bluuebunny/crossref_metadata_2025_split huggingface dataset:
Burrowing in marine muds by crack propagation: kinematics and forces
Authors: Dorgan Kelly M. , Arwade Sanjay R. , Jumars Peter A. 
Published: November 2007

SUMMARYThe polychaete Nereis virens burrows through muddy sediments by exerting dorsoventral forces against the walls of its tongue-depressor-shaped burrow to extend an oblate hemispheroidal crack. Stress is concentrated at the crack tip, which extends when the stress intensity factor(KI) exceeds the critical stress intensity factor(KIc). Relevant forces were measured in gelatin, an analog for elastic muds, by photoelastic stress analysis, and were 0.015±0.001 N (mean ± s.d.; N=5). Measured elastic moduli (E) for gelatin and sediment were used in finite element models to convert the forces in gelatin to those required in muds to maintain the same body shapes observed in gelatin. The force increases directly with increasing sediment stiffness,and is 0.16 N for measured sediment stiffness of E=2.7×104 Pa. This measurement of forces exerted by burrowers is the first that explicitly considers the mechanical behavior of the sediment. Calculated stress intensity factors fall within the range of critical values for gelatin and exceed those for sediment, showing that crack propagation is a mechanically feasible mechanism of burrowing. The pharynx extends anteriorly as it everts, extending the crack tip only as far as the anterior of the worm, consistent with wedge-driven fracture and drawing obvious parallels between soft-bodied burrowers and more rigid, wedge-shaped burrowers (i.e. clams). Our results raise questions about the reputed high energetic cost of burrowing and emphasize the need for better understanding of sediment mechanics to quantify external energy expenditure during burrowing.
Automatic aeroelastic devices in the wings of a steppe eagleAquila nipalensis
Authors: Carruthers Anna C. , Thomas Adrian L. R. , Taylor Graham K. 
Published: November 2007

SUMMARYHere we analyse aeroelastic devices in the wings of a steppe eagle Aquila nipalensis during manoeuvres. Chaotic deflections of the upperwing coverts observed using video cameras carried by the bird (50 frames s–1) indicate trailing-edge separation but attached flow near the leading edge during flapping and gust response, and completely stalled flows upon landing. The underwing coverts deflect automatically along the leading edge at high angle of attack. We use high-speed digital video (500 frames s–1) to analyse these deflections in greater detail during perching sequences indoors and outdoors. Outdoor perching sequences usually follow a stereotyped three-phase sequence comprising a glide, pitch-up manoeuvre and deep stall. During deep stall, the spread-eagled bird has aerodynamics reminiscent of a cross-parachute. Deployment of the underwing coverts is closely phased with wing sweeping during the pitch-up manoeuvre,and is accompanied by alula protraction. Surprisingly, active alula protraction is preceded by passive peeling from its tip. Indoor flights follow a stereotyped flapping perching sequence, with deployment of the underwing coverts closely phased with alula protraction and the end of the downstroke. We propose that the underwing coverts operate as an automatic high-lift device, analogous to a Kruger flap. We suggest that the alula operates as a strake, promoting formation of a leading-edge vortex on the swept hand-wing when the arm-wing is completely stalled, and hypothesise that its active protraction is stimulated by its initial passive deflection. These aeroelastic devices appear to be used for flow control to enhance unsteady manoeuvres, and may also provide sensory feedback.
Olfactory sensitivity for putrefaction-associated thiols and indols in three species of non-human primate
Authors: Laska Matthias , Bautista Rosa Mariela Rivas , Höfelmann Daniela , Sterlemann Vera , Salazar Laura Teresa Hernandez 
Published: November 2007

SUMMARYUsing a conditioning paradigm, the olfactory sensitivity of four spider monkeys, three squirrel monkeys and three pigtail macaques to four thiols and two indols, substances characteristic of putrefaction processes and faecal odours, was assessed. With all odorants, the animals significantly discriminated concentrations below 1 p.p.m. (part per million) from the odourless solvent, and in several cases individual animals even demonstrated thresholds below 1 p.p.t. (part per trillion). The detection thresholds of 0.03 p.p.t. for indol in Saimiri sciureus and Macaca nemestrina and 0.96 p.p.t. for ethanethiol in Ateles geoffroyirepresent the lowest values among the more than 50 odorants tested so far with these species and are in the same order of magnitude as the lowest detection thresholds reported so far in the rat and the mouse. The results showed (a)all three species of non-human primate to have a highly developed olfactory sensitivity for putrefaction-associated odorants, and (b) a significant correlation between perceptibility in terms of olfactory detection threshold and carbon chain length of the thiols, and a marked effect of the presence vs absence of a methyl group on perceptibility of the indols tested in two of the three species. The results support the hypotheses that (a)between-species differences in neuroanatomical or genetic features may not be indicative of olfactory sensitivity, and (b) within-species differences in olfactory sensitivity may reflect differences in the behavioural relevance of odorants.
Poly(adp-ribose) Polymerase-1 Regulates Tracp Gene Promoter Activity During RANKL-Induced Osteoclastogenesis
Authors: Beranger Guillaume E , Momier David , Rochet Nathalie , Carle Georges F , Scimeca Jean-Claude 
Published: November 2007

Abstract
The Tracp gene encodes an acid phosphatase strongly upregulated during osteoclastogenesis on RANKL treatment. Using the mouse osteoclastic model RAW264.7, we studied Tracp gene expression, and we identified PARP-1 as a transcriptional repressor negatively regulated by RANKL during osteoclastogenesis.
Introduction: The Tracp gene encodes an acid phosphatase strongly expressed in differentiated osteoclasts. TRACP enzyme has a dual role and is involved in (1) the regulation of the biological activity of the bone matrix phosphoproteins osteopontin and bone sialoprotein and (2) the intracellular collagen degradation. Based on our previous work on Tcirg1 gene expression, and using data available in the literature, we focused on a 200-bp sequence located upstream the Tracp gene transcriptional start to identify binding activities.
Materials and Methods: We first performed siRNA transfections and RAW264.7 cell treatment with an inhibitor of poly(ADP-ribose) polymerase-1 (PARP-1) activity. After EMSA and supershift experiments, we measured the promoter activity of wildtype and mutant constructs throughout the osteoclastic differentiation.
Results: We first showed that depleting PARP-1 mRNA in the pre-osteoclastic cell line RAW264.7 results in an increase of both matrix metalloproteinase 9 and TRACP mRNA expression (3.5- and 2.5-fold, respectively). Moreover, in response to 3-aminobenzamide treatment, we measured a weak stimulation of MMP9 mRNA expression, whereas up to a 2-fold enhancement above the control condition of TRACP mRNA expression was observed. We next identified in the −839/−639 Tracp promoter region a PARP-1 binding site, and supershift experiments showed the interaction of a PARP-1 binding activity with the Tracp promoter sequence −830/−808. Finally, RAW264.7 cell transfection with a promoter construct mutated for this PARP-1 interacting sequence showed the functionality of this site within intact pre-osteoclastic cells.
Conclusions: In this study, we provide evidence that the transcriptional activity of the Tracp gene, in pre-osteoclastic cells, is negatively regulated by the binding of PARP-1 protein to a potential consensus sequence located in its promoter region. Taken together with our previous results related to the control of Tcirg1 gene expression, our data suggest that PARP-1 exerts a pivotal role in the basal repression of genes that are upregulated during RANKL-induced osteoclastogenesis.
Optimal Algorithmic Cooling of Spins
Authors: Elias Yuval , Fernandez José M. , Mor Tal , Weinstein Yossi 
Published: November 2007

AbstractAlgorithmic cooling (AC)is a recent spin‐cooling approach that employs entropy compression methods inopen systems. AC reduces the entropy of spins on suitable molecules beyond Shannon's bound on the degree of entropy compression by reversible manipulations. Remarkably, AC makes use of thermalization, a generally destructive facet of spin systems, as an integral part of the cooling scheme. AC is capable of cooling spins to very low temperatures and provides significant cooling for molecules containing as few as 5–7 spins. Application of AC to slightly larger molecules could lead to breakthroughs in high‐sensitivity NMR spectroscopy in the near future. Furthermore, AC may be germane to the development of scalable NMR quantum computers. We introduce here a new practicable algorithm, “PAC3”, and several new exhaustive cooling algorithms, such as the Tribonacci andk‐bonacci algorithms. In particular, we present the “all‐bonacci” algorithm, which appears to reach the maximal degree of cooling obtainable by the optimal AC approach. AC is potentially beneficial for NMR‐derived biomedical applications, which involve bio‐molecules with isotope enrichments, such as13C‐ and15N‐labeled amino acids. We briefly survey AC experiments, including a recent 3‐spin experiment in which Shannon's bound was bypassed. The difficulties associated with cooling molecules bearing a greater number of spins are explained. Finally, the potential of selected cooling algorithms (practicable, exhaustive, and optimal algorithms) is illustrated with regard to a highly relevant bio‐medical target—13C‐labeled glucose.
A novel approach in numerical simulation of contaminant removal by air sparging
Authors: Jacimovic N. , Hosoda T. , Ivetic M. , Kishida K. 
Published: November 2007

The paper presents a mechanistic/deterministic model for simulation of mass removal during air sparging. From the point of numerical modeling, there are two issues considering air sparging: modeling of air flow and distribution and modeling of mass transport and transfer. Several processes, which are commonly neglected, such as air channeling and pollutant advection by the water phase, are taken into account. The numerical model presented in this paper considers all relevant for mass transfer during the air sparging. Model includes hydrodynamics of air and water phase; calculated air volume content is divided into a number of air channels surrounded by the water phase, which is divided into two compartments. First compartment is immobile and it is in contact with air phase, while the second compartment is mobile. This “mobile-immobile” formulation is a common approach for description of solute transport by groundwater. Mass transfer between two water compartments is modeled as a first order kinetic, where the mass transfer coefficient, representing diffusion and advection in the water phase towards the air channels, is parameter needed to be calibrated. Sorption for both water compartments is considered.
The adopted model of contaminant evaporation at the air-water interface is verified by comparison with experimental results available from published sources. Model is used for simulation of two-dimensional air sparging laboratory experiment. Good overall agreement is observed. It is showed that the efficiency of air sparging can be influenced by natural groundwater flow.
Clinical characteristics and mode of inheritance of familial focal seizures in Standard Poodles
Authors: Licht Barbara G. , Lin Shili , Luo Yuqun , Hyson Linda L. , Licht Mark H. , Harper Kathleen M. , Sullivan Stacey A. , Fernandez Soledad A. , Johnston Eric V. 
Published: November 2007

Abstract
Objective—To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles.
Design—Case series.
Animals—90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures).
Procedures—Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data.
Results—Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance.
Conclusions and Clinical Relevance—Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age.
A follow-up study of neurologic and radiographic findings in working German Shepherd Dogs with and without degenerative lumbosacral stenosis
Authors: Steffen Frank , Hunold Katharina , Scharf Gernot , Roos Malgorzata , Flückiger Mark 
Published: November 2007

Abstract
Objective—To identify radiographic abnormalities associated with degenerative lumbosacral stenosis (DLSS) in German Shepherd Dogs (GSDs) and determine whether specific radiographic abnormalities could be used to identify dogs at risk of developing DLSS.
Design}Cohort study.
Animals—33 GSDs working as police dogs.
Procedures—Results of physical, neurologic, and orthopedic examinations were used to identify dogs with DLSS. Survey radiography of the lumbosacral junction was performed, and radiographs were compared with radiographs obtained 3 years earlier.
Results—DLSS was diagnosed in 15 of the 33 (45%) dogs. Thirteen of the 15 dogs with DLSS and 14 of the 18 dogs without DLSS had radiographic abnormalities of the lumbosacral junction. Twenty-two (67%) dogs were able to perform unrestricted duties, including 3 dogs with suspected DLSS. Six (18%) dogs had been excluded from active duty during the period of surveillance because of DLSS. Significant progression in specific clinical and radiographic signs was detected, but multiple logistic regression analysis did not identify any radiographic signs that could be used to predict the development of DLSS.
Conclusions and Clinical Relevance—Results suggested that survey radiography cannot be used to predict development of DLSS in working GSDs.
Evaluation of total and ionized calcium status in dogs with blastomycosis: 38 cases (1997–2006)
Authors: Crews Laura J. , Sharkey Leslie C. , Feeney Daniel A. , Jessen Carl R. , Ruska Tammy 
Published: November 2007

Abstract
Objective—To determine blood ionized calcium (iCa) and serum total calcium (tCa) concentrations in dogs with blastomycosis and to evaluate whether serum tCa concentration, albumin-adjusted serum calcium concentration (AdjCa-Alb), and total protein–adjusted serum calcium concentration (AdjCa-TP) accurately predict iCa status.
Design—Retrospective case series.
Animals—38 client-owned dogs with a cytologic diagnosis of blastomycosis.
Procedures—Dogs were classified as hypocalcemic, normocalcemic, or hypercalcemic on the basis of blood iCa concentration, serum tCa concentration, AdjCa-Alb, and AdjCa-TP; classification on the basis of serum tCa concentration, AdjCa-Alb, and AdjCa-TP was compared with blood iCa concentration.
Results—Except for 2 hypercalcemic dogs, all dogs had blood iCa concentrations within the reference interval. Use of serum tCa concentration overestimated hypocalcemia in 57.9% (22/38) of dogs and underestimated hypercalcemia in 1 dog. Use of AdjCa-Alb correctly reclassified all dogs as normocalcemic that were classified as hypocalcemic on the basis of serum tCa concentration, but failed to predict hypercalcemia in 1 dog. Use of AdjCa-TP correctly reclassified all but 2 dogs as normocalcemic that were classified as hypocalcemic on the basis of serum tCa concentration, and failed to predict hypercalcemia in 1 dog. No correlation was found between blood iCa concentration and serum concentrations of tCa, total protein, and albumin; AdjCa-Alb; or AdjCa-TP.
Conclusions and Clinical Relevance—High blood iCa concentration was uncommon in dogs with blastomycosis. Hypoalbuminemia contributed to a low serum tCa concentration despite a blood iCa concentration within reference limits. The use of serum tCa concentration, AdjCa-Alb, and AdjCa-TP may fail to identify a small number of dogs with high blood iCa concentrations.
An outbreak of cryptosporidiosis among alpaca crias and their human caregivers
Authors: Starkey Simon R. , Johnson Amy L. , Ziegler Peter E. , Mohammed Hussni O. 
Published: November 2007

Abstract
Case Description—6 alpaca crias from a single farm were examined because of diarrhea (n = 4) or decreased fecal production (n = 2).
Clinical Findings—Cryptosporidium parvum was identified by means of fecal flotation in samples from 5 of the 6 crias, and a diagnosis of cryptosporidiosis was made. In the remaining cria, a presumptive diagnosis of cryptosporidiosis was made. Three people involved in caring for the crias from this farm were subsequently confirmed to have cryptosporidiosis, and 3 other people were suspected to have cryptosporidiosis. Sequence analysis of the ssu rDNA gene loci confirmed C parvum as the causative agent in 4 of the 6 crias. Subsequent evaluation of the farm revealed 2 additional crias confirmed to have cryptosporidiosis. Stocking densities on the farm were high, with approximately 20 adults/acre in some pastures.
Treatment and Outcome—All 6 hospitalized crias were given supportive treatment consisting of antimicrobials, gastroprotectants, and fluids. All but 1 survived. Farm owners were advised to decrease stocking density on the farm.
Clinical Relevance—Findings suggested that zoonotic transmission of C parvum from alpacas to humans can occur.
Characterization of brainstem peptide YY (PYY) neurons
Authors: Glavas Maria M. , Grayson Bernadette E. , Allen Summer E. , Copp Daniel R. , Smith M. Susan , Cowley Michael A. , Grove Kevin L. 
Published: November 2007

AbstractPeptide YY (PYY), a member of the NPY superfamily of peptides, is predominantly synthesized by the colon and is thought to act on both the gut and brain to modulate energy homeostasis. Although neurons expressing PYY mRNA have also been reported in the brainstem, little is known about their physiological role and study of their projections has been problematic due to crossreactivity of PYY antibodies with NPY. In the present study we examined the localization of central PYY cell bodies in the mouse, rat, and monkey. In addition, efferent projections and afferent inputs of central PYY neurons were examined in rodents. Central PYY projections were examined by immunohistochemistry in the NPY knockout mouse, or with an NPY‐preabsorbed PYY antibody in the rat to avoid any crossreactivity with NPY. In all species investigated PYY‐immunoreactive (ir) cell bodies were localized exclusively to the gigantocellular reticular nucleus (Gi) of the rostral medulla. The highest density of PYY fibers was present within the solitary tract nucleus, specifically within the dorsal and lateral aspects. PYY fibers were also concentrated within the dorsal motor nucleus of the vagus and the hypoglossal nucleus. In addition, both orexin and melanin‐concentrating hormone fibers made numerous close appositions with PYY cell bodies in the Gi. Collectively, the projection pattern and association with orexigenic neuropeptides suggest that brainstem PYY neurons may play a role in energy homeostasis through a coordinated effect on visceral, motor, and sympathetic output targets. J. Comp. Neurol. 506:194–210, 2008. © 2007 Wiley‐Liss, Inc.
Origin of calretinin‐containing, vesicular glutamate transporter 2‐coexpressing fiber terminals in the entorhinal cortex of the rat
Authors: Wouterlood Floris G. , Aliane Verena , Boekel Amber J. , Hur Elizabeth E. , Zaborszky Laszlo , Barroso‐Chinea Pedro , Härtig Wolfgang , Lanciego José L. , Witter Menno P. 
Published: November 2007

AbstractThe entorhinal cortex of the rat (EC) contains a dense fiber plexus that expresses the calcium‐binding protein calretinin (CR). Some CR fibers contain vesicular glutamate transporter 2 (VGluT2, associated with glutamatergic neurotransmission). CR‐VGluT2 coexpressing fibers may have an extrinsic origin, for instance, the midline thalamic nucleus reuniens. Alternatively, they may belong to cortical interneurons. We studied the first possibility with anterograde and retrograde neuroanatomical tracing methods combined with CR and VGluT2 immunofluorescence and confocal laser scanning. The alternative possibility was studied with in situ hybridization fluorescence histochemistry for VGluT2 mRNA combined with CR immunofluorescence. In the anterograde tracing experiments, we observed many labeled reuniens fibers in EC expressing CR. Some of these labeled fibers contained immunoreactivity for VGluT2 and CR. In the complementary retrograde tracing experiments, we found retrogradely labeled cell bodies in nucleus reuniens of the thalamus that coexpressed CR. We also examined the colocalization of VGluT2 and CR in the entorhinal cortex by using in situ hybridization and CR immunofluorescence. In these experiments, we observed CR‐immunopositive cortical neurons that coexpressed VGluT2. For the same sections, with CR as the principal marker and parvalbumin as a control marker, we found that parvalbumin neurons were negative for VGluT2 mRNA. Thus, CR‐VGluT2‐expressing axon terminals in EC belong to two sources: projection fibers from the thalamus and axon collaterals of local interneurons. VGluT2 expression is linked to the synaptic transmission of the excitatory neurotransmitter glutamate, so these thalamic CR‐VGluT2 projection neurons and entorhinal CR‐VGluT2 interneurons should be regarded as excitatory. J. Comp. Neurol. 506:359–370, 2008. © 2007 Wiley‐Liss, Inc.
The relevance of the fetal and neonatal period for the development of novelty preferences, learning, habituation and hemispheric specialization
Authors: Turkewitz Gerald 
Published: November 2007

AbstractThe concept of instinct has been largely based on thinking which relies on an either or approach to determining the genesis of information required for the development of behavior patterns. In part, in response to criticisms of dichotomous views by Schneirla and Lehrman adherents of the view that there exist two distinct sources of information, that is, genetic or environmental (and all of the variants of this nomenclature including its most modern and currently popular form, that is, hard or soft wired) have modified their stance by positing that all characteristics are products of both. They therefore maintain that the task for analysis is parceling out the amount contributed by each source. Gottlieb's approach to an understanding of the development of various characteristics undercut this view by pointing out the inextricable relationship between the various components at all levels of organization. His view gives prenatal and early postnatal events particular relevance for explicating the intertwined nature of developmental processes. In this essay I will present suggestions from a variety of studies which explore and instantiate some of these complex relationships with regard to, novelty preferences, learning, habituation, and cognitive functioning and its' hemispheric specialization. I will also provide examples of how the unique characteristics of early stages of development promote particular types of epigenesis. © 2007 Wiley Periodicals, Inc. Dev Psychobiol 49: 780–787, 2007.