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Inventory management practices and their implications on perceived planning performance

This paper focuses on the use of material planning methods to control material flow to inventories of purchased items. The first sub-objective is to evaluate the perceived planning performance of material planning methods used to control material flows in different inventory types in manufacturing and distribution companies. The second sub-objective is to evaluate the difference in perceived plann

The influence of interaction type and feeding location on the phylogeographic structure of the yucca moth community associated with Hesperoyucca whipplei

The interactions between herbivorous insects and their host plants have been central in generating diversification in both groups. We used a community of four yucca moth species, monophagous on the host plant Hesperoyucca whipplei (Agavaceae), to examine how the type of interaction and where insects feed within a plant influence phylogeographic structure of herbivorous insects. These four species

Chondroitin sulfate perlecan enhances collagen fibril formation - Implications for perlecan chondrodysplasias

Inactivation of the perlecan gene leads to perinatal lethal chondrodysplasia. The similarity to the phenotypes of the Col2A1 knock-out and the disproportionate micromelia mutation suggests perlecan involvement in cartilage collagen matrix assembly. We now present a mechanism for the defect in collagen type II fibril assembly by perlecan-null chondrocytes. Cartilage perlecan is a heparin sulfate or

Pulmonary sequelae of prolonged total venoarterial bypass: evaluation with a new experimental model

Total normothermic venoarterial bypass was established in 6 healthy pigs over a period of 18 hours. A heparin-coated closed extracorporeal system was used and no heparin was administered systemically. During the bypass period the main pulmonary artery was occluded and the heart was maintained in a beating state. All the animals maintained stable hemodynamics and normal blood gases during the entir

The cost of polygyny - definitions and applications

The polygyny threshold model was introduced in the 1960s in order to explain why females in some species choose to mate vith already mated males. Since then, a number of complementary or alternative hypotheses have been suggested. By using a hierarchical testing approach Searcy and Yasukawa (1989) organised the models that proposed to explain the maintenance of territorial polygyny. Here, I point

Factors for glaucoma progression and the effect of treatment - The Early Manifest Glaucoma Trial

Objective: To assess factors for progression in the Early Manifest Glaucoma Trial (EMGT), including the effect of EMGT treatment. Setting/Participants: Two hundred fifty-five open-angle glaucoma patients randomized to argon laser trabeculoplasty plus topical betaxolol or no immediate treatment (129 treated; 126 controls) and followed up every 3 months. Methods: Progression was determined by perime

The fate of mechanically induced cartilage in an unloaded environment

According to mechanobiologic theories, persistent intermittent mechanical stimulation is required to maintain differentiated cartilage. In a rat model for bone repair, we studied the fate of mechanically induced cartilage after unloading. In three groups of rats, regenerating mesenchymal tissue was submitted to different loading conditions in bone chambers. Two groups were immediately killed after

Scandinavian Sarcoma Group Osteosarcoma Study SSG VIII: prognostic factors for outcome and the role of replacement salvage chemotherapy for poor histological responders

From 1990 to 1997, 113 eligible patients with classical osteosarcoma received neo-adjuvant chemotherapy consisting of high-dose methotrexate, cisplatin and doxorubicin. Good histological responders continued to receive the same therapy postoperatively, while poor responders received salvage therapy with an etoposide/ifosfamide combination. With a median follow-up of 83 months, the projected metast

Envelope crossing distributions for Gaussian fields

The envelope process is an analytical tool often used to study extremes and wave groups. In an approach to approximate the first passage probability for the underlying response the average number of envelope crossings is used to obtain an upper bound. In the first part of the paper, we review the approach as well as give a brief account of the previous results with some focus on the contribution

Generation of attosecond pulses with ellipticity-modulated fundamental

We have studied experimentally and theoretically high-order harmonic generation using a laser field with a time-dependent ellipticity. We show that the harmonic emission can be confined into a narrow temporal window, in which the fundamental polarization is quasi-linear. This allows a single attosecond pulse (200 as) with a fundamental field obtained from 10 fs pulse to be generated.

Directional selection on morphology In the pheasant, Phasianus colchicus

Directional selection was relatively frequent, and in some instances intense, during a three-year study of a pheasant population. The pheasant is a polygynous species. In addition to weight, tarsus length and wing length, which were studied in both sexes, three beak characters were measured in females, and tail and spur length in males. Both univariate and multivariate techniques were used to esti

Backward retrieval in optical quantum memory controlled by an external field

A scheme for backward retrieval in optical quantum memories in which information is stored in collective states of an extended resonant atomic ensemble is developed such that phase conjugation can be implemented by application of an external nonuniform electric (magnetic) field without use of coherent exciting pulses. The possibilities of realizing such a scheme using resonant solid-state material

Particle trajectories in linear deep-water waves

Using phase plane analysis we show that within the framework of linear water wave theory the particle paths in a deep-water wave are not closed: there is a forward drift over a period, which decreases with greater depth.

mTHPC pharmacokinetics following topical administration

Measurements of concentration of sensitizers for photodynamic therapy can provide important information in the dosimetry planning and can also give input to the optimal time for treatment. There has been skepticism towards fluorescence techniques for this purpose, as the signal depends on the fluorescence yield and optical properties of the tissue. Absorption based techniques, lack on the other ha

Very high resolution ultraviolet spectroscopy of a chemically peculiar star: Results of the chi Lupi Pathfinder project

We summarize here the results of a major eight-year investigation of the extraordinarily detailed UV spectrum of the sharp-lined, nonmagnetic, main-sequence, chemically peculiar star chi Lupi (B9.5p HgMn + A2 Vm). The UV observations are composed of 345 Angstrom of the spectrum acquired with the Goddard High Resolution Spectrograph (GHRS) on board the Hubble Space Telescope at an average resolutio

Expression of calcium channel Ca(v)1.3 in cat spinal cord: Light and electron microscopic immunohistochemical study

In spinal neurons, plateau potentials serve to amplify neuronal input signals. To a large extent, the underlying persistent inward current is mediated by a subtype of the L-type calcium channel (Ca(v)1.3). In the present investigation, we have studied its distribution and cellular localization in the cat spinal cord by light and electron microscopic immunohistochemistry. The results show that Ca(v

Reliability of Low-Radiation Dose CT in the Assessment of Screw Placement After Posterior Scoliosis Surgery, Evaluated With a New Grading System

Study Design. A retrospective study. Objective. To evaluate the reliability of computed tomography (CT) with low radiation dose in the assessment of implant status in patients with adolescent idiopathic scoliosis (AIS). Summary of Background Data. The use of all-pedicle screw construct in scoliosis corrective surgery continues to gain increasing popularity since their introduction 1994 although th

Neutron star binaries and long-duration gamma-ray bursts

Cosmological long-duration gamma-ray bursts (LGRBs) are thought to originate from the core collapse to black holes (BHs) of stripped massive stars. Those with sufficient rotation form a centrifugally supported torus whose collapse powers the GRB. We investigate the role of tidal locking within a tight binary as a source of the necessary angular momentum. We find that the binary orbit must be no wi

Direct and inverse scattering for transient electromagnetic waves in nonlinear media

Nonlinear propagation of electromagnetic waves is an important problem in optics. Often the properties of the nonlinear media are not fully understood. The solution of an inverse problem can provide an aid to that understanding. An inverse transmission problem is posed; it is one of reconstructing the medium parameters, by measurement of a wave that has been propagated through the nonlinear mediu