bluuebunny/crossref_metadata_2025_split huggingface dataset:
Z‐scores of the fetal aortic isthmus and duct: an aid to assessing arch hypoplasia
Authors: Pasquini L. , Mellander M. , Seale A. , Matsui H. , Roughton M. , Ho S. Y. , Gardiner H. M. 
Published: May 2007

AbstractObjectivePrenatal diagnosis of isolated coarctation of the aorta suffers from high false positive and false negative rates. The aim of our study was to develop Z‐scores for the aortic isthmus in normal fetuses as a reference for fetuses with suspected coarctation.MethodsThe aortic isthmal diameter, immediately proximal to the insertion of the arterial duct, was measured prospectively in the transverse (three vessel and trachea) and sagittal views in 221 normal fetuses at 18 to 37 weeks' gestation. The ductal diameter was measured immediately before it entered the descending aorta in the same view. All measurements were repeated three times by a single investigator and averaged. A second investigator re‐measured the images of 50 cases to assess interobserver variability. Z‐scores were created relating isthmal and ductal diameters to femur length and gestational age. The ratio between the isthmal and ductal diameters was calculated.ResultsThe formula used to calculate Z‐scores for the three diameters was: [ln(measured isthmal diameter) − (m ln(femur length or gestational age) + c)]/root MSE, where c is the intercept, m is a multiplier and MSE is the mean squared error. The ratio between isthmal and ductal diameters was close to a constant value of 1 (95% CI 0.97–1.01), regardless of the value of femur length or gestational age.ConclusionWe have defined Z‐scores for the fetal aortic isthmus and arterial duct measured in the three vessels and trachea view and for the isthmus in the sagittal plane. In suspected coarctation, these Z‐scores and the isthmal to ductal ratio may help in longitudinal assessment of the aortic arch and aid in the prenatal diagnosis of coarctation. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Fetal thymus size as a predictor of chorioamnionitis in women with preterm premature rupture of membranes
Authors: Yinon Y. , Zalel Y. , Weisz B. , Mazaki‐Tovi S. , Sivan E. , Schiff E. , Achiron R. 
Published: April 2007

AbstractObjectiveEmerging evidence indicates that chorioamnionitis is associated with a significant decrease in thymic size at birth in very low birth weight (VLBW) preterm infants. The aim of this study was to determine whether decreased fetal thymus size is associated with histological or clinical chorioamnionitis in patients with preterm premature rupture of membranes (PROM).MethodsTwenty‐one patients between 24 and 35 weeks of gestation with preterm PROM were included. Serial ultrasound examinations were performed during the latency period, and measurements of the fetal thymus size were obtained. Small thymus was defined as a thymus perimeter ≤ 5th percentile according to a fetal thymus nomogram, which was based on measurements of 403 fetuses. Diagnosis of chorioamnionitis was made using neonatal clinical parameters and histological examinations of the placentas.ResultsIn our study 13 patients presented with thymus size below the 5th percentile. Among the 13 patients with small thymus, nine (69%) had clinical or histological findings consistent with the diagnosis of chorioamnionitis. All eight women with a normal‐sized thymus had no evidence of clinical or histological chorioamnionitis. Fetal thymus perimeter ≤ 5th percentile yielded a sensitivity of 100%, specificity of 66.7%, a positive predictive value of 69% and a negative predictive value of 100% for identifying chorioamnionitis in patients with preterm PROM.ConclusionsFetal thymus size is decreased in women with preterm PROM and chorioamnionitis. Measurement of the fetal thymus might allow an early diagnosis of chorioamnionitis in cases of preterm PROM. Normal thymus size might be used to rule out latent intrauterine infection. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Ultrasound assessment of pelvic organ prolapse: the relationship between prolapse severity and symptoms
Authors: Dietz H. P. , Lekskulchai O. 
Published: April 2007

AbstractObjectiveAt present little information is available to help define whether a certain degree of pelvic organ prolapse is clinically relevant. We performed a retrospective study to define cut‐offs for significant pelvic organ descent on the basis of prolapse symptoms.MethodsAt a tertiary urogynecological center, 735 women with symptoms of lower urinary tract dysfunction and prolapse were seen for interview, clinical examination, multi‐channel urodynamics and ultrasound imaging, while supine and after voiding, for prolapse quantification. Women with multi‐compartment prolapse, i.e. those in whom no compartment was clearly dominant were excluded. Receiver–operator statistics were used to test pelvic organ descent as a predictor of prolapse symptoms.ResultsMean age was 55.1 years, mean parity 2.8 (range, 0–12). Symptoms of prolapse were reported by 188 women (25.6%). Seventy‐four showed a symptomatic multi‐compartment prolapse and were excluded, 56 symptomatic women had cystoceles and 48 had rectoceles. Symptomatic cystoceles descended on average to 23.8 mm below the symphysis pubis and symptomatic rectoceles to 21.4 mm below the symphysis pubis. Descent was strongly associated with symptoms of prolapse (both, P < 0.001). Receiver–operating characteristics (ROC) statistics suggested a cut‐off of 10 mm below the symphysis pubis for cystocele, and 15 mm below the symphysis pubis for rectocele. ROC curves were similar for both compartments (area under the curve, 0.857 and 0.821, respectively).ConclusionsDescent of the bladder to ≥ 10 mm and of the rectum to ≥ 15 mm below the symphysis pubis are strongly associated with symptoms, and these values are proposed as cut‐offs for the diagnosis of significant prolapse on the basis of ROC statistics. Copyright © 2007 ISUOG. Published by John Wiley & Sons, Ltd.
Observations on the Use of Seprafilm® on the Brachial Plexus in 249 Operations for Neurogenic Thoracic Outlet Syndrome
Authors: Sanders Richard J. , Hammond Sharon L. , Rao Neal M. 
Published: May 2007

Purpose Seprafilm® was initially used successfully as a membrane to reduce abdominal adhesions. Subsequently it was tried in a number of other areas to reduce postoperative scarring. Seprafilm® was employed in this study to see if it would reduce postoperative scarring after supraclavicular thoracic outlet decompression for neurogenic thoracic outlet syndrome (NTOS). Material and methods There were 249 operations for primary NTOS (185) and recurrent NTOS (64). Seprafilm® was applied to the nerve roots at the end of each procedure. Diagnosis was established by careful history and extensive physical exam consisting of several provocative maneuvers. Scalene muscle block confirmed the diagnosis. Results Success rates for primary operations, 1–2 years postoperation were 74% for scalenectomy without first rib resection and 70% for scalenectomy with first rib resection. For reoperations, success rate for scalenectomy and neurolysis after transaxillary rib resection was 78% whereas success rate for neurolysis after supraclavicular scalenectomy was 68%. Seprafilm® did not significantly improve overall results compared to our results 15 years ago, although in reoperations there was a trend toward improvement with Seprafilm®. Observations in 10 reoperations after use of Seprafilm® revealed that there were fewer adhesions between fat pad and nerve roots, making it much easier to find the nerve roots. Recurrence was because of scar formation around individual nerve roots. Conclusion Seprafilm® made reoperations easier by reducing scarring between scalene fat pad and brachial plexus. However, it did not prevent scar tissue forming around the individual nerve roots nor did it significantly lower the failure rate for primary operations. The trend supported the use of Seprafilm® in reoperations.
Digesta transit in different segments of the gastrointestinal tract of pigs as affected by insoluble fibre supplied by wheat bran
Authors: Wilfart Aurélie , Montagne Lucile , Simmins Howard , Noblet Jean , Milgen Jaap van 
Published: April 2007

Digestibility is the result of two competing processes: digestion and digesta transit. To develop or parameterise mechanistic models of digestion, both processes have to be quantified. The aim of this study was to determine the effect of insoluble dietary fibre on the transit in the gastrointestinal tract of pigs. Six barrows (33 kg initial body weight and fitted with two simple T-cannulas at the proximal duodenum and distal ileum) were used in a double 3 × 3 Latin square design. Pigs were offered diets differing in total dietary fibre content (170, 220 and 270 g/kg DM) at 4 h intervals. A single meal marked with YbO2and Cr-EDTA was used to determine the kinetics of markers concentrations of the solid and liquid phases, respectively. The mean retention time (MRT), calculated by the method of the moments, averaged 1, 4 and 38 h in the stomach, small intestine and large intestine, respectively. Increasing the insoluble fibre content in the diet had no effect on MRT in the stomach and decreased the MRT of both phases in the small intestine (P < 0·05). In the large intestine, increasing the insoluble fibre content decreased the MRT of the liquid phase (P = 0·02) and tended to decrease the MRT of the solid phase (P = 0·06). Transit of the solid phase in the large intestine was 4–8 h slower than transit of the liquid phase. Analysis of marker excretion curves indicated that the small and large intestine should be represented mathematically to have both a tubular (propulsion) and compartmental (mixing) structure.
The Labour Process in the Bombay Handloom Industry, 1880–1940
Authors: HAYNES DOUGLAS E. 
Published: May 2007

AbstractAnalyses of capital-labour relations in Indian industry during the colonial period have generally been confined to studies of large-scale units. This essay turns to an examination of the organization of the workplace among handloom producers in the Bombay Presidency during the period between 1880 and 1940. While recognizing the importance of contradictions between weaving families and various kinds of capitalists, the essay eschews any straightforward model of “proletarianization” to characterize this relationship. Weavers possessed methods of resistance, particularly “everyday” actions, which thwarted efforts to impose tight regimes of labour discipline within the workshop. Seeking to contain these resistances, shahukars (putting-out merchants) and karkhandars (owners of establishments using wage labour) developed complex social relationships with their workers based upon patronage, debt, and caste. Consequently, collective protest in the industry was limited, and when it did emerge in Sholapur during the later 1930s, it was highly conditioned and constrained by the multiple lines of affiliation weavers had with karkhandars.
The anthelmintic efficacy of plant-derived cysteine proteinases against the rodent gastrointestinal nematode,Heligmosomoides polygyrus,in vivo
Authors: STEPEK G. , LOWE A. E. , BUTTLE D. J. , DUCE I. R. , BEHNKE J. M. 
Published: May 2007

SUMMARYGastrointestinal (GI) nematodes are important disease-causing organisms, controlled primarily through treatment with synthetic drugs, but the efficacy of these drugs has declined due to widespread resistance, and hence new drugs, with different modes of action, are required. Some medicinal plants, used traditionally for the treatment of worm infections, contain cysteine proteinases known to damage worms irreversiblyin vitro. Here we (i) confirm that papaya latex has marked efficacyin vivoagainst the rodent gastrointestinal nematode,Heligmosomoides polygyrus, (ii) demonstrate the dose-dependent nature of the activity (>90% reduction in egg output and 80% reduction in worm burden at the highest active enzyme concentration of 133 nmol), (iii) establish unequivocally that it is the cysteine proteinases that are the active principlesin vivo(complete inhibition of enzyme activity when pre-incubated with the cysteine proteinase-specific inhibitor, E-64) and (iv) show that activity is confined to worms that are in the intestinal lumen. The mechanism of action was distinct from all current synthetic anthelmintics, and was the same as thatin vitro, with the enzymes attacking and digesting the protective cuticle. Treatment had no detectable side-effects on immune cell numbers in the mucosa (there was no difference in the numbers of mast cells and goblet cells between the treated groups) and mucosal architecture (length of intestinal villi). Only the infected and untreated mice had much shorter villi than the other 3 groups, which was a consequence of infection and not treatment. Plant-derived cysteine proteinases are therefore prime candidates for development as novel drugs for the treatment of GI nematode infections.
Dynamical systems: stability and simulability
Authors: HOYRUP MATHIEU 
Published: May 2007

Computers are used extensively to simulate continuous dynamical systems. However, different conceptual and mathematical structures underlie discrete machines and continuous dynamics, so the question arises as to the ability of the computer to simulate or, more generally, to check the properties of a continuous system.We discuss and compare two notions of stability for a continuous dynamical system,viz.shadowing and robustness, and relate them to both the practical and theoretical computability of the system. We first discuss what we can learn from the stability of a system, using a finite-precision machine. We then show, following the work in Collins (2005), that shadowing fails but robustness succeeds in ensuring the checkability of a reachability property.
A comparison of the programme coverage of two therapeutic feeding interventions implemented in neighbouring districts of Malawi
Authors: Sadler Kate , Myatt Mark , Feleke Teshome , Collins Steve 
Published: April 2007

AbstractObjectiveTo compare therapeutic feeding programme coverage for severely malnourished children achieved by a community-based therapeutic care (CTC) programme and a therapeutic feeding centre (TFC) programme operating in neighbouring districts in Malawi.DesignTwo surveys were implemented simultaneously one in each of the two programme areas. Each survey used a stratified design with strata defined using the centric systematic area sample method. Thirty 100 km2quadrats were sampled. The community or communities located closest to the centre of each quadrat were sampled using a case-finding approach. Cases were defined as children aged under 5 years with ≤ 70% of the weight-for-height median or bilateral pitting oedema. Receipt of treatment was ascertained by the child's presence in a therapeutic feeding programme or by documentary evidence. Coverage in each quadrat was estimated in two ways, a period estimate that provides an estimation of coverage for the recent period preceding the survey and a point estimate that provides an estimation of coverage at the exact point in time of the survey.ResultsOverall the period coverage was 24.55% (95% confidence interval (CI) = 17.8–31.4%) in the TFC programme and 73.64% (95% CI = 66.0–81.3%) in the CTC programme. The point coverage was 20.04% (95% CI = 13.8–26.3%) in the TFC programme and 59.95% (95% CI = 51.4–68.5%) in the CTC programme.ConclusionsIn this context, CTC gave substantially higher programme coverage than a TFC programme. Given effective treatment, this enabled higher impact of CTC on severe malnutrition in this population.
Migration of comets to the terrestrial planets
Authors: Ipatov Sergei I. , Mather John C. 
Published: May 2007

AbstractWe studied the orbital evolution of objects with initial orbits close to those of Jupiter-family comets (JFCs), Halley-type comets (HTCs), and long-period comets, and the probabilities of their collisions with the planets. In our runs the probability of a collision of one object with the Earth could be greater than the sum of probabilities for thousands of other objects. Even without the contribution of such a few objects, the probability of a collision of a former JFC with the Earth during the dynamical lifetime of the comet was greater than 4×10−6. This probability is enough for delivery of all the water to Earth's oceans during the formation of the giant planets. The ratios of probabilities of collisions of JFCs and HTCs with Venus and Mars to the mass of the planet usually were not smaller than that with Earth. Among 30,000 considered objects with initial orbits close to those of JFCs, a few objects got Earth-crossing orbits with semimajor axesa<2 AU and aphelion distancesQ<4.2 AU, or even got inner-Earth (Q<0.983 AU), Aten, or typical asteroidal orbits, and moved in such orbits for more than 1 Myr (up to tens or even hundreds of Myr). From a dynamical point of view, the fraction of extinct comets among near-Earth objects can exceed several tens of percent, but, probably, many extinct comets disintegrated into mini-comets and dust during a smaller part of their dynamical lifetimes.
Is the near-Earth asteroid 2000 PG3 an extinct comet?
Authors: Babadzhanov Pulat B. , Williams Iwan P. 
Published: May 2007

AbstractThe existence of an observed meteor shower associated with some Near-Earth Asteroid (NEA) is one of the few useful criteria that can be used to indicate that such an object could be a candidate for being regarded as an extinct or dormant cometary nucleus. In order to identify possible new NEA-meteor showers associations, the secular variations of the orbital elements of the NEA 2000 PG3, with comet-like albedo (0.02), and moving on a comet-like orbit, was investigated under the gravitational action of the Sun and six planets (Mercury to Saturn) over one cycle of variation of the argument of perihelion. The theoretical geocentric radiants and velocities of four possible meteor showers associated with this object are determined. Using published data, the theoretically predicted showers were identified with the night-time September Northern and Southern δ-Piscids fireball showers and several fireballs, and with the day-time meteor associations γ-Arietids and α-Piscids. The character of the orbit and low albedo of 2000 PG3, and the existence of observed meteor showers associated with 2000 PG3 provide evidence supporting the conjecture that this object may be of cometary nature.
Inverse problems of NEO photometry: Imaging the NEO population
Authors: Kaasalainen1 Mikko , Ďurech Josef 
Published: May 2007

AbstractThe physical properties of NEOs and other asteroids are mostly obtained with photometry. The resulting models describe the shapes, spin states, scattering properties and surface structure of the targets, and are the solutions of inverse problems involving comprehensive mathematical analysis. We review what can and cannot be obtained from photometric (and complementary) data, and how all this is done in practice. The role of photometry will become completely dominating with the advent of large-scale surveys capable of producing calibrated brightness data. Due to their quickly changing geometries with respect to the Earth, NEOs are the population that can be mapped the fastest.
Tidal disturbances of small cohesionless bodies: limits on planetary close approach distances
Authors: Michel Patrick , Holsapple K. A. 
Published: May 2007

AbstractThe population of Near-Earth Objects contains small bodies that can make very close passages to the Earth and the other planets. Depending on the approach distance and the object's internal structure, some shape readjustment or disruption may occur as a result of tidal forces. A real example is the comet Shoemaker Levy 9 which disrupted into 21 fragments as a result of a close approach to Jupiter, before colliding with the planet during the next passage in July 1994. We have recently developed an exact analytical theory for the distortion and disruption limits of spinning ellipsoidal bodies subjected to tidal forces, using the Drucker-Prager strength model with zero cohesion. This model is the appropriate one for dry granular materials such as sands and rocks, for rubble-pile asteroids and comets, as well as for larger planetary satellites, asteroids and comets for which the cohesion can be ignored. Here, we recall the general concept of this theory for which details and major results are given in a recent publication. In particular, we focus on the definition of “material strength”: while it has great implications this concept is often misunderstood in the community of researchers working on small bodies. Then, we apply our theory to a few real objects, showing that it can provide some constraints on their unknown properties such as their bulk density. In particular it can be used to estimate the maximum bulk density that a particular object, such as 99942 Apophis, must have to undergo some tidal readjustments during a predicted planetary approach. The limits of this theory are also discussed. The cases where internal cohesion cannot be ignored will then be investigated in the near future.
Collision and impact simulations including porosity
Authors: Benz Willy , Jutzi Martin 
Published: May 2007

AbstractThe Smooth Particle Hydrodynamics (SPH) impact code (Benz & Asphaug 1994) has been developed for the simulation of impacts and collisions involving brittle solids in the strength-and gravity-dominated regime. In the latter regime, the gravitational overburden is used to increase the fracture threshold. In this paper, we extend our numerical approach to include the effect of porosity at a sub-resolution scale by adapting the so-called P -α model (Herrman 1969). Using our extended 3D SPH impact code, we investigated collisions between porous bodies to examine the sensitivity of collisional outcomes to the degree of porosity. Two applications that illustrate the capabilities of our approach are shown: 1) the modeling of a Deep Impact-like impact and 2) the computation of the amount of momentum transferred to an asteroid following the impact of a high velocity projectile.
Space weathering and tidal effects among near-Earth objects
Authors: Marchi S. , Paolicchi P. , Nesvorný D. , Magrin S. , Lazzarin M. 
Published: May 2007

AbstractThe effect of the space weathering on the spectral properties of the S–complex asteroids (both Main Belt bodies and near–Earth asteroids) has been widely discussed in recent times. It has also shown that the evolution of spectral properties of planet–crossing bodies, and in particular of near–Earth asteroids (NEAs), is also affected by other physical processes, such as tidal resurfacing due to close encounters with planetary bodies. In this paper we show how to combine previous analyses with the purpose of obtaining a global model for NEAs space weathering.
Near-Earth objects as principal impactors of the Earth: Physical properties and sources of origin
Authors: Lupishko Dimitrij F. , Martino Mario Di , Binzel Richard P. 
Published: May 2007

AbstractNear-Earth objects (NEOs) are objects of a special interest from the point of view not only of cosmogonic problems of the Solar system, but of the applied problems as well (the problem of asteroid hazard, NEOs as the potential sources of raw materials, etc.). They are much smaller in sizes than main-belt asteroids (MBAs), very irregular in shape and covered with a great number of craters of different sizes. Most of NEOs are covered by regolith of low thermal inertia and different thickness. Objects with complex non-principal axis rotation (tumbling bodies) and with super-fast rotational periods have been detected among them. The new data, based on photometric and radar observations, evidence that about 15-20 %; of NEOs could be binary systems. Most of the classified NEOs fragments of differentiated assemblages of S-and Q-types. Analysis of physical properties of NEOs clearly indicates that the asteroid main-belt is the principal source of their origin and only about 10 % of NEOs have a cometary origin.