bluuebunny/crossref_metadata_2025 huggingface dataset:
Online Contributions of Auditory Feedback to Neural Activity in Avian Song Control Circuitry
Authors: Sakata Jon T. , Brainard Michael S.
Published: October 2008

Birdsong, like human speech, relies critically on auditory feedback to provide information about the quality of vocalizations. Although the importance of auditory feedback to vocal learning is well established, whether and how feedback signals influence vocal premotor circuitry has remained obscure. Previous studies in singing birds have not detected changes to vocal premotor activity after perturbations of auditory feedback, leading to the hypothesis that contributions of feedback to vocal plasticity might rely on“offline” processing. Here, we recorded single and multiunit activity in the premotor nucleus HVC (proper name) of singing Bengalese finches in response to feedback perturbations that are known to drive plastic changes in song. We found that transient feedback perturbation caused reliable decreases in HVC activity at short latencies (20–80 ms). Similar changes to HVC activity occurred in awake, nonsinging finches when the bird's own song was played back with auditory perturbations that simulated those experienced by singing birds. These data indicate that neurons in avian vocal premotor circuitry are rapidly influenced by perturbations of auditory feedback and support the possibility that feedback information in HVC contributes “online” to the production and plasticity of vocalizations.
Parietal Stimulation Decouples Spatial and Feature-Based Attention
Authors: Schenkluhn Bertram , Ruff Christian C. , Heinen Klaartje , Chambers Christopher D.
Published: October 2008

Everyday visual scenes contain a vast quantity of information, only a fraction of which can guide our behavior. Properties such as the location, color and orientation of stimuli help us extract relevant information from complex scenes (Treisman and Gelade, 1980; Livingstone and Hubel, 1987). But how does the brain coordinate the selection of such different stimulus characteristics? Neuroimaging studies have revealed significant regions of overlapping activity in frontoparietal cortex during attention to locations and features, suggesting a global component to visual selection (Vandenberghe et al., 2001; Corbetta and Shulman, 2002; Giesbrecht et al., 2003; Slagter et al., 2007). At the same time, the neural consequences of spatial and feature-based attention differ markedly in early visual areas (Treue and Martinez-Trujillo, 2007), implying that selection may rely on more specific top-down processes. Here we probed the balance between specialized and generalized control by interrupting preparatory attention in the human parietal cortex with transcranial magnetic stimulation (TMS). We found that stimulation of the supramarginal gyrus (SMG) impaired spatial attention only, whereas TMS of the anterior intraparietal sulcus (aIPS) disrupted spatial and feature-based attention. The selection of different stimulus characteristics is thus mediated by distinct top-down mechanisms, which can be decoupled by cortical interference.
Cell Death after Spinal Cord Injury Is Exacerbated by Rapid TNFα-Induced Trafficking of GluR2-Lacking AMPARs to the Plasma Membrane
Authors: Ferguson Adam R. , Christensen Randolph N. , Gensel John C. , Miller Brandon A. , Sun Fang , Beattie Eric C. , Bresnahan Jacqueline C. , Beattie Michael S.
Published: October 2008

Glutamate, the major excitatory neurotransmitter in the CNS, is implicated in both normal neurotransmission and excitotoxicity. Numerousin vitrofindings indicate that the ionotropic glutamate receptor, AMPAR, can rapidly traffic from intracellular stores to the plasma membrane, altering neuronal excitability. These receptor trafficking events are thought to be involved in CNS plasticity as well as learning and memory. AMPAR trafficking has recently been shown to be regulated by glial release of the proinflammatory cytokine tumor necrosis factor α (TNFα)in vitro. This has potential relevance to several CNS disorders, because many pathological states have a neuroinflammatory component involving TNFα. However, TNFα-induced trafficking of AMPARs has only been explored in primary or slice cultures and has not been demonstrated in preclinical models of CNS damage. Here, we use confocal and image analysis techniques to demonstrate that spinal cord injury (SCI) induces trafficking of AMPARs to the neuronal membrane. We then show that this effect is mimicked by nanoinjections of TNFα, which produces specific trafficking of GluR2-lacking receptors which enhance excitotoxicity. To determine if TNFα-induced trafficking affects neuronal cell death, we sequestered TNFα after SCI using a soluble TNFα receptor, and significantly reduced both AMPAR trafficking and neuronal excitotoxicity in the injury penumbra. The data provide the first evidence linking rapid TNFα-induced AMPAR trafficking to early excitotoxic secondary injury after CNS traumain vivo, and demonstrate a novel way in which pathological states hijack mechanisms involved in normal synaptic plasticity to produce cell death.
MAGI-1, A Candidate Stereociliary Scaffolding Protein, Associates with the Tip-Link Component Cadherin 23
Authors: Xu Zhigang , Peng Anthony W. , Oshima Kazuo , Heller Stefan
Published: October 2008

Inner ear hair-cell mechanoelectrical transduction is mediated by a largely unidentified multiprotein complex associated with the stereociliary tips of hair bundles. One identified component of tip links, which are the extracellular filamentous connectors implicated in gating the mechanoelectrical transduction channels, is the transmembrane protein cadherin 23 (Cdh23), more specifically, the hair- cell-specific Cdh23(+68) splice variant. Using the intracellular domain of Cdh23(+68) as bait, we identified in a cochlear cDNA library MAGI-1, a MAGUK (membrane-associated guanylate kinase) protein. MAGI-1 binds via its PDZ4 domain to a C-terminal PDZ-binding site on Cdh23. MAGI-1 immunoreactivity was detectable throughout neonatal stereocilia in a distribution similar to that of Cdh23. As development proceeded, MAGI-1 occurred in a punctate staining pattern on stereocilia, which was maintained into adulthood. Previous reports suggest that Cdh23 interacts via an internal PDZ-binding site with the PDZ1 domain of the stereociliary protein harmonin, and potentially via a weaker binding of its C terminus with harmonin's PDZ2 domain. We propose that MAGI-1 has the ability to replace harmonin's PDZ2 binding at Cdh23's C terminus. Moreover, the strong interaction between PDZ1 of harmonin and Cdh23 is interrupted by a 35 aa insertion in the hair-cell-specific Cdh23(+68) splice variant, which puts forward MAGI-1 as an attractive candidate for an intracellular scaffolding partner of this tip-link protein. Our results consequently support a role of MAGI-1 in the tip-link complex, where it could provide a sturdy connection with the cytoskeleton and with other components of the mechanoelectrical transduction complex.
Volumenstrommessung mit gravimetrischen Normalmessanlagen Flow Measurement with Gravimetric Weighing Systems
Authors: Mathies Nicolaus , Adunka Franz , Schupp Reiner
Published: October 2008

Die innerhalb definierter Messunsicherheiten liegende Volumenbestimmung strömender Medien in geschlossenen Rohrleitungen ist Abrechnungsgrundlage für eine Vielzahl von Anwendungsfällen. Steigende Kosten bei allen Produkten erheben den Anspruch an eine höhere Genauigkeit der eingesetzten Messgeräte und damit auch an die bei der Kalibrierung dieser Messgeräte zum Einsatz kommenden Messanlagen. Dies erfordert hierbei einerseits genaue Kenntnisse über Messanlage und Prüfverfahren, andererseits für die weltweite Vergleichbarkeit von Messdaten ein einheitliches Vorgehen bei der Messunsicherheitsanalyse. Im Folgenden werden aktuelle Prüfverfahren bei der Durchflussmessung sowie Mess- und Berechnungsverfahren für deren Eingangsgrößen vorgestellt und am Beispiel einer Messanlage erläutert.
Association of CD40 and thyroglobulin genes with later-onset Graves' disease in Taiwanese patients
Authors: Hsiao Jeng-Yueh , Hsieh Ming-Chia , Hsiao Cheng-Ting , Weng Hsu-Huei , Ke Der-Shin
Published: October 2008

Objective

Graves' disease (GD) is known to be associated with thyroglobulin (TG) and CD40 genes. Therefore, we decided to investigate the relationship of age at onset of GD with CD40 and TG gene susceptibilities in a Taiwanese population.

Design and method

We analyzed the association of TG and CD40 polymorphisms with age at onset of GD in Taiwanese patients. We stratified patients into those with early onset (<40 years; 30.3±4.8 years; n=135) and later onset (≥40 years; 52.3±6.3 years; n=80) and compared the results with those of 141 normal controls.

Results

We found a significant statistical difference in the T/T genotype frequency of E33 single nucleotide polymorphism (SNP) and G/G genotype frequency of E12 SNP when compared with the control group (P<0.001). In addition, the frequencies of the T allele and TT genotype of the CD40 SNP were found to be significantly increased in GD patients who developed GD aged over 40 years than those below 40 years (allele: χ2=5.299, P=0.021, OR=1.597; genotype: χ2=6.168, P=0.046). By contrast, the frequencies of genotypes in the TG gene E10, E12, and E33 SNPs were not found to be significantly different in GD patients who developed GD when aged over 40 years when compared with those aged below 40 years.

Conclusions

These data suggest that the T/T genotype and T allele in the CD40 gene are more likely to be associated with late-onset GD in Taiwanese patients.
Results of surgical and somatostatin analog therapies and their combination in acromegaly: a retrospective analysis of the German Acromegaly Register
Authors: Petersenn S , Buchfelder M , Reincke M , Strasburger C M , Franz H , Lohmann R , Quabbe H-J , Plöckinger U , _ _
Published: October 2008

Background

Data on surgical and medical treatment outcomes in acromegaly mostly originate from specialized centers. We retrospectively analyzed the data on surgery, primary somatostatin analog (SSA) therapy, surgery preceded by SSA, and SSA preceded by surgery in 1485 patients from the German Acromegaly Register.

Methods

Two trained nurses visited all centers (N=42) for data acquisition.

Results

Primary surgery: out of 889 patients, 554 yielded analyzable data (microadenomas 22.9%, macroadenomas 77.1%). GH and IGF1 normalized in 54.3 and 67.2%. Partial or total pituitary insufficiency occurred in 28.6% initially and 41.2% post-surgery. Primary SSA (≥3 months): out of 329 patients, 145 yielded analyzable data (microadenomas 26.7%, macroadenomas 73.3%). GH and IGF1 normalized in 36.3 and 30.5%, increasing to 40.8 and 41.5% with longer SSA (≥360 days) in 54 patients. Pituitary function did not change. SSA (≥3 months) prior to surgery: out of 234 patients, 93 yielded analyzable data. Post-surgery GH and IGF1 was normalized in 62.9 and 68.4%. GH improvement was slightly, but significantly better after SSA pretreatment. Surgery followed by SSA: out of 122 patients, 34 yielded analyzable data. GH and IGF1 normalized during SSA in 24.1 and 45.5%. Relative GH decrease was significantly larger compared with primary SSA.

Conclusions

Pituitary surgery was more effective to lower GH and IGF1 concentrations than primary SSA. Primary SSA may be an option in selected patients. SSA prior to surgery only marginally improved surgical outcome. Debulking surgery may result in better final outcome in patients with a high GH concentration and a large tumor.
A Specter of Coexistence: Is Centrifugal Community Organization Haunted by the Ghost of Competition?
Authors: Wasserberg Gideon , Kotler Burt P. , Morris Douglas W. , Abramsky Zvika
Published: October 2008

In a centrifugally organized community species prefer the same habitat (called “core”) but differ in their secondary habitat preferences. The first model of centrifugal community organization (CCO) predicted that optimally foraging, symmetrically competing species would share use of the core habitat at all density combinations. But one might also assume that the competition in the core habitat is asymmetrical, that is, that one of the species (the dominant) has a behavioral advantage therein. In this study, we asked how should habitat use evolve in a centrifugally organized community if its species compete asymmetrically in the core habitat? To address this question we developed an “isoleg model”. The model predicts that in a centrifugally organized community, asymmetric competition promotes the use of the core habitat exclusively by the dominant species at most points in the state space. The separation of the core habitat use by the species (“the ghost of competition past”) may be either complete or partial (“partial ghost”), and behavior at the stable competitive equilibrium between the species could determine whether coexistence should occur at the “complete-” or the “partial ghost” regions. This version of CCO should be a common feature of competitive systems.
Grazing Behavior of Lactating and Non-Lactating Yaks in the Summer Season of the Qinghai-Tibetan Plateau
Authors: Ding Luming , Long Ruijun , Wang Changting , Shang Zhanhuan
Published: October 2008

The effect of the physiological states of lactating vs. non-lactating (dry) on grazing behavior and herbage intake by yaks was examined in the summer season in the Qinghai alpine area under continuous stocking management. Intake rates were estimated over periods of 1 h by weighing the animals before and after grazing, retaining the feces and urine excreted, and applying a correction for insensible weight loss (the 1-h weight changes of yaks when non-eating before or after the intake rate measurement). It is hypothesized that the lactating yaks should eat more and spend more time eating than nonlactating yaks, because they expend more energy. In our experiment, there were no differences in the effect of physiological state (lactating vs. dry) of yaks observed on the rate of insensible weight loss, intake rate, grazing jaw movement rate, bites per grazing jaw movement, or bite mass. The dry yaks tended to eat more and spend more time eating than lactating yaks, but not significantly so. Compared with the dry yaks, the lactating yaks had a significantly lower bite rate and bites per bolus.
Has Simple Sequence Repeat Mutability Been Selected to Facilitate Evolution?
Authors: Kashia Yechezkel , King David G.
Published: October 2008

While adaptation and speciation begin with heritable variation, the underlying processes of mutation remain poorly understood. One particularly interesting source for prolific and adaptively meaningful variation is presented by the exceptionally high mutability of simple sequence repeats (SSRs: microsatellites and minisatellites). Frequent mutations at SSR sites alter the number of tandem repeats and create extensive polymorphism. Although most SSR variants are commonly presumed to be neutral, SSR variation has been shown to influence many biochemical, morphological, physiological, and behavioral characters, with at least a few examples offering evidence of response to selection. The type and degree of phenotypic variation depend upon each SSR's motif and on its location in exon, intron, or regulatory region, but the generation of abundant repeat-number variation is intrinsic to all of these repetitive sequences. Given the widespread distribution of SSRs within most genomes and their potential to modify almost any aspect of gene function, we believe that SSR mutability can facilitate evolutionary adaptation. Furthermore, we argue that the properties of SSRs allow natural selection to favor, indirectly, the mutability of these sites, in contrast to a conventional expectation that selection normally minimizes mutation rates by balancing the cost of deleterious mutations against the cost of replication fidelity. We believe that SSR mutability is not an "accident" of DNA replication, but has been adjusted and selected for this role. SSRs thus have a true biological function as general-purpose "tuning knobs" whereby mutations provide reversible adjustment for many quantitative and qualitative traits.
Aquatic Macrophyte Encroachment in Chinook Salmon Spawning Beds: Lessons Learned from Gravel Enhancement Monitoring in the Lower Mokelumne River, California
Authors: Merz Joseph E. , Smith James R. , Workman Michelle L. , Setka Jose D. , Mulchaey Bert
Published: October 2008

We studied the effects of colonization of the spawning habitat of Chinook salmon Oncorhynchus tshawytscha by rooted aquatic macrophytes in a regulated central California river. At least seven species of plants invaded four spawning sites below the lowest nonpassable dam during an extended period of relatively low instream flows. The depths associated with aquatic vegetation were similar to those used by spawning salmon. Velocities were significantly lower where plants took root. As plants expanded over riffles, spawning females avoided those areas. We observed significant overall reductions in vegetation after flow events predicted to be of sufficient magnitude to mobilize substrates. However, the proportion of vegetation dislodged did not strongly correlate with the proportion of substrate that we predicted would mobilize. Even so, in areas where vegetation was reduced, use by salmon spawning subsequently increased. While shear stress may be part of the overall predictive equation for macrophyte control at spawning sites, other factors must be studied before a specific management action can be recommended.
Influence of Patient Characteristics on Success of Ambulatory Blood Pressure Monitoring
Authors: Fravel Michelle A. , Ernst Michael E. , Weber Cynthia A. , Dawson Jeffrey D. , Carter Barry L. , Bergus George R.
Published: October 2008

Study Objective. To examine the influence of specific patient characteristics on the success of ambulatory blood pressure monitoring (ABPM).

Design. Retrospective analysis.

Setting. University‐affiliated family care center.

Patients. Five hundred thirty patients (mean age 52.7 yrs, range 14–90 yrs) who were undergoing ABPM between January 1, 2001, and July 1, 2007.

Measurement and Main Results. Specific patient characteristics were identified through an electronic medical record review and then examined for association with ABPM session success rate. These patient characteristics included age, sex, weight, height, body mass index (BMI), occupation, clinic blood pressure, travel distance to clinic, and presence of diabetes mellitus or renal disease. The percentage of valid readings obtained during an ABPM session was analyzed continuously (0–100%), whereas overall session success was analyzed dichotomously (0–79% or 80–100%). Univariate and multivariate regression analyses were performed to examine the influence of patient characteristics on the percentage of valid readings and the overall likelihood of achieving a successful session. In the 530 patients, the average percentage of valid readings was 90%, and a successful ABPM session (≥ 80% valid readings) was obtained in 84.7% (449 patients). A diagnosis of diabetes was found to negatively predict ABPM session success (continuous variable analysis, p=0.019; dichotomous variable analysis, odds ratio [OR] 0.45, 95% confidence interval [CI] 0.23‐0.87, p=0.019), as did renal disease (continuous variable analysis, p=0.006; dichotomous variable analysis, OR 0.39, 95% CI 0.17‐0.90, p=0.027) and increasing BMI (continuous variable analysis, p<0.001; dichotomous variable analysis, OR 0.78, 95% CI 0.65‐0.93, p=0.005). Renal disease and BMI remained significant predictors in adjusted analyses.

Conclusion. For most patients, ABPM was successful; however, elevated BMI and renal disease were associated with less complete ABPM session results. Adaptation and individualization of the ABPM process may be necessary to improve results in these patients.
Cardiac Arrest with Pulseless Electrical Activity Associated with Methylphenidate in an Adolescent with Normal Baseline Echocardiogram
Authors: Daly Michael W. , Custer Geoffrey , McLeay Peter D.
Published: October 2008

Recent concerns of adverse cardiac events associated with drugs used to treat attention‐deficit‐hyperactivity disorder (ADHD) have prompted debate over whether these drugs are truly safe. We describe a 17‐year‐old boy with a normal baseline echocardiogram who had been taking methylphenidate for ADHD for 18 months and experienced cardiac arrest. Emergency personnel attempted to resuscitate him, performing defibrillation twice for ventricular fibrillation, with subsequent pulseless electrical activity. The patient was immediately taken to the hospital where he received continued resuscitation, intravenous boluses of cardiac drugs, and additional defibrillation. A persistent pulsatile rhythm returned about 2 minutes after arrival. Overall, the patient was pulseless for 22 minutes. Emergency cardiac catheterization revealed wall motion abnormalities without coronary lesions. He was mechanically ventilated and was transferred to the intensive care unit, where he remained comatose. Neurologic studies performed the next day revealed diffuse encephalopathy due to anoxic brain injury. An echocardiogram on day 3 showed slightly improved left ventricular systolic function, which improved further by day 15. As the patient did not regain purposeful movement, he was discharged to a rehabilitation facility on day 33. The patient's methylphenidate therapy had been started at an appropriate dose of 18 mg/day and titrated over a period of 3 months up to 36 mg/day, which he continued until the event. The drug had been discontinued on admission, was not restarted, and for the next 2 years, the patient experienced no further cardiac events, although his severe mental deficiencies persisted. Use of the Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 6) between the patient's adverse cardiac event and methylphenidate. To our knowledge, this is the first case report of a patient with documentation of a normal baseline echocardiogram who experienced cardiac arrest with pulseless electrical activity while taking methylphenidate for ADHD. Clinicians should be aware that despite performing a comprehensive cardiac examination before prescribing a stimulant for ADHD, patients may still be at risk for a serious cardiac event. The risks and benefits of using these drugs must be assessed by clinicians, parents, and patients.
DermabondTM Tissue Adhesive Versus Steri-StripsTM in Unilateral Cleft Lip Repair: An Audit of Infection and Hypertrophic Scar Rates
Authors: Wilson Andrew D. H. , Mercer Nigel
Published: October 2008

Objective:

The purpose of this study was to compare the infection and hypertrophic scar rates in unilateral cleft lip repairs, having had Steri-Strips or Dermabond tissue glue applied across the repair as the final stage.

Design:

Retrospective study over 13 years of 307 unilateral cleft lip repairs by a single surgeon. The application of either Steri-Strips from 1992 to 1998 (121 patients) or Dermabond tissue adhesive from 1998 to 2006 (186 patients) was used in the final stage of the repair.

Setting:

Regional Centre for Cleft Lip and Palate Care, South West of England.

Participants:

307 consecutive unilateral cleft lip patients seen from 1992 to 2006.

Main Outcome Measures and Results:

There were five (4%) infections in the Steri-Strip group. All infections were with Staphylococcus aureus . No infections occurred in the Dermabond group (p < .001). There were 15 (12%) hypertrophic scars in the Steri-Strip group and 33 (18%) hypertrophic scars in the Dermabond group (p  =  .142). Revision surgery was required in a total of seven (6%) patients in the Steri-Strip group. No revisions were required in the Dermabond group (p. 1).

Conclusion:

We found a lower infection and revision rate and a similar hypertrophic scar rate when Dermabond was used instead of Steri-Strips in the final stage of unilateral cleft lip repair and suggest this study further supports the use of octyl-2-cyanoacrylate tissue adhesive in unilateral cleft lip repair.
How to find a dinosaur, and the role of synonymy in biodiversity studies
Authors: Benton Michael J.
Published: October 2008

Taxon discovery underlies many studies in evolutionary biology, including biodiversity and conservation biology. Synonymy has been recognized as an issue, and as many as 30–60% of named species later turn out to be invalid as a result of synonymy or other errors in taxonomic practice. This error level cannot be ignored, because users of taxon lists do not know whether their data sets are clean or riddled with erroneous taxa. A year-by-year study of a large clade, Dinosauria, comprising over 1000 taxa, reveals how systematists have worked. The group has been subject to heavy review and revision over the decades, and the error rate is about 40% at generic level and 50% at species level. The naming of new species and genera of dinosaurs is proportional to the number of people at work in the field. But the number ofvalidnew dinosaurian taxa depends mainly on the discovery of new territory, particularly new sedimentary basins, as well as the number of paleontologists. Error rates are highest (>50%) for dinosaurs from Europe; less well studied continents show lower totals of taxa, exponential discovery curves, and lower synonymy rates. The most prolific author of new dinosaur names was Othniel Marsh, who named 80 species, closely followed by Friedrich von Huene (71) and Edward Cope (64), but the “success rate” (proportion of dinosaurs named that are still regarded as valid) was low (0.14–0.29) for these earlier authors, and it appears to improve through time, partly a reflection of reduction in revision time, but mainly because modern workers base their new taxa on more complete specimens. If only 50% of species are valid, evolutionary biologists and conservationists must exercise care in their use of unrevised taxon lists.
Establishing a framework for archosaur cranial mechanics
Authors: Rayfield Emily J. , Milner Angela C.
Published: October 2008

The aim of this analysis was to establish the basic mechanical principles of simple archosaur cranial form. In particular we estimated the influence of two key archosaur innovations, the secondary palate and the antorbital fenestra, on the optimal resistance of biting-induced loads. Although such simplified models cannot substitute for more complex cranial geometries, they can act as a clearly derived benchmark that can serve as a reference point for future studies incorporating more complex geometry. We created finite element (FE) models comprising either a tall, domed (oreinirostral) snout or a broad, flat (platyrostral) archosaur snout. Peak von Mises stress was recorded in models with and without a secondary palate and/or antorbital fenestra after the application of bite loads to the tooth row. We examined bilateral bending and unilateral torsion-inducing bites for a series of bite positions along the jaw, and conducted a sensitivity analysis of material properties. Pairwise comparison between different FE morphotypes revealed that oreinirostral models are stronger than their platyrostral counterparts. Oreinirostral models are also stronger in bending than in torsion, whereas platyrostral models are equally susceptible to either load type. As expected, we found that models with a fenestra always have greatest peak stresses and by inference are “weaker,” significantly so in oreinirostral forms and anterior biting platyrostral forms. Surprisingly, although adding a palate always lowers peak stress, this is rarely by large magnitudes and is not significant in bilateral bending bites. The palate is more important in unilateral torsion-inducing biting. Two basic principles of archosaur cranial construction can be derived from these simple models: (1) forms with a fenestra are suboptimally constructed with respect to biting, and (2) the presence or absence of a palate is significant to cranial integrity in unilaterally biting animals. Extrapolating these results to archosaur cranial evolution, it appears that if mechanical optimization were the only criterion on which skull form is based, then most archosaurs could in theory strengthen their skulls to increase resistance to biting forces. These strengthened morphotypes are generally not observed in the fossil record, however, and therefore archosaurs appear subject to various non-mechanical morphological constraints. Carnivorous theropod dinosaurs, for example, may retain large suboptimal fenestra despite generating large bite forces, owing to an interplay between craniofacial ossification and pneumatization. Furthermore, living crocodylians appear to strengthen their skull with a palate and filled fenestral opening in the most efficient way possible, despite being constrained perhaps by hydrodynamic factors to the weaker platyrostral morphotype. The future challenge is to ascertain whether these simple predictions are maintained when the biomechanics of complex cranial geometries are explored in more detail.
Press-pulse: a general theory of mass extinction?
Authors: Arens Nan Crystal , West Ian D.
Published: October 2008

Previous discussions of mass extinction mechanisms generally focused on circumstances unique to each event. However, some have proposed that extensive volcanism combined with bolide impact may offer a general mechanism of mass extinction. To test this hypothesis we compared generic extinction percentages for 73 stages or substages of the Mesozoic and Cenozoic. We found that the highest frequency of intervals with elevated extinction occurred when continental flood basalt volcanism and bolide impact co-occurred. In contrast, neither volcanism nor impact alone yielded statistically elevated extinction frequencies. Although the magnitude of extinction was uncorrelated with the size of the associated flood basalt or impact structure, crater diameter did correlate with extinction percentage when volcanism and impact coincided. Despite this result, case-by-case analysis showed that the volcanism-impact hypothesis alone cannot explain all intervals of elevated extinction. Continental flood volcanism and impact share important ecological features with other proposed extinction mechanisms. Impacts, like marine anoxic incursions, are pulse disturbances that are sudden and catastrophic, and cause extensive mortality. Volcanism, like climate and sea level change, is a press disturbance that alters community composition by placing multi-generational stress on ecosystems. We propose that the coincidence of press and pulse events, not merely volcanism and impact, is required to produce the greatest episodes of dying in Phanerozoic history.
Hierarchy and the reconstruction of evolutionary trends: evidence for constraints on the evolution of body size in terrestrial caniform carnivorans (Mammalia)
Authors: Finarelli John A.
Published: October 2008

Body mass is an important organism-level variable in mammalian biology, correlated with physiology, life history, and ecology. To analyze the dynamics of body size evolution, increases and decreases in body mass were tallied for ancestor-descendant (AD) species pairs for 519 terrestrial caniform taxa. To account for uncertainty phylogeny, a bootstrapping routine shuffled hypothesized AD pairs, and average proportions of increases were binned as a function of ancestral body mass. A set of models relating the rate of body size increase were evaluated with the Akaike Information Criterion (AIC). AIC selected three models of the candidate set as equivalent in support by the observed body mass data. These three models propose body size increase for small AD pairs and body size decrease for large AD pairs, although they differ in their treatment of taxa at intermediate sizes.

These results demonstrate the presence of constraints bounding the caniform distribution at large and small body sizes, stabilizing the distribution through time, which stands in contrast to a broader mammalian pattern. At a finer phylogenetic scale, subclades within intermediate size classes display proportions that are significantly different from unbiased, with several clades previously cited as examples of “Cope's Rule” showing biased increases in size, and basal mustelids (badgers, and allied genera), Mephitidae (skunks), and Vulpini (“foxes”) exhibiting biased decreases. The caniform pattern is therefore the result of superimposed, clade-specific trajectories, demonstrating that the inferred dynamics of body size evolution and even the direction of trends in body size evolution within the Caniformia, and for mammals in general, depend on the hierarchical scale of the analysis.
Stable isotope evidence for changes in dietary niche partitioning among hadrosaurian and ceratopsian dinosaurs of the Hell Creek Formation, North Dakota
Authors: Fricke Henry C. , Pearson Dean A.
Published: October 2008

Questions related to dinosaur behavior can be difficult to answer conclusively by using morphological studies alone. As a complement to these approaches, carbon and oxygen isotope ratios of tooth enamel can provide insight into habitat and dietary preferences of herbivorous dinosaurs. This approach is based on the isotopic variability in plant material and in surface waters of the past, which is in turn reflected by carbon and oxygen isotope ratios of animals that ingested the organic matter or drank the water. Thus, it has the potential to identify and characterize dietary and habitat preferences for coexisting taxa.

In this study, stable isotope ratios from coexisting hadrosaurian and ceratopsian dinosaurs of the Hell Creek Formation of North Dakota are compared for four different stratigraphic levels. Isotopic offsets between tooth enamel and tooth dentine, as well as taxonomic differences in means and in patterns of isotopic data among taxa, indicate that primary paleoecological information is preserved. The existence of taxonomic offsets also provides the first direct evidence for dietary niche partitioning among these herbivorous dinosaur taxa. Of particular interest is the observation that the nature of this partitioning changes over time: for some localities ceratopsian dinosaurs have higher carbon and oxygen isotope ratios than hadrosaurs, indicating a preference for plants living in open settings near the coast, whereas for other localities isotope ratios are lower, indicating a preference for plants in the understory of forests. In most cases the isotope ratios among hadrosaurs are similar and are interpreted to represent a dietary preference for plants of the forest canopy. The inferred differences in ceratopsian behavior are suggested to represent a change in vegetation cover and hence habitat availability in response to sea level change or to the position of river distributaries. Given our current lack of taxonomic resolution, it is not possible to determine if dietary and habitat preferences inferred from stable isotope data are associated with single, or multiple, species of hadrosaurian/ceratopsian dinosaurs.
Developing unfired stabilised building materials in the UK
Authors: Oti J. E. , Kinuthia J. M. , Bai J.
Published: October 2008

This paper discusses laboratory tests on Lower Oxford Clay (LOC) stabilised using different levels of lime (L) or Portland cement (PC), with and without blending with ground granulated blast-furnace slag (GGBS). LOC is used by Hanson Brick Company Ltd in the manufacture of fired ‘London’ bricks at the Stewartby brick plant in Bedfordshire. The research investigated L-PC, L-GGBS and PC-GGBS blends to assess their potential for application in sustainable unfired clay building materials (bricks, mortar, etc.). Use of unfired materials reduces not only energy costs, but also environmental damage associated with the traditional firing process used in the manufacture of clay building components. Due to the high strength requirements of the building industry compared with, for example, stabilised highway pavement layers, a high maximum stabiliser dosage of 20% was used. For road construction, typical stabiliser dosages are 3–8% for lime and 3–5% for PC. In the current investigation, cylindrical test specimens were cured for 28 days at moisture contents of 25, 30, 35 and 40% before testing for unconfined compressive strength. Preliminary results show that the strength values for all stabilised material investigated was within the strength range of 737–2077 kN/m2 at 28 days, with L-PC blends tending to achieve lower strength values than L-GGBS blends. Overall results suggest that there is potential in using GGBS-based binders for the manufacture of unfired building components.
A Comparison of Field and Molecular Techniques for Sexing Beavers
Authors: CRAWFORD JOANNE C. , LIU ZHIWEI , NELSON THOMAS A. , NIELSEN CLAYTON K. , BLOOMQUIST CRAIG K.
Published: October 2008

Abstract: The traditional method of sex identification in beavers (Castor canadensis) by external palpation can be inaccurate. We tested 2 genetic methods for determining sex in beavers, the zinc‐finger DNA marker and the Y chromosome‐specific sex determining region (SRY) marker. The SRY marker identified sex correctly in 57 of 67 (85%) beavers, whereas the zinc‐finger technique was successful less often in only 48 of 67 (72%) animals. Sex was correctly assigned by palpation for 21 of 27 beavers (78%). Beaver studies in which accurate sex identification is critical may benefit by verifying the sex of individuals using one or both of these molecular markers.
Molecular Method for Determining Sex of Walruses
Authors: FISCHBACH ANTHONY S. , JAY CHADWICK V. , JACKSON JAMES V. , ANDERSEN LISELOTTE W. , SAGE GEORGE K. , TALBOT SANDRA L.
Published: October 2008

Abstract: We evaluated the ability of a set of published trans‐species molecular sexing primers and a set of walrus‐specific primers, which we developed, to accurately identify sex of 235 Pacific walruses (Odobenus rosmarus divergens). The trans‐species primers were developed for mammals and targeted the X‐ and Y‐gametologs of the zinc finger protein genes (ZFX, ZFY). We extended this method by using these primers to obtain sequence from Pacific and Atlantic walrus (O. r. rosmarus) ZFX and ZFY genes to develop new walrus‐specific primers, which yield polymerase chain reaction products of distinct lengths (327 and 288 base pairs from the X‐ and Y‐chromosome, respectively), allowing them to be used for sex determination. Both methods yielded a determination of sex in all but 1–2% of samples with an accuracy of 99.6–100%. Our walrus‐specific primers offer the advantage of small fragment size and facile application to automated electrophoresis and visualization.
Spatial and Temporal Analysis of Contact Rates in Female White‐Tailed Deer
Authors: KJÆR LENE J. , SCHAUBER ERIC M. , NIELSEN CLAYTON K.
Published: October 2008

Abstract: White‐tailed deer (Odocoileus virginianus) are important game mammals and potential reservoirs of diseases of domestic livestock; thus, diseases of deer are of great concern to wildlife managers. Contact, either direct or indirect, is necessary for disease transmission, but we know little about the ecological contexts that promote intrasexual contact among deer. Using pair‐wise direct contacts estimated from Global Positioning System collar locations and joint utilization distributions (JUDs), we assessed habitats in which contacts occur to test whether direct contact rates among female white‐tailed deer in different social groups differs among land‐cover types. We also tested whether contact rates differed among seasons, lunar phases, and times of day. We obtained locations from 27 female deer for periods of 0.5–17 months during 2002–2006. We designated any simultaneous pair of locations for 2 deer <25 m apart as a direct contact. For each season, we used compositional analysis to compare land‐cover types where 2 deer had contact to available land‐cover weighted by their JUD. We used mixed‐model logistic regression to test for effects of season, lunar phase, and time of day on contact rates. Contact rates during the gestation season were greater than expected from random use in forest and grassland cover, whereas contact rates during the fawning period were greater in agricultural fields than in other land‐cover types. Contact rates were greatest during the rut and lowest in summer. Diel patterns of contact rates varied with season, and contact rates were elevated during full moon compared to other lunar periods. Both spatial and temporal analyses suggest that contact between female deer in different social groups occurs mainly during feeding, which highlights the potential impact of food distribution and habitat on contact rates among deer. By using methods to associate contacts and land‐cover, we have created beneficial tools for more elaborate and detailed studies of disease transmission. Our methods can offer information necessary to develop spatially realistic models of disease transmission in deer.
Seasonal Altitudinal Movements of Mountain Goats
Authors: RICE CLIFFORD G.
Published: October 2008

Abstract:I investigated seasonal altitudinal movements of 42 mountain goats (Oreamnos americanus) in the Cascade Range of Washington, USA. Because mountain goats typically move to lower elevations during the winter, I partitioned locations from Global Positioning System collars into summer and winter seasons based on elevation. Using an iterative narrowing search, I identified summer and winter start dates for each individual and year and derived several measures of altitudinal movements from these, and examined differences in these measures on the basis of sex and year and their interrelationship. Generally, female mountain goats started summer about 2 weeks earlier than nondispersing males; winter start dates varied among years. Horizontal distance moved between seasons was unrelated to measures of altitudinal movement. Based on elevation, winters were generally longer than summers for mountain goats I studied, suggesting that the common perception of mountain goats as inhabitants of alpine and subalpine terrain is biased, because they spent the greater part of the year at lower elevations. Mountain goats showed a wide range of responses to seasonal environmental changes and individuals cannot be easily classified as migratory or nonmigratory. Because ecological conditions in mountain environments are closely related to elevation and horizontal and altitudinal movements were unrelated, studies of seasonal movements of mountain animals based on horizontal movement may be misleading. Because seasonal altitudinal movements of mountain goats are highly variable, the management needs of each population must be considered separately.
Statistical Ritual Versus Knowledge Accrual in Wildlife Science
Authors: GUTHERY FRED S.
Published: October 2008

Abstract: I hypothesized that statistical ritual has supplanted knowledge accrual as the sine qua non of wildlife science. Under the hypothesis, I deduced occurrence of 1) significance testing of the obvious and inconsequential, 2) quantitative debasement of research problems, and 3) publication of papers that largely lacked information but were methodologically impeccable. Articles in past and recent wildlife literature fit the deductions and supported the hypothesis. Thus, wildlife science is operating inefficiently because quantitative formalities are supplanting ecological information in technical articles. This problem can be corrected by a change of mindset in authors, referees, and editors. The change entails less emphasis on quantitative ritual and more emphasis on information that aids in understanding and explaining nature and managing wildlife.
Recovery of Chlorine from Anhydrous Hydrogen Chloride
Authors: Reddy Usha Virendra , Cheedipudi Vijaya Lakshmi , Bankupalli Satyavathi , Kotra Viswanath
Published: October 2008

Chlorine and hydrogen chloride are classified as potentially hazardous and toxic chemicals. Large-scale industrial processes worldwide use chlorine as primary raw material from which hydrogen chloride is obtained as a major byproduct. Hydrogen chloride is sold as aqueous HCl or used as a raw material for the production of chlorinated products, but the quantity of HCl produced by chlorine processes is much more than what the market can absorb, resulting in a toxic waste disposal problem. Recovery of material chlorine from this hydrogen chloride is very important and is of utmost industrial interest as it would cut down on the production of chlorine at the same time solve the waste disposal problem. It is theoretically possible to convert hydrogen chloride to chlorine for the recycling and reuse of chlorine. In this paper we have developed a process for recovery of chlorine from anhydrous hydrogen chloride obtained as a byproduct during low temperature vapor phase hydrolysis of titanium chloride to get TiO2. It is a two-stage process where chlorination is carried out in a fixed bed reactor using copper oxide catalyst at a temperature in the range of 423-523 K followed by oxidation of copper chloride catalyst in a second fixed bed reactor operating at 573-653 K. This process operates under conditions in which the catalyst does not volatilize and in which the activity of the catalyst remains stable. Operation at relatively moderate temperature prevents corrosion and minimizes the extrinsic energy input required. The chlorine recovery process makes the new generation chloride process for synthesis of TiO2 economical.
Love on the Rocks: Domestic Violence and Alcohol Abuse in Rural Mexico
Authors: Angelucci Manuela
Published: October 2008

I use experimental data for the evaluation of Oportunidades to study the determinants of domestic violence and alcohol abuse. The program, a combination of cash transfers to women and human capital investments, decreases husbands' alcohol abuse by 15% and changes their aggressive behavior depending on transfer size, husbands' education, and spousal age gap. While small transfers decrease violence by 37% for all households, large transfers increase the aggressive behavior of husbands with traditional views of gender roles, probably because their wife's entitlement to a large transfer threatens their identity. This evidence rejects standard unitary, collective, and bargaining models for this latter group of households. It also shows that, while targeting women as recipients of micro-credit or other welfare programs may have additional beneficial effects by reducing alcoholism and domestic violence in most households, the risk of violence may increase for some.
One-Year Comparison of a High–Monounsaturated Fat Diet With a High-Carbohydrate Diet in Type 2 Diabetes
Authors: Brehm Bonnie J. , Lattin Barbara L. , Summer Suzanne S. , Boback Jane A. , Gilchrist Gina M. , Jandacek Ronald J. , D’Alessio David A.
Published: October 2008

OBJECTIVE—The purpose of this study was to compare the effects of high–monounsaturated fatty acid (MUFA) and high-carbohydrate (CHO) diets on body weight and glycemic control in men and women with type 2 diabetes.

RESEARCH DESIGN AND METHODS—Overweight/obese participants with type 2 diabetes (n = 124, age = 56.5 ± 0.8 years, BMI = 35.9 ± 0.3 kg/m2, and A1C = 7.3 ± 0.1%) were randomly assigned to 1 year of a high-MUFA or high-CHO diet. Anthropometric and metabolic parameters were assessed at baseline and after 4, 8, and 12 months of dieting.

RESULTS—Baseline characteristics were similar between the treatment groups. The overall retention rate for 1 year was 77% (69% for the high-MUFA group and 84% for the high-CHO group; P = 0.06). Based on food records, both groups had similar energy intake but a significant difference in MUFA intake. Both groups had similar weight loss over 1 year (−4.0 ± 0.8 vs. −3.8 ± 0.6 kg) and comparable improvement in body fat, waist circumference, diastolic blood pressure, HDL cholesterol, A1C, and fasting glucose and insulin. There were no differences in these parameters between the groups. A follow-up assessment of a subset of participants (n = 36) was conducted 18 months after completion of the 52-week diet. These participants maintained their weight loss and A1C during the follow-up period.

CONCLUSIONS—In individuals with type 2 diabetes, high-MUFA diets are an alternative to conventional lower-fat, high-CHO diets with comparable beneficial effects on body weight, body composition, cardiovascular risk factors, and glycemic control.