bluuebunny/crossref_metadata_2025 huggingface dataset:
First trimester threatened miscarriage treatment with human chorionic gonadotrophins: a randomised controlled trial
Authors: Qureshi N.S. , Edi‐Osagie E.C. , Ogbo V. , Ray S. , Hopkins R.E.
Published: September 2005

Objective  To determine whether administration of exogenous human chorionic gonadotrophin (hCG) treatment improve the pregnancy outcome in first trimester threatened miscarriages.

Design  A prospective, double blind, randomised, placebo‐controlled trial.

Setting  The Early Pregnancy Assessment Unit, Royal Bolton Hospital, Bolton, United Kingdom.

Population  One hundred and eighty‐three women with vaginal bleeding and a viable fetus seen on ultrasound scan (USS) in the first 12 weeks of pregnancy.

Methods  The patients were randomised to receive either hCG or placebo treatment until 14 weeks of gestation.

Main outcome measures  The primary objective of the trial was to determine the miscarriage rate in the hCG arm compared from the placebo arm.

Results  Of the 183 cases, 87 were randomised to treatment with hCG while 96 were randomised to receive a placebo. Forty‐seven (25%) did not comply with the study protocol. The mean [SD] gestational age at presentation was 7 [1.33] weeks. The mean [SD] age of women in study was 27 [5] years in the placebo and 28 [5] in the hCG group. The mean body mass index (kg/m2) was 25 [5] in the study. The number of patients actively bleeding per vaginum at presentation was 85 (93%) in placebo group and 79 (96%) in the hCG group. The median number of hCG or placebo injections for both groups was 7. Ten women (11%) in the placebo group proceeded to have a complete miscarriage, as did 10 women (12%) in the hCG group, relative risk (RR) [95% confidence interval (CI)] of 1.1 (0.63–1.6).

Conclusion  Our study showed no evidence of a difference in the outcome of threatened miscarriages when treated with hCG in the first trimester, this may be because our study sample size was small and follow up was suboptimal. A large, randomised, multicentre trial is still needed to establish the usefulness of hCG treatment in cases of threatened miscarriage.
Progress of first stage of labour for multiparous women: an observational study
Authors: Lavender Tina , Hart Anna , Walkinshaw Stephen , Campbell Elizabeth , Alfirevic Zarko
Published: September 2005

As there is no universal definition of ‘normal’ labour, diagnosing prolonged labour is inherently difficult. Simple charts (partograms) are used to aid this process; however, there are little empirical data on which to base such charts. Therefore, we monitored 403 multiparous women, in the first stage of labour with uncomplicated term pregnancies, in a midwife‐led unit. They had vaginal examinations every 2 hours, and we modelled rates of cervical dilatation for all women, either to the end of the first stage of labour or to the point of transfer for intervention. Overall, the median rate of dilatation was 1.9 cm/hour and the 5th percentile was 0.5 cm/hour. There was a weak positive correlation between initial dilatation and rate of dilatation (r= 0.2). Individualised computer‐based partograms incorporating some of the factors that affect progress might prove useful in the future.
Mode of delivery and severe stress incontinence. A cross‐sectional study among 2625 perimenopausal women
Authors: Fritel Xavier , Ringa Virginie , Varnoux Noëlle , Fauconnier Arnaud , Piault Stéphanie , Bréart Gérard
Published: September 2005

Objective  To estimate the prevalence of severe stress urinary incontinence (SUI) among perimenopausal women and to examine potential obstetric risk factors.

Design  Mail survey of female volunteers for epidemiological research.

Setting  Postal questionnaire on SUI.

Population  Three thousand one hundred and fourteen women aged 49–61 years who comprised the GAZEL cohort.

Methods  Logistic regression using data from the entire cohort to estimate the impact of risk factors. A second logistic regression using data from women who had given birth included obstetric history.

Main outcome measure  Prevalence of severe SUI defined by the response ‘often’ or ‘all the time’ to the question ‘Does urine leak when you are physically active, cough or sneeze?’

Results  Two thousand six hundred and twenty‐five women (85%) completed and returned the questionnaire The frequency of SUI reported in the preceding four weeks was as follows: ‘never’ 32%, ‘occasionally’ 28%, ‘sometimes’ 26%, ‘often’ 10% and ‘all the time’ 5%. Prevalence of severe SUI was lowest among nulliparous women (7%), but it was similar among parous women regardless of birth number (14–17%). The prevalence of severe SUI was not associated with mode of delivery (14% for women delivered by caesarean only vs 16% for vaginal births). Significant risk factors for severe SUI were high body mass index (BMI >30), diabetes mellitus, previous incontinence surgery, parity and first delivery under the age of 22 years.

Conclusion  Previous pregnancy itself is a risk factor for severe SUI among women who reach the age of 50. In this age group the impact of the mode of delivery (spontaneous, forceps or caesarean) on severe SUI is slight.
Recurrence risk in hyperemesis gravidarum
Authors: Trogstad Lill I.S. , Stoltenberg Camilla , Magnus Per , Skjærven Rolv , Irgens Lorentz M.
Published: September 2005

Objectives  To compare the risk of hyperemesis gravidarum in second pregnancies in women with and without hyperemesis in their first pregnancy, and to determine if this risk changes with changes in paternity or with the interval between deliveries.

Design  Cohort study.

Setting  Data from the population‐based Medical Birth Registry of Norway, 1967–1998.

Sample  All women in the registry with records of their first and second singleton delivery, a total of 547,238 women.

Methods  The relative risk of hyperemesis in the second delivery was estimated as odds ratios (ORs) in logistic regression models, controlling for potential confounding factors.

Main outcome measures  The main outcome measure was the risk of hyperemesis in the second pregnancy according to hyperemesis in the first pregnancy, interval between deliveries and change in paternity.

Results  The risk of hyperemesis was 15.2% in the second pregnancy in women with and 0.7% in women without previous hyperemesis [OR = 26.4, 95% confidence interval (CI) 24.2, 28.7]. The OR did not change after adjustment for maternal age, change in paternity, period of the first delivery and time interval between deliveries. After a change in paternity, the risk of recurrent hyperemesis was 10.9% compared with 16.0% in women without a change in paternity [adjusted OR (aOR) = 0.60, 95% CI 0.39, 0.92]. The risk of hyperemesis in the second pregnancy increased with increasing time interval between deliveries, but only in women with no previous hyperemesis.

Conclusions  The primary finding was the high risk of recurrence observed in women with hyperemesis in the first pregnancy. The risk was reduced by a change in paternity. For women with no previous hyperemesis, a long interval between births slightly increased the risk of hyperemesis in the second pregnancy. Further studies are needed to explore the relative impact of genetic and environmental factors and their possible interactions in hyperemesis gravidarum.
America's Palimpsest: Ground‐Zero Democracy and the Capitol Mall
Authors: Witt Matthew T.
Published: September 2005

This article examines the history of the Capitol Mall from its inception in 1791 to recent legislation prohibiting further development along the Mall's primary axes. This movement to restrict further development of the Mall's massive open spaces derives from concerns that fail to fully articulate the iconographic significance these spaces represent. Drawing from the Mall's 200‐year history of master planning, this article examines the Mall's palimpsestic and emergent qualities and presents planning criteria that make it possible to build future commemorative works within the Mall's primary open spaces while retaining the overall integrity of its grandeur.
Civic Engagement in the Twenty‐First Century: Toward a Scholarly and Practical Agenda
Authors: Cooper Terry L.
Published: September 2005

We understand civic engagement to mean people participating together for deliberation and collective action within an array of interests, institutions and networks, developing civic identity, and involving people in governance processes.
Democratizing the Administrative State: Connecting Neighborhood Councils and City Agencies
Authors: Kathi Pradeep Chandra , Cooper Terry L.
Published: September 2005

Citizen participation in government decision making, especially at the local level, has received heightened attention with regard to its promise for improved governance. The overarching administrative ethos of the administrative state creates barriers to citizen participation in governance. Developing and nurturing citizen participation in the presence of the administrative state is a significant challenge. Drawing on the literary tradition of public engagement and learning, this article models a developmental strategy of participation that offers one avenue for achieving meaningful partnerships between city agencies and neighborhood councils in a metropolitan environment. We present a model of citizen participation that brings neighborhood councils and city agencies together in a collaborative partnership. This model is based on the literature on citizen participation, which focuses on the significance of interactive processes in building trust among participants and creating mutual understanding and agreement.
Nonprofits and Civic Engagement
Authors: Berry Jeffrey M.
Published: September 2005

There are approximately 800,000 501(c)(3) nonprofits large enough to register with the federal government. Add churches, foundations, and nonprofits too small to register, and the number is far higher than that. The potential for nonprofits to engage their clients and members in community affairs and public policy making is, in theory, enormous. Yet, perversely, nonprofits are regulated by the federal government in such a way that discourages the involvement of their followers in the public policymaking process. This is a problem, not simply because we social scientists believe civic engagement is a good thing, but because these regulatory standards sharply skew public participation. Although middle‐ and upper‐class individuals have many organizations that engage and mobilize them, nonprofits usually are the only organizations that work on behalf of the poor, those without health insurance, immigrants, the disabled, and most other marginalized constituencies. Put bluntly, federal law works against the participation of the most disadvantaged in society.
The “Compleat” Policy Analyst: A Top 10 List
Authors: Lidman Russell , Sommers Paul
Published: September 2005

In this article, the authors provide a list of the top 10 ways to become a “compleat” policy analyst, drawing on lessons from their own experience as policy analysts. The authors make no claims that their list is unique. However, they suggest the items included within it are supported in the academic and practitioner‐oriented literature. Counting down from number 10—“The compleat policy analyst knows how to skip steps”—the authors present and comment on the items in turn. The authors suggest the number one concern for practitioners is “to live with uncertainty.” Other items on the list include eating crow, loving numbers, and acknowledging values and politics in the analytical process.
Is promotion of physical activity a wise use of societal resources? Issues of cost–effectiveness and equity in health
Authors: Hagberg Lars Axel , Lindholm Lars
Published: September 2005

Physical activity creates health benefits, and society makes large contributions in order to promote physical activity within the population. However, the cost–effectiveness and equity‐in‐health effect of these efforts is seldom evaluated. A model for economic evaluation of community‐promoted physical activity has been constructed based on referenced works on the health effects of physical activity, standard methods of economic evaluation, and targets for equity in health. This model was then used to assess published evaluations. A search for programs of community‐promoted physical activity aimed to promote health or prevent illness found only eight economic evaluations. Three were based on models, and five evaluated actual interventions. Almost every aspect of the model proposed in this article is included in some of the earlier studies, but several important aspects were excluded in each previous study. A cost–effectiveness analysis of community‐promoted physical activity is possible, but adequate knowledge of the components of cost–effectiveness and equity‐in‐health effect are still limited. The most important determinants of cost–effectiveness are adherence to new habits, experience and value of time spent on physical activity, and selection of the target group.
Intrinsic risk factors for inversion ankle sprains in females – a prospective study
Authors: Willems T. M. , Witvrouw E. , Delbaere K. , Philippaerts R. , De Bourdeaudhuij I. , De Clercq D.
Published: September 2005

Ankle sprains are extremely common. However, very little is known about the variables that predispose individuals to these injuries. The purpose of this study was to examine prospectively intrinsic risk factors for inversion sprains in a young physically active female population. One hundred and fifty‐nine female physical education students were evaluated for several possible intrinsic risk factors for inversion sprains at the beginning of their academic study. The evaluated intrinsic risk factors included anthropometrical and physical characteristics, ankle joint position sense, isokinetic ankle muscle strength, lower leg alignment characteristics, postural control and muscle reaction time during a sudden inversion perturbation. All sports injuries were registered during 1–3 years and exposure to sport was recorded (mean: 15.33±4.33 h a week). Thirty‐two (20%) of the 159 females sprained their ankle. The number of ankle sprains per 1000 h of sports exposure was 0.75. The Cox regression analysis revealed that females with less accurate passive joint inversion position sense [hazard ratio (HR): 1.08, 95% confidence interval (CI): 1.02–1.14 for absolute error at 15° inversion], a higher extension range of motion at the first metatarsophalangeal joint (HR: 1.03, 95% CI: 1.00–1.06) and less coordination of postural control (HR: 0.96, 95% CI: 0.93–1.00 for endpoint excursion; HR: 0.94, 95% CI: 0.89–0.99 for maximal endpoint excursion) are at greater risk of an ankle sprain. The findings of this study suggest that effective prevention and conservative rehabilitation of ankle inversion sprains should include attention to these variables.
Associations between self‐estimated and measured physical fitness among 40‐year‐old men and women
Authors: Mikkelsson L. , Kaprio J. , Kautiainen H. , Kujala U. M. , Nupponen H.
Published: September 2005

The aim was to evaluate whether 40‐year‐old men and women are able to estimate their level of fitness compared with actual measured physical fitness. Twenty‐nine men and 35 women first completed a questionnaire at home and then their physical fitness was measured at laboratory. The index of self‐estimated physical fitness was calculated by summing up the scores of self‐estimated endurance, strength, speed and flexibility. The index of self‐estimated endurance was calculated by summing up the scores of self‐estimated endurance and those of the self‐estimated distance they could run, cycle, ski and walk. The index of measured physical fitness was calculated by summing up the z‐scores of a submaximal bicycle ergometer test, ergojump tests (counter‐movement jump and jumping in 15 s), a 30‐s sit‐up test, hand‐grip tests and a sit‐and‐reach test. The correlation (Spearman) between the indices of self‐estimated and measured physical fitness was 0.54 for both sexes, and that between self‐estimated endurance and measured endurance was 0.53 for both sexes. Maximal oxygen uptake estimated based on submaximal ergometer test was higher among those with longer self‐estimated distance of running, cycling, skiing and walking (P for linear trend <0.001). Our study shows that 40‐year‐old adults can estimate at group level their fitness according to different categories moderately well. They can also estimate at group level their endurance moderately well by estimating the distance they can run, cycle, ski or walk. However, in some individuals self‐estimation of fitness is not in agreement with the results of fitness tests.
Aerobic fitness in young Norwegian men: a comparison between 1980 and 2002
Authors: Dyrstad S. M. , Aandstad A. , Hallén J.
Published: September 2005

The purpose of this study was to compare the maximal oxygen uptake (VO2max) in 18–19‐year‐old Norwegian men from 1980 to 1985 and 2002. In addition, we investigated the relationship between VO2max and education and smoking habits in the sample from 2002. From 1980 to 1985, VO2max was predicted using the Åstrand–Rhyming bicycle test for 183 610 eighteen‐year‐old Norwegian men (91% of the male Norwegian population in this age group). In 2002, the same test was performed on a representative sample of the same age population (N=1028). VO2max (mL × kg−1× min−1), decreased by 8%, body weight increased by 7% and body mass index (BMI) increased by 6% over the approximately 20‐year period (P<0.01). Results from the 2002 sample revealed that smokers had a lower VO2max than non‐smokers and vocational students had a lower VO2max than academic students (P<0.05). The average reduction in VO2max was because of an increased number of men with low or very low VO2max, and a reduced number of men with high VO2max values. This is of particular concern since the prevalence of lifestyle‐related diseases is higher in groups with low VO2max.
Physical activity in the post‐pubertal period is associated with maintenance of pre‐pubertal high bone density – a 5‐year follow‐up
Authors: Valdimarsson Ö. , Sigurdsson G. , Steingrímsdóttir L. , Karlsson M. K.
Published: September 2005

Objective: To evaluate the association between physical activity (PA) and skeletal growth in girls during adolescence.

Design: A 5‐year, observational, population‐based study (Reykjavik, Iceland).

Subjects: Seventy‐eight Caucasian girls, mean age 13.4±1.0 (mean±SD) years at baseline.

Methods: Bone mineral density (BMD, g/cm2) and bone width (cm) were measured in the forearm by single‐photon absorptiometry at baseline and with dual‐energy X‐ray absorptiometry after 3 and 5 years, when lumbar spine, femoral neck (FN) and total body were also evaluated. Half of the physically active girls were compared with the other half of less active girls.

Results: BMD in physically active girls was higher in the forearm at both baseline (P=0.001) and after 5 years (P=0.04) in comparison with less active girls. BMD was higher for the total body (P=0.0001), spine L2–L4 (P=0.02) and FN (P=0.002) in the active girls at age 18. The accrual of forearm BMD and bone width from age 13 to 18 was no different when comparing the two groups.

Conclusions: Pre‐pubertal PA is associated with high BMD at age 13 and continued PA is associated with maintenance of high BMD until age 18.
Validity and reliability of selected commercially available metabolic analyzer systems
Authors: Hodges L. D. , Brodie D. A. , Bromley P. D.
Published: September 2005

Automated metabolic gas analysis systems have advanced considerably over the past decade. They provide an abundance of information, which is not possible by using the traditional Douglas bag method and have become an essential tool in both physiological monitoring and in the diagnosis of cardiopulmonary disease. The validity and reliability of the different online metabolic analyzer systems are not well known, with relatively few independent studies being published. The purpose of this review was to examine and evaluate current literature regarding the validity and reliability of commercially available metabolic analyzer systems. This review reveals significant differences between the available systems in the way that they capture and process basic respiratory measurements. Online metabolic analyzer systems were found to vary significantly when compared with Douglas bag methods. These variations have the potential to introduce error into the accuracy with which the health of cardiovascular system can be assessed or training loads can be assigned. Compounding this is the fact that many automated systems are a “black box”, which makes it easy to generate data without the user having much understanding of how the data were generated. In conclusion automated metabolic analyser systems are a scientifically robust method for the evaluation of cardiopulmonary function. Individual researchers and clinicians must, however, be able to make their own decisions about the level of error that is tolerable for their individual needs. This presents a significant practical challenge in light of the speed with which technical developments in the field occur and we make some suggestions for the formulation of intersystem comparison studies.
Peculiarities of Host Cholesterol Transport to the Unique Intracellular Vacuole Containing Toxoplasma
Authors: Sehgal Alfica , Bettiol Silvana , Pypaert Marc , Wenk Markus R. , Kaasch Achim , Blader Ira J. , Joiner Keith A. , Coppens Isabelle
Published: September 2005

The intracellular protozoan Toxoplasma gondii is auxotrophic for low‐density lipoprotein (LDL)‐derived cholesterol (C). We previously showed that T. gondii scavenges this essential lipid from host endolysosomal compartments and that C delivery to the parasitophorous vacuole (PV) does not require transit through host Golgi or endoplasmic reticulum. In this study, we explore the itinerary of C from the host endolysosomes to the PV. Labeled C incorporated into LDL is rapidly detected in intravacuolar parasites and partially esterified by the parasites. In contrast to diverse mammalian organelles, the post‐endolysosomal transfer of C to the PV does not involve the host plasma membrane as an intermediate. Nevertheless, the PV membrane is accessible to extracellular sterol acceptors, suggesting C trafficking from intracellular parasites to host plasma membrane. C movement to the PV requires temperatures permissive for vesicular transport, metabolic energy and functional microtubules. Host caveolae vesicles and the sterol carrier protein‐2 do not participate in this process. Proteolytic treatment of purified PV or free parasites abolishes C acquisition by the parasites. Altogether, these results support a vesicular transport system from host endolysosomes to the PV, and a requirement for PV membrane and parasite plasma membrane proteins in C delivery to T. gondii.
MAGNETIC RESONANCE IMAGING FEATURES OF CERVICAL SPINAL CORD MENINGIOMAS
Authors: McDonnell John J. , Tidwell Amy S. , Faissler Dominik , Keating John
Published: September 2005

The records of four dogs with cervical spinal cord meningiomas were retrospectively reviewed. Signalment, history, laboratory findings, neurological examination, and histopathological findings were evaluated. Magnetic resonance imaging (MRI) was performed using a 1.0‐T superconducting magnet and T2‐weighted (W) and noncontrast and postcontrast T1‐W spin echo pulse sequences. Meningiomas were located at the level of the second, third, and fifth cervical vertebrae and the C2–3 intervertebral space. All meningiomas appeared as focal masses that were hyperintense to the spinal cord on T2‐W images and iso‐ to hypointense on the T1‐W images. They could be identified as intradural and extramedullary in origin based on a broad‐based dural margin seen on at least one of the imaging planes and a gradual expansion of the subarachnoid space cranial and caudal to the mass, best noted on the transverse and dorsal plane images. On dorsal plane T2‐W images in three dogs, expansion of the subarachnoid space adjacent to the mass appeared similar to the myelographic “golf tee” sign. All meningiomas exhibited moderate, well‐defined contrast enhancement with dural tails seen in three of the four dogs. One dog had extension into the intervertebral foramen along the nerve and ipsilateral atrophy of the muscles of the neck. By differentiating the meningiomas from intramedullary tumors and by clearly depicting the extent of the masses, MRI provided valuable information about treatment options and prognosis.
ULTRASONOGRAPHIC FEATURES OF PERITONEAL CESTODIASIS CAUSED BYMESOCESTOIDESSP. IN A DOG AND IN A CAT
Authors: Venco Luigi , Kramer Laura , Pagliaro Luigi , Genchi Claudio
Published: September 2005

Peritoneal infections caused byMesocestoidesspp. are rare in dogs and cats. Little data exist on the role of abdominal ultrasonography for diagnosis and therapy management of the disease. We describe the ultrasonographic features of peritoneal cestodiasis in a dog and in a cat. In the dog, abdominal ultrasound allowed both a presumptive diagnosis and the collection of tissue samples to confirm peritoneal larval infection. Ultrasound was also very useful for therapy management. In the second patient the ultrasonographic features of tetrathyridial infection in a cat in which the parasite was observed as an incidental finding during ovariohysterectomy are described.
ULTRASONOGRAPHIC FEATURES OF GRASS AWN MIGRATION IN THE DOG
Authors: Gnudi Giacomo , Volta Antonella , Bonazzi Mattia , Gazzola Margherita , Bertoni Giorgio
Published: September 2005

The aim of this study was to describe the ultrasonographic features of grass awns in soft tissue. A 10 MHz linear transducer was used. Ultrasound images from 25 dogs (27 awns) were collected and compared with the results from water bath studies using wild oat seeds (Avena spp.) collected in the field. Wild oat seeds were the most common grass awn found in soft tissue of dogs. Ultrasonographically grass awns appeared as a double/triple spindle‐shaped echogenic interface within soft tissue. The same appearance was observed in water bath studies. In four dogs, the grass awn was removed surgically with a clamp introduced into a fistulous tract, using sonographic guidance. The grass awn was not found surgically in only three dogs, suggesting more attention during surgery. Ultrasonography is a useful diagnostic imaging technique to identify grass awns within soft tissue.
Abnormal Tribological Behavior of Multiwalled Nanotube Rafts Part I: Aligned Rafts
Authors: Yang Wei , Wang Hongtao , Huang Y.
Published: September 2005

When two material surfaces are brought into contact, the classical Amonton’s law predicts a monotonically increasing relation between the frictional force and the normal pressure. An abnormal friction law refers to the case where the friction force declines as the normal pressure increases. We investigate the possibility of abnormal tribological behavior for two surfaces coated with aligned multiwalled nanotube rafts. Part I of the investigation is devoted to the case when two contacting nanotube rafts are aligned to each other, while part II is aimed at more general case of arbitrarily oriented nanotube rafts. The analysis in part I is based on the JKR theory of adhesion and linear elasticity for aligned multiwalled carbon nanotube raft configuration. It gives rise of several interesting predictions. First, two surfaces covered by aligned nanotubes can adhere when bringing into a pressureless contact. Second, the aligned multiwalled nanotube rafts exhibit a detachment work that declines with the contacting pressure. Third, in contrast to the Amonton’s law, the frictional force would decline as the normal pressure increases.
A Self-Consistent Model for the Inelastic Deformation of
Nanocrystalline Materials
Authors: Capolungo L. , Cherkaoui M. , Qu J.
Published: September 2005

A self-consistent scheme is used to describe the behavior of nanocrystalline F.C.C. materials. The material is approximated as a composite with two phases. The inclusion phase represents the grain cores while the matrix phase represents both grain boundaries and triple junctions. The dislocation glide mechanism is incorporated in the constitutive law of the inclusion phase while a thermally activated mechanism accounting for the penetration of dislocations in the grain boundaries is incorporated in the constitutive law of the matrix phase. The model is applied to pure Cu and the results are compared with various experimental data.
Nonlocality Effect in Atomic Force Microscopy Measurement and Its Reduction by an Approaching Method
Authors: Hu Ming , Wang Haiying , Xia Mengfen , Ke Fujiu , Bai Yilong
Published: September 2005

In AFM measurements of surface morphology, the locality is a traditional assumption, i.e., the load recorded by AFM is simply the function of the distance between the tip of AFM and the point on a sample right opposite the tip [Giessibl, F. J., 2003, “Advances in Atomic Force Microscopy,” Rev. Mod. Phys., 75, pp. 949–983]. This paper presents that nonlocality effect may play an important role in atomic force microscopic (AFM) measurement. The nonlocality of AFM measurement results from two different finite scales: the finite scale of the characteristic intermolecular interaction distance and the geometric size of AFM tip. With a coupled molecular-continuum method, we analyzed this nonlocality effect in detail. It is found that the nonlocality effect can be formulated by a few dimensionless parameters characterizing the ratio of the following scales: the characteristic intermolecular interaction distance between the AFM tip and the sample, the characteristic size of the tip and the characteristic nano-structure and∕or the nanoscale roughness on the surface of a sample. The present work also suggests a data processing algorithm—the approaching method, which can reduce the nonlocality effect in AFM measurement of surface morphology effectively.
Structure and Properties of Electrocodeposited Cu-Al2O3 Nanocomposite Thin Films
Authors: Gan Yong , Lee Dongyun , Chen Xi , Kysar Jeffrey W.
Published: September 2005

Nanocomposite thin films which consist of 50nmAl2O3 nanoparticles in a copper metal matrix were deposited on a silicon wafer. The thickness of the nanocomposite thin films was about 3microns and the volume density of the nanoparticles was between 3% and 5%. The films were synthesized using electrocodeposition. The grain size of the nanocomposite film was significantly smaller than the grain size of control films of pure copper. Electron backscatter diffraction (EBSD) experiments indicate that neither the nanocomposite thin films nor the control films exhibits a crystallographic texture. Nanoindentation experiments show that the hardness of the nanocomposite thin film is approximately 25% higher than the hardness of the control films of pure copper. A prototype of a microchannel array in the nanocomposite thin film was made using standard microelectromechanical (MEMS) fabrication technology. It is expected that the enhanced mechanical properties exhibited by nanocomposite thin films have the potential to improve the reliability of various MEMS devices which rely on thin metal films. The results presented herein lay the groundwork for future studies in which the size, volume density, morphology, distribution as well as type of nanoparticle in the nanocomposite will be systematically and independently varied in order to optimize mechanical properties.
A Finite-Temperature Continuum Theory Based on Interatomic Potentials
Authors: Jiang H. , Huang Y. , Hwang K. C.
Published: September 2005

There are significant efforts to develop continuum theories based on atomistic models. These atomistic-based continuum theories are limited to zero temperature (T=0K). We have developed a finite-temperature continuum theory based on interatomic potentials. The effect of finite temperature is accounted for via the local harmonic approximation, which relates the entropy to the vibration frequencies of the system, and the latter are determined from the interatomic potential. The focus of this theory is to establish the continuum constitutive model in terms of the interatomic potential and temperature. We have studied the temperature dependence of specific heat and coefficient of thermal expansion of graphene and diamond, and have found good agreements with the experimental data without any parameter fitting. We have also studied the temperature dependence of Young’s modulus and bifurcation strain of single-wall carbon nanotubes.
Analysis and Testing of Mixed-Mode Interlaminar Fracture Behavior of Glass-Cloth∕Epoxy Laminates at Cryogenic Temperatures
Authors: Shindo Yasuhide , Shinohe Daiki , Kumagai Susumu , Horiguchi Katsumi
Published: September 2005

This paper presents results from an analytical and experimental study of the effect of temperature and mixed-mode ratio on the interlaminar fracture toughness in glass-cloth∕epoxy laminates. Mode I, mode II, and mixed-mode tests were conducted by the double-cantilever beam, end-notched flexure, and mixed-mode bending test methods at room temperature, liquid nitrogen temperature (77 K), and liquid helium temperature (4 K). A finite element model was used to perform the delamination crack analysis. Mode I, mode II, and mixed-mode energy release rates at the onset of delamination crack propagation were computed using the virtual crack closure technique. The fracture surfaces were examined by scanning electron microscopy to correlate with the interlaminar fracture properties.
Atomistic Determination of Continuum Mechanical Properties of Ion-Bombarded Silicon
Authors: Kalyanasundaram N. , Freund J. B. , Johnson H. T.
Published: September 2005

Highly disordered, ion-processed silicon is studied using a molecular dynamics simulation with empirical interatomic potentials. The surface free energy density, stress-strain relations, and continuum surface features of silicon, bombarded in the simulations to relatively high fluence by medium energy argon ions, are computed statistically by preparing multiple randomized ion-bombarded specimens. The surface-free energy per unit area for the ion-bombarded silicon is about 1.76J∕m2, much lower than the 2.35J∕m2 corresponding to a (001) unrelaxed, crystalline silicon surface. A stress-strain curve is obtained computationally by performing a constant strain test on the ion-bombarded specimens and by calculating stresses from the interatomic forces acting across different cross sections in the sample. The resulting tensile elastic modulus of the material, while slightly elevated due to the prominence of the free surface in the thin layer, is in good agreement with available experimental data. The surface is characterized using an interatomic potential-based C2 continuous sampling method.
Bacterial Immunity Traded for Sperm Viability in Male Crickets
Authors: Simmons Leigh W. , Roberts Benjamin
Published: September 2005

The notion that a trade-off exists between immunity and reproduction is now a central concept in theories of sexual selection. However, whether such a trade-off exists between immunity and gamete viability has not been established. Here we show that genetic variance for high levels of an immune response required to fight bacterial infections is associated with genetic variance for low sperm viability. These data have implications for our understanding of sexual selection mechanisms and of reproductive costs in male longevity.
Structural Phylogenetics and the Reconstruction of Ancient Language History
Authors: Dunn Michael , Terrill Angela , Reesink Ger , Foley Robert A. , Levinson Stephen C.
Published: September 2005

The contribution of language history to the study of the early dispersals of modern humans throughout the Old World has been limited by the shallow time depth (about 8000 ± 2000 years) of current linguistic methods. Here it is shown that the application of biological cladistic methods, not to vocabulary (as has been previously tried) but to language structure (sound systems and grammar), may extend the time depths at which language data can be used. The method was tested against well-understood families of Oceanic Austronesian languages, then applied to the Papuan languages of Island Melanesia, a group of hitherto unrelatable isolates. Papuan languages show an archipelago-based phylogenetic signal that is consistent with the current geographical distribution of languages. The most plausible hypothesis to explain this result is the divergence of the Papuan languages from a common ancestral stock, as part of late Pleistocene dispersals.
Direct Observation of the Three-State Folding of a Single Protein Molecule
Authors: Cecconi Ciro , Shank Elizabeth A. , Bustamante Carlos , Marqusee Susan
Published: September 2005

We used force-measuring optical tweezers to induce complete mechanical unfolding and refolding of individual
Escherichia coli
ribonuclease H (RNase H) molecules. The protein unfolds in a two-state manner and refolds through an intermediate that correlates with the transient molten globule–like intermediate observed in bulk studies. This intermediate displays unusual mechanical compliance and unfolds at substantially lower forces than the native state. In a narrow range of forces, the molecule hops between the unfolded and intermediate states in real time. Occasionally, hopping was observed to stop as the molecule crossed the folding barrier directly from the intermediate, demonstrating that the intermediate is on-pathway. These studies allow us to map the energy landscape of RNase H.
Picturing Particle Processes
Authors: Kane Gordon
Published: September 2005

Drawing Theories Apart
. The Dispersion of Feynman Diagrams in Postwar Physics.
By David Kaiser
. University of Chicago Press, Chicago, 2005. 489 pp. $80, £56. ISBN 0-226-42266-6. Paper, $30, £21. ISBN 0-226-42267-4.

Writing for historians of science and physicists, the author explores how physicists used and adapted Feynman diagrams as well as how the diagrams influenced their research.
Journey into the Unknown Beyond
Authors: Fisk Len A.
Published: September 2005

The Voyager 1 spacecraft has passed an important milestone. As is reported in papers in this issue, Voyager 1 has crossed the termination shock of the solar wind, where the wind abruptly decelerates to begin its merger into the local interstellar medium. The termination shock provided surprises; the region beyond is truly uncharted territory.
CURRENT TRENDS IN QUARANTINE ENTOMOLOGY
Authors: Follett Peter A. , Neven Lisa G.
Published: September 2005

▪ Abstract  With world trade in agricultural commodities increasing, the introduction of exotic insects into new areas where they become pests will increase. The development and application of quarantine treatments or other mitigation approaches to prevent pest introduction in traded commodities raise many research and regulatory issues. The probit 9 standard for quarantine treatment efficacy has given way to risk-based alternatives. Varietal testing may have merit for some treatments or commodities but not for others. Development of generic treatments to control broad groups of insects or insects in all commodities can expedite new trade in agricultural products. Area-wide pest management programs lower pest levels before harvest and improve the quarantine security provided by any postharvest treatments. Systems approaches capitalize on cumulative pest mortality from multiple control components to achieve quarantine security in an exported commodity. Certain quarantine treatment technologies such as irradiation are not universally accepted, which is slowing their adoption. Standardized phytosanitary measures and research protocols are needed to improve the flow of information when countries propose to trade in a regulated commodity.
SIGNALING FOR CONTRACTION AND RELAXATION IN SMOOTH MUSCLE OF THE GUT
Authors: Murthy Karnam S.
Published: September 2005

▪ Abstract  Phosphorylation of Ser19on the 20-kDa regulatory light chain of myosin II (MLC20) by Ca2+/calmodulin-dependent myosin light-chain kinase (MLCK) is essential for initiation of smooth muscle contraction. The initial [Ca2+]itransient is rapidly dissipated and MLCK inactivated, whereas MLC20and muscle contraction are well maintained. Sustained contraction does not reflect Ca2+sensitization because complete inhibition of MLC phosphatase activity in the absence of Ca2+induces smooth muscle contraction. This contraction is suppressed by staurosporine, implying participation of a Ca2+-independent MLCK. Thus, sustained contraction, as with agonist-induced contraction at experimentally fixed Ca2+concentrations, involves (a) G protein activation, (b) regulated inhibition of MLC phosphatase, and (c) MLC20phosphorylation via a Ca2+-independent MLCK. The pathways that lead to inhibition of MLC phosphatase by Gq/13-coupled receptors are initiated by sequential activation of Gαq/α13, RhoGEF, and RhoA, and involve Rho kinase–mediated phosphorylation of the regulatory subunit of MLC phosphatase (MYPT1) and/or PKC-mediated phosphorylation of CPI-17, an endogenous inhibitor of MLC phosphatase. Sustained MLC20phosphorylation is probably induced by the Ca2+-independent MLCK, ZIP kinase. The pathways initiated by Gi-coupled receptors involve sequential activation of Gβγi, PI 3-kinase, and the Ca2+-independent MLCK, integrin-linked kinase. The last phosphorylates MLC20directly and inhibits MLC phosphatase by phosphorylating CPI-17. PKA and PKG, which mediate relaxation, act upstream to desensitize the receptors (VPAC2and NPR-C), inhibit adenylyl and guanylyl cyclase activities, and stimulate cAMP-specific PDE3 and PDE4 and cGMP-specific PDE5 activities. These kinases also act downstream to inhibit (a) initial contraction by inhibiting Ca2+mobilization and (b) sustained contraction by inhibiting RhoA and targets downstream of RhoA. This increases MLC phosphatase activity and induces MLC20dephosphorylation and muscle relaxation.
Transcriptional and posttranscriptional regulation of angiopoietin-2 expression mediated by IGF and PDGF in vascular smooth muscle cells
Authors: Phelps Eric D. , Updike Dawn L. , Bullen Elizabeth C. , Grammas Paula , Howard Eric W.
Published: September 2005

Angiopoietins play a significant role in vascular development and angiogenesis. Both angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2) bind the receptor tyrosine kinase Tie2. However, while Ang1 signaling results in the stabilization of vessel structure, Ang2 has been linked to vascular instability. The ratio of these two Tie2 ligands is thus critical for vascular stability and remodeling. This study identifies a mechanism of growth factor-mediated reduction in Ang2 expression in vascular smooth muscle cells (VSMCs). In response to PDGF, VSMCs downregulated Ang2 mRNA levels by 75% within 4 h, with a subsequent decrease in Ang2 protein levels. Quantitation of endogenous transcription rates revealed that PDGF stimulation did not alter Ang2 transcription rates, but instead induced a posttranscriptional mechanism of rapid Ang2 mRNA destabilization. The Ang2 mRNA half-life was reduced by at least 50% after PDGF treatment. The PDGF-induced mRNA turnover mechanism was dependent on several MAPK pathways, including ERK and JNK. In contrast, IGF-I, which did not significantly activate ERK or JNK, stimulated increased Ang2 expression through transcriptional activation. These findings demonstrate that VSMCs adjust Ang2 expression through multiple mechanisms, including changes in transcription as well as posttranscriptional mRNA destabilization.
Electrophoretic and functional identification of two troponin C isoforms in toad skeletal muscle fibers
Authors: O'Connell Brett , Blazev Ronnie , Stephenson Gabriela M. M.
Published: September 2005

The differential sensitivity of frog twitch and slow-tonic fibers to Ca2+ and Sr2+ suggests that these two fiber types express different troponin C (TnC) isoforms. To date, only one TnC isoform from anurans (resembling the mammalian fast-twitch isoform) has been isolated and characterized. In this study, we examined the possibility that anuran striated muscle contains more than one TnC isoform. Toward this end, we determined the TnC isoform composition of 198 single fibers from the rectus abdominis of the cane toad (a mixed slow-tonic and twitch muscle) and of toad cardiac muscle using a method that enables the identification of TnC isoforms on the basis of the effect of Ca2+ on their electrophoretic mobility. The fibers were typed according to their myosin heavy chain (MHC) isoform composition. The data indicate that striated muscle of the cane toad contains two TnC isoforms, one of which (TnC-t) is present in all fibers displaying only twitch MHC isoforms and the other of which (TnC-T/c) is present in fibers displaying the tonic MHC isoform and in cardiac muscle. For a subpopulation of 15 fibers, the TnC isoform composition was also compared with Ca2+ and Sr2+ activation characteristics. Fibers containing the TnC-T/c isoform were ∼3-fold more sensitive to Ca2+, ∼40-fold more sensitive to Sr2+, and responded to a ∼4.6-fold broader range of [Ca2+] than did fibers containing the TnC-t isoform. The Ca2+ activation properties of toad fibers containing the TnC-T/c isoform appear to be consistent with the previously reported physiological characteristics of amphibian slow-tonic muscle fibers.
Activity rhythm of golden hamster (Mesocricetus auratus) can be entrained to a 19-h light-dark cycle
Authors: Chiesa Juan J. , Anglès-Pujolràs Montserrat , Díez-Noguera Antoni , Cambras Trinitat
Published: September 2005

Both temporary access to a running wheel and temporary exposure to light systematically influence the phase producing entrainment of the circadian activity rhythm in the golden hamster ( Mesocricetus auratus). However, precise determination of entrainment limits remains methodologically difficult, because such calculations may be influenced by varying experimental paradigms. In this study, effects on the entrainment of the activity pattern during successive light-dark (LD) cycles of stepwise decreasing periods, as well as wheel running activity, were investigated. In particular, the hamster activity rhythm under LD cycles with a period (T) shorter than 22 h was studied, i.e., when the LD cycle itself had been shown to be an insufficiently strong zeitgeber to synchronize activity rhythms. Indeed, it was confirmed that animals without a wheel do not entrain under 11:11-h LD cycles (T = 22 h). Subsequently providing hamsters continuous access to a running wheel established entrainment to T = 22 h. Moreover, this paradigm underwent further reductions of the T period to T = 19.6 h without loss of entrainment. Furthermore, restricting access to the wheel did not result in loss of entrainment, while even entrainment to T = 19 h was observed. To explain this observed shift in the lower entrainment limit, our speculation centers on changes in pacemaker response facilitated by stepwise changes of T spaced very far apart, thus allowing time for adaptation.