bluuebunny/crossref_metadata_2025 huggingface dataset:
Transforming JAK1 mutations exhibit differential signalling, FERM domain requirements and growth responses to interferon-γ
Authors: Gordon Geoff M. , Lambert Que T. , Daniel Kenyon G. , Reuther Gary W.
Published: September 2010

Recent work has highlighted roles for JAK (Janus kinase) family members in haemopoietic diseases. Although sequencing efforts have uncovered transforming JAK1 mutations in acute leukaemia, they have also identified non-transforming JAK1 mutations. Thus with limited knowledge of the mechanisms of JAK1 activation by mutation, sequencing may not readily identify transforming mutations. Therefore we sought to further understand the repertoire of transforming mutations of JAK1. We identified seven randomly generated transforming JAK1 mutations, including V658L and a deletion of amino acids 629–630 in the pseudokinase domain, as well as L910P, F938S, P960S, K1026E and Y1035C within the kinase domain. These mutations led to differential signalling activation, but exhibited similar transforming abilities, in BaF3 cells. Interestingly, these properties did not always correlate with JAK1 activation-loop phosphorylation. We also identified a JAK1 mutant that did not require a functional FERM (4.1/ezrin/radixin/moesin) domain for transformation. Although we isolated a mutation of JAK1 at residue Val658, which is found mutated in acute leukaemia patients, most of the mutations we identified are within the kinase domain and have yet to be identified in patients. Interestingly, compared with cells expressing JAK1-V658F, cells expressing these mutants had higher STAT1 (signal transducer and activator of transcription 1) phosphorylation and were more sensitive to interferon-γ-mediated growth inhibition. The differential STAT1 activation and interferon-sensitivity of JAK1 mutants may contribute to the determination of which specific JAK1 mutations ultimately contribute to disease and thus are identified in patients. Our characterization of these novel mutations contributes to a better understanding of mutational activation of JAK1.
Effects of racecadotril and loperamide on bacterial proliferation and on the central nervous system of the newborn gnotobiotic piglet
Authors: Duval‐Iflah Y. , Berard H. , Baumer P. , Guillaume P. , Raibaud P. , Joulin Y. , Lecomte J.M.
Published: September 2010

Methods The effects of 4 days of oral administration of different doses of two drugs, an enkephalinase inhibitor (the antisecretory agent, racecadotril) and a μ‐receptor agonist (loperamide), on intestinal growth of a bacterial nonpathogenic strain (Escherichia coli E 404) and on the central nervous system (CNS) were compared in newborn gnotobiotic piglets.

Results The E. coli content of the proximal jejunum (segment S1) and the E. coli ratio of stomach:segment S1 were similar in the racecadotril (20 mg/kg b.d., n = 5) and control groups. In contrast, in the loperamide group (1 mg/kg b.d., n = 4), the E. coli content of segment S1 and the E. coli ratio stomach:S1 were both significantly higher than with racecadotril or control (P = 0.04 and 0.005, respectively, for E. coli content; P = 0.05 and 0.03, respectively, for stomach:S1). There were no clinical signs of neurotoxicity and no deaths with racecadotril given orally at a high dose of 130 mg/kg b.d. (n = 5) – nearly 60 times the paediatric dosage. In contrast, an equivalent high dose of loperamide (5 mg/kg b.d.) resulted in death in three out of four piglets.

Conclusions In contrast to loperamide, racecadotril did not induce bacterial overgrowth and did not produce central neurotoxicity.
White Blood Cell Transfusions for Control of Infections in Neutropenic Patients
Authors: Vallejos C. , McCredie K. B. , Bodey G. P. , Hester J. P. , Freireich E. J.
Published: September 2010

Four hundred and fifty‐four leukocyte transfusions from unrelated donors with chronic myelogenous leukemia were given to 128 patients during 179 febrile episodes with a median circulating granulocyte count prior to leukocyte transfusions of 80/cm. Forty‐nine per cent of the serious and life‐threatening infections responded to a combination of granulocyte transfusions and appropriate antibiotic therapy. Minor complications occurred in approximately 25 per cent of patients and more severe toxicity was seen in only 2 per cent. No deaths were attributed to leukocyte transfusions.
Management Policies for a Regional Blood Bank
Authors: Cohen M. A. , Pierskalla W. P.
Published: September 2010

This paper considers management strategies for the administration of a regional blood bank. The techniques of management science and mathematical inventory theory are applied to construct a model for the system, identify policy areas, and formulate management objectives. Two simulation models and data collected from both a regional and single hospital blood bank are used in the analysis. The results presented examine the interactions and savings associated with following optimal ordering, crossmatch, and issuing policies. Since each of these policies have an important effect on the number of shortages and outdates, they therefore influence optimal blood bank management. In addition, the question of centralized versus decentralized control is examined.
The Motivations of Blood Donors and Nondonors: A Community Survey
Authors: Oswalt R. M. , Hoff T. E.
Published: September 2010

Telephone interviews elicited information on motivational responses of blood donors and nondonors from a completely random sample of an entire community. Results indicated that more males than females are current donors and that 63 per cent of the males and 89 per cent of the females who have donated previously have become nondonors. Most donors express no fears before donating and state direct appeal, convenience, and peer pressure as the motivational aspects that caused them to donate in the first place, and altruism as the major reason for continuing to donate. The two largest categories mentioned by nondonors for inhibiting their donating were medical disqualification and fear.

When both donors and nondonors made suggestions for improving blood donor recruitment, they tended to mention publicity (including education), emergency appeal, and personal solicitation. The first two were not mentioned by actual donors as to what motivated them to give blood initially. Blood procurement agencies should, therefore, be aware of a distinction between actual motivating factors and those that are only hypothetical.
Effects of Donor Recruitment Methods on Population Responses
Authors: Ford G. T. , Wallace E. L.
Published: September 2010

It is important to know the preferences of blood donors and nondonors as to 1) the method of contact of the prospective donor by the recruiter, 2) the character of the relationship between the recruiter and the recruit, 3) the recruitment message used by the recruiter, and 4) the logistics of the collection. Interviews with almost 2,000 blood donors and nondonors in the Buffalo region were done to provide information on these preferences.

Results of the studies include evidence that face‐to‐face recruiting is over three times as effective as is recruiting by the telephone. The relationship between recruiter and recruit is important primarily to first‐time donors. The recruitment message should include all of the reasons for donating. Replacement donors are a good source of future volunteers, and the logistics of blood collection, particularly selection of donor sites and overall time required to donate, are crucial in determining donor responses.
Multiple Differences in Red Cell Antigens and Isoimmunization
Authors: Stern K.
Published: September 2010

Data available for 175 families with maternal isoimmunization to red blood cell antigens, exclusive of A, B, and Rh0, were analyzed for interaction of unrelated antigens. In 153 families the mother developed antibodies for single antigens, distributed among seven blood group systems; rare, high frequency antigens; and unclassified antigens. The immunizing fetal red blood cells were ABO‐incompatible with the mother in less than 5 per cent of instances, a finding attesting to the impact of ABO incompatibility on immunogenicity of most red blood cell antigens. No evidence was found for interference with immunization to one particular red blood cell antigen by simultaneous differences in unrelated antigens. Maternal immunization to more than one red blood cell antigen, encountered in 22 families, was associated in 13 instances with preceding blood transfusion to the mother and/or pregnancies in which fetal red blood cells contained only one of the immunizing antigens. In six of the remaining nine instances of multiple isoimmunization, Kidd antibodies were involved. Preceding immunization to a variety of red blood cell antigens was noted to interfere with immunization to potent immunogens: Rh0 (nine instances of complete, and one instance of partial, suppression), hr‘ (eight instances of suppression), and K (two instances of suppression). A mechanism, designated as “diversion of antigen,” was proposed in order to explain the phenomena observed in human isoimmunization as well as in animal models in which preceding immunization to one red blood cell antigen affects immune responses to red blood cells carrying the immunizing and additional antigens.
Evaluation of Platelet Cryopreservation Techniques by Isolated Kidney Perfusion
Authors: Raymond S. L. , Pert J. H. , Dodds W. J.
Published: September 2010

The isolated perfused rabbit kidney, a model system used previously to assess platelet function, was adapted for evaluation of human platelet cryopreservation techniques. A new, simple, efficient device for controlling cooling rates before, during, and after freezing was used. Platelet concentrates frozen with 5 per cent dimethyl sulfoxide (DMSO) under different conditions were the most effective of those tried in maintaining the hemostatic function and vascular integrity of perfused kidneys. Our studies indicate that the isolated, perfused rabbit kidney can be used to evaluate platelet cryopreservation techniques and is potentially adaptable for studies of organ cryopreservation.
A Computer‐Based Frozen Blood Inventory and Information System
Authors: Roberts S. C. , Ruess D. T. , Camp F. R.
Published: September 2010

A computer‐based, time‐sharing data processing system was developed to assist in maintaining information regarding units of red blood cells frozen for eventual transfusion. An automated system has been programmed to compile and retrieve data concerning stored units, prepare shipping documents as required, and maintain transfusion records in a retrievable manner for thawed or shipped units.

Requests for frozen red blood cells are processed through this system. Units are selected by the computer to meet requirements specified by the operator of a keyboard terminal. These requirements include method of cryopreservation, specific antigenic characteristics required, and the number of units requested. The computer prints out on the keyboard terminal the units meeting the requirements and the keyboard operator then indicates to the computer the name of the requesting facility, if these units are to be shipped. This input initiates a programmed routine that generates a shipping invoice and a new file for these units in a permanent transfusion record which can be accessed by either donor number or the frozen blood cell code.
The Development of a Recruiting‐Drawing‐Inventory Model for a Community Blood Bank System
Authors: Smackey B. M.
Published: September 2010

A community blood bank system is a multiorganizational program that is designed to supply the blood needs of a community. Participating in such a program are hospitals, a central blood bank, industrial donor groups, the American Red Cross, advisory committees, and the community at large. The underlying determinant of the community's success or failure with its blood program is the degree of cooperation among the various organizations. Intertwined with organizational considerations are the management problems associated with the operation of a responsive and efficient inventory control system. This paper reports on the development of a system for a community blood bank that is in its third year of operation. The system that has been developed can be operated manually by a part‐time clerk. Details of the model include an integration of the donor scheduling function and the inventory control function. Simulated testing of the model has been conducted and full‐scale implementation is awaiting the expansion of the known donor base.
Improved Granulocyte Collection from Normal Donors by Combination of Continuous‐Flow Centrifugation and Filtration Leukapheresis
Authors: Gmür J. P. , Deluigi J. , Straub P. W.
Published: September 2010

A total of 30 leukaphereses were performed with the Aminco Cellseparator on 27 healthy donors. Pre‐treatment by steroids and addition of fluid gelatin to the input line was performed in all runs. The combination of continuous flow centrifugation and filtration leukapheresis (CFC‐FL) in nine of the 30 runs resulted in a highly significant increase of the yield to a mean of 59.6 × 10s granulocytes as compared with a mean of 30.8 × 109 granulocytes obtained with conventional CFC. This significance is valid for the total yield of granulocytes, the yield per hour of run, or per liter of blood processed. No adverse reaction occurred.
Purification and Use of the C3d Subunit of C3
Authors: Moore J. A. , Michael J. M. , Chaplin H.
Published: September 2010

A method is described for the preparation of C3d from fresh‐frozen CPD plasma. A redissolved EDTA euglobulin precipitate formed from defibrinated plasma is chromatographed on DEAE cellulose. The C3‐rich peak is further chromatographed by stepwise elution from hydroxyl‐apatite. The highly purified C3 and C3b so obtained are then treated with commercial C3b inactivator. C‐200 sephadex filtration of this material produces a low molecular weight peak containing C3d in > 95 per cent purity. The purified C3d, which contains negligible carbohydrate, has a molecular weight of 28,000 (based on SDS polyacrylamide gel electrophoresis). When added at a final concentration of < 70 μg per ml, it completely inhibits the anti‐C3d hemagglutinin reactivity of a potent anti‐C3d antiglobulin serum but does not inhibit sera with reactivities against C3c, C4b, and CSb. Two of three rabbits hyper immunized with purified C3d produced antisera exhibiting only anti‐C3d precipitin activity. After absorption of heterologous antibodies, the antisera strongly agglutinated C3d‐coated RBC, failed to agglutinate RBC coated only with C4, and reacted weakly against strongly anti‐Rh‐coated RBC. The latter reactivity was readily absorbed by whole IgC. Preliminary studies with 125I‐Iabeled C3d indicate its potential value in assessing potency of anti‐C3d reagents.
Survival of Transfused Factor VIII in Hemophilic Patients Treated with Epsilon Aminocaproic Acid
Authors: Weiss A. E. , Webster W. P. , Strike L. E. , Brinkhous K. M.
Published: September 2010

The effect of EACA (epsilon aminocaproic acid) on the survival of factor VIII (F. VIII, antihemophilic factor, AHF) concentrates after infusion in hemophilic subjects was studied using two F. VIII preparations: an intermediate purity “cryoglobulin” and a high purity glycine‐precipitated concentrate. In vivo recoveries of F. VIII with both concentrates were found to be close to the values predicted on the basis of concentrate potencies assayed prior to infusion, but not if the labeled potency was used in the calculation. Control studies showed similar first and second phase half‐life times and half‐disappearance times when the two F. VIII preparations were infused, and both preparations were found to follow a biphasic disappearance curve. The biological half‐life (second phase rate of disappearance) was 12 to 13 hours. The administration of EACA in conjunction with the F. VIII concentrates did not prolong the half‐life times (first or second phase) or the half‐disappearance times.
Eluate Analysis of Anti‐Bga Associated Renal Allograft Rejection
Authors: Frist S. , Wenz B.
Published: September 2010

Renal allograft rejection, following development of a positive indirect antiglobulin reaction, occurred in a multiply transfused recipient. Panel techniques confirmed both anti‐Bga and anti‐Kell antibodies. Recognition of the concordant antigenic specificity of the Bga and HL‐A7 antigens led to an investigation of the potential role of this antibody in the rejection phenomenon. In the absence of serological cytotoxicity, a modified elution technique was used to directly obtain immunoglobulin from the rejected allograft. The eluate obtained displayed specificity for the Bga red blood cell antigen. The described technique affords an additional approach to the documentation of immunologically mediated graft rejection and obviates the limitations imposed by the absence of serological cytotoxicity. Emphasis is placed on the need for recognition of the relationship between red blood cell and HL‐A antigens.
A Standardized Technique for Efficient Platelet and Leukocyte Collection Using the Model 30 Blood Processor
Authors: Aisner J. , Schiffer C. A. , Wolff J. H. , Wiernik P. H.
Published: September 2010

The Model 30 Blood Processor is a safe and simple means of harvesting blood cell components. Presently cell collection depends on a visual assessment by the operator of the indistinct boundaries of cell fractions. To determine when each cell component could best be harvested, serial samples were taken from the output port at fixed intervals and the results of counts and differentials were graphed and tabulated. Studies in normal donors were done using acid‐citrate‐dextrose (ACD), 2 per cent sodium citrate in 6 per cent hydroxyethyl starch (HES), or heparin as anticoagulants. There was considerable overlap between the latter part of the platelet band, the leukocyte band and the rising hematocrit with all three anticoagulants. Normally functional lymphocytes could be harvested efficiently (˜ 80%) using ACD or heparin. Platelets could be harvested from ACD very efficiently (˜ 90%). Granulocytes could not be harvested from ACD (< 10%) since they were dispersed in the red blood cell (RBC) layer. Using HES, granulocytes could be harvested efficiently (˜ 70%) by extending collection into the RBC layer. Based on these data, a standard technique for cell collection has been devised. The flow rate is slowed to 20 ml/min and collection is carried 30 ml (90 seconds at a rate of 20 ml/min) for platelets. The RBC loss is approximately 6 to S and 2 to 3 ml/pass respectively. These studies indicate that the Model 30 is a highly efficient apparatus for blood cell separation, but the volume of blood processed is limited by the intermittent blood flow.
Blood Storage XXII. Improvement in Red Blood Cell 2,3‐DPG Levels at Six Weeks by 20 mM PO4 in CPD‐Adenine‐Inosine
Authors: Dawson R. B. , Hershey R. T. , Myers C. , Holmes S.
Published: September 2010

Inorganic phosphate has been known to assist red blood cell maintenance of ATP and in the presence of inosine to assist in the maintenance of 2,3‐DPG. High concentrations of phosphate, while helping ATP maintenance, were found to be deleterious to 2,3‐DPG maintenance in CPD‐adenine preservatives. However, in the presence of inosine, concentrations of phosphate as high as 10 mM were advantageous to 2,3‐DPG maintenance. The present study extends the observations on ATP and 2,3‐DPG maintenance in CPD‐adenine‐inosine preservatives from the previous 10 mM to 20 mM phosphate.

A high phosphate (20 mM) effect has been seen as improved maintenance of 2,3‐DPG levels during the fifth and sixth weeks of storage of whole blood at 4 C. This supports the previously reported observation of improved maintenance of 2,3‐DPG in a 10 mM phosphate preservative. This is ten times the 2 mM phosphate concentration in CPD‐adenine. In the low phosphate preservative (2 mM), 2,3‐DPG maintenance is less than that in all of the higher phosphate preservatives after the second week of storage. ATP concentrations in this experiment show good maintenance throughout six weeks of storage.
A Comparison of a Low Ionic Strength Saline Medium with Routine Methods for Antibody Detection
Authors: Wicker B. , Wallas C. H.
Published: September 2010

Antibody detection studies were undertaken in order to compare a low ionic strength (LIS) medium with a conventional albumin‐fortified isotonic medium. Tests were performed in parallel with both media at room temperature and at 37 C. A 30mM NaCl solution was used as the LIS medium and in this study this enhanced antibody reactions without causing nonspecific reactions. The LIS medium detected all of > 50 Rh and > 75 non‐Rh antibodies after 15 minutes of incubation. Often 30 to 60 minutes of incubation were required to detect these antibodies by the routine method. Several antibodies that were detected with the LIS medium after 15 minutes of incubation were either undetected or had given a nonspecific pattern of activity after 60 minutes incubation in the routine medium. When an antibody was present, the LIS medium invariably gave stronger, more clear‐cut results. it is concluded that the LIS medium is generally more sensitive than a conventional medium in detecting antibodies since such a medium will detect clinically significant antibodies after only 15 minutes incubation as well as detect antibodies missed by a conventional medium. An antibody detection system utilizing this medium has obvious applicability to a hospital transfusion service.
Structural, static and dynamic magnetic properties of Co2MnGe thin films on a sapphire a-plane substrate
Authors: Belmeguenai M. , Zighem F. , Chauveau T. , Faurie D. , Roussigné Y. , Chérif S. M. , Moch P. , Westerholt K. , Monod P.
Published: September 2010

Magnetic properties of Co2MnGe thin films of different thicknesses (13, 34, 55, 83, 100, and 200 nm), grown by rf sputtering at 400 °C on single crystal sapphire substrates, were studied using vibrating sample magnetometry and conventional or microstrip line ferromagnetic resonance. Their behavior is described assuming a magnetic energy density showing twofold and fourfold in-plane anisotropies with some misalignment between their principal directions. For all the samples, the easy axis of the fourfold anisotropy is parallel to the c-axis of the substrate while the direction of the twofold anisotropy easy axis varies from sample to sample and seems to be strongly influenced by the growth conditions. Its direction is most probably monitored by the slight unavoidable miscut angle of the Al2O3 substrate. The twofold in-plane anisotropy field Hu is almost temperature independent, in contrast with the fourfold field H4 which is a decreasing function of the temperature. Finally, we study the frequency dependence of the observed line-width of the resonant mode and we conclude to a typical Gilbert damping constant α value of 0.0065 for the 55-nm-thick film.
Excited state hydrogen transfer dynamics in substituted phenols and their complexes with ammonia: ππ∗-πσ∗ energy gap propensity and ortho-substitution effect
Authors: Pino G. A. , Oldani A. N. , Marceca E. , Fujii M. , Ishiuchi S.-I. , Miyazaki M. , Broquier M. , Dedonder C. , Jouvet C.
Published: September 2010

Lifetimes of the first electronic excited state (S1) of fluorine and methyl (o-, m-, and p-) substituted phenols and their complexes with one ammonia molecule have been measured for the 00 transition and for the intermolecular stretching σ1 levels in complexes using picosecond pump-probe spectroscopy. Excitation energies to the S1 (ππ∗) and S2 (πσ∗) states are obtained by quantum chemical calculations at the MP2 and CC2 level using the aug-cc-pVDZ basis set for the ground-state and the S1 optimized geometries. The observed lifetimes and the energy gaps between the ππ∗ and πσ∗ states show a good correlation, the lifetime being shorter for a smaller energy gap. This propensity suggests that the major dynamics in the excited state concerns an excited state hydrogen detachment or transfer (ESHD/T) promoted directly by a S1/S2 conical intersection, rather than via internal conversion to the ground-state. A specific shortening of lifetime is found in the o-fluorophenol-ammonia complex and explained in terms of the vibronic coupling between the ππ∗ and πσ∗ states occurring through the out-of-plane distortion of the C–F bond.
Perturbative studies of toroidal momentum transport using neutral beam injection modulation in the Joint European Torus: Experimental results, analysis methodology, and first principles modeling
Authors: Mantica P. , Tala T. , Ferreira J. S. , Peeters A. G. , Salmi A. , Strintzi D. , Weiland J. , Brix M. , Giroud C. , Corrigan G. , Naulin V. , Tardini G. , Zastrow K.-D. ,   JET-EFDA Contributors
Published: September 2010

Perturbative experiments have been carried out in the Joint European Torus [Fusion Sci. Technol. 53(4) (2008)] in order to identify the diffusive and convective components of toroidal momentum transport. The torque source was modulated either by modulating tangential neutral beam power or by modulating in antiphase tangential and normal beams to produce a torque perturbation in the absence of a power perturbation. The resulting periodic perturbation in the toroidal rotation velocity was modeled using time-dependent transport simulations in order to extract empirical profiles of momentum diffusivity and pinch. Details of the experimental technique, data analysis, and modeling are provided. The momentum diffusivity in the core region (0.2<ρ<0.8) was found to be close to the ion heat diffusivity (χϕ/χi∼0.7–1.7) and a significant inward momentum convection term, up to 20 m/s, was found, leading to an effective momentum diffusivity significantly lower than the ion heat diffusivity (χϕeff/χieff∼0.4). These results have significant implications on the prediction of toroidal rotation velocities in future tokamaks and are qualitatively consistent with recent developments in momentum transport theory. Detailed quantitative comparisons with the theoretical predictions of the linear gyrokinetic code GKW [A. G. Peeters et al., Comput. Phys. Commun. 180, 2650 (2009)] and of the quasilinear fluid Weiland model [J. Weiland, Collective Modes in Inhomogeneous Plasmas (IOP, Bristol, 2000)] are presented for two analyzed discharges.
Electrical conductivity and impedance spectroscopy studies of cerium based aeschynite type semiconducting oxides: CeTiMO6 (M=Nb or Ta)
Authors: Sumi S. , Rao P. Prabhakar , Deepa M. , Koshy Peter
Published: September 2010

Complex ceramic oxides, CeTiMO6 (M=Nb or Ta) having aeschynite type mineral structure were prepared by the conventional ceramic route. Complex impedance analysis in the frequency range 10 Hz–1 MHz over a wide temperature range (30–600 °C) indicates the presence of grain boundary effect along with the bulk contribution and also confirms the presence of non-Debye type of multiple relaxations in the material. The frequency dependent conductivity plots exhibit double power law dependence suggesting three types of conduction mechanisms: low frequency (10 Hz–1 kHz) conductivity owing to long range translational motion of electrons (frequency independent), mid-frequency conductivity (1–10 kHz) due to short-range hopping, and high frequency (10 kHz–1 MHz) conduction due to localized orientation hopping mechanism. The hopping model can explain the nature of the conduction mechanism completely. The electrical conductivity measurements with temperature suggest the negative temperature coefficient of resistance behavior. The activation energy studies allow insight into the nature of the conduction mechanisms.
Molecular dynamics study of the vaporization of an ionic drop
Authors: Galamba N.
Published: September 2010

The melting of a microcrystal in vacuum and subsequent vaporization of a drop of NaCl were studied through molecular dynamics simulations with the Born–Mayer–Huggins–Tosi–Fumi rigid-ion effective potential. The vaporization was studied for a single isochor at increasing temperatures until the drop completely vaporized, and gaseous NaCl formed. Examination of the vapor composition shows that the vapor of the ionic drop and gaseous NaCl are composed of neutral species, the most abundant of which, ranging from simple NaCl monomers (ion pairs) to nonlinear polymers, (NanCln)n=2–4. The enthalpies of sublimation, vaporization, and dissociation of the different vapor species are found to be in reasonable agreement with available experimental data. The decrease of the enthalpy of vaporization of the vapor species, with the radius of the drop decrease, accounts for a larger fraction of trimers and tetramers than that inferred from experiments. Further, the rhombic dimer is significantly more abundant than its linear isomer although the latter increases with the temperature. The present results suggest that both trimers and linear dimers may be important to explain the vapor pressure of molten NaCl at temperatures above 1500 K.
Ultrabroad bandwidth and matching characteristics for spinel ferrite composites with flaky fillers
Authors: Li Z. W. , Yang Z. H. , Kong L. B.
Published: September 2010

Spinel ferrite flakes Ni0.97−xZnxCo0.03Fe2O4 with x=0.5 and 0.65 are prepared for use as fillers in electromagnetic composites. The composites with the flaky fillers exhibit greatly enhanced high-frequency and attenuation properties. The complex permeability, μ0′ and μmax″, is enhanced by about 500%–700%, and the relative attenuation bandwidth WR is increased by 300%–440%, as compared to those for composites with conventional spherical fillers. WR achieves 90% of the theoretically maximum relative bandwidth. The composites with the spinel ferrite flaky fillers are powerful and potential candidates as electromagnetic attenuation materials with ultrabroad bandwidth at microwave L, S, and C bands.
Plasmonic implementation of a quantum eraser for imaging applications
Authors: Ajimo J. , Marchante M. , Krishnan A. , Bernussi A. A. , Grave de Peralta L.
Published: September 2010

We describe the use of a plasmonic version of a quantum eraser for imaging applications. Two perpendicular surface plasmon polariton (SPP) beams were excited in a glass-metal sample using a leakage radiation microscope. The polarization state of the SPP-coupled radiation leaked to the sample substrate permits to identify the path of photons along the metal-air interface of the sample. Introduction of a linear polarizer after the microscope high numerical aperture lens erases the which-path information. This enabled us to image on the microscope charge coupled device camera the interference pattern formed in the sample surface.
Field emission enhancement of ZnO nanorods assisted by decoration of ZnO nanoparticles
Authors: Huang Xin Xiong , Cheng Chung Liang , Chen Yung Ting , Chen Yang Fang
Published: September 2010

A simple approach for field emission enhancement, based on the decoration of nanoparticles on the surface of nanostructures, is reported. To illustrate our working principle, we demonstrate that the field emission performance of ZnO nanorods can be greatly enhanced by decorating ZnO nanoparticles. It is found that the field enhancement factor β can be enhanced from 1488 to 3485 and the turn-on electric field (the electric field at which the current density reaches 10 μA/cm2) can be reduced from 4.98 to 1.84 V/μm. The underlying mechanisms were attributed to the combined effects of both surface passivation and electric potential gradient generated by nanoparticles. Our approach shown here should be very useful for the development of highly efficient field emitters.
Negative thermal expansion due to negative area compressibility in TlGaSe2 semiconductor with layered crystalline structure
Authors: Seyidov MirHasan Yu. , Suleymanov Rauf A.
Published: September 2010

We conducted comparison of the original experimental data of the temperature dependences of thermal expansion in crystals with layered crystalline structure. It is shown that in most crystals with layered structure (graphite, boron nitride, GaSe, GaS, and InSe) the effect of negative thermal expansion can be explained by the specific character of the phonon spectra. It was shown, that in contrast to other crystals with layered structure, negative thermal expansion in the layers’ plane of TlGaSe2 is the result of negative area compressibility. We demonstrate that the thermal expansion of TlGaSe2 crystals can be controlled by illumination, external electric field, and thermal annealing. The nature of observed effects and a special mechanism of the negative area compressibility in TlGaSe2 crystals are discussed.
Converse piezoelectric responses in nonpiezoelectric materials implemented via asymmetric configurations of electrodes
Authors: Baskaran Sivapalan , Thiruvannamalai Sankar , Heo Hyun , Lee Ho Joon , Francis Sebastian Maliyakal , Ramachandran Narayanan , Fu John Y.
Published: September 2010

In this study, we explore the possibility of fabricating a kind of piezoelectric actuators by exploiting the converse flexoelectric effect. The phenomena of flexoelectricity demonstrate that inhomogeneous external stimuli (either mechanical or electric stimuli) can break the inversion symmetry and induce the piezoelectric response even in nonpiezoelectric materials. By using the finite element method, we approximately estimate the magnitude of the converse piezoelectric effect under such circumstances. Our simulation results have proved that the inhomogeneous electric field generated by the asymmetric configuration of electrodes can be manipulated to create the converse piezoelectric response in nonpiezoelectric dielectrics. It is also reasonable to expect that this method may provide an alternative way to overcome the negative influence of the Casimir force on micro- or nanoscale devices.
Synchronization and control in intrinsic and designed computation: An information-theoretic analysis of competing models of stochastic computation
Authors: Crutchfield James P. , Ellison Christopher J. , James Ryan G. , Mahoney John R.
Published: September 2010

We adapt tools from information theory to analyze how an observer comes to synchronize with the hidden states of a finitary, stationary stochastic process. We show that synchronization is determined by both the process’s internal organization and by an observer’s model of it. We analyze these components using the convergence of state-block and block-state entropies, comparing them to the previously known convergence properties of the Shannon block entropy. Along the way we introduce a hierarchy of information quantifiers as derivatives and integrals of these entropies, which parallels a similar hierarchy introduced for block entropy. We also draw out the duality between synchronization properties and a process’s controllability. These tools lead to a new classification of a process’s alternative representations in terms of minimality, synchronizability, and unifilarity.
Chaogates: Morphing logic gates that exploit dynamical patterns
Authors: Ditto William L. , Miliotis A. , Murali K. , Sinha Sudeshna , Spano Mark L.
Published: September 2010

Chaotic systems can yield a wide variety of patterns. Here we use this feature to generate all possible fundamental logic gate functions. This forms the basis of the design of a dynamical computing device, a chaogate, that can be rapidly morphed to become any desired logic gate. Here we review the basic concepts underlying this and present an extension of the formalism to include asymmetric logic functions.
Stationary state solutions for a gently stochastic nonlinear wave equation with ultraviolet cutoffs
Authors: Wang Yao , Thomas Lawrence E.
Published: September 2010

We consider a non-linear, one-dimensional wave equation system with finite-dimensional stochastic driving terms and with weak dissipation. A stationary process that solves the system is used to model steady-state non-equilibrium heat flow through a non-linear medium. We show existence and uniqueness of invariant measures for the system modified with ultraviolet cutoffs, and we obtain estimates for the field covariances with respect to these measures, estimates that are uniform in the cutoffs. Finally, we discuss the limit of these measures as the ultraviolet cutoffs are removed.
In situ microscopy of rapidly heated nano-Al and nano-Al/WO3 thermites
Authors: Sullivan Kyle T. , Chiou Wen-An , Fiore Richard , Zachariah Michael R.
Published: September 2010

The initiation and reaction mechanism of nano-Al and nano-Al thermites in rapid heating environments is investigated in this work. A semiconductor-based grid/stage was used, capable of in situ heating of a sample from room temperature to 1473 K, and at a rate of 106 K/s, inside an electron microscope. Nano-Al was rapidly heated in a transmission electron microscope, and before and after images indicate that the aluminum migrates through the shell, consistent with a diffusion-based mechanism. A nano-Al/WO3 composite was then heated in a scanning electron microscope. The results indicate that a reactive sintering mechanism is occurring for the nano-Al/WO3 thermite, as the products are found to be in surface contact and significantly deformed after the heating pulse.
Communication: Density-functional theory for inhomogeneous hyperbranched polymeric fluids: Polydisperse effect of degree of branching
Authors: Xu Xiaofei , Cao Dapeng
Published: September 2010

We developed a new density-functional theory (DFT) for inhomogeneous hyperbranched polymers that is able to describe the polydisperse degree of branching quantitatively. The topological contributions of the polymer chains to the Helmholtz free energy take into account the effect of triple connections that are absent in previous DFT investigations. One key advantage of the new theory is that the computational cost shows only a linear relationship with the molecular weight (rather than an exponential relationship). The practical utility of the new DFT is illustrated by investigating colloidal stability in the presence of monodisperse and polydisperse hyperbranched polymers.
How does a choice of Markov partition affect the resultant symbolic dynamics?
Authors: Teramoto Hiroshi , Komatsuzaki Tamiki
Published: September 2010

The mutual relationship among Markov partitions is investigated for one-dimensional piecewise monotonic map. It is shown that if a Markov partition is regarded as a map-refinement of the other Markov partition, that is, a concept we newly introduce in this article, one can uniquely translate a set of symbolic sequences by one Markov partition to those by the other or vice versa. However, the set of symbolic sequences constructed using Markov partitions is not necessarily translated with each other if there exists no map-refinement relation among them. By using a roof map we demonstrate how the resultant symbolic sequences depend on the choice of Markov partitions.
Virtual scanning tunneling microscopy: A local spectroscopic probe of two-dimensional electron systems
Authors: Sciambi A. , Pelliccione M. , Bank S. R. , Gossard A. C. , Goldhaber-Gordon D.
Published: September 2010

We propose a probe technique capable of performing local low-temperature spectroscopy on a two-dimensional electron system (2DES) in a semiconductor heterostructure. Motivated by predicted spatially-structured electron phases, the probe uses a charged metal tip to induce electrons to tunnel locally, directly below the tip, from a “probe” 2DES to a “subject” 2DES of interest. We test this concept with large-area (nonscanning) tunneling measurements, and predict a high spatial resolution and spectroscopic capability, with minimal influence on the physics in the subject 2DES.
Frequency shift and attenuation of hypersonic surface acoustic phonons under metallic gratings
Authors: Sadhu Jyothi , Lee J. H. , Sinha Sanjiv
Published: September 2010

Using aluminum gratings of varying duty cycles, we report picoseconds acoustics measurements of frequency shift and attenuation in surface acoustic phonons in silicon at ∼15 GHz. We observe that the frequency shifts nonlinearly with the duty cycle, particularly in the range of 0.3 to 0.5. The data deviate from the perturbation model as a sinusoidal function of the duty cycle. The attenuation peaks at 0.5 duty cycle which is in good agreement with an eigenmode analysis of the composite structure. This work elucidates the mechanism of surface acoustic phonon scattering at periodic interfaces.
High-resolution coregistered intravascular imaging with integrated ultrasound and optical coherence tomography probe
Authors: Li Xiang , Yin Jiechen , Hu Changhong , Zhou Qifa , Shung K. Kirk , Chen Zhongping
Published: September 2010

We report an integrated ultrasound (US) and optical coherence tomography (OCT) probe and system for intravascular imaging. The dual-function probe is based on a 50 MHz focused ring US transducer, with a centric hole for mounting OCT probe. The coaxial US and light beams are steered by a 45° mirror to enable coregistered US/OCT imaging simultaneously. Lateral resolution of US is improved due to focused ultrasonic beam. Mirror effects on US were investigated and in vitro imaging of a rabbit aorta has been carried out. The combined US-OCT system demonstrated high resolution in visualizing superficial arterial structures while retaining deep penetration of ultrasonic imaging.
Dye-sensitized solar cells based on anatase TiO2 nanocrystals exposing a specific lattice plane on the surface
Authors: Wen Puhong , Tao Zhuoqi , Ishikawa Yoshie , Itoh Hiroshi , Feng Qi
Published: September 2010

Dye-sensitized solar cells (DSCs) using anatase TiO2 nanocrystals exposing a specific lattice plane on the surface were studied. It was found that dye adsorption strongly depends on the lattice plane exposed on the TiO2 nanocrystal surface, which greatly affects DSC performance. TiO2 nanocrystals exposing mainly the (010) plane have a higher dye adsorption capacity and a higher Voc for DSC than normal spherical nanocrystals. TiO2 nanocrystals with a large adsorption constant Kad can yield a high Jsc. The highest Jsc (20.6 mA/cm2) was achieved by using TiO2 nanocrystals with the specific lattice plane on the surface.
Magnetic properties in graphene-graphane superlattices
Authors: Lee Joo-Hyoung , Grossman Jeffrey C.
Published: September 2010

The magnetic properties of graphene-graphane superlattices with zigzag interfaces and separately varying widths are investigated by first-principles density functional calculations. It is demonstrated that magnetic states are energetically more stable than nonmagnetic ones due to the Stoner-type instability, and that antiferromagnetic spin configuration across the graphene strip is found to be the ground state, whereas the ferromagnetic ordering becomes metastable. The magnetic moments in the ferromagnetic states show a monotonic increase and saturation with the width of the graphene strip, independent of the graphane width due to the π-character of the spin densities. These findings point toward an alternative route for graphene-based applications without requiring physical cutting as in graphene nanoribbons.
Structural origin of the intermediate phase in Ge–Se glasses
Authors: Chen G. , Inam F. , Drabold D. A.
Published: September 2010

We have conducted x-ray absorption near-edge structure (XANES) experiments on germanium selenide glasses, in search of a structural signature of the intermediate phase (IP). Quantitative analyses of the XANES spectra reveal compositional plateaus that coincide with the IP reversibility window, providing structural evidence for the IP. Molecular dynamic simulations have been performed to understand the atomistic origin of the electronic structure of the glasses. The IP originates from a competition between amorphous GeSe2 and amorphous Se clusters and produces measurable signatures. Our study provides atomistic insight into the structural origin of the IP in Ge–Se glasses.
Direct and residual effect of biochar application on mycorrhizal root colonisation, growth and nutrition of wheat
Authors: Solaiman Zakaria M. , Blackwell Paul , Abbott Lynette K. , Storer Paul
Published: September 2010

The influence of biochar (biomass-derived black carbon) on crop growth and nutrient uptake varies based on the rate of biochar applied with fertilisers. We investigated the effect of deep-banded oil mallee biochar at different rates (0, 1.5, 3.0, and 6 t/ha) with 2 types of fertiliser (non-inoculated MultiMAPS® at 30 or 55 kg/ha; inoculated Western Mineral Fertiliser at 100 kg/ha) on wheat growth at a farmer’s field in a low rainfall area of Western Australia. Wheat yield increased significantly when biochar was applied with inoculated fertiliser and 30 kg/ha non-inoculated fertiliser. Mycorrhizal colonisation in wheat roots increased significantly with biochar application with inoculated mineral fertiliser. Mycorrhizal hyphae may have improved water supply to reduce drought stress in these treatments by extending crop exploration of water from the wide inter-rows. Grain yield increases were due to better grain survival and grain fill with reduced drought stress. Early stage phosphorus uptake was not improved by mycorrhizal colonisation—phosphorus supply from the soil and applied fertiliser was already adequate. The residual effect of biochar and mineral fertilisers was assessed using a mycorrhizal bioassay for soil collected from the field trial 2 years after application of biochar. Biochar and both fertilisers increased mycorrhizal colonisation in clover bioassay plants. Deep-banded biochar provided suitable conditions for mycorrhizal fungi to colonise plant roots.
A glasshouse study on the interaction of low mineral ash biochar with nitrogen in a sandy soil
Authors: van Zwieten L. , Kimber S. , Downie A. , Morris S , Petty S. , Rust J. , Chan K. Y.
Published: September 2010

The effect of a low mineral ash biochar on biomass production and nitrogen (N) uptake into plants was tested with wheat and radish in a Yellow Earth used for commercial vegetable production. The biochar had an acid neutralising capacity <0.5% CaCO3, a total C content of 75%, and a molar H/C ratio of 0.45, indicating stability due to its aromaticity. A pot trial was established under climate-controlled conditions. Five rates of N fertiliser (0, 17, 44, 88, 177 kg N/ha) were applied as urea in combination with 5 biochar rates (0, 1.1, 2.2, 4.4, 11% w/w). Analysis of biomass production revealed a significant biochar × N fertiliser interaction. In particular, increasing biochar concentrations improved biomass production in both crop species at lower N application rates. The highest biochar application rate resulted in significantly greater accumulation of NO3
–-N in the soil and lower NH4
+-N averaged across the 5 N application rates. The biochar also decreased available P, and significantly increased microbial activity measured using the fluorescein diacetate method. Increasing N fertiliser application resulted in greater accumulation of NO3
–-N with no changes to NH4
+-N averaged across the 5 biochar application rates. Nitrogen fertiliser application did not influence microbial activity or biomass C. The trial suggests that in some cropping systems, biochar application will enable reduced N fertiliser input while maintaining productivity.
Pioneering works in biochar research, Japan
Authors: Ogawa Makoto , Okimori Yasuyuki
Published: September 2010

In Asian countries, people have a long history of using rice husk charcoal or wood ash as an agricultural soil amendment, but evidence of this has been long obscured. Since the 1980s, microbiological studies, mainly on symbiotic organisms, have been performed in Japan. Charcoal is a porous material with high water and air retention capacities and high alkalinity. Therefore, it stimulates root growth and enhances the infection of various symbiotic microbes to plant partners. The use of carbonised materials in agriculture, forestry, and construction will contribute to the sustainability of crop production, soil conservation, and carbon sequestration. Biochar-related research accumulated mainly in Japan is reviewed.