bluuebunny/crossref_metadata_2025_split huggingface dataset:
Minimal models for -coverings of elliptic curves
Authors: Fisher Tom 
Published: August 2014

AbstractIn this paper we give a new formula for adding$2$-coverings and$3$-coverings of elliptic curves that avoids the need for any field extensions. We show that the$6$-coverings obtained can be represented by pairs of cubic forms. We then prove a theorem on the existence of such models with integer coefficients and the same discriminant as a minimal model for the Jacobian elliptic curve. This work has applications to finding rational points of large height on elliptic curves.
On the computation of the determinant of vector-valued Siegel modular forms
Authors: Takemori Sho 
Published: August 2014

AbstractLet $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}A^{0}(\Gamma _{2})$ denote the ring of scalar-valued Siegel modular forms of degree two, level $1$ and even weights. In this paper, we prove the determinant of a basis of the module of vector-valued Siegel modular forms $\bigoplus _{k \equiv \epsilon \ {\rm mod}\ {2}}A_{\det ^{k}\otimes \mathrm{Sym}(j)}(\Gamma _{2})$ over $A^{0}(\Gamma _{2})$ is equal to a power of the cusp form of degree two and weight $35$ up to a constant. Here $j = 4, 6$ and $\epsilon = 0, 1$. The main result in this paper was conjectured by Ibukiyama (Comment. Math. Univ. St. Pauli 61 (2012) 51–75).
Computing in quotients of rings of integers
Authors: Fieker Claus , Hofmann Tommy 
Published: August 2014

AbstractWe develop algorithms to turn quotients of rings of integers into effective Euclidean rings by giving polynomial algorithms for all fundamental ring operations. In addition, we study normal forms for modules over such rings and their behavior under certain quotients. We illustrate the power of our ideas in a new modular normal form algorithm for modules over rings of integers, vastly outperforming classical algorithms.
Parametrizing the moduli space of curves and applications to smooth plane quartics over finite fields
Authors: Lercier Reynald , Ritzenthaler Christophe , Rovetta Florent , Sijsling Jeroen 
Published: August 2014

AbstractWe study new families of curves that are suitable for efficiently parametrizing their moduli spaces. We explicitly construct such families for smooth plane quartics in order to determine unique representatives for the isomorphism classes of smooth plane quartics over finite fields. In this way, we can visualize the distributions of their traces of Frobenius. This leads to new observations on fluctuations with respect to the limiting symmetry imposed by the theory of Katz and Sarnak.
Class numbers of real cyclotomic fields of composite conductor
Authors: Miller John C. 
Published: August 2014

AbstractUntil recently, the ‘plus part’ of the class numbers of cyclotomic fields had only been determined for fields of root discriminant small enough to be treated by Odlyzko’s discriminant bounds.However, by finding lower bounds for sums over prime ideals of the Hilbert class field, we can now establish upper bounds for class numbers of fields of larger discriminant. This new analytic upper bound, together with algebraic arguments concerning the divisibility properties of class numbers, allows us to unconditionally determine the class numbers of many cyclotomic fields that had previously been untreatable by any known method.In this paper, we study in particular the cyclotomic fields of composite conductor.
The Activity of Glycopeptide Antibiotics against Resistant Bacteria Correlates with Their Ability To Induce the Resistance System
Authors: Kwun Min Jung , Hong Hee-Jeon 
Published: August 2014

ABSTRACT

Glycopeptide antibiotics containing a hydrophobic substituent display the best activity against vancomycin-resistant enterococci, and they have been assumed to be poor inducers of the resistance system. Using a panel of 26 glycopeptide derivatives and the model resistance system in
Streptomyces coelicolor
, we confirmed this hypothesis at the level of transcription. Identification of the structural glycopeptide features associated with inducing the expression of resistance genes has important implications in the search for more effective antibiotic structures.
Thorax Injury Lowers Resistance to Infection in Drosophila melanogaster
Authors: Chambers Moria C. , Jacobson Eliana , Khalil Sarah , Lazzaro Brian P. 
Published: August 2014

ABSTRACT

The route of infection can profoundly affect both the progression and outcome of disease. We investigated differences in
Drosophila melanogaster
defense against infection after bacterial inoculation into two sites—the abdomen and the thorax. Thorax inoculation results in increased bacterial proliferation and causes high mortality within the first few days of infection. In contrast, abdomen inoculation results in minimal mortality and lower bacterial loads than thorax inoculation. Inoculation into either site causes systemic infection. Differences in mortality and bacterial load are due to injury of the thorax and can be recapitulated by abdominal inoculation coupled with aseptic wounding of the thorax. This altered resistance appears to be independent of classical immune pathways and opens new avenues of research on the role of injury during defense against infection.
Probing the Structure of the S105 Hole
Authors: To Kam H. , Young Ry 
Published: August 2014

ABSTRACT

For most phages, holins control the timing of host lysis. During the morphogenesis period of the infection cycle, canonical holins accumulate harmlessly in the cytoplasmic membrane until they suddenly trigger to form lethal lesions called holes. The holes can be visualized by cryo-electron microscopy and tomography as micrometer-scale interruptions in the membrane. To explore the fine structure of the holes formed by the lambda holin, S105, a cysteine-scanning accessibility study was performed. A collection of
S105
alleles encoding holins with a single Cys residue in different positions was developed and characterized for lytic function. Based on the ability of 4-acetamido-4′-((iodoacetyl) amino) stilbene-2,2′-disulfonic acid, disodium salt (IASD), to modify these Cys residues, one face of transmembrane domain 1 (TMD1) and TMD3 was judged to face the lumen of the S105 hole. In both cases, the lumen-accessible face was found to correspond to the more hydrophilic face of the two TMDs. Judging by the efficiency of IASD modification, it was concluded that the bulk of the S105 protein molecules were involved in facing the lumen. These results are consistent with a model in which the perimeters of the S105 holes are lined by the holin molecules present at the time of lysis. Moreover, the findings that TMD1 and TMD3 face the lumen, coupled with previous results showing TMD2-TMD2 contacts in the S105 dimer, support a model in which membrane depolarization drives the transition of S105 from homotypic to heterotypic oligomeric interactions.
Maturation of the Human Papillomavirus 16 Capsid
Authors: Cardone Giovanni , Moyer Adam L. , Cheng Naiqian , Thompson Cynthia D. , Dvoretzky Israel , Lowy Douglas R. , Schiller John T. , Steven Alasdair C. , Buck Christopher B. , Trus Benes L. 
Published: August 2014

ABSTRACT

Papillomaviruses are a family of nonenveloped DNA viruses that infect the skin or mucosa of their vertebrate hosts. The viral life cycle is closely tied to the differentiation of infected keratinocytes. Papillomavirus virions are released into the environment through a process known as desquamation, in which keratinocytes lose structural integrity prior to being shed from the surface of the skin. During this process, virions are exposed to an increasingly oxidative environment, leading to their stabilization through the formation of disulfide cross-links between neighboring molecules of the major capsid protein, L1. We used time-lapse cryo-electron microscopy and image analysis to study the maturation of HPV16 capsids assembled in mammalian cells and exposed to an oxidizing environment after cell lysis. Initially, the virion is a loosely connected procapsid that, under
in vitro
conditions, condenses over several hours into the more familiar 60-nm-diameter papillomavirus capsid. In this process, the procapsid shrinks by ~5% in diameter, its pentameric capsomers change in structure (most markedly in the axial region), and the interaction surfaces between adjacent capsomers are consolidated. A C175S mutant that cannot achieve normal inter-L1 disulfide cross-links shows maturation-related shrinkage but does not achieve the fully condensed 60-nm form. Pseudoatomic modeling based on a 9-Å resolution reconstruction of fully mature capsids revealed C-terminal disulfide-stabilized “suspended bridges” that form intercapsomeric cross-links. The data suggest a model in which procapsids exist in a range of dynamic intermediates that can be locked into increasingly mature configurations by disulfide cross-linking, possibly through a Brownian ratchet mechanism.

IMPORTANCE
Human papillomaviruses (HPVs) cause nearly all cases of cervical cancer, a major fraction of cancers of the penis, vagina/vulva, anus, and tonsils, and genital and nongenital warts. HPV types associated with a high risk of cancer, such as HPV16, are generally transmitted via sexual contact. The nonenveloped virion of HPVs shows a high degree of stability, allowing the virus to persist in an infectious form in environmental fomites. In this study, we used cryo-electron microscopy to elucidate the structure of the HPV16 capsid at different stages of maturation. The fully mature capsid adopts a rigid, highly regular structure stabilized by intermolecular disulfide bonds. The availability of a pseudoatomic model of the fully mature HPV16 virion should help guide understanding of antibody responses elicited by HPV capsid-based vaccines.
Prognostic Implications of Left Ventricular Dyssynchrony for Major Adverse Cardiovascular Events in Asymptomatic Women and Men: The Multi‐Ethnic Study of Atherosclerosis
Authors: Sharma Ravi K. , Volpe Gustavo , Rosen Boaz D. , Ambale‐Venkatesh Bharat , Donekal Sirisha , Fernandes Veronica , Wu Colin O. , Carr Jeffrey , Bluemke David A. , Lima João A. C. 
Published: August 2014

Background

Left ventricular (
LV
) dyssynchrony is related to adverse outcomes in systolic heart failure, but its prognostic importance in asymptomatic population is not known. Our objective was to assess the prognostic implications of
LV
mechanical dyssynchrony in a large multiethnic population before the occurrence of global
LV
dysfunction.

Methods and Results

A total of 1392 participants in the Multi‐Ethnic Study of Atherosclerosis (
MESA
; mean age: 64.7 years; 46% were women) with cardiac magnetic resonance imaging at baseline were followed for a median duration of 8.3 years.
Harmonic phase imaging
analysis was used to derive systolic circumferential strain. Greater standard deviation of time to peak systolic strain (
SD
‐
TPS
) indicates greater dyssynchrony. With
SD
‐
TPS
as a continuous variable, Cox proportional hazards analysis was used to assess hazards ratio after adjusting for demographics, cardiovascular risk factors,
LV
mass‐to‐volume ratio, and ejection fraction. Using the 75th percentile of
SD
‐
TPS
as a cutoff, Kaplan–Meier analysis was performed between 2 categorical groups for each gender. Higher values of dyssynchrony in women predicted major adverse cardiovascular events, defined as myocardial infarction, heart failure, stroke, and death (hazard ratio
:
1.01 per 1‐ms increment in
SD
‐
TPS
,
P
=0.015), hard coronary events (
hazard ratio:
1.05 per 1‐ms increment in
SD
‐
TPS
,
P
=0.026), and cerebrovascular events (
hazard ratio:
1.03 per 1‐ms increment in
SD
‐
TPS
,
P
=0.013). In contrast, dyssynchrony in men was not predictive of events. Kaplan–Meier analyses in women revealed increased event occurrence in the higher dyssynchrony group, but this was not the case in men.

Conclusions

In an asymptomatic cohort, greater
LV
dyssynchrony determined by
cardiac magnetic resonance imaging
predicts adverse cardiovascular outcome in women but not in men.

Clinical Trial Registration

URL:
http://clinicaltrials.gov
. Unique identifier: NCT00005487.
Ototoxic Effect of Ultrastop Antifog Solution Applied to the Guinea Pig Middle Ear
Authors: Nomura Kazuhiro , Oshima Hidetoshi , Yamauchi Daisuke , Hidaka Hiroshi , Kawase Tetsuaki , Katori Yukio 
Published: August 2014

ObjectivesRecent advances in endoscopic technology have allowed its application to middle ear surgery. An antifog agent is necessary for endoscopy because moisture and blood may obscure visibility. Ultrastop is one of the most commonly used antifog agents. The current study examined the ototoxic effect of topical application of Ultrastop in the guinea pig ear.Study DesignA preliminary experimental animal study.SettingUniversity hospital.Subjects and MethodsEighteen male Hartley guinea pigs (weight, 480‐620 g) were divided into 3 groups to be treated with Ultrastop, gentamicin (50 mg/mL, positive control), or saline solution (negative control). After auditory brainstem responses were measured, topical solutions of 0.2 mL were applied through a small hole made at the tympanic bulla. Posttreatment auditory brainstem responses were obtained 14 days after the treatment. The extent of middle ear damage was investigated and scored.ResultsThe saline‐treated group showed no deterioration in auditory brainstem response threshold. The Ultrastop‐treated and gentamicin‐treated groups showed severe deterioration in auditory brainstem response threshold. Middle ear examination revealed extensive changes in the Ultrastop‐treated group and medium changes in the gentamicin‐treated group.ConclusionUltrastop applied topically to the guinea pig middle ear caused significant middle ear inflammation and hearing impairment.
Silencing airway epithelial cell-derived hepcidin exacerbates sepsis-induced acute lung injury
Authors: Chen Qi Xing , Song Sheng Wen , Chen Qing Hua , Zeng Cong Li , Zheng Xia , Wang Jun Lu , Fang Xiang Ming 
Published: August 2014

Abstract
Introduction
The production of antimicrobial peptides by airway epithelial cells is an important component of the innate immune response to pulmonary infection and inflammation. Hepcidin is a β-defensin-like antimicrobial peptide and acts as a principal iron regulatory hormone. Hepcidin is mostly produced by hepatocytes, but is also expressed by other cells, such as airway epithelial cells. However, nothing is known about its function in lung infections and inflammatory diseases. We therefore sought to investigate the role of airway epithelial cell-derived hepcidin in sepsis-induced acute lung injury.

Methods
Acute lung injury was induced by polymicrobial sepsis via cecal ligation and puncture (CLP) surgery. Adenovirus-mediated short hairpin RNA specific for the mouse hepcidin gene hepc1 and control adenovirus were intratracheally injected into mice. The adenovirus-mediated knockdown of hepcidin in airway epithelial cells was evaluated in vivo. Lung injury and the seven-day survival rate were assessed. The levels of hepcidin-related iron export protein ferroportin were measured, and the iron content and function of alveolar macrophages were evaluated.

Results
The hepcidin level in airway epithelial cells was upregulated during polymicrobial sepsis. The knockdown of airway epithelial cell-derived hepcidin aggravated the polymicrobial sepsis-induced lung injury and pulmonary bacterial infection and increased mortality (53.33% in Ad-shHepc1-treated mice versus 12.5% in Ad-shNeg-treated mice, P <0.05). The knockdown of hepcidin in airway epithelial cells also led to reduced ferroportin degradation and a low intracellular iron content in alveolar macrophages. Moreover, alveolar macrophages form the airway epithelial cell-derived hepcidin knockdown mice showed impaired phagocytic ability than those from the control mice.

Conclusions
Airway epithelial cell-derived hepcidin plays an important role in CLP-induced acute lung injury. The severe lung injury in the airway epithelial cell-derived hepcidin knockdown mice is at least partially related to the altered intracellular iron level and function of alveolar macrophages.
Somatic Mutations Predict Poor Outcome in Patients With Myelodysplastic Syndrome After Hematopoietic Stem-Cell Transplantation
Authors: Bejar Rafael , Stevenson Kristen E. , Caughey Bennett , Lindsley R. Coleman , Mar Brenton G. , Stojanov Petar , Getz Gad , Steensma David P. , Ritz Jerome , Soiffer Robert , Antin Joseph H. , Alyea Edwin , Armand Philippe , Ho Vincent , Koreth John , Neuberg Donna , Cutler Corey S. , Ebert Benjamin L. 
Published: August 2014

Purpose Recurrently mutated genes in myelodysplastic syndrome (MDS) are pathogenic drivers and powerfully associated with clinical phenotype and prognosis. Whether these types of mutations predict outcome after allogeneic hematopoietic stem-cell transplantation (HSCT) in patients with MDS is not known. Patients and Methods We used massively parallel sequencing to examine tumor samples collected from 87 patients with MDS before HSCT for coding mutations in 40 recurrently mutated MDS genes. Results Mutations were identified in 92% of patients, most frequently in the ASXL1 (29%), TP53 (21%), DNMT3A (18%), and RUNX1 (16%) genes. In univariable analyses, only TP53 mutations were associated with shorter overall (OS; hazard ratio [HR], 3.74; P < .001) and progression-free survival (HR, 3.97; P < .001). After adjustment for clinical variables associated with these end points, mutations in TP53 (HR, 2.30; P = .027), TET2 (HR, 2.40; P = .033), and DNMT3A (HR, 2.08; P = .049) were associated with decreased OS. In multivariable analysis including clinical variables, complex karyotype status, and candidate genes, mutations in TP53 (HR, 4.22; P ≤ .001) and TET2 (HR, 1.68; P = .037) were each independently associated with shorter OS. Nearly one half of patients (46%) carried a mutation in TP53, DNMT3A, or TET2 and accounted for 64% of deaths. Three-year OS in patients without these mutations was 59% (95% CI, 43% to 72%), versus 19% (95% CI, 9% to 33%) in patients with these mutations. Conclusion Mutations in TP53, TET2, or DNMT3A identify patients with MDS with shorter OS after HSCT.
Uncarboxylated Osteocalcin Stimulates 25-Hydroxy Vitamin D Production in Leydig Cell Line Through a GPRC6a-Dependent Pathway
Authors: De Toni Luca , De Filippis Vincenzo , Tescari Simone , Ferigo Marco , Ferlin Alberto , Scattolini Valentina , Avogaro Angelo , Vettor Roberto , Foresta Carlo 
Published: August 2014

AbstractRecent studies disclosed a cross talk between testis and bone. By the action of LH, Leydig cells are able to modulate bone metabolism through testosterone and insulin-like factor 3. Moreover, LH modulates the Leydig expression of CYP2R1, the key enzyme involved in vitamin D (Vit D) 25-hydroxylation. However, pathways regulating CYP2R1 expression have been poorly investigated. The cross talk from the bone to the testis of the vitamin D 25-hydroxylase CYP2R1 involves osteocalcin (OC), which is produced by the osteoblasts and stimulates the production of testosterone by the Leydig cells through its putative receptor GPRC6A, a cation-sensing G-protein-coupled receptor. The aim of this study was to investigate the possible action of OC on CYP2R1 expression and 25-hydroxy Vit D (25-OH Vit D) production in a mouse Leydig cell line (MA-10). After confirmation of the expression of GPRC6A by MA-10, we found that stimulation with either human chorionic gonadotropin or uncarboxylated-OC (ucOC) increases CYP2R1 protein expression in a dose-dependent manner and, in turn, increases the release of 25-OH Vit D in culture medium. This effect was abolished by receptor blockade with, respectively, anti-LH receptor and anti-GPRC6A antibodies. Moreover, both agonists converged to phosphorylation of Erk1/2 by a likely differential action on second messengers. Human chorionic gonadotropin induced slow “tonic” increase of intercellular calcium and accumulation of cAMP, whereas ucOC mainly induced phasic increase of cell calcium. Supporting these findings, we found that serum ucOC positively correlated with 25-OH Vit D levels in 40 overweight male patients and 21 controls. Altogether, our results suggest that OC contributes with LH to 25-OH Vit D production by Leydig cells.
Time-Delay Interferometry
Authors: Tinto Massimo , Dhurandhar Sanjeev V. 
Published: August 2014

AbstractEqual-arm detectors of gravitational radiation allow phase measurements many orders of magnitude below the intrinsic phase stability of the laser injecting light into their arms. This is because the noise in the laser light is common to both arms, experiencing exactly the same delay, and thus cancels when it is differenced at the photo detector. In this situation, much lower level secondary noises then set the overall performance. If, however, the two arms have different lengths (as will necessarily be the case with space-borne interferometers), the laser noise experiences different delays in the two arms and will hence not directly cancel at the detector. In order to solve this problem, a technique involving heterodyne interferometry with unequal arm lengths and independent phase-difference readouts has been proposed. It relies on properly time-shifting and linearly combining independent Doppler measurements, and for this reason it has been called time-delay interferometry (TDI).This article provides an overview of the theory, mathematical foundations, and experimental aspects associated with the implementation of TDI. Although emphasis on the application of TDI to the Laser Interferometer Space Antenna (LISA) mission appears throughout this article, TDI can be incorporated into the design of any future space-based mission aiming to search for gravitational waves via interferometric measurements. We have purposely left out all theoretical aspects that data analysts will need to account for when analyzing the TDI data combinations.