bluuebunny/crossref_metadata_2025 huggingface dataset:
Current-induced spin torque resonance of magnetic insulators affected by field-like spin-orbit torques and out-of-plane magnetizations
Authors: Chiba Takahiro , Schreier Michael , Bauer Gerrit E. W. , Takahashi Saburo
Published: February 2015

The spin-torque ferromagnetic resonance (ST-FMR) in a bilayer system consisting of a magnetic insulator such as Y3Fe5O12 and a normal metal with spin-orbit interaction such as Pt is addressed theoretically. We model the ST-FMR for all magnetization directions and in the presence of field-like spin-orbit torques based on the drift-diffusion spin model and quantum mechanical boundary conditions. ST-FMR experiments may expose crucial information about the spin-orbit coupling between currents and magnetization in the bilayers.
Simple modeling of readback response based on granular micro-structure
Authors: Jin T. , Muraoka H. , Greaves S. J.
Published: February 2015

Magnetization transitions, readback waveforms, and transition jitter are formulated for Voronoi modeling using error functions. Suitable coefficients for the error functions are provided by the parameters of the granular media, i.e., average grain diameter and grain size distribution. TEM images of real media are used to confirm the fitted results. Random grain positions and uniform switching field distribution are assumed. Readback waveforms for isolated transitions are calculated by reciprocity. The pulse width, T50, is formulated from the medium parameters and readback conditions. An error function with the same T50 and slope at the transition center is a good fit. An analytical expression for jitter noise is presented comprising grain size and track width parameters.
Magnetism and electronic structure of (001)- and (111)-oriented LaTiO3 bilayers sandwiched in LaScO3 barriers
Authors: Weng Yakui , Dong Shuai
Published: February 2015

In this study, the magnetism and electronic structure of LaTiO3 bilayers along both the (001) and (111) orientations are calculated using the density functional theory. The band insulator LaScO3 is chosen as the barrier layer and substrate to obtain the isolating LaTiO3 bilayer. For both the (001)- and (111)-oriented cases, LaTiO3 demonstrates the G-type antiferromagnetism as the ground state, similar to the bulk material. However, the electronic structure is significantly changed. The occupied bands of Ti are much narrower in the (111) case, giving a nearly flat band. As a result, the exchange coupling between nearest-neighbor Ti ions is reformed in these superlattices, which will affect the Néel temperature significantly.
Roles of effective helical ripple rates in nonlinear stability of externally induced magnetic islands
Authors: Nishimura Seiya
Published: February 2015

Magnetic islands are externally produced by resonant magnetic perturbations (RMPs) in toroidal plasmas. Spontaneous annihilation of RMP-induced magnetic islands called self-healing has been observed in helical systems. A possible mechanism of the self-healing is shielding of RMP penetration by helical ripple-induced neoclassical flows, which give rise to neoclassical viscous torques. In this study, effective helical ripple rates in multi-helicity helical systems are revisited, and a multi-helicity effect on the self-healing is investigated, based on a theoretical model of rotating magnetic islands. It is confirmed that effective helical ripple rates are sensitive to magnetic axis positions. It is newly found that self-healing thresholds also strongly depend on magnetic axis positions, which is due to dependence of neoclassical viscous torques on effective helical ripple rates.
A hybrid model for simulation of secondary electron emission in plasma immersion ion implantation under different pulse rise time
Authors: Navab Safa N. , Ghomi H.
Published: February 2015

A hybrid fluid Particle in Cell–Monte Carlo Collision (PiC–MCC) model is presented to study the effect of secondary electron emission on the plasma immersion ion implantation process under different pulse rise time. The model describes the temporal evolution of various parameters of plasma such as ion density, ion velocity, secondary electron density, and secondary electron current for different rise times. A 3D–3 V PiC–MCC model is developed to simulate the secondary electrons which are emitted from the sample surface while the plasma ions and electrons are treated using a 1D fluid model. The simulation results indicate that the secondary electron density and secondary electron current increase as the rise time decreases. The main differences between the results for different rise times are found during the initial phase of the pulse. The results are explained through studying the fundamental parameters of plasma.
The impact of defect scattering on the quasi-ballistic transport of nanoscale conductors
Authors: Esqueda I. S. , Cress C. D. , Cao Y. , Che Y. , Fritze M. , Zhou C.
Published: February 2015

Using the Landauer approach for carrier transport, we analyze the impact of defects induced by ion irradiation on the transport properties of nanoscale conductors that operate in the quasi-ballistic regime. Degradation of conductance results from a reduction of carrier mean free path due to the introduction of defects in the conducting channel. We incorporate scattering mechanisms from radiation-induced defects into calculations of the transmission coefficient and present a technique for extracting modeling parameters from near-equilibrium transport measurements. These parameters are used to describe degradation in the transport properties of nanoscale devices using a formalism that is valid under quasi-ballistic operation. The analysis includes the effects of bandstructure and dimensionality on the impact of defect scattering and discusses transport properties of nanoscale devices from the diffusive to the ballistic limit. We compare calculations with recently published measurements of irradiated nanoscale devices such as single-walled carbon nanotubes, graphene, and deep-submicron Si metal-oxide-semiconductor field-effect transistors.
Ultrafast pump-probe force microscopy with nanoscale resolution
Authors: Jahng Junghoon , Brocious Jordan , Fishman Dmitry A. , Yampolsky Steven , Nowak Derek , Huang Fei , Apkarian Vartkess A. , Wickramasinghe H. Kumar , Potma Eric Olaf
Published: February 2015

We perform time-resolved pump-probe microscopy measurements by recording the local force between a sharp tip and the photo-excited sample as a readout mechanism for the material's nonlinear polarization. We show that the photo-induced force is sensitive to the same excited state dynamics as measured in an optical pump-probe experiment. Ultrafast pump-probe force microscopy constitutes a non-optical detection technique with nanoscale resolution that pushes pump-probe sensitivities close to the realm of single molecule studies.
Fluctuation of heat current in Josephson junctions
Authors: Virtanen P. , Giazotto F.
Published: February 2015

We discuss the statistics of heat current between two superconductors at different temperatures connected by a generic weak link. As the electronic heat in superconductors is carried by Bogoliubov quasiparticles, the heat transport fluctuations follow the Levitov–Lesovik relation. We identify the energy-dependent quasiparticle transmission probabilities and discuss the resulting probability density and fluctuation relations of the heat current. We consider multichannel junctions, and find that heat transport in diffusive junctions is unique in that its statistics is independent of the phase difference between the superconductors.
Cetacean strandings in South Australia (1881–2008)
Authors: Segawa Tomoyo , Kemper Catherine
Published: February 2015

Long-term monitoring of cetacean strandings is essential for good management. This study updates previous summaries for South Australia by adding up to 20 years of comprehensive data, including results of necropsy examinations. A total of 1078 records were examined. Thirty-one species were recorded: 9 (7% of records) mysticetes, 22 (88%) odontocetes and the rest (5%) unidentified. The number of species new to South Australia did not reach an asymptote, with potential for at least five additional species. Small cetaceans were more frequently recorded after 1990, possibly due to increased reporting effort. Stranding records increased markedly after 1970. Records for all species occurred year-round. Beaked whales stranded primarily during January–April, baleen whales during July–January and common dolphins during February–May. Geographic hotspots were identified and related to upwelling and reporting effort. A necropsy program since 1990 resulted in 315 of 856 records being assigned to a circumstance of death, with anthropogenic circumstances accounting for 42% of these. Known Entanglement (21%, 66 of 315) and Probable Entanglement (12%, 37 of 315) were the most recorded anthropogenic circumstances of death. Future research correlating strandings with oceanographic/climatic conditions may help to explain the documented patterns but first the effects of reporting effort need to be accounted for.
Using a Laboratory‐Based Growth Model to Estimate Mass‐ and Temperature‐Dependent Growth Parameters across Populations of Juvenile Chinook Salmon
Authors: Perry Russell W. , Plumb John M. , W. Huntington Charles
Published: February 2015

To estimate the parameters that govern mass‐ and temperature‐dependent growth, we conducted a meta‐analysis of existing growth data from juvenile Chinook Salmon Oncorhynchus tshawytscha that were fed an ad libitum ration of a pelleted diet. Although the growth of juvenile Chinook Salmon has been well studied, research has focused on a single population, a narrow range of fish sizes, or a narrow range of temperatures. Therefore, we incorporated the Ratkowsky model for temperature‐dependent growth into an allometric growth model; this model was then fitted to growth data from 11 data sources representing nine populations of juvenile Chinook Salmon. The model fit the growth data well, explaining 98% of the variation in final mass. The estimated allometric mass exponent (b) was 0.338 (SE = 0.025), similar to estimates reported for other salmonids. This estimate of b will be particularly useful for estimating mass‐standardized growth rates of juvenile Chinook Salmon. In addition, the lower thermal limit, optimal temperature, and upper thermal limit for growth were estimated to be 1.8°C (SE = 0.63°C), 19.0°C (SE = 0.27°C), and 24.9°C (SE = 0.02°C), respectively. By taking a meta‐analytical approach, we were able to provide a growth model that is applicable across populations of juvenile Chinook Salmon receiving an ad libitum ration of a pelleted diet.

Received May 20, 2014; accepted December 4, 2014
Effects of phytochemicals on in vitro anti-inflammatory activity of Bifidobacterium adolescentis
Authors: Kawabata Kyuichi , Kato Yuri , Sakano Taiken , Baba Nobuyuki , Hagiwara Kota , Tamura Akira , Baba Seigo , Natsume Midori , Ohigashi Hajime
Published: February 2015

Probiotics have been shown to improve the condition of not only the human gastrointestinal tract but also the entire body. We found that quercetin enhances the anti-inflammatory activity of Bifidobacterium adolescentis, which is abundant in human intestines. Here, we assessed whether certain phytochemicals could enhance the anti-inflammatory activity of B. adolescentis. Bifidobacteria were anaerobically cultured with phytochemicals for 3 h, and the anti-inflammatory activity of the supernatants was estimated by testing their ability to inhibit nitric oxide (NO) production by lipopolysaccharide-stimulated RAW264 macrophages. Of the 55 phytochemicals tested, phloretin, (+)-taxifolin, and (−)-epigallocatechin gallate as well as quercetin-3-O-glucoside and quercetin-4′-O-glucoside were similar to quercetin in promoting NO suppression by B. adolescentis. In addition, the phytochemicals excluding quercetin increased the concentrations of lactic and acetic acids in the co-culture supernatants. These results suggest that some phytochemicals may activate the anti-inflammatory function of B. adolescentis.
Introduction of an antifungal stewardship programme targeting high-cost antifungals at a tertiary hospital in Cambridge, England
Authors: Micallef C. , Aliyu S. H. , Santos R. , Brown N. M. , Rosembert D. , Enoch D. A.
Published: February 2015

Background

Antifungal stewardship aims to promote the optimal use of antifungals through the careful selection of agents based on patient profile, target organism, toxicity, costs and the likelihood of emergence and spread of resistance.

Methods

We report on an observational prospective 12 month study conducted by an antifungal stewardship team targeting the use of echinocandins (caspofungin and micafungin), voriconazole and liposomal amphotericin B in a tertiary referral hospital in the UK.

Results

One-hundred-and-seventy-three patients were reviewed on 294 occasions. Clinical advice was given and implemented during review of 45 (88.2%) of micafungin prescriptions, 70 (78.7%) of those receiving voriconazole, 78 (62.4%) of those receiving liposomal amphotericin B and 3 (27.3%) of those receiving caspofungin. Except for voriconazole, nearly half of all treatments reviewed were stopped or changed. This study found that a crude cost saving of ∼£180 000 in antifungal drugs was generated compared with the previous year.

Conclusions

Using a multidisciplinary team, antifungal stewardship can achieve significant improvements in patient management and it may reduce costs.
Comparison of Hybrid Fixation to Dual Plating for Both-Bone Forearm Fractures in Older Children
Authors: Cai Leyi , Wang Jianshun , Du Shenghu , Zhu Shaoyu , Wang Te , Lu Di , Chen Hua
Published: February 2015

When operative stabilization of forearm fractures in older children is necessary, the optimal method of fixation is controversial. This study compared the radiographic and functional outcomes of dual plating to a hybrid fixation construct with elastic intramedullary nailing of the radius and plate fixation of the ulna of forearm fractures in children aged between 10 and 16 years. Nineteen patients were treated using a hybrid fixation construct and 13 patients were treated with dual plating fixation. The 2 groups were compared retrospectively according to perioperative data and patient outcome measures. The hybrid fixation construct group had 19, with a mean age of 13.3 years (range, 10–16 years) and the dual plate group had 13 patients, with a mean age of 12.9 years (range, 10–16 years). Groups were similar for sex, arm injured, and fracture location. Duration of surgery and tourniquet use was significantly shorter in the hybrid fixation construct group. There was no significant difference in either time to union or Price scores for function evaluation between the 2 groups. Complication rates were also similar between groups, with 1 ulna delayed unions, 1 superficial infection at entry of nail in hybrid fixation construct group, and 1 ulna delayed unions in the dual plating group. Hybrid fixation, using open reduction and internal fixation with a plate-and-screw construct on the ulna and closed reduction and elastic intramedullary fixation of the ulna, is an acceptable method for treating both-bone diaphyseal forearm fractures in skeletally immature patients aged 10–16 years.
Halomicroarcula salina sp. nov., isolated from a marine solar saltern
Authors: Zhang Wen-Jiao , Cui Heng-Lin
Published: February 2015

Halophilic archaeal strain YGHS18T was isolated from the Yinggehai marine solar saltern near Shanya city of Hainan Province, China. Cells from the strain were observed to be pleomorphic rods, stained Gram-negative, and formed red-pigmented colonies on solid media. Strain YGHS18T was found to be able to grow at 20–50 °C (optimum 37 °C), with 0.9–4.8 M NaCl (optimum 2.1 M) and at pH 5.5–9.0 (optimum pH 7.0). The cells lysed in distilled water and the minimum NaCl concentration to prevent cell lysis was found to be 0.9 M. The major polar lipids of the strain were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, glucosyl mannosyl glucosyl diether and a diglycosyl diether (DGD-2). Strain YGHS18T possessed two heterogeneous 16S rRNA genes (rrnA and rrnB) and both were related to those of members of the genera

Haloarcula

(93.1–96.9 % sequence similarity) and

Halomicroarcula

(92.7–96.1 % similarity). The rrnA gene (orthologous gene) of strain YGHS18T clustered phylogenetically with members of the genus

Halomicroarcula

while the rrnB gene formed a paraphyly with members of the genera

Halomicroarcula

and

Haloarcula

. The rpoB′ gene of strain YGHS18T was related phylogenetically to species of the genera

Halomicroarcula

(91.6–92.7 % sequence similarity) and

Haloarcula

(91.5–92.4 % similarity). EF-2 gene analysis revealed that strain YGHS18T was related phylogenetically to species of the genus

Halomicroarcula

(92.2–92.9 % sequence similarity) rather than to those of the genus

Haloarcula

(90.9–91.7 % similarity). The DNA G+C content of strain YGHS18T was determined to be 64.5 mol%. The phenotypic, chemotaxonomic and phylogenetic properties suggested that strain YGHS18T ( = CGMCC 1.12128T = JCM 18369T) represents a novel species of the genus

Halomicroarcula

, for which the name Halomicroarcula salina sp. nov. is proposed.
Sex hormones in male psoriasis patients and their correlation with the Psoriasis Area and Severity Index
Authors: Cemil Bengu C. , Cengiz Fatma P. , Atas Hatice , Ozturk Gulfer , Canpolat Filiz
Published: February 2015

Modulation of psoriasis severity by estradiol during pregnancy, menstruation and menopause has been investigated previously. The correlation between sex hormones and Psoriasis Area Severity Index (PASI) has not been studied in male psoriasis patients. We investigated serum sex hormones in male psoriasis patients compared with healthy controls and correlated these findings with PASI. Estradiol, testosterone, follicle‐stimulating hormone (FSH) and luteinizing hormone (LH) levels were measured in 47 male patients with psoriasis and 20 healthy controls. Patients with psoriasis showed higher body mass index and higher serum levels of FSH and LH relative to healthy controls, although this difference was not statistically significant. However, serum levels of testosterone and estradiol were significantly different between patients with psoriasis and healthy controls. Testosterone was significantly increased in control patients and estradiol was significantly increased among psoriatic patients. A significant inverse correlation was found between estradiol and PASI. Although the role of sex hormones in the pathogenesis of psoriasis has not been demonstrated, this is the first report of an inverse correlation between estradiol and PASI in male patients.
Association of anti‐RNA polymerase III antibody and malignancy in Japanese patients with systemic sclerosis
Authors: Saigusa Ryosuke , Asano Yoshihide , Nakamura Kouki , Miura Shunsuke , Ichimura Yohei , Takahashi Takehiro , Toyama Tetsuo , Taniguchi Takashi , Noda Shinji , Aozasa Naohiko , Akamata Kaname , Sumida Hayakazu , Miyazaki Miki , Tamaki Zenshiro , Yanaba Koichi , Kuwano Yoshihiro , Sato Shinichi
Published: February 2015

Patients with systemic sclerosis (SSc) have an increased risk of malignancy compared with the general population. Recently, SSc patients with anti‐RNA polymerase III antibody have been reported to have an increased risk of malignancy as compared with those with other disease‐specific autoantibodies in US, European and Australian populations. Therefore, we studied the relationship between disease‐specific autoantibodies and malignancy in 261 Japanese SSc patients. The prevalence of malignancy was significantly higher in patients with anti‐RNA polymerase III antibody (7/22, 31.8%) than in those with anti‐topoisomerase I antibody (2/82, 2.4%) and in those with anticentromere antibody (8/137, 5.8%). Importantly, among seven patients with anti‐RNA polymerase III antibody and malignancy, three patients (42.9%) developed malignancy from 6 months before to 12 months after SSc onset. Thus, malignancy complication in Japanese SSc patients with anti‐RNA polymerase III antibody is as high as that in other races, suggesting that SSc patients with anti‐RNA polymerase III antibody share the same pathological process among different ethnic groups.
Major and trace elements in milk and Halloumi cheese as markers for authentication of goat feeding regimes and geographical origin
Authors: Osorio Maria Teresa , Koidis Anastasios , Papademas Photis
Published: February 2015

Sixty samples of milk, Halloumi cheese and local grazing plants (i.e. shrubs) were collected over a year from dairy farms located on three different locations of Cyprus. Major and trace elements were quantified using inductively coupled plasma–atomic emission spectroscopy (ICP‐AES). Milk and Halloumi cheese produced in different geographical locations presented significant differences in the concentration of some of the elements analysed. Principal component analysis showed grouping of samples according to the region of production for both milk and cheese samples. These findings show that the assay of elements can provide useful fingerprints for the characterisation of dairy products.
Mobile Communication and Local Information Flow: Evidence from Distracted Driving Laws
Authors: BROWN NERISSA C. , STICE HAN , WHITE ROGER M.
Published: February 2015

We examine the influence of mobile communication on local information flow and local investor activity using the enforcement of statewide distracted driving restrictions, which are exogenous events that constrain mobile communication while driving. By restricting mobile communication across a potentially sizable set of local individuals, these restrictions could inhibit local information flow and, in turn, the market activity of stocks headquartered in enforcement states. We first document a decline in Google search activity for local stocks when restrictions take effect, suggesting that constraints on mobile communication significantly affect individuals’ information search activity. We further find significant declines in local trading volume when restrictions are enforced. This drop in liquidity is (1) attenuated when laws provide substitutive means of mobile communication and (2) magnified when locals have long car commutes and when their daily commutes overlap with regular exchange hours. Moreover, trading volume suffers the most for local stocks with lower institutional ownership, less analyst coverage, and more intangible information. Additional analyses show lower intraday volume during local commute times when mobile connectivity is constrained. Together, our results suggest that local information and local investors matter in stock markets and that mobile communication is an important mechanism through which these elements operate to affect liquidity and price discovery.
Design of an Optimum Computer Vision‐Based Automatic Abalone (Haliotis discus hannai) Grading Algorithm
Authors: Lee Donggil , Lee Kyounghoon , Kim Seonghun , Yang Yongsu
Published: February 2015

An automatic abalone grading algorithm that estimates abalone weights on the basis of computer vision using 2D images is developed and tested. The algorithm overcomes the problems experienced by conventional abalone grading methods that utilize manual sorting and mechanical automatic grading. To design an optimal algorithm, a regression formula and R2 value were investigated by performing a regression analysis for each of total length, body width, thickness, view area, and actual volume against abalone weights. The R2 value between the actual volume and abalone weight was 0.999, showing a relatively high correlation. As a result, to easily estimate the actual volumes of abalones based on computer vision, the volumes were calculated under the assumption that abalone shapes are half‐oblate ellipsoids, and a regression formula was derived to estimate the volumes of abalones through linear regression analysis between the calculated and actual volumes. The final automatic abalone grading algorithm is designed using the abalone volume estimation regression formula derived from test results, and the actual volumes and abalone weights regression formula. In the range of abalones weighting from 16.51 to 128.01 g, the results of evaluation of the performance of algorithm via cross‐validation indicate root mean square and worst‐case prediction errors of are 2.8 and ±8 g, respectively.
Dissemination of Enterococcus faecalis and Enterococcus faecium in a Ricotta Processing Plant and Evaluation of Pathogenic and Antibiotic Resistance Profiles
Authors: Fernandes Meg da Silva , Fujimoto Graciela , de Souza Leandro Pio , Kabuki Dirce Yorika , da Silva Márcio José , Kuaye Arnaldo Yoshiteru
Published: February 2015

In this work, the sources of contamination by Enterococcus spp. in a ricotta processing line were evaluated. The isolated strains were tested for virulence genes (gelE, cylA,B, M, esp, agg, ace, efaA, vanB), expression of virulence factors (hemolysin and gelatinase), and the resistance to 10 different antibiotics. Enterococcus faecium and Enterococcus faecalis were subjected to discriminatory identification by intergenic spacer region (ITS)‐polymerase chain reaction and sequencing of the ITS region. The results showed that Enterococcus spp. was detected in the raw materials, environment samples and the final product. None of the 107 Enterococcus isolates were completely free from all virulence genes considered. A fraction of 21.5% of the isolates containing all of the genes of the cylA, B, M operon also expressed β‐hemolysis. Most of the isolates showed the gelE gene, but only 9.3% were able to hydrolyze gelatin. In addition, 23.5% of the observed Enterococcus isolates had the vanB gene but were susceptible to vancomycin in vitro. The dissemination of antibiotic‐resistant enterococci was revealed in this study: 19.3% of the E. faecium samples and 78.0% of the E. faecalis samples were resistant to at least one of the antibiotics tested. Sequencing of region discriminated 5 and 7 distinct groups among E. faecalis and E. faecium, respectively. Although some similarity was observed among some of the isolates, all E. faecalis and E. faecium isolates had genetic differences both in the ITS region and in the virulence profile, which makes them different from each other.
Implementing robotic surgery to gynecologic oncology: the first 300 operations performed at a tertiary hospital
Authors: Mäenpää Minna , Nieminen Kari , Tomás Eija , Luukkaala Tiina , Mäenpää Johanna U.
Published: February 2015

Objective

To investigate the initial experience with robotic‐assisted laparoscopic surgery in gynecologic oncology.

Design

A retrospective survey.

Setting

Tertiary referral center.

Population

The first 300 patients operated on using robotic assistance at the Department of Obstetrics and Gynecology of Tampere University Hospital, from March 2009 through January 2013.

Methods

Retrospective patient chart review.

Main outcome measures

The primary outcome measure was the learning curve events, and the complication and conversion rates were secondary outcome measures.

Results

The commonest type of operation was hysterectomy, bilateral salpingoophorectomy and pelvic lymphadenectomy (LH + BSO + PLND, n = 89), followed by the same procedure amended by para‐aortic lymphadenectomy (PALND, n = 74), type II radical hysterectomy (n = 24), and PLND + PALND ± omentectomy (n = 15). A learning curve was most evident for LH + BSO + PLND: whereas the median operative time of all 89 operations was 167 min (range 403–104), it was 260 (range 403–135) and 153 (range 247–104) min in the case of the first and last 20 operations, respectively. The learning curve was short, or 10 procedures. A learning curve was also seen for the preoperative time in the operation room and for the number of lymph nodes harvested. The median blood loss during all 300 operations was 100 mL (range 5–3200). The median postoperative hospital stay was 1 day. The conversion rate was 4.0%, and the complication rate 19.3% (major in 9%).

Conclusion

The learning curve of robotic‐assisted laparoscopic surgery appears to be short, or 10 operations. Robotic‐assisted procedures seem to offer a safe and useful alternative to traditional techniques.
Chorioretinal scars and visual deprivation are common in children with cochlear implants after congenital cytomegalovirus infection
Authors: Teär Fahnehjelm Kristina , Olsson Monica , Fahnehjelm Cecilia , Lewensohn‐Fuchs Ilona , Karltorp Eva
Published: February 2015

Aim

The aim of this study was to compare visual function and ocular characteristics in children with cochlear implants, due to severe hearing impairment caused by the congenital cytomegalovirus (CMV) infection, with control children fitted with cochlear implants due to connexin 26 mutations (Cx26), a genetic cause of hearing impairment.

Methods

We carried out ophthalmological assessments, including visual acuity, ocular alignment, Ocular Motor Score, biomicroscopy and fundus photography, on 26 children with congenital CMV (median age 8.3 years, range 1.4–16.7) and 13 Cx26 controls (median age 5.6 years, range 1.7–12.5).

Results

We found unilateral chorioretinal macular scars that reduced best‐corrected visual acuity ≤0.3 in five (19%) of the children with congenital CMV, but in none of the children with Cx26 (p = 0.15). Ocular motility problems were more common among children with congenital CMV, but the difference was not significant (p = 0.20). The vestibulo‐ocular reflex was more frequently pathological in children with congenital CMV (p = 0.011).

Conclusion

Ocular complications with central chorioretinal scars and ocular motility disturbances were common in children treated with cochlear implants due to severe hearing impairment caused by the congenital CMV infection. Ophthalmological assessments are advisable in such children for early identification, intervention and follow‐up.
Indications and practical implementation of microbiologic diagnostics in patients with chronic wounds
Authors: Schwarzkopf Andreas , Dissemond Joachim
Published: February 2015

Microbiology diagnostics are frequently performed in patients with chronic wounds. However, there is currently a lack of uniformity with respect to indications as well as the practical implementation of such workup. The fact that diagnostic results may be significantly affected by the sampling technique used as well as the preceding (wound) preparation underscores the need for uniform standards, which have been missing so far.

In Germany, bacteriologic wound swabs are routinely performed, particularly with the intent to screen for multiresistant pathogens. For this indication, prior wound cleansing should be avoided, and sampling using the Essen Rotary technique provides a quick and easy‐to‐use option. If there is clinical suspicion of an infection, wound cleansing with sterile saline solution (0.9 %) and/or sterile cotton gauze should be carried out prior to obtaining bacteriologic swabs. While routine diagnostic biopsies are generally not required in chronic wound patients, they may be useful in case of clinically suspected wound infections, particularly in patients with deep ulcerations, diabetic foot syndrome, severe soft tissue infection, or fistula tissue. Moreover, biopsies are indispensable in the microbiology workup of specific pathogens such as mycobacteria, Leishmania, actinomycetes, Nocardia ssp. or molds.
Biotic and abiotic predictors of fungal colonization in grasses of the Colorado Rockies
Authors: Ranelli Luciana B. , Hendricks Will Q. , Lynn Joshua S. , Kivlin Stephanie N. , Rudgers Jennifer A.
Published: February 2015

Aim

Fungal symbionts are ubiquitous in plants and can mitigate abiotic stressors associated with climate change. Predicting fungal symbiont distributions under future climates first requires knowledge of current distributions and their potential drivers.

Location

We documented colonization by fungal symbionts in perennial, cool‐season grasses along altitudinal gradients in the Rocky Mountains of Colorado, USA.

Methods

Across seven replicate altitudinal gradients, spanning c. 1400 vertical meters, we scored fungal colonization for 46 grass species. We documented altitudinal clines in colonization by both above‐ground and below‐ground fungal symbionts for the first time, including localized foliar endophytes (LFE) and systemic endophytes (epichloae) in leaves and arbuscular mycorrhizal fungi (AMF) and dark septate endophytes (DSE) in roots. For a subset of 16 well‐sampled grass species, we used model selection procedures to evaluate the relative importance of geography, edaphic factors and host plant identity. We also assessed the influence of host phylogenetic relatedness and colonization by co‐infecting fungi.

Results

Levels of fungal colonization varied strongly with host plant identity, but the effects of particular host species were not consistent across fungal groups. In addition to the influence of host identity, epichloae colonization declined with elevation and varied with geography (latitude/longitude) and edaphic factors. Geography and collection date were important predictors of LFE colonization, with higher colonization later in the growing season. Colonization estimates for the obligately plant‐associated fungi (epichloae, AMF) were phylogenetically conserved across the grass supertree. Positive correlations between AMF and DSE, which remained even after accounting for host plant relatedness, suggested possible synergisms between these fungal groups.

Main conclusions

Our survey showed greater host specificity in patterns of fungal colonization than prior reports and revealed that different fungal symbiont groups do not share similar drivers. Conserving plant–fungal symbioses under future climates may require unique strategies for different plant species and fungal symbiont types.
Increased frequency of late‐senescent T cells lacking CD127 in chronic hepatitis C disease
Authors: Barathan Muttiah , Mohamed Rosmawati , Saeidi Alireza , Vadivelu Jamuna , Chang Li Y. , Gopal Kaliappan , Ram Mani R. , Ansari Abdul W. , Kamarulzaman Adeeba , Velu Vijayakumar , Larsson Marie , Shankar Esaki M.
Published: February 2015

Background

Hepatitis C virus (HCV) causes persistent disease in ~85% of infected individuals, where the viral replication appears to be tightly controlled by HCV‐specific CD8+ T cells. Accumulation of senescent T cells during infection results in considerable loss of functional HCV‐specific immune responses.

Materials and methods

We characterized the distinct T‐cell phenotypes based on the expression of costimulatory molecules CD28 and CD27, senescence markers PD‐1 and CD57, chronic immune activation markers CD38 and HLA‐DR, and survival marker CD127 (IL‐7R) by flow cytometry following activation of T cells using HCV peptides and phytohemagglutinin.

Results

HCV‐specific CD4+ and CD8+ T cells from chronic HCV (CHC) patients showed increased expression of PD‐1. Furthermore, virus‐specific CD4+ T cells of CHC‐infected subjects displayed relatively increased expression of HLA‐DR and CD38 relative to HCV‐specific CD8+ T cells. The CD4+ and CD8+ T cells from HCV‐infected individuals showed significant increase of late‐differentiated T cells suggestive of immunosenescence. In addition, we found that the plasma viral loads positively correlated with the levels of CD57 and PD‐1 expressed on T cells.

Conclusions

Chronic HCV infection results in increased turnover of late‐senescent T cells that lack survival potentials, possibly contributing to viral persistence. Our findings challenge the prominence of senescent T‐cell phenotypes in clinical hepatitis C infection.
Norepinephrine and corticosterone in the medial prefrontal cortex and hippocampus predict PTSD‐like symptoms in mice
Authors: Kao C.‐Y. , Stalla G. , Stalla J. , Wotjak C. T. , Anderzhanova E.
Published: February 2015

This study measured changes in brain extracellular norepinephrine (NE) and free corticosterone (CORT) levels in a mouse model of post‐traumatic stress disorder and related them to hyperarousal and fear memory retention. To this end, microdialysis in the medial prefrontal cortex (mPFC) and the hippocampus (HPC) of male C57BL/6NCrl mice was performed during an acoustic startle response (ASR) and following an electric foot shock (FS), as well as during an ASR and recall of contextual fear (CF) 1 day later. Changes in ASR‐stimulated NE levels in the mPFC corresponded to ASR 34 days after FS. Changes in basal and ASR‐stimulated extracellular NE levels in the HPC, in contrast, were related to expression of early (day 2) and late (day 34) CF after FS. The increase in extracellular NE levels correlated in a U‐shape manner with arousal levels and CF, thus suggesting a non‐direct relationship. Stress of different modalities/strength (ASR, FS and CF) caused a similar relative increase in free CORT levels both in the mPFC and the HPC. One day after FS, ASR‐induced increases in the CORT content in the mPFC tended to correlate with the FS‐potentiated ASR in a U‐shape manner. Taken together, these data show that the intracerebral increase in free CORT was likely related to an immediate response to stress, whereas NE neurotransmission in the forebrain predicted arousal and CF 1 month after trauma.
Compass Orientation During Dispersal of Freshwater Hatchling Snapping Turtles (Chelydra serpentina) and Blanding's Turtles (Emydoidea blandingii)
Authors: Congdon Justin D. , Pappas Michael J. , Krenz John D. , Brecke Bruce J. , Schlenner Meredith
Published: February 2015

Freshwater turtle hatchlings primarily use visual cues for orientation while dispersing from nests; however, hatchlings rapidly develop a relationship between a sun or geomagnetic compass and a dispersal target that allows them to maintain an established direction of movement when target habitats are not visible. We examined dispersal patterns of hatchling snapping turtles (Chelydra serpentina) and Blanding's turtles (Emydoidea blandingii) dispersing in large arenas in a mowed field and in dense corn. The dispersal of three categories of hatchlings were examined: (1) naïve individuals (no previous dispersal experience), (2) arena‐experienced (limited dispersal experience in arenas in natural habitat), and (3) natural‐experienced hatchling Blanding's turtles (captured after extensive experience dispersing W in natural habitats toward wetlands). Experienced hatchlings were assigned to treatments consisting of having a magnet or a non‐magnetic aluminum sham or nothing glued to their anterior carapace before release in the corn arena. Dispersal patterns of naïve hatchlings of both species were strongly directional in the field arena with visible target horizons and primarily random in the corn arena where typical target horizons were blocked. When released in corn, dispersal patterns were similar for arena‐experienced hatchlings with magnets or shams attached and differed from their prior dispersal headings in the field arena as naïve hatchlings. Natural‐experienced hatchling Blanding's turtles with and without magnets were able to accurately maintain their prior headings to the WNW while dispersing in the field or corn arenas (i.e., the presence of a magnet did not disrupt their ability to maintain their prior heading). Based on the assumption that no other type of compass exists in hatchlings, we conclude that they were not using a geomagnetic compass, but by default were using sun compass orientation to maintain dispersal headings in dense corn where no typical target habitats were visible.
Larval population structure of Engraulis encrasicolus in the Strait of Sicily as revealed by morphometric and genetic analysis
Authors: Cuttitta Angela , Patti Bernardo , Maggio Teresa , Quinci Enza Maria , Pappalardo Anna Maria , Ferrito Venera , De Pinto Vito , Torri Marco , Falco Francesca , Nicosia Aldo , Musco Marianna , Armeri Grazia Maria , Placenti Francesco , Tranchida Giorgio , Mifsud Roberta , Bonanno Angelo , Mazzola Salvatore
Published: February 2015

In order to investigate the larval population structure, specimens of Engraulis encrasicolus larvae from five different locations in the Strait of Sicily were analyzed by means of otolith readings, morphometric and genetic techniques. The distribution of age in day, identified by means of the otolith readings and associated with the oceanographic parameters, was useful to identify possible spawning areas and transport dynamics. The presence of more than one spawning area suggested the possibility that two or more sub‐populations may co‐exist in the study area. The morphometric characteristics were more adequate than genetic parameters to discriminate the different larval groups. The most relevant variables for the separation were the mouth length (ML) and the body diameter (BD). The population structure by means of genetic data reported the presence of two phylogroups co‐occurring among samples in each sampling locations specimens. The pattern of genetic divergence among anchovy larvae in the Strait of Sicily was congruent with previous studies conducted on adult populations present in other Mediterranean areas with different molecular markers. The habitat‐specific nature of the morphological variation and the lack of corresponding genetic variation among larvae from the different locations suggested that the observed differences in morphology could be linked to environmental parameters. The body form differences among different larvae samples could reflect the nutritional status of larvae. In fact, these differences were found among anchovy larvae collected in areas with different oxygen and fluorescence, which is an index of primary productivity and is linked to the availability of food for anchovy larvae.
Cardiac autonomic neuropathy: The hidden cardiovascular comorbidity in elderly patients with chronic obstructive pulmonary disease attending primary care settings
Authors: Rasheedy Doha , Taha Hend M
Published: February 2015

Aim

To quantify the prevalence of chronic comorbidities including cardiac autonomic neuropathy among elderly patients with chronic obstructive pulmonary disease (COPD).

Methods

A cross‐sectional study was carried out on 175 elderly male patients with COPD attending Ain Shams University Hospital, Cairo, Egypt. The comorbidities that might alter cardiac autonomic function in patients with COPD were identified. The patients without reported comorbidities underwent arterial blood gas analysis, pulmonary function tests and autonomic function assessment using cardiovascular reflexes.

Results

A total of 69.14% of the participants presented with comorbidities (group 1), whereas 30.85% of the participants reported no comorbidity (group 2). Among the participants, the most prevalent comorbid diseases were hypertension (34.20%), cor pulmonale (31.42%), ischemic heart disease (20.00%), diabetes (18.28%) and congestive heart failure (13.70%). In group 2, 29.60% and 22.20% of the patients had early and definite cardiac autonomic neuropathy (CAN) respectively. CAN occurred early in the course of the disease with 40.90% of mild COPD cases being affected. The patients with definite CAN had the highest resting heart rate. The presence of CAN was related to hypercapnia, but not hypoxemia or COPD severity.

Conclusion

COPD has a complex spectrum of comorbidities. Cardiac autonomic neuropathy in elderly male patients with COPD correlated with hypercapnia, but not hypoxemia or the disease severity. Geriatr Gerontol Int 2015; 16: 329–335.
Declines in highly active antiretroviral therapy initiation at CD4 cell counts ≤ 200 cells/μL and the contribution of diagnosis of HIV at CD4 cell counts ≤ 200 cells/μL in British Columbia, Canada
Authors: Lourenço L , Samji H , Nohpal A , Chau W , Colley G , Lepik K , Barrios R , Lima V , Hogg RS , Montaner JSG , Kesselring S , Moore DM
Published: February 2015

Objectives

The aim of the study was to examine trends in initiating highly active antiretroviral therapy (HAART) with a CD4 count ≤ 200 cells/μL and the contribution of having a CD4 count ≤ 200 cells/μL at the time of diagnosis to these trends, in British Columbia (BC), Canada.

Methods

We included in the analysis treatment‐naïve BC residents aged ≥ 19 years who initiated HAART from 2003 to 2012. Participants were classified as follows: Group 1: diagnosed and initiated HAART with a CD4 count > 200 cells/μL; Group 2: diagnosed with a CD4 count > 200 cells/μL and initiated HAART with a CD4 count ≤ 200 cells/μL; and Group 3: diagnosed and initiated HAART with a CD4 count ≤ 200 cells/μL. We measured trends in initiating HAART with a CD4 count ≤ 200 cells/μL and used logistic regression models to measure factors associated with initiating HAART with a CD4 count ≤ 200 cells/μL, stratified by having a CD4 count ≤ 200 cells/μL or > 200 cells/μL at the time of diagnosis.

Results

Between 2003 and 2012, 3506 BC residents initiated HAART. Of these, 44% (1558 of 3506) initiated HAART with a CD4 count ≤ 200 cells/μL. This proportion declined from 69% (198 of 287) in 2003 to 21% (81 of 330) in 2012 (P < 0.001). The proportion of those in Group 3 increased from 49% (97 of 198) in 2003 to 69% (56 of 81) in 2012 (P < 0.001). Overall, 56% (1948), 22% (776) and 22% (782) made up Groups 1, 2, and 3, respectively. In adjusted analyses, seeing a specialist was significantly associated with being in Group 3. Using injection drugs and seeing a specialist were associated with being in Group 2.

Conclusions

In recent years, among individuals who ever initiated HAART in BC, being diagnosed with low CD4 cell counts has become a greater contributor to initiating HAART with low CD4 cell counts.
Benefits of task‐shifting HIV care to nurses in terms of health‐related quality of life in patients initiating antiretroviral therapy in rural district hospitals in Cameroon [Stratall Agence Nationale de Recherche sur le SIDA (ANRS) 12110/Ensemble pour une Solidarité Thérapeutique Hospitalière en Réseau (ESTHER) substudy]
Authors: Suzan‐Monti M , Blanche J , Boyer S , Kouanfack C , Delaporte E , Bonono R‐C , Carrieri PM , Protopopescu C , Laurent C , Spire B ,   Stratall ANRS 12110/ESTHER Study Group
Published: February 2015

Objectives

The World Health Organization (WHO) recommends task‐shifting HIV care to nurses in low‐resource settings with limited numbers of physicians. However, the effect of such task‐shifting on the health‐related quality of life (HRQL) of people living with HIV (PLHIV) has seldom been evaluated. We aimed to investigate the effect of task‐shifting HIV care to nurses on HRQL outcomes in PLHIV initiating antiretroviral therapy (ART) in rural district hospitals in Cameroon.

Methods

Outcomes in PLHIV were longitudinally collected in the 2006−2010 Stratall trial. PLHIV were followed up for 24 months by nurses and/or physicians. Six HRQL dimensions were assessed during face‐to‐face interviews using the WHO Quality of Life (WHOQOL)‐HIV BREF scale: physical health; psychological health; independence level; social relationships; environment; and spirituality/religion/personal beliefs. The degree of task‐shifting was estimated using a consultant ratio (i.e. the ratio of nurse‐led to physician‐led visits). The effect of task‐shifting and other potential correlates on HRQL dimensions was explored using a Heckman two‐stage approach based on linear mixed models to adjust for the potential bias caused by missing data in the outcomes.

Results

Of 1424 visits in 440 PLHIV (70.5% female; median age 36 years; median CD4 count 188 cells/μL at enrolment), 423 (29.7%) were task‐shifted to nurses. After multiple adjustment, task‐shifting was associated with higher HRQL level for four dimensions: physical health [coefficient 0.7; 95% confidence interval (CI) 0.1–1.2; P = 0.01], psychological health (coefficient 0.5; 95% CI 0.0–1.0; P = 0.05), independence level (coefficient 0.6; 95% CI 0.1–1.1; P = 0.01) and environment (coefficient 0.6; 95% CI 0.1–1.0; P = 0.02).

Conclusions

Task‐shifting HIV care to nurses benefits the HRQL of PLHIV. Together with the previously demonstrated comparable clinical effectiveness of physician‐based and nurse‐based models of HIV care, our results support the WHO recommendation for task‐shifting.