bluuebunny/crossref_metadata_2025 huggingface dataset:
Migraine and motion sickness independently contribute to visual discomfort
Authors: Conforto AB , Lois LA , Amaro E , Paes AT , Ecker C , Young WB , Gamarra LF , Peres MFP
Published: June 2009

The objective of this study was to evaluate, in patients with migraine and healthy volunteers, with and without a history of motion sickness, the degree of discomfort elicited by drifting striped patterns. Eighteen healthy volunteers (HV) and 30 migraine patients participated in the study. Discomfort was greater in migraine patients than in HV, and in individuals with a history of motion sickness than in those without, but the effect of history of migraine was independent of history of motion sickness. Generalized Estimating Equations models for binary correlated data revealed that these differences did not depend on levels of duty cycle, spatial and temporal frequencies. Visual discomfort in migraine patients was associated with worse performance. There was a significant correlation between median degree of discomfort across conditions and number of migraine attacks in the past month. Discomfort to drifting striped patterns may be related to central sensitization in migraine patients.
Cutaneous lymphoid hyperplasia (pseudolymphoma) in tattoos: a case series of seven patients
Authors: Kluger N , Vermeulen C , Moguelet P , Cotten H , Koeb MH , Balme B , Fusade T
Published: June 2009

Background  Cutaneous lymphoid hyperplasia (CLH or pseudolymphoma) is considered a rare complication occurring in tattoos. We analysed the demographics, clinical features, histological aspects, allergy tests, outcome and therapeutic data of CLH in tattoos performed by a professional in a series of patients.

Methods  We conducted a retrospective chart review of seven patients managed in private practice of dermatology all over France from 2001 to 2007.

Results  Reactions occurred within 2 years after tattooing, were non‐specific (pruritus, swelling, infiltration) and mainly restricted to red. Photosensitivity was noted in two cases. Histology was characteristic of pseudolymphoma with a T‐cell predominance in all cases. Surgery (2 cases) and laser removal (2 cases, CO2 and QS‐532 nm) were efficient, while local corticosteroids were not. One patient had spontaneous clinical remission after 2 years of evolution.

Conclusions  This is the largest series of CLH occurring in tattoos. This delayed hypersensitivity reaction may be underestimated and triggered by a specific immunogenic compound of the ink. Its management remains difficult.
Tobacco carcinogen induces microglial activation and subsequent neuronal damage
Authors: Ghosh Debapriya , Mishra Manoj Kumar , Das Sulagna , Kaushik Deepak Kumar , Basu Anirban
Published: June 2009

4‐Methylnitrosamino‐1‐(3‐pyridyl)‐1‐butanone (NNK) is a tobacco‐specific procarcinogen. We have investigated whether NNK causes inflammatory upheaval in the brain by activation of resident microglia and astrocyte and result in bystander neuronal damage. We have carried out the work in bothin vitroandin vivomodels. We have found that treatment with NNK causes significant activation of mouse microglial (BV2) cell line as evident by increase in reactive oxygen species and nitric oxide level. Western blot analysis has showed increase in proinflammatory signaling proteins, proinflammatory effector proteins, and other stress‐related proteins. Interestingly, increased levels of proinflammatory cytokines like interleukin (IL)‐6, tumor necrosis factor‐α, monocyte chemoattractant protein 1 (MCP1), and IL‐12p70 are also detected. Work from ourin vivostudies has demonstrated similar increase in proinflammatory signaling and effector molecules along with the proinflammatory cytokine levels, following NNK treatment. Immunohistochemical staining of the brain sections of NNK‐treated mice reveals massive microglial and astrocyte activation along with distinct foci of neuronal damage. Bothin vitroandin vivoresults provide strong indication that NNK causes significant upheaval of the inflammatory condition of brain and inflicts subsequent neuronal damage.
CORRELATION BETWEEN SPECTRAL, SEM/EDX AND ELECTROCHEMICAL PROPERTIES OF MAYA BLUE: A CHEMOMETRIC STUDY*
Authors: DOMÉNECH A. , DOMÉNECH‐CARBÓ M. T. , VÁZQUEZ DE AGREDOS PASCUAL M. L.
Published: June 2009

Visible spectra, composition from SEM/EDX and solid‐state electrochemical data are correlated for a set of 12 Maya Blue samples from different archaeological sites of Campeche and Yucatán (Mexico). In addition to indigo and dehydroindigo, indirubin and other possibly indigo‐type compounds can be detected in Maya Blue samples. Application of hierarchical cluster analysis techniques allows similarity relationships to be established between samples from different sites, confirming prior results which suggest that the preparation of Maya Blue pigment evolved with time during the Maya culture following a ramified scheme.
Bowel resection for severe endometriosis: An Australian series of 177 cases
Authors: WILLS Hannah J. , REID Geoffrey D. , COOPER Michael J. W. , TSALTAS Jim , MORGAN Matthew , WOODS Rodney J.
Published: June 2009

Background: Colorectal resection for severe endometriosis has been increasingly described in the literature over the last 20 years.

Aims: To describe the experiences of three gynaecological surgeons who perform radical surgery for colorectal endometriosis.

Methods: The records of three surgeons were reviewed. Relevant information was extracted and complied into a database.

Results: One hundred and seventy‐seven women were identified as having undergone surgery between February 1997 and October 2007. The primary reason for presentation was pain in the majority of women (79%). Eighty‐one segmental resections were performed, 71 disc excisions, ten appendicectomies and multiple procedures in ten women. The majority of procedures (81.4%) were performed laparoscopically. Histology confirmed the presence of disease in 98.3% of cases. A further 124 procedures to remove other sites of endometriosis were conducted, along with an additional 44 procedures not primarily for endometriosis. A total of 16 unintended events occurred.

Conclusions: Our study adds to the growing body of literature describing colorectal resection for severe endometriosis. Overall, the surgery appeared to be well tolerated, demonstrating the role for this surgery.
Differences between tree species seedling and adult altitudinal distribution in mountain forests during the recent warm period (1986–2006)
Authors: Lenoir Jonathan , Gégout Jean‐Claude , Pierrat Jean‐Claude , Bontemps Jean‐Daniel , Dhôte Jean‐François
Published: June 2009

Spatial fingerprints of climate change on tree species distribution are usually detected at latitudinal or altitudinal extremes (arctic or alpine tree line), where temperatures play a key role in tree species distribution. However, early detection of recent climate change effects on tree species distribution across the overall temperature gradient remains poorly explored. Within French mountain forests, we investigated altitudinal distribution differences between seedling (≤50 cm tall and >1 yr old) and adult (>8 m tall) life stages for 17 European tree taxa, encompassing the entire forest elevation range from lowlands to the subalpine vegetation belt (50–2250 m a.s.l.) and spanning the latitudinal gradient from northern temperate to southern Mediterranean forests. We simultaneously identified seedlings and adults within the same vegetation plots. These twin observations gave us the equivalent of exactly paired plots in space with seedlings reflecting a response to the studied warm period (1986–2006) and adults reflecting a response to a former and cooler period. For 13 out of 17 species, records of the mean altitude of presence at the seedling life stage are higher than that at the adult life stage. The low altitudinal distribution limit of occurrences at the seedling life stage is, on average, 29 m higher than that at the adult life stage which is significant. The high altitudinal distribution limit also shows a similar trend but which is not significant. Complementary analyses using modelling techniques and focusing on the optimum elevation (i.e. the central position inside distribution ranges) have confirmed differences between life stages altitudinal distribution. Seedlings optima are mostly higher than adults optimum, reaching, on average, a 69 m gap. This overall trend showing higher altitudinal distribution at the seedling life stage in comparison to the adult one suggests a main driver of change highly related to elevation, such as climate warming that occurs during the studied period. Other drivers of change that could play an important role across elevation or act at more specific scales are also discussed as potential contributors to explain our results.
Combined PER2 and CRY1 expression predicts outcome in chronic lymphocytic leukemia
Authors: Eisele Lewin , Prinz Robert , Klein‐Hitpass Ludger , Nückel Holger , Lowinski Kerstin , Thomale Jürgen , Moeller Lars C. , Dührsen Ulrich , Dürig Jan
Published: June 2009

The objective of this study was to confirm previous results regarding the differential expression and prognostic significance of the circadian gene CRY1 in chronic lymphocytic leukemia (CLL) patients and its relationship with the expression of other circadian genes and well‐established prognostic markers. We also aimed to investigate whether the peripheral circadian machinery may be deregulated in CLL cells. The expression of CRY1, PER1, and PER2 was determined by real‐time reverse transcriptase polymerase chain reaction (RT‐PCR) in 116 CLL patients. The expression at sequential time points over a 24‐h period was measured in six CLL patients and six normal donors. We confirmed the differential expression of CRY1 in ZAP‐70+/CD38+ and ZAP‐70−/CD38− CLL samples. Subgroups formed according to CRY1 expression levels differed significantly in time to treatment. This difference was even more pronounced for subgroups stratified by a CRY1 : PER2 expression ratio and the ratio was an independent prognostic marker in a multivariate model. Furthermore, our data indicate disturbances in the periodic expression of circadian genes in CLL cells. Because of their role in the expression of cell cycle‐related and DNA‐damage response genes, we suggest that the deregulated expression of circadian genes may be linked to the molecular pathogenesis of CLL.
Use of Illicit Drugs and Erectile Dysfunction Medications and Subsequent HIV Infection Among Gay Men in Sydney, Australia
Authors: Prestage Garrett , Jin Fengyi , Kippax Susan , Zablotska Iryna , Imrie John , Grulich Andrew
Published: June 2009

Introduction

Use of illicit drugs and oral erectile dysfunction medications (OEM) have been associated with risk behavior among gay men.

Aim

To determine the effects of illicit drugs and OEM as risk factors for HIV seroconversion in a community-based cohort of HIV-negative homosexually active men in Sydney, Australia.

Main Outcome Measures

Drug use in the previous 6 months and at the most recent sexual encounter; Most recent occasions of unprotected and protected anal intercourse; HIV-positive diagnosis.

Methods

From June 2001 to June 2007, participants were followed up with 6-monthly detailed behavioral interviews and annual testing for HIV. Detailed information about sexual, drug-using and other behavior was collected.

Results

Among 1,427 participants enrolled, 53 HIV seroconverters were identified by June 2007. At baseline, 62.7% reported using illicit drugs in the previous 6 months, including 10.7% who reported at least weekly use. Illicit drug use was associated with unprotected anal intercourse with casual partners (P < 0.001). Use of illicit drugs was associated with increased risk of HIV infection at a univariate level, and this risk increased with greater frequency of use. This was also true of the use of OEM. Use of each type of illicit drug was included in multivariate analysis, and after controlling for sexual risk behaviors, only use of OEM remained significantly predictive of HIV infection (Hazard ratios [HR] = 1.75, CI = 1.31–2.33, P < 0.001), although amyl nitrite was of borderline significance (HR = 1.26, CI = 0.98–1.62, P = 0.074).

Conclusion

The association between drug use and increased risk of HIV infection was strongest for drugs used specifically to enhance sexual pleasure, particularly OEM. The risk of infection was substantially increased when both OEM and methamphetamine were used. Within more “adventurous” gay community subcultures, the interconnectedness of sexual behavior and drug use may be key to understanding HIV risk and is an appropriate priority in HIV-prevention efforts in this population.
Laser Doppler Imaging of Genital Blood Flow: A Direct Measure of Female Sexual Arousal
Authors: Waxman Samantha E. , Pukall Caroline F.
Published: June 2009

Introduction

Female sexual arousal is a challenging construct to measure, partly because of the subtle nature of its indicators, vaginal lubrication and genital swelling. As a result, many instruments have been used in an attempt to accurately measure it; however, problems are associated with each. Furthermore, the relationship between subjective and physiological indicators of arousal appears to be influenced by the instrument used to measure physiological arousal. Specifically, instruments measuring physiological arousal internally yield lower correlations between measures of physiological and subjective arousal than instruments examining the external genitals. Laser Doppler imaging (LDI) is a direct measure of external genital blood flow.

Aim

The purpose of this study was to investigate the usefulness of LDI for measuring genital blood flow in women in response to erotic visual stimuli, and to explore the relationship between physiological and subjective sexual arousal.

Method

Sixty-five participants watched three 15-minute films during LDI scanning.

Main Outcome Measures

Two nature films (measuring acclimatization and baseline blood flow levels) and one randomly assigned experimental film (erotic, anxiety, humor, or neutral) were used. Participants rated their level of subjective arousal following the third film.

Results

Results indicated a significant effect of film condition on genital blood flow, P < 0.001, with the erotic condition differing significantly from the other three conditions. In terms of the relationship between physiological and subjective sexual arousal, physiological arousal was significantly predicted by subjective ratings of sexual arousal (P < 0.001).

Conclusions

LDI appears to be able to differentiate blood flow during erotic and nonerotic conditions. In addition, physiological sexual arousal was significantly predicted by women’s reported subjective sexual arousal. These findings suggest that LDI is a useful instrument for measuring female sexual arousal, and that women may be more aware of their level of physiological arousal than previously assumed.
Who is the 40-Year-Old Virgin and Where Did He/She Come From? Data from the National Survey of Family Growth
Authors: Eisenberg Michael L. , Shindel Alan W. , Smith James F. , Lue Tom F. , Walsh Thomas J.
Published: June 2009

Introduction

Little is known about young and middle aged adults who have never engaged in sexual intercourse. Individuals who have not engaged in sexual activity may theoretically have diminished overall quality of life, as recent evidence suggests that sexual activity may be related to overall health status in adults.

Aim

We sought to identify factors related to sexual abstinence in young and middle-aged adults.

Methods

We analyzed data from the male and female sample of the 2002 National Survey of Family Growth to examine sexual abstinence among unmarried participants aged 25–45 (men: N = 2,469; women: N = 5,120).

Main Outcome Measures

Multivariable logistic regression modeling was used to test for independent associations between demographic, medical, and anthropometric variables and abstinence while adjusting for confounding and mediating variables.

Results

A total of 122 (13.9%) men aged 25–45 reported never having had sex, representing approximately 1.1 million American men in this age cohort. Among female participants, a total of 104 (8.9%) women aged 25–45 reported never having sex, representing approximately 800,000 American women in this age cohort. Both men and women who reported that they attend religious services one or more times per week were more likely to be sexually abstinent, independent of their specific religious beliefs. Virgin status was also significantly associated with drinking alcohol within the past year. While a college degree in women predicted virginity, education was not associated with virginity in men. Men showed lower rates of sexual abstinence if they reported having spent time in prison or serving in the military.

Conclusions

Amongst young adults, sexual abstinence does not appear to be mediated by health status, anthropometric measures, or age. Attending religious services and avoidance of alcohol consumption are associated with virginity in adults. Other factors associated with abstinence differ between genders and merit further study.
Is the HR 8799 extrasolar system destined for planetary scattering?
Authors: Goździewski Krzysztof , Migaszewski Cezary
Published: June 2009

The recent discovery of a three-planet extrasolar system of HR 8799 by Marois et al. is a breakthrough in the field of the direct imaging. This great achievement raises questions on the formation and dynamical stability of the system, because Keplerian fits to astrometric data disrupt during ∼0.2 Myr. We search for stable, self-consistent N-body orbits with the so-called GAMP (genetic algorithm with MEGNO penalty) method that incorporates stability constraints into the optimization algorithm. Our searches reveal only small regions of stable motions in the phase space of three-planet, coplanar configurations. Most likely, if the planetary masses are in 10 MJ range, they may be stable only if the planets are involved in two- or three-body mean motion resonances (MMRs). We found that 80 per cent systems found by GAMP that survived 30 Myr backwards integrations, eventually become unstable after 100 Myr. It could mean that the HR 8799 system undergo a phase of planet–planet scattering. We test a hypothesis that the less certain detection of the innermost object is due to a blending effect. In such a case, two-planet best-fitting systems are mostly stable, on quasi-circular orbits and close to the 5:2 MMR, resembling the Jupiter–Saturn pair.
The scaleheight of NGC 1058 measured from its Hi power spectrum
Authors: Dutta Prasun , Begum Ayesha , Bharadwaj Somnath , Chengalur Jayaram N.
Published: June 2009

We have measured the H i power spectrum of the nearly face-on spiral galaxy NGC 1058 from radio-interferometric observations using a visibility based estimator. The power spectrum is well fitted by two different power laws P(U) =AUα, one with α=−2.5 ± 0.6 at small length-scales (600 pc to 1.5 kpc) and another with α=−1.0 ± 0.2 at large length-scales (1.5–10.0 kpc). We interpret this change in the slope of the power spectrum as a transition from 3D turbulence at small length-scales to 2D turbulence in the plane of the galaxy's disc at large length-scales. We use the observed break in the power spectrum to estimate the galaxy's scaleheight, which we find to be 490 ± 90 pc.
Multidimensional Linking for Tests with Mixed Item Types
Authors: Yao Lihua , Boughton Keith
Published: June 2009

Numerous assessments contain a mixture of multiple choice (MC) and constructed response (CR) item types and many have been found to measure more than one trait. Thus, there is a need for multidimensional dichotomous and polytomous item response theory (IRT) modeling solutions, including multidimensional linking software. For example, multidimensional item response theory (MIRT) may have a promising future in subscale score proficiency estimation, leading toward a more diagnostic orientation, which requires the linking of these subscale scores across different forms and populations. Several multidimensional linking studies can be found in the literature; however, none have used a combination of MC and CR item types. Thus, this research explores multidimensional linking accuracy for tests composed of both MC and CR items using a matching test characteristic/response function approach. The two‐dimensional simulation study presented here used real data‐derived parameters from a large‐scale statewide assessment with two subscale scores for diagnostic profiling purposes, under varying conditions of anchor set lengths (6, 8, 16, 32, 60), across 10 population distributions, with a mixture of simple versus complex structured items, using a sample size of 3,000. It was found that for a well chosen anchor set, the parameters recovered well after equating across all populations, even for anchor sets composed of as few as six items.
Serious complications of cosmetic NewColorIris implantation
Authors: Anderson Justin E. , Grippo Tomas M. , Sbeity Zaher , Ritch Robert
Published: June 2009

Acta Ophthalmol. 2010: 88: 700–704

Purpose:  This case report describes serious postoperative complications and markedly elevated intraocular pressure (IOP) associated with the NewColorIris cosmetic implant.

Methods:  We report an interventional case series of two patients who suffered multiple complications after NewColorIris implantation carried out in Panama. Assessment included visual acuity, photography, endothelial cell count and anterior segment optical coherence tomography (OCT) when possible.

Results:  Both patients presented with endothelial cell loss, uveitis, pigment dispersion and elevated IOP. Anterior segment OCT demonstrated irregularities in the position and configuration of the implants within the anterior chamber with resultant areas of implant–iris and implant–endothelial contact. One patient had acute postoperative hyphaema that resolved with anterior chamber tissue plasminogen activator injection. Both patients required explantation OU, one eye has required trabeculectomy, and one eye with bullous keratopathy is being evaluated for Descemet’s stripping endothelial keratoplasty.

Conclusions:  Implantation of the NewColorIris cosmetic implant can lead to serious complications including hyphaema, uncontrolled IOP, severe endothelial cell loss, bullous keratopathy and anterior uveitis. Explantation may lead to improvement, but permanent damage to the trabecular meshwork and corneal endothelium persists.
Biomass and seed yields of big bluestem, switchgrass, and intermediate wheatgrass in response to manure and harvest timing at two topographic positions
Authors: LEE DOKYOUNG , OWENS VANCE N. , BOE ARVID , KOO BON‐CHEOL
Published: June 2009

A principle attribute of perennial grasses for biomass energy is the potential for high yields on marginal lands. Objectives of this study were to compare biomass and seed production of intermediate wheatgrass (Thinopyrum intermedium [Host] Barkworth and D.R. Dewey), big bluestem (Andropogon gerardii Vitman), and switchgrass (Panicum virgatum L.) as affected by harvest timing and manure application on two topographic positions (footslope and backslope). Footslope is the hillslope position that forms the inclined surface at the base of a slope and backslope forms the steepest, middle position of the hillslope. Grasses were harvested for biomass at anthesis (summer), after a killing frost (autumn), or the following spring after overwintering in the field. Seed was harvested at maturity during 2003 and 2004. Two rates of beef cattle (Bos taurus L.) manure (target rates of 0 and 150 kg total‐N ha−1) were surface applied annually. Maximum annual biomass yield ranged from 4.4 to 5.2, 2.7 to 4.2, and 3.7 to 5.6 Mg ha−1 for intermediate wheatgrass, big bluestem, and switchgrass, respectively. Biomass yields were not different between fall and spring harvest treatments. Biomass yields of big bluestem and switchgrass at the backslope position were 86% and 96% of biomass yields at the footslope position with normal precipitation, respectively. Manure application increased biomass yield approximately 30% during the second year on both topographic positions. The highest seed yield was obtained from intermediate wheatgrass, followed by switchgrass and big bluestem. Utilizing these management practices in our environment, it appears that switchgrass and big bluestem could be allowed to overwinter in the field without suffering appreciable loss of biomass.
Biodiesel fuel production via transesterification of oils using lipase biocatalyst
Authors: XIAO MAN , MATHEW SINI , OBBARD JEFFREY PHILIP
Published: June 2009

Biodiesel has gained widespread importance in recent years as an alternative, renewable liquid transportation fuel. It is derived from natural triglycerides in the presence of an alcohol and an alkali catalyst via a transesterification reaction. To date, transesterification based on the use of chemical catalysts has been predominant for biodiesel production at the industrial scale due to its high conversion efficiency at reasonable cost. Recently, biocatalytic transesterification has received considerable attention due to its favorable conversion rate and relatively simple downstream processing demands for the recovery of by‐products and purification of biodiesel. Biocatalysis of the transesterification reaction using commercially purified lipase represents a major cost constraint. However, more cost‐effective techniques based on the immobilization of both extracellular and intracellular lipases on support materials facilitate the reusability of the catalyst. Other variables, including the presence of alcohol, glycerol and the activity of water can profoundly affect lipase activity and stability during the reaction. This review evaluates the current status for lipase biocatalyst‐mediated production of biodiesel, and identifies the key parameters affecting lipase activity and stability. Pioneer studies on reactor‐based lipase conversion of triglycerides are presented.
The ecology and agronomy of Miscanthus sinensis, a species important to bioenergy crop development, in its native range in Japan: a review
Authors: STEWART J. RYAN , TOMA YO , FERNÁNDEZ FABIÁN G. , NISHIWAKI AYA , YAMADA TOSHIHIKO , BOLLERO GERMÁN
Published: June 2009

Among several candidate perennial taxa, Miscanthus×giganteus has been evaluated and promoted as a promising bioenergy crop. Owing to several limitations, however, of the sterile hybrid, both at the taxon and agronomic production levels, other options need to be explored to not only improve M. ×giganteus, which was originally collected in Japan, but to also consider the development of other members of its genus, including Miscanthus sinensis, as bioenergy crops. Indeed, there is likely much to be learned and applied to Miscanthus as a bioenergy crop from the long history of intensive interaction between humans and M. sinensis in Japan, which in some regions of the country spans several thousand years. Combined with its high amount of genetic variation, stress tolerance, biotic interactions with fauna, and function as a keystone species in diverse grasslands and other ecosystems within its native range, the unique and extensive management of M. sinensis in Japan as a forage grass and building material provides agronomists, agroecologists, and plant breeders with the capability of better understanding this species in terms of potential contribution to bioenergy crop development. Moreover, the studies described in this review may serve as a platform for future research of Miscanthus as a bioenergy crop in other parts of the world.
Antibacterial Properties and Mode of Action of a Short Acyl-Lysyl Oligomer
Authors: Zaknoon Fadia , Sarig Hadar , Rotem Shahar , Livne Liran , Ivankin Andrey , Gidalevitz David , Mor Amram
Published: June 2009

We investigated the potency, selectivity, and mode of action of the oligo-acyl-lysine (OAK) NC12-2β12, which was recently suggested to represent the shortest OAK sequence that retains nonhemolytic antibacterial properties. A growth inhibition assay against a panel of 48 bacterial strains confirmed that NC12-2β12exerted potent activity against gram-positive bacteria while exhibiting negligible hemolysis up to at least 100 times the MIC. Interestingly, NC12-2β12demonstrated a bacteriostatic mode of action, unlike previously described OAKs that were bactericidal and essentially active against gram-negative bacteria only. The results of various experiments with binding to model phospholipid membranes correlated well with those of the cytotoxicity experiments and provided a plausible explanation for the observed activity profile. Thus, surface plasmon resonance experiments performed with model bilayers revealed high binding affinity to a membrane composition that mimicked the plasma membrane of staphylococci (global affinity constant[Kapp], 3.7 × 106M−1) and significantly lower affinities to mimics ofEscherichia colior red blood cell cytoplasmic membranes. Additional insertion isotherms and epifluorescence microscopy experiments performed with model Langmuir monolayers mimicking the outer leaflet of plasma membranes demonstrated the preferential insertion of NC12-2β12into highly anionic membranes. Finally, we provide mechanistic studies in support of the view that the bacteriostatic effect resulted from a relatively slow process of plasma membrane permeabilization involving discrete leakage of small solutes, such as intracellular ATP. Collectively, the data point to short OAKs as a potential source for new antibacterial compounds that can selectively affect the growth of gram-positive bacteria while circumventing potential adverse effects linked to lytic compounds.
Effect of Subinhibitory Concentrations of Antibiotics on Intrachromosomal Homologous Recombination in
Escherichia coli
Authors: López Elena , Blázquez Jesús
Published: June 2009

Subinhibitory concentrations of some antibiotics, such as fluoroquinolones, have been reported to stimulate mutation and, consequently, bacterial adaptation to different stresses, including antibiotic pressure. In
Escherichia coli
, this stimulation is mediated by alternative DNA polymerases induced via the SOS response. Sublethal concentrations of the fluoroquinolone ciprofloxacin have been shown to stimulate recombination between divergent sequences in
E. coli
. However, the effect of ciprofloxacin on recombination between homologous sequences and its SOS dependence have not been studied. Moreover, the possible effects of other antibiotics on homologous recombination remain untested. The aim of this work was to study the effects of sublethal concentrations of ciprofloxacin and 10 additional antibiotics, including different molecular families with different molecular targets, on the rate of homologous recombination of DNA in
E. coli
. The antibiotics tested were ciprofloxacin, ampicillin, ceftazidime, imipenem, chloramphenicol, tetracycline, gentamicin, rifampin (rifampicin), trimethoprim, fosfomycin, and colistin. Our results indicate that only ciprofloxacin consistently stimulates the intrachromosomal recombinogenic capability of homologous sequences in
E. coli
. The ciprofloxacin-based stimulation occurs at concentrations and times that apparently do not dramatically compromise the viability of the whole population, and it is dependent on RecA and partially dependent on SOS induction. One of the main findings of this work is that, apart from quinolone antibiotics, none of the most used antibiotics, including trimethoprim (a known inducer of the SOS response), has a clear side effect on homologous recombination in
E. coli
. In addition to the already described effects of some antibiotics on mutagenicity, DNA transfer, and genetic transformability in naturally competent species, the effect of increasing intrachromosomal recombination of homologous DNA sequences can be uniquely ascribed to fluoroquinolones, at least for
E. coli
.
AFN-1252, a FabI Inhibitor, Demonstrates a Staphylococcus-Specific Spectrum of Activity
Authors: Karlowsky James A. , Kaplan Nachum , Hafkin Barry , Hoban Daryl J. , Zhanel George G.
Published: June 2009

AFN-1252, a potent inhibitor of enoyl-acyl carrier protein reductase (FabI), inhibited all clinical isolates of
Staphylococcus aureus
(
n
= 502) and
Staphylococcus epidermidis
(
n
= 51) tested, including methicillin (meticillin)-resistant isolates, at concentrations of ≤0.12 μg/ml. In contrast, AFN-1252 was inactive (MIC
90
, >4 μg/ml) against clinical isolates of
Streptococcus pneumoniae
, beta-hemolytic streptococci,
Enterococcus
spp.,
Enterobacteriaceae
, nonfermentative gram-negative bacilli, and
Moraxella catarrhalis
. These data support the continued development of AFN-1252 for the treatment of patients with resistant staphylococcal infections.
The Manganese Transporter MntH Is a Critical Virulence Determinant forBrucella abortus2308 in Experimentally Infected Mice
Authors: Anderson Eric S. , Paulley James T. , Gaines Jennifer M. , Valderas Michelle W. , Martin Daniel W. , Menscher Evan , Brown Timothy D. , Burns Colin S. , Roop R. Martin
Published: June 2009

The gene designated BAB1_1460 in theBrucella abortus2308 genome sequence is predicted to encode the manganese transporter MntH. Phenotypic analysis of an isogenicmntHmutant indicates that MntH is the sole high-affinity manganese transporter in this bacterium but that MntH does not play a detectable role in the transport of Fe2+, Zn2+, Co2+, or Ni2+. Consistent with the apparent selectivity of the corresponding gene product, the expression of themntHgene inB. abortus2308 is repressed by Mn2+, but not Fe2+, and this Mn-responsive expression is mediated by a Mur-like repressor. TheB. abortus mntHmutant MWV15 exhibits increased susceptibility to oxidative killing in vitro compared to strain 2308, and a comparative analysis of the superoxide dismutase activities present in these two strains indicates that the parental strain requires MntH in order to make wild-type levels of its manganese superoxide dismutase SodA. TheB. abortus mntHmutant also exhibits extreme attenuation in both cultured murine macrophages and experimentally infected C57BL/6 mice. These experimental findings indicate that Mn2+transport mediated by MntH plays an important role in the physiology ofB. abortus2308, particularly during its intracellular survival and replication in the host.
Leishmania majorPhosphoglycans Influence the Host Early Immune Response by Modulating Dendritic Cell Functions
Authors: Liu Dong , Kebaier Chahnaz , Pakpour Nazzy , Capul Althea A. , Beverley Stephen M. , Scott Phillip , Uzonna Jude E.
Published: June 2009

The precise role ofLeishmaniaglycoconjugate molecules including phosphoglycans (PGs) and lipophosphoglycan (LPG) on host cellular responses is still poorly defined. Here, we investigated the interaction ofLeishmania major LPG2null mutant (lpg2−), which lacks both PGs and LPG, with dendritic cells (DCs) and the subsequent early immune response in infected mice. Surprisingly, the absence of phosphoglycans did not influence expression pattern of major histocompatibility complex class II (MHC II), CD40, CD80, and CD86 on DCs in vitro and in vivo. However,lpg2−L. majorinduced significantly higher production of interleukin-12p40 (IL-12p40) by infected bone marrow-derived DCs (BMDCs) than wild-type (WT) parasites in vitro. Furthermore, the production of IL-12p40 by draining lymph node cells fromlpg2−mutant-infected mice was higher than those from WTL. major-infected mice. In model antigen presentation experiments, DCs fromlpg2−mutant-infected mice induced more gamma interferon (IFN-γ) and IL-2 production byLeishmania-specific T cells than those from WT-infected mice. Lymphocytes isolated from mice infected for 3 days withlpg2−parasites produce similar levels of IFN-γ, but significantly less IL-4 and IL-10 than WT controls. Decreased IL-4 production was also seen in another general PG-deficient mutant lacking the Golgi UDP-galactose transporters (lpg5A−lpg5B−), but not with thelpg1−mutant lacking only LPG, thereby implicating PGs generally in the reduction of IL-4 production. Thus,LeishmaniaPGs influence host early immune response by modulating DC functions in a way that inhibits antigen presentation and promotes early IL-4 response, and their absence may impact the balance between Th1 and Th2 responses.
Unique Roles of DosT and DosS in DosR Regulon Induction and
Mycobacterium tuberculosis
Dormancy
Authors: Honaker Ryan W. , Leistikow Rachel L. , Bartek Iona L. , Voskuil Martin I.
Published: June 2009

In
Mycobacterium tuberculosis
, the sensor kinases DosT and DosS activate the transcriptional regulator DosR, resulting in the induction of the DosR regulon, which is important for anaerobic survival and perhaps latent infection. The individual and collective roles of these sensors have been postulated biochemically, but their roles in vivo have remained unclear. This work demonstrates distinct and additive roles for each sensor during anaerobic dormancy. Both sensors are necessary for wild-type levels of DosR regulon induction, and concomitantly, full induction of the regulon is required for wild-type anaerobic survival. In the anaerobic model, DosT plays an early role, responding to hypoxia. DosT then induces the regulon and with it DosS, which sustains and further induces the regulon. DosT then loses its functionality as oxygen becomes limited, and DosS alone maintains induction of the genes from that point forward. Thus,
M. tuberculosis
has evolved a system whereby it responds to hypoxic conditions in a stepwise fashion as it enters an anaerobic state.
SPACETIME AS A DEFORMABLE SOLID
Authors: TAHIM M. O. , LANDIM R. R. , ALMEIDA C. A. S.
Published: June 2009

In this letter we discuss the possibility of treating the spacetime by itself as a kind of deformable body for which we can define a fundamental lattice, just like atoms in crystal lattices. We show three signs pointing in that direction. We simulate the spacetime manifold by a very specific congruence of curves and use the Landau–Raychadhuri equation to study the behavior of such a congruence. The lattice appears because we are forced to associate to each curve of the congruence a sort of fundamental "particle". The world-lines of these particles should be identified with the congruence fulfilling the spacetime manifold. The conclusion is that when describing the deformations of the spacetime the Einstein equations emerge and the spacetime metric should be treated as a secondary (not fundamental) object of the theory.
PROBING THE STATISTIC IN THE COSMIC MICROWAVE BACKGROUND
Authors: GHAHRAMANYAN T. , MIRZOYAN S. , POGHOSIAN E. , YEGORIAN G.
Published: June 2009

Kolmogorov's statistic is used for the analysis of properties of perturbations in the Cosmic Microwave Background signal. We obtain the maps of the Kolmogorov stochasticity parameter for W and V band temperature data of WMAP which are differently affected by the Galactic disk radiation and then model datasets with various statistics of perturbations. The analysis shows that the Kolmogorov's parameter can be an efficient tool for the separation of Cosmic Microwave Background from the contaminating radiations due to their different statistical properties.
MLD INTERFERENCE CANCELER FOR M-ARRAY QAM SIGNALS APPLIED TO FWA SYSTEMS
Authors: YOSHIOKA HIROSHI , SHIRATO YUSHI , WATANABE KAZUJI , NAKANO KEISUKE , SENGOKU MASAKAZU
Published: June 2009

We propose a maximum likelihood detection (MLD) interference canceler applied to fixed wireless access (FWA) systems. There are two major degradation factors associated with a conventional MLD canceler. One is the decision error caused by constellation ambiguity when distinguishing between desired and interference signal components for M-array QAM signals. The novelty of our interference canceler is its use of our antenna switching technique to reduce constellation ambiguity. The phase difference between the desired and interference signals received by the main and sub antennas depends on the path gap between desired and interference signal transmitters to the two receiving antennas. Cancelation performance is improved by using the phase difference that maximizes the separation of the received signal points. Two key points of the proposed technique are the path gap and the threshold for antenna switching. The second degradation factor is the degradation in interference signal replica accuracy caused by the phase rotation of the interference signals. An automatic phase control (APC) circuit estimates and compensates for this phase rotation, enabling the interference canceler with APC to achieve excellent bit error rate (BER) performance. Computer simulations show that our interference canceler improves the BER performance.
EFFECT OF LIGHT IRRADIATION ON ELECTRIC-FIELD-INDUCED RESISTANCE SWITCHING PHENOMENON IN PLANAR VO2/c-Al2O3 STRUCTURE
Authors: MOHAMAD NURUL EZREENA , OKIMURA KUNIO , SAKAI JOE
Published: June 2009

A simple device of VO 2 film with two terminal electrodes revealed current jump phenomena at certain applied voltage. In this study, we investigated the effect of light irradiation on the electric field-induced resistance switching phenomenon. Based on changes of current–voltage characteristics under light irradiation, we discussed the effect of light irradiation on this device.
EFFECT OF CAPPING LAYER ON InxGa1-xN QUANTUM DOTS GROWN USING NNAD METHOD BY MOCVD
Authors: SONG HEON , NAVAMATHAVAN R. , JEONG SEONG-MUK , LEE SEON-HO , KIM JIN-SU , SEOL KYEONG-WON , KIM DONG-WOOK , LEE CHEUL-RO
Published: June 2009

In x Ga 1-x N quantum dots (QDs) were grown on GaN epitaxy using nitridation of nano-alloyed droplet (NNAD) method by metal-organic chemical vapor deposition (MOCVD) system. Before the In x Ga 1-x N QDs formation, In + Ga droplets were initially formed by the flow of TMI and TMG, which acts as a nucleation seed for the QDs growth. Density of the alloy droplets was increased with the increasing flow rate; however, droplet size was scarcely changed about 100–200 nm by flow rate. And In x Ga 1-x N QDs size can be easily changed by controlling the nitridation time or various factors. Also, the influence of GaN capping layer on the properties of In x Ga 1-x N QDs was discussed.
APPLICATIONS OF NANOIMPRINT LITHOGRAPHY FOR BIOCHEMICAL AND NANOPHOTONIC STRUCTURES USING SU-8
Authors: LU BINGRUI , XIE SHEN-QI , WAN JING , YANG RONG , SHU ZHEN , QU XIN-PING , LIU RAN , CHEN YIFANG , HUQ EJAZ
Published: June 2009

Nanoimprint lithography (NIL) technology has aroused great interests in both academia and industry due to its high resolution, low-cost, and high-volume nanopatterning capability. And as an expoxy resin-based negative amplified photoresist, SU-8 is an ideal candidate for NIL because of its low-glass-transition temperature, low-volume shrinkage coefficient, and good optical properties. In this reviewing paper, we highlight the major technical achievements in NIL on epoxy resin and its applications for bio- and nanophotonic structures. NIL was also applied for the duplication of imprint templates, originally fabricated by e-beam lithography (EBL) followed by reactive ion etch (RIE), using a SU-8/ SiO 2/PMMA tri-layer technique. And nanoimprint properties were systematically investigated for optimization. The developed nanoimprint process for different applications indicates promising industrial potentials in the next generation lithography resolution.
SINGLE STEP SYNTHESIS OF MAGNESIUM FERRITE NANOCRYSTALLITES AND SOME OF ITS CHARACTERISTICS
Authors: THANT AYE AYE , SREEKANTAN SRIMALA , KAUNG PHO , ITOH MITSURU , OTHMAN RADZALI , FAUZI M. N. AHMAD
Published: June 2009

The present study elucidates the synthesis of magnesium ferrite magnetic nanocrystallites via hydroxylation–condensation reaction followed by an auto-combustion process. Nanocrystallites with diameter of 3–7 nm were successfully formed via this method. The ignition temperature of the redox reaction was apparently improved to 200°C by the modification of the pH of the metal aqueous solution. The crystallite size was altered by varying the hydrolysis parameters. The XRD analysis of the as-synthesized powder confirms the formation of a single-phase MgFe 2 O 4 spinel structure. Importantly, the crystalline particles were obtained at low temperature without further calcination. The thermodynamic behavior of the precursor was characterized by DTA-TG. TEM observations showed the morphology and crystal structure of the nanocrystallites.
Composing expressive runtime security policies
Authors: Bauer Lujo , Ligatti Jay , Walker David
Published: June 2009

Program monitors enforce security policies by interposing themselves into the control flow of untrusted software whenever that software attempts to execute security-relevant actions. At the point of interposition, a monitor has authority to permit or deny (perhaps conditionally) the untrusted software's attempted action. Program monitors are common security enforcement mechanisms and integral parts of operating systems, virtual machines, firewalls, network auditors, and antivirus and antispyware tools.

Unfortunately, the runtime policies we require program monitors to enforce grow more complex, both as the monitored software is given new capabilities and as policies are refined in response to attacks and user feedback. We propose dealing with policy complexity by organizing policies in such a way as to make them composable, so that complex policies can be specified more simply as compositions of smaller subpolicy modules. We present a fully implemented language and system called Polymer that allows security engineers to specify and enforce composable policies on Java applications. We formalize the central workings of Polymer by defining an unambiguous semantics for our language. Using this formalization, we state and prove an uncircumventability theorem which guarantees that monitors will intercept all security-relevant actions of untrusted software.
Empirical evaluation of a nesting testability transformation for evolutionary testing
Authors: McMinn Phil , Binkley David , Harman Mark
Published: June 2009

Evolutionary testing is an approach to automating test data generation that uses an evolutionary algorithm to search a test object's input domain for test data. Nested predicates can cause problems for evolutionary testing, because information needed for guiding the search only becomes available as each nested conditional is satisfied. This means that the search process can overfit to early information, making it harder, and sometimes near impossible, to satisfy constraints that only become apparent later in the search. The article presents a testability transformation that allows the evaluation of all nested conditionals at once. Two empirical studies are presented. The first study shows that the form of nesting handled is prevalent in practice. The second study shows how the approach improves evolutionary test data generation.
Bilingually Motivated Word Segmentation for Statistical Machine Translation
Authors: Ma Yanjun , Way Andy
Published: June 2009

We introduce a bilingually motivated word segmentation approach to languages where word boundaries are not orthographically marked, with application to Phrase-Based Statistical Machine Translation (PB-SMT). Our approach is motivated from the insight that PB-SMT systems can be improved by optimizing the input representation to reduce the predictive power of translation models. We firstly present an approach to optimize the existing segmentation of both source and target languages for PB-SMT and demonstrate the effectiveness of this approach using a Chinese--English MT task, that is, to measure the influence of the segmentation on the performance of PB-SMT systems. We report a 5.44% relative increase in Bleu score and a consistent increase according to other metrics. We then generalize this method for Chinese word segmentation without relying on any segmenters and show that using our segmentation PB-SMT can achieve more consistent state-of-the-art performance across two domains. There are two main advantages of our approach. First of all, it is adapted to the specific translation task at hand by taking the corresponding source (target) language into account. Second, this approach does not rely on manually segmented training data so that it can be automatically adapted for different domains.