bluuebunny/crossref_metadata_2025_split huggingface dataset:
Transformation of sperm nuclei into male pronuclei in nucleate and anucleate fragments of parthenogenetic mouse eggs
Authors: Borsuk Ewa , Tarkowski Andrzej K. 
Published: February 2005

AbstractOur objective was to examine the ability of nucleate and anucleate fragments of artificially activated mouse eggs to transform sperm nucleus into male pronucleus. To this end, zona‐free oocytes in metaphase II were activated by ethanol and bisected into halves (one with the spindle, the other anucleate) either within 10 to 20 min (series A) or 3 or 5 hr later (series B). In series A, the fragments were inseminated 3,5, and 8 h after activation, and in series B. 3 and 5 h after activation. Both nucleate and anucleate fragments lose the capability of transforming sperm nucleus into fully formed pronucleus sometime between 3 and 5 h after activation. In 8 h old parthenogenetic fragments, the majority of sperm nuclei remain unchanged or begin decondensation but never reach the stage of an early pronucleus. In over 1/3 of anucleate fragments of this age group, sperm nuclei develop defectively: chromatin decondenses inside the persisting nuclear envelope. In other experimental groups, the incidence of these abnormal sperm nuclei varies between 0 and 10%. In general, the anuclcate fragments retain the capability to transform sperm nuclei (fully or partially) longer than their nuclear counterparts. This difference may be accounted for by a different level of substances required for pronuclcar growth (extrachromosomal constituents of the germinal vesicle and nuclear lamins): high and constant in the cytoplasm of anucleate egg halves and low and progressively decreasing in the nucleate halves because of their putative uptake by the female pronucleus. However, the cytoplasmic factors responsible for the initial stages of transformation (nuclear envelope breakdown, chromatin decondensation) become eventually inactivated both in the presence and in the absence of a female pronucleus.
Catchlike property of skeletal muscle: Recent findings and clinical implications
Authors: Binder‐Macleod Stuart , Kesar Trisha 
Published: February 2005

AbstractThe catchlike property of skeletal muscle is the force augmentation produced by the inclusion of an initial, brief, high‐frequency burst of two to four pulses at the start of a subtetanic low‐frequency stimulation train. Catchlike‐inducing trains take advantage of the catchlike property of skeletal muscle and augment muscle performance compared with constant‐frequency trains, especially in the fatigued state. Literature spanning more than 30 years has provided comprehensive information about the catchlike property of skeletal muscle. The pattern of the catchlike‐inducing train that maximizes muscle performance is fairly similar across different muscles of different species and under various stimulation conditions. This review summarizes the mechanisms of the catchlike property, factors affecting force augmentation, techniques used to identify patterns of catchlike‐inducing trains that maximize muscle performance, and potential clinical applications to provide a historical and current perspective of our understanding of the catchlike property. Muscle Nerve, 2005
Skinned single fibers from normal and dystrophin‐deficient dogs incur comparable stretch‐induced force deficits
Authors: Childers Martin K. , Staley Jerry T. , Kornegay Joe N. , McDonald Kerry S. 
Published: February 2005

AbstractIntact dystrophin‐deficient canine muscles were previously shown to incur greater‐than‐normal stretch‐induced force deficits. Here we tested the hypothesis that maximally activated detergent‐treated (skinned) single fibers from normal and dystrophin‐deficient dogs would incur comparable force deficits after stretch. Skinned cranial sartorius (CS) fibers from dystrophin‐deficient and normal dogs were calcium‐activated (pCa 4.5) and rapidly stretched. A single 30% stretch induced force deficits of 27.07 ± 3.9% and 29.7 ± 4.8% in dystrophin‐deficient (n = 22) and normal (n = 18) fibers, respectively. Our data support the hypothesis that maximally activated skinned single fibers from normal and dystrophin‐deficient dogs incur comparable force deficits after stretch. Our findings suggest that knowledge of the extent of stretch‐induced force deficits following repeated stretch‐activations in the GRMD dog may be useful to assess future therapeutic interventions aimed at replacing dystrophin in the sarcolemmal membrane. Muscle Nerve, 2005
Temperature‐Dependent Growth of Germanium Oxide and Silicon Oxide Based Nanostructures, Aligned Silicon Oxide Nanowire Assemblies, and Silicon Oxide Microtubes
Authors: Hu Junqing , Jiang Yang , Meng Xiangmin , Lee Chun‐Sing , Lee Shuit‐Tong 
Published: February 2005

AbstractWe demonstrate the temperature‐dependent growth of germanium oxide and silicon oxide based composite nanostructures (multiple nanojunctions of Ge nanowires and SiOx nanowires, Ge‐filled SiO2 nanotubes, Ge/SiO2 coaxial nanocables, and a variety of interesting micrometer‐sized structures), aligned SiOx nanowire assemblies, and SiOx microtubes. The structures were characterized by SEM, TEM, energy‐dispersive X‐ray spectroscopy, and electron diffraction. The combination of laser ablation of a germanium target and thermal evaoporation of silicon monoxide powders resulted in the formation of Ge and SiOx species in a carrier gas; the nano/micro‐sized structures grow by either a Ge‐catalyzed vapor–liquid–solid or a Ge‐nanowire‐templated vapor–solid process.
Non‐invasive tests to predict fetal anemia in Kell‐alloimmunized pregnancies
Authors: van Dongen H. , Klumper F. J. C. M. , Sikkel E. , Vandenbussche F. P. H. A. , Oepkes D. 
Published: February 2005

AbstractObjectivesTo compare test characteristics of ultrasound and Doppler parameters in the prediction of fetal anemia in Kell‐alloimmunized pregnancies.MethodsIn this prospective study, 27 fetuses at risk for anemia due to Kell alloimmunization were evaluated with ultrasound and Doppler imaging. Spleen perimeter, liver length, middle cerebral artery (MCA) peak systolic velocity and intrahepatic umbilical venous (IHUV) maximum velocity were measured. Results were compared with fetal hemoglobin values at first intrauterine blood sampling or delivery. Severe fetal anemia was defined as a hemoglobin deficit of at least 5 SD below the mean for gestational age.ResultsEighteen fetuses were anemic and required intrauterine transfusions. In the other nine pregnancies no transfusions were performed; one of these fetuses was severely anemic at birth. MCA and IHUV flow velocities were the best predictors of fetal anemia in Kell alloimmunized fetuses (sensitivity 89% for each test). Sensitivities for spleen perimeter (15%) and liver length (14%) were disappointing.ConclusionsDoppler evaluation of MCA peak systolic velocity and IHUV maximum velocity can be used to reliably predict severe fetal anemia in Kell alloimmunization. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Improved first‐trimester Down syndrome screening performance by lowering the false‐positive rate: a prospective study of 9941 low‐risk women
Authors: Wøjdemann K. R. , Shalmi A. C. , Christiansen M. , Larsen S. O. , Sundberg K. , Brocks V. , Bang J. , Nørgaard‐Pedersen B. , Tabor A. 
Published: February 2005

AbstractObjectiveTo determine the performance of screening for Down syndrome (DS) and other major chromosomal abnormalities using nuchal translucency (NT), free β‐human chorionic gonadotropin (β‐hCG) and pregnancy‐associated plasma protein‐A (PAPP‐A) in a prospective study of a non‐selected population.MethodsOf 9941 women with an early ultrasound examination, NT was measured in 8622 singleton pregnancies with a gestational age between 10 + 3 and 13 + 6 weeks. β‐hCG and PAPP‐A were analyzed in 6441 cases. Detection rates (DR) and false‐positive rates (FPR) for the NT screening, the double test (β‐hCG and PAPP‐A) and the combined test (NT and the double test) were calculated using a 1 : 250 cut‐off.ResultsNT could be measured in 97.5% of cases. The DR for DS with NT screening alone was 75% with a FPR of only 1.8%. The double test detected 73% and the combined test 91%, for FPRs of 8.8% and 2.1%, respectively. We detected 80% of fetuses with other major chromosomal abnormalities with a combination of NT screening and other ultrasound findings. Low β‐hCG and PAPP‐A values (below 0.4 MoM) were observed in 0.5% of the women including all cases of triploidy and trisomy 18 and 13.ConclusionsThe performance of a screening strategy for DS using a combination of NT and the double test was superior to that using either NT or the double test alone due to a very low FPR and a higher DR. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Dynamic morphological changes in the anterior vaginal wall before and after laparoscopic Burch colposuspension in primary urodynamic stress incontinence
Authors: Yang J.‐M. , Yang S.‐H. , Huang W.‐C. 
Published: February 2005

AbstractObjectiveTo evaluate dynamic morphological changes in the anterior vaginal wall in primary urodynamic stress incontinence before and after laparoscopic Burch colposuspension and to explore the related effects on urethral and voiding functions.MethodsUltrasound cystourethrography and urodynamic study were performed in 112 patients with primary urodynamic stress incontinence before and 3 months after laparoscopic Burch colposuspension. Ultrasound assessment included measurement of the bladder neck positions at rest and during straining, the bladder wall thickness at the dome and trigone, and observation of the motion of the bladder neck in addition to the development of cystocele on Valsalva maneuver. On ultrasonography, a cystocele was defined as prolapse or descent of the bladder base below the bladder neck at rest, on Valsalva, or both.ResultsAfter laparoscopic Burch colposuspension, ultrasound cystourethrography revealed significant differences in the bladder neck position at rest and during stress (preoperative median 93° vs. postoperative 70° at rest and preoperative 160° vs. postoperative 81° during stress, P < 0.001, respectively) and rotational angle (preoperative median 58° vs. postoperative 10°, P < 0.001). A laparoscopic Burch operation corrected 50% (5/10) of the preoperative cystoceles. However, a residual cystocele developed postoperatively in 29% (30/102) of the women who did not have one previously. Postoperative ultrasonographic and urodynamic studies did not reveal any differences between those women with or without postoperative cystocele except for the residual urine volume, detrusor opening pressure, and straining and rotational angles of the bladder neck (P < 0.001, 0.032, 0.010 and < 0.001, respectively).ConclusionsLaparoscopic Burch colposuspension may correct a pre‐existing cystocele, but in other patients a cystocele may persist or be disclosed. After laparoscopic Burch operation a persistent cystocele is not associated with urethral compression or voiding impairment. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Nuchal translucency in pregnancies conceived after assisted reproduction technology
Authors: Hui P. W. , Tang M. H. Y. , Lam Y. H. , Yeung W. S. B. , Ng E. H. Y. , Ho P. C. 
Published: February 2005

AbstractObjectivesLevels of maternal serum markers of fetal Down syndrome in pregnancies conceived after assisted reproduction are different from those of normal spontaneous pregnancies. The present study examined the effects of conventional in‐vitro fertilization (IVF), intracytoplasmic sperm injection (ICSI) and embryo cryopreservation on nuchal translucency (NT) thickness.MethodsA retrospective analysis on 16 673 spontaneous pregnancies, 119 pregnancies with fresh embryos from IVF, 62 pregnancies with frozen‐thawed embryos from IVF, 81 pregnancies with fresh embryos from ICSI and 39 frozen‐thawed embryos from ICSI was performed. All were singletons with known normal outcomes. Multiples of the median (MoM) of NT were compared.ResultsThe median NT MoM of spontaneous pregnancies was 1.01. In the assisted reproduction pregnancies, the median NT MoM were significantly increased to 1.07 (P = 0.003), 1.09 (P = 0.009) and 1.09 (P = 0.001) in pregnancies conceived with fresh embryos from IVF, frozen‐thawed embryos from IVF and fresh embryos from ICSI, respectively. A non‐significant increase in median NT MoM (1.04; P = 0.489) was also observed in pregnancies with frozen‐thawed embryos from ICSI.ConclusionsIncreased NT in assisted reproduction pregnancies is postulated to be due to some delay in fetal development. Another possible reason might be related to adverse antenatal course in these pregnancies. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Direct effects of vitamin D3 analogues on G-protein mediated signalling systems in rat osteosarcoma cells and rat pituitary adenoma cells
Authors: Mortensen Berit M. , Lund Hanne W. , Jablonski Greg , Paulssen Ruth H. , Gordeladze Jan O. 
Published: February 2005

In normal rats treated with 1,25(OH)2D3 or 24,25(OH)2D3, serum Ca2+, ALP, PRL and GH are significantly altered. In order to study the primary effect of vitamin D3 analogues on target organ function, rat UMR 106 osteosarcoma and GH3 pituitary adenoma cells in monolayer culture were exposed accordingly.
Surprisingly, prolonged exposure of these cell lines to physiological levels of either 1,25(OH)2D3 or 24,25(OH)2D3 did not significantly affect the secretory parameters (ALP, PRL or GH) tested. However, 1,25(OH)2D3 exposure significantly reduced PTH- and Gpp(NH)p-elicited AC as well as Gpp(NH)p-stimulated PLC activities in the UMR 106 cells. These changes were accompanied by an increase and decrease in the membrane contents of the G-protein subunits G36β and Gq/11α, respectively. In contrast, 24,25(OH)2D3 remained without significant biological effect on these signalling systems despite concomitantly augmented levels of G36β. TRH- and Gpp(NH)p-elicited PLC activities in the GH3 cells were significantly reduced by 1,25(OH)2D3 with a concurrent reduction in cellular amounts of Gq/11α, however, 24,25(OH)2D3 did not significantly alter any signalling systems nor G-proteins analyzed.
It is concluded that the osteoblastic and pituitary cell secretion of ALP, PRL and GH remain unaffected by the presence of 1,25(OH)2D3 and 24,25(OH)2D3, despite distinct alterations in components of G-protein mediated signalling pathways. Hence, other factors like ambient Ca2+ may be responsible for the perturbed secretory patterns of ALP and PRL seen in vitamin D3 treated rats.
Mechanism of liposome destabilization by polycationic amino acids
Authors: Epand Richard M. , Lim Wendy 
Published: February 2005

Polycationic amino acids induce the leakage and fusion of liposomes containing anionic lipids. We have investigated the nature and extent of the changes in membrane physical properties caused by these polypeptides which could result in the observed membrane destabilization. We found that in the range of pH 5 to pH 7 both poly-l-histidine and poly-l-lysine were ineffective in shifting the bilayer to hexagonal phase transition temperature of dielaidoylphosphatidylethanolamine, either in the presence of absence of 1-palmitoyl-2-oleoylphosphatidylserine. We also studied the gel to liquid crystalline phase transition properties of 1:1 mixtures of phosphatidylserine and phosphatidylethanolamine, both in dimyristoyl forms as well as the 1-palmitoyl-2-oleoyl forms, as a function of pH and in the presence and absence of polycationic amino acids. We observed that these two lipids were largely miscible at all pH values and in the presence and absence of the polypeptides. However, there was some increased tendency for phase separation at higher pH and in the absence of polypeptide. Thus neither changes in curvature strain nor lateral phase separation induced by the polycationic amino acids could account for their marked ability to induce leakage and fusion.
Phosphatidylethanolamine labelled with pyrene on one of the acyl chains gives rise to fluorescent emission from both monomer and excimer forms. The ratio of emission intensity from these two forms is indicative of lateral phase separation and the degree of lateral mobility of this probe. In equimolar mixtures of the 1-palmitoyl-2-oleoyl forms of phosphatidylserine and phosphatidylethanolamine in the liquid crystalline phase at 30 °C we find little effect of pH on the ratio of excimer to monomer emission intensity. However poly-l-lysine markedly lowers the fraction of excimer emission from these liposomes through the pH range from 5 to 7. Poly-l-histidine lowers the excimer to monomer emission ratio at pH 5 but not at pH 7. This is opposite to what one would expect for lateral phase separation and is interpreted at being the consequence of the polypeptide lowering the rate of lateral diffusion of the lipids. This effect of poly-l-histidine is observed over a range of temperatures from 0 to 40°C in both gel and liquid crystalline phases. There is no evidence from the behaviour of the pyrene fluorescent probe for lipid interdigitation. We conclude that the promotion of leakage and fusion in anionic liposomes by polycationic amino acids is not a result of large changes in the physical properties or arrangements of the lipids but rather to a surface binding of the polyamino acids.
A transformation-based synthesis of temporal specifications
Authors: Noël Philippe 
Published: February 2005

Abstract
This paper is concerned with specifications expressed in propositional temporal logic with finite past extension. The variables of the specifications are partitioned into input variables, the value of which is determined by the environment, output variables, the value of which may be required by the environment, and internal variables. We present a method to synthesise temporal specifications, i.e. to rewrite them into a form from which a valuation for the output variables may be generated from the input values without backtracking. The transformed specification characterises the same set of input/output functions as the original specification, but in a more explicit way. A simple interpreter chooses the actual function to be used.
On simulation, subtyping and substitutability in sequential object systems
Authors: Maung Ian 
Published: February 2005

Abstract
The aim of this article is to clarify the concepts of behavioural subtype and substitutability that are used to establish the safety of dynamic binding and run-time polymorphism in object-oriented programming. A new model of object behaviour is introduced and used to define the states of an object and the notion of object type. A notion of simulation between object behaviours is defined and a subtype relation between object types is derived from it. The syntax and structural operational semantics of an elementary OOPL is given, and the concepts of object and type substitutability are defined. It is shown formally that simulation is equivalent to object substitutability and that subtyping is equivalent to type substitutability.
The formalization and analysis of a communications protocol
Authors: Bruns Glenn , Anderson Stuart 
Published: February 2005

Abstract
The MSMIE protocol [SBC89] allows processors in a distributed system to communicate via shared memory. It was designed to meet the reliability and efficiency needs of applications such as nuclear safety systems. We present a formal model of the MSMIE protocol expressed in the notation CCS. Desirable properties of the protocol are expressed in the modal mu-calculus, an expressive modal logic. We show that the protocol lacks an important liveness property. In actual operation, additional operating constraints are checked to avoid potential problems. We present a modified protocol and show that it possesses the liveness property even without checking operating constraints. We also show how parts of the analysis were automated with the Concurrency Workbench.
DUALITY: A simple formalism for the analysis of UNITY
Authors: Dijkstra Rutger M. 
Published: February 2005

Abstract
The ‘programming’ language DUALITY is presented and its utility for the description and analysis of UNITY is demonstrated. DUALITY is a simple language supporting demonic and angelic choice and two forms of tail-recursion. Starting from the predicate transformer semantics that was developed by C.S. Jutla, E. Knapp, and J.R. Rao for UNITY, we show that, given a UNITY program, we can write a program in DUALITY that has the same formal characteristics. This we use to reformulate and reprove some important theorems from the UNITY theory, viz. the ‘PSP-rule’ and the ‘completion rule’. Finally we show that the predicate transformers proposed by K.M. Chandy and B.A. Sanders for reasoning about concurrent computation also fit nicely within this framework.
Specification by interface separation
Authors: Hayes I. J. , Sanders J. W. 
Published: February 2005

Abstract
In specifying an operation it is often advantageous to describe it with abstract inputs and outputs whose concrete representation is described separately. For example, it is often convenient to describe as a set, input which in practice occurs as a sequence. The primary advantage of this approach is that one can initially concentrate on specifying an operation without the representations of its interface (that is, its inputs and outputs) obscuring the more important concerns of its abstract functional properties. Interface representations can be tackled independently, after the abstract functionality has been decided. Such separation of an operation into an abstract core and its interface with its environment makes the task of specification simpler, aids clarity of the result, and encourages reuse of both the abstract operation and its interface descriptions.
Compositional failure-based semantic models for Basic LOTOS
Authors: Valmari Antti , Tienari Martti 
Published: February 2005

Abstract
A systematic analysis of trace- and failure-based compositional semantic models for Basic LOTOS is presented. The analysis is motivated by the fact that the weakest known equivalences preserving sufficient information for several typical verification tasks are failure-based, and the weakness of an equivalence can be advantageous for verification. Both the equivalences and the preorders corresponding to the semantic models are covered. The analysis yields in a natural way two compositional semantic models, which are particularly suited for the verification of a general class of liveness properties, a task which cannot be performed with most established models.
Using a formal specification contractually
Authors: O'Halloran C. , Arthan R. , King D. 
Published: February 2005

Abstract
A commonly made criticism of formal methods is that they increase costs. Selective use of formal methods to define critical requirements can, however, lead to a significant decrease in lifecycle costs. In particular the economic and technical benefits of outsourcing the development of software can be fully realized and the cost of outsourcing slightly reduced by use of a formal specification. In this paper we describe a development in which a formal specification prepared by the customer formed part of the contract with the supplier. We conclude that this use of a formal specification can reduce risks and costs for all concerned and can help foster fruitful and co-operative relations in situations which are often fraught with confrontation.
The connection between initial and unique solutions of domain equations in the partial order and metric approach
Authors: Baier Christel , Majster-Cederbaum Mila 
Published: February 2005

AbstractThe purpose of this paper is twofold: First, we show in which way the initial solution of a domain equation for cpo's and the unique solution of a corresponding domain equation for metric spaces are related. Second, we present a technique to lift a given domain equation for cpo's to a corresponding domain equation for metric spaces.