bluuebunny/crossref_metadata_2025_split huggingface dataset:
Defective Implant Osseointegration Under Protein Undernutrition: Prevention by PTH or Pamidronate
Authors: Dayer Romain , Badoud Isabelle , Rizzoli René , Ammann Patrick 
Published: June 2007

Abstract
Protein deficiency is associated with impaired titanium osseointegration. We studied whether systemic treatment with PTH or pamidronate could influence the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake. PTH or pamidronate prevented the deleterious effects of protein undernutrition on bone microarchitecture close to the implant and on mechanical fixation. PTH even significantly improved implant osseointegration.
Introduction: Protein deficiency is highly prevalent among elderly patients hospitalized in orthopedic wards. Reduced protein intake impairs titanium osseointegration in rats. Whether stimulator of bone formation or inhibitor of bone resorption could improve implant osseointegration under protein deprivation is not known. We studied the effects of systemic treatment with PTH or pamidronate on the resistance to pull-out of titanium rods implanted into rats proximal tibia under normal and isocaloric low protein intake.
Materials and Methods: We measured the resistance to pull-out 1-mm -diameter titanium rods implanted into the proximal tibias of 49 adult female rats receiving a normal or an isocaloric low protein diet. After 2 wk on either diet, the implants were inserted, and the rats received PTH(1–34), pamidronate or saline vehicle for 8 wk. The tibias were removed for μCT morphometry, followed by the evaluation of pull-out strength.
Results: Pull-out strength was lower in rats fed an isocaloric low protein diet compared with rats fed a normal protein intake (−29%). PTH and pamidronate significantly increased pull-out strength in animals fed a normal or a low protein diet, the effect of PTH being of higher magnitude. The PTH- or pamidronate-mediated increase in pull-out strength was associated with significant increases of relative bone volume, bone-to -implant contact, and trabecular thickness, whereas trabecular spacing was reduced, in the vicinity of the implants.
Conclusions: We confirmed that isocaloric low protein intake impairs titanium implant osseointegration. PTH or pamidronate prevented the deleterious effects of protein undernutrition and even significantly improved the implant osseointegration. These results indicate that systemic administration of PTH or pamidronate could be considered for preventing uncemented arthroplasty loosening in protein undernourished patients.
Stepfather Involvement and Adolescents’ Disposition Toward Having Sex
Authors: Menning Chadwick , Holtzman Mellisa , Kapinus Carolyn 
Published: June 2007

CONTEXT:  Existing literature suggests that stepfather relationships may be associated with adolescents’ attitudes toward sex. Given the large number of children living with stepfathers, these associations call for the attention of researchers and intervention programs. METHODS:  Attitudes toward sex among participants in the first wave (1994–1995) of the National Longitudinal Study of Adolescent Health (Add Health) who were living in households headed by biological mothers and stepfathers were analyzed using linear regression models. Parental involvement and maternal attitudes toward sex were included as predictors. RESULTS:  The greater the involvement between adolescents and their stepfathers, the less positively disposed adolescents are toward having sex; however, the association holds only for males. Females’ dispositions toward sex are tied to their religiosity and their mothers’ attitudes toward sex. Both males and females who are sexually experienced view sex more positively than do those who have never had sex. CONCLUSIONS:  Different factors influence males’ and females’ motivations to engage in sex, and intervention programs need to be structured with these differences in mind. Programs that work toward cultivating close relationships between stepfathers and stepchildren will likely be most effective for males, while programs that highlight the important role that mothers play in making clear their beliefs about the acceptability of teenagers’ sexual activity will likely be most effective for females.
Association Between Adolescent Pregnancy And a Family History of Teenage Births
Authors: East Patricia L. , Reyes Barbara T. , Horn Emily J. 
Published: June 2007

CONTEXT:  The extent to which young women’s risk of adolescent pregnancy is associated with having a mother who was a teenage parent, a sister who was a teenage parent or both is not known. METHODS:  A sample of 127 Latina and black adolescent females completed in‐depth surveys at three time points between 1994 and 2000. Logistic regression analyses were used to examine whether socioeconomic factors, mothers’ parenting characteristics and certain sibling relationship qualities explain the association between a family history of teenage births and young women’s risk of pregnancy. RESULTS:  Compared with young women with no family history of teenage births, young women whose sister had had a teenage birth and those whose sister and mother both had had teenage births were significantly more likely to experience a teenage pregnancy (odds ratios, 4.8 and 5.1, respectively). Young women who had only a sister who had had a teenage birth had greater odds of pregnancy than young women who had only a mother who had had a teenage birth (4.5). Having both a mother and a sister who had had teenage births was independently associated with an elevated risk of pregnancy (3.7), even after controlling for socioeconomic and mothers’ parenting characteristics. Frequent companionship with an older sister was associated with increased odds of teenage pregnancy (4.5); frequent conflict with an older sister who had had a teenage birth was marginally associated with decreased odds of the outcome (0.3). CONCLUSION:  Pregnancy prevention interventions targeting young women according to maternal and sibling teenage birth histories may be effective.
Removal and Quantification of Asian Tapeworm from Bonytail Chub Using Praziquantel
Authors: Ward David L 
Published: June 2007

Abstract
The spread of the Asian tapeworm Bothriocephalus acheilognathi has been identified as a potential threat to endangered cyprinid fishes, such as bonytail Gila elegans and humpback chub G. cypha. Praziquantel is often used to remove Asian tapeworms from these species, but little information is available on the effectiveness or side effects of these treatments. I performed laboratory experiments using bonytails (110–457 mm total length) to evaluate the dosage and time needed to effectively remove 100% of Asian tapeworms using praziquantel. A low dose of 0.7 mg/L for 24 h was not effective at removing all Asian tapeworms, whereas a 24-h exposure at 1.5 mg/L and higher was 100% effective. A bath treatment of 12-h duration only appears effective at the highest dose of 36 mg/L, but not all Asian tapeworms are cleared from the host within this time frame. No short-term mortality or side effects of praziquantel treatment were observed. Praziquantel bath treatments can effectively and safely remove 100% of Asian tapeworms from bonytail if dosage and treatment duration are adequate. In some cases, repeated treatments may be necessary to ensure that Asian tapeworms are not spread into new environments.
Data analysis for numerical and categorical individual time‐series
Authors: Saporta G. 
Published: June 2007

AbstractPrincipal components analysis and correspondence analysis may be generalized to handle time‐dependent data. For real‐valued data the basic tool is the Karhunen‐Loeve decomposition. For categorical processes harmonic analysis is presented in terms of reciprocal averaging. Details are given for approximated and interpolated solutions.
Classification of medullary lesions among paraplegic patients by the likelihood of the links method
Authors: Lerman I. C. 
Published: June 2007

AbstractRelative to the problem presented and treated by Parisot in an earlier issue of this journal,1 we present a new solution based on our approach of hierarchical classification. The methodology used, that we will describe in a concise way, allows us to organize either the set of the descriptive variables or the set of the individuals. Its extreme generality includes a set theoretic coding which respects faithfully the globality of the intrinsic nature of the descriptive variables. Very rich results are obtained in terms of classification trees reduced to their ‘significant’ levels. One of the most significant levels corresponds to the partition obtained by Parisot. The ‘significant’ nodes indicate the most relevant associations. The signification is conceived from the empirical distribution — on the successive tree levels — of association coefficients between partition and ‘preordonnance’ (i.e. total preorder on the set of unordered object pairs).
A theoretical model of interpurchase times
Authors: Kahn Barbara E. 
Published: June 2007

AbstractA theoretical model of interpurchase times at the individual level is developed. This model provides a bench‐mark for the expected regularity of a product's purchase cycle in the absence of any confounding external marketing activity. Products which empirically deviate from the theoretical expectations can then be further studied to determine the causes of the deviations. The theoretical model also tests the robustness of the assumption of a gamma distribution at the individual level, an assumption which is frequently made in the marketing literature.
The analysis of menstrual bleeding patterns: A review
Authors: Belsey E. M. , Farley T. M. M. 
Published: June 2007

AbstractPatterns of vaginal bleeding are an important factor in the acceptability of contraceptive methods. The analysis of data obtained from daily menstrual diary records is a major methodological problem to which no satisfactory solution exists. This review describes approaches to the analysis of bleeding patterns among contracepting and non‐contracepting women and reviews the difficulties involved. The reference period method, introduced to avoid the arbitrary rules and definitions required for an analysis based on the concept of a menstrual cycle, is discussed and its limitations presented. The review draws on reports of meetings convened by the World Health Organization and the University of Exeter Family Planning Unit to discuss issues in the analysis. Previously unpublished methods are summarized and areas of controversy and topics for further research are identified.
Numerical analysis for factorial data analysis. Part I: Numerical software — the package INDA for microcomputers
Authors: Chatelin F. , Belaid D. 
Published: June 2007

AbstractA large collection of factorial data analysis methods can be characterized by the following matrices: X, the k x n matrix of data, and A, B the symmetric positive definite matrices of size n, k which represent the chosen norms of ℝn, ℝk, respectively. All methods amount to computing the largest eigenvalues of U = XAXTB or the largest singular values of E = B1/2XA1/2. In Part I of this paper we begin by a geometrical and probabilistic interpretation of the various methods, showing how U and E are defined in each case. We then define the computational kernel for factorial data analysis. We conclude by devising the numerical aspects of software implementation for this kernel on microcomputers and presenting the package INDA.
Updating prognostic indices via regression models
Authors: O'quigley John , Moreau Thierry 
Published: June 2007

AbstractIn medical applications of survival analysis we are often interested in determining prognosis, and the adoption of statistical models in the establishment of a prognostic index has become common practice. The aim of this presentation is to examine the problem of re‐evaluation or the modification of any such index in the light of information subsequent to the initial assessment. Examples are given to highlight the approach.
Numerical analysis for factorial data analysis. Part II: Special purpose hardware—the programmable systolic array SARDA
Authors: Chatelin F. , Porta T. 
Published: June 2007

AbstractThe second part of this paper deals with the systolic implementation of the computational kernel for factorial data analysis, defined in Part I, on special‐purpose hardware. The framework of the study is that a sequence of different algorithms has to be performed on a unique hardware array. This fact has led us to the design of the programmable systolic array SARDA: this is a triangular array which consists of programmable nodes with local memory and programmable orthogonal connections.
Study of the plant recolonization process in a burnt heathland using a method of hierarchical classification
Authors: Tallur B. , Forgeard F. 
Published: June 2007

AbstractThe reinstallation of different plant‐species and their evolution during a ten‐year period in a heathland after a fire accident has been studied by using the algorithm of heirarchical classification based on correlation (ABC) introduced by Tallur.1 Classification under contiguity restraint of the set of observation points (subintervals of an experimental observation line) enables one to determine the ‘patches’ having uniform vegetation structure. Lerman's ‘local’ and ‘global’ statistics are used to condense the classification tree to its significant nodes and to choose the most significant partition. x2 statistics are proposed to test whether a given patch has a ‘significant’ vegetation structure and if the association between a patch and a plant species is significant. Evolution of the horizontal structure of vegetation is studied by comparing the sets of patches obtained at successive observation dates and the corresponding dominant species.
A general pure death process model and the distribution of the time required to remove a fixed number of elements
Authors: Shoukry E. M. 
Published: June 2007

AbstractThe present work derives the distribution of the time required to remove a fixed number of elements W < N, treating the problem as a pure death process with general death rate μn and initial number of elements N. The mean and variance of the distribution time are also obtained. The special case W = N is considered. The results of Sobel et al.1 turn out to be a special case of our results.
Optimality conditions for regenerative inventory systems under batch demands
Authors: Sahin Izzet 
Published: June 2007

AbstractWe consider a single‐item, continuous‐review, (s, S) inventory system, under complete backlogging and a constant procurement lead time. Demands occur in independent, identically distributed batches, separated by independent identically distributed intervals. The model also includes a class of periodic review systems as a special case. Of interest are the optimal control policies with respect to a stationary cost rate function, constructed to include ordering, holding and shortage costs. We study the structural properties of the cost rate function and report some new bounds and optimality conditions. An application of these to the computation and approximation of optimal policies is also discussed.
A comparison of counting process models for complicated life histories
Authors: Mau Jochen 
Published: June 2007

AbstractThe modern statistical theory for counting processes lends itself to flexible non‐parametric analyses of complicated life histories. Its application rests upon a statistical model of multiplicative intensities, adequately constructed for the objectives of the analysis and usually derived from an underlying stochastic model of an individual course of disease. It is shown how survival times and suitable stochastic partitionings of the time axis can yield statistical models of intermittent and multi‐state exposure to a risk of death which otherwise are deduced, under stronger assumptions, from Markovian illness–death processes. Aalen's linear regression model for counting processes is applied in a non‐standard context of intermittent exposure.
Current research directions in the development of expert systems based on belief networks
Authors: Cooper Gregory F. 
Published: June 2007

AbstractAn expert system is a computer program that is designed to solve problems at a level comparable to that of a human expert in a given domain. Often expert systems require a representation of uncertainty. This paper highlights some of the key developments in the history of representing uncertainty in expert systems. An uncertainty representation called belief networks is then introduced and its use in expert systems is motivated. The paper concludes with a discussion of current directions in belief network research.
Reliability analysis of a stand‐by system with repair and intermediate stocks for failed and repaired units
Authors: Brandt A. , Sulanke H. 
Published: June 2007

AbstractIn this paper we give a reliability analysis of a stand‐by system with repair, consisting ofNworking andNRstand‐by units. Failed and repaired units are collected in intermediate stocks. Concerning the delivery from the intermediate stocks we consider two rules: (i) the collected units are delivered in fixed time intervals; (ii) the units will be delivered when there arekunits accumulated. The system fails if a unit that has failed cannot be replaced by a stand‐by unit. Using a point process approach we derive approximations for the stationary availability and mean time between failures of the system. Numerical results show that the proposed approximations, which can be handled easily, work well.
On a new naturally indexed quick clustering method with a global objective function
Authors: Owsiński Jan W. 
Published: June 2007

AbstractA new clustering method is presented which proposes a class of objective functions and an algorithm which sub‐optimizes the objective functions over the whole space of partitions. The objective functions have a global nature, encompassing both the cluster contents and the cluster number. However, the accompanying suboptimization algorithm works according to a simple progressive merger scheme. The algorithmic scheme produces in a quite natural way an indexed hierarchy. The hierarchy index is not just tacked on to the method—see Diday and Moreau1—on the contrary, the algorithm refers directly to its values which measure, depending upon the particular formulation, either the relative affinity or the relative difference of the two clusters merged at a given level of hierarchy. In this way, the scale of hierarchy and hierarchy‐wise validity of clusters can easily be established, which is of great importance in analysing unstructured data sets whose generating process is unknown and can only be hypothesized after an initial structure had been established, e.g. owing to clustering, as is the case in pattern recognition—see Kaminuma2.
Foundations of the likelihood linkage analysis (LLA) classification method
Authors: Lerman I. C. 
Published: June 2007

AbstractThe aim of this paper is to present the concepts underlying an approach to data analysis using a hierarchical classification. The data can be provided by observation, experiment or knowledge. We begin by presenting the classical view of the context of data representation, in which the algorithm of hierarchical ascendant construction of the classification tree is set. The main notion in our method is one of ‘similarity’. The latter must be elaborated in the best way, taking into account the mathematical nature of the objects to be compared. In this elaboration, we adopt a set theoretic and combinatoric representation of the descriptive attributes, which are interpreted in terms of relations. On the other hand, we introduce a probability scale for similarity measurement by using a likelihood concept.
A bound for wilson's theorem (I)
Authors: Yanxun Chang 
Published: June 2007

AbstractIn 1975, Richard M. Wilson proved: Given any positive integers k ⩾ 3 and λ, there exists a constant v0 = v0(k, λ) such that v ϵ B(k,λ) for every integer v ⩾ v0 that satisfies λ(v − 1) ≡ 0(mod k − 1) and λv(v − 1) ≡ 0[mod k(k − 1)]. The proof given by Wilson does not provide an explicit value of v0. We try to find such a value v0(k, λ). In this article we consider the case λ = 1 and v ≡ 1[mod k(k − 1)]. We show that: if k ⩾ 3 and v = 1[mod k(k − 1)] where v > kkk5, then a B(v,k, 1) exists. © 1995 John Wiley & Sons, Inc.
Cycle structures of automorphisms of 2‐(v,k,1) designs
Authors: Webb Bridget S. 
Published: June 2007

AbstractAn automorphism of a 2−(v,k, 1) design acts as a permutation of the points and as another of the blocks. We show that the permutation of the blocks has at least as many cycles, of lengths n > k, as the permutation of the points. Looking at Steiner triple systems we show that this holds for all n unless n|Cp(n)| ⩽ 3, where Cp(n) is the set of cycles of length n of the automorphism in its action on the points. Examples of Steiner triple systems for each of these exceptions are given. Considering designs with infinitely many points, but with k finite, we show that these results generalize. © 1995 John Wiley & Sons, Inc.
The multiplier conjecture for the case n = 4n1
Authors: Weisheng Qiu 
Published: June 2007

AbstractIn this article we prove that in the case n = 4n1 if (v,2 · 7 · 31) = 1 and v is not divisible by 15, then the Second Multiplier Theorem holds without the assumption n1 > λ. This improves a result due to McFarland. © 1995 John Wiley & Sons, Inc.
On circuits and pancyclic line graphs
Authors: Benhocine A. , Clark L. , Köhler N. , Veldman H. J. 
Published: June 2007

AbstractClark proved that L(G) is hamiltonian if G is a connected graph of order n ≥ 6 such that deg u + deg v ≥ n – 1 – p(n) for every edge uv of G, where p(n) = 0 if n is even and p(n) = 1 if n is odd. Here it is shown that the bound n – 1 – p(n) can be decreased to (2n + 1)/3 if every bridge of G is incident with a vertex of degree 1, which is a necessary condition for hamiltonicity of L(G). Moreover, the conclusion that L(G) is hamiltonian can be strengthened to the conclusion that L(G) is pancyclic. Lesniak‐Foster and Williamson proved that G contains a spanning closed trail if |V(G)| = n ≥ 6, δ(G) ≥ 2 and deg u + deg v ≥ n – 1 for every pair of nonadjacent vertices u and v. The bound n – 1 can be decreased to (2n + 3)/3 if G is connected and bridgeless, which is necessary for G to have a spanning closed trail.
A generalization of Plantholt's theorem
Authors: Hilton A. J. W. 
Published: June 2007

AbstractLet K denote the complete graph K2n+1 with each edge replicated r times and let χ′(G) denote the chromatic index of a multigraph G. A multigraph G is critical if χ′(G) > χ′(G/e) for each edge e of G. Let S be a set of sn – 1 edges of K. We show that, for 0 < s ≦ r, G/S is critical and that χ′ (G/(S ∪{e})) = 2rn + r – s for all e ∈ E(G/S). Plantholt [M. Plantholt, The chromatic index of graphs with a spanning star. J. Graph Theory 5 (1981) 5–13] proved this result in the case when r = 1.
On the structure of hereditary classes of graphs
Authors: Scheinerman Edward R. 
Published: June 2007

AbstractA class of graphs is hereditary if it is closed under taking induced subgraphs. Classes associated with graph representations have “composition sequences” and we show that this concept is equivalent to a notion of “amalgamation” which generalizes disjoint union of graphs. We also discuss how general hereditary classes of graphs are built up from representation classes.
Circuits including a given set of vertices
Authors: Fraisse Pierre 
Published: June 2007

AbstractLet G = (V, E) be a digraph of order n, satisfying Woodall's condition ∀ x, y ∈ V, if (x, y) ∉ E, then d+(x) + d−(y) ≥ n. Let S be a subset of V of cardinality s. Then there exists a circuit including S and of length at most Min(n, 2s). In the case of oriented graphs we obtain the same result under the weaker condition d+(x) + d−(y) ≥ n – 2 (which implies hamiltonism).