bluuebunny/crossref_metadata_2025_split huggingface dataset:
RESPONSES OF TWO LETTUCE CULTIVARS TO IRON DEFICIENCY
Authors: MSILINI NAJOUA , ATTIA HOUNEIDA , RABHI MOKDED , KARRAY NAJOUA , LACHAÂL MOKHTAR , OUERGHI ZEINEB 
Published: July 2012

SUMMARYA comparative study of two lettuce varieties (Lactuca sativa: ‘Romaine’ and ‘Vista’) was conducted to understand the effect of iron deficiency on growth, biomass allocation, chlorophyll fluorescence and root and leaf enzymatic activity. After 15 days of growth in hydroponic solution under Fe-deficient and Fe-sufficient conditions, leaf chlorophyll concentration, activities of ribulose 1.5-bisphosphate carboxylase/oxygenase (Rubisco) in leaves extract, ferric chelate reductase (FCR) and phosphoenolpyruvate carboxylase (PEPC) in root extracts were measured. We found that there were significant differences in fresh matter accumulation and pigment concentration between the varieties. Fresh weight and total leaf area and leaf number were significantly reduced under iron deficiency. There was also a significant decrease in photosynthetic pigment concentration in both varieties. In response to Fe deficiency, ‘Vista’ variety showed higher FCR and PEPC activities compared to ‘Romaine’ variety. Moreover, this increase was accompanied by an enhanced accumulation of phenolic compound in roots of ‘Vista’ variety. These findings show that ‘Romaine’ was more affected by iron deficiency than ‘Vista’.
First record of Mesozoic terrestrial vertebrates from Lithuania: phytosaurs (Diapsida: Archosauriformes) of probable Late Triassic age, with a review of phytosaur biogeography
Authors: BRUSATTE STEPHEN L. , BUTLER RICHARD J. , NIEDŹWIEDZKI GRZEGORZ , SULEJ TOMASZ , BRONOWICZ ROBERT , SATKŪNAS JONAS 
Published: July 2012

AbstractFossils of Mesozoic terrestrial vertebrates from Lithuania and the wider East Baltic region of Europe have previously been unknown. We here report the first Mesozoic terrestrial vertebrate fossils from Lithuania: two premaxillary specimens and three teeth that belong to Phytosauria, a common clade of semiaquatic Triassic archosauriforms. These specimens represent an uncrested phytosaur, similar to several species within the generaPaleorhinus,Parasuchus,RutiodonandNicrosaurus. Because phytosaurs are currently only known from the Upper Triassic, their discovery in northwestern Lithuania (the Šaltiškiai clay-pit) suggests that at least part of the Triassic succession in this region is Late Triassic in age, and is not solely Early Triassic as has been previously considered. The new specimens are among the most northerly occurrences of phytosaurs in the Late Triassic, as Lithuania was approximately 7–10° further north than classic phytosaur-bearing localities in nearby Germany and Poland, and as much as 40° further north than the best-sampled phytosaur localities in North America. The far northerly occurrence of the Lithuanian fossils prompts a review of phytosaur biogeography and distribution, which suggests that these predators were widely distributed in the Triassic monsoonal belt but rarer in more arid regions.
Temporomandibular joint fistula into the external ear canal
Authors: Ajduk J , Ries M , Vagic D , Batos-Tripalo A 
Published: July 2012

AbstractBackground:Temporomandibular joint fistula into the external auditory canal is a very rare condition. We report a case of spontaneous fistula which presented with repeated episodes of clear fluid otorrhoea and ear infection.Case report:A 53-year-old woman complained of occasional episodes of clear fluid otorrhoea from the right ear followed by infection. Otoscopic examination showed a normal tympanic membrane and normal skin in the external auditory meatus. Otomicroscopy showed a small punctum on the anteroinferior part of the meatus. Computed tomography identified a foramen of Huschke. Surgery revealed a fistula between the meatus and the temporomandibular joint, which was successfully resolved.Conclusion:This report presents a rare case of a fistula between the temporomandibular joint and the external auditory meatus, associated with Huschke's foramen. Such a defect can be quite difficult to detect. It should be suspected in cases of chronic otorrhoea when neither middle nor external ear disease is apparent. Surgery is usually successful, and is advised in cases with repeated complications.
Cannabis or alcohol first? Differences by ethnicity and in risk for rapid progression to cannabis-related problems in women
Authors: Sartor C. E. , Agrawal A. , Lynskey M. T. , Duncan A. E. , Grant J. D. , Nelson E. C. , Madden P. A. F. , Heath A. C. , Bucholz K. K. 
Published: July 2012

BackgroundInitiation of cannabis use typically follows alcohol use, but the reverse order does occur and is more common for African-Americans (AAs) than European-Americans (EAs). The aim of this study was to test for differences in the order of initiation of cannabis and alcohol use between AA and EA women and to determine whether order and ethnicity contribute independently to risk for rapid progression to cannabis-related problems.MethodData were drawn from structured psychiatric interviews of 4102 women (mean age = 21.6 years), 3787 from an all-female twin study and 315 from a high-risk family study; 18.1% self-identified as AA, 81.9% as EA. Ethnicity and order of initiation of cannabis and alcohol use were modeled as predictors of transition time from first use to onset of cannabis use disorder symptom(s) using Cox proportional hazards regression analyses.ResultsAA women were nearly three times as likely as EA women to initiate cannabis use before alcohol use. Using cannabis before alcohol [hazard ratio (HR) 1.44, 95% confidence interval (CI) 1.08–1.93] and AA ethnicity (HR 1.59, 95% CI 1.13–2.24) were both associated with rapid progression from first use to cannabis symptom onset even after accounting for age at initiation and psychiatric risk factors.ConclusionsThe findings indicate that AA women are at greater risk for rapid development of cannabis-related problems than EA women and that this risk is even higher when cannabis use is initiated before alcohol use. Prevention programs should be tailored to the various patterns of cannabis use and relative contributions of risk factors to the development of cannabis-related problems in different ethnic groups.
Spiders’ webs and locally connected Julia sets of transcendental entire functions
Authors: OSBORNE J. W. 
Published: July 2012

AbstractWe show that if the Julia set of a transcendental entire function is locally connected, then it takes the form of a spider’s web in the sense defined by Rippon and Stallard. In the opposite direction, we prove that a spider’s web Julia set is always locally connected at a dense subset of buried points. We also show that the set of buried points (the residual Julia set) can be a spider’s web.
Learning to swim: a dynamical systems approach to mimicking fish swimming with CPG
Authors: Wang Tianmiao , Hu Yonghui , Liang Jianhong 
Published: July 2012

SUMMARYCentral Pattern Generators (CPGs) can generate robust, smooth and coordinated oscillatory signals for locomotion control of robots with multiple degrees of freedom, but the tuning of CPG parameters for a desired locomotor pattern constitutes a tremendously difficult task. This paper addresses this problem for the generation of fish-like swimming gaits with an adaptive CPG network on a multi-joint robotic fish. Our approach converts the related CPG parameters into dynamical systems that evolve as part of the CPG network dynamics. To reproduce the bodily motion of swimming fish, we use the joint angles calculated with the trajectory approximation method as teaching signals for the CPG network, which are modeled as a chain of coupled Hopf oscillators. A novel coupling scheme is proposed to eliminate the influence of afferent signals on the amplitude of the oscillator. The learning rules of intrinsic frequency, coupling weight and amplitude are formulated with phase space representation of the oscillators. The frequency, amplitudes and phase relations of the teaching signals can be encoded by the CPG network with adaptation mechanisms. Since the Hopf oscillator exhibits limit cycle behavior, the learned locomotor pattern is stable against perturbations. Moreover, due to nonlinear characteristics of the CPG model, modification of the target travelling body wave can be carried out in a smooth way. Numerical experiments are conducted to validate the effectiveness of the proposed learning rules.
Seboxplays an important role during the early mouse oogenesisin vitro
Authors: Moreno Dafne Linda , Salazar Zayil , Betancourt Miguel , Casas Eduardo , Ducolomb Yvonne , González Cristina , Bonilla Edmundo 
Published: July 2012

SummaryOogenesis is a highly complex process that requires the exquisite temporal and spatial regulation of gene expression at multiple levels. Skin–embryo–brain–oocyte homeobox (Sebox) gene encodes a transcription factor that is highly expressed in germinal vesicle stage oocytes and that plays an essential role in early embryogenesis at the 2-cell stage in the mouse. AsSeboxis also expressed in mouse fetal ovaries, the aim of the present study was to study its role during the early oogenesisin vitro. Expression ofSeboxwas low in 15.5 to 17.5 days post coitum (dpc) ovaries, showed a peak at 18.5 dpc and then its expression decreased dramatically in newborn ovaries.Seboxexpression was efficiently knocked down (>80%) in fetal mouse ovary explants in culture using RNAi technology. When fetal ovary explants were transfected withSebox-specific RNAi, the number of oocytes at germinal vesicle stage and showing a diameter of 40–70 μm was decreased significantly to 75% after 7 days of culture relative to the negative control, and to 22.4% after 10 days of culture, thus indicating thatSeboxplays an important role in the early oogenesis in mice.
Large electronic bandwidth in solution-processable pyrene crystals: The role of close-packed crystal structure
Authors: Provencher Françoise , Bérubé Nicolas , Laprade Jean-Frédéric , Simard Gabrielle , Tant Julien , de Halleux Véronique , Geerts Yves , Silva Carlos , Côté Michel 
Published: July 2012

We examine the interdependence of structural and electronic properties of two substituted pyrene crystals by means of combined spectroscopic probes and density-functional theory calculations. Substituted pyrenes are useful model systems to unravel the interplay of crystal structure and electronic properties in organic semiconductors. To study the effect of steric encumbrance on the crystalline arrangement of two 1,3,6,8-tetraalkynylpyrene derivatives, one features linear n-hexyl side groups while the other contains branched trimethylsilyl groups. Both derivatives form triclinic crystal structures when grown from solution, but the electronic dispersion behavior is significantly different due to differences in π–π overlap along the π-stacking axis. Both systems display dispersion of around 0.45 eV in the valence band, suggesting a high intrinsic hole mobility. However, the direction of the dispersion is different: it is primarily along the π-stacking axis in the trimethylsilyl-substituted derivative, but less aligned with this crystal axis in the hexyl-substituted molecule. This is a direct consequence of the differences in co-facial π electron overlap revealed by the crystallographic studies. We find that photophysical defects, ascribed to excimer-like states, point to the importance of localized trap states.
A high-field adiabatic fast passage ultracold neutron spin flipper for the UCNA experiment
Authors: Holley A. T. , Broussard L. J. , Davis J. L. , Hickerson K. , Ito T. M. , Liu C.-Y. , Lyles J. T. M. , Makela M. , Mammei R. R. , Mendenhall M. P. , Morris C. L. , Mortensen R. , Pattie R. W. , Rios R. , Saunders A. , Young A. R. 
Published: July 2012

The UCNA collaboration is making a precision measurement of the β asymmetry (A) in free neutron decay using polarized ultracold neutrons (UCN). A critical component of this experiment is an adiabatic fast passage neutron spin flipper capable of efficient operation in ambient magnetic fields on the order of 1 T. The requirement that it operate in a high field necessitated the construction of a free neutron spin flipper based, for the first time, on a birdcage resonator. The design, construction, and initial testing of this spin flipper prior to its use in the first measurement of A with UCN during the 2007 run cycle of the Los Alamos Neutron Science Center's 800 MeV proton accelerator is detailed. These studies determined the flipping efficiency of the device, averaged over the UCN spectrum present at the location of the spin flipper, to be \documentclass[12pt]{minimal}\begin{document}$\overline{\epsilon }=0.9985(4)$\end{document}ε¯=0.9985(4).
Inkjet printed carbon nanotube networks: the influence of drop spacing and drying on electrical properties
Authors: Wang Tianming , Roberts Michael A , Kinloch Ian A. , Derby Brian 
Published: July 2012

Abstract
We have measured the electrical resistance of inkjet printed multiwall carbon nanotube networks and found that it depends strongly on the temperature of the substrate during the printing process, with both the resistance and its anisotropy decreasing as temperature increases. A parallel investigation of the surface morphology of the printed networks found long raised ridges running parallel to the printing direction, with the height of the ridges decreasing with increasing substrate temperature. Both these observations are shown to be associated with segregation of the nanotubes during drying (coffee staining) and that this segregation is suppressed at higher substrate temperatures, with the lowest resistance values and anisotropy found with a substrate temperature of 70 °C. Network conductance was found to increase with increasing layer thickness and similar results are obtained through a reduction in drop spacing or by printing multiple layers.
A model of carbon nanotube synthesis in arc discharge plasmas
Authors: Kundrapu M , Li J , Shashurin A , Keidar M 
Published: July 2012

Abstract
Nanoparticle growth in arc discharges is analysed numerically. An analysis is carried out for the root growth method of nanotubes in plasmas. The existing models for estimating the growth of nanoparticles in stationary plasmas are extended to plasmas with variable properties. The distributions of velocity, species density and temperature from numerical simulations are used as input to the growth models. The nickel particle diameter obtained from the numerical model is 9.2 nm and the frequency of finding this size in the experiment is 26 on the larger side. The length of the single-walled carbon nanotube obtained from the model is 2.1 µm, which falls in the upper 10% of the size distribution from experiment. Parametric studies are carried out varying the arc current, inter-electrode gap and background pressure. Results showed 40–95% increment in the nanotube length by increasing the background pressure and the inter-electrode gap. A hot-chamber arc discharge method is proposed to maximize the growth of nanoparticles subjected to the conditions identical to those existing in convectional arc discharges.
Spatial Structure and Lamarckian Adaptation Explain Extreme Genetic Diversity at CRISPR Locus
Authors: Haerter Jan O. , Sneppen Kim 
Published: July 2012

ABSTRACTEven within similar bacterial strains, it has been found that the clustered, regularly interspaced short palindromic repeat (CRISPR) shows a large variability of spacers. Modeling bacterial strains with different levels of immunity to infection by a single virulent phage, we find that coexistence in a well-mixed environment is possible only when these levels are distinctly different. When bacterial strains are similar, one subpopulation collapses. In the case of bacteria with various levels of CRISPR immunity to a range of phages, small differences in spacer composition will accordingly be suppressed under well-mixed conditions. Using a numerical model of populations spreading in space, we predict that it is the Lamarckian nature of CRISPR evolution that combines with spatial correlations to sustain the experimentally observed distribution of spacer diversity.
Expression of the PTTG1 Oncogene Is Associated with Aggressive Clear Cell Renal Cell Carcinoma
Authors: Wondergem Bill , Zhang Zhongfa , Huang Dachuan , Ong Choon Kiat , Koeman Julie , Hof David Van't , Petillo David , Ooi Aikseng , Anema John , Lane Brian , Kahnoski Richard J. , Furge Kyle A. , Teh Bin Tean 
Published: July 2012

Abstract
The pituitary tumor transforming gene (PTTG1) is a recently discovered oncogene implicated in malignant progression of both endocrine and nonendocrine malignancies. Clear cell renal cell carcinoma (ccRCC) is cytogenetically characterized by chromosome 3p deletions that harbor the ccRCC-related von Hippel-Lindau, PBRM1, BAP1, and SETD2 tumor suppressor genes, along with chromosome 5q amplifications where the significance has been unclear. PTTG1 localizes to the chromosome 5q region where amplifications occur in ccRCC. In this study, we report a functional role for PTTG1 in ccRCC tumorigenesis. PTTG1 was amplified in ccRCC, overexpressed in tumor tissue, and associated with high-grade tumor cells and poor patient prognosis. In preclinical models, PTTG1 ablation reduced tumorigenesis and invasion. An analysis of gene expression affected by PTTG1 indicated an association with invasive and metastatic disease. PTTG1-dependent expression of the RhoGEF proto-oncogene ECT2 was observed in a number of ccRCC cell lines. Moreover, ECT2 expression correlated with PTTG1 expression and poor clinical features. Together, our findings reveal features of PTTG1 that are consistent with its identification of an oncogene amplified on chromsome 5q in ccRCC, where it may offer a novel therapeutic target of pathologic significance in this disease. Cancer Res; 72(17); 4361–71. ©2012 AACR.
Biomarker and Pharmacologic Evaluation of the γ-Secretase Inhibitor PF-03084014 in Breast Cancer Models
Authors: Zhang Cathy C. , Pavlicek Adam , Zhang Qin , Lira Maruja E. , Painter Cory L. , Yan Zhengming , Zheng Xianxian , Lee Nathan V. , Ozeck Mark , Qiu Ming , Zong Qing , Lappin Patrick B. , Wong Anthony , Rejto Paul A. , Smeal Tod , Christensen James G. 
Published: July 2012

AbstractPurpose: We aimed to assess the biologic activity of PF-03084014 in breast xenograft models. The biomarkers for mechanism and patient stratification were also explored.Experimental Design: The in vitro and in vivo properties of PF-03084014 were investigated. The mRNA expressions of 40 key Notch pathway genes at baseline or after treatment were analyzed to link with the antitumor efficacy of PF-03084014 in a panel of breast cancer xenograft models.Results: In vitro, PF-03084014 exhibited activity against tumor cell migration, endothelial cell tube formation, and mammosphere formation. In vivo, we observed apoptosis, antiproliferation, reduced tumor cell self-renewal ability, impaired tumor vasculature, and decreased metastasis activity after the treatment of PF-03084014. PF-03084014 treatment displayed significant antitumor activity in 10 of the 18 breast xenograft models. However, the antitumor efficacy in most models did not correlate with the in vitro antiproliferation results in the corresponding cell lines, suggesting the critical involvement of tumor microenvironment during Notch activation. In the tested breast xenograft models, the baseline expressions of the Notch receptors, ligands, and the cleaved Notch1 failed to predict the antitumor response to PF-03084014, whereas several Notch pathway target genes, including HEY2, HES4, and HES3, strongly corresponded with the response with a P value less than 0.01. Many of the best molecular predictors of response were also significantly modulated following PF-03084014 treatment.Conclusions: PF-03084014 showed antitumor and antimetastatic properties via pleiotropic mechanisms. The Notch pathway downstream genes may be used to predict the antitumor activity of PF-03084014 and enrich for responders among breast cancer patients. Clin Cancer Res; 18(18); 5008–19. ©2012 AACR.
Calcium Channel TRPV6 as a Potential Therapeutic Target in Estrogen Receptor–Negative Breast Cancer
Authors: Peters Amelia A. , Simpson Peter T. , Bassett Johnathon J. , Lee Jane M. , Da Silva Leonard , Reid Lynne E. , Song Sarah , Parat Marie-Odile , Lakhani Sunil R. , Kenny Paraic A. , Roberts-Thomson Sarah J. , Monteith Gregory R. 
Published: July 2012

Abstract
Calcium signaling is a critical regulator of cell proliferation. Elevated expression of calcium channels and pumps is a characteristic of some cancers, including breast cancer. We show that the plasma membrane calcium channel TRPV6, which is highly selective for Ca2+, is overexpressed in some breast cancer cell lines. Silencing of TRPV6 expression in a breast cancer cell line with increased endogenous TRPV6 expression leads to a reduction in basal calcium influx and cellular proliferation associated with a reduction in DNA synthesis. TRPV6 gene amplification was identified as one mechanism of TRPV6 overexpression in a subset of breast cancer cell lines and breast tumor samples. Analysis of two independent microarray expression datasets from breast tumor samples showed that increased TRPV6 expression is a feature of estrogen receptor (ER)-negative breast tumors encompassing the basal-like molecular subtype, as well as HER2-positive tumors. Breast cancer patients with high TRPV6 levels had decreased survival compared with patients with low or intermediate TRPV6 expression. Our findings suggest that inhibitors of TRPV6 may offer a novel therapeutic strategy for the treatment of ER-negative breast cancers. Mol Cancer Ther; 11(10); 2158–68. ©2012 AACR.
Risk Score for Intracranial Hemorrhage in Patients With Acute Ischemic Stroke Treated With Intravenous Tissue-Type Plasminogen Activator
Authors: Menon Bijoy K. , Saver Jeffrey L. , Prabhakaran Shyam , Reeves Mathew , Liang Li , Olson DaiWai M. , Peterson Eric D. , Hernandez Adrian F. , Fonarow Gregg C. , Schwamm Lee H. , Smith Eric E. 
Published: July 2012

Background and Purpose—
There are few validated models for prediction of risk of symptomatic intracranial hemorrhage (sICH) after intravenous tissue-type plasminogen activator treatment for ischemic stroke. We used data from Get With The Guidelines–Stroke (GWTG-Stroke) to derive and validate a prediction tool for determining sICH risk.

Methods—
The population consisted of 10 242 patients from 988 hospitals who received intravenous tissue-type plasminogen activator within 3 hours of symptom onset from January 2009 to June 2010. This sample was randomly divided into derivation (70%) and validation (30%) cohorts. Multivariable logistic regression identified predictors of intravenous tissue-type plasminogen activator-related sICH in the derivation sample; model β coefficients were used to assign point scores for prediction.

Results—
sICH within 36 hours was noted in 496 patients (4.8%). Multivariable adjusted independent predictors of sICH were increasing age (17 points), higher baseline National Institutes of Health Stroke Scale (42 points), higher systolic blood pressure (21 points), higher blood glucose (8 points), Asian race (9 points), and male sex (4 points). The C-statistic was 0.71 in the derivation sample and 0.70 in the independent internal validation sample. Plots of observed versus predicted sICH showed good model calibration in the derivation and validation cohorts. The model was externally validated in National Institute of Neurological Disorders and Stroke trial patients with a C-statistic of 0.68.

Conclusions—
The GWTG-Stroke sICH risk “GRASPS” score provides clinicians with a validated method to determine the risk of sICH in patients treated with intravenous tissue-type plasminogen activator within 3 hours of stroke symptom onset.