bluuebunny/crossref_metadata_2025 huggingface dataset:
Invasive Harlequin Ladybird Carries Biological Weapons Against Native Competitors
Authors: Vilcinskas Andreas , Stoecker Kilian , Schmidtberg Henrike , Röhrich Christian R. , Vogel Heiko
Published: May 2013

Surprise Attack

Humans conduct the largest ecological experiment ever by continually moving species between continents. For example, the harlequin ladybird beetle, native to Asia, has become highly invasive in many regions after being introduced for biological control, but we do not understand why this species should so readily outcompete native ladybirds.

Vilcinskas
et al.

(p.
862
; see the Perspective by

Reynolds

) show that harlequin beetles have parasitic microsporidia within their hemolymph, which are fatal to other ladybird beetles that prey on harlequin beetle eggs and larvae. Harlequin beetles thus have an innate advantage over species that are otherwise equivalent in their abilities, but this sort of competitive advantage can be hard to spot.
A Role for
Drosophila
ATX2 in Activation of PER Translation and Circadian Behavior
Authors: Zhang Yong , Ling Jinli , Yuan Chunyan , Dubruille Raphaëlle , Emery Patrick
Published: May 2013

ATAXIN Clock

Although core components of circadian clocks in flies and mammals are transcriptional circuits, recent evidence indicates posttranscriptional regulation of the clock occurs. Studies from
Lim and Allada
(p.
875
) and

Zhang
et al.

(p.
879
) converge to show that the protein ATAXIN-2, associated with neurodegenerative diseases in humans, is a regulator of translation required for normal clock function in pacemaker neurons and for daily rhythms of behavior. ATAXIN is an RNA-binding protein and cooperates in the accumulation of the Per (Period) protein, a core transcriptional regulatory component of the clock.
Impact of Shale Gas Development on Regional Water Quality
Authors: Vidic R. D. , Brantley S. L. , Vandenbossche J. M. , Yoxtheimer D. , Abad J. D.
Published: May 2013

Fracturing Hydrology?

Hydraulic fracturing, widely known as "fracking," is a relatively inexpensive way to tap into what were previously inaccessible natural gas resources.

Vidic
et al.

(p.
826
) review the current status of shale gas development and discuss the possible threats to water resources. In one of the hotbeds of fracking activity, the Marcellus Shale in the eastern United States, there is little evidence that additives have directly entered groundwater supplies, but the risk remains. Ensuring access to monitoring data is an important first step toward addressing any public and environmental health concerns.
Our Viral Inheritance
Authors: Weiss Robin A. , Stoye Jonathan P.
Published: May 2013

Viruses incorporated into vertebrate genomes may reemerge after long periods of dormancy to play a range of biological roles in their host.
"Fascinating Little Whatzits"
The Great Fossil Enigma
The Search for the Conodont Animal

by Simon J. Knell

Indiana University Press, Bloomington, IN, 2013. 437 pp. $45. ISBN 9780253006042.
Authors: Donoghue Philip
Published: May 2013

Charting how researchers have conceptualized the conodont animal, Knell offers a fresh perspective on the challenges of understanding unusual extinct taxa.
The Life and Times of a Living Fossil
Ginkgo
The Tree That Time Forgot

by Peter Crane

Yale University Press, New Haven, CT, 2013. 404 pp. $40. ISBN 9780300187519.
Authors: McElwain J. C.
Published: May 2013

In this "biography" of ginkgos, Crane interweaves aspects of the tree's biology and evolution with stories of people who have helped establish the species in cities around the globe.
Insulin Finds Its Niche
Authors: Cheetham Seth W. , Brand Andrea H.
Published: May 2013

Localized insulin signaling allows organ-specific rather than organism-level responses to the environmental conditions.
Immunity and Invasive Success
Authors: Reynolds Stuart E.
Published: May 2013

The Asian harlequin ladybird has successfully invaded ecosystems around the world with the help of a pathogen that it carries.

[Also see Report by

Vilcinskas
et al.

]
(Poly)Combing the Pediatric Cancer Genome for Answers
Authors: Morgan Marc Alard , Shilatifard Ali
Published: May 2013

Misregulation of the pattern and localization of histone modifications may result in cancer development.

[Also see Report by

Lewis
et al.

]
Impact Factor Distortions
Authors: Alberts Bruce
Published: May 2013

This Editorial coincides with the release of the
San Francisco declaration on research Assessment
(DORA), the outcome of a gathering of concerned scientists at the December 2012 meeting of the American Society for Cell Biology.
*
To correct distortions in the evaluation of scientific research, DORA aims to stop the use of the "journal impact factor" in judging an individual scientist's work. The
Declaration
states that the impact factor must not be used as "a surrogate measure of the quality of individual research articles, to assess an individual scientist's contributions, or in hiring, promotion, or funding decisions." DORA also provides a list of specific actions, targeted at improving the way scientific publications are assessed, to be taken by funding agencies, institutions, publishers, researchers, and the organizations that supply metrics. These recommendations have thus far been endorsed by more than 150 leading scientists and 75 scientific organizations, including the American Association for the Advancement of Science (the publisher of
Science
). Here are some reasons why:
Melting Glaciers, Not Just Ice Sheets, Stoking Sea-Level Rise
Authors: Kerr Richard A.
Published: May 2013

A new study says that although field measurements were painting an accurate picture of the few glaciers being monitored, they were not representative of the world's glaciers.
More Genomes From Denisova Cave Show Mixing of Early Human Groups
Authors: Pennisi Elizabeth
Published: May 2013

Analyses of three fossil samples using a powerful new method paint a complex picture of mingling among different ancient human groups.
Lawmakers Await NSF's Response to Query About Grants
Authors: Mervis Jeffrey
Published: May 2013

NSF officials must weigh factors such as the preservation of reviewer confidentiality in responding to Representative Lamar Smith's request for the agency to justify five recent research grants.
From Quarry to Temple
Authors: Pringle Heather
Published: May 2013

Two thousand years after the Kizilburun shipwreck, excavating archaeologists have figured out exactly where it came from, where it was headed, and why.
Following the Flavor
Authors: Kupferschmidt Kai
Published: May 2013

Scientists are beginning to unravel why we love some types of food and hate others. It's a vastly more complex topic than they once thought.
A Floating Lab Explores the Fringes of Science and Gastronomy
Authors: Kupferschmidt Kai
Published: May 2013

Ben Reade and the Nordic Food Lab are part of a movement known as molecular gastronomy that started in the 1990s as a project to understand how ingredients are transformed during cooking.
HLA-B*44 Is Associated with a Lower Viral Set Point and Slow CD4 Decline in a Cohort of Chinese Homosexual Men Acutely Infected with HIV-1
Authors: Zhang Xin , Huang XiaoJie , Xia Wei , Li WeiHua , Zhang Tong , Wu Hao , Xu XiaoNing , Yan HuiPing
Published: May 2013

HLA class I alleles have been shown to have differential impacts on the viral load and the outcome of HIV-1 disease progression. In this study, HLA class I types from residents of China with acute HIV-1 infection, diagnosed between 2006 and 2011, were identified and the association between expression of individual HLA alleles and the level of the set point viral load was analyzed. A lower level of set point viral load was found to be associated with the Bw4 homozygote on HLA-B alleles. B*44 and B*57 alleles have also been found to be associated with lower set point viral load. The set point viral load of B*44-positive individuals homozygous for Bw4 was significantly lower than that of B*44-negative individuals homozygous for Bw4 (P= 0.030). The CD4 count declined to <350 in fewer B*44-positive individuals than B*44-negative individuals (X2= 7.295,P= 0.026). B*44-positive individuals had a lower magnitude of p24 pool-specific T cell responses than B*44-negative individuals homozygous for Bw4, though this was not statistically significant. The p24 pool-specific T cell responses were also inversely correlated with lower viral load (rs= −0.88,P= 0.033). Six peptides within p24 were recognized to induce the specific-T cell response in B*44-positive individuals, and the peptide breadth of response was same as that in B*44-negative individuals homozygous for Bw4, but the median magnitude of specific-T cell responses to the recognized peptides in B*44-positive individuals was lower than that in B*44-negative individuals homozygous for Bw4 (P= 0.049). These findings imply that weak p24-specific CD8+T cell responses might play an important role in the control of HIV viremia in B*44 allele-positive individuals. Such studies might contribute to the development of future therapeutic strategies that take into account the genetic background of the patients.
Antimicrobial Susceptibility among Gram-Positive Organisms Collected from Pediatric Patients Globally between 2004 and 2011: Results from the Tigecycline Evaluation and Surveillance Trial
Authors: Brandon Michael , Dowzicky Michael J.
Published: May 2013

The Tigecycline Evaluation and Surveillance Trial (TEST) was designed to monitor global longitudinal changes in bacterial susceptibility to a panel of antimicrobial agents, including tigecycline. In this study, we examine susceptibility among Gram-positive isolates collected from pediatric patients globally between 2004 and 2011. A total of 9,422 Gram-positive isolates were contributed by 1,255 centers, predominantly from Europe and North America. One-third of
Staphylococcus aureus
isolates were methicillin resistant, peaking in prevalence in 2007. All
S. aureus
isolates (
n
= 3,614) were susceptible to linezolid, tigecycline, and vancomycin; minocycline, imipenem, and meropenem were also highly active (>92% susceptibility). Ampicillin and penicillin susceptibility increased significantly during the study period (
P
< 0.0001 for both).
Streptococcus pneumoniae
isolates (
n
= 3,373) were highly susceptible to vancomycin (100%), linezolid (>99%), and levofloxacin and tigecycline (both >96%); imipenem susceptibility was low (32%) in Africa while minocycline susceptibility was low in Asia-Pacific Rim (38%). Penicillin resistance occurred in one-fifth of all
S. pneumoniae
isolates, with penicillin susceptibility ranging from 14% in Africa to 65% in Europe.
Streptococcus agalactiae
isolates (
n
= 1,056) were highly susceptible to most antimicrobials, although only 16% were susceptible to minocycline.
Enterococcus faecalis
isolates (
n
= 1,112) were highly susceptible (>97%) to ampicillin, linezolid, penicillin, tigecycline, and vancomycin globally, but only 34% were minocycline susceptible; minocycline susceptibility decreased significantly from 2004 to 2011 (
P
< 0.001). Tigecycline and linezolid were highly active against
Enterococcus faecium
(
n
= 267) globally (100% and 98% susceptible, respectively). Tigecycline and linezolid were highly active against Gram-positive pathogens from pediatric patients in TEST 2004 to 2011, with vancomycin and the carbapenems performing well against most pathogens.
Detection of Mycobacterium tuberculosis in Blood by Use of the Xpert MTB/RIF Assay
Authors: Banada Padmapriya P. , Koshy Ranie , Alland David
Published: May 2013

We have developed a novel blood lysis-centrifugation approach for highly sensitive
Mycobacterium tuberculosis
detection in large volumes of blood with the Xpert MTB/RIF assay. One through 20 ml of blood was spiked with 0.25 to 10 CFU/ml of the
M. tuberculosis
surrogate
M. bovis
BCG. Multiple replicates of each sample were processed by a new lysis-centrifugation method and tested with the Xpert MTB/RIF assay. The assay was very sensitive with increased blood volumes. In the 20-ml samples, BCG was detected in blood spiked with 10, 5, 1, and 0.25 CFU/ml 100, 100, 83, and 57% of the time, respectively, compared to 100, 66, 18, and 18%, of the time, respectively, in 1-ml blood samples. Assay sensitivity was influenced by the type of anticoagulant used, with acid-citrate-dextrose solution B (ACD-B) providing the best results. A limit of detection of 10 CFU/ml was established with BCG spiked into ACD-B-treated blood, and 92, 36, and 33% of the samples with 5, 1, and 0.5 CFU/ml, respectively, were assay positive. The lysis buffer was stable both at room temperature and at 4°C for 2 months. The assay was tested with blood stored for 8 days without a change in sensitivity as measured by cycle threshold. This new assay format extends the capability of the Xpert MTB/RIF test, enabling up to 20 ml of blood to be tested rapidly for the presence of
M. tuberculosis
. This approach may be a useful method to detect extrapulmonary tuberculosis and the risk of death in immunocompromised patients.
Identification of Medically Relevant Species of Arthroconidial Yeasts by Use of Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry
Authors: Kolecka Anna , Khayhan Kantarawee , Groenewald Marizeth , Theelen Bart , Arabatzis Michael , Velegraki Aristea , Kostrzewa Markus , Mares Mihai , Taj-Aldeen Saad J. , Boekhout Teun
Published: May 2013

Matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS) was used for an extensive identification study of arthroconidial yeasts, using 85 reference strains from the CBS-KNAW yeast collection and 134 clinical isolates collected from medical centers in Qatar, Greece, and Romania. The test set included 72 strains of ascomycetous yeasts (Galactomyces,Geotrichum,Saprochaete, andMagnusiomycesspp.) and 147 strains of basidiomycetous yeasts (TrichosporonandGuehomycesspp.). With minimal preparation time, MALDI-TOF MS proved to be an excellent diagnostic tool that provided reliable identification of most (98%) of the tested strains to the species level, with good discriminatory power. The majority of strains were correctly identified at the species level with good scores (>2.0) and seven of the tested strains with log score values between 1.7 and 2.0. The MALDI-TOF MS results obtained were consistent with validated internal transcribed spacer (ITS) and/or large subunit (LSU) ribosomal DNA sequencing results. Expanding the mass spectrum database by increasing the number of reference strains for closely related species, including those of nonclinical origin, should enhance the usefulness of MALDI-TOF MS-based diagnostic analysis of these arthroconidial fungi in medical and other laboratories.
Development and Evaluation of a Real-Time PCR Assay for Detection of Pneumocystis jirovecii on the Fully Automated BD MAX Platform
Authors: Dalpke Alexander H. , Hofko Marjeta , Zimmermann Stefan
Published: May 2013

Pneumocystis jirovecii
is an opportunistic pathogen in immunocompromised and AIDS patients. Detection by quantitative PCR is faster and more sensitive than microscopic diagnosis yet requires specific infrastructure. We adapted a real-time PCR amplifying the major surface glycoprotein (MSG) target from
Pneumocystis jirovecii
for use on the new BD MAX platform. The assay allowed fully automated DNA extraction and multiplex real-time PCR. The BD MAX assay was evaluated against manual DNA extraction and conventional real-time PCR. The BD MAX was used in the research mode running a multiplex PCR (MSG, internal control, and sample process control). The assay had a detection limit of 10 copies of an MSG-encoding plasmid per PCR that equated to 500 copies/ml in respiratory specimens. We observed accurate quantification of MSG targets over a 7- to 8-log range. Prealiquoting and sealing of the complete PCR reagents in conical tubes allowed easy and convenient handling of the BD MAX PCR. In a retrospective analysis of 54 positive samples, the BD MAX assay showed good quantitative correlation with the reference PCR method (
R
2
= 0.82). Cross-contamination was not observed. Prospectively, 278 respiratory samples were analyzed by both molecular assays. The positivity rate overall was 18.3%. The BD MAX assay identified 46 positive samples, compared to 40 by the reference PCR. The BD MAX assay required liquefaction of highly viscous samples with dithiothreitol as the only manual step, thus offering advantages for timely availability of molecular-based detection assays.
Long-Term Stability of Human Genomic and Human Papillomavirus DNA Stored in BD SurePath and Hologic PreservCyt Liquid-Based Cytology Media
Authors: Agreda Patricia M. , Beitman Gerard H. , Gutierrez Erin C. , Harris James M. , Koch Kristopher R. , LaViers William D. , Leitch Sharon V. , Maus Courtney E. , McMillian Ray A. , Nussbaumer William A. , Palmer Marcus L. R. , Porter Michael J. , Richart Gregory A. , Schwab Ryan J. , Vaughan Laurence M.
Published: May 2013

We evaluated the effect of storage at 2 to 8°C on the stability of human genomic and human papillomavirus (HPV) DNA stored in BD SurePath and Hologic PreservCyt liquid-based cytology media. DNA retained the ability to be extracted and PCR amplified for more than 2.5 years in both medium types. Prior inability to detect DNA in archived specimens may have been due to failure of the extraction method to isolate DNA from fixed cells.
Comparison of Restriction Enzymes for Pulsed-Field Gel Electrophoresis Typing of Moraxella catarrhalis
Authors: Marti Sara , Puig Carmen , Domenech Arnau , Liñares Josefina , Ardanuy Carmen
Published: May 2013

NotI, the most prevalent restriction enzyme used for typing
Moraxella catarrhalis
, failed to digest genomic DNA from respiratory samples. An improved pulsed-field gel electrophoresis (PFGE) methodology determined SpeI as the best choice for typing this bacterial species, with a good restriction of clinical samples and a good clustering correlation with NotI.
The Role of Virulence in
In Vivo
Superinfection Fitness of the Vertebrate RNA Virus Infectious Hematopoietic Necrosis Virus
Authors: Kell Alison M. , Wargo Andrew R. , Kurath Gael
Published: May 2013

We have developed a novel
in vivo
superinfection fitness assay to examine superinfection dynamics and the role of virulence in superinfection fitness. This assay involves controlled, sequential infections of a natural vertebrate host,
Oncorhynchus mykiss
(rainbow trout), with variants of a coevolved viral pathogen, infectious hematopoietic necrosis virus (IHNV). Intervals between infections ranged from 12 h to 7 days, and both frequency of superinfection and viral replication levels were examined. Using virus genotype pairs of equal and unequal virulence, we observed that superinfection generally occurred with decreasing frequency as the interval between exposures to each genotype increased. For both the equal-virulence and unequal-virulence genotype pairs, the frequency of superinfection in most cases was the same regardless of which genotype was used in the primary exposure. The ability to replicate in the context of superinfection also did not differ between the genotypes of equal or unequal virulence tested here. For both genotype pairs, the mean viral load of the secondary virus was significantly reduced in superinfection while primary virus replication was unaffected. Our results demonstrate, for the two genotype pairs examined, that superinfection restriction does occur for IHNV and that higher virulence did not correlate with a significant difference in superinfection fitness. To our knowledge, this is the first assay to examine the role of virulence of an RNA virus in determining superinfection fitness dynamics within a natural vertebrate host.
Upregulation of CHOP/GADD153 during Coronavirus Infectious Bronchitis Virus Infection Modulates Apoptosis by Restricting Activation of the Extracellular Signal-Regulated Kinase Pathway
Authors: Liao Ying , Fung To Sing , Huang Mei , Fang Shou Guo , Zhong Yanxin , Liu Ding Xiang
Published: May 2013

Induction of the unfolded protein response (UPR) is an adaptive cellular response to endoplasmic reticulum (ER) stress that allows a cell to reestablish ER homeostasis. However, under severe and persistent ER stress, prolonged UPR may activate unique pathways that lead to cell death. In this study, we investigated the activation of the protein kinase R-like ER kinase (PERK) pathway of UPR in cells infected with the coronavirus infectious bronchitis virus (IBV) and its relationship with IBV-induced apoptosis. The results showed moderate induction of PERK phosphorylation in IBV-infected cells. Meanwhile, activating transcription factor 4 (ATF4) was upregulated at the protein level in the infected cells, resulting in the induction in
trans
of the transcription factor ATF3 and the proapoptotic growth arrest and DNA damage-inducible protein GADD153. Knockdown of PERK by small interfering RNA (siRNA) suppressed the activation of GADD153 and the IBV-induced apoptosis. Interestingly, knockdown of protein kinase R (PKR) by siRNA and inhibition of the PKR kinase activity by 2-aminopurine (2-AP) also reduced the IBV-induced upregulation of GADD153 and apoptosis induction. In GADD153-knockdown cells, IBV-induced apoptosis was suppressed and virus replication inhibited, revealing a key role of GADD153 in IBV-induced cell death and virus replication. Analysis of the pathways downstream of GADD153 revealed much more activation of the extracellular signal-related kinase (ERK) pathway in GADD153-knockdown cells during IBV infection, indicating that GADD153 may modulate apoptosis through suppression of the pathway. This study provides solid evidence that induction of GADD153 by PERK and PKR plays an important regulatory role in the apoptotic process triggered by IBV infection.
HIV Populations Are Large and Accumulate High Genetic Diversity in a Nonlinear Fashion
Authors: Maldarelli Frank , Kearney Mary , Palmer Sarah , Stephens Robert , Mican JoAnn , Polis Michael A. , Davey Richard T. , Kovacs Joseph , Shao Wei , Rock-Kress Diane , Metcalf Julia A. , Rehm Catherine , Greer Sarah E. , Lucey Daniel L. , Danley Kristen , Alter Harvey , Mellors John W. , Coffin John M.
Published: May 2013

HIV infection is characterized by rapid and error-prone viral replication resulting in genetically diverse virus populations. The rate of accumulation of diversity and the mechanisms involved are under intense study to provide useful information to understand immune evasion and the development of drug resistance. To characterize the development of viral diversity after infection, we carried out an in-depth analysis of single genome sequences of HIVpro-polto assess diversity and divergence and to estimate replicating population sizes in a group of treatment-naive HIV-infected individuals sampled at single (n= 22) or multiple, longitudinal (n= 11) time points. Analysis of single genome sequences revealed nonlinear accumulation of sequence diversity during the course of infection. Diversity accumulated in recently infected individuals at rates 30-fold higher than in patients with chronic infection. Accumulation of synonymous changes accounted for most of the diversity during chronic infection. Accumulation of diversity resulted in population shifts, but the rates of change were low relative to estimated replication cycle times, consistent with relatively large population sizes. Analysis of changes in allele frequencies revealed effective population sizes that are substantially higher than previous estimates of approximately 1,000 infectious particles/infected individual. Taken together, these observations indicate that HIV populations are large, diverse, and slow to change in chronic infection and that the emergence of new mutations, including drug resistance mutations, is governed by both selection forces and drift.
HACEK-induced endocarditis
Authors: Wassef Nancy , Rizkalla Essam , Shaukat Naeem , Sluka Martin
Published: May 2013

A 61-year-old patient with diabetes had a bio-prosthetic aortic valve replacement 3 years before admission. He complained of lethargy, night sweats, decreased appetite and erratic blood glucose with no weight loss. He had splinter haemorrhage and a systolic ejection murmur at the aortic area. Chest and abdominal examination revealed no abnormality. The erythrocyte sedimentation rate and C reactive protein were raised. He had several sets of blood cultures and he was started on empirical vancomycin, rifampicin and gentamicin. Transthoracic echocardiography showed vegetation on the base of the anterior mitral leaflet, which was confirmed by a trans-oesophageal echocardiography. Blood culture was positive forHaemophilus aphrophilus, and he was started on ceftriaxone for 6 weeks instead of vancomycin and rifampicin and continued gentamicin for 2 weeks. Follow-up echocardiography showed no evidence of vegetations. The patient recovered completely and he was discharged home.
Conservative management of a ruptured mycotic aneurysm
Authors: Lodge Freya , Conway Nerys , Waterfield Nick
Published: May 2013

Mycotic aneurysms are a well-recognised complication of infective endocarditis. In contrast to many sequelae of endocarditis, they can present late in the course of the disease, despite adequate treatment. We discuss the case of an 82-year-old patient who was successfully treated forEnterococcus faecalisendocarditis, but presented late with a hypotensive collapse. CT imaging demonstrated a ruptured mycotic aneurysm. He underwent laparotomy, but the decision was made to treat conservatively to protect the vascular supply to the bowel. The patient subsequently made a full recovery.
Aceclofenac-induced acute tubulointerstitial nephritis in a patient with diabetes
Authors: Gupta Monica , Cruz Sanjay D , Nada Ritambhara , Aggarwal Purnima
Published: May 2013

We describe a case of a 40-year-old lady diabetic and hypertensive, who presented with increasing fatigue and decreased physical endurance attributable to deterioration in renal function. The renal biopsy revealed drug-induced acute tubulointerstitial nephritis and the chronology of the events suggested the aetiology to be a recent intake of aceclofenac for knee pain. The patient improved with oral corticosteroids and the renal functions returned to baseline in 3 weeks. We did not come across a case of aceclofenac-induced acute tubulointerstitial nephritis on extensive electronic search of literature. This is probably the first case report of acute tubulointerstitial nephritis associated with the use of aceclofenac, a newer potent non-steroidal anti-inflammatory drug.
Aortic valve tethering: embryonic remnant of a common origin?
Authors: Alvarez-Acosta Luis , Soriano-Vela Estanislao , Facenda-Lorenzo Maria , Farrais-Villalba Marcos
Published: May 2013

A 14-year-old asymptomatic girl without relevant medical history was referred to our department for heart murmur evaluation. The echocardiogram showed cardiac chambers with normal size and function. Noteworthy was the presence of an apparently fibrous tissue joining the ventricular surfaces of the aortic non-coronary and right coronary leaflets with the anterior mitral leaflet. Both valves were slightly thickened and there was a mild anterior mitral valve ‘billowing’ causing an eccentric mild-to-moderate regurgitant jet. During systole, tethering of this tissue caused the incomplete opening of both mentioned aortic leaflets, causing a turbulent flow with no significant gradient across the valve. During diastole, moderate eccentric aortic regurgitation jet was noted, probably related to incomplete coaptation at the insertion point of this anomalous tissue. We speculate that this finding may represent the remnant of some tissue during heart development that abnormally persisted in this young lady.
Balling gun‐induced trauma in cattle: clinical presentation, diagnosis and prevention
Authors: Mann S. , Nuss K. A. , Feist M. , Weber B. K. , Zoller D. K. , Metzner M.
Published: May 2013

Pharyngeal trauma in cattle can occur during the administration of oral medication using a balling gun. The number of cases of severe complications due to bolus application that have been referred to our hospital has increased from nil between 1996 and 2008 to three or four per year. In our experience, reports by bovine veterinarians of patients with severe and often fatal pharyngeal trauma, which were not referred to the clinic, have become more common in recent years as well. The incidence of this complication is likely to be higher than this number of referrals suggests. Diagnosis without the help of imaging techniques, such as radiography and endoscopy, may be difficult, especially in cases where exploration of the pharynx cannot be carried out, or is unable to confirm the absence or presence of a lesion. Prognosis is often poor in cases where perforation has been confirmed. Boluses are increasingly administered by the owners or farm personnel without the supervision of a veterinarian. In order to prevent losses due to balling gun‐induced injuries, the veterinarian plays a crucial role in giving advice to his clients. Five cases of cattle suffering from varying degrees of balling gun‐induced trauma are presented, and consideration is given to incorrect application techniques.
Clinorotation enhances autophagy in vascular endothelial cells
Authors: Wang Yong-Chun , Lu Dong-Yuan , Shi Fei , Zhang Shu , Yang Chang-Bin , Wang Bing , Cao Xin-Sheng , Du Ting-Yuan , Gao Yuan , Zhao Jiang-Dong , Sun Xi-Qing
Published: May 2013

Individuals exposed to extended periods of spaceflight or prolonged 6° head-down-tilt bed rest often suffer from health hazards represented by cardiovascular deconditioning. Many studies have reported that alterations in vascular endothelial cells contribute to cardiovascular dysfunction induced by microgravity. Autophagy, a lysosomal degradation pathway, serves an adaptive role for survival, differentiation, and development in cellular homeostasis, and can be triggered by various environmental stimuli. However, whether autophagy can be induced in endothelial cells by real or simulated microgravity remains to be determined. This study was designed to investigate the effects of simulated microgravity on the activation of autophagy in human umbilical vein endothelial cells (HUVECs). We report here that clinorotation, a simulated model of microgravity, enhances autophagosome formation, increases LC3 and beclin-1 expression, and promotes the conversion of LC3-I to LC3-II in HUVECs. These results demonstrate that simulated microgravity for 48 h activates autophagy of vascular endothelial cells.
$B^0\hbox{--}\bar B^0$ MIXING WITH THE CONSTRAINT OF A 125 GeV HIGGS
Authors: SUN FEI , FENG TAI-FU , ZHAO SHU-MIN , GAO TIE-JUN , KOU LI-NA , SUN KE-SHENG , HU YING
Published: May 2013

Considering the constraints from the current experiment results, we analyze [Formula: see text] mixing with a Higgs boson around 125 GeV, and discuss the influence of MA, tanβ to the mhand ΔmBin the Minimal Supersymmetric Standard Model (MSSM). We find these constraints have a strong impact to the parameters of MAand tanβ, they almost exclude the small MAand large tanβ, to have a obvious correction to the mass difference ΔmBwe argue that the MAshould not too large, it is possible to observe the MAboson with a mass 300 ~ 400 GeV in the future.
TACHYONIC BRANEWORLD INFLATION AND OBSERVATIONS
Authors: ZARROUKI R. , SAKHI Z. , BENNAI M.
Published: May 2013

We study various tachyonic inflationary spectrum perturbations in the context of the Randall–Sundrum type-2 braneworld model [L. Randall and R. Sundrum, Phys. Rev. Lett.83, 3370 (1999); Phys. Rev. Lett.83, 4690 (1999)]. We consider, in particular, the inverse power law potential [Formula: see text] of the tachyonic field in the high-energy and slow-roll approximations using the recent astronomical observations.
FIRST PRINCIPLES STUDY ON IRON PNICTIDE SUPERCONDUCTOR Ca0.88Pr0.12Fe2As2
Authors: MIAO RENDE , CAI DAN , YANG JUN , JIANG MIN , FAN CHUNHUI , LIU CUICUI , WU FANGPING , MA SHUYUN
Published: May 2013

The electronic structure, lattice dynamics, and electron–phonon (e–ph) coupling constant λ for the superconducting Ca 0.88 Pr 0.12 Fe 2 As 2 are obtained by first principles calculations using norm-conserving pseudopotentials within virtual-crystal approximation treatment. The obtained λ for Ca 0.88 Pr 0.12 Fe 2 As 2 is 0.45. Combined with the e–ph coupling constants λ for the superconducting CaFe 2 As 1.925 P 0.075 and vicinity of collapsed tetragonal phase of CaFe 2 As 2, we show that although the obtained λ for them cannot account for the high superconducting transition temperatures TC, they are a factor of two larger than that estimated in early calculations using the ultrasoft pseudopotentials for that of vicinity of collapsed tetragonal phase of CaFe 2 As 2. We confirm that superconductivity in CaFe 2 As 2 is not primarily phonon mediated. Nevertheless, the e–ph interactions are strong enough to be not negligible to investigate the superconductivity.
LOCALITY AND GLOBALITY DISCRIMINANT FEATURE AND ITS APPLICATION IN HYPERSPECTRAL IMAGE CLASSIFICATION
Authors: HUANG HONG , FENG HAILIANG
Published: May 2013

Feature selection has attracted a huge amount of interest in both research and application communities of hyperspectral image (HSI) classification. Generally, supervised feature selection methods are superior to unsupervised ones without label information. However, in classification of HSI, the labeled samples are often difficult, expensive or time-consuming to obtain. In this paper, we proposed a novel semi-supervised feature selection method, called Locality and Globality Discriminant Feature (LGDF), for HSI classification. This method combines Fisher's criteria and Graph Laplacian, which makes full use of both labeled and unlabeled data points to discover both manifold and discriminant structure in HSI data. In the proposed method, an optimal subset of features is identified if at this subset neighbor points or points sharing the same label are close to each other, while non-neighbor points or points with different labels are far away from each other. Experimental results on Washington DC Mall and AVIRIS Indian Pines hyperspectral datasets demonstrate the effectiveness of the proposed method.
VECTOR METHOD BASED ON MASS MOMENT VECTORS AND VECTOR ROTATORS APPLIED TO RIGID-BODY MULTI-COUPLED ROTATIONS AROUND NONINTERSECTING AXES
Authors: STEVANOVIĆ HEDRIH KATICA R.
Published: May 2013

The first part of the paper contains a short review of a series of published papers in the area of system dynamics with coupled rotations as well as of a series of author's various published research results in the area of vector method based on the mass inertia moment vectors and corresponding deviational vector components and vector rotators for the pole and oriented axis, introduced and defined by K. Hedrih in 1991. The vector with principal importance is vector of the rigid body mass inertia moment at the point and for the axis oriented by the unit vector, and with a corresponding component vector of the rigid body mass deviational moment for the rotation axis through the same pole. Second part presents the vector method based on mass moment vectors and vector rotators coupled for pole and oriented nonintersecting axes in application for obtaining vector expressions for kinetic parameters of a rigid body dynamics with multi-coupled rotations around nonintersecting axes. A complete analysis of obtained vector expressions for linear momentum and angular momentum and their corresponding derivatives gives us a series of the kinematical vector rotators around the corresponding directions determined by axes of the rigid body coupled multi-rotations around nonintersecting axes. Series of the theorems are defined.
ON FAMILIES IN DIFFERENTIAL GEOMETRY
Authors: MORENO GIOVANNI
Published: May 2013

Families of objects appear in several contexts, like algebraic topology, theory of deformations, theoretical physics, etc. An unified coordinate-free algebraic framework for families of geometrical quantities is presented here, which allows one to work without introducing ad hoc spaces, by using the language of differential calculus over commutative algebras. An advantage of such an approach, based on the notion of sliceable structures on cylinders, is that the fundamental theorems of standard calculus are straightforwardly generalized to the context of families. As an example of that, we prove the universal homotopy formula.
FROM HYPERSYMPLECTIC STRUCTURES TO COMPATIBLE PAIRS OF TENSORS ON A LIE ALGEBROID
Authors: ANTUNES P. , NUNES DA COSTA J. M.
Published: May 2013

A hypersymplectic structure on a Lie algebroid determines several Poisson–Nijenhuis, ΩN and PΩ structures on that Lie algebroid. We show that these Poisson–Nijenhuis (respectively, ΩN, PΩ) structures on the Lie algebroid, are pairwise compatible.
T-DUALITY INVARIANCE OF THE SUPERMEMBRANE
Authors: GARCÍA DEL MORAL MARÍA PILAR , PEÑA JOSELEN , RESTUCCIA ALVARO
Published: May 2013

We show that the supermembrane theory compactified on a torus is invariant under T-duality. There are two different topological sectors of the compactified supermembrane (M2) classified according to a vanishing or nonvanishing second cohomology class. We find the explicit T-duality transformation that acts locally on the supermembrane theory and we show that it is an exact symmetry of the theory. We give a global interpretation of the T-duality in terms of bundles. It has a natural description in terms of the cohomology of the base manifold and the homology of the target torus. We show that in the limit when the torus degenerate into a circle and the M2 mass operator restricts to the string-like configurations, the usual closed string T-duality transformation between the type IIA and type IIB mass operators is recovered. Moreover, if we just restrict M2 mass operator to string-like configurations but we perform a generalized T-duality we find the SL(2,Z) nonperturbative multiplet of IIA.
HIGHER-ORDER NOETHER SYMMETRIES IN k-SYMPLECTIC HAMILTONIAN FIELD THEORY
Authors: ROMÁN-ROY NARCISO , SALGADO MODESTO , VILARIÑO SILVIA
Published: May 2013

For k-symplectic Hamiltonian field theories, we study infinitesimal transformations generated by some kinds of vector fields which are not Noether symmetries, but which allow us to obtain conservation laws by means of suitable generalizations of Noether's theorem.
BIFURCATION CONTROL OF A PREDATOR–PREY MODEL BASED ON NUTRITION KINETICS
Authors: ZHAO LICHUN , LIU JINGNA , GAO WEI
Published: May 2013

The existence conditions of Hopf bifurcation for a predator–prey model based on nutrition kinetics are given. The two results may appear as follows: one is that the model has a stable periodic trajectory from Hopf bifurcation, which shows the system is in an ecological balance; the other is that periodic trajectory from Hopf bifurcation is unstable, which indicates the system is in a sharp or catastrophic loss of stability. For the latter, a bifurcation controller is designed to make the periodic trajectory stable. Finally, some simulations are carried out to prove the results.
THERMOELECTRIC PROPERTIES OF MANGANESE-DOPED p-TYPE SKUTTERUDITES CeyFe4-xMnxSb12
Authors: QIU PENGFEI , SHI XUN , LIU RUIHENG , QIU YUTING , WAN SHUN , CHEN LIDONG
Published: May 2013

R y Fe 4 Sb 12-based filled skutterudites have been studied extensively as p-type legs used in high-temperature thermoelectric generator. One approach to further improve their thermoelectric performance is to optimize the overhigh hole concentration in R y Fe 4 Sb 12 skutterudite. In this study, we used element Mn doped on the skutterudite framework and systemically investigated the effects of Mn on the filler filling fractions, crystal structures, and high-temperature thermoelectric properties in Ce y Fe 4-x Mn x Sb 12. It is found that the Mn doping limit at Fe sites is around 0.15. Mn doping slightly enhances Ce filling fractions because Mn acts as an electron acceptor and its doping could push more electron donator Ce into the voids of skutterudites. Although Mn has one valence electron less than Fe , the excessive electrons donated by Ce fillers can completely compensate the holes generated by Mn and reduce the material's hole concentration, leading to a much reduced electrical conductivity and electrical thermal conductivity. Since the lattice thermal conductivities of Mn -doped samples are almost unchanged as compared with that of the matrix, the total thermal conductivities are obviously decreased. Meanwhile, high power factors are maintained in Mn -doped samples because of the enhanced Seebeck coefficient as well as the undegraded carrier mobility. As a combined effect, the figure of merit in Mn -doped samples is much improved in the whole temperature range. Sample CeFe 3.85 Mn 0.15 Sb 12 exhibits a maximum value of 0.98 at 800 K among all the samples investigated in this work.
ELECTRONIC STRUCTURE AND LINEAR OPTICAL PROPERTIES OF MIXED ALKALI-METAL BOROPHOSPHATES (LiK2BP2O8, Li3K2BP4O14): A FIRST-PRINCIPLES STUDY
Authors: ZHANG BEI , JING QUN , YANG ZHIHUA , WANG YING , SU XIN , PAN SHILIE , ZHANG JUN
Published: May 2013

LiK 2 BP 2 O 8 and Li 3 K 2 BP 4 O 14 are synthesized by high-temperature solution method with the same elements, while contain different fundamental building units. Li 3 K 2 BP 4 O 14 is a novel P – O – P linking structure which gives a rare example of violation of Pauling's fourth rule. The electronic structures of LiK 2 BP 2 O 8 and Li 3 K 2 BP 4 O 14 are investigated by density functional calculations. Direct gaps of 5.038 eV ( LiK 2 BP 2 O 8) and 5.487 eV ( Li 3 K 2 BP 4 O 14) are obtained. By analyzing the density of states (DOS) of LiK 2 BP 2 O 8 and Li 3 K 2 BP 4 O 14, the P – O – P linking in fundamental building units of Li 3 K 2 BP 4 O 14 crystal is proved theoretically. Based on the electronic properties, the linear optical information is captured.
Sequential rationality in cryptographic protocols
Authors: Gradwohl Ronen , Livne Noam , Rosen Alon
Published: May 2013

Much of the literature on rational cryptography focuses on analyzing the strategic properties of cryptographic protocols. However, due to the presence of computationally-bounded players and the asymptotic nature of cryptographic security, a definition of sequential rationality for this setting has thus far eluded researchers.

We propose a new framework for overcoming these obstacles, and provide the first definitions of computational solution concepts that guarantee sequential rationality. We argue that natural computational variants of subgame perfection are too strong for cryptographic protocols. As an alternative, we introduce a weakening called threat-free Nash equilibrium that is more permissive but still eliminates the undesirable “empty threats” of nonsequential solution concepts.

To demonstrate the applicability of our framework, we revisit the problem of implementing a mediator for correlated equilibria [Dodis et al 2000], and propose a variant of their protocol that is sequentially rational for a nontrivial class of correlated equilibria. Our treatment provides a better understanding of the conditions under which mediators in a correlated equilibrium can be replaced by a stable protocol.
A game-theoretic analysis of the ESP game
Authors: Jain Shaili , Parkes David C.
Published: May 2013

“Games with a Purpose” are interactive games that users play because they are fun, with the added benefit that the outcome of play is useful work. The ESP game, developed byy von Ahn and Dabbish [2004], is an example of such a game devised to label images on the web. Since labeling images is a hard problem for computer vision algorithms and can be tedious and time-consuming for humans, the ESP game provides humans with incentive to do useful work by being enjoyable to play. We present a simple game-theoretic model of the ESP game and characterize the equilibrium behavior in our model. Our equilibrium analysis supports the fact that users appear to coordinate on low effort words. We provide an alternate model of user preferences, modeling a change that could be induced through a different scoring method, and show that equilibrium behavior in this model coordinates on high-effort words. We also give sufficient conditions for coordinating on high-effort words to be a Bayesian-Nash equilibrium. Our results suggest the possibility of formal incentive design in achieving desirable system-wide outcomes for the purpose of human computation, complementing existing considerations of robustness against cheating and human factors.
Optimal payments in dominant-strategy mechanisms for single-parameter domains
Authors: Naroditskiy Victor , Polukarov Maria , Jennings Nicholas R.
Published: May 2013

We study dominant-strategy mechanisms in allocation domains where agents have one-dimensional types and quasilinear utilities. Taking an allocation function as an input, we present an algorithmic technique for finding optimal payments in a class of mechanism design problems, including utilitarian and egalitarian allocation of homogeneous items with nondecreasing marginal costs. Our results link optimality of payment functions to a geometric condition involving triangulations of polytopes. When this condition is satisfied, we constructively show the existence of an optimal payment function that is piecewise linear in agent types.
Functioning of an arteriovenous fistula requires heme oxygenase-2
Authors: Kang Lu , Grande Joseph P. , Farrugia Gianrico , Croatt Anthony J. , Katusic Zvonimir S. , Nath Karl A.
Published: May 2013

Heme oxygenase-2 (HO-2), the constitutive isoform of the heme-degrading enzyme heme oxygenase, may serve as an anti-inflammatory vasorelaxant, in part, by generating carbon monoxide. Arteriovenous fistulas (AVFs) are employed as hemodialysis vascular accesses because they provide an accessible, high-blood-flow vascular segment. We examined the role of vascular expression of HO-2 in AVF function. An AVF was created in mice by anastomosing the carotid artery to the jugular vein. HO-2 expression was detected by immunohistochemistry in the intact carotid artery, mainly in endothelial cells and smooth muscle cells; expression of HO-2 protein and mRNA was modestly increased in the artery of the AVF. Creating an AVF in HO-2−/−mice compared with an AVF in HO-2+/+mice led to markedly reduced AVF blood flow and increased numbers of nonfunctioning AVFs. The impairment of AVF function in the setting of HO-2 deficiency could not be ascribed to either preexisting intrinsic abnormalities in endothelium-dependent and endothelium-independent relaxation of the carotid artery in HO-2-deficient mice or to impaired vasorelaxant responses in the intact carotid artery in vivo. HO-1 mRNA was comparably induced in the AVF in HO-2+/+and HO-2−/−mice, whereas the AVF in HO-2−/−mice compared with that in HO-2+/+mice exhibited exaggerated induction of matrix metalloproteinase (MMP)-9 but similar induction of MMP-2. HO-2 deficiency also led to lower AVF blood flow when AVFs were created in uremia, the latter induced by subtotal nephrectomy. We conclude that HO-2 critically contributes to the adequacy of AVF blood flow and function.
Global attractor alphabet of neural firing modes
Authors: Baram Yoram
Published: May 2013

The elementary set, or alphabet, of neural firing modes is derived from the widely accepted conductance-based rectified firing-rate model. The firing dynamics of interacting neurons are shown to be governed by a multidimensional bilinear threshold discrete iteration map. The parameter-dependent global attractors of the map morph into 12 attractor types. Consistent with the dynamic modes observed in biological neuronal firing, the global attractor alphabet is highly visual and intuitive in the scalar, single-neuron case. As synapse permeability varies from high depression to high potentiation, the global attractor type varies from chaotic to multiplexed, oscillatory, fixed, and saturated. As membrane permeability decreases, the global attractor transforms from active to passive state. Under the same activation, learning and retrieval end at the same global attractor. The bilinear threshold structure of the multidimensional map associated with interacting neurons generalizes the global attractor alphabet of neuronal firing modes to multineuron systems. Selective positive or negative activation and neural interaction yield combinatorial revelation and concealment of stored neuronal global attractors.