bluuebunny/crossref_metadata_2025_split huggingface dataset:
Long‐term delivery of FGF‐6 changes the fiber type and fatigability of muscle reinnervated from embryonic neurons transplanted into adult rat peripheral nerve
Authors: Grumbles Robert M. , Casella Gizelda T. B. , Rudinsky Michelle J. , Wood Patrick M. , Sesodia Sanjay , Bent Melissa , Thomas Christine K. 
Published: May 2007

AbstractMotoneuron death leads to muscle denervation and atrophy. Transplantation of embryonic neurons into peripheral nerves results in reinnervation and provides a strategy to rescue muscles from atrophy independent of neuron replacement in a damaged or diseased spinal cord. But the count of regenerating axons always exceeds the number of motor units in this model, so target‐derived trophic factor levels may limit reinnervation. Our aim was to examine whether long‐term infusion of fibroblast growth factor‐6 (FGF‐6) into denervated medial gastrocnemius muscles improved the function of muscles reinnervated from neurons transplanted into nerve of adult Fischer rats. Factor delivery (10 μg, 4 weeks) began after sciatic nerve transection. After a week of nerve degeneration, 1 million embryonic day 14–15 ventral spinal cord cells were transplanted into the distal tibial stump as a neuron source. Ten weeks later, neurons that expressed motoneuron markers survived in the nerves. More myelinated axons were in nerves to saline‐treated muscles than in FGF‐6‐treated muscles. However, each group showed comparable reductions in muscle fiber atrophy because of reinnervation. Mean reinnervated fiber area was 43%–51% of non‐denervated fibers. Denervated fiber area averaged 11%. FGF‐6‐treated muscles were more fatigable than other reinnervated muscles but had stronger motor units and fewer type I fibers than did saline‐treated muscles. FGF‐6 thus influenced function by changing the type of fiber reinnervated by transplanted neurons. Deficits in FGF‐6 may also contribute to the increase in type I fibers in muscles reinnervated from peripheral axons, suggesting that the effects of FGF‐6 on fiber type are independent of the neuron source used for reinnervation. © 2007 Wiley‐Liss, Inc.
Role of TPH‐2 in brain function: News from behavioral and pharmacologic studies
Authors: Invernizzi Roberto W. 
Published: May 2007

AbstractThe recent discovery of TPH‐2, a new isoform of tryptophan hydroxylase, the enzyme that catalyses the transformation of tryptophan into 5‐hydroxytryptophan and the rate‐limiting step in brain serotonin (5‐HT) biosynthesis, has boosted new interest in the many functions of 5‐HT in the brain and non‐nervous tissues. Recent studies on TPH‐2 are reviewed with particular attention to the role of this enzyme in behavior and in response to drugs as assessed by comparing strains of mice carrying a functional polymorphism of TPH‐2. Most studies concur to indicate that 5‐HT synthesis through TPH‐2 influence nervous tissues whereas TPH‐1 is responsible for the synthesis and action of 5‐HT in peripheral organs. Partial impairment of brain 5‐HT synthesis caused by polymorphism of the gene encoding TPH‐2 causes reduced release of the neurotransmitter, increased aggressiveness, and alters the response to drugs inhibiting the reuptake of 5‐HT. Strain comparison might be a useful strategy to investigate the genotype‐dependent alterations of TPH‐2. © 2007 Wiley‐Liss, Inc.
Developmental changes in the association of NMDA receptors with lipid rafts
Authors: Besshoh Shintaro , Chen Sheng , Brown Ian R. , Gurd James W. 
Published: May 2007

AbstractLipid rafts (LR) are lipid microdomains present in the cell surface membrane that are organizational platforms involved in protein trafficking and formation of cell signaling complexes. In the adult brain, NMDA receptors (NMDAR) and receptor‐associated proteins such as membrane‐associated guanylate kinases (PSD‐95 and SAP102), are distributed between the postsynaptic density (PSD) and lipid rafts. However, the time course of the association of NMDAR with LR during neural development is not known. We therefore investigated the effect of development on the association of NMDAR with LR prepared from rat brains ranging in postnatal age from 1–35 days and compared this with their expression in PSDs. LR and PSD fractions were prepared by extraction of P2 membranes with Tx‐100 followed by sucrose density gradient centrifugation. The yield of LR, as reflected by levels of protein, Thy‐1, and flotillin‐1 increased during postnatal development. NR2A was associated predominantly with the lipid raft fraction at all ages examined whereas NR2B underwent a gradual shift from PSDs to lipid rafts during the first 3 weeks after birth. These changes in the distribution of NR2A and NR2B were paralleled by changes in the distribution of PSD‐95 and SAP102 respectively. Tyrosine‐phosphorylated proteins, including NR2A and NR2B, were preferentially associated with lipid rafts in older, as compared to younger, animals. These results show that the association of NMDAR with LR is regulated developmentally. © 2007 Wiley‐Liss, Inc.
Origin identification on the commercial samples of Aurantii Fructus
Authors: Chuang Ching‐Ching , Wen Wu‐Che , Sheu Shuenn‐Jyi 
Published: May 2007

AbstractA total of 50 commercial samples of Aurantii Fructus, originating from Poncitrus trifoliata for Aurantii Fructus Immaturus, Citrus aurantium, and C. wilsonii for Aurantii Fructus Maturus, respectively, were collected from Taiwan and China herbal markets. Contents of the constituents in the samples were determined within 60 min using a developed HPLC method, which had been validated in terms of precision, repeatability, and accuracy. The results of the analyses showed that the constituents were closely related to the species and also the degree of maturity of the fruits, especially in the case of hesperidin (HE), naringin (NG), neohesperidin (NE), naringenin‐7‐glucoside (NGC), narirutin (NR), and quercetin (QU). The mature fruits (C. aurantium and C. wilsonii) contained chiefly NG, HE, and NE and the immature ones (P. trifoliata) had NG, NR, and QU majorly. Within the mature samples, the ratios of HE/NE and NGC/NE values were higher than 2.94 and 0.21 in C. aurantium and lower than 1.31 and 0.02 in C. wilsonii, respectively. A flowchart that is useful for identifying Aurantii Fractus was devised, based on the various chemical identification methods.
Development of SPE for recovery of polysaccharides and its application to the determination of monosaccharides composition of the polysaccharide sample of a lactobacillus KLB 58
Authors: Baik Yoon Suk , Cheong Won Jo 
Published: May 2007

AbstractA new SPE cartridge has been prepared in this study to purify polysaccharides of high molecular weights. A porous nonpolar styrene–divinylbenzene copolymer phase (Hamilton PRP‐1) was used to make the new cartridge. The cartridge was conditioned with methanol, water, and ACN in sequence, and the sample dissolved in a small amount of water was loaded. Impurities of low molecular weights were removed first by elution of 80:20 or 90:10 v/v% ACN/water, and polysaccharides were quantitatively recovered by elution of 50:50 v/v% ACN/water or pure water. The recovery of pure dextran 10000 was 90–95%. The SPE method was applied to purification of the polysaccharide sample of KLB58, a new lactobacillus discovered in Korea. The purified KLB 58 sample (weight recovery after SPE purification; 60%) was hydrolyzed for analysis of composition of monosaccharides. The hydrolysate was found to be composed primarily of fructose, glucose, galactose, rhamnose, mannose with small amounts of fucose and ribose.
Protein sequence information by matrix‐assisted laser desorption/ionization in‐source decay mass spectrometry
Authors: Hardouin Julie 
Published: May 2007

AbstractProteins from biological samples are often identified by mass spectrometry (MS) with the two following “bottom‐up” approaches: peptide mass fingerprinting or peptide sequence tag. Nevertheless, these strategies are time‐consuming (digestion, liquid chromatography step, desalting step), the N‐ (or C‐) terminal information often lacks and post‐translational modifications (PTMs) are hardly observed. The in‐source decay (ISD) occurring in a matrix assisted laser desorption/ionization (MALDI) source appears an interesting analytical tool to obtain N‐terminal sequence, to identify proteins and to characterize PTMs by a “top‐down” strategy. The goal of this review deals with the usefulness of the ISD technique in MALDI source in proteomics fields. In the first part, the ISD principle is explained and in the second part, the use of ISD in proteomic studies is discussed for protein identification and sequence characterization. © 2007 Wiley Periodicals, Inc., Mass Spec Rev 26:672–682, 2007
Molecular modeling of adenosine receptors: new results and trends
Authors: Martinelli Adriano , Tuccinardi Tiziano 
Published: May 2007

AbstractAdenosine is a ubiquitous neuromodulator, which carries out its biological task by stimulating four cell surface receptors (A1, A2A, A2B, and A3). Adenosine receptors (ARs) are members of the superfamily of G protein‐coupled receptors (GPCRs). Their discovery opened up new avenues for potential drug treatment of a variety of conditions such as asthma, neurodegenerative disorders, chronic inflammatory diseases, and many other physiopathological states that are believed to be associated with changes in adenosine levels. Knowledge of the 3D structure of ARs could be of great help in the task of understanding their function and in the rational design of specific ligands. However, since GPCRs are membrane‐bound proteins, high‐resolution structural characterization is still an extremely difficult task. For this reason, great importance has been placed on molecular modeling studies and, particularly in the last few years, on homology modeling (HM) techniques. The publication of the first high‐resolution crystal structure for bovine rhodopsin (bRh), a GPCR superfamily member, provides the option of utilizing HM to generate 3D models based on detailed structural information. In this review we report, analyze, and compare the main experimental data, computational HM procedures and validation methods used for ARs, describing in detail the most successful results. © 2007 Wiley Periodicals, Inc. Med Res Rev, 28, No. 2, 247–277, 2008
DNA methylation and chromatin accessibility of the proximal Cyp19 promoter region 1.5/2 correlate with expression levels in sheep placentomes
Authors: Fürbass Rainer , Selimyan Roza , Vanselow Jens 
Published: May 2007

AbstractPlacental oestrogens play an important role as local regulators of placental growth and differentiation during gestation, and toward term they are also involved in the preparation of parturition. They are synthesized within the fetal cotyledons of placentomes by aromatase cytochrome P450 (P450arom; EC 1.14.14.1), the product of the Cyp19 gene. The first step of regulation of P450arom expression, and hence enzyme activity and oestrogen production, takes place at the level of Cyp19 transcription, which is driven by a proximal promoter region, P1.5/2, in the sheep placenta. The aim of the present study was to find out if different Cyp19 expression levels, which previously had been observed in ovine placentome tissues, correlate with the tissue‐specific chromatin structure of the promoter. To this end, we investigated the chromatin structure across the P1.5/2 region in caruncles and cotyledons from 100 and 125 days pregnant ewes, and in term placentae, respectively, by analyzing the DNA methylation and the accessibility to restriction digestion. Our data show that: (1) cotyledonal DNA was significantly lower methylated than caruncular DNA; (2) methylation of cotyledonal DNA was low at 100 and 125 days of pregnancy, and increased to a significant higher level in term placentae; and (3) concurrently, cotyledonal chromatin became inaccessible to restriction digestion at term of gestation. The results imply that DNA methylation and chromatin accessibility of the P1.5/2 promoter region correlate with expression levels of the Cyp19 gene. Mol. Reprod. Dev. 75: 1–7, 2008. © 2007 Wiley‐Liss, Inc.
Optimal dispatching strategies for vehicles having exponentially distributed trip times
Authors: Asgharzadeh Kamran , Newell G. F. 
Published: May 2007

AbstractA transportation system has N vehicles with no capacity constraint which take passengers from a depot to various destinations and return to the depot. The trip times are considered to be independent and identically distributed random variables. The dispatch strategy at the depot is to dispatch immediately, or to hold any returning vehicles with the objective of minimizing the average wait per passenger at the depot, if passengers arrive at a uniform rate.Optimal control strategies and resulting waits are determined in the special case of exponentially distributed trip time for various N up to N = 15. For N ≫ 1, the nature of the solution is always to keep a reservoir of vehicles in the depot, and to decrease (increase) the time headway between dispatches as the size of the reservoir gets larger (smaller). For sufficiently large N, one can approximate the number of vehicles in the reservoir by a continuum and obtain analytic experession for the optimal dispatch rate as a function of the number of vehicles in the reservoir. For the optimal strategy, it is shown that the average number of vehicles in the depot is of order N1/3. These limit properties are expected to be quite insensitive to the actual trip time distribution, but the convergence of the exact properties to the continuum approximation as N → ∞ is very slow.
Probabilistic formulations of the multifacility weber problem
Authors: Aly Adel A. , White John A. 
Published: May 2007

AbstractThe problem considered is to locate one or more new facilities relative to a number of existing facilities when both the locations of the existing facilities, the weights between new facilities, and the weights between new and existing facilities are random variables. The new facilities are to be located such that expected distance traveled is minimized. Euclidean distance measure is considered; both unconstrained and chance‐constrained formulations are treated.
The constrained shortest path problem
Authors: Aneja Y. P. , Nair K. P. K. 
Published: May 2007

AbstractThe shortest path problem between two specified nodes in a general network possesses the unimodularity property and, therefore, can be solved by efficient labelling algorithms. However, the introduction of an additional linear constraint would, in general, destroy this property and the existing algorithms are not applicable in this case. This paper presents a parametric approach for solving this problem. The algorithm presented would require, on the average, a number of iterations which is polynomially bounded. The similarity of this approach to that of the generalized Lagrange multiplier technique is demonstrated and a numerical example is presented.
An algorithm for 0‐1 multiple‐knapsack problems
Authors: Hung Ming S. , Fisk John C. 
Published: May 2007

AbstractThe 0‐1 multiple‐knapsack problem is an extension of the well‐known 0‐1 knapsack problem. It is a problem of assigning m objects, each having a value and a weight, to n knapsacks in such a way that the total weight in each knapsack is less than its capacity limit and the total value in the knapsacks is maximized.A branch‐and‐bound algorithm for solving the problem is developed and tested. Branching rules that avoid the search of redundant partial solutions are used in the algorithm. Various bounding techniques, including Lagrangean and surrogate relaxations, are investigated and compared.
Estimating value in a uniform auction
Authors: Samaniego Francisco J. , Kaiser Lee D. 
Published: May 2007

AbstractConsider an auction in which increasing bids are made in sequence on an object whose value θ is known to each bidder. Suppose n bids are received, and the distribution of each bid is conditionally uniform. More specifically, suppose the first bid X1 is uniformly distributed on [0, θ], and the ith bid is uniformly distributed on [Xi−1, θ] for i = 2, …︁, n. A scenario in which this auction model is appropriate is described. We assume that the value θ is un known to the statistician and must be esimated from the sample X1, X2, …︁, Xn. The best linear unbiased estimate of θ is derived. The invariance of the estimation problem under scale transformations in noted, and the best invariant estimation problem under scale transformations is noted, and the best invariant estimate of θ under loss L(θ, a) = [(a/θ) − 1]2 is derived. It is shown that this best invariant estimate has uniformly smaller mean‐squared error than the best linear unbiased estimate, and the ratio of the mean‐squared errors is estimated from simulation experiments. A Bayesian formulation of the estimation problem is also considered, and a class of Bayes estimates is explicitly derived.
A generalized‐indices transportation problem
Authors: Bammi Deepak 
Published: May 2007

AbstractA generalized‐indices transportation problem is formulated and an algorithm is presented for its solution. The algorithm is an extension of the modi‐method. A theorem on the number of independent variables in the generalized‐indices transportation problem is proved. An example problem is solved for the four‐indices transportation problem. A computer program has been written to solve any four‐indices problem.
A problem in network interdiction
Authors: Golden Bruce 
Published: May 2007

AbstractSuppose we are given a network G=(V,E) with arc distances and a linear cost function for lengthening arcs. In this note, we consider a network‐interdiction problem in which the shortest path from source node s to sink node t is to be increased to at least τ units via a least‐cost investment strategy. This problem is shown to reduce to a simple minimum‐cost‐flow problem. Applications and generalizations are discussed, including the multiple‐destination case.
Convex/stochastic programming and multilocation inventory problems
Authors: Karmarkar Uday S. 
Published: May 2007

AbstractThis paper examines a convex programming problem that arises in several contexts. In particular, the formulation was motivated by a generalization of the stochastic multilocation problem of inventory theory. The formulation also subsumes some “active” models of stochastic programming. A qualititative analysis of the problem is presented and it is shown that optimal policies have a certain geometric form. Properties of the optimal policy and of the optimal value function are described.
Adaptive disposal models
Authors: Derman C. , Lieberman G. J. , Ross S. M. 
Published: May 2007

AbstractThis paper reconsiders the classical model for selling an asset in which offers come in daily and a decision must then be made as to whether or not to sell. For each day the item remains unsold a continuation (or maintenance cost)cis incurred. The successive offers are assumed to be independent and identically distributed random variables having an unknown distributionF. The model is considered both in the case where once an offer is rejected it may not be recalled at a later time and in the case where such recall of previous offers is allowed.
Least‐absolute‐value estimators for one‐way and two‐way tables
Authors: Armstrong R. D. , Frome E. L. 
Published: May 2007

AbstractThis paper concerns itself with the problem of estimating the parameters of one‐way and two‐way classification models by minimization of the sum of the absolute deviations of the regression function from the observed points. The one‐way model reduces to obtaining a set of medians from which optimal parameters can be obtained by simple arithmetic manipulations. The two‐way model is transformed into a specially structured linear programming problem, and two algorithms are presented to solve this problem. The occurrence of alternative optimal solutions in both models is discussed, and numerical examples are presented.
The next decade of logistics research
Authors: Wagner Harvey M. 
Published: May 2007

AbstractPathbreaking logistics research over the next 10 years will focus on systems problems. Whereas past research generally has taken a “bottom‐up” approach, future investigations are likely to pursue a “top‐down” philosophy. Specifically, attention will concentrate on diagnosis of systems' improvement potentials; easy‐to‐use analytic approaches, inherently approximative, will be devised for quickly ascertaining whether a complex operating system can be substantially and effectively improved. Theories to assist in overall systems design, particularly the setting of boundaries and buffers among systems components, will be developed. At the same time, techniques for accurately forecasting future systems performance will be investigated.Underlying such research will be efforts to gain better understanding of management information requirements, including approaches for monitoring systems performance and providing early warning detection of systems degradation Improved management information systems will have to be coupled with appropriate design of managerial organizations and assignment of decision making responsibilities. Important avenues of research will he development of robust approaches, that is, both mathematical techniques and organizational approaches that are not too adversely affected by limited data, a changing environment, and human frailly.Finally, critical research will be directed at the implementation process, especially the interaction among initiation, design, testing and ultimate adoptionThis prognosis will explore the above themes in the context of large‐scale, complex systems. The decision areas will encompass inventory replenishment, multiechelon hierarchies for stockage and maintenance, procurement, transportation, scheduling, facilities planning, budgeting, reliability and personnel management.
The asymptotic distribution of order statistics
Authors: Weiss Lionel 
Published: May 2007

AbstractFor each n., X1(n), X2(n), …, Xn(n) are IID, with common pdf fn(x). y1(n) < … < Yn (n) are the ordered values of X1 (n), …, Xn(n). Kn is a positive integer, with lim Kn = ∞. Under certain conditions on Kn and fn (x), it was shown in an earlier paper that the joint distribution of a special set of Kn + 1 of the variables Y1 (n), …, Yn (n) can be assumed to be normal for all asymptotic probability calculations. In another paper, it was shown that if fn (x) approaches the pdf which is uniform over (0, 1) at a certain rate as n increases, then the conditional distribution of the order statistics not in the special set can be assumed to be uniform for all asymptotic probability calculations. The present paper shows that even if fn (x) does not approach the uniform distribution as n increases, the distribution of the order statistics contained between order statistics in the special set can be assumed to be the distribution of a quadratic function of uniform random variables, for all asymptotic probability calculations. Applications to statistical inference are given.
Nonextreme point solution strategies for linear programs
Authors: Cooper Leon , Kennington Jeff 
Published: May 2007

AbstractThis exposition presents two algorithms for linear programs which allow a value change in more than one nonbasic variable at each iteration. The computational formulae are developed and errors which have appeared in the literature are noted. One algorithm is a multiple basis exchange procedure while the second is a feasible direction method. There remain many computational challenges in the area of linear programming and we hope that this investigation will encourage additional work in the directions indicated in this exposition.