bluuebunny/crossref_metadata_2025_split huggingface dataset:
Time-dependent magnetization in epitaxial hard magnetic thin films
Authors: Collocott S J , Neu V 
Published: January 2012

Abstract
Time-dependent magnetic behaviour at room temperature is investigated in highly oriented epitaxial hard magnetic thin films. Single-layer films with nominal composition PrCo5 and PrCo7 were studied, along with two SmCo5/Fe/SmCo5 trilayer films, with Fe layer thicknesses of 11 and 16 nm. The films were prepared using pulsed laser deposition on Cr buffered MgO (110) substrates. For the trilayer system, judicious choice of the thickness of the hard (SmCo5) and soft (Fe) magnetic layers results in an exchange-coupled two-phase magnet. All the thin films exhibit switching behaviour, i.e. a near square hysteresis loop, and the details of this behaviour are explored through both measurement of the hysteresis loop, at very slow field sweep rates, and the irreversible susceptibility, χirr. Measurements of the sweep rate dependence of the intrinsic coercivity, and magnetic viscosity on the major hysteresis loop were performed. For each film, three techniques were used to determine the fluctuation field, H
f: from the sweep rate data; from the magnetization relaxation data using the waiting time method; and from S/χirr, where S is the magnetic viscosity coefficient. Differences in the value of H
f determined using the three different techniques, and the equivalence of the three techniques, are discussed. Further insights into the time-dependent behaviour of the magnetization are gained from observations of the spontaneous remagnetization, following dc demagnetization. The study shows the thin films to be of high-stability. Furthermore, it supports the view that magnetization reversal in these materials is most likely an incoherent process, and not a process involving the uniform reversal of a grain. The model of weak pinning provides a useful framework for understanding magnetization processes.
The Effect of a Genetically Reduced Plasma Membrane Protonmotive Force on Vegetative Growth of Arabidopsis
Authors: Haruta Miyoshi , Sussman Michael R. 
Published: January 2012

AbstractThe plasma membrane proton gradient is an essential feature of plant cells. In Arabidopsis (Arabidopsis thaliana), this gradient is generated by the plasma membrane proton pump encoded by a family of 11 genes (abbreviated as AHA, for Arabidopsis H+-ATPase), of which AHA1 and AHA2 are the two most predominantly expressed in seedlings and adult plants. Although double knockdown mutant plants containing T-DNA insertions in both genes are embryonic lethal, under ideal laboratory growth conditions, single knockdown mutant plants with a 50% reduction in proton pump concentration complete their life cycle without any observable growth alteration. However, when grown under conditions that induce stress on the plasma membrane protonmotive force (PMF), such as high external potassium to reduce the electrical gradient or high external pH to reduce the proton chemical gradient, aha2 mutant plants show a growth retardation compared with wild-type plants. In this report, we describe the results of studies that examine in greater detail AHA2’s specific role in maintaining the PMF during seedling growth. By comparing the wild type and aha2 mutants, we have measured the effects of a reduced PMF on root and hypocotyl growth, ATP-induced skewed root growth, and rapid cytoplasmic calcium spiking. In addition, genome-wide gene expression profiling revealed the up-regulation of potassium transporters in aha2 mutants, indicating, as predicted, a close link between the PMF and potassium uptake at the plasma membrane. Overall, this characterization of aha2 mutants provides an experimental and theoretical framework for investigating growth and signaling processes that are mediated by PMF-coupled energetics at the cell membrane.
ArabidopsisUbiquitin Conjugase UBC32 Is an ERAD Component That Functions in Brassinosteroid-Mediated Salt Stress Tolerance
Authors: Cui Feng , Liu Lijing , Zhao Qingzhen , Zhang Zhonghui , Li Qingliang , Lin Baoying , Wu Yaorong , Tang Sanyuan , Xie Qi 
Published: January 2012

AbstractPlants modify their growth and development to protect themselves from detrimental conditions by triggering a variety of signaling pathways, including the activation of the ubiquitin-mediated protein degradation pathway. Endoplasmic reticulum (ER)-associated protein degradation (ERAD) is an important aspect of the ubiquitin-proteasome system, but only a few of the active ERAD components have been reported in plants. Here, we report that the Arabidopsis thaliana ubiquitin-conjugating enzyme, UBC32, a stress-induced functional ubiquitin conjugation enzyme (E2) localized to the ER membrane, connects the ERAD process and brassinosteroid (BR)-mediated growth promotion and salt stress tolerance. In vivo data showed that UBC32 was a functional ERAD component that affected the stability of a known ERAD substrate, the barley (Hordeum vulgare) powdery mildew O (MLO) mutant MLO-12. UBC32 mutation caused the accumulation of bri1-5 and bri1-9, the mutant forms of the BR receptor, BRI1, and these mutant forms subsequently activated BR signal transduction. Further genetic and physiological data supported the contention that UBC32 plays a role in the BR-mediated salt stress response and that BR signaling is necessary for the plant to tolerate salt. Our data indicates a possible mechanism by which an ERAD component regulates the growth and stress response of plants.
Frontal EEG asymmetry moderates the effects of stressful life events on internalizing symptoms in children at familial risk for depression
Authors: Lopez‐Duran Nestor L. , Nusslock Robin , George Charles , Kovacs Maria 
Published: January 2012

AbstractThis study examined whether frontal alpha electroencephalographic (EEG) asymmetry moderates the association between stressful life events and depressive symptoms in children at familial risk for depression. Participants included 135 children ages 6 to 13, whose mothers had either a history of depression or no history of major psychiatric conditions. Frontal EEG was recorded while participants watched emotion‐eliciting films. Symptoms and stressful life events were obtained via the Child Behavior Check List and a clinical interview, respectively. High‐risk children displayed greater relative right lateral frontal activation (F7/F8) than their low‐risk peers during the films. For high‐risk children, greater relative left lateral frontal activation moderated the association between stressful life events and internalizing symptoms. Specifically, greater relative left lateral frontal activation mitigated the effects of stress in at‐risk children.
Effect of meal content on heart rate variability and cardiovascular reactivity to mental stress
Authors: Sauder Katherine A. , Johnston Elyse R. , Skulas‐Ray Ann C. , Campbell Tavis S. , West Sheila G. 
Published: January 2012

AbstractLittle is known about transient effects of foods and nutrients on reactivity to mental stress. In a randomized crossover study of healthy adults (n = 20), we measured heart rate variability (respiratory sinus arrhythmia), blood pressure, and other hemodynamic variables after three test meals varying in type and amount of fat. Measurements were collected at rest and during speech and cold pressor tasks. There were significant postmeal changes in resting diastolic blood pressure (−4%), cardiac output (+18%), total peripheral resistance (−17%), and interleukin‐6 (−27%). Heart rate variability and hemodynamic reactivity to stress was not affected by meal content. We recommend that future studies control for time since last meal and continue to examine effects of meal content on heart rate variability.
Lactoferrin Inhibits Porphyromonas gingivalis Proteinases and Has Sustained Biofilm Inhibitory Activity
Authors: Dashper Stuart G. , Pan Yu , Veith Paul D. , Chen Yu-Yen , Toh Elena C. Y. , Liu Sze Wei , Cross Keith J. , Reynolds Eric C. 
Published: January 2012

ABSTRACT

Porphyromonas gingivalis
is a bacterial pathogen associated with chronic periodontitis that results in destruction of the tooth's supporting tissues. The major virulence determinants of
P. gingivalis
are its cell surface Arg- and Lys-specific cysteine proteinases, RgpA/B and Kgp. Lactoferrin (LF), an 80-kDa iron-binding glycoprotein found in saliva and gingival crevicular fluid, is believed to play an important role in innate immunity. In this study, bovine milk LF displayed proteinase inhibitory activity against
P. gingivalis
whole cells, significantly inhibiting both Arg- and Lys-specific proteolytic activities. LF inhibited the Arg-specific activity of purified RgpB, which lacks adhesin domains, and also inhibited the same activity of the RgpA/Kgp proteinase-adhesin complexes in a time-dependent manner, with a first-order inactivation rate constant (
k
inact
) of 0.023 min
−1
and an inhibitor affinity constant (

K
I

) of 5.02 μM. LF inhibited
P. gingivalis
biofilm formation by >80% at concentrations above 0.625 μM. LF was relatively resistant to hydrolysis by
P. gingivalis
cells but was cleaved into two major polypeptides (53 and 33 kDa) at R
284
to S
285
, as determined by in-source decay mass spectrometry; however, these polypeptides remained associated with each other and retained inhibitory activity. The biofilm inhibitory activity of LF against
P. gingivalis
was not attributed to direct antibacterial activity, as LF displayed little growth inhibitory activity against planktonic cells. As the known RgpA/B and Kgp inhibitor
N
-α-
p
-tosyl-
l
-lysine chloromethylketone also inhibited
P. gingivalis
biofilm formation, the antibiofilm effect of LF may at least in part be attributable to its antiproteinase activity.
In Vitro
Antibacterial Activity of the Ceftazidime-Avibactam (NXL104) Combination against Pseudomonas aeruginosa Clinical Isolates
Authors: Levasseur Premavathy , Girard Anne-Marie , Claudon Monique , Goossens Herman , Black Michael T. , Coleman Kenneth , Miossec Christine 
Published: January 2012

ABSTRACT

The β-lactamase inhibitor avibactam (NXL104) displays potent inhibition of both class A and C enzymes. The
in vitro
antibacterial activity of the combination ceftazidime-avibactam was evaluated against a clinical panel of
Pseudomonas aeruginosa
isolates. Avibactam offered efficient protection from hydrolysis since 94% of isolates were susceptible to ceftazidime when combined with 4 μg/ml avibactam, compared with 65% susceptible to ceftazidime alone. Ceftazidime-avibactam also demonstrated better antipseudomonal activity than imipenem (82% susceptibility), a common reference treatment.
Cefoxitin as an Alternative to Carbapenems in a Murine Model of Urinary Tract Infection Due to Escherichia coli Harboring CTX-M-15-Type Extended-Spectrum β-Lactamase
Authors: Lepeule Raphaël , Ruppé Etienne , Le Patrick , Massias Laurent , Chau Françoise , Nucci Amandine , Lefort Agnès , Fantin Bruno 
Published: January 2012

ABSTRACT

We investigated the efficiency of the cephamycin cefoxitin as an alternative to carbapenems for the treatment of urinary tract infections (UTIs) due to
Escherichia coli
producing CTX-M-type extended-spectrum β-lactamases. The susceptible, UTI-inducing
E. coli
CFT073-RR strain and its transconjugant CFT073-RR Tc (p
bla
CTX-M-15
), harboring a
bla
CTX-M-15
carrying-plasmid, were used for all experiments. MICs of cefoxitin (FOX), ceftriaxone (CRO), imipenem (IMP), and ertapenem (ETP) for CFT073-RR and CFT073-RR Tc (p
bla
CTX-M-15
) were 4 and 4, 0.125 and 512, 0.5 and 0.5, and 0.016 and 0.032 μg/ml, respectively. Bactericidal activity was similarly achieved
in vitro
against the two strains after 3 h of exposure to concentrations of FOX, IMI, and ETP that were 2 times the MIC, whereas CRO was not bactericidal against CFT073-RR Tc (p
bla
CTX-M-15
). The frequencies of spontaneous mutants of the 2 strains were not higher for FOX than for IMP or ETP. In the murine model of UTIs, mice infected for 5 days were treated over 24 h. Therapeutic regimens in mice (200 mg/kg of body weight every 3 h or 4 h for FOX, 70 mg/kg every 6 h for CRO, 100 mg/kg every 2 h for IMP, and 100 mg/kg every 4 h for ETP) were chosen in order to reproduce the percentage of time that free-drug concentrations above the MIC are obtained in humans with standard regimens. All antibiotic regimens produced a significant reduction in bacterial counts (greater than 2 log
10
CFU) in kidneys and bladders for both strains (
P
< 0.001) without selecting resistant mutants
in vivo
, but the reduction obtained with CRO against CFT073-RR Tc (p
bla
CTX-M-15
) in kidneys was significantly lower than that obtained with FOX. In conclusion, FOX appears to be an effective therapeutic alternative to carbapenems for the treatment of UTIs due to CTX-M-producing
E. coli
.
A Single Chromosome Unexpectedly Links Highly Divergent Isolates of Toxoplasma gondii
Authors: Walzer Katelyn A. , Boyle Jon P. 
Published: January 2012

ABSTRACT

Toxoplasma gondii
is an obligate intracellular parasite that can cause disease in all warm-blooded animals studied to date, including humans. Over a billion people have been infected with this parasite worldwide. In Europe and North America,
Toxoplasma
has a clonal population structure, where only three lineages are highly dominant (strain types I, II, and III). Khan et al. [

mBio
2(6)
: e00228-11, 2011

] have carried out phylogenetic analyses on a large number of diverse strains from outside of these lineages and found evidence for a significant split between the clonal North American/European lineages and those in South America. In contrast to most of the genome, nearly all North American/European strains sampled, and the majority of South American strains sampled, harbored at least portions of a monomorphic chromosome Ia (Ia*). In contrast to previous models, these data suggest that the monomorphic haplotype originated in South America and migrated to the North. These authors propose that South American haplotype 12 was a precursor to modern-day type II, while South American haplotypes 6 and 9 crossed with haplotype 12 to give rise to the type I and III lineages, respectively. However, the findings reported by Khan et al. complicate the origin of chromosome Ia, since there are members of haplotypes 9 and 12 with nearly complete versions of Ia* and members of haplotypes 6 and 12 with over 50% of Ia*. This unexpected finding raises exciting new questions about how an entire common chromosome can be found within strains that are highly divergent at most other genomic loci.
The ABC of handover: a qualitative study to develop a new tool for handover in the emergency department
Authors: Farhan Maisse , Brown Ruth , Woloshynowych Maria , Vincent Charles 
Published: January 2012

ObjectivesThis study identifies best practice for shift handover and introduces a new tool used to hand over clinical and operational issues at the end of a shift in the emergency department (ED).MethodsLiterature review, semi-structured interviews and observations of handover were used to develop a standardised process for handover. Participants were ED middle grades, consultants and senior nurses. Interviews were used to identify agreed best practice and derive a tool to classify the information into relevant sections.ResultsInterviews identified a variety of perceived current deficits in handover including a lack of standardised practice and structure. Participants provided examples of poor handover that were thought to have led to adverse events; these included delay in investigations and treatment for patients who were handed over with brief or inaccurate information. There was wide variation in the understanding of the meaning and purpose of shift handover, and differences were apparent according to the level of experience of the middle grades interviewed. The experts' responses were used to reach a unifying ‘best practice’ for the content of handover. This was then grouped under ABCDE headings to develop the ABC of handover tool.ConclusionsA simple tool was developed to provide the basis for medical shift handover, which includes clinical and operational information necessary for efficiency and organisation of the next shift. The ABC of handover classifies shift information to be handed over under the ABCDE headings, which are easy to remember and highly relevant to emergency medicine.
Management of subarachnoid hemorrhage with intracerebral hematoma: clipping and clot evacuation versus coil embolization followed by clot evacuation
Authors: Reyes Kenneth de los , Patel Aman , Bederson Joshua B , Frontera Jennifer A 
Published: January 2012

BackgroundAneurysmal subarachnoid hemorrhage (SAH) with associated intracerebral hemorrhage (ICH) is often treated with concomitant surgical clipping and ICH evacuation. The aim of this study was to determine if aneurysm coiling followed by ICH evacuation is a viable alternative treatment.MethodsA retrospective review was conducted between July 2000 and March 2009 of patients with aneurysmal SAH plus ICH (>30 ml or with midline shift >5 mm) who underwent aneurysm repair (either coiling or clipping) and craniotomy for ICH evacuation. Demographic and radiographic criteria, time to aneurysm protection, length of stay (LOS), treatment complications, discharge disposition and 3 month functional outcome were compared between groups.ResultsOf 18 SAH+ICH patients, 10 underwent aneurysm coiling followed by ICH evacuation and eight underwent clipping with ICH evacuation. Compared with clipped patients, coiled patients had a lower Glasgow Coma Scale score (median 5.5 vs 7.5), higher ICH score (median 3 vs 2), worse modified Fisher score (median 4 vs 3) and higher rate of herniation at presentation (50% vs 25%). Median time to aneurysm protection was shorter in coiled patients (299 vs 885 min, p<0.001). Comparing coiled with clipped patients, rates of death (30% vs 25%), poor outcome (70% vs 50%), median ICU LOS (20 vs 22 days), median hospital LOS (27 vs 29 days) and total median direct costs ($64 537 vs $61 243) were similar, as were complication rates (all p>0.05).ConclusionsCoiling followed by ICH evacuation is associated with faster time to aneurysm protection and similar outcome, LOS and cost as clipping and evacuation. This may be a viable alternative to clipping and ICH evacuation.
HPV-related information sharing and factors associated with US men's disclosure of an HPV test result to their female sexual partners
Authors: Marhefka Stephanie L , Daley Ellen M , Anstey Erica Hesch , Vamos Cheryl A , Buhi Eric R , Kolar Stephanie , Giuliano Anna R 
Published: January 2012

ObjectivesPrevalence of human papillomavirus (HPV) is high in both men and women, yet men have seldom been involved in HPV education/prevention programmes, and their disclosure of known HPV infection has rarely been studied. This analysis sought to determine factors associated with men's HPV test result disclosure and HPV-related information sharing with partners.MethodsFrom 2007 to 2010, men enrolled in a psychosocial study of responses to HP testing who reported having a female main sexual partner (N=251) completed surveys including questions about HPV test results, disclosure of HPV test results to partner(s), relationship characteristics and stigma (for those who reported HPV-positive results) approximately 3 weeks after receiving an HPV test result. Logistic regression was conducted to determine factors associated with disclosure of HPV test results in cross-sectional analysis.ResultsMost men disclosed their test results to a main partner (82%). Self-reported HPV-negative test result, a high school education and a higher commitment to a sexual partner were significantly associated with increased disclosure in multivariable analysis. Men who disclosed (vs those who did not) were significantly more likely to provide their partners with HPV-related information. Among men who disclosed to their main partner, nearly half reported that partner asked them questions about HPV.ConclusionsResults from this study highlight the critical role that men who are symptomatic for, who are tested for or who are vaccinated against HPV can play in educating their sexual partners, independent of whether they actually disclose their test results.
Preventing Cancer with Vaccines: Progress in the Global Control of Cancer
Authors: Kane Mark A. 
Published: January 2012

Abstract
The cancer control community is largely unaware of great advances in the control of major human cancers with vaccines, including the dramatic control of hepatocellular (liver) cancer with hepatitis B virus (HBV) vaccine, now used routinely in more than 90% of countries. The biotechnology revolution has given us a new generation of highly effective vaccines against major global killers, global funding for immunization is orders of magnitude higher than ever before, and the vaccine delivery infrastructure has improved very significantly even in the poorest countries. Liver cancer is the greatest cause of cancer deaths in men of sub-Saharan Africa and much of Asia. Even in highly endemic countries such as China, the prevalence of HB surface antigen carriers has fallen from 10% to 1%–2% in immunized cohorts of children, and liver cancer has already fallen dramatically in Taiwanese children. The Global Alliance for Vaccines and Immunization (now called the GAVI Alliance) has greatly expedited this success by providing HBV vaccine free for five years in most of the world's 72 poorest countries. HBV vaccination can serve as a model for the global control of human papillomavirus (HPV)–related cervical and other cancers with HPV vaccines. Cervical cancer is the greatest cause of cancer death in women in many developing countries; HPV vaccines are highly effective in preventing HPV infection and precancerous lesions in women, and the quadrivalent vaccine also prevents genital warts in men and women and precancerous anal lesions in men. HPV is causing a growing proportion of oropharyngeal cancers, and HPV-related noncervical cancers (penile, anal, and oropharyngeal) may exceed the incidence of cervical cancer within a decade in industrial countries, where cervical screening is effective, causing reevaluation of male HPV immunization. In developing countries, few women are screened for cervical precancerous lesions, making immunization even more important. Currently, 26 primarily industrial countries routinely immunize girls with HPV vaccine, and GAVI will begin to accept applications in 2012 to fund vaccine in developing countries that can deliver the vaccine and if GAVI can negotiate an acceptable price (one manufacturer has already offered a price of $5 per dose). Cancer Prev Res; 5(1); 24–29. ©2012 AACR.