bluuebunny/crossref_metadata_2025 huggingface dataset:
A Bitter Revolution: China's Struggle with the Modern World. By RANA MITTER. [New York: Oxford University Press, 2004. 357 pp. $30.00. ISBN 0-19-280341-7.]
Authors: Weston Timothy B.
Published: March 2005

In A Bitter Revolution, Rana Mitter offers a broad-brushed interpretive essay intended for a general reader rather than a focused academic study. Because of his target audience and the expansiveness of his topic, Mitter's prose is informal and he frequently inserts textbook-style passages. Mitter intermittently offers his own illuminating readings of primary source material and throughout the work he engages with an impressive range of recently published scholarly research findings but, in the main, this book's originality lies in its integrative and sweeping narrative reading of China's modern revolutionary history.

Mitter's account is organized around a number of biographical sketches (most prominently of Zou Taofen and Du Zhongyuan) and several key historiographical contentions. Cumulatively, those contentions serve to open modern Chinese history to a range of new approaches and questions. First, Mitter argues that Chinese historians must resist the habit of centring their interpretive focus on the Communist story given the relative brevity of the Communist revolution and the fact that three very important decades have passed since its high point. This leads to the second contention – namely that in important ways contemporary Chinese politics and society share more in common with the May Fourth period than they do with the Maoist era. As Mitter sees it, the May Fourth movement, and the political and cultural pluralism of the pre-war Republican period more broadly, have remained highly relevant over the course of modern Chinese history. For this reason, he chooses to weave his narrative around that generation's passage through life during the 20th century. Thirdly, interpreters of modern Chinese history must do more to foreground the complex and multiple ways that the broader international political environment influenced China's revolutionary process over the course of the 20th century. And fourthly, it is as important to understand daily life and how it has changed over time as it is to study the large, abstract forces that shape society. In recent decades these historiographical ideas have steadily gained ground within the field of modern Chinese history, yet Mitter is among the first to build a sustained narrative statement on 20th-century China around them. In presenting this synthetic account, Mitter has performed an important and very useful service to the field.
Temporal stability and transferability of models of willingness to pay for flood control and wetland conservation
Authors: Brouwer Roy , Bateman Ian J.
Published: March 2005

This study investigates the temporal stability and transferability of dichotomous choice willingness to pay responses and their determinants from two large‐scale contingent valuation surveys in the area of flood control and wetland conservation. The study considers a time period between surveys which is more than double that considered in previous test‐retest analyses. Whereas such previous studies have reported stable values over relatively short time periods, the present study finds a statistically significant decrease in real willingness to pay over this more extended time period. Analyses of model transfer between the two survey periods indicate that models derived solely from economic‐theoretic determinants pass transferability tests. However, expanding these models to include more ad hoc, transitory factors yields nontransferable models. This provides a guide for future analyses.
Usefulness of core logging for the identification of conductive fractures in bedrock
Authors: West Anthony C. F. , Novakowksi Kent S. , Gazor Saeed
Published: March 2005

To characterize conductive fracture networks, geologists use judgement to categorize their observations of geological features into sets. To test this judgement, we propose mathematical models which relate, via parameters, tallies of sets of observations in core to transmissivity measurements made in boreholes. We show that if these models are applied to aquifers in which groundwater flow is predominantly horizontal, the major sources of error are the misalignment of core relative to hydraulic test intervals and the erroneous categorization of observations. We tallied up (1) core observations that are categorized on the basis of a descriptive code given at time of drilling and (2) breaks in core that were later categorized on the basis of their “probability of being permeable,” and we use these tallies to find least squares parameter estimates from the models applied to a set of measured transmissivities. We evaluated the success of each method to distinguish the most transmissive fractures from the least from the goodness of fits as well as from the consistency of the parameter estimates with the understood hydrogeologic role of the constituent members of each set. It was found that highly transmissive fractures in bedrock could be identified by inspection of core and that the skilled judgment used by geologists for this purpose was better encapsulated in permeability rankings than in descriptive codes and written comments.
Epitaxially influenced boundary layer model for size effect in thin metallic films
Authors: Bažant Zdeněk P. , Guo Zaoyang , Espinosa Horacio D. , Zhu Yong , Peng Bei
Published: March 2005

It is shown that the size effect recently observed by Espinosa et al., [J. Mech. Phys. Solids51, 47 (2003)] in pure tension tests on free thin metallic films can be explained by the existence of a boundary layer of fixed thickness, located at the surface of the film that was attached onto the substrate during deposition. The boundary layer is influenced by the epitaxial effects of crystal growth on the dislocation density and texture (manifested by prevalent crystal plane orientations). This influence is assumed to cause significantly elevated yield strength. Furthermore, the observed gradual postpeak softening, along with its size independence, which is observed in short film strips subjected to pure tension, is explained by slip localization, originating at notch-like defects, and by damage, which can propagate in a stable manner when the film strip under pure tension is sufficiently thin and short. For general applications, the present epitaxially influenced boundary layer model may be combined with the classical strain-gradient plasticity proposed by Gao et al., [J. Mech. Phys. Solids 47, 1239 (1999)], and it is shown that this combination is necessary to fit the test data on both pure tension and bending of thin films by one and the same theory. To deal with films having different crystal grain sizes, the Hall–Petch relation for the yield strength dependence on the grain size needs to be incorporated into the combined theory. For very thin films, in which a flattened grain fills the whole film thickness, the Hall–Petch relation needs a cutoff, and the asymptotic increase of yield strength with diminishing film thickness is then described by the extension of Nix’s model of misfit dislocations by Zhang and Zhou [J. Adv. Mater. 38, 51 (2002)]. The final result is a proposal of a general theory for strength, size effect, hardening, and softening of thin metallic films.
The melting temperature of the most common models of water
Authors: Vega C. , Sanz E. , Abascal J. L. F.
Published: March 2005

The melting temperature of ice Ih for several commonly used models of water (SPC, SPC/E,TIP3P,TIP4P, TIP4P/Ew, and TIP5P) is obtained from computer simulations at p=1bar. Since the melting temperature of ice Ih for the TIP4P model is now known [E. Sanz, C. Vega, J. L. F. Abascal, and L. G. MacDowell, Phys. Rev. Lett. 92, 255701 (2004)], it is possible to use the Gibbs–Duhem methodology [D. Kofke, J. Chem. Phys. 98, 4149 (1993)] to evaluate the melting temperature of ice Ih for other potential models of water. We have found that the melting temperatures of ice Ih for SPC, SPC/E, TIP3P, TIP4P, TIP4P/Ew, and TIP5P models are T=190K, 215K, 146K, 232K, 245K, and 274K, respectively. The relative stability of ice Ih with respect to ice II for these models has also been considered. It turns out that for SPC, SPC/E, TIP3P, and TIP5P the stable phase at the normal melting point is ice II (so that ice Ih is not a thermodynamically stable phase for these models). For TIP4P and TIP4P/Ew, ice Ih is the stable solid phase at the standard melting point. The location of the negative charge along the H–O–H bisector appears as a critical factor in the determination of the relative stability between the Ih and II ice forms. The methodology proposed in this paper can be used to investigate the effect upon a coexistence line due to a change in the potential parameters.
Effective coupling of ultraintense laser pulse to funnel-mouthed plasma waveguides
Authors: Wu Jianzhou , Cooley James H. , Antonsen Thomas M. , Milchberg Howard M.
Published: March 2005

The injection of laser pulses into hydrodynamically preformed plasma channels can be hindered by the conditions at the entrance of the channel. In particular, neutral gas and narrowing of the channel prevent efficient coupling of laser pulse entering into the channel. To solve this problem, a funnel-shaped plasma lens can be grafted onto the channel using an auxiliary formation pulse. Simulations of channel formation show that such a funnel can be made in the density ramp of a gas jet. Simulations of laser pulse propagation show that such a funnel efficiently couples pulse energy into the channel. For a backfill target with a funnel, the coupling efficiency is lower and required funnel parameters are more restrictive than for the gas jet case.
Analysis of nonselective plasma etching of AlGaN by CF4∕Ar∕Cl2
Authors: Kuryatkov V. , Borisov B. , Saxena J. , Nikishin S. A. , Temkin H. , Patibandla S. , Menon L. , Holtz M.
Published: March 2005

We report the nonselective plasma etching of epitaxial GaN:Mg, Al0.63Ga0.37N, and AlN∕Al0.08Ga0.92N short-period superlattices with various doping properties. Etching is performed using mixed CF4∕Ar feed gases in a combined inductively coupled plasma and reactive-ion etching chamber. A uniform etch rate of ∼23nm∕min is obtained for each of the compositions studied under identical conditions. This nonselective etching is also found to preserve the surface uniformity studied by atomic force microscopy and quantified using surface roughness and lateral correlation length. By adding Cl2 gas, etch rates are increased to 230–250nm∕min without degrading the surface properties.
Retrovirus envelope protein complex structure
in situ
studied by cryo-electron tomography
Authors: Förster Friedrich , Medalia Ohad , Zauberman Nathan , Baumeister Wolfgang , Fass Deborah
Published: March 2005

We used cryo-electron tomography in conjunction with single-particle averaging techniques to study the structures of frozen-hydrated envelope glycoprotein (Env) complexes on intact Moloney murine leukemia retrovirus particles. Cryo-electron tomography allows 3D imaging of viruses
in toto
at a resolution sufficient to locate individual macromolecules, and local averaging of abundant complexes substantially improves the resolution. The averaging of repetitive features in electron tomograms is hampered by a low signal-to-noise ratio and anisotropic resolution, which results from the “missing-wedge” effect. We developed an iterative 3D averaging algorithm that compensates for this effect and used it to determine the trimeric structure of Env to a resolution of 2.7 nm, at which individual domains can be resolved. Strikingly, the 3D reconstruction is shaped like a tripod in which the trimer penetrates the membrane at three distinct locations ≈4.5 nm apart from one another. The Env reconstruction allows tentative docking of the x-ray crystal structure of the receptor-binding domain. This study thus provides 3D structural information regarding the prefusion conformation of an intact unstained retrovirus surface protein.
Chromatin and RNAi factors protect the C. elegans germline against repetitive sequences
Authors: Robert Valérie J.P. , Sijen Titia , van Wolfswinkel Josien , Plasterk Ronald H.A.
Published: March 2005

Protection of genomes against invasion by repetitive sequences, such as transposons, viruses, and repetitive transgenes, involves strong and selective silencing of these sequences. During silencing of repetitive transgenes, a trans effect (“cosuppression”) occurs that results in silencing of cognate endogenous genes. Here we report RNA interference (RNAi) screens performed to catalog genes required for cosuppression in the Caenorhabditis elegans germline. We find factors with a putative role in chromatin remodeling and factors involved in RNAi. Together with molecular data also presented in this study, these results suggest that in C. elegans repetitive sequences trigger transcriptional gene silencing using RNAi and chromatin factors.
Ethnicity and adolescent mothers’ benefit from participation in home‐visitation services
Authors: Middlemiss Wendy , McGuigan William
Published: March 2005

Abstract: Early home visitation has been reported as one promising method of supporting adolescent mothers who are at risk for poor child and family outcomes. This study compared benefits of visitation for Hispanic and White non‐Hispanic adolescent mothers receiving home visits during their firstborn child's first year. Although positive benefits were identified for both groups of mothers, Hispanic mothers showed greater benefit. Explanations for these differential outcomes and related implications for practice are explored.
Distressed couples and marriage education*
Authors: DeMaria Rita M.
Published: March 2005

Abstract:Professionals generally believe that couples who choose to attend marriage education programs are not as distressed as are clinical couples and that distressed couples are not good candidates for marriage education. We examined these assumptions in 129 married couples who enrolled in a PAIRS, Practical Application of Intimate Relationship Skills (Gordon, 1994), marriage education course. Using the Enriching Relationship Issues, Communication and Happiness Inventory (Olson, 2002) typology classification with other measures of relationship adjustment, participants were classified as highly distressed, conflicted, and devitalized. Findings suggest that highly distressed married couples are among those who seek a marriage education experience. Implications for marriage education providers are discussed.
A NEW METHOD OF PRICING LOOKBACK OPTIONS
Authors: Buchen Peter , Konstandatos Otto
Published: March 2005

A new method for pricing lookback options (a.k.a. hindsight options) is presented, which simplifies the derivation of analytical formulas for this class of exotics in the Black‐Scholes framework. Underlying the method is the observation that a lookback option can be considered as an integrated form of a related barrier option. The integrations with respect to the barrier price are evaluated at the expiry date to derive the payoff of an equivalent portfolio of European‐type binary options. The arbitrage‐free price of the lookback option can then be evaluated by static replication as the present value of this portfolio. We illustrate the method by deriving expressions for generic, standard floating‐, fixed‐, and reverse‐strike lookbacks, and then show how the method can be used to price the more complex partial‐price and partial‐time lookback options. The method is in principle applicable to frameworks with alternative asset‐price dynamics to the Black‐Scholes world.
Liability Risk for Outside Directors: a Cross‐Border Analysis
Authors: Black Bernard , Cheffins Brian , Klausner Michael
Published: March 2005

Much has been said recently about the risky legal environment in which outside directors of public companies operate, especially in the USA, but increasingly elsewhere as well. Our research on outside director liability suggests, however, that directors’ fears are largely unjustified. We examine the law and lawsuit outcomes in four common law countries (Australia, Canada, Britain, and the USA) and three civil law countries (France, Germany, and Japan). The legal terrain and the risk of ‘nominal liability’(a court finds liability or the defendants agree to a settlement) differ greatly depending on the jurisdiction. But nominal liability rarely turns into ‘out‐of‐pocket liability,’ in which the directors pay personally damages or legal fees. Instead, damages and legal fees are paid by the company, directors’ and officers’(D&O) insurance, or both. The bottom line: outside directors of public companies face a very low risk of out‐of‐pocket liability. We sketch the political and market forces that produce functional convergence in outcomes across countries, despite large differences in law, and suggest reasons to think that this outcome might reflect sensible policy.
Green leaves enhance the growth and development of a stream macroinvertebrate shredder when senescent leaves are available
Authors: KOCHI KAORI , KAGAYA TAKASHI
Published: March 2005

1. Freshly fallen green leaves and flowers of terrestrial plants enter temperate streams in spring and summer, when senescent leaf litter is often scarce. These resources appear to provide good supplementary food for macroinvertebrate shredders, but have some potential shortcomings as food or case material for caddisflies.

2. To compare suitability of green leaves or flowers and senescent leaves for the growth and development of stream shredders, we reared the caddisfly Lepidostoma complicatum in the laboratory with treatments that provided larvae with senescent (oak) and green (oak or maple) leaves separately, and also together, in case the combined use of both types of leaf may benefit the shredder.

3. Larvae supplied with green leaves alone grew at 65% of the rate of those provided with senescent leaves alone, due to their lower consumption rate. No individuals given green leaves alone developed into adults, whereas 70% of the individuals given senescent leaves alone did. Green leaves may inhibit larval consumption due to their high phenol content, or they may be unsuitable for case material because they are less tough than senescent leaves.

4. Larvae supplied with both senescent and green leaves (or flowers) had a higher growth rate and developed faster, than those given senescent leaves alone, whereas the proportions of successfully emerged individuals did not differ. Lepidostoma probably benefits from the higher nitrogen content of the green leaves when used together with senescent leaves.

5. These results suggest that green leaves (or flowers) cannot serve as an alternative food resource to senescent leaves, but that they can enhance the growth and development of a Lepidostoma stream shredder if senescent leaves are also available.
Behaviour of bone marrow osteoblast‐like cells on mineral trioxide aggregate: morphology and expression of type I collagen and bone‐related protein mRNAs
Authors: Nakayama A. , Ogiso B. , Tanabe N. , Takeichi O. , Matsuzaka K. , Inoue T.
Published: March 2005

Aim  To investigate the in vitro behaviour of rat bone marrow cells (RBM) on mineral trioxide aggregate (MTA) (ProRootTM, MTA Root Canal Repair Material; Dentsply Tulsa, Tulsa, OK, USA) compared with intermediate restorative materials (IRM) (Dentsply Caulk, Milford, DE, USA).

Methodology  RBM were obtained from rat femur and were primary cultured and then subcultured. Cells were then seeded on three dishes of each material, and cultured for 3 days, after which they were evaluated morphologically using scanning (SEM) and transmission (TEM) electron microscopy. Furthermore, the calcium released from hydrated material, the cell proliferation ratio and alkaline phosphatase (ALP) activity were analysed, and the expression of type I collagen and bone‐related protein mRNAs were evaluated. The data were averaged and analysed via one‐way analysis of variance (anova) and were then compared by the Scheffe's test.

Results  SEM showed that RBM attached to MTA and had a flattened appearance without nuclear protrusions and microspikes. TEM showed that the cells attached in the same manner as the control group, but gaps larger than 2 μm were frequently seen. The calcium released from hydrated MTA was about 130 ppm after 3 days of immersion in saline. The ALP activity was similar to the control group. Cell proliferation and expression of type I collagen mRNA was significantly lower, while the expression of osteopontin mRNA was significantly higher than the control group at the third day of culture. In IRM groups, a few rounded cells were observed on the material but no living cells were seen.

Conclusions  MTA is a material of low toxicity which does not inhibit cell growth, but does suppress the differentiation of osteoblast‐like cells.
Intracanal temperature rise evaluation during the usage of the System B: replication of intracanal anatomy
Authors: Villegas J. C. , Yoshioka T. , Kobayashi Ch. , Suda H.
Published: March 2005

Aim To evaluate and determine intracanal temperature rises at 2 and 4 mm from the working length (WL) necessary to obtain proper replication of intracanal anatomy with gutta‐percha (GP) using the System B heat source during vertical condensation.

Methodology A split‐tooth model was prepared and artificial shallow depressions were cut in the buccal canal wall 2 and 4 mm from the WL. At the same level on the palatal wall holes were drilled to adapt two thermocouples. The canal was filled using GP in a vertical condensation technique by placing the System B plugger at 2 and 4 mm from the WL in groups A and B, respectively. Two control groups in which no GP was used were carried out placing the plugger 2 and 4 mm from the WL (groups A.c and B.c, respectively) and activating the heat source. Recording of temperature rise was carried out during the filling procedure for groups A and B and during activation for control groups A.c and B.c; the highest temperatures were recorded. After each filling was completed, 3 min were allowed for the GP to cool and the model divided to reveal the filling. Images of the GP were taken with a CCD camera to evaluate the presence of replication of artificial round depressions. In control groups, the temperature was recorded for 20 s after a 3 s activation of the heat source. The rise in temperature was compared between the groups individually at each level (2 or 4 mm) and statistically analysed using one‐way anova and Fisher PLSD tests at 5% of significance level (P < 0.05).

Results Mean temperature rises of 14 ± 3 and 12 ± 2 °C at 2 and 4 mm from the WL, respectively, were observed in group A fillings, and 4 ± 1 and 6 ± 1 °C at 2 and 4 mm, respectively, in group B fillings. Recordings at 2 mm showed significantly (P < 0.05) higher temperature rises with group A.c when compared with groups B and B.c. Replication of intracanal anatomy with GP was always found in group A fillings at both levels but only 4 mm from the WL in group B fillings.

Conclusions Positioning the plugger close to WL and a temperature rise of 6 °C were necessary to obtain replication of intracanal anatomy. A mean temperature rise of 4 °C at 2 mm from WL (group B) resulted in no replication of intracanal anatomy. Further studies simulating clinical conditions are necessary.
Effect of liquid and paste‐type lubricants on torque values during simulated rotary root canal instrumentation
Authors: Peters O. A. , Boessler C. , Zehnder M.
Published: March 2005

Aim  To evaluate the effects of lubrication on torque generated during rotary preparation of simulated root canals in dentine using ProFile and ProTaper Nickel‐Titanium instruments.

Methodology  Thirty‐two 3 mm thick dentine discs were used for this study. Four pilot holes were drilled perpendicularly through each disc. These simulated root canals were filled with water, aqueous 15% ethylenediamine tetraacetic acid (EDTA) or a paste‐type lubricant (Glyde). Empty canals served as controls. Peak torque values and apically directed forces of rotary instruments were measured using a specially designed testing platform. Full torsional loads over time were calculated by integration of continuous torque records. Data were compared using analyses of variance with the alpha‐type error set at 0.05.

Results  Maximum torque values using ProFile instruments were significantly (P < 0.005) reduced by the EDTA solution, whilst no reduction was observed using Glyde. With ProTaper instruments, no lubricant effects on maximum torque values were observed (P = 0.372). Full torsional loads over time were significantly reduced for both ProFile and ProTaper preparation (P < 0.005) by the use of lubrication. The two fluids performed significantly better than paste‐based Glyde. All lubricants reduced force when applied to ProTaper by mean reductions ranging from 12 to 54%, whilst Glyde lead to increased force when applied to ProFile.

Conclusions  Under the conditions of this laboratory study, lubrication appeared to be advantageous. Aqueous solutions generally performed better than the paste‐type product under investigation, which showed untoward effects when used in conjunction with a rotary instrument with a U‐shaped cross‐section (ProFile).
Optimal bedside urinalysis for the detection of proteinuria in hypertensive pregnancy: a study of diagnostic accuracy
Authors: Waugh Jason J.S. , Bell Stephen C. , Kilby Mark D. , Blackwell Claire N. , Seed Paul , Shennan Andrew H. , Halligan Aidan W.F.
Published: March 2005

Objective  To compare semi‐quantitative visual and automated methods of urine testing with fully quantitative point of care urinalysis for the detection of significant proteinuria (0.3 g/24 hours) in pregnancy complicated by hypertension.

Design  A prospective comparative study.

Setting  A large teaching maternity hospital.

Sample  One hundred and seventy‐one pregnant women referred to the obstetric day‐care unit for assessment of newly arisen hypertension.

Methods  Early morning urine specimens were tested with four dipstick techniques (Multistix 8SG visual and automated and microalbumin/creatinine ratio visual and automated; Bayer, Elkhart, USA) as well as a fully quantitative measure of the microalbumin creatinine ratio with the DCA 2000 (a point of care assay for albumin; Bayer). These results were compared to a 24‐hour urine protein measurement and measures of diagnostic accuracy/prediction are reported.

Main outcome measures  Significant proteinuria (≥0.3 g/24 hours) measured by laboratory assay.

Results  Automated dipstick urinalysis using the Clinitek 50 has significantly better predictive values for significant proteinuria (LR+ 4.27, 95% CI 2.78 to 6.56; LR− 0.225, 95% CI 0.14 to 0.37) than conventional visual dipstick urinalysis (LR+ 2.27, 95% CI 1.47 to 3.51; LR− 0.635, 95% CI 0.49 to 0.82). Dipstick microalbumin/creatinine ratio testing did not improve overall detection rates with automated or visual testing. Fully quantitative point of care measurement of albumin/creatinine ratio (ACR) was significantly better than any dipstick technique (LR+ 14.6, 95% CI 6.74 to 31.8; LR− 0.069, 95% CI 0.030 to 0.16).

Conclusions  This study confirms that in pregnancy automated dipstick urinalysis is a more accurate screening test for the detection of proteinuria than visual testing. ACR testing can offer a significant improvement over conventional urinalysis if a fully quantitative method of detection is employed that uses pregnancy‐specific thresholds. Dipstick assessment of ACR does not improve the detection rate of significant proteinuria.
Variable Resolution Spatial Interpolation Using the Simple Recursive Point Voronoi Diagram
Authors: Feick Robert , Boots Barry
Published: March 2005

This article introduces a procedure for progressively increasing the density of an initial point set that can be used as a basis for interpolating surfaces of variable resolution from sparse samples of data sites. The procedure uses the Simple Recursive Point Voronoi Diagram in which Voronoi concepts are used to tessellate space with respect to a given set of generator points. The construction is repeated every time with a new generator set, which comprises members selected from the previous generator set plus features of the current tessellation. We show how this procedure can be implemented in Arc/Info and present an illustration of its application using three known surfaces and alternative generator point configurations. Initial results suggest that the procedure has considerable potential and we discuss further methods for evaluating and extending it.
Influence of physical activity on urinary leakage in primiparous women
Authors: Eliasson K. , Nordlander I. , Larson B. , Hammarström M. , Mattsson E.
Published: March 2005

The impact of physical activity on urinary leakage (UL) has previously been considered, but not in relation to first pregnancy and delivery. The aim of this study was to describe physical activity and urinary leakage before, during and after the first childbirth. The subjects who were invited to participate in the study were taken consecutively from nine maternity clinics in the northwest part of Stockholm County, and the study group included 665 primiparous women. The mean age of the women was 28 (range 17–43) years. The women answered one questionnaire during the 36th gestation week and another 1 year post partum. Physical activity/exercises were classified according to their impact on the pelvic floor, and the women were divided into three groups: high‐impact exercise (n=327), low‐impact exercise (n=84) and the inactive group (n=254). The results showed a high intensity and frequency of physical activity in the participating primiparous women. Risk factors for UL were symptoms of a dysfunctional pelvic floor and connective tissue disorders and high‐impact physical activity before pregnancy, while low‐impact activity seemed to promote continence. If urinary leakage was present before pregnancy, it persisted in most women during pregnancy and 1 year post partum.
Short‐term high‐ vs low‐velocity isokinetic lengthening training results in greater hypertrophy of the elbow flexors in young men
Authors: Shepstone T. N. , Tang J. E. , Dallaire S. E. , Schuenke M. D. , Staron R. S. , Phillips S. M.
Published: March 2005

Study I – The effect of fast (3.66 rad/s, FAST) or slow (0.35 rad/s, SLOW) isokinetic high‐resistance muscle lengthening contractions on muscle fiber and whole muscle cross‐sectional area (CSA) of the elbow flexors was investigated in young men. Twelve subjects (23.8±2.4 years, mean±SD) performed maximal resistive lengthening isokinetic exercise with both arms for 8 weeks (3 days/week), during which they trained one arm at a FAST velocity while the contralateral arm performed an equivalent number of contractions at a SLOW velocity. Before (PRE) and after (POST) the training, percutaneous muscle biopsies were taken from the mid‐belly of the biceps brachii and analyzed for fiber type and CSA. Type I muscle fiber size increased PRE to POST (P<0.05) in both FAST and SLOW arms. Type IIa and IIx muscle fiber CSA increased in both arms, but the increases were greater in the FAST vs the SLOW trained arm (P<0.05). Elbow flexor CSA increased in FAST and SLOW arms, with the increase in the FAST arm showing a trend toward being greater (P=0.06). Maximum torque generating capacity also increased to a greater degree (P<0.05) in the FAST arm, regardless of testing velocity. Study II – In a separate study, we attempted to provide some explanation of the greater hypertrophy observed in study I by examining an indicator of protein remodeling (Z‐line streaming), which we hypothesized would be greater in the FAST condition. Nine men (21.7±2.4 years) performed an acute bout (N=30, 3 sets × 10 repetitions/set) of maximal lengthening contractions at FAST and SLOW velocities used in the training study. Biopsies revealed that FAST lengthening contractions resulted in more (185±17%; P<0.01) Z‐band streaming/mm(2) muscle, vs the SLOW arm. In conclusion, training using FAST (3.66 rad/s) lengthening contractions leads to greater hypertrophy and strength gains than SLOW (0.35 rad/s) lengthening contractions. The greater hypertrophy seen in the FAST trained arm (study I) may be related to a greater amount of protein remodeling (Z‐band streaming; study II).
Activity‐induced tissue oxygenation changes in rat cerebellar cortex: interplay of postsynaptic activation and blood flow
Authors: Offenhauser Nikolas , Thomsen Kirsten , Caesar Kirsten , Lauritzen Martin
Published: March 2005

Functional neuroimaging relies on the robust coupling between neuronal activity, metabolism and cerebral blood flow (CBF), but the physiological basis of the neuroimaging signals is still poorly understood. We examined the mechanisms of activity‐dependent changes in tissue oxygenation in relation to variations in CBF responses and postsynaptic activity in rat cerebellar cortex. To increase synaptic activity we stimulated the monosynaptic, glutamatergic climbing fibres that excite Purkinje cells via AMPA receptors. We used local field potentials to indicate synaptic activity, and recorded tissue oxygen partial pressure (Ptiss,O2) by polarographic microelectrodes, and CBF using laser‐Doppler flowmetry. The disappearance rate of oxygen in the tissue increased linearly with synaptic activity. This indicated that, without a threshold, oxygen consumption increased as a linear function of synaptic activity. The reduction in Ptiss,O2 preceded the rise in CBF. The time integral (area) of the negative Ptiss,O2 response increased non‐linearly showing saturation at high levels of synaptic activity, concomitant with a steep rise in CBF. This was accompanied by a positive change in Ptiss,O2. Neuronal nitric oxide synthase inhibition enhanced the initial negative Ptiss,O2 response (‘dip’), while attenuating the evoked CBF increase and positive Ptiss,O2 response equally. This indicates that increases in CBF counteract activity‐induced reductions in Ptiss,O2, and suggests the presence of a tissue oxygen reserve. The changes in Ptiss,O2 and CBF were strongly attenuated by AMPA receptor blockade. Our findings suggest an inverse relationship between negative Ptiss,O2 and CBF responses, and provide direct in vivo evidence for a tight coupling between activity in postsynaptic AMPA receptors and cerebellar oxygen consumption.
Interactions between histamine and bradykinin in stimulation of ischaemically sensitive cardiac afferents in felines
Authors: Fu Liang‐Wu , Longhurst John C.
Published: March 2005

Cardiac spinal afferents are activated during myocardial ischaemia. Our previous studies have shown that during ischaemia, histamine and bradykinin (BK) stimulate cardiac spinal afferents. Because the two mediators are released together during ischaemia, the present study examined the interactions between these two mediators with respect to their influence on ischaemically sensitive cardiac afferents. Single‐unit cardiac afferent activity was recorded from the left sympathetic chain or rami communicantes (T2–T5) in anaesthetized cats. Fifty‐five ischaemically sensitive cardiac afferents (conduction velocity (CV) = 0.2−5.6 m s−1, 8 Aδ‐ and 47 C‐fibres) were identified. Administration of histamine (10 μg kg−1) and BK (1 μg) in combination into the left atrium (LA) caused an additive response in 16 afferents compared with administration of either BK or histamine alone (2.62 ± 0.39 versus 1.67 ± 0.20 versus 1.24 ± 0.23 impulses s−1 (imp s−1), BK + histamine versus BK versus histamine). To further evaluate interactions between these mediators, we observed that injection of histamine (10 μg kg−1, LA) 4 min after the administration of BK (1 μg, LA) induced a significantly larger cardiac afferent response than the response to histamine before BK (1.24 ± 0.23 versus 1.96 ± 0.39 imp s−1, before versus after, n= 10). In contrast, six other afferents responded reproducibly to repeated injections of histamine (10 μg kg−1, LA) in the absence of BK. BK sensitization of the afferent response to histamine lasted for less than 10 min. Cyclooxygenase blockade with indomethacin (5 mg kg−1, i.v.) abolished BK sensitization of the response to histamine (1.09 ± 0.11 versus 1.11 ± 0.10 imp s−1, n= 10). Conversely, the response of most (7/9) cardiac afferents to repeat application of BK (1 μg, LA) 4 min after histamine (10 μg kg−1, LA) was attenuated compared with the BK response before histamine (1.84 ± 0.25 versus 1.31 ± 0.18 imp s−1, before versus after, P < 0.05). Repeat BK (1 μg, LA) induced a consistent response in five other afferents in the absence of histamine. Thus, BK interacts with histamine, and together they cause a larger response than either one alone. BK sensitizes cardiac afferents responding to histamine in a time‐dependent fashion, and the BK sensitization effect is dependent on an intact cyclooxygenase pathway. Conversely, histamine reduces the response of most afferents to BK.
Paradoxical SR Ca2+ release in guinea‐pig cardiac myocytes after β‐adrenergic stimulation revealed by two‐photon photolysis of caged Ca2+
Authors: Lindegger Nicolas , Niggli Ernst
Published: March 2005

In heart muscle the amplification and shaping of Ca2+ signals governing contraction are orchestrated by recruiting a variable number of Ca2+ sparks. Sparks reflect Ca2+ release from the sarcoplasmic reticulum (SR) via Ca2+ release channels (ryanodine receptors, RyRs). RyRs are activated by Ca2+ influx via L‐type Ca2+ channels with a specific probability that may depend on regulatory mechanisms (e.g. β‐adrenergic stimulation) or diseased states (e.g. heart failure). Changes of RyR phosphorylation may be critical for both regulation and impaired function in disease. Using UV flash photolysis of caged Ca2+ and short applications of caffeine in guinea‐pig ventricular myocytes, we found that Ca2+ release signals on the cellular level were largely governed by global SR content. During β‐adrenergic stimulation resting myocytes exhibited smaller SR Ca2+ release signals when activated by photolysis (62.3% of control), resulting from reduced SR Ca2+ content under these conditions (58.6% of control). In contrast, local signals triggered with diffraction limited two‐photon photolysis displayed the opposite behaviour, exhibiting a larger Ca2+ release (164% of control) despite reduced global and local SR Ca2+ content. This apparent paradox implies changes of RyR open probabilities after β‐adrenergic stimulation, enhancing local regenerativity and reliability of Ca2+ signalling. Thus, our results underscore the importance of phosphorylation of RyRs (or of a related protein), as a regulatory physiological mechanism that may also provide new therapeutic avenues to recover impaired Ca2+ signalling during cardiac disease.
The Climate Change Commitment
Authors: Wigley T. M. L.
Published: March 2005

Even if atmospheric composition were fixed today, global-mean temperature and sea level rise would continue due to oceanic thermal inertia. These constant-composition (CC) commitments and their uncertainties are quantified. Constant-emissions (CE) commitments are also considered. The CC warming commitment could exceed 1°C. The CE warming commitment is 2° to 6°C by the year 2400. For sea level rise, the CC commitment is 10 centimeters per century (extreme range approximately 1 to 30 centimeters per century) and the CE commitment is 25 centimeters per century (7 to 50 centimeters per century). Avoiding these changes requires, eventually, a reduction in emissions to substantially below present levels. For sea level rise, a substantial long-term commitment may be impossible to avoid.
PASSIVITY OF GROUND STATES OF QUANTUM SYSTEMS
Authors: WRESZINSKI WALTER F.
Published: March 2005

We consider a quantum system described by a concrete C*-algebra acting on a Hilbert space ℋ with a vector state ω induced by a cyclic vector Ω and a unitary evolution Utsuch that UtΩ = Ω, ∀t ∈ ℝ. It is proved that this vector state is a ground state if and only if it is non-faithful and completely passive. This version of a result of Pusz and Woronowicz is reviewed, emphasizing other related aspects: passivity from the point of view of moving observers and stability with respect to local perturbations of the dynamics.
Acute insulin-induced elevations of circulating leptin and feeding inhibition in lean but not obese rats
Authors: Singh Kimberly A. , Boozer Carol N. , Vasselli Joseph R.
Published: March 2005

Insulin has been shown to stimulate leptin mRNA expression acutely in rat adipose tissue, but its short-term effects on circulating leptin levels, and subsequent feeding behavior, have not been well described. We used 11-mo-old female selectively bred obesity-resistant (OR) and obesity-prone (OP) Sprague-Dawley rats maintained on laboratory chow to investigate this question. At testing, body weights and basal leptin levels of the OP rats were significantly elevated compared with the OR rats. In the 3-h fasted state, injection of 2.0 U insulin/kg ip resulted in significant elevations of plasma leptin at 4 h postinjection in both OP and OR groups ( hour 4, +2.50 and +5.98 ng/ml, respectively). In separate feeding tests with the same groups, intake of laboratory chow pellets was significantly inhibited during hours 2–4 after 2.0 U/kg of insulin in the OR (−80.1%, P < 0.05), but not in the OP group, compared with intake after saline injections. In feeding tests with palatable moderately high-fat pellets after 2.0 and 3.0 U insulin/kg ip, significant decreases between hours 2 and 4 in intake were seen in the OR group only (−41.0 and −68.3%, respectively). Thus feeding inhibition coincides with insulin-induced elevations of plasma leptin in lean but not obese Sprague-Dawley rats. Our data suggest that elevations of leptin within the physiological range may contribute to short-term inhibition of food intake in rats and that this process may be stimulated by feeding-related insulin release.
Intrapulmonary arteriovenous shunts of >15 μm in diameter probably do not contribute to arterial hypoxemia in maximally exercising Thoroughbred horses
Authors: Manohar Murli , Goetz Thomas E.
Published: March 2005

The present study examined whether Thoroughbred horses performing strenuous exercise exhibit intrapulmonary arteriovenous shunting that may contribute to the observed arterial hypoxemia. Experiments were carried out on seven healthy, exercise-trained Thoroughbreds at rest, maximal exercise (galloping at 14 m/s on a 3.5% uphill grade for 120 s), and submaximal exertion (8 m/s on a 3.5% uphill grade for 150 s). Along with blood gas/hemodynamic parameters, intrapulmonary arteriovenous shunting was studied by injecting 15-μm-diameter microspheres, labeled with different stable isotopes, into the right atrium while simultaneous blood samples were being withdrawn at a constant rate from the pulmonary artery and the aorta. Arterial hypoxemia was observed only during maximal exercise. Also, despite significant pulmonary arterial hypertension during submaximal and maximal exertion, 15-μm microspheres did not traverse the pulmonary microcirculation to appear in the aortic blood. Thus our findings did not support a role for intrapulmonary arteriovenous shunts of >15 μm in diameter in the exercise-induced arterial hypoxemia in racehorses. Interestingly, our observation that, in going from 30 to 120 s of maximal exertion, arterial O2 tension had remained unchanged despite significant reductions in mixed venous blood O2 tension, hemoglobin-O2 saturation, and O2 content also discounts the importance of intrapulmonary arteriovenous shunts in causing arterial hypoxemia. This is because, assuming that a constant fraction of total pulmonary blood flow bypasses the gas-exchange areas of the equine lungs via intrapulmonary arteriovenous shunts during 30–120 s of maximal exertion, the observed significant reductions in mixed venous blood oxygenation should cause a significant reduction in arterial O2 tension, which was not the case in our horses. Thus it is suggested that intrapulmonary arteriovenous shunting probably does not contribute to the exercise-induced arterial hypoxemia in racehorses.
Lesion Patterns and Etiology of Ischemia in Superior Cerebellar Artery Territory Infarcts
Authors: Kumral Emre , Kısabay Ayşın , Ataç Ceyla
Published: March 2005

Background and Purpose: Infarcts in the territory of superior cerebellar artery (SCA) are uncommon. The clinical, and etiological mechanisms of different infarct patterns of SCA are not well known. Diffusion-weighted imaging (DWI) is superior to conventional magnetic resonance imaging for detecting acute small and multiple ischemic lesions. Methods: We studied 60 patients with lesions involving SCA territory proved by DWI, which have been selected from 3,800 patients with first ischemic stroke consecutively admitted to our stroke unit over a period of 5 years. Results: There are 7 distinctive SCA lesion patterns: (1) a lesion was found in the medial (m) branch territory of SCA (mSCA) in 14 patients; (2) a lesion in the lateral (l) branch territory of SCA (lSCA) was seen in 9 patients; (3) a coexisting lesion involving mSCA and lSCA was found in 9 patients; (4) a lesion in cortical borderzones between SCA and m/l branches of the posterior inferior cerebellar artery (PICA) was observed in 6 patients; (5) a lesion in deep borderzones between lSCA and mSCA, and lPICA and mPICA was present in 8 patients; (6) a lesion involving the medial rostral cerebellum between the right and left SCA was found in 4 patients; (7) multiple lesions involving SCA and other vertebrobasilar artery territories were present in 10 patients. The main cause was possible artery-to-artery embolism from atherosclerotic vertebrobasilar arteries to distal branches of SCA in 20 patients (33%). Fourteen patients had a source of cardioembolism (23%), and 6 patients (8%) had concomitant atherosclerotic vertebrobasilar artery disease and a source of cardioembolism. Conclusions: An acute ischemic lesion in the SCA territory is mainly multiple. The lSCA territory was the most involved area. Small territorial infarcts were frequently associated with large territorial SCA infarcts. Borderzone SCA infarcts occurred in one third of the patients with transient benign symptoms. Mass effects are unusual despite the large amount of SCA involvement. Our results supported the fact that embolism is the predominant stroke mechanism in the SCA territory infarction.
Repopulation of Apolipoprotein E Knockout Mice With CCR2-Deficient Bone Marrow Progenitor Cells Does Not Inhibit Ongoing Atherosclerotic Lesion Development
Authors: Guo Jian , de Waard Vivian , Van Eck Miranda , Hildebrand Reeni B. , van Wanrooij Eva J.A. , Kuiper Johan , Maeda Nobuyo , Benson G. Martin , Groot Pieter H.E. , Van Berkel Theo J.C.
Published: March 2005

Objective—

Using bone marrow transplantation, we have previously demonstrated the critical role that hematopoietic CCR2 plays in early atherogenesis. Reconstitution of irradiated apolipoprotein (apo) E3–Leiden mice with CCR2-deficient bone marrow progenitor cells resulted in 86% reduction on overall atherosclerotic lesion development. However, no data on CCR2 in the cause of established atherosclerosis have been reported so far.

Methods and Results—

To study the role of CCR2 in established atherosclerotic lesions, bone marrow progenitor cells harvested from apoE
−/−
and apoE
−/−
/CCR2
−/−
mice were transplanted into lethally irradiated 16-week-old apoE
−/−
mice with established atherosclerotic lesions. No significant differences were found in serum total cholesterol and triglycerides levels at different time points after transplantation. At age 16 weeks, lesion size in control apoE
−/−
mice was 3.28±1.06×10
5
μm
2
. At 9 weeks after transplantation, apoE
−/−
→ apoE
−/−
and apoE
−/−
/CCR2
−/−
→ apoE
−/−
mice had developed significantly larger atherosclerotic lesions (4.49±0.92×10
5
μm
2
,
P
<0.02 and 4.15±0.62×10
5
μm
2
,
P
<0.04 compared with controls, respectively). However, no significant effect of disruption of hematopoietic CCR2 was observed on the progression of lesions. Furthermore, the macrophage positive area (78±4% versus 72±9%) and collagen content (11±6% versus 15±3%) of the lesions were similar as well.

Conclusion—

In contrast to the critical role of CCR2 in the initiation of atherogenesis, bone marrow progenitor cell-derived CCR2 does not influence the progression of established atherosclerotic lesions, pointing to additional mechanisms for recruitment of monocytes at later stages of lesion development.