bluuebunny/crossref_metadata_2025 huggingface dataset:
Seasonal patterns of shell flux, δ18O and δ13C of small and large N. pachyderma (s) and G. bulloides in the subpolar North Atlantic
Authors: Jonkers Lukas , van Heuven Steven , Zahn Rainer , Peeters Frank J.C.
Published: February 2013

Past water column stratification can be assessed through comparison of the δ18O of different planktonic foraminiferal species. The underlying assumption is that different species form their shells simultaneously, but at different depths in the water column. We evaluate this assumption using a sediment trap time‐series of Neogloboquadrina pachyderma (s) and Globigerina bulloides from the NW North Atlantic. We determined fluxes, δ18O and δ13C of shells from two size fractions to assess size‐related effects on shell chemistry and to better constrain the underlying causes of isotopic differences between foraminifera in deep‐sea sediments. Our data indicate that in the subpolar North Atlantic differences in the seasonality of the shell flux, and not in depth habitat or test size, determine the interspecies Δδ18O. N. pachyderma (s) preferentially forms from early spring to late summer, whereas the flux of G. bulloides peaks later in the season and is sustained until autumn. Likewise, seasonality influences large and small specimens differently, with large shells settling earlier in the season. The similarity of the seasonal δ18O patterns between the two species indicates that they calcify in an overlapping depth zone close to the surface. However, their δ13C patterns are markedly different (>1‰). Both species have a seasonally variable offset from δ13CDIC that appears to be governed primarily by temperature, with larger offsets associated with higher temperatures. The variable offset from δ13CDIC implies that seasonality of the flux affects the fossil δ13C signal, which has implications for reconstruction of the past oceanic carbon cycle.
USING SELF‐MANAGEMENT INTERVENTIONS TO ADDRESS GENERAL EDUCATION BEHAVIORAL NEEDS: ASSESSMENT OF EFFECTIVENESS AND FEASIBILITY
Authors: Briesch Amy M. , Daniels Brian
Published: February 2013

A comprehensive self‐management intervention was utilized to increase the on‐task behavior of three African American students within an urban middle‐school setting. The intervention was designed to necessitate minimal management on the part of the general education classroom teacher by utilizing an electronic prompting device, as well as a centralized intervention coordinator for the management of training, implementation, and progress monitoring. Results suggested that implementation of the intervention resulted in improvement in on‐task behavior across all three students; however, problems with inconsistent implementation necessitated that modifications be made to the intervention procedures. Implications for the design and implementation of self‐management interventions within general education secondary‐level settings are discussed.
Molecular imprinted polymer films on RFID tags: a first step towards disposable packaging sensors
Authors: Croux Dieter , Vangerven Tim , Broeders Jeroen , Boutsen Jan , Peeters Marloes , Duchateau Stijn , Cleij Thomas , Deferme Wim , Wagner Patrick , Thoelen Ronald , De Ceuninck Ward
Published: February 2013

Molecular imprinted polymer (MIP) sensors offer a high potential in the development of cheap small‐scale disposable biomimetic sensors. Molecular imprinting leads to the formation of inert polymer particles with nanocavities, which can exhibit similar selectivity and specificity to target molecules as antibodies or enzymes. These sensors open up many possible applications in the field of mass‐market consumer products such as food packaging sensors. One such application is the detection of histamine in spoiled fish, which causes scombroid poisoning, a common seafood poisoning.

This contribution provides one possible solution for easing the use of these sensors in field applications. A screen‐printed short‐range wireless MIP‐based biosensor based upon passive radio frequency identification (RFID) tags was developed as a proof of principle. Histamine molecules binding to an MIP recognition layer induce a dielectric change in the sensor capacitance, resulting in a resonance frequency shift that is transmitted by inductive coupling. This wireless sensor is capable of detecting histamine concentrations as low as 50 nM at a range of a few centimeters.
Oxidation behavior and thermal stability of a NiAl–V eutectic alloy
Authors: Milenkovic Srdjan , Caram Rubens
Published: February 2013

Oxidation behavior and thermal stability of a NiAl–V alloy with eutectic composition processed by directional solidification technique has been investigated. The surface analysis at the elevated temperature indicated that the investigated microstructures are stable at the isothermal conditions and an inert atmosphere. The oxidation testing in the synthetic air showed that the temperature of 400 °C is critical. In addition, the oxidation of the NiAl–V eutectic alloy is characterized by: (a) alteration of composition immediately below the surface substrate/oxide; (b) formation of the oxide layer rich in V, adherent to the substrate; and (c) formation of external oxide layer that presents oxide mixture formed by vanadium, nickel, and aluminum.

Microstructure of the substrate/oxide interface of NiAl–V alloy oxidized at 900 °C for 24 h.
Phase development and electrical properties of Pb(Mg1/3Nb2/3)O3‐PbTiO3 ceramics prepared by partial oxalate route
Authors: Qian Kun , Fang Bijun , Du Qingbo , Ding Jianning , Zhao Xiangyong , Luo Haosu
Published: February 2013

(1 − x)Pb(Mg1/3Nb2/3)O3‐xPbTiO3 (PMN‐PT, x = 0.2–0.4) ferroelectric (FE) ceramics were prepared by the partial oxalate route. The synthesized PMN‐PT ceramics exhibit high density and densified microstructure although slight content of pyrochlore phase impurity exists. With the increase of PbTiO3 (PT) content, the phase structure of the PMN‐PT ceramics changes gradually from rhombohedral perovskite structure, across the morphotropic phase boundary (MPB) composition and to tetragonal perovskite structure. The FE structural phase transition of PMN‐PT changes gradually from the diffused ferroelectric phase transition (FPT) of typical relaxor FEs to nearly first‐order FPT of normal FEs, confirmed by dielectric and FE properties measurements. The PMN‐PT ceramics exhibit excellent dielectric and piezoelectric properties, and fully developed and saturated P–E hysteresis loops, in which the MPB effects are clearly shown by these electrical properties. The MPB composition of the PMN‐PT system is determined locating at x = 0.31–0.33 by XRD measurement and electrical properties measurements.
Economic Design of the Variable Parameters Control Chart with a Corrected A&L Switching Rule
Authors: Guo Zhi‐Fang , Cheng Long‐Sheng , Lu Zu‐Di
Published: February 2013

The variable parameters (VP) control chart is more efficient than the fixed parameters control chart. However, an obvious shortcoming of the VP control chart is its excessive number of switches among different design parameters, which significantly increases the complexity of operations for administer and the costs of maintaining the control chart. Amin and Letsinger (1991) proposed a switching rule, denoted by A&L switching rule, to reduce the number of switches. In this paper, we investigated the economic design of the VP control chart by using the corrected A&L switching rule scheme, which makes some corrections to the existing study of the A&L switching rule scheme. A three‐state Markov model is proposed to derive the performance measures of the suggested control chart. An expected cost model for the process is established with the cost function derived. The genetic algorithm is then employed to search for the solution for the economic design of the proposed control chart. The results obtained show that the developed model can significantly reduce the average number of the parameter's switches and save the expected cost in comparison with the conventional VP control scheme in detecting small and moderate mean shifts. A sensitivity analysis is also carried out to examine the effects of cost and model parameters on the solution of the economic design for the proposed control chart. The analysis demonstrates the expected cost per time unit is positively affected by the cost associated with a false signal, the average cost of repairs when a true signal is identified, the sampling cost and the cost associated with a switch, and is negatively affected by the cost associated with running the process in‐control per hour. Copyright © 2013 John Wiley & Sons, Ltd.
Importance of Pd and Pt excited states in N2O capture and activation: A comparative study with Rh and Au atoms
Authors: Poulain Enrique , Rubio‐Ponce Alberto , Uc Victor Hugo , Bertin Virineya , Olvera‐Neria Oscar
Published: February 2013

Nitrous oxide (N2O) is an intermediate compound formed during catalysis occurring in automobile exhaust pipes. In this work, the N2O capture and activation by Pt and Pd atoms in the ground and excited states of many multiplicities are studied. Pt and Pd + N2O reactions are studied at multireference second‐order perturbation level of theory using Cs symmetry. The PtN2O (1A′, 5A′, and 5A″) species are spontaneously created from excited states. Only the 5A′ and 5A″ states exhibit N2O activation reaction paths when N2O approaches Pt end‐on by the N or O atoms side or side‐on yielding NO or N2 as products, respectively. Pt+ cations ground and excited states, capture N2O, although only Pt+ (6A′ and 6A″) states show N2O activation yielding O and N2 as products. In the Pd atom case, PdN2O (1A′ and 5A″) species are also spontaneously created from excited states. The 5A″ state exhibits N2O activation yielding N2 + O as products. Pd+ cations in both ground and excited states capture N2O; however, only the [PdN2O]+ (4A′, 4A″, 6A′, and 6A″) states in side‐on approaches and (6A′) in end‐on approach activate the N2O and yield the N2 bounded to the metal and O as product. The results obtained in this work are discussed and compared with previous calculations of Rh and Au atoms. The reaction paths show a metal–gas dative covalent bonding character. Löwdin charge population analyses for Pt and Pd active states show a binding done through charge donation and retrodonation between the metals and N2O. © 2013 Wiley Periodicals, Inc.
Assessing the performance of density functional theory for the dynamic polarizabilities of amino acids: Treatment of correlation and role of exact exchange
Authors: Alipour Mojtaba , Mohajeri Afshan
Published: February 2013

The theoretical determination of electric response properties of the biological systems is a field where the application of density functional theory (DFT) appears to be quite promising. In this work, the performance of 41 density functional methods is evaluated in predicting dynamic polarizabilities of an experimental benchmark set of 20 proteinogenic amino acids. The behavior of a large number of density functionals, including various types of the local spin density approximation (LSDA), generalized gradient approximation (GGA), meta‐GGA (m‐GGA), hybrid‐GGA (h‐GGA), hybrid meta‐GGA (hm‐GGA), and range‐separated hybrid‐GGA (rsh‐GGA), has been assessed for the purpose. Analyzing the results of our DFT benchmarking, we found that these computationally economical methods show very diverse predictive capability and a careful selection of DFT functionals is very important in the polarizability calculations. Considering the role of exchange, correlation, dispersion and long‐range corrections, it turned out that in the LSDA class, SVWN3 gives better results than SPL and SVWN5 toward the reference values. Of the GGA methods, OPBE outperforms all other functionals. The M06‐L is the best method of m‐GGA class. The B3LYP and TPSSh are the best functionals of h‐GGA and hm‐GGA lineages, respectively. Finally, CAM‐B3LYP is the best method of rsh‐GGA functionals that predicts the most accurate polarizability for amino acids by a large margin with respect to others. Overall, the best performing functionals turn out to be hm‐GGAs TPSSh, TPSS1KCIS, M05, tau‐HCTHhyb, and h‐GGA B3LYP. Hopefully, the results of this investigation might provide the useful guidance to propose a new exchange‐correlation functional for calculating the optical properties of biomolecular materials. © 2013 Wiley Periodicals, Inc.
Argument on biometrics identity‐based encryption schemes
Authors: Tan Syh‐Yuan , Jin Zhe , Teoh Andrew Beng Jin
Published: February 2013

Recently, a few biometric identity‐based encryption (BIO‐IBE) schemes have been proposed. BIO‐IBE leverages both fuzzy extractor and Lagrange polynomial to extract biometric feature as a user public key and as a preventive measure of collusion attack, respectively. In this paper, we reveal that BIO‐IBE is not realistic whereby a query of fresh biometrics is needed for each encryption process. Moreover, the use of both fuzzy extractor and Lagrange polynomial in BIO‐IBE simultaneously is a redundancy; it confers no advantage, but simply computational overhead. Therefore, we amend the progression of the BIO‐IBE scheme by eliminating either Lagrange polynomial or fuzzy extractor to alleviate computational complexity. Subsequently, we demonstrate that the amendment does not compromise the security of the BIO‐IBE scheme. Such amendments can be applied to other BIO‐IBE schemes as well. Copyright © 2013 John Wiley & Sons, Ltd.
Quantification of AES depth profiling data of polycrystalline Al films with Gaussian and non‐Gaussian surface height distributions
Authors: Jian W. , Liu Y. , Wang X. Y. , Rao S. P. , Hofmann S. , Wang J. Y.
Published: February 2013

Sputtering‐induced roughness is the main distortional factor on the depth resolution of measured depth profiles, in particular, for sputtering of polycrystalline metals. Frequently, the surface height distribution of the sputtering‐induced roughness exhibits an asymmetrical feature. In such a case, a non‐Gaussian height distribution function (HDF) has to be applied for the quantification of a measured depth profile. By replacing the usually applied Gaussian HDF with that of an asymmetrical triangle in the Mixing‐Roughness‐Information depth model, measured Auger electron spectroscopy depth profiling data of the interface of polycrystalline Al films on Si are perfectly fitted. The asymmetric triangle height distributions obtained from the best fit are a reasonable approximation of the height distributions measured by atomic force microscopy. Copyright © 2013 John Wiley & Sons, Ltd.
Is levator avulsion a predictor of cystocele recurrence following anterior vaginal mesh placement?
Authors: Wong V. , Shek K. , Rane A. , Goh J. , Krause H. , Dietz H. P.
Published: February 2013

Objective

Levator avulsion has been shown to be a predictor of cystocele recurrence following anterior colporrhaphy. The aim of this study was to determine if levator avulsion is a risk factor for prolapse recurrence following anterior colporrhaphy with mesh.

Methods

This was a retrospective analysis of data obtained from three surgical audits for subjective and objective outcomes following anterior colporrhaphy with mesh. Recurrence was defined as cystocele ≥ Stage 2 on the prolapse quantification system of the International Continence Society; symptoms of vaginal lump/bulge; or cystocele on ultrasound, defined as maximum bladder descent to ≥ 10 mm below the symphysis pubis. Levator avulsion was diagnosed using tomographic ultrasound imaging.

Results

Two hundred and nine patients were followed up at a mean of 2.2 years (range, 3 months to 5.6 years) after anterior vaginal mesh placement. 24% (51/209) had recurrent prolapse symptoms, 33% (68/209) clinical cystocele recurrence ≥ Stage 2, and 26% (54/209) a recurrent cystocele on ultrasound. Twenty‐eight out of 80 (35%) women with levator avulsion had significant sonographic cystocele recurrence (odds ratio (OR), 2.24 (95% confidence interval (CI), 1.13–4.43)). This finding was confirmed after adjusting for potential predictors of prolapse recurrence on multivariate logistic regression (OR, 2.13 (95% CI, 1.04–4.39); P = 0.04).

Conclusion

Levator avulsion doubles the risk of cystocele recurrence after anterior colporrhaphy with transobturator mesh. Copyright © 2013 ISUOG. Published by John Wiley & Sons Ltd.
Characterization of a Namban folding screen from the Edo period by means of EDXRF, SEM‐EDS and Raman spectroscopy
Authors: Pessanha S. , LeGac A. , Madeira T. I. , Guilherme A. , Manso M. , Carvalho M. L.
Published: February 2013

In this work, a multianalytical approach is employed to characterize the materials used in a Namban folding screen that depicts the arrival of the Portuguese to the port of Nagasaki. Portuguese sailors reached Japan in 1543 and initiated what was to be known as the Namban trade. This interaction between Portuguese and Japanese was meticulously recorded by artists in the form of valuable and rare folding screens.

The present screen, attributed to the Edo period (~1603–1868), is what we could consider a second‐generation screen, a copy of scenes and characters that appear in screens from the Momoyama period (~1573–1603) but in increased scale and minor detail. The materials used in the screen were identified by means of in situ energy dispersive X‐ray fluorescence. Complementary results were obtained by Raman and scanning electron microscopy coupled to energy dispersive spectrometry analysis of microsamples taken from the screen.

The palette used in this artwork resorts to gold, malachite, azurite, vermillion, red lead, white oyster shell, and carbon black. Differences were found, when compared with previously studied screens, i.e. the use of mixtures of pigments, namely vermillion with red lead in an orange shade of red and also the mixture of vermillion and carbon black to obtain a brown color. Special emphasis was given to the characterization of the golden areas and study of techniques of gold application. Copyright © 2013 John Wiley & Sons, Ltd.
Decentralization andhukoureforms in China
Authors: Wu Ling
Published: February 2013

China is undergoing a process of decentralization that has been highly valued for its economic growth. However, this paper aims to explore how this process has affected the equality of social provision for rural–urban migrants in China by taking hukou system reform as a case study. It is argued here that the traditional assumption that decentralization promotes social welfare by bringing the government closer to the people is not necessarily true, or at least not uniformly so in certain institutional settings. Decentralization policies in contemporary China indeed make local governments more powerful and responsible for social welfare provision to their local citizens, but have also undermined the incentives for local governments to cover the welfare costs for migrant workers. To this extent, decentralization has played a negative role in integrating the large number of migrant workers into local cities and promoting equity within social welfare delivery at a national level in China.
Diosmin protects against trichloroethylene-induced renal injury in Wistar rats: plausible role of p53, Bax and caspases
Authors: Rehman Muneeb U. , Tahir Mir , Quaiyoom Khan Abdul , Khan Rehan , Lateef Abdul , Hamiza Oday O. , Ali Farrah , Sultana Sarwat
Published: February 2013

Diosmin (DM) is a naturally occurring flavone and has been found to possess numerous therapeutic properties. In this study, we used DM as a protective agent against the nephrotoxic effects of the environmental toxicant trichloroethylene (TCE). Male Wistar rats were divided into five groups (I–V,n6). Groups II, III and IV received an oral administration of TCE at a dose of 1000 mg/kg body weight for twenty consecutive days. The animals in groups II and III received an oral treatment of DM at doses of 20 and 40 mg/kg body weight, respectively, for twenty consecutive days, while groups I and V were given maize oil (5 ml/kg body weight and DM 40 mg/kg body weight, respectively) for 20 d. The protective effects of DM on TCE-induced oxidative stress and caspase-dependent apoptosis were investigated by assaying oxidative stress biomarkers, lipid peroxidation (LPO), serum toxicity markers, alkaline unwinding assay, caspase-3, -7 and -9, Bax and p53 expression. Oral administration of TCE in rats enhanced renal LPO, depleted glutathione content and antioxidant enzymes, induced DNA strand breaks (P< 0·001), modulated the expression of Bax and p53 protein and induced the expression of caspase-3, -7 and -9. Co-treatment with DM prevented oxidative stress by restoring the levels of antioxidant enzymes; furthermore, a significant dose-dependent decrease in DNA disintegration and kidney toxicity markers such as blood urea N, creatinine, lactate dehydrogenase and kidney injury molecule-1 was observed. DM also effectively decreased the TCE-induced up-regulation of Bax and p53. Data from the present study establish the protective role of DM against TCE-induced renal damage.
Interactions between Trichinella spiralis infection and induced colitis in mice
Authors: Ashour D.S. , Othman A.A. , Shareef M.M. , Gaballah H.H. , Mayah W.W.
Published: February 2013

Inflammatory bowel disease (IBD) is a chronic relapsing inflammation afflicting any part of the bowel wall as a result of a deregulated and inappropriate immune response. In recent years, experimental and clinical evidence has demonstrated that infection with parasitic worms could protect hosts from IBD. The aims of this study were to determine if the underlying mechanism of the host immune regulation inherent to Trichinella spiralis infection involves Foxp3-expressing regulatory T cells, and to gain insight about time-related interactions between intestinal nematode infection and induced colitis using an experimental model for ulcerative colitis. Mice were experimentally subjected to acetic acid-induced colitis, which was either preceded or followed by T. spiralis infection. Assessment of colitis was done by histopathological examination of the colon and determination of pentraxin 3 levels. Immunohistochemistry was done for demonstration of Foxp3-expressing regulatory T cells in colonic tissues. It was evident that T. spiralis infection ameliorated the severe inflammation induced by acetic acid, evidenced by amelioration of histopathological changes and diminution of pentraxin 3 levels. The amelioration was more pronounced when T. spiralis infection preceded the induction of colitis. Regarding the immunohistochemical staining of regulatory T cells, T. spiralis infection induced recruitment of Foxp3-expressing regulatory T cells to areas of inflammation. In conclusion, T. spiralis regulatory mechanism can improve inflammation of the colon through the ‘inflammatory–regulatory’ axis. Finally, it would be of great importance to apply these results to the development of new therapeutic approaches for the treatment of ulcerative colitis.
Negative pion stopping in ultra dense and hot DT targets of ICF fast ignition concern
Authors: DEUTSCH CLAUDE , FROMY PATRICE
Published: February 2013

In order to implement a Scenario of π− catalysis of Deuterium–Tritium (DT) thermonuclear reactions in a dense and hot precompressed target plasma envisioned in the Intertial Confinement Fusion (ICF) fast ignition approach, we pay detailed attention to the stopping of negative pions arising from electro-disintregration of target D and T nuclei by ultra-relativistic e-beams. Emphasis is put on a mostly non-relativistic pion velocity regime (E ≤ 10 MeV).
By-catch frequency and size differentiation in loggerhead turtles as a function of surface longline gear type in the western Mediterranean Sea
Authors: Báez José Carlos , Macías David , Camiñas Juan Antonio , Ortiz de Urbina José María , García-Barcelona Salvador , Bellido Juan Jesús , Real Raimundo
Published: February 2013

Fisheries by-catch is considered to be a major threat to loggerhead turtles in the Mediterranean Sea. Technical differences in both gear configurations (e.g. hook and bait type) and fisheries operations carried out by the Spanish Mediterranean surface longline fleet could have an effect on by-catch rates and size selectivity. The aim of the present study was to test the differences in by-catch per unit effort and body size of loggerhead sea turtles caught using different gear types in the Mediterranean surface longline fishery. Our results suggest that differences in the gear type used have an effect on catch rates and size selectivity. Thus, surface longliners targeting albacore (LLALB) using smaller hooks tend to capture smaller loggerheads but have the highest by-catch per unit of effort (BPUE), whereas other longlines, such as surface longliners targeting bluefin tuna (LLJAP) and traditional surface longliners targeting swordfish (LLHB), using larger hooks tend to select the larger animals; moreover, LLHB had the lowest BPUE. Disproportionate rates of fisheries-induced mortality on certain size/age-classes can differentially affect sea turtle populations, as each sea turtle age-class contributes differently to current and future reproduction. Thus, fisheries management should not only be focusing on preserving the large juvenile and mature turtles, but also on reducing the total by-catch. Thus, we recommend encouraging the use of LLHB versus other surface gears. We suggest that it is very important to take into account the gear type (and its particular catch rates) when making inferences about the impact of longline fisheries on sea turtle populations.
Growth rates are related to production efficiencies in juveniles of the sea urchinLytechinus variegatus
Authors: Heflin L.E. , Gibbs V.K. , Jones W.T. , Makowsky R. , Lawrence A.L. , Watts S.A.
Published: February 2013

Growth rates of newly-metamorphosed urchins from a single spawning event (three males and three females) were highly variable, despite being held en masse under identical environmental and nutritional conditions. As individuals reached ~5 mm diameter (0.07–0.10 g wet weight), they were placed in growth trials (23 dietary treatments containing various nutrient profiles). Elapsed time from the first individual entering the growth trials to the last individual entering was 121 days (N = 170 individuals). During the five-week growth trials, urchins were held individually and proffered a limiting ration to evaluate growth rate and production efficiency. Growth rates among individuals within each dietary treatment remained highly variable. Across all dietary treatments, individuals with an initially high growth rate (entering the study first) continued to grow at a faster rate than those with an initially low growth rate (entering the study at a later date), regardless of feed intake. Wet weight gain (ranging from 0.13–3.19 g,P<0.0001, R2 = 0.5801) and dry matter production efficiency (ranging from 25.2–180.5%,P = 0.0003, R2 = 0.6162) were negatively correlated with stocking date, regardless of dietary treatment. Although canalization of growth rate during en masse early post-metamorphic growth is possible, we hypothesize that intrinsic differences in growth rates are, in part, the result of differences (possibly genetic) in production efficiencies of individualLytechinus variegatus. That is, some sea urchins are more efficient in converting feed to biomass. We further hypothesize that this variation may have evolved as an adaptive response to selective pressure related to food availability.
How good is research really?
Authors: Bornmann Lutz , Marx Werner
Published: February 2013

Bibliometrics increasingly determine the allocation of jobs and funding in science. Bibliometricians must therefore develop and adopt reliable measures of quality that truly reflect a scientist's contribution to his or her field.
Nucleoprotein of influenza A virus is a major target of immunodominant CD8+ T‐cell responses
Authors: Grant Emma , Wu Chao , Chan Kok‐Fei , Eckle Sidonia , Bharadwaj Mandvi , Zou Quan Ming , Kedzierska Katherine , Chen Weisan
Published: February 2013

Influenza A virus causes annual epidemics and sporadic pandemics, resulting in significant morbidity and mortality worldwide. Vaccines are currently available; however, they induce a non‐strain‐cross protective humoral immune response directed against the rapidly mutating surface glycoproteins, and thus need to be updated annually. As T cells are directed against more conserved internal influenza proteins, a T‐cell‐based vaccine has the potential to induce long‐lasting and cross‐strain protective CD8+ T‐cell immunity, and in that way minimize the severity of influenza infection. However, to rationally design such vaccines, we need to identify immunogenic T‐cell regions within the most antigenic viral proteins. In this study, we have used a systematic approach to identify immunodominant peptides in HLA‐A2‐negative donors. A broad range of CD8+ T‐cell responses were observed and 6/7 donors had an immunodominant response against the relatively conserved internal nucleoprotein (NP). Dissecting the minimal epitope regions within the immunogenic NP led to the identification of six novel immunodominant epitopes, which include a 12‐mer and an 8‐mer peptides. The majority of immunodominant epitopes was clustered within the carboxyl terminal 2/3 of the NP protein and were highly conserved. We also subjected NP to three common computer algorithms for epitope prediction and found that most of the novel epitopes would not have been predicted. Our study emphasizes the importance of using a systematic approach to identify immunodominant CD8+ T‐cell responses and suggests that the epitope‐rich regions within NP present a promising target for the T‐cell‐mediated multi‐strain influenza vaccine.
Theory of nanoparticles doped in ferroelectric liquid crystals
Authors: Lahiri T. , Pal Majumder T. , Ghosh N. K.
Published: February 2013

We developed a theory for the statistical mechanics of nanoparticles doped in ferroelectric liquid crystals (FLC). The presence of nanoparticles in FLC medium creates strong local fields that produce large alignment effects over the distribution of the nanosuspensions. Considering these local field effects, we presented a modified Landau free energy to calculate the electro-optic properties of the system. Then, we investigated the response of the nanoparticles doped FLC to an applied electric field. The variations in the polarization and the tilt angle show marked differences with the pure FLC medium. The rotational viscosity of the system is also calculated with its possible variation in temperature and applied field. Then, we conjectured on the possibility of shift in transition temperature, which is supposed to be induced by an electrostatic interaction between the nanoparticles and the liquid crystal molecules. Finally, strong experimental evidence is presented in favor of our results emerged from this theoretical model.
Conductivity enhancement and resistance changes in polymer films filled with reduced graphene oxide
Authors: Okhay O. , Krishna R. , Salimian M. , Titus E. , Gracio J. , Guerra L. M. , Ventura J.
Published: February 2013

The electrical properties of polymer composites based on polycarbonate (PC) and panipol CXM (CX), filled with reduced graphene oxide (rGO), were investigated. The composite preparation conditions allowed good dispersion of rGO in the polymer matrix. We show here that when used as a nanofiller in polymers, rGO offers an appreciable improvement of the electrical current in 3 orders of magnitude (from 10−10 A to 10−7 A at 10 V), as observed in current-voltage (I-V) data for both PC and CX polymers with rGO. The suggested mechanism for the observed switching effects is the migration of oxygen groups aided by both the electrical field and Joule heating. Moreover, some reset- and set- like changes similar to resistive switching were observed in the I-V data of PC and CX-based films upon the addition of rGO. Clockwise (resembling a memristive system type II) and counter-clockwise (resembling a memristive system type I) directions were detected in the I-V data of the analyzed films. According to the obtained results, rGO can be a good filler for PC and CX polymer-based films for application in electronic and photonic areas, due to the significant improvement of the electrical conductivity of these polymers.
Thermal properties of carbon nanowall layers measured by a pulsed photothermal technique
Authors: Achour A. , Belkerk B. E. , Ait Aissa K. , Vizireanu S. , Gautron E. , Carette M. , Jouan P.-Y. , Dinescu G. , Brizoual L. Le , Scudeller Y. , Djouadi M.-A.
Published: February 2013

We report the thermal properties of carbon nanowall layers produced by expanding beam radio-frequency plasma. The thermal properties of carbon nanowalls, grown at 600 °C on aluminium nitride thin-film sputtered on fused silica, were measured with a pulsed photo-thermal technique. The apparent thermal conductivity of the carbon at room temperature was found to increase from 20 to 80 Wm−1 K−1 while the thickness varied from 700 to 4300 nm, respectively. The intrinsic thermal conductivity of the carbon nanowalls attained 300 Wm−1 K−1 while the boundary thermal resistance with the aluminium nitride was 3.6 × 10−8 Km2 W−1. These results identify carbon nanowalls as promising material for thermal management applications.
The effect of particle strength on the ballistic resistance of shear thickening fluids
Authors: Petel Oren E. , Ouellet Simon , Loiseau Jason , Marr Bradley J. , Frost David L. , Higgins Andrew J.
Published: February 2013

The response of shear thickening fluids (STFs) under ballistic impact has received considerable attention due to its field-responsive nature. While efforts have primarily focused on traditional ballistic fabrics impregnated with these fluids, the response of pure STFs to penetration has received limited attention. In the present study, the ballistic response of particle-based STFs is investigated and the effects of fluid density and particle strength on ballistic performance are isolated. It is shown that the loss of ballistic resistance in the STFs at higher impact velocities is governed by the material strength of the particles in suspension. The results illustrate the range of velocities over which these STFs may provide effective armor solutions.
Communication: Simulated tempering with fast on-the-fly weight determination
Authors: Nguyen Phuong H. , Okamoto Yuko , Derreumaux Philippe
Published: February 2013

We propose an efficient method to enhance sampling in computer simulations by combining the simulated tempering algorithm with a fast on-the-fly weight determination scheme. The weights are self-updated via a trapezoid rule during the simulated tempering simulation. With our proposed scheme, simulated tempering requires neither prior trial simulations nor complicated update schemes. The advantage of our method over replica exchange molecular dynamics has been demonstrated with the study of the folding of the 20-residue alanine peptide and the aggregation of a trimer formed by the Alzheimer's peptide fragment Aβ16−22.
Negative dielectric constant manifested by static electricity
Authors: Yan Han , Zhao Cindy , Wang Kevin , Deng Lucy , Ma Matthew , Xu Gu
Published: February 2013

Negative dielectric constant has long been pursued for a possible revolution in electronics and photonics. It is usually found in systems containing free electrons under high frequency oscillating field, but not involving static charges or insulating materials. Here, we report the observation of the phenomenon in an insulating polymer containing static electricity, which lasts for several weeks, where negative capacitance persists from <1 Hz up to MHz frequency, also presenting an unusual spiral curve in impedance spectrum, producing inductors without bulky magnetic coils.
Resonance ultrasonic thermography: Highly efficient contact and air-coupled remote modes
Authors: Solodov Igor , Busse Gerd
Published: February 2013

A frequency match between the driving ultrasonic wave and characteristic frequency of a defect provides an efficient energy pumping from the wave directly into the defect. The application of the concept of local defect resonance is shown to enhance substantially the efficiency of vibro-thermal conversion in ultrasonic thermography (ULT). Therefore, the resonance modes of ultrasonic thermography require much lower acoustic power to activate defects that makes it possible to avoid high-power ultrasonic instrumentation and proceed to a remote ultrasonic thermography version by using air-coupled ultrasonic excitation.
Harnessing second-order optical nonlinearities at interfaces in multilayer silicon-oxy-nitride waveguides
Authors: Logan Dylan F. , Alamin Dow Ali B. , Stepanov Dmitri , Abolghasem Payam , Kherani Nazir P. , Helmy Amr S.
Published: February 2013

We demonstrate multi-layer silicon-oxy-nitride (SiON) waveguides as a platform for broadband tunable phase-matching of second-order nonlinear interactions arising at material interfaces. Second-harmonic generation (SHG) is measured with a 2 ps pulsed pump of 1515–1535 nm wavelength, where 6 nW power is generated by an average pump power of 30 mW in a 0.92 mm long device. The wavelength acceptance bandwidth of the SHG is as broad as 20 nm due to the low material dispersion of SiON waveguides. The waveguide structure provides a viable method for utilizing second order nonlinearity for light generation and manipulation in silicon photonic circuits.
Rapid hot-electron energy relaxation in lattice-matched InAlN/AlN/GaN heterostructures
Authors: Zhang J.-Z. , Dyson A. , Ridley B. K.
Published: February 2013

Hot-electron energy relaxation is theoretically studied for a typical lattice-matched InAlN/AlN/GaN heterostructure, including effects of non-equilibrium phonons and screening from the mobile electrons in the GaN channel. A dramatic fall of relaxation time occurs at low electron temperatures (<500 K) due to the exponentially increased phonon generation as well as fast decreased screening and hot-phonon effect. At high electron temperatures (>1500 K), on the other hand, the hot-phonon effect is very weak because of short optical phonon lifetimes (experimental value ∼0.1 ps), and the electron relaxation is dictated by the screened electron-phonon interactions which alone yield a nearly constant relaxation time ∼0.1 ps. With increasingly fast optical-phonon decay, therefore the high-temperature electron relaxation time decreases slowly with the electron temperature, with its limiting value set entirely by the screened electron-phonon interactions alone. The calculated dependence of the relaxation time on the electron temperature and the high-temperature relaxation times ∼0.1 ps are in good agreement with experimental results.
The application of fractal box dimensions in predicting the emission characteristics of colliding sawdust particles for sustainable sawmilling
Authors: Salau T. A. O. , Oke S. A.
Published: February 2013

The prediction of emission characteristics of sawdust particles immediately after the cutting operation from the interaction of band saw?s blade and plank is a growing research area. Still, a wide gap exists with respect to understanding the behaviour of sawdust particles as they collide with one another. Previous efforts have focused on non-collision states of sawdust particles. However, in real life, collision of particles must occur, with several particles colliding after the cutting operation. This paper establishes a new perspective of the fractal properties of sawdust particles in motion as a motivation to understanding how to control its toxicity of effects on sawmill workers and maintain sustainable sawmilling activities. In particular, the possibility of predicting the fractal dimension of the randomly moving sawdust particles in sawmills that is generated as fractal curves using the combination of probabilities and theoretical fractal dimensions is investigated for the first time. Cases
were established on the possible representations of the theory and practice. As an example, four cases were designed around varied number of fractal pattern combinations drawn out of five and fifty different probabilities combinations, ten different random number generating seed values and maximum of four fractal curves generation iterations as driven parameters. Preliminary study of the differences between theoretical fractal box dimension recorded a maximum absolute percentage error of 7.24% for fractal curve associated with fractal pattern five (i.e. Koch 5). In all the cases studied, average absolute percentage error decreases between 3.52 � 1.18 and 1.51 � 1.14 while the correlation coefficient (R2) decreases between 0.9315 and 0.7365 from case 1 to case 4, respectively. It is concluded that the model is a good predictor of sawdust particle emission at colliding states from cutting operation. This is reflected in the fact that the higher the number of fractal patterns (generators) in a study case, the smaller the correlation coefficient between average estimated fractal box dimension and predicted fractal dimension of the sawdust particles in motion in the sawmill.
Diverse and abundant antibiotic resistance genes in Chinese swine farms
Authors: Zhu Yong-Guan , Johnson Timothy A. , Su Jian-Qiang , Qiao Min , Guo Guang-Xia , Stedtfeld Robert D. , Hashsham Syed A. , Tiedje James M.
Published: February 2013

Antibiotic resistance genes (ARGs) are emerging contaminants posing a potential worldwide human health risk. Intensive animal husbandry is believed to be a major contributor to the increased environmental burden of ARGs. Despite the volume of antibiotics used in China, little information is available regarding the corresponding ARGs associated with animal farms. We assessed type and concentrations of ARGs at three stages of manure processing to land disposal at three large-scale (10,000 animals per year) commercial swine farms in China. In-feed or therapeutic antibiotics used on these farms include all major classes of antibiotics except vancomycins. High-capacity quantitative PCR arrays detected 149 unique resistance genes among all of the farm samples, the top 63 ARGs being enriched 192-fold (median) up to 28,000-fold (maximum) compared with their respective antibiotic-free manure or soil controls. Antibiotics and heavy metals used as feed supplements were elevated in the manures, suggesting the potential for coselection of resistance traits. The potential for horizontal transfer of ARGs because of transposon-specific ARGs is implicated by the enrichment of transposases—the top six alleles being enriched 189-fold (median) up to 90,000-fold in manure—as well as the high correlation (
r
2
= 0.96) between ARG and transposase abundance. In addition, abundance of ARGs correlated directly with antibiotic and metal concentrations, indicating their importance in selection of resistance genes. Diverse, abundant, and potentially mobile ARGs in farm samples suggest that unmonitored use of antibiotics and metals is causing the emergence and release of ARGs to the environment.
Mitosis–meiosis and sperm–oocyte fate decisions are separable regulatory events
Authors: Morgan Clinton T. , Noble Daniel , Kimble Judith
Published: February 2013

Germ cell fate decisions are poorly understood, despite their central role in reproduction. One fundamental question has been whether germ cells are regulated to enter the meiotic cell cycle (i.e., mitosis–meiosis decision) and to be sperm or oocyte (i.e., sperm–oocyte decision) through one or two cell fate choices. If a single decision is used, a male-specific or female-specific meiotic entry would lead necessarily toward spermatogenesis or oogenesis, respectively. If two distinct decisions are used, meiotic entry should be separable from specification as sperm or oocyte. Here, we investigate the relationship of these two decisions with tools uniquely available in the nematode
Caenorhabditis elegans
. Specifically, we used a temperature-sensitive Notch allele to drive germ-line stem cells into the meiotic cell cycle, followed by chemical inhibition of the Ras/ERK pathway to reprogram the sperm–oocyte decision. We found that germ cells already in meiotic prophase can nonetheless be sexually transformed from a spermatogenic to an oogenic fate. This finding cleanly uncouples the mitosis–meiosis decision from the sperm–oocyte decision. In addition, we show that chemical reprogramming occurs in a germ-line region where germ cells normally transition from the mitotic to the meiotic cell cycle and that it dramatically changes the abundance of key sperm–oocyte fate regulators in meiotic germ cells. We conclude that the
C
.
elegans
mitosis–meiosis and sperm–oocyte decisions are separable regulatory events and suggest that this fundamental conclusion will hold true for germ cells throughout the animal kingdom.
Rag GTPases mediate amino acid–dependent recruitment of TFEB and MITF to lysosomes
Authors: Martina Jose A. , Puertollano Rosa
Published: February 2013

The mTORC1 complex supports cell growth and proliferation in response to energy levels, growth factors, and nutrients. The Rag guanosine triphosphatases (GTPases) activate mTORC1 in response to amino acids by promoting its redistribution to lysosomes. In this paper, we identify a novel role for Rags in controlling activation of transcription factor EB (TFEB), a master regulator of autophagic and lysosomal gene expression. Interaction of TFEB with active Rag heterodimers promoted recruitment of TFEB to lysosomes, leading to mTORC1-dependent phosphorylation and inhibition of TFEB. The interaction of TFEB with Rags required the first 30 residues of TFEB and the switch regions of the Rags G domain. Depletion or inactivation of Rags prevented recruitment of TFEB to lysosomes, whereas expression of active Rags induced association of TFEB with lysosomal membranes. Finally, Rag GTPases bound and regulated activation of microphthalmia-associated transcription factor, suggesting a broader role for Rags in the control of gene expression. Our work provides new insight into the molecular mechanisms that link nutrient availability and TFEB localization and activation.
Cytotoxic T cells induce proliferation of chronic myeloid leukemia stem cells by secreting interferon-γ
Authors: Schürch Christian , Riether Carsten , Amrein Michael A. , Ochsenbein Adrian F.
Published: February 2013

Chronic myeloid leukemia (CML) is a clonal myeloproliferative neoplasia arising from the oncogenic break point cluster region/Abelson murine leukemia viral oncogene homolog 1 translocation in hematopoietic stem cells (HSCs), resulting in a leukemia stem cell (LSC). Curing CML depends on the eradication of LSCs. Unfortunately, LSCs are resistant to current treatment strategies. The host’s immune system is thought to contribute to disease control, and several immunotherapy strategies are under investigation. However, the interaction of the immune system with LSCs is poorly defined. In the present study, we use a murine CML model to show that LSCs express major histocompatibility complex (MHC) and co-stimulatory molecules and are recognized and killed by leukemia-specific CD8+ effector CTLs in vitro. In contrast, therapeutic infusions of effector CTLs into CML mice in vivo failed to eradicate LSCs but, paradoxically, increased LSC numbers. LSC proliferation and differentiation was induced by CTL-secreted IFN-γ. Effector CTLs were only able to eliminate LSCs in a situation with minimal leukemia load where CTL-secreted IFN-γ levels were low. In addition, IFN-γ increased proliferation and colony formation of CD34+ stem/progenitor cells from CML patients in vitro. Our study reveals a novel mechanism by which the immune system contributes to leukemia progression and may be important to improve T cell–based immunotherapy against leukemia.