principal HSV receptor or both principal HSV receptors with HSV-2 via a peripheral route (intranasal), via a systemic route (intraperitoneal), or by inoculation directly into the central nervous system (intracranial). Mortality, neurologic disease, and visceral dissemination of virus were significantly attenuated in nectin-1 knockout mice compared with HVEM knockout or wild-type mice after intranasal inoculation. Mice lacking both entry receptors (double-knockout mice) showed no evidence of disease after inoculation by any route. Nectin-1 knockout mice had delayed mortality after intraperitoneal inoculation relative to wild-type and HVEM knockout mice, but virus was able to spread to the brain and viscera in all genotypes except double-knockout mice. Unlike in adult mice, HVEM was sufficient to mediate disease in neonatal mice after direct intracranial inoculation, and the absence of HVEM delayed time to mortality relative to that of wild-type mice. Additionally, in wild-type neonatal mice inoculated intracranially, HSV antigen did not primarily colocalize with NeuN-positive neurons. Our results suggest that differences in receptor expression between adults and newborns may partially explain differences in susceptibility to HSV-2.
Japanese Encephalitis Virus Core Protein Inhibits Stress Granule Formation through an Interaction with Caprin-1 and Facilitates Viral Propagation
Authors: Katoh Hiroshi , Okamoto Toru , Fukuhara Takasuke , Kambara Hiroto , Morita Eiji , Mori Yoshio , Kamitani Wataru , Matsuura Yoshiharu
Published: October 2012

Stress granules (SGs) are cytoplasmic foci composed of stalled translation preinitiation complexes induced by environmental stress stimuli, including viral infection. Since viral propagation completely depends on the host translational machinery, many viruses have evolved to circumvent the induction of SGs or co-opt SG components. In this study, we found that expression of Japanese encephalitis virus (JEV) core protein inhibits SG formation. Caprin-1 was identified as a binding partner of the core protein by an affinity capture mass spectrometry analysis. Alanine scanning mutagenesis revealed that Lys
97
and Arg
98
in the α-helix of the JEV core protein play a crucial role in the interaction with Caprin-1. In cells infected with a mutant JEV in which Lys
97
and Arg
98
were replaced with alanines in the core protein, the inhibition of SG formation was abrogated, and viral propagation was impaired. Furthermore, the mutant JEV exhibited attenuated virulence in mice. These results suggest that the JEV core protein circumvents translational shutoff by inhibiting SG formation through an interaction with Caprin-1 and facilitates viral propagation
in vitro
and
in vivo
.
Reassortment between Two Serologically Unrelated Bluetongue Virus Strains Is Flexible and Can Involve any Genome Segment
Authors: Shaw Andrew E. , Ratinier Maxime , Nunes Sandro Filipe , Nomikou Kyriaki , Caporale Marco , Golder Matthew , Allan Kathryn , Hamers Claude , Hudelet Pascal , Zientara Stéphan , Breard Emmanuel , Mertens Peter , Palmarini Massimo
Published: October 2012

Coinfection of a cell by two different strains of a segmented virus can give rise to a “reassortant” with phenotypic characteristics that might differ from those of the parental strains. Bluetongue virus (BTV) is a double-stranded RNA (dsRNA) segmented virus and the cause of bluetongue, a major infectious disease of livestock. BTV exists as at least 26 different serotypes (BTV-1 to BTV-26). Prompted by the isolation of a field reassortant between BTV-1 and BTV-8, we systematically characterized the process of BTV reassortment. Using a reverse genetics approach, our study clearly indicates that any BTV-1 or BTV-8 genome segment can be rescued in the heterologous “backbone.” To assess phenotypic variation as a result of reassortment, we examined viral growth kinetics and plaque sizes inin vitroexperiments and virulence in an experimental mouse model of bluetongue disease. The monoreassortants generated had phenotypes that were very similar to those of the parental wild-type strains bothin vitroandin vivo. Using a forward genetics approach in cells coinfected with BTV-1 and BTV-8, we have shown that reassortants between BTV-1 and BTV-8 are generated very readily. After only four passages in cell culture, we could not detect wild-type BTV-1 or BTV-8 in any of 140 isolated viral plaques. In addition, most of the isolated reassortants contained heterologous VP2 and VP5 structural proteins, while only 17% had homologous VP2 and VP5 proteins. Our study has shown that reassortment in BTV is very flexible, and there is no fundamental barrier to the reassortment of any genome segment. Given the propensity of BTV to reassort, it is increasingly important to have an alternative classification system for orbiviruses.
A glossary of theories for understanding policymaking
Authors: Smith Katherine Elizabeth , Katikireddi Srinivasa Vittal
Published: October 2012

Public health practitioners and researchers often seek to influence public policies in order to improve population health and/or reduce health inequalities. However, these efforts frequently appear to be uninformed by the many empirically-based theories about policymaking that have been developed within political science. This glossary provides a brief overview of some of the most popular of these theories, describing how each: frames the policymaking process; portrays the relationships and influence of specific policy actors; and depicts the potential for policy change (or inertia). Examples of their application to public health are provided to help improve understanding of the material presented. Throughout the article, the implications of the different theories for public health researchers and advocates seeking to inform policy decisions are emphasised. The glossary aims to provide an accessible overview to key theories about policy and decision-making, with a view to supporting public health efforts to achieve healthier public policies.
Detection of Clostridium perfringens type C in pig herds following disease outbreak and subsequent vaccination
Authors: Schäfer K. , Wyder M. , Gobeli S. , Candi A. , Doherr M. G. , Zehnder B. , Zimmermann W. , Posthaus H.
Published: October 2012

Immunisation of sows using Clostridium perfringens type C toxoid vaccines is recommended to prevent necrotising enteritis (NE) on pig breeding farms. Absence of disease, however, oftentimes leads to the false assumption of pathogens being eradicated. The prevalence of C perfringens type C was determined by PCR in faecal samples of piglets and sows in three Swiss pig breeding farms two to four years after implementation of a vaccination programme following disease outbreaks. C perfringens type C could still be detected several years after an outbreak despite absence of NE. In‐herd prevalence of the pathogens varied significantly between the farms and was also lower compared with a farm which experienced a recent outbreak. In conclusion, C perfringens type C can be detected on once‐affected farms, even in the absence of NE for several years.
Ferrocement sandwich and hollow core panels for floor construction
Authors: Fahmy Ezzat H. , Shaheen Yousry B.I. , Abou Zeid Mohamed N. , Gaafar Hassan M.
Published: October 2012

This paper presents the results of a research work to develop ferrocement sandwich and hollow core panels for use as precast one way slab elements. Sandwich panels consisted of two thin ferrocement layers reinforced with steel wire mesh and a core of autoclaved aerated lightweight concrete bricks. The hollow core panels are made of the same ferrocement mortar matrix with three circular holes of 75 mm diameter running along the length of the specimen. A total of 15 sandwich panels and 12 hollow core panels were cast and tested under flexural loadings. The experimental results showed that high ultimate and service loads, crack resistance control, high ductility, and good energy absorption could be achieved by using the proposed panels. A theoretical model based on the ultimate strength method for reinforced concrete was developed to determine the ultimate moment and mode of failure of the panels. The theoretical and experimental results showed good agreement.
Summary of fossil vertebrate taxa named by Richard C. Fox, with an annotated list of taxa named between 1962 and 2012 and new photographs for non-mammalian therapsid and mammalian holotypes erected between 1968 and 1994
Authors: Scott Craig S. , Gardner James D.
Published: October 2012

Beginning in 1962 and extending to the present, Richard C. Fox and colleagues have named 87 species of fossil vertebrates (1 fish, 4 amphibians, 2 choristoderes, 12 lizards, 1 crocodile, 1 dinosaur, 2 “pelycosaurs”, 2 non-mammalian therapsids, and 62 mammals) and numerous new supraspecific taxa. Virtually all of these species continue to be accepted, although the higher-level assignments of several have been altered. The vast majority of the named species were founded on specimens, collected during the mid-1960s to early 2000s by field parties under Fox’s direction, from the Late Cretaceous (late Santonian to late Maastrichtian) and Paleocene of Alberta and Saskatchewan, Canada, and that are housed at the University of Alberta Laboratory for Vertebrate Paleontology. Here we present (i) an annotated list of all fossil vertebrate species named by Richard Fox between 1962 and 2012, (ii) updated information on the stratigraphic nomenclature and age estimates for the eight localities in Alberta that yielded holotypes for all the Cretaceous mammal species named by Richard Fox from that province, and (iii) new photographs for the holotypes of the one non-mammalian therapsid and 43 Late Cretaceous and Paleocene mammal species named by Richard Fox before 1995.
The Einstein–Maxwell-particle system in the York canonical basis of ADM tetrad gravity. Part 1. The equations of motion in arbitrary Schwinger time gauges 1This paper is one of three companion papers published in the same issue of Can. J. Phys.
Authors: Alba David , Lusanna Luca
Published: October 2012

We study the coupling of N charged scalar particles plus the electromagnetic field to Arnowitt–Deser–Misner (ADM) tetrad gravity and its canonical formulation in asymptotically Minkowskian space–times without super-translations. To regularize the self-energies, both the electric charge and the sign of the energy of the particles are Grassmann-valued. The introduction of the noncovariant radiation gauge allows reformulation of the theory in terms of transverse electromagnetic fields and to extract the generalization of the Coulomb interaction among the particles in the riemannian instantaneous 3-spaces of global noninertial frames, the only ones allowed by the equivalence principle. Then we make the canonical transformation to the York canonical basis, where there is a separation between the inertial (gauge) variables and the tidal ones inside the gravitational field and a special role of the eulerian observers associated with the 3+1 splitting of space–time. The Dirac hamiltonian is weakly equal to the weak ADM energy. The Hamilton equations in Schwinger time gauges are given explicitly. In the York basis they are naturally divided into four sets: (i) the contracted Bianchi identities; (ii) the equations for the inertial gauge variables; (iii) the equations for the tidal ones; and (iv) the equations for matter. Finally, we give the restriction of the Hamilton equations and of the constraints to the family of nonharmonic 3-orthogonal gauges, in which the instantaneous riemannian 3-spaces have a nonfixed trace 3K of the extrinsic curvature but a diagonal 3-metric. The inertial gauge variable 3K (the general-relativistic remnant of the freedom in the clock synchronization convention) gives rise to a negative kinetic term in the weak ADM energy vanishing only in the gauges with 3K = 0: is it relevant for dark energy and back-reaction? In the second paper will appear the linearization of the theory in these nonharmonic 3-orthogonal gauges to obtain hamiltonian post-minkowskian gravity (without post-newtonian approximations) with asymptotic Minkowski background, nonflat instantaneous 3-spaces and no post-newtonian expansion. This will allow the exploration of the inertial effects induced by the York time 3K in nonflat 3-spaces (they do not exist in newtonian gravity) and to check how well dark matter can be explained as an inertial aspect of Einstein’s general relativity: this will be done in a third paper on the post-minkowskian 2-body problem in the absence of the electromagnetic field and on its 0.5 post-newtonian limit.
ALMOST COMPLEX STRUCTURE ON PATH SPACE
Authors: KUMAR PRADIP
Published: October 2012

Let M be a complex manifold and let PM ≔ C∞([0, 1], M) be space of smooth paths over M. We prove that the induced almost complex structure on PM is weak integrable by extending the result of Indranil Biswas and Saikat Chatterjee of [Geometric structures on path spaces, Int. J. Geom. Meth. Mod. Phys.8(7) (2011) 1553–1569]. Further we prove that if M is smooth manifold with corner and N is any complex manifold then induced almost complex structure 𝔍 on Fréchet manifold C∞(M, N) is weak integrable.
SLANT RIEMANNIAN MAPS TO KÄHLER MANIFOLDS
Authors: ṢAHIN BAYRAM
Published: October 2012

We introduce slant Riemannian maps from Riemannian manifolds to almost Hermitian manifolds as a generalization of slant immersions, invariant Riemannian maps and anti-invariant Riemannian maps. We give examples, obtain characterizations and investigate the harmonicity of such maps. We also obtain necessary and sufficient conditions for slant Riemannian maps to be totally geodesic. Moreover, we relate the notion of slant Riemannian maps to the notion of pseudo horizontally weakly conformal (PHWC) maps which are useful for proving various complex-analytic properties of stable harmonic maps from complex projective space.
Extending the limits of natural photosynthesis and implications for technical light harvesting
Authors: Chen Min , Scheer Hugo
Published: October 2012

Photosynthetic organisms provide, directly or indirectly, the energy that sustains life on earth by harvesting light from the sun. The amount of light impinging on the surface of the earth vastly surpasses the energy needs of life including man. Harvesting the sun is, therefore, an option for a sustainable energy source: directly by improving biomass production, indirectly by coupling it to the production of hydrogen for fuel or, conceptually, by using photosynthetic strategies for technological solutions based on non-biological or hybrid materials. In this review, we summarize the various light climates on earth, the primary reactions responsible for light harvesting and transduction to chemical energy in photosynthesis, and the mechanisms of competitively adapting the photosynthetic apparatus to the ever-changing light conditions. The focus is on oxygenic photosynthesis, its adaptation to the various light-climates by specialized pigments and on the extension of its limits by the evolution of red-shifted chlorophylls. The implications for potential technical solutions are briefly discussed.
Fabrication of Nb-Doped TiO2 Transparent Conducting Films by Postdeposition Annealing under Nitrogen Atmosphere
Authors: Okazaki Sohei , Ohkubo Junpei , Nakao Shoichiro , Hirose Yasushi , Hitosugi Taro , Hasegawa Tetsuya
Published: October 2012

Here, we report that highly conductive polycrystalline anatase Nb-doped TiO2 (TNO) thin films can be prepared via crystallization of amorphous precursors under N2 atmosphere. An optimized TNO film on a glass substrate exhibited a low resistivity of 8.4 ×10-4 Ω cm and an absorbance of 6% at a wavelength of 460 nm. These transport and optical properties were comparable to those of TNO films fabricated by vacuum annealing. This demonstrates the potential of TNO as an electrode for GaN-based light-emitting diodes.
Comparative document summarization via discriminative sentence selection
Authors: Wang Dingding , Zhu Shenghuo , Li Tao , Gong Yihong
Published: October 2012

Given a collection of document groups, a natural question is to identify the differences among them. Although traditional document summarization techniques can summarize the content of the document groups one by one, there exists a great necessity to generate a summary of the differences among the document groups. In this article, we study a novel problem, that of summarizing the differences between document groups. A discriminative sentence selection method is proposed to extract the most discriminative sentences which represent the specific characteristics of each document group. Experiments and case studies on real-world data sets demonstrate the effectiveness of our proposed method.
Bullying
Authors: Brank Eve M. , Hoetger Lori A. , Hazen Katherine P.
Published: October 2012

The effects of bullying on the bully and the victim can be wide reaching, impacting schoolwork, familial and peer relationships, psychological well-being, and physical health. As such, schools work to implement different intervention and prevention programs. Additionally, a variety of both criminal and civil legal interventions have recently been used to prevent or punish bullying. Most US states have enacted antibullying legislation that prohibits bullying behaviors, but definitional issues that are present in the empirical research are also present in such statutes. For instance, some states focus only on physical forms of bullying or leave definitions entirely up to individual communities and schools. Bullying victims also have the option to bring civil suits for tortious acts related to the bullying; this review provides examples of the difficulties with bringing such cases.
PPARγ activation attenuates cold-induced upregulation of thyroid status and brown adipose tissue PGC-1α and D2
Authors: Festuccia William T. , Blanchard Pierre-Gilles , Oliveira Thiago B. , Magdalon Juliana , Paschoal Vivian A. , Richard Denis , Deshaies Yves
Published: October 2012

Here, we investigated whether pharmacological PPARγ activation modulates key early events in brown adipose tissue (BAT) recruitment induced by acute cold exposure with the aim of unraveling the interrelationships between sympathetic and PPARγ signaling. Sprague-Dawley rats treated or not with the PPARγ ligand rosiglitazone (15 mg·kg−1·day−1, 7 days) were kept at 23°C or exposed to cold (5°C) for 24 h and evaluated for BAT gene expression, sympathetic activity, thyroid status, and adrenergic signaling. Rosiglitazone did not affect the reduction in body weight gain and the increase in feed efficiency, V̇o2, and BAT sympathetic activity induced by 24-h cold exposure. Rosiglitazone strongly attenuated the increase in serum total and free T4 and T3 levels and BAT iodothyronine deiodinase type 2 (D2) and PGC-1α mRNA levels and potentiated the reduction in BAT thyroid hormone receptor (THR) β mRNA levels induced by cold. Administration of T3 to rosiglitazone-treated rats exacerbated the cold-induced increase in energy expenditure but did not restore a proper activation of D2 and PGC-1α, nor further increased uncoupling protein 1 expression. Regarding adrenergic signaling, rosiglitazone did not affect the changes in BAT cAMP content and PKA activity induced by cold. Rosiglitazone alone or in combination with cold increased CREB binding to DNA, but it markedly reduced the expression of one of its major coactivators, CREB binding protein. In conclusion, pharmacological PPARγ activation impairs short-term cold elicitation of BAT adrenergic and thyroid signaling, which may result in abnormal tissue recruitment and thermogenic activity.
Fluid dilution and efficiency of Na+transport in a mathematical model of a thick ascending limb cell
Authors: Nieves-González Aniel , Clausen Chris , Marcano Mariano , Layton Anita T. , Layton Harold E. , Moore Leon C.
Published: October 2012

Thick ascending limb (TAL) cells are capable of reducing tubular fluid Na+concentration to as low as ∼25 mM, and yet they are thought to transport Na+efficiently owing to passive paracellular Na+absorption. Transport efficiency in the TAL is of particular importance in the outer medulla where O2availability is limited by low blood flow. We used a mathematical model of a TAL cell to estimate the efficiency of Na+transport and to examine how tubular dilution and cell volume regulation influence transport efficiency. The TAL cell model represents 13 major solutes and the associated transporters and channels; model equations are based on mass conservation and electroneutrality constraints. We analyzed TAL transport in cells with conditions relevant to the inner stripe of the outer medulla, the cortico-medullary junction, and the distal cortical TAL. At each location Na+transport efficiency was computed as functions of changes in luminal NaCl concentration ([NaCl]), [K+], [NH4+], junctional Na+permeability, and apical K+permeability. Na+transport efficiency was calculated as the ratio of total net Na+transport to transcellular Na+transport. Transport efficiency is predicted to be highest at the cortico-medullary boundary where the transepithelial Na+gradient is the smallest. Transport efficiency is lowest in the cortex where luminal [NaCl] approaches static head.
Effects of cortical feedback on the spatial properties of relay cells in the lateral geniculate nucleus
Authors: Andolina Ian M. , Jones Helen E. , Sillito Adam M.
Published: October 2012

Feedback connections to early-level sensory neurons have been shown to affect many characteristics of their neural response. Because selectivity for stimulus size is a fundamental property of visual neurons, we examined the summation tuning and discretely mapped receptive field (RF) properties of cells in the lateral geniculate nucleus (LGN) both with and without feedback from visual cortex. Using extracellular recording in halothane-anesthetized cats, we used small luminance probes displaced in Cartesian coordinates to measure discrete response area, and optimal sinusoidal gratings of varying diameter to estimate preferred optimal summation size and level of center-surround antagonism. In conditions where most cortical feedback was pharmacologically removed, discretely mapped RF response areas showed an overall significant enlargement for the population compared with control conditions. A switch to increased levels of burst firing, spatially displaced from the RF center, suggested this was mediated by changes in excitatory-inhibitory balance across visual space. With the use of coextensive stimulation, there were overall highly significant increases in the optimal summation size and reduction of surround antagonism with removal of cortical feedback in the LGN. When fitted with a difference-of-Gaussian (DOG) model, changes in the center size, center amplitude, and surround amplitude parameters were most significantly related to the removal of cortical feedback. In summary, corticothalamic innervation of the visual thalamus can modify spatial summation properties in LGN relay cells, an effect most parsimoniously explained by changes in the excitatory-inhibitory balance.
Regulation of AMPA and NMDA receptor-mediated EPSPs in dendritic trees of thalamocortical cells
Authors: Lajeunesse Francis , Kröger Helmut , Timofeev Igor
Published: October 2012

Two main excitatory synapses are formed at the dendritic arbor of first-order nuclei thalamocortical (TC) neurons. Ascending sensory axons primarily establish contacts at large proximal dendrites, whereas descending corticothalamic fibers form synapses on thin distal dendrites. With the use of a multicomparment computational model based on fully reconstructed TC neurons from the ventroposterolateral nucleus of the cat, we compared local responses at the site of stimulation as well as somatic responses induced by both α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR)- and N-methyl-d-aspartate receptor (NMDAR)-mediated currents. We found that AMPAR-mediated responses, when synapses were located at proximal dendrites, induced a larger depolarization at the level of soma, whereas NMDAR-mediated responses were more efficient for synapses located at distal dendrites. The voltage transfer and transfer impedance were higher for NMDAR than for AMPAR activation at any location. For both types of synaptic current and for both input locations at the dendritic arbor, somatic responses were characterized by a low variability despite the large variability found in local responses in dendrites. The large neurons had overall smaller somatic responses than small neurons, but this relation was not found in local dendritic responses. We conclude that in TC cells, the dendritic location of small synaptic inputs does not play a major role in the amplitude of a somatic response, but the size of the neuron does. The variability of response amplitude between cells was much larger than the variability within cells. This suggests possible functional segregation of TC neurons of different size.
Clinical Implication of Adenosine Test at Repeat Atrial Fibrillation Ablation Procedure
Authors: Miyazaki Shinsuke , Kobori Atsushi , Komatsu Yuki , Kuwahara Taishi , Uchiyama Takashi , Kusa Shigeki , Taniguchi Hiroshi , Hachiya Hitoshi , Hirao Kenzo , Isobe Mitsuaki , Takahashi Atsushi , Iesaka Yoshito
Published: October 2012

Background—

Pulmonary vein reconnection after electrical isolation is commonly observed in the context of atrial fibrillation ablation and is associated with recurrent atrial tachyarrhythmias. Adenosine test was been performed to identify acute dormant conduction immediately after pulmonary vein isolation at index procedure. However, the utility of adenosine test at repeat procedure has not been reported.

Methods and Results—

We report 5 paroxysmal atrial fibrillation cases without any structural heart disease in which dormant thoracic vein conduction was associated with recurrent atrial tachyarrhythmias. All patients had undergone circumferential ipsilateral pulmonary vein isolation at the index procedure. Superior vena cava isolation was performed if superior vena cava–triggered atrial fibrillation was identified. At the index procedure, adenosine test did not provoke venous reconduction. At the repeat procedure, adenosine provoked clinical arrhythmia in 4 out of 5 cases after transient reconnection between culprit thoracic vein and atrium despite absence of reconnection at the start of the procedure. After the elimination of the dormant conduction gaps, all patients were free from recurrent arrhythmia.

Conclusions—

Adenosine provokes dormant thoracic vein conduction associated with the late recurrence of atrial tachyarrhythmias after previous thoracic vein isolation. Thus, adenosine provocation test can specifically help identify and target the cause of recurrent atrial arrhythmia.
Endothelial Cells Derived From Nuclear Reprogramming
Authors: Wong Wing Tak , Huang Ngan F. , Botham Crystal M. , Sayed Nazish , Cooke John P.
Published: October 2012

The endothelium plays a pivotal role in vascular homeostasis, regulating the tone of the vascular wall, and its interaction with circulating blood elements. Alterations in endothelial functions facilitate the infiltration of inflammatory cells and permit vascular smooth muscle proliferation and platelet aggregation. Therefore, endothelial dysfunction is an early event in disease processes including atherosclerosis, and because of its critical role in vascular health, the endothelium is worthy of the intense focus it has received. However, there are limitations to studying human endothelial function in vivo, or human vascular segments ex vivo. Thus, methods for endothelial cell (EC) culture have been developed and refined. Recently, methods to derive ECs from pluripotent cells have extended the scientific range of human EC studies. Pluripotent stem cells may be generated, expanded, and then differentiated into ECs for in vitro studies. Constructs for molecular imaging can also be employed to facilitate tracking these cells in vivo. Furthermore, one can generate patient-specific ECs to study the effects of genetic or epigenetic alterations on endothelial behavior. Finally, there is the opportunity to apply these cells for vascular therapy. This review focuses on the generation of ECs from stem cells; their characterization by genetic, histological, and functional studies; and their translational applications.
Protein Kolam: An Artistic Rendition of Molecular Structure Data
Authors: Balaji S. , Neela S.
Published: October 2012

Any detailed discussion of protein function inevitably involves protein structure. In this article, a visual representation intended to allow the artistic interpretation of protein structure data is presented. The authors have simplified the representation of proteins through the use of the traditional South Indian folk art kolam. This artistic representation presents an interesting means for understanding complicated protein folds. The work presented here may also provide a basis for the study of the topology, similarity and assembly of biological macromolecules.