bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron-phonon interaction and its influence on reconstruction of single-walled carbon nanotube radial breathing mode spectra
Authors: Luo Zhengtang , Papadimitrakopoulos Fotios , Doorn Stephen K.
Published: February 2006

The relative electron-phonon interaction matrix elements (Mph) for 28 (n,m) semiconducting single walled carbon nanotubes (SWNTs) species were extracted from the resonance Raman cross sections of individually dispersed high-pressure CO SWNTs. The observed Mph pattern was fitted according to nanotube family [i.e., (2n+m)=const] and modality [i.e., mod(n−m,3)=1, or 2] using an empirical equation based on trigonal warping effects. The predicted Mph trends enabled significant improvement to the reconstruction of the radial breathing mode spectra, so that a better match was obtained to the experimental spectra for both dispersed and aggregated SWNTs. The latter provides an initial indication that the observed Mph trends are preserved during aggregation.
Biosensor based on magnetostrictive microcantilever
Authors: Li Suiqiong , Orona Lisa , Li Zhimin , Cheng Z.-Y.
Published: February 2006

Magnetostrictive microcantilever (MSMC) as remote biosensor platform is reported. The mass sensitivity of the MSMCs is simulated and compared with the other microcantilevers. MSMCs with a thickness of 30–35μm and different lengths and widths were fabricated from the magnetostrictive metal glass coated with a copper layer by sputtering. The resonance behavior of the MSMCs was experimentally determined. It is experimentally found that the MSMCs work well in either air or liquid. For MSMCs operated in air, a Q value of more than 500 was obtained. For MSMCs operated in water, the Q value reaches more than 30. The application of a MSMC as a biosensor platform is demonstrated by in situ detection of the yeast cells in water using the MSMC sensor.
Thermal stability of the SrTiO3∕(Ba,Sr)O stacks epitaxially grown on Si
Authors: Marchiori Chiara , Sousa M. , Guiller A. , Siegwart H. , Locquet J.-P. , Fompeyrine J. , Norga G. J. , Seo J. W.
Published: February 2006

The growth of epitaxial SrTiO3 on silicon relies on the preparation of a template layer consisting of a mixture of barium oxide and strontium oxide, (Ba,Sr)O. In this letter, the limited thermal stability of this template layer is demonstrated. X-ray photoemission spectroscopy measurements reveal that both SrTiO3∕(Ba,Sr)O and (Ba,Sr)O∕Si interfaces are susceptible to chemical reactions upon thermal treatment to an extent that is correlated with the thermal budget. These results have strong implications on the overall viability of (Ba,Sr)O as template for the growth of crystalline oxides on Si.
Efficient hole injection in organic light-emitting diodes using C60 as a buffer layer for Al reflective anodes
Authors: Lee Jun Yeob
Published: February 2006

The hole injection of the organic light-emitting diodes with Al as a reflective anode for top-emitting devices was improved by using C60 as a thin buffer layer between Al and a hole transport layer. The driving voltage of the devices with C60 buffer layer was 5.5V compared with 11V for the devices without C60 buffer layer. The decrease of interfacial energy barrier by interface dipole formation between Al and C60 contributed to the low driving voltage of the devices.
Al
Ga
N
∕
Ga
N
∕
Al
N
quantum-well field-effect transistors with highly resistive AlN epilayers
Authors: Fan Z. Y. , Li J. , Nakarmi M. L. , Lin J. Y. , Jiang H. X.
Published: February 2006

Al Ga N ∕ Ga N ∕ Al N quantum-well field-effect transistors have been demonstrated. By replacing a semi-insulating GaN epilayer with a highly resistive AlN epilayer in the device structure, parasitic conduction in the GaN epilayer, leakage current through the GaN epilayer, and the channel electrons spillover into the GaN epilayer have been completely eliminated and the drain current collapse has been reduced. The fabricated devices on sapphire substrate with 1μm gate length show a high saturation current (>1A∕mm), and excellent gate control capability with a pinch-off voltage of −6V. Even without passivation, the devices exhibit small drain current collapse (<10%) under 1μs pulse gate driving.
Degradation in photocatalytic activity induced by hydrogen-related defects in nano-LiNbO3 material
Authors: Li Zhaosheng , Yu Tao , Zou Zhigang , Ye Jinhua
Published: February 2006

As a representative example, nano-LiNbO3 is prepared by a wet-chemical method in order to enhance its photocatalytic activity through improving the surface area. The samples perform good crystallinity from powder x-ray diffraction and transmission-electron-microscope observations. It is surprising that photocatalytic activity of nano-LiNbO3 decreases with an increase of its surface area. The presence of hydrogen in the as-prepared LiNbO3 samples is detected by measuring the OH− absorption that occurred near 3500cm−1 in infrared spectra. Though the surface area of the nano-LiNbO3 samples with good crystallinity increases with a decrease of the sintered temperature, the number of hydrogen-related defects in the samples increases noticeably, thus reducing the photocatalytic activities of the nano-LiNbO3 samples.
Tunable polymeric Bragg grating filter using nanoimprint technique
Authors: Kim Do-Hwan , Chin Won-Jun , Lee Sang-Shin , Ahn Seh-Won , Lee Ki-Dong
Published: February 2006

A tunable wavelength filter was proposed and demonstrated by using the ultraviolet nanoimprint technique. It consists of a Bragg grating in polymer waveguides and a heating electrode. The creation of the grating was substantially simplified with the introduction of a smart imprint stamp containing a waveguide pattern integrated with the grating pattern. The center wavelength of the filter was successfully tuned by taking advantage of the thermooptic effect in polymers, which was induced by supplying electrical power to the electrode. For the fabricated device, a transmission dip of ∼15dB and a 3dB bandwidth of 0.8nm were obtained at the Bragg wavelength of ∼1560nm. The achieved thermooptic tuning rate was ∼0.28nm∕mW, while the center wavelength was shifted from 1560nm to 1558nm with the electrical power consumption of 7mW.
Anomalous temperature characteristics of single wide quantum well InGaN laser diode
Authors: Świetlik T. , Franssen G. , Wiśniewski P. , Krukowski S. , Łepkowski S. P. , Marona L. , Leszczyński M. , Prystawko P. , Grzegory I. , Suski T. , Porowski S. , Perlin P. , Czernecki R. , Bering-Staniszewska A. , Eliseev P. G.
Published: February 2006

By using an atypically wide quantum well (95Å) in the active layer of InGaN violet light emitting laser diode, we managed to fabricate a device characterized by very high thermal stability of the threshold current. The characteristic T0 temperature was measured to be 302K, which is the highest reported value up to date. After thermal cycling of the device, T0 drops down to the lower value of 220K. The very high value of T0 in our devices is accompanied by anomalous temperature behavior of the device slope efficiency. The slope efficiency improves with increasing temperature, reaches a maximum and then gradually decreases. This behavior we interpret as the competition between a regular increase of the thermal carrier escape and an improvement of carrier capture efficiency with an opposite temperature dependence. The latter mechanism we tentatively attribute to the temperature quenching of the ballistic transport related carrier leakage from the active region of the laser diode.
Including lameness and mastitis in a profit index for dairy cattle
Authors: Stott A. W. , Coffey M. P. , Brotherstone S.
Published: February 2006

The objective of this work was to establish economic values (EVs) of mastitis and lameness in order to enhance the current UK dairy profit index (£PLI) by including these health traits. The EVs of traits currently in £PLI were also re-evaluated to account for changes in costs/returns over time and to determine their sensitivity to changes in some of the basic assumptions used in their derivation.

Predicted transmitting abilities (PTAs) for mastitis are not available in the UK. Instead, PTAs for somatic cell count (SCC), which has a strong genetic correlation with clinical mastitis, were used to predict clinical mastitis. Similarly, PTAs for locomotion and (for bulls with no locomotion PTA) the ‘legs and feet’ composite were used to predict lameness.

The EV of mastitis was estimated at £0·83 per percent incidence, giving an index weight for SCC PTA of £0·20. The EV of lameness was estimated at £0·99 per percent incidence, giving an index weight for locomotion PTA of £1·28. The associated index weight for the ‘legs and feet’ composite was estimated to be £1·50. Economic values for all traits (production, lifespan, mastitis and lameness) were found to be sensitive to their associated price assumption but not to price assumptions of other traits in the index or to other production parameters in the model.

Better information is needed on the influence of cow age (parity) on incidence of disease and on the probability of involuntary culling to determine the appropriate balance between the EVs for longevity and health. Currently, 16% of the weight in £PLI is attributable to non-production traits. In our revised index this weight increased to 23%. Even so, selection using this index is still predicted to result in an increase in mastitis and lameness, albeit at a very low rate. This situation may be changed by the introduction of fertility into £PLI and through better information about health traits. Incorporation of consumer preference into £PLI may require traits associated with health and welfare of the cow to receive more weight than their EV would suggest in order to maintain or improve health traits in national selection programmes.
Genetic analysis of body condition in the sow during lactation, and its relation to piglet survival and growth
Authors: Grandinson K. , Rydhmer L. , Strandberg E. , Solanes F. X.
Published: February 2006

A study seeking to estimate phenotypic and genetic parameters for sow body condition around lactation and their relationship with piglet growth and survival is described. It also investigates the genetic relationship between piglet growth and survival, including both direct and maternal effects for both traits. Records were available from 24 549 Swedish Yorkshire piglets born in 2198 litters. Sows had records of weight and backfat depth at farrowing and at weaning. Piglets had individual records for weight at birth and weaning and cause of death for those that failed to survive during lactation. Mixed linear bivariate models were used to estimate correlations between traits. The models for the sow traits took into account the random effects of permanent environment and the genetic effect of the sow, whereas the models for the piglet traits included a litter effect as well as direct and maternal genetic effects. Estimated heritabilities for sow weight and backfat at farrowing and change of weight and backfat during lactation were low to moderate (0·10 to 0·47). We found significant genetic correlations between change of weight and backfat during lactation and piglet survival and growth, indicating that sows with the genetic capacity for rapid early piglet growth and high survival rate may lose more body reserves during lactation. Negative direct-maternal correlations for early piglet growth and survival imply that both the piglet and the sow trait should be included in a genetic evaluation for these traits. Genetic correlations between piglet survival and growth were not clearly favourable. Selection for the direct effect of piglet survival may lead to a decrease in early growth rate. We conclude that in a selection programme aiming at improving piglet survival and growth, attention should be paid to the sow's body condition during lactation. A high enough level of body reserves needs to be maintained in the sow if the incidence of reproductive problems and involuntary culling is not to increase.
The effect of concurrent corticosteroid induced immuno-suppression and infection with the intestinal parasite Trichostrongylus colubriformis on food intake and utilization in both immunologically naïve and competent sheep
Authors: Greer A. W. , Stankiewicz M. , Jay N. P. , McAnulty R. W. , Sykes A. R.
Published: February 2006

The nutritional cost of both the acquisition and maintenance of immunity to gastro-intestinal nematodes was investigated using immunologically naïve 5-month-old lambs and immunologically competent 17-month-old ewes. Within each age cohort, animals were either infected with the equivalent of 80 L3Trichostrongylus colubriformislarvae per kg live weight (LW) per day (IF), similarly infected and concurrently immuno-suppressed with weekly injections of 1·3 mg/kg LW of the glucocorticoid methylprednisolone acetate (ISIF), immuno-suppressed only (IS) or remained as controls (C). Body composition of all animals was estimated using X-ray computer tomography on days -14 and 76 relative to the start of infection. Body weight and faecal nematode egg counts (FEC; eggs per gram of fresh faeces (e.p.g.)) were taken weekly and blood samples for serum proteins and antibodies were obtained every 2 weeks. FEC in IF lambs peaked at 1250 e.p.g. before a typical decline as immunity developed to less than 100 e.p.g. by day 75. FEC of less than 100 e.p.g. in IF ewes indicated immunity was maintained. Successful immuno-suppression in ISIF lambs and ewes was indicated by FEC of 4000 e.p.g. on day 75 and was confirmed by comparative worm burdens and serum antibody titres. The typical reduction in voluntary food intake (VFI) as a consequence of infection was observed in IF lambs (proportionately 0·30,P< 0·001) but not in IF ewes, ISIF lambs or ISIF ewes. Gross efficiency of use of metabolizable energy for net energy deposition was reduced by proportionately 0·20 in lambs during acquisition of immunity and by 0·16 in ewes maintaining an established immunity. Infection in immuno-suppressed animals reduced efficiency by 0·05 and 0·15 for lambs and ewes, respectively. These findings allowed the hypothesis that the reduction in VFI and loss in performance in young parasitised sheep is caused by physiological signalling associated with the acquisition phase of the host immune response to infection, rather than simply the damage caused by the parasiteper se.
Genetic relationships between indicator traits and nematode parasite infection levels in 6-month-old lambs
Authors: Davies G. , Stear M. J. , Bishop S. C.
Published: February 2006

This study investigated traits that could be used to aid selective breeding for increased nematode resistance in sheep. Data were collected on approximately 1000 Scottish Blackface lambs over a 5-year period (1992–6). The animals were continually exposed to mixed nematode infection by grazing. Anthelmintic treatment was administered and blood samples were collected every 28 days from 4 to 24 weeks of age. Approximately 500 of the lambs were necropsied at 6 to 7 months of age and their worm burdens were recorded. The traits measured were the number of adult males, adult females, fifth-stage larvae and fourth-stage larvae for all species present. In addition, the mean length of adult females and the number of eggs in utero were estimated forTeladorsagia circumcincta. Several indicator traits were also measured on some of the animals, including : faecal egg counts, immunoglobulin A activity and eosinophil count as markers of the local immune response, and plasma pepsinogen activity and fructosamine concentration as indicators of the pathological consequence of infection. The heritabilities for worm length, eggs in utero and worm burden were 0.53±0.17, 0.50±0.16 and 0.13±0.10 respectively. At a mean age of 22 weeks the heritabilities for fructosamine concentration, IgA activity, eosinophil count and pepsinogen activity were 0.39±0.16, 0.57±0.15, 0.35±0.15 and 0.56±0.16 respectively. Strong negative genetic correlations (< −0.6) were often observed between necropsy traits and eosinophil count, IgA activity and pepsinogen activity. Substantial genetic correlations were also observed between fructosamine concentration and worm length (0.67) and number of fourth-stage larvae (−0.80). The genetic and environmental correlations between indicators and necropsy traits were often opposite in sign. The indicator traits studied could aid selection for increased resistance to gastrointestinal nematodes in sheep.
Starch digestion site : influence of ruminal and abomasal starch infusion on starch digestion and utilization in dairy cows
Authors: Abramson S. M. , Bruckental I. , Lipshitz L. , Moalem U. , Zamwel S. , Arieli A.
Published: February 2006

The effect of site of starch digestion on glucose metabolism in dairy cows was studied. Four multiparous Israeli-Holstein cows in mid lactation were used in a 4 × 4 Latin-square design. Average body weight of cows was 580 ± 38 kg, and average milk yield was 28 ± 3 kg/day. The cows were fitted with ruminal cannula and flexible T-cannulae in abomasum and ileum. Treatments were as follows : CON (control) : water was infused to the rumen. SR (starch-rumen) : 1.5 kg/day of maize starch solution was infused into the rumen. SA (starch-abomasum) : 1.5 kg/day of maize starch solution was infused into the abomasum. SCA (starch-casein-abomasum) : 500 g/day sodium caseinate and 1.5 kg/day of maize starch solution was infused into the abomasum. Total intake of dry matter (DM), was similar in all treatments and averaged 19.9 kg/day. Total non-structural carbohydrate (TNC) intake averaged in 6.8 kg/day. The average TNC digested in the rumen was 4.95 kg/day for CON and SR cows and 3.34 kg/day for the SA and the SCA cows. The average TNC digestion in the small intestine was 1.18 kg/day for CON and SR cows and 2.41 kg/day for the SA and SCA cows. TNC digestibility in the small intestine was highest for the SCA cows at 0.83 as compared with other treatments. Concentrations of plasma glucose and insulin were similar between treatments. No difference between treatments in total volatile fatty acid (VFA) concentration in ruminal fluids was observed. However, propionate proportion in total VFA was higher in the SR cows than in other treatments (P< 0.04). Milk yield and composition were not affected by treatments in the present study. It was concluded that the amount of dietary protein in the small intestine has a considerable effect on TNC digestibility. Under conditions of high milk production and high rumen-by-pass TNC flow, efficiency of TNC utilization might be greater since TNC is digested in the small intestine rather than in the rumen.
Assessing risks to groundwater from contaminated soils
Authors: Smith J.W.N.
Published: February 2006

Abstract. The regulatory regime for contaminated soils and groundwater in the UK is risk based. Indeed, the definition of contaminated land in UK law requires the presence, or likelihood, of significant pollution or harm before affected land meets the statutory test of being contaminated land. In dealing with contamination, a risk management approach is used that also requires the consideration of wider land‐use planning priorities, the costs and benefits of remedial action, and the goal of achieving sustainable development. A parallel risk‐based framework is adopted for polluted groundwater. The risk assessment process adopted for contaminated groundwater in the UK follows a tiered structure. A simple conceptual model is developed from desk study and site reconnaissance. This model is then used as the basis for designing a site investigation programme, the sampling being undertaken to test assumptions within the model as well as to develop it further. The Environment Agency (England & Wales) has developed a package of tools to aid this tiered approach. This paper describes the integrated risk assessment and risk management processes for contaminated groundwater in the UK, with emphasis on the tools and methods developed. It explains the importance of a conceptual understanding (or model) to all tiers of risk assessment and subsequent risk management.
Land contaminated by radioactive materials
Authors: Beresford N.A.
Published: February 2006

Abstract. Nuclear weapons' testing, mineral extraction industries and nuclear power generation are among the activities which have led to radioactively contaminated land. In the United Kingdom (UK), current activities such as the decommissioning of nuclear licensed sites and the sale of Ministry of Defence land require that the legislation, remediation and management of radioactively contaminated land be addressed. With an emphasis on the UK, this paper reviews potential management/remediation strategies for radioactively contaminated land, including consideration of the environmental mobility of potentially important radionuclides.
Exposure to Pro-Tobacco Messages: Results from the National Youth Tobacco Survey
Authors: Evans W. Douglas , Ulasevich Alec , Renaud Jeanette
Published: February 2006

Objective: To test whether race/ethnicity, gender, and grade influence self-reported exposure to pro-tobacco messages among youth.

Design: Multinomial logistic regression analyses of archival survey data (1999, 2000, and 2002 National Youth Tobacco Surveys). In separate analyses, demographic characteristics of the sample (race/ethnicity, gender, and grade) were regressed on responses to two questions regarding frequency of exposure to pro-tobacco messages. Analyses controlled for respondents' smoking status.

Main outcome measures: Reported frequency of seeing tobacco point of sales (POS) advertisements in stores and self-reported frequency of seeing actors smoking.

Results: Respondents reported generally high frequencies of seeing pro-tobacco messages either in the movies or as POS ads in stores. In comparison to Caucasian youth, African-American and Hispanic youth reported higher frequencies of seeing actors smoking. Surprisingly, non-Caucasian youth reported lower frequencies of seeing POS ads. Results by gender were mixed, but the magnitude of differences between genders was generally small. Youth in grades 6–10 were more likely to report seeing actors smoking and less likely to report seeing POS advertisements.

Conclusions: This research demonstrates that students' demographics are related to exposure to pro-tobacco messages. Given the high prevalence of smoking in movies and television, and POS advertisements, future studies should investigate the extent to which environmental exposure or psychosocial factors predict higher self-reported exposure among demographic groups.
Partnerships for Social Marketing Programs: An Example from the National Bone Health Campaign
Authors: Lefebvre R. Craig
Published: February 2006

Partnership development for national social marketing campaigns is a much copied, but poorly researched, area of practice. As part of the development of Phase II of the Centers for Disease Control's National Bone Health Campaign, several needs-assessment and market analysis activities were conducted to develop partnership strategies that were responsive to the needs of both potential campaign priority audiences and those of possible partner organizations. We discuss how the findings present strategic options for partnership recruitment and some of the key marketing issues that need to be considered in crafting an effective partnership model at the local, state and national level.
A posteriori error estimates for the Crank–Nicolson method for parabolic equations
Authors: Akrivis Georgios , Makridakis Charalambos , Nochetto Ricardo
Published: February 2006

We derive optimal order a posteriori error estimates for time discretizations by both the Crank–Nicolson and the Crank–Nicolson–Galerkin methods for linear and nonlinear parabolic equations. We examine both smooth and rough initial data. Our basic tool for deriving a posteriori estimates are second-order Crank–Nicolson reconstructions of the piecewise linear approximate solutions. These functions satisfy two fundamental properties: (i) they are explicitly computable and thus their difference to the numerical solution is controlled a posteriori, and (ii) they lead to optimal order residuals as well as to appropriate pointwise representations of the error equation of the same form as the underlying evolution equation. The resulting estimators are shown to be of optimal order by deriving upper and lower bounds for them depending only on the discretization parameters and the data of our problem. As a consequence we provide alternative proofs for known a priori rates of convergence for the Crank–Nicolson method.
Hybridized globally divergence-free LDG methods. Part I: The Stokes problem
Authors: Carrero Jesús , Cockburn Bernardo , Schötzau Dominik
Published: February 2006

We devise and analyze a new local discontinuous Galerkin (LDG) method for the Stokes equations of incompressible fluid flow. This optimally convergent method is obtained by using an LDG method to discretize a vorticity-velocity formulation of the Stokes equations and by applying a new hybridization to the resulting discretization. One of the main features of the hybridized method is that it provides a globally divergence-free approximate velocity without having to construct globally divergence-free finite-dimensional spaces; only elementwise divergence-free basis functions are used. Another important feature is that it has significantly less degrees of freedom than all other LDG methods in the current literature; in particular, the approximation to the pressure is only defined on the faces of the elements. On the other hand, we show that, as expected, the condition number of the Schur-complement matrix for this approximate pressure is of order

h

−
2

h^{-2}

in the mesh size

h
h

. Finally, we present numerical experiments that confirm the sharpness of our theoretical a priori error estimates.
The Diophantine Equation 𝑥⁴+2𝑦⁴=𝑧⁴+4𝑤⁴
Authors: Elsenhans Andreas-Stephan , Jahnel Jörg
Published: February 2006

We show that, within the hypercube

|

x

|

,

|

y

|

,

|

z

|

,

|

w

|

≤
2.5
⋅

10
6

|x|,|y|,|z|,|w| \leq 2.5 \cdot 10^6

, the Diophantine equation

x
4

+
2

y
4

=

z
4

+
4

w
4

x^4 + 2 y^4 = z^4 + 4 w^4

admits essentially one and only one nontrivial solution, namely

(
±
1

484

801
,
±
1

203

120
,
±
1

169

407
,
±
1

157

520
)

(\pm 1\,484\,801, \pm 1\,203\,120, \pm 1\,169\,407, \pm 1\,157\,520)

. The investigation is based on a systematic search by computer.
Lower bounds and stochastic optimization algorithms for uniform designs with three or four levels
Authors: Fang Kai-Tai , Maringer Dietmar , Tang Yu , Winker Peter
Published: February 2006

New lower bounds for three- and four-level designs under the centered

L
2

L_2

-discrepancy are provided. We describe necessary conditions for the existence of a uniform design meeting these lower bounds. We consider several modifications of two stochastic optimization algorithms for the problem of finding uniform or close to uniform designs under the centered

L
2

L_2

-discrepancy. Besides the threshold accepting algorithm, we introduce an algorithm named balance-pursuit heuristic. This algorithm uses some combinatorial properties of inner structures required for a uniform design. Using the best specifications of these algorithms we obtain many designs whose discrepancy is lower than those obtained in previous works, as well as many new low-discrepancy designs with fairly large scale. Moreover, some of these designs meet the lower bound, i.e., are uniform designs.
Runge-Kutta time discretizations of nonlinear dissipative evolution equations
Authors: Hansen Eskil
Published: February 2006

Global error bounds are derived for Runge-Kutta time discretizations of fully nonlinear evolution equations governed by

m
m

-dissipative vector fields on Hilbert spaces. In contrast to earlier studies, the analysis presented here is not based on linearization procedures, but on the fully nonlinear framework of logarithmic Lipschitz constants in order to extend the classical

B
B

-convergence theory to infinite-dimensional spaces. An algebraically stable Runge-Kutta method with stage order

q
q

is derived to have a global error which is at least of order

q
−
1

q-1

or

q
q

, depending on the monotonicity properties of the method.
Fast algorithms for component-by-component construction of rank-1 lattice rules in shift-invariant reproducing kernel Hilbert spaces
Authors: Nuyens Dirk , Cools Ronald
Published: February 2006

We reformulate the original component-by-component algorithm for rank-

1
1

lattices in a matrix-vector notation so as to highlight its structural properties. For function spaces similar to a weighted Korobov space, we derive a technique which has construction cost

O
(
s
n
log
⁡
(
n
)
)

O(s n \log (n))

, in contrast with the original algorithm which has construction cost

O
(
s

n
2

)

O(s n^2)

. Herein

s
s

is the number of dimensions and

n
n

the number of points (taken prime). In contrast to other approaches to speed up construction, our fast algorithm computes exactly the same quantity as the original algorithm. The presented algorithm can also be used to construct randomly shifted lattice rules in weighted Sobolev spaces.
Convolution quadrature time discretization of fractional diffusion-wave equations
Authors: Cuesta Eduardo , Lubich Christian , Palencia Cesar
Published: February 2006

We propose and study a numerical method for time discretization of linear and semilinear integro-partial differential equations that are intermediate between diffusion and wave equations, or are subdiffusive. The method uses convolution quadrature based on the second-order backward differentiation formula. Second-order error bounds of the time discretization and regularity estimates for the solution are shown in a unified way under weak assumptions on the data in a Banach space framework. Numerical experiments illustrate the theoretical results.
The efficient evaluation of the hypergeometric function of a matrix argument
Authors: Koev Plamen , Edelman Alan
Published: February 2006

We present new algorithms that efficiently approximate the hypergeometric function of a matrix argument through its expansion as a series of Jack functions. Our algorithms exploit the combinatorial properties of the Jack function, and have complexity that is only linear in the size of the matrix.
Casein Kinase II and Calcineurin Modulate TRPP Function and Ciliary Localization
Authors: Hu Jinghua , Bae Young-Kyung , Knobel Karla M. , Barr Maureen M.
Published: February 2006

Cilia serve as sensory devices in a diversity of organisms and their defects contribute to many human diseases. In primary cilia of kidney cells, the transient receptor potential polycystin (TRPP) channels polycystin-1 (PC-1) and polycystin-2 (PC-2) act as a mechanosensitive channel, with defects resulting in autosomal dominant polycystic kidney disease. In sensory cilia of Caenorhabditis elegans male-specific neurons, the TRPPs LOV-1 and PKD-2 are required for mating behavior. The mechanisms regulating TRPP ciliary localization and function are largely unknown. We identified the regulatory subunit of the serine-threonine casein kinase II (CK2) as a binding partner of LOV-1 and human PC-1. CK2 and the calcineurin phosphatase TAX-6 modulate male mating behavior and PKD-2 ciliary localization. The phospho-defective mutant PKD-2S534Alocalizes to cilia, whereas a phospho-mimetic PKD-2S534Dmutant is largely absent from cilia. Calcineurin is required for PKD-2 ciliary localization, but is not essential for ciliary gene expression, ciliogenesis, or localization of cilium structural components. This unanticipated function of calcineurin may be important for regulating ciliary protein localization. A dynamic phosphorylation-dephosphorylation cycle may represent a mechanism for modulating TRPP activity, cellular sensation, and ciliary protein localization.
Muscle fibre recruitment can respond to the mechanics of the muscle contraction
Authors: Wakeling James M , Uehli Katrin , Rozitis Antra I
Published: February 2006

This study investigates the motor unit recruitment patterns between and within muscles of the triceps surae during cycling on a stationary ergometer at a range of pedal speeds and resistances. Muscle activity was measured from the soleus (SOL), medial gastrocnemius (MG) and lateral gastrocnemius (LG) using surface electromyography (EMG) and quantified using wavelet and principal component analysis. Muscle fascicle strain rates were quantified using ultrasonography, and the muscle–tendon unit lengths were calculated from the segmental kinematics. The EMG intensities showed that the body uses the SOL relatively more for the higher-force, lower-velocity contractions than the MG and LG. The EMG spectra showed a shift to higher frequencies at faster muscle fascicle strain rates for MG: these shifts were independent of the level of muscle activity, the locomotor load and the muscle fascicle strain. These results indicated that a selective recruitment of the faster motor units occurred within the MG muscle in response to the increasing muscle fascicle strain rates. This preferential recruitment of the faster fibres for the faster tasks indicates that in some circumstances motor unit recruitment during locomotion can match the contractile properties of the muscle fibres to the mechanical demands of the contraction.
The multiple-channel cochlear implant: the interface between sound and the central nervous system for hearing, speech, and language in deaf people—a personal perspective
Authors: Clark Graeme M
Published: February 2006

The multiple-channel cochlear implant is the first sensori-neural prosthesis to effectively and safely bring electronic technology into a direct physiological relation with the central nervous system and human consciousness, and to give speech perception to severely-profoundly deaf people and spoken language to children.

Research showed that the place and temporal coding of sound frequencies could be partly replicated by multiple-channel stimulation of the auditory nerve. This required safety studies on how to prevent the effects to the cochlea of trauma, electrical stimuli, biomaterials and middle ear infection. The mechanical properties of an array and mode of stimulation for the place coding of speech frequencies were determined.

A fully implantable receiver–stimulator was developed, as well as the procedures for the clinical assessment of deaf people, and the surgical placement of the device. The perception of electrically coded sounds was determined, and a speech processing strategy discovered that enabled late-deafened adults to comprehend running speech. The brain processing systems for patterns of electrical stimuli reproducing speech were elucidated. The research was developed industrially, and improvements in speech processing made through presenting additional speech frequencies by place coding. Finally, the importance of the multiple-channel cochlear implant for early deafened children was established.
Assembly of an active translation initiation factor complex by a viral protein
Authors: Walsh Derek , Mohr Ian
Published: February 2006

Recruitment of the 40S ribosome to the 5′ end of a eukaryotic mRNA requires assembly of translation initiation factors eIF4E, the cap-binding protein, together with eIF4A and eIF4G into a complex termed eIF4F. While the translational repressor 4E-BP1 regulates binding of eIF4E to eIF4G, the forces required to construct an eIF4F complex remain unidentified. Here, we establish that the herpes simplex virus-1 (HSV-1) ICP6 polypeptide associates with eIF4G to promote eIF4F complex assembly. Strikingly, release of eIF4E from the 4E-BP1 repressor is insufficient to drive complex formation, suggesting that ICP6 is an eIF4F-assembly chaperone. This is the first example of a translation initiation factor-associated protein that promotes active complex assembly and defines a new, controllable step in the initiation of translation. Homology of the N-terminal, eIF4G-binding segment of ICP6 with cellular chaperones suggest that factors capable of interacting with eIF4G and promoting eIF4F complex assembly may play important roles in a variety of processes where translation complexes need to be remodeled or assembled on populations of newly synthesized or derepressed mRNAs, including development, differentiation, and the response to a broad spectrum of environmental cues.
An architectural map of the anaphase-promoting complex
Authors: Thornton Brian R. , Ng Tessie M. , Matyskiela Mary E. , Carroll Christopher W. , Morgan David O. , Toczyski David P.
Published: February 2006

The anaphase-promoting complex or cyclosome (APC) is an unusually complicated ubiquitin ligase, composed of 13 core subunits and either of two loosely associated regulatory subunits, Cdc20 and Cdh1. We analyzed the architecture of the APC using a recently constructed budding yeast strain that is viable in the absence of normally essential APC subunits. We found that the largest subunit, Apc1, serves as a scaffold that associates independently with two separable subcomplexes, one that contains Apc2 (Cullin), Apc11 (RING), and Doc1/Apc10, and another that contains the three TPR subunits (Cdc27, Cdc16, and Cdc23). We found that the three TPR subunits display a sequential binding dependency, with Cdc27 the most peripheral, Cdc23 the most internal, and Cdc16 between. Apc4, Apc5, Cdc23, and Apc1 associate interdependently, such that loss of any one subunit greatly reduces binding between the remaining three. Intriguingly, the cullin and TPR subunits both contribute to the binding of Cdh1 to the APC. Enzymatic assays performed with APC purified from strains lacking each of the essential subunits revealed that only cdc27Δ complexes retain detectable activity in the presence of Cdh1. This residual activity depends on the C-box domain of Cdh1, but not on the C-terminal IR domain, suggesting that the C-box mediates a productive interaction with an APC subunit other than Cdc27. We have also found that the IR domain of Cdc20 is dispensable for viability, suggesting that Cdc20 can activate the APC through another domain. We have provided an updated model for the subunit architecture of the APC.
Acetylation of Stat1 modulates NF-κB activity
Authors: Krämer Oliver H. , Baus Daniela , Knauer Shirley K. , Stein Stefan , Jäger Elke , Stauber Roland H. , Grez Manuel , Pfitzner Edith , Heinzel Thorsten
Published: February 2006

Acetylation of signaling molecules can lead to apoptosis or differentiation of carcinoma cells. The molecular mechanisms underlying these processes and the biological role of enzymes mediating the transfer or removal of an acetyl-group are currently under intense investigation. Our study shows that Stat1 is an acetylated protein. Stat1 acetylation depends on the balance between Stat1-associated histone deacetylases (HDACs) and histone acetyltransferases (HATs) such as CBP. Remarkably both inhibitors of HDACs and the cytokine interferon α alter this equilibrium and induce Stat1 acetylation. The analysis of Stat1 mutants reveals Lys 410 and Lys 413 as acetylation sites. Experiments with Stat1 mutants mimicking either constitutively acetylated or nonacetylated states show that only acetylated Stat1 is able to interact with NF-κB p65. As a consequence, p65 DNA binding, nuclear localization, and expression of anti-apoptotic NF-κB target genes decrease. These findings show how the acetylation of Stat1 regulates NF-κB activity and thus ultimately apoptosis.
Differential effect of leukaemogenic tyrosine kinases on cell motility is governed by subcellular localisation
Authors: Pierce Andrew , Lu Yuning , Hamzah Hajja G. , Thompson Suzanne , Owen‐Lynch P. J. , Whetton Anthony D. , Spooncer Elaine
Published: February 2006

The chemokine, stromal cell‐derived factor‐1 (SDF‐1) is a crucial regulator of stem cell homing and tethering, and potentiation of this pathway in leukaemias may contribute to the pathogenesis of the disease. A key second messenger in SDF‐1 signal/response coupling is phosphatidylinositol 3,4,5‐triphosphate [PtdIns(3,4,5)P3]. SDF‐1 elevated PtdIns(3,4,5)P3 levels markedly in the multipotent FDCP‐mix stem cell line. Similarly, transfection with BCR/ABL or TEL/PDGFRβ leukaemogenic tyrosine kinases chronically elevated PtdIns(3,4,5)P3 levels. However, whilst an SDF‐1 chemotactic response was observed in TEL/PDGFRβ‐transfected cells, in BCR/ABL cells this was markedly decreased, which was not due to Ras‐pathway activation. Thus, multipotent cells can respond to SDF‐1, despite chronic increases in this second messenger indicating that a discrete pool of SDF‐1‐stimulated PtdIns(3,4,5)P3 production drives the chemotactic response. To discern the mechanism for the differential effects of these oncogenes we considered subcellular localisation. As TEL/PDGFRβ has a cytosolic location whilst BCR/ABL associates with actin, we removed the actin‐binding domain from BCR/ABL. We observed relocation of BCR/ABL to the cytosol and increased SDF‐1 responses. We conclude that the localisation of BCR/ABL to the cytoskeleton is essential for effects on motility and moderating SDF‐1 responses is not essential in tyrosine kinase‐mediated leukaemic transformation.
Implantable devices for venous access: nurses' and patients' evaluation of three different port systems*
Authors: Lilienberg Annika , Bengtsson Mats , Starkhammar Hans
Published: February 2006

Implantable injection port systems are safe and convenient for long‐term venous access. The present investigation comprises nurses' and patients' evaluation of three different types of devices; Port‐A‐Cath (16.0 g), Cordis Miniport (3.8 g) for implantation in the chest wall and the PAS Port system (5.6 g) for implantation in the forearm. The devices were implanted for chemotherapy. Eighty patients and 17 nurses answered a questionnaire regarding their experience with the devices. Overall, the systems functioned well and were helpful for both patients and nurses. In the patient study few significant differences emerged. Nurses noted that the PAS Port system was more difficult to withdraw blood from (P < 0.001) and its infusion flow capacity was inferior to the two ports in the chest wall (P < 0.001). Port‐A‐Cath was judged to be the easiest system for needle insertion and the needle position was felt to be more secure (P < 0.001). Fourteen of the 17 nurses preferred Cordis Miniport for cosmetic reasons (P < 0.001). All devices functioned well. The differences in shape, size and site of implantation allow an optimum port selection for each patient. The replies in thus study expressed the need for educational programmes in order to spread the injection port concept further.
Vertical transmission in HIV infection/AIDS: a feminist perspective
Authors: Pinch Winifred J.
Published: February 2006

HIV infection and AIDS create a unique dilemma for women in their potential for vertical transmission of these conditions. Selected feminist perspectives in ontology, epistemology, and axiology are reviewed to illuminate possible social, cultural, and political circumstances of these women. Drawing both on these perspectives and various sources of data about women with HIVIAIDS, some implications for nursing complete this discussion.
An evaluative study of a community health service development
Authors: Young Kate R.
Published: February 2006

This paper describes a research study designed to evaluate a community health service development in one health authority in rural England. The study compared two types of primary care teams working towards the same objectives. Surveys of patients and staff in the health authority were conducted about a range of issues, defined by the original aims of the scheme. Measures were made of care received by people over 75 years of age, consumer satisfaction, staff experiences of the multi‐disciplinary team, job satisfaction and liaison with social services personnel. Few differences existed between the two forms of care on all of these measures. This paper contains a discussion of the findings alongside an examination of the implications for future health service developments, particularly flagship enterprises such as nursing development units. The importance of well established baseline measurements is emphasized by both the research findings and the discussion.
Long‐term care reform in Alberta, Canada: the role of the resident classification system
Authors: Armstrong‐Esther Chris A.
Published: February 2006

In 1988 the Alberta government, Canada, introduced a patient (now called resident) classification system (RCS) to measure the care requirements of residents in long‐term care facilities and provide case‐mix information so that funding could be based on resident need rather than a system of global funding. The RCS is described and issues relating to the measurement of patient resident need are discussed, together with some suggestions as to how the tool might be used in quality assurance and outcome measurement.
A comparative study of the attitudes of nursing and medical students to aspects of patient care and the nurse's role in organizing that care
Authors: Ryan Assumpta A. , McKenna Hugh P.
Published: February 2006

The purpose of this study was a comparative analysis of the attitudes of nursing and medical students toward some issues relating to patient care and the role of the nurse in organizing that care. The data were collected from I1 medical students and 19 undergraduate nursing students in their fourth or final year of study. Findings suggested that there was a statistically significant difference in the attitudes of both groups of students to the areas under investigation. Medical students were rather more cure‐oriented than nursing students who showed a care orientation. Further, the nursing students had a more positive attitude towards the need for a nursing assessment than their medical colleagues. Finally there was a marked difference in the way in which each group perceived the nurse's role, the nursing students emphasizing its independent scope while the medical students were less convinced on this issue. The conclusions suggest that both nursing and medical students need to develop a mutual understanding and respect for each other's roles if interprofessional relations are to improve.
On sources of powerlessness in nursing home life
Authors: Nyström Anne E.M. , Segesten Kerstin M.
Published: February 2006

As feelings of identity and integrity are important for old people's efforts to maintain a healthy life, experiences of powerlessness ought to be prevented. This paper describes sources of powerlessness in nursing home life. Participant observations regarding lucid, elderly patients were undertaken in two Swedish nursing home wards. The observations focused on interactions on the wards, observed patient reactions and structuraVfunctiona1 conditions of life on the wards. The constant, comparative analysis searched for events or conditions which seemed to result in reactions signifying positive or negative experiences. Tender, loving care, strong cohesion and affection between patients and personnel were typical of the observations, yet patients complained of imprisonment, powerlessness and hopelessness. Observations are reported as related to legitimate, reward, expert, informational and reference power, self‐confidence/respect and socialization. Also existential sources of powerlessness were identified. It is concluded that many factors co‐operate to create feelings of powerlessness in the patients. Empowerment measures are suggested on organizational, interactional and personal levels.