bluuebunny/crossref_metadata_2025 huggingface dataset:
Winter habitat requirements of White Eared-pheasant Crossoptilon crossoptilon and Blood Pheasant Ithaginis cruentus in south-west China
Authors: JIA FEI , WANG NAN , ZHENG GUANG-MEI
Published: October 2005

Understanding the habitat needs of White Eared-pheasant Crossoptilon crossoptilon and Blood Pheasant Ithaginis cruentus is important for their conservation. We carried out field surveys of the two pheasants around Zhujie Monastery, Daocheng County, Sichuan Province, China, using line transects. In total, 172 200 × 200 m grid squares were obtained, including 56 active and 116 inactive ones for White Eared-pheasant and 45 active and 127 inactive ones for Blood Pheasant. We analysed the occurrence of both species by logistic multiple regression. The most important variables in model 1 for White Eared-pheasant were distance to nearest permanent water, shrub cover, tree cover, tree height and herb cover. In model 2 for Blood Pheasant, distance to nearest permanent water, shrub cover, herb cover and herb height were most important. The occurrence of both pheasants was negatively related to distance to nearest permanent water and herb cover, and positively related to shrub cover. The occurrence of White Eared-pheasant was positively related to tree cover and tree height, and that of Blood Pheasant to herb height. Water, food and predation risk were the main ecological factors affecting the species' distribution. Based on the two predictive models, conservation management was proposed, to include management of selectively-logged areas and substituting other energy sources, such as electricity, for firewood.
HLA, CTLA-4 and PTPN22: the shared genetic master-key to autoimmunity?
Authors: Brand Oliver , Gough Stephen , Heward Joanne
Published: October 2005

Several genetic loci appear to be involved in susceptibility to autoimmune disease. Some loci are disease specific, whereas others appear to exert a general effect on the autoimmune disease process. Despite a large number of studies of many different diseases, consistent associations with multiple autoimmune disorders have been restricted to three gene regions: the human leukocyte antigen (HLA) class II region on chromosome 6p21, the gene encoding cytotoxic T lymphocyte-associated 4 (CTLA-4) on chromosome 2q33, and the PTPN22 gene encoding lymphoid tyrosine phosphatase (LYP) on chromosome 1p13. Each of these loci is likely to encode molecules that are crucial in the immune cascade and are actively involved in T-cell activation. Moreover, gene polymorphisms that affect function might contribute to the triggering of autoimmune disease by as-yet-unknown mechanisms. This review summarises recent developments and current understanding of the way in which molecules encoded by these susceptibility loci contribute to T-cell activation, and hypothesises how aberrant function of these molecules might trigger autoimmunity.
Characteristics of the ionospheric variability as a function of season, latitude, local time, and geomagnetic activity
Authors: Araujo‐Pradere E. A. , Fuller‐Rowell T. J. , Codrescu M. V. , Bilitza D.
Published: October 2005

An ionospheric F2 critical frequency database has been assembled to determine the variability of the F region as a function of local time, latitude, season, and geomagnetic activity. The database comprises observations from 75 ionosonde stations covering a range of geomagnetic latitude and includes 43 storm intervals. The database was previously used to develop the Storm‐Time Empirical Ionospheric Correction Model (STORM). The mean and standard deviation have been evaluated by sorting the data by local time, season (five intervals centered on equinox, solstice, and intermediate intervals), latitude (four regions each 20° wide in geomagnetic latitude), and up to eight levels of geomagnetic activity. The geomagnetic activity index was based on a weighted integral of the previous 33 hours of ap and is the same as that used by the STORM model. The database covers a full solar cycle, but insufficient information was available to sort by solar activity without compromising the estimates of variability on the other sorting parameters. About half the data were contained in the first level of geomagnetic activity, between 0 and 500 units of filtered ap corresponding to Kp ≤ 2, and half above that level. When local time dependence was included in the binning, sufficient data were available to sort into two levels of geomagnetic activity, quiet (Kp ≤ 2+) and disturbed (Kp > 3−). For all latitudes and levels of geomagnetic activity, the lowest variability was typically found in summer (10–15%), and the largest variability occurred in winter (15–40%), with equinox (10–30%) lying between the solstice extremes. The exception was low latitudes at equinox, which had surprising low variability (10%), possibly because of the weak interhemispheric flow at this time of year. At middle and low latitudes, the variability tended to increase with geomagnetic activity in winter and equinox but remained fairly constant in summer. At high latitudes, the surprising result was that in all seasons, and in winter in particular, the variability tended to decrease, probably because of the increased upwelling of neutral molecular species and stronger chemical control of the ionosphere. The data have also been used to build a table of estimated variability suitable for inclusion in the International Reference Ionosphere or any other climatological model. For periods where data were scarce or nonexistent, an estimated variability was provided on the basis of expectations of the consequences of physical processes. This was necessary to fill in the table of values in order to develop a module suitable for inclusion in the International Reference Ionosphere.
Nonplanar trapezoidal tooth log‐periodic antennas: Design and electromagnetic modeling
Authors: Ergül Özgür , Gürel Levent
Published: October 2005

Nonplanar trapezoidal tooth log‐periodic (LP) antennas are investigated by combining the wisdom of theoretical design procedures with the power of accurate numerical simulation environments. Once the theoretical design is completed, electromagnetic simulations employing accurate integral equation solvers are utilized to test and correct the original design. A two‐element array of trapezoidal tooth LP antennas is designed. The array features beam‐steering ability as a novelty, in addition to frequency independence and higher directivity. Beam steering is achieved by optimizing the excitation coefficients of the two LP antennas.
A technique for incorporating large‐scale climate information in basin‐scale ensemble streamflow forecasts
Authors: Grantz Katrina , Rajagopalan Balaji , Clark Martyn , Zagona Edith
Published: October 2005

Water managers throughout the western United States depend on seasonal forecasts to assist with operations and planning. In this study, we develop a seasonal forecasting model to aid water resources decision making in the Truckee‐Carson River System. We analyze large‐scale climate information that has a direct impact on our basin of interest to develop predictors to spring runoff. The predictors are snow water equivalent (SWE) and 500 mbar geopotential height and sea surface temperature (SST) “indices” developed in this study. We use local regression methods to provide ensemble (probabilistic) forecasts. Results show that the incorporation of climate information, particularly the 500 mbar geopotential height index, improves the skills of forecasts at longer lead times when compared with forecasts based on snowpack information alone. The technique is general and could be used to incorporate large‐scale climate information into ensemble streamflow forecasts for other river basins.
The local and global effects of Southeast Asian deforestation
Authors: Werth David , Avissar Roni
Published: October 2005

Using a global climate model (GCM), we simulate the effects of deforestation of Southeast Asia, looking at the local and remote precipitation effects of such a land‐use change. We observe a strong local effect, with a reduction in Asian precipitation that persists throughout the year. The effect of this tropical rainforest deforestation extends throughout the Tropics, but it is weaker than that seen earlier in response to Amazonian and African deforestation. The remote effect is caused by the Asian geopotential changes being spread beyond the deforested area by the large‐scale winds. The magnitude of the impact is proportional to the percentage of deforestation.
Identification of earthquake epicenter from measurements of electromagnetic pulses in the Earth
Authors: Tsutsui Minoru
Published: October 2005

We have developed a system for finding arrival directions of electromagnetic (EM) pulses detected in the earth. The system detected an intense EM pulse just when an earthquake (M5.5) occurred. In the analysis of the detected EM pulse, we first derived its frequency dispersion characteristics. Using the data of the dispersion characteristics, we obtained frequency‐dependent arrival directions of the EM pulse. Among them, an exact direction pointing toward the EM pulse source was determined. Finally, we could find the source location of the EM pulse from the estimation of its propagation distance of a waveguide mode, which has shown that the EM pulse source location was on the earthquake epicenter.
Divergent tree growth response to recent climatic warming, Lake Clark National Park and Preserve, Alaska
Authors: Driscoll William W. , Wiles Gregory C. , D'Arrigo Rosanne D. , Wilmking Martin
Published: October 2005

Many dendroclimatic studies have been conducted in Alaska to understand recent climate changes, identify past and current warming trends, and determine how climate change may influence ecosystems. Four new white spruce (Picea glauca [Moench] Voss) ring‐width chronologies from four sites along a 30 kilometer north‐south transect in the Lake Clark National Park and Preserve on the Alaskan Peninsula span a common interval from AD 1769 to 2003. Two sites show an internally consistent positive growth response to increasing April–July temperatures after 1950. The two other sites each contain two subpopulations showing varying growth responses. One subpopulation diverges from historical temperature data after 1950 and one shows increased growth consistent with warming or exceeds expected growth increases. The growth decline may be due to temperature‐induced drought stress that acts on some trees. Unprecedented climatic changes are triggering diverse growth responses between and within study sites that may greatly complicate dendroclimatic reconstructions of past climate conditions.
HF radar observations of surface circulation off Bodega Bay (northern California, USA)
Authors: Kaplan David M. , Largier John , Botsford Louis W.
Published: October 2005

Two high‐frequency radar stations (CODAR) were installed along the northern California coast in May 2001. Comparisons of radar data with acoustic Doppler current profiler (ADCP) current data and near‐surface drifter tracks indicate considerable agreement, with minimum RMS differences of order 0.05–0.15 m/s and average drifter‐HF‐radar track separation rates of 5 ± 3 km/d. Radar data resolve the three main sources of intraseasonal current variability in the area: (1) upwelling/relaxation dynamics, (2) tidal and diurnal forcing, and (3) inertial currents. Subtidal fluctuations are the largest component of variability, accounting for 45–75% of the variance. Wind‐driven dynamics are the dominant source of this subtidal variability (67% of subtidal variability). Both upwelling and relaxation periods exhibit consistent patterns of surface velocity, with nearshore currents being slower and more poleward than offshore currents, which are strongly equatorward. Analysis of tidal and inertial variability indicate that current fluctuations are polarized toward clockwise rotation and are generally weaker and more linearly polarized near the coast. M2 tidal current ellipses switch direction of rotation at the shelf break, suggesting the presence of internal tidal waves. Currents in all frequency bands are deflected and accelerated around Pt. Reyes, and there are indications of increased current variability and changes in flow direction near Cordell Bank. The presence of considerable cross‐shore and alongshore gradients in the strength and direction of surface flow patterns, and in particular weak poleward currents over the inner shelf, could have important consequences for plankton retention in the area.
A kallidin‐like peptide is a protective cardiac kinin, released by ischaemic preconditioning of rat heart
Authors: Liu Xiuxin , Lukasova Martina , Zubakova Radka , Lewicka Sabina , Hilgenfeldt Ulrich
Published: October 2005

Bradykinin is thought to play a major role among the endogenous cardioprotective candidates of ischaemic preconditioning (IPC). Little attention has been paid to the fact that in the tissue kallidin (KAL), rather than bradykinin might be the physiological mediator of the kallikrein–kinin system. In order to evaluate the importance of one or the other peptide the release and effect of both kinins has been investigated in isolated rat hearts following IPC.

Bradykinin‐ and a KAL‐like peptide were measured in the effluent of the rat isolated Langendorff heart with two different specific radioimmunoassays. The creatine kinase activity in the effluent was judged as degree of cardiac injury caused by ischaemia.

During IPC, which consists of three 5 min no‐flow and 5 min reperfusion cycles prior to the 30 min ischaemia, the bradykinin level in the effluent did not change significantly (15.4–19.4 pg ml−1). In the control group the bradykinin levels were 15.9–16.6 pg ml−1.

During IPC KAL‐like peptide (Arg1‐, instead of Lys1‐KAL), which has recently been verified by mass spectrometry, displays 5.8‐fold higher levels in the effluent and significantly increases in the same time interval from 90.4 to 189 pg ml−1.

After 30 min ischaemia the bradykinin levels in the IPC group were not significantly different to those of the control group (18.7 vs 14.4 pg ml−1). The KAL‐like peptide levels in the IPC group vs the control group were 105 vs 86.1 pg ml−1.

By the 30 min ischaemia the creatine kinase activity in the IPC group increased from 0.367 to 8.93 U l−1 (before and 10–30 min after ischaemia). In the control group during the same time period the creatine kinase levels increased from 0.277 to 34.9 U l−1. The low increase in creatine kinase activity following IPC was taken as equivalent of the cardioprotective action. A KAL antibody or HOE140 (kinin B2‐receptor antagonist) completely abolished this beneficial effect of IPC (36.6 and 53.0 U l−1) when added to the perfusion medium during the reperfusion cycles of IPC prior to the 30 min ischaemia.

Our data suggest that in rat hearts KAL‐like peptide rather than bradykinin is the physiological compound activated by IPC and acting via the cardiac kinin B2‐receptor. Thus, endogenously generated KAL‐like peptide seems to play a major role in the cardioprotection of IPC.

British Journal of Pharmacology (2005) 146, 952–957. doi:10.1038/sj.bjp.0706402
Activity of recombinant trypsin isoforms on human proteinase‐activated receptors (PAR): mesotrypsin cannot activate epithelial PAR‐1, ‐2, but weakly activates brain PAR‐1
Authors: Grishina Zoryana , Ostrowska Ewa , Halangk Walter , Sahin‐Tóth Miklós , Reiser Georg
Published: October 2005

Trypsin‐like serine proteinases trigger signal transduction pathways through proteolytic cleavage of proteinase‐activated receptors (PARs) in many tissues. Three members, PAR‐1, PAR‐2 and PAR‐4, are trypsin substrates, as trypsinolytic cleavage of the extracellular N terminus produces receptor activation. Here, the ability of the three human pancreatic trypsin isoforms (cationic trypsin, anionic trypsin and mesotrypsin (trypsin IV)) as recombinant proteins was tested on PARs.

Using fura 2 [Ca2+]imeasurements, we analyzed three human epithelial cell lines, HBE (human bronchial epithelial), A549 (human pulmonary epithelial) and HEK (human embryonic kidney)‐293 cells, which express functional PAR‐1 and PAR‐2. Human mesotrypsin failed to induce a PAR‐mediated Ca2+response in human epithelial cells even at high concentrations. In addition, mesotrypsin did not affect the magnitude of PAR activation by subsequently added bovine trypsin. In HBE cells, which like A549 cells express high PAR‐2 levels with negligible PAR‐1 levels (<11%), half‐maximal responses were seen for both cationic and anionic trypsins at about 5 nM. In the epithelial cells, mesotrypsin did not activate PAR‐2 or PAR‐1, whereas both anionic and cationic trypsins were comparable activators.

We also investigated human astrocytoma 1321N1cells, which express PAR‐1 and some PAR‐3, but no PAR‐2. High concentrations (>100 nM) of mesotrypsin produced a relatively weak Ca2+signal, apparently through PAR‐1 activation. Half‐maximal responses were observed at 60 nMmesotrypsin, and at 10–20 nMcationic and anionic trypsins.

Using a desensitization assay with PAR‐2‐AP, we confirmed that both cationic and anionic trypsin isoforms cause [Ca2+]ielevation in HBE cells mainly through PAR‐2 activation. Desensitization of PAR‐1 with thrombin receptor agonist peptide in 1321N1 cells demonstrated that all three recombinant trypsin isoforms act through PAR‐1.

Thus, the activity of human cationic and anionic trypsins on PARs was comparable to that of bovine pancreatic trypsin. Mesotrypsin (trypsin IV), in contrast to cationic and anionic trypsin, cannot activate or disable PARs in human epithelial cells, demonstrating that the receptors are no substrates for this isoenzyme. On the other hand, mesotrypsin activates PAR‐1 in human astrocytoma cells. This might play a role in protection/degeneration or plasticity processes in the human brain.

British Journal of Pharmacology(2005)146, 990–999. doi:10.1038/sj.bjp.0706410
Analysis of macroscopic ionic currents mediated by GABAρ1receptors during lanthanide modulation predicts novel states controlling channel gating
Authors: Goutman Juan D , Escobar Ariel L , Calvo Daniel J
Published: October 2005

Lanthanide‐induced modulation of GABACreceptors expressed inXenopusoocytes was studied.

We obtained two‐electrode voltage‐clamp recordings of ionic currents mediated by recombinant homomeric GABAρ1receptors and performed numerical simulations of kinetic models of the macroscopic ionic currents.

GABA‐evoked chloride currents were potentiated by La3+, Lu3+and Gd3+in the micromolar range.

Lanthanide effects were rapid, reversible and voltage independent.

The degree of potentiation was reduced by increasing GABA concentration.

Lu3+also induced receptor desensitization and decreased the deactivation rate of GABAρ1currents.

In the presence of 300 μMLu3+, dose–response curves for GABA‐evoked currents showed a significant enhancement of the maximum amplitude and an increase of the apparent affinity.

The rate of onset of TPMPA and picrotoxin antagonism of GABAρ1receptors was modulated by Lu3+.

These results suggest that the potentiation of the anionic current was the result of a direct lanthanide–receptor interaction at a site capable of allosterically modulating channel properties.

Based on kinetic schemes, which included a second open state and a nonconducting desensitized state that closely reproduced the experimental results, two nonexclusive probable models of GABAρ1channels gating are proposed.

British Journal of Pharmacology(2005)146, 1000–1009. doi:10.1038/sj.bjp.0706411
BODIPY®‐conjugated neuropeptide Y ligands: new fluorescent tools to tag Y1, Y2, Y4 and Y5 receptor subtypes
Authors: Dumont Yvan , Gaudreau Pierrette , Mazzuferi Manuela , Langlois Daniel , Chabot Jean‐Guy , Fournier Alain , Simonato Michele , Quirion Rémi
Published: October 2005

N‐terminal labelled fluorescent BODIPY®‐NPY peptide analogues were tested in Y1, Y2, Y4and Y5receptor‐binding assays performed in rat brain membrane preparations and HEK293 cells expressing the rat Y1, Y2, Y4and Y5receptors.

BODIPY®TMR/FL‐[Leu31, Pro34]NPY/PYY were able to compete for specific [125][Leu31, Pro34]PYY‐binding sites with an affinity similar to that observed for the native peptide at the Y1(Ki=1–6 nM), Y2(Ki>1000 nM), Y4(Ki=10 nM) and Y5(Ki=1–4 nM) receptor subtypes.

BODIPY®FL‐PYY(3–36) was able to compete for specific Y2(Ki=10 nM) and Y5(Ki=30 nM) binding sites, but had almost no affinity in Y1and Y4assays.

BODIPY®FL‐hPP was able to compete with high affinity (Ki; 1 and 15 nM) only in Y4and Y5receptor‐binding assays.

BODIPY®TMR‐[cPP(1–7), NPY(19–23), Ala31, Aib32, Gln34]hPP and BODIPY®TMR‐[hPP(1–17), Ala31, Aib32]NPY were potent competitors only on specific Y5‐binding sites (Ki=0.1–0.6 nM).

As expected, these fluorescent peptides inhibited forskolin‐induced cAMP accumulation, demonstrating that they retained their agonist properties.

When tested in confocal microscopy imaging, fluorescent Y1and Y5agonists internalized in a time‐dependent manner in Y1and Y5transfected cells, respectively.

These results demonstrate that BODIPY®‐conjugated NPY analogues retain their selectivity, affinity and agonist properties for the Y1, Y2, Y4and Y5receptor subtypes, respectively. Thus, they represent novel tools to study and visualize NPY receptors in living cells.

British Journal of Pharmacology(2005)146, 1069–1081. doi:10.1038/sj.bjp.0706425
Desensitization of neuronal nicotinic receptors of human neuroblastoma SH‐SY5Y cells during short or long exposure to nicotine
Authors: Sokolova Elena , Matteoni Cosetta , Nistri Andrea
Published: October 2005

Neuronal nicotinic ACh receptors (nAChRs) readily desensitize in the presence of an agonist. However, when the agonist is applied for minutes, hours or days, it is unclear how extensive desensitization is, how long it persists after agonist removal and whether nAChRs consequently change their pharmacological properties.

These issues were explored with electrophysiological studies of native receptors of voltage‐clamped human neuroblastoma SH‐SY5Y cells. Puffer pulses of nicotine (1 mM)‐evoked inward currents partly antagonized by methyllycaconitine (MLA; 10 nM) orα‐conotoxin MII (MII; 10 nM), suggesting contribution byα7 andα3 subunit containing receptors, respectively. Nicotine‐evoked currents desensitized with 150 ms time constant and fully recovered after a few s washout.

Although the current induced by 10 min application of nicotine (10 μM) decayed to baseline indicating complete desensitization, puffer applications of maximally effective doses of nicotine still generated small responses (22% of control). Similar responses to puffer‐applied nicotine were observed when nicotine was chronically incubated for 8 or 48 h. On nicotine washout, cells recovered their response amplitude within 5 min and then increased it (about 50% of untreated controls) after 30 min without altering response kinetics or sensitivity to MLA and MII.

The present results suggest that native nAChRs of SH‐SY5Y cells preserved a degree of responsiveness during chronic application of nicotine, and that they rapidly recovered on washout to generate larger responses without changes in kinetics or pharmacology. These data indicate strong compensatory mechanisms to retain nicotinic receptor function during long‐term exposure to nicotine.

British Journal of Pharmacology(2005)146, 1087–1095. doi:10.1038/sj.bjp.0706426
Minimum orbit dimension for local unitary action on n-qubit pure states
Authors: Lyons David W. , Walck Scott N.
Published: October 2005

The group of local unitary transformations partitions the space of n-qubit quantum states into orbits, each of which is a differentiable manifold of some dimension. We prove that all orbits of the n-qubit quantum state space have dimension greater than or equal to 3n∕2 for n even and greater than or equal to (3n+1)∕2 for n odd. This lower bound on orbit dimension is sharp, since n-qubit states composed of products of singlets achieve these lowest orbit dimensions.
Reduction of su(N) loop tensors to trees
Authors: Trzetrzelewski Maciej
Published: October 2005

We present a systematic method to express all su(N) invariant tensors in terms of forests, i.e., products of tree tensors.
A density-functional study of the structural, electronic, magnetic, and vibrational properties of Ti8C12 metallocarbohedrynes
Authors: Sobhy M. A. , Castleman A. W. , Sofo J. O.
Published: October 2005

Calculations are presented for the structural, electronic, and vibrational properties of the different Ti8C12 metallocarbohedrynes. (Please note that we adopt the name “metallocarbohedrynes” instead of “metallocarbohedrenes” to denote the acetylenic nature of C2 units in this class of clusters demonstrated by several contributions in literature.) The density-functional theory (DFT) calculations are performed with the all-electron projector augmented-wave method and generalized gradient approximation for the exchange-correlation functional. We study the seven low-energy isomers of the Ti8C12 metallocarbohedrynes using spin-polarized DFT, where we find a correlation between the number of rotated carbon dimers and the cohesive energy of the structure. The electronic density of states (eDOS) show that C3ν, D3d*, and D3d isomers are spin polarized. The partial eDOS shows that, depending on the dimer orientation, carbon atoms and a subgroup of the metal atoms form a covalent framework while other metal atoms are bonded to this framework more ionically. This picture is further supported by the charge density of the different structures, where we see that the Ti atoms with higher charge density show less contribution to the covalent bonding of the Ti–C framework. The vibrational spectra of the different structures are calculated using the frozen-vibration method. Also, we calculate the vibrational spectra of the C3ν and C2ν structures using molecular-dynamics simulations at two different temperatures. The results of the simulations demonstrate the local stability of the structures beyond the harmonic limit explored by the frozen-vibration method.
Continuous-wave cavity ringdown spectroscopy of the 8ν polyad of water in the 25195−25340cm−1 range
Authors: Dupré Patrick , Gherman Titus , Zobov Nikolai F. , Tolchenov Roman N. , Tennyson Jonathan
Published: October 2005

State-of-the-art experiments and calculations are used to record and assign the data obtained in the weakly absorbing blue energy region of the H2O spectrum. Continuous-wave cavity ringdown absorption spectroscopy with Doppler resolution is used to probe the range from 25 195 to 25470cm−1 with an absorption sensitivity of ∼1parts per109 (ppb)/cm. 62 lines of the polyad νOH=8 are reported, of which 43 are assigned using variational nuclear calculations. The study includes absorption line intensities (in the range of 10−28–10−26cm∕molecule) for all lines and self-broadening pressure coefficient for a few lines. The newly obtained energy levels are also reported.
Competitive charge- and energy-transfer processes following core ionization in the Na−CO cluster
Authors: Kryzhevoi Nikolai V. , Cederbaum Lorenz S.
Published: October 2005

Anion-molecule clusters constitute a very suitable class of systems for studying intermolecular (interatomic) charge-transfer (CT) processes following core ionization. A weakly bound electron of the anion in these clusters can be easily transferred to the core-ionized molecule. The screening effect of this electron may have a dramatic impact on core-level spectra and even account for a breakdown of the quasiparticle picture of core ionization. This is demonstrated here by calculating the O1s−1 and C1s−1 core ionization spectra of the Na−CO cluster using an ab initio fourth-order Green’s-function method. Interestingly, along with the CT processes in this cluster there exist also very efficient energy-transfer (ET) processes favored by the low excitation energies of Na−. These ET processes constitute an appreciable part of the electronic excitations following core ionization of Na−CO and exert thereby a strong influence on the spectra studied. The spectral features attributed to the ET processes are as pronounced as those attributed to the CT processes. Major differences in the behavior of CT and ET satellites as a function of the anion-molecule separation are found and explained. We compare also the O1s−1 core ionization spectra of the Na−CO and Na−H2O clusters. Along with a certain similarity, these spectra exhibit substantial differences which are essentially attributed to the distinct cluster geometries.
Linear stability involving the Bingham model when the yield stress approaches zero
Authors: Métivier C. , Nouar C. , Brancher J.-P.
Published: October 2005

The plane Poiseuille flow of Bingham fluid is characterized by a plug zone around the axis of the channel, where τ, the second invariant of the deviatoric stress tensor, is less than or equal to the yield stress τ0. According to the Bingham model, the plug zone moves as a rigid body with a constant velocity. The dimension of the plug zone, scaled with the width of the channel, depends only on the Bingham number, B (the ratio of the yield stress to a nominal viscous stress). The linear stability analysis of this flow as well as the Rayleigh–Bénard Poiseuille flow is performed. The numerical results are discussed essentially for the case B⪡1. By comparison with the Newtonian fluid (B=0), a discontinuous behavior of the critical conditions is observed. This discontinuity is a consequence of the linear stability analysis that allows the plug zone to remain intact.
Complex bubble dynamics in a vertical Hele-Shaw cell
Authors: Tatulchenkov A. , Cebers A.
Published: October 2005

The dynamics of a bubble rising in the vertical Hele-Shaw cell with a magnetic fluid under the action of perpendicular field is considered. By linear stability analysis it is shown that the increments of the growth of the interface perturbation modes do not depend upon the gravitational force. This result is confirmed by numerical simulation of the bubble dynamics, which is based on the boundary integral equation technique. For the numerical solution of the bubble interface evolution equation the pseudospectral technique with small scale decomposition is used. By numerical simulation of the bubble dynamics the Hopf bifurcation to the oscillatory regime is found. At larger values of the magnetic Bond number the dynamics of the bubbles becomes rather complicated.
Dip coating in the presence of a substrate-liquid interaction potential
Authors: Krechetnikov R. , Homsy G. M.
Published: October 2005

In this work we investigate theoretically the Landau-Levich problem of dip coating in the presence of a strong interaction potential normal to the substrate. This study is motivated by dip coating at very low capillary numbers when the deposited film thickness is less than 1μm and such interaction forces become important. The objective of this work is to demonstrate that in the presence of an extra body force the solution procedure differs significantly from the classical one and leads to substantial deviations from the Landau-Levich law for the entrained film thickness. In particular, attractive potentials produce film thickening and the resulting film thickness is independent of speed to lowest order. Repulsive potentials bring about more complicated behavior and lead either to films whose thickness is also independent of speed, or to a modification of the leading order constant in the classical Ca2∕3 law. Demonstration of these effects is given for a model potential. The analysis is generally applicable to many physical situations when there is an interaction between a coating liquid and a substrate, e.g., dip coating of ferromagnetic liquids on magnetic substrates, or dip coating of liquids carrying charges.
Gas-surface accommodation coefficients from viscous slip and temperature jump coefficients
Authors: McCormick N. J.
Published: October 2005

Analytical equations for the viscous slip and temperature jump coefficients for a gas flowing over a surface, obtained from a variational approach, are evaluated and compared with highly accurate numerical results for rigid sphere gas interactions. The gas-surface interaction is assumed to be governed by either the elastic-diffuse (Maxwell) one-parameter model or the Cercignani-Lampis two-parameter model. Approximate analytical equations obtained for solving the inverse problem to estimate the accommodation coefficient for the one-parameter model or the tangential momentum accommodation coefficient for the two-parameter model from an error-free measurement of the viscous slip coefficient are almost always accurate to within 3%. The corresponding estimate of the accommodation coefficient for the one-parameter model from the temperature jump coefficient is almost always accurate to within 5%.
Nanostructuring of Bi(0001) surfaces with the scanning tunneling microscope: Writing of periodic Bi structures by bias voltage pulsing
Authors: Turchanin A. , Freyland W.
Published: October 2005

Employing the scanning-tunneling-microscope pulse technique with a tungsten tip, we studied the nanostructuring of Bi (0001) surfaces at room temperature. A controlled extraction of Bi and its reversible deposition is demonstrated by simply changing the pulse polarity. Periodic nanostructures of dots, holes, lines, and grooves were written in the point and line mode of the scanner which exhibit a relatively high stability over a period of up to 22 days. Our data indicate that during the nanostructuring a Bi nanobridge forms between tungsten tip and substrate on a time scale of ∼100μs.
Dynamic lateral force microscopy with true atomic resolution
Authors: Kawai Shigeki , Kitamura Shin-ichi , Kobayashi Dai , Kawakatsu Hideki
Published: October 2005

We present frequency modulation dynamic lateral force microscopy with true atomic resolution. Torsional resonance mode of a commercially available rectangular cantilever was used to detect interaction lateral force gradients caused between the tip and the sample surface. A slight negative frequency shift of the torsional resonance frequency was observed before contact to the silicon surface. Individual adatoms in a unit cell of the Si(111)-7×7 reconstructed surface were imaged with the constant frequency shift mode. Two sets of the neighboring corner adatoms and one set of the center adatoms on the dithering direction of the tip were connected on the image. This method has a great potential to observe friction between single atoms.
Imaging suspended carbon nanotubes in field-effect transistors configured with microfabricated slits for transmission electron microscopy
Authors: Kim Taekyung , Zuo Jian-Min , Olson Eric A. , Petrov Ivan
Published: October 2005

Field-effect transistors with carbon nanotubes (CNTs) suspended across etched slits and fabricated by chemical vapor deposition have been characterized by electrical measurements and transmission electron microscopy. Two devices are examined here: One is semiconducting from two single-wall CNTs, and the other is semiconducting and metallic, with a large off current, that comes from multiple nanotubes. The study highlights the importance of structural characterization in understanding the performance of CNT devices.
980
nm
laser-diode-excited intense blue upconversion in Tm3+∕Yb3+-codoped gallate–bismuth–lead glasses
Authors: Zhang Q. Y. , Li T. , Jiang Z. H. , Ji X. H. , Buddhudu S.
Published: October 2005

Intense blue-upconversion in Tm3+∕Yb3+-codoped gallate–bismuth–lead glasses has been achieved under an excitation from a commercially available 980nm laser diode. Energy transfer processes and excited-state absorption account for the population of the G41 emitting level of the Tm3+. Although the addition of GeO2 has enhanced the glass thermal stability, the phonon mode associated with vibration of GeO2 has almost no influence on the blue-upconversion intensity and the radiative lifetime of H43 level. The dependence of the phonon energy of the host on contributions from multiphonon decay on the fluorescence has been discussed. Significant enhancement of the blue-upconversion has also been observed in gallate–bismuth–lead glasses with the incorporation of PbF2 content.
Self-fabrication of void array in fused silica by femtosecond laser processing
Authors: Toratani Eiji , Kamata Masanao , Obara Minoru
Published: October 2005

We demonstrate self-fabrication of a submicrometer-sized void array in fused silica using a 100fs 0.2–3μJ Ti:Sapphire femtosecond laser and a high 0.9 numerical aperture (NA) objective lens. The effect of the focusing conditions of NA, laser energy, and pulse number on the shape of the fabricated void was investigated. The void has a linearly drawn shape in the direction of the laser irradiation when a single pulse is irradiated and an increasing number of incident pulses resulted in the break up of the long void into multiple spherical ones, leading to a periodically aligned void array. The void shape also varied with the depth of the focus point beneath the fused silica surface, because the amount of self-focusing has a significant effect on the generation of the voids. The void shape was narrower and longer when the laser pulse was focused with the higher NA (up to 0.9) objective lens in the deeper position (up to 70μm) in the fused silica.
Haematological response to haem iron or ferrous sulphate mixed with refried black beans in moderately anaemic Guatemalan pre-school children
Authors: Schümann K , Romero-Abal ME , Mäurer A , Luck T , Beard J , Murray-Kolb L , Bulux J , Mena I , Solomons NW
Published: October 2005

Objective

Combating iron deficiency in toddlers with iron-fortified food has proved difficult in countries with phytate-rich diets. For this purpose, a new haem iron preparation was developed. The study compared changes in iron status after administration of refried beans with beans fortified with a haem iron preparation or ferrous sulphate (FeSO4).

Design

In a masked, stratified-randomised intervention trial, children received five 156-g cans of refried black beans per week for 10 consecutive weeks. The beans-only (control), FeSO4and haem iron groups were offered a cumulative dose of 155 mg, 1625 mg and 1700 mg of iron from the bean intervention, respectively. Haemoglobin (Hb) and ferritin concentrations were determined at baseline and after 5 and 10 weeks. Compliance was examined weekly.

Setting

A low-income community in Guatemala City.

Subjects

One hundred and ten children aged 12–36 months with initial Hb values between 100 and 115 g l−1.

Results

The cumulative intake of beans was approximately 80% of that offered, signifying an additional ~1300 mg of either haem or inorganic iron in the corresponding treatment groups over 10 weeks. Hb concentrations increased by the order of 7.3–11.4 g l-1during the intervention, but without significant differences across treatments. Average ferritin concentrations were unaffected by treatment assignment. However,post hocanalysis by subgroups of initial high ferritin and initial low ferritin found the Hb increments after 10 weeks in the haem iron group (13.1±7.7 g l−1) to be significantly greater than the respective increases (6.8±11.2 and 6.4±8.5 g l−1) in the inorganic iron and beans-only groups.

Conclusions

Canned refried beans are a candidate vehicle for fortificant iron. Given the improved colour and organoleptic properties imparted by haem iron added to refried beans, its additional potential for benefiting the iron status of consumers with iron deficiency may recommend it over FeSO4.
Lipid-soluble antioxidants status and some of its socio-economic determinants among pregnant Ethiopians at the third trimester
Authors: Wondmikun Yared
Published: October 2005

Objective

To determine the serum levels of three lipid-soluble antioxidants (retinol, β-carotene and α-tocopherol) in pregnant women attending an antenatal clinic (ANC) in Gondar, Ethiopia.

Design

A cross-sectional study involving laboratory determination of serum levels of retinol, α-tocopherol and β-carotene using high-performance liquid chromatography and questionnaire-based assessment of socio-economic status.

Setting

ANC of a university teaching hospital.

Subjects

Three hundred and twenty-two healthy pregnant women in their third trimester, who attended the ANC.

Results

Mean serum levels of retinol, α-tocopherol and β-carotene were found to be 1.23±0.5, 25.5±0.9 and 0.21±0.09 μmol l−1, respectively. The prevalence of vitamin A deficiency (<1.05 μmol l−1) among pregnant women was 38.5%. Women having low retinol (vitamin A) levels were highly likely to live in earth-floored and mud-walled houses, and less likely to own a house and to have a latrine.

Conclusion

The study shows that serum levels of lipid-soluble antioxidants were low among ANC attendees in northern Ethiopia. It also indicates that some socio-economic factors (such as poor housing standard) are associated with vitamin A deficiency.
Trends in food intakes in Swedish adults 1986–1999: findings from the Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Study
Authors: Krachler Benno , Eliasson Mats CE , Johansson Ingegerd , Hallmans G/ran , Lindahl Bernt
Published: October 2005

Objective

To determine changes in reported food frequency in adults between 1986 and 1999.

Design

Four consecutive cross-sectional surveys.

Setting

Counties of Norrbotten and Västerbotten, Northern Sweden.

Subjects

The Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) population, four independent cross-sectional surveys in 1986, 1990, 1994 and 1999. Randomly selected age-stratified samples of the population aged 25–64 years. Analysis is based on 2982 males and 3087 females who completed an 84-item food-frequency questionnaire.

Results

Between 1986 and 1999, average reported consumption of 3%-fat milk decreased from 42 to 7 intakes month-1 in men and from 28 to 4 intakes month-1 in women. Reported use of 1.5%-fat milk increased from 6 to 27 intakes month-1 in men and from 6 to 24 in women. Monthly intakes of potatoes and root vegetables decreased from 38 to 27 in men and from 39 to 32 in women. Consumption of pasta increased from 4 to 7 intakes month-1 in both sexes. Intakes of solid fats with 80% fat content dropped from 92 to 62 per month in men and from 78 to 52 per month in women, whereas use of 40%-fat spread increased from 12 to 22 intakes month-1 in men and from 5 to 26 in women. Monthly intakes of vegetable oil increased from 3 to 12 in men and from 3 to 15 in women. The percentage of overweight or obese individuals (body mass index >25 kg m-2) increased from 52 to 65% in men and from 41 to 52% in women (P for linear trend in all these changes, <0.001).

Conclusions

Our data indicate reduced consumption of foods with a high content of saturated fats. In spite of that, there is an unbroken trend towards increased obesity.
Stable isotope dilution techniques for assessing vitamin A status and bioefficacy of provitamin A carotenoids in humans
Authors: Furr Harold C , Green Michael H , Haskell Marjorie , Mokhtar Najat , Nestel Penelope , Newton Sam , Ribaya-Mercado Judy D , Tang Guangwen , Tanumihardjo Sherry , Wasantwisut Emorn
Published: October 2005

Vitamin A deficiency is a major global public health problem. Among the variety of techniques that are available for assessing human vitamin A status, evaluating the provitamin A nutritional values of foodstuffs and estimating human vitamin A requirements, isotope dilution provides the most accurate estimates. Although the relative expense of isotope dilution restricts its applications, it has an important function as the standard of reference for other techniques. Mathematical modelling plays an indispensable role in the interpretation of isotope dilution data. This review summarises recent applications of stable isotope methodology to determine human vitamin A status, estimate human vitamin A requirements, and calculate the bioconversion and bioefficacy of food carotenoids.
Anaemia, iron deficiency and vitamin A status among school-aged children in rural Kazakhstan
Authors: Hashizume Masahiro , Chiba Momoko , Shinohara Atsuko , Iwabuchi Shigehiro , Sasaki Satoshi , Shimoda Taeko , Kunii Osamu , Caypil Wathan , Dauletbaev Damir , Alnazarova Akmaral
Published: October 2005

Objectives

To investigate the prevalence of anaemia and iron deficiency and vitamin A status among school-aged children in rural Kazakhstan and identify factors associated with anaemia in this population.

Design

A cross-sectional design.

Setting

School-aged children in rural Kazakhstan.

Subjects

Socio-economic and anthropometric information was collected from 159 school-aged children living in the Kzyl-Orda region of Kazakhstan. Blood samples were collected and the concentrations of haemoglobin (Hb), serum iron, serum ferritin (SF), erythrocyte protoporphyrin (EP), serum retinol and β-carotene, total iron binding capacity (TIBC), transferrin saturation (TS) and other haematological indices were measured.

Results

Among the 159 children, the prevalence of anaemia and iron deficiency defined by the multiple criteria model (SF, TS and EP) was 27% and 13%, respectively. Nine per cent had iron-deficiency anaemia and 21% had serum retinol value <1.05 μmol l−1. Mean SF and serum iron concentrations and TS were significantly lower in anaemic children than in their non-anaemic peers, while TIBC and EP were significantly higher in children with anaemia. Hb was significantly correlated with serum iron and retinol concentrations. Serum retinol and SF concentrations and mean corpuscular volume were significantly correlated with Hb by multiple regression analysis.

Conclusions

Anaemia among school-aged children in rural Kazakhstan appears to be related to iron indices and vitamin A status.
The impact of a school-based nutrition education intervention on dietary intake and cognitive and attitudinal variables relating to fruits and vegetables
Authors: Anderson AS , Porteous LEG , Foster E , Higgins C , Stead M , Hetherington M , Ha M-A , Adamson AJ
Published: October 2005

Objective

To assess the impact of a school-based nutrition education intervention aimed at increasing the consumption of fruits and vegetables.

Design

The intervention programme increased the provision of fruits and vegetables in schools and provided a range of point-of-purchase marketing materials, newsletters for children and parents, and teacher information. Curriculum materials at age 6–7 and 10–11 years were also developed and utilised. Evaluation was undertaken with groups of younger (aged 6–7 years) and older (aged 10–11 years) children. Methods included 3-day dietary records with interview and cognitive and attitudinal measures at baseline, with follow-up at 9 months, in intervention and control schools.

Setting

The work was undertaken in primary schools in Dundee, Scotland.

Subjects

Subjects comprised 511 children in two intervention schools with a further 464 children from two schools acting as controls.

Results

Children (n= 64) in the intervention schools had an average increase in fruit intake (133±1.9 to 183±17.0 g day-1) that was significantly (P< 0.05) greater than the increase (100±11.7 to 107±14.2 g day-1) estimated in children (n= 65) in control schools. No other changes in food or nutrient intake were detected. Increases in scores for variables relating to knowledge about fruits and vegetables and subjective norms were also greater in the intervention than in the control group, although taste preferences for fruits and vegetables were unchanged.

Conclusions

It is concluded that a whole school approach to increasing intakes of fruits and vegetables has a modest but significant effect on cognitive and attitudinal variables and on fruit intake.