bluuebunny/crossref_metadata_2025 huggingface dataset:
SELF-PROPELLED INTERACTING PARTICLE SYSTEMS WITH ROOSTING FORCE
Authors: CARRILLO JOSÉ A. , KLAR AXEL , MARTIN STEPHAN , TIWARI SUDARSHAN
Published: June 2010

We consider a self-propelled interacting particle system for the collective behavior of swarms of animals, and extend it with an attraction term called roosting force, as it has been suggested in Ref. 30. This new force models the tendency of birds to overfly a fixed preferred location, e.g. a nest or a food source. We include roosting to the existing individual-based model and consider the associated mean-field and hydrodynamic equations. The resulting equations are investigated analytically looking at different asymptotic limits of the corresponding stochastic model. In addition to existing patterns like single mills, the inclusion of roosting yields new scenarios of collective behavior, which we study numerically on the microscopic as well as on the hydrodynamic level.
STABILITY BY HOMOGENIZATION OF THERMOVISCOPLASTIC PROBLEMS
Authors: CHARALAMBAKIS NICOLAS , MURAT FRANCOIS
Published: June 2010

In this paper, we study the homogenization of the system of partial differential equations describing the quasistatic shearing of heterogeneous thermoviscoplastic materials. We first present the existence and uniqueness of the solution of the above system. We then define "stable by homogenization" models as the models where the equations in both the heterogeneous problems and the homogenized one are of the same form. Finally we show that the model with non-oscillating strain-rate sensitivity which is submitted to steady boundary shearing and body force, is stable by homogenization. In this model, the homogenized (effective) coefficients depend on the initial conditions and on the boundary shearing and body force. Those theoretical results are illustrated by one numerical example.
NUMERICAL ANALYSIS OF COSSERAT ROD AND STRING MODELS FOR VISCOUS JETS IN ROTATIONAL SPINNING PROCESSES
Authors: ARNE WALTER , MARHEINEKE NICOLE , MEISTER ANDREAS , WEGENER RAIMUND
Published: June 2010

This work deals with the curling behavior of slender viscous jets in rotational spinning processes. In terms of slender-body theory, an instationary incompressible viscous Cosserat rod model is formulated which differs from the approach of Ribe et al.,18 in the incompressibility approximation and reduces to the string model of Marheineke and Wegener13 for a vanishing slenderness parameter. Focusing exclusively on viscous and rotational effects on the jet in the exit plane near the spinning nozzle, the stationary two-dimensional scenario is described by a two-point boundary value problem of a system of first-order ordinary differential equations for jet's center-line, tangent, curvature, velocity, inner shear and traction force and couple. The numerical analysis shows that the rod model covers the string model in an inertia-dominated jet regime. Beyond that it overcomes the limitations of the string model studied by Götz et al.10 and enables even the handling of the viscous-inertial jet regime. Thus, the rod model shows its applicability for the simulation of industrially relevant parameter ranges and enlarges the domain of validity with respect to the string approach.
Designating 'Learning Days' Sends the Wrong Message
Authors: Little Bob
Published: June 2010

Designating a day, or even a week, as special to adult learning or learning at work gives the distinct impression to those who aren't "learning professionals" that learning can -- or, worse still, should -- only take place at that time.
Herding Chats
Authors: Rutherford LeAne H.
Published: June 2010

Lessons learned from a synchronous online interaction.
Attention, Intention, and Priority in the Parietal Lobe
Authors: Bisley James W. , Goldberg Michael E.
Published: June 2010

For many years there has been a debate about the role of the parietal lobe in the generation of behavior. Does it generate movement plans (intention) or choose objects in the environment for further processing? To answer this, we focus on the lateral intraparietal area (LIP), an area that has been shown to play independent roles in target selection for saccades and the generation of visual attention. Based on results from a variety of tasks, we propose that LIP acts as a priority map in which objects are represented by activity proportional to their behavioral priority. We present evidence to show that the priority map combines bottom-up inputs like a rapid visual response with an array of top-down signals like a saccade plan. The spatial location representing the peak of the map is used by the oculomotor system to target saccades and by the visual system to guide visual attention.
Connecting Vascular and Nervous System Development: Angiogenesis and the Blood-Brain Barrier
Authors: Tam Stephen J. , Watts Ryan J.
Published: June 2010

The vascular and nervous systems share a common necessity of circuit formation to coordinate nutrient and information transfer, respectively. Shared developmental principles have evolved to orchestrate the formation of both the vascular and the nervous systems. This evolution is highlighted by the identification of specific guidance cues that direct both systems to their target tissues. In addition to sharing cellular and molecular signaling events during development, the vascular and nervous systems also form an intricate interface within the central nervous system called the neurovascular unit. Understanding how the neurovascular unit develops and functions, and more specifically how the blood-brain barrier within this unit is established, is of utmost importance. We explore the history, recent discoveries, and unanswered questions surrounding the relationship between the vascular and nervous systems with a focus on developmental signaling cues that guide network formation and establish the interface between these two systems.
Molecular Pathways of Frontotemporal Lobar Degeneration
Authors: Sleegers Kristel , Cruts Marc , Van Broeckhoven Christine
Published: June 2010

Frontotemporal lobar degeneration (FTLD) is a neurodegenerative condition that predominantly affects behavior, social awareness, and language. It is characterized by extensive heterogeneity at the clinical, pathological, and genetic levels. Recognition of these levels of heterogeneity is important for proper disease management. The identification of progranulin and TDP-43 as key proteins in a significant proportion of FTLD patients has provided the impetus for a wealth of studies probing their role in neurodegeneration. This review highlights the most recent developments and future directions in this field and puts them in perspective of the novel insights into the neurodegenerative process, which have been gained from related disorders, e.g., the role of FUS in amyotrophic lateral sclerosis.
How Does Neuroscience Affect Our Conception of Volition?
Authors: Roskies Adina L.
Published: June 2010

Although there is no clear concept of volition or the will, we do have intuitive ideas that characterize the will, agency, and voluntary behavior. Here I review results from a number of strands of neuroscientific research that bear upon our intuitive notions of the will. These neuroscientific results provide some insight into the neural circuits mediating behaviors that we identify as related to will and volition. Although some researchers contend that neuroscience will undermine our views about free will, to date no results have succeeded in fundamentally disrupting our commonsensical beliefs. Still, the picture emerging from neuroscience does raise new questions, and ultimately may put pressure on some intuitive notions about what is necessary for free will.
Mechanisms of Synapse and Dendrite Maintenance and Their Disruption in Psychiatric and Neurodegenerative Disorders
Authors: Lin Yu-Chih , Koleske Anthony J.
Published: June 2010

Emerging evidence indicates that once established, synapses and dendrites can be maintained for long periods, if not for the organism's entire lifetime. In contrast to the wealth of knowledge regarding axon, dendrite, and synapse development, we understand comparatively little about the cellular and molecular mechanisms that enable long-term synapse and dendrite maintenance. Here, we review how the actin cytoskeleton and its regulators, adhesion receptors, and scaffolding proteins mediate synapse and dendrite maintenance. We examine how these mechanisms are reinforced by trophic signals passed between the pre- and postsynaptic compartments. We also discuss how synapse and dendrite maintenance mechanisms are compromised in psychiatric and neurodegenerative disorders.
Molecular and Cellular Mechanisms of Learning Disabilities: A Focus on NF1
Authors: Shilyansky C. , Lee Y.S. , Silva A.J.
Published: June 2010

Neurofibromatosis Type I (NF1) is a single-gene disorder characterized by a high incidence of complex cognitive symptoms, including learning disabilities, attention deficit disorder, executive function deficits, and motor coordination problems. Because the underlying genetic cause of this disorder is known, study of NF1 from a molecular, cellular, and systems perspective has provided mechanistic insights into the etiology of higher-order cognitive symptoms associated with the disease. In particular, studies of animal models of NF1 indicated that disruption of Ras regulation of inhibitory networks is critical to the etiology of cognitive deficits associated with NF1. Animal models of Nf1 identified mechanisms and pathways that are required for cognition, and represent an important complement to the complex neuropsychological literature on learning disabilities associated with this condition. Here, we review findings from NF1 animal models and human populations affected by NF1, highlighting areas of potential translation and discussing the implications and limitations of generalizing findings from this single-gene disease to idiopathic learning disabilities.
Watching Synaptogenesis in the Adult Brain
Authors: Kelsch Wolfgang , Sim Shuyin , Lois Carlos
Published: June 2010

Although the lifelong addition of new neurons to the olfactory bulb and dentate gyrus of mammalian brains is by now an accepted fact, the function of adult-generated neurons still largely remains a mystery. The ability of new neurons to form synapses with preexisting neurons without disrupting circuit function is central to the hypothesized role of adult neurogenesis as a substrate for learning and memory. With the development of several new genetic labeling and imaging techniques, the study of synapse development and integration of these new neurons into mature circuits both in vitro and in vivo is rapidly advancing our insight into their structural plasticity. Investigators' observation of synaptogenesis occurring in the adult brain is beginning to shed light on the flexibility that adult neurogenesis offers to mature circuits and the potential contribution of the transient plasticity that new neurons provide toward circuit refinement and adaptation to changing environmental demands.
Fungi, Hidden in Soil or Up in the Air: Light Makes a Difference
Authors: Rodriguez-Romero Julio , Hedtke Maren , Kastner Christian , Müller Sylvia , Fischer Reinhard
Published: June 2010

Light is one of the most important environmental factors for orientation of almost all organisms on Earth. Whereas light sensing is of crucial importance in plants to optimize light-dependent energy conservation, in nonphotosynthetic organisms, the synchronization of biological clocks to the length of a day is an important function. Filamentous fungi may use the light signal as an indicator for the exposure of hyphae to air and adapt their physiology to this situation or induce morphogenetic pathways. Although a yes/no decision appears to be sufficient for the light-sensing function in fungi, most species apply a number of different, wavelength-specific receptors. The core of all receptor types is a chromophore, a low-molecular-weight organic molecule, such as flavin, retinal, or linear tetrapyrrols for blue-, green-, or red-light sensing, respectively. Whereas the blue-light response in fungi is one of the best-studied light responses, all other light-sensing mechanisms are less well studied or largely unknown. The discovery of phytochrome in bacteria and fungi in recent years not only advanced the scientific field significantly, but also had great impact on our view of the evolution of phytochrome-like photoreceptors.
How to Make a Living by Exhaling Methane
Authors: Ferry James G.
Published: June 2010

Methane produced in the biosphere is derived from two major pathways. Conversion of the methyl group of acetate to CH4 in the aceticlastic pathway accounts for at least two-thirds, and reduction of CO2 with electrons derived from H2, formate, or CO accounts for approximately one-third. Although both pathways have terminal steps in common, they diverge considerably in the initial steps and energy conservation mechanisms. Steps and enzymes unique to the CO2 reduction pathway are confined to methanogens and the domain Archaea. On the other hand, steps and enzymes unique to the aceticlastic pathway are widely distributed in the domain Bacteria, the understanding of which has contributed to a broader understanding of prokaryotic biology.
Use of Fluorescence Microscopy to Study Intracellular Signaling in Bacteria
Authors: Kentner David , Sourjik Victor
Published: June 2010

Following the introduction of fluorescent protein tags, the application of fluorescence microscopy in microbial cell biology has advanced the field dramatically. We now understand that bacterial cells are not simple bags of enzymes but have complex internal structures, and that specific intracellular organization plays an important role in a number of processes, including signal transduction. The quantitative nature and high temporal resolution of fluorescence microscopy make it particularly useful for studies of intracellular dynamic systems, such as signaling networks. Applications of fluorescence microscopy in signaling are not limited to studying localization. Several techniques allow researchers to follow real-time dynamics of protein interactions, at steady state or upon stimulation, and therefore to investigate signal propagation, amplification, and integration in the cell. Moreover, microscopy enables investigation of single-cell gene expression kinetics, bringing such concepts as cell individuality and robustness against stochasticity of gene expression to the forefront of signaling studies.
Iron-Oxidizing Bacteria: An Environmental and Genomic Perspective
Authors: Emerson David , Fleming Emily J. , McBeth Joyce M.
Published: June 2010

In the 1830s, iron bacteria were among the first groups of microbes to be recognized for carrying out a fundamental geological process, namely the oxidation of iron. Due to lingering questions about their metabolism, coupled with difficulties in culturing important community members, studies of Fe-oxidizing bacteria (FeOB) have lagged behind those of other important microbial lithotrophic metabolisms. Recently, research on lithotrophic, oxygen-dependent FeOB that grow at circumneutral pH has accelerated. This work is driven by several factors including the recognition by both microbiologists and geoscientists of the role FeOB play in the biogeochemistry of iron and other elements. The isolation of new strains of obligate FeOB allowed a better understanding of their physiology and phylogeny and the realization that FeOB are abundant at certain deep-sea hydrothermal vents. These ancient microorganisms offer new opportunities to learn about fundamental biological processes that can be of practical importance.
Signaling Mechanisms of HAMP Domains in Chemoreceptors and Sensor Kinases
Authors: Parkinson John S.
Published: June 2010

HAMP domains mediate input-output signaling in histidine kinases, adenylyl cyclases, methyl-accepting chemotaxis proteins, and some phosphatases. HAMP subunits have two 16-residue amphiphilic helices (AS1, AS2) joined by a 14- to 15-residue connector segment. Two alternative HAMP structures in these homodimeric signaling proteins have been described: HAMP(A), a tightly packed, parallel, four-helix bundle; and HAMP(B), a more loosely packed bundle with an altered AS2/AS2′ packing arrangement. Stimulus-induced conformational changes probably modulate HAMP signaling by shifting the relative stabilities of these opposing structural states. Changes in AS2/AS2′ packing, in turn, modulate output signals by altering structural interactions between output helices through heptad repeat stutters that produce packing phase clashes. Output helices that are too tightly or too loosely packed most likely produce kinase-off output states, whereas kinase-on states require an intermediate range of HAMP stabilities and dynamic behaviors. A three-state, dynamic bundle signaling model best accounts for the signaling properties of chemoreceptor mutants and may apply to other transducers as well.
Mycobacteriophages: Genes and Genomes
Authors: Hatfull Graham F.
Published: June 2010

Viruses are powerful tools for investigating and manipulating their hosts, but the enormous size and amazing genetic diversity of the bacteriophage population have emerged as something of a surprise. In light of the evident importance of mycobacteria to human health—especially Mycobacterium tuberculosis, which causes tuberculosis—and the difficulties that have plagued their genetic manipulation, mycobacteriophages are especially appealing subjects for discovery, genomic characterization, and manipulation. With more than 70 complete genome sequences available, the mycobacteriophages have provided a wealth of information on the diversity of phages that infect a common bacterial host, revealed the pervasively mosaic nature of phage genome architectures, and identified a huge number of genes of unknown function. Mycobacteriophages have provided key tools for tuberculosis genetics, and new methods for simple construction of mycobacteriophage recombinants will facilitate postgenomic explorations into mycobacteriophage biology.
Conversations with a Psychiatrist
Authors: Ornston L. Nicholas
Published: June 2010

This reminiscence is a celebration of my good fortune in family, biological and scientific. The biological family into which I was born gave me a strong start, although not entirely in the direction I took. I swerved from an anticipated career in medical practice into continuing delight in those who became my scientific family in microbiology. The families changed, yet they continued to give me strength and inspiration. In my youth, I was gently guided by mentors who gave me freedom to explore where curiosity beckoned. I hope I repaid this gift to my laboratory colleagues who enlightened me over the years. I learned much from my students, and my horizons were extended by industrial scientists. It has been my particular good fortune to learn the workings of microorganisms and microbiologists as editor of Journal of Bacteriology for a decade, as editor-in-chief of Applied and Environmental Microbiology for a decade, and as editor of Annual Review of Microbiology for a quarter of a century.
Stealth and Opportunism: Alternative Lifestyles of Species in the Fungal GenusPneumocystis
Authors: Cushion Melanie T. , Stringer James R.
Published: June 2010

Pneumocystis species are ascomycetous fungi that obligatorily dwell with no apparent ill effect in the lungs of normal mammals, but they become pathogenic when host defenses are compromised. Identified more than 100 years ago, these atypical fungi manifest characteristics that are unique within the Fungi, such as the lack of ergosterol, genetic complexity of surface antigens, and antigenic variation. Thought to be confined to the severely immunocompromised host, Pneumocystis spp. are being associated with new population niches owing to the advent of immunomodulatory therapies and increased numbers of patients suffering from chronic diseases. The inability to grow Pneumocystis spp. outside the mammalian lung has thwarted progress toward understanding their basic biology, but via the use of new genetic tools and other strategies, researchers are beginning to uncover their biological and genetic characteristics including a biphasic life cycle, significant metabolic capacities, and modulation of lifestyles.
DNA Viruses: The Really Big Ones (Giruses)
Authors: Van Etten James L. , Lane Leslie C. , Dunigan David D.
Published: June 2010

Viruses with genomes greater than 300 kb and up to 1200 kb are being discovered with increasing frequency. These large viruses (often called giruses) can encode up to 900 proteins and also many tRNAs. Consequently, these viruses have more protein-encoding genes than many bacteria, and the concept of small particle/small genome that once defined viruses is no longer valid. Giruses infect bacteria and animals although most of the recently discovered ones infect protists. Thus, genome gigantism is not restricted to a specific host or phylogenetic clade. To date, most of the giruses are associated with aqueous environments. Many of these large viruses (phycodnaviruses and Mimiviruses) probably have a common evolutionary ancestor with the poxviruses, iridoviruses, asfarviruses, ascoviruses, and a recently discovered Marseillevirus. One issue that is perhaps not appreciated by the microbiology community is that large viruses, even ones classified in the same family, can differ significantly in morphology, lifestyle, and genome structure. This review focuses on some of these differences than on extensive details about individual viruses.
Emotion, Cognition, and Mental State Representation in Amygdala and Prefrontal Cortex
Authors: Salzman C. Daniel , Fusi Stefano
Published: June 2010

Neuroscientists have often described cognition and emotion as separable processes implemented by different regions of the brain, such as the amygdala for emotion and the prefrontal cortex for cognition. In this framework, functional interactions between the amygdala and prefrontal cortex mediate emotional influences on cognitive processes such as decision-making, as well as the cognitive regulation of emotion. However, neurons in these structures often have entangled representations, whereby single neurons encode multiple cognitive and emotional variables. Here we review studies using anatomical, lesion, and neurophysiological approaches to investigate the representation and utilization of cognitive and emotional parameters. We propose that these mental state parameters are inextricably linked and represented in dynamic neural networks composed of interconnected prefrontal and limbic brain structures. Future theoretical and experimental work is required to understand how these mental state representations form and how shifts between mental states occur, a critical feature of adaptive cognitive and emotional behavior.
Genetics and Cell Biology of Building Specific Synaptic Connectivity
Authors: Shen Kang , Scheiffele Peter
Published: June 2010

The assembly of specific synaptic connections during development of the nervous system represents a remarkable example of cellular recognition and differentiation. Neurons employ several different cellular signaling strategies to solve this puzzle, which successively limit unwanted interactions and reduce the number of direct recognition events that are required to result in a specific connectivity pattern. Specificity mechanisms include the action of contact-mediated and long-range signals that support or inhibit synapse formation, which can take place directly between synaptic partners or with transient partners and transient cell populations. The molecular signals that drive the synaptic differentiation process at individual synapses in the central nervous system are similarly diverse and act through multiple, parallel differentiation pathways. This molecular complexity balances the need for central circuits to be assembled with high accuracy during development while retaining plasticity for local and dynamic regulation.
Category Learning in the Brain
Authors: Seger Carol A. , Miller Earl K.
Published: June 2010

The ability to group items and events into functional categories is a fundamental characteristic of sophisticated thought. It is subserved by plasticity in many neural systems, including neocortical regions (sensory, prefrontal, parietal, and motor cortex), the medial temporal lobe, the basal ganglia, and midbrain dopaminergic systems. These systems interact during category learning. Corticostriatal loops may mediate recursive, bootstrapping interactions between fast reward-gated plasticity in the basal ganglia and slow reward-shaded plasticity in the cortex. This can provide a balance between acquisition of details of experiences and generalization across them. Interactions between the corticostriatal loops can integrate perceptual, response, and feedback-related aspects of the task and mediate the shift from novice to skilled performance. The basal ganglia and medial temporal lobe interact competitively or cooperatively, depending on the demands of the learning task.
Disparate effects of feeding on core body and adipose tissue temperatures in animals selectively bred for Nervous or Calm temperament
Authors: Henry Belinda A. , Blache Dominique , Rao Alexandra , Clarke Iain J. , Maloney Shane K.
Published: June 2010

In addition to homeostatic regulation of body mass, nonhomeostatic factors impact on energy balance. Herein we describe effects of temperament on adipose and core body temperatures in sheep. Animals were genetically selected for Nervous or Calm traits. We characterized the effects of 1) high- and low-energy intake and maintenance feeding, 2) meal anticipation, and 3) adrenocorticotropin challenge on core body and adipose temperatures. Temperature measurements (5 min) were made using a thermistor inserted into the carotid artery (core body) and a probe in the retroperitoneal fat. An imposed feeding window was used to establish postprandial elevations in temperature. Fat tissue was taken from retroperitoneal and subcutaneous regions for real-time PCR analyses. We demonstrate that innate differences in temperament impact on adipose and core body temperatures in response to various dietary and evocative stimuli. In response to homeostatic cues (low-energy intake and maintenance feeding) core body temperature tended to be higher in Calm compared with Nervous animals. In contrast, in response to nonhomeostatic cues, Nervous animals had higher anticipatory thermogenic responses than Calm animals. Expression of uncoupling protein (UCP)-1 and -2 mRNA were higher in retroperitoneal tissue than in subcutaneous tissue, but UCP3 and leptin mRNA levels were similar at both sites; expression of these genes was similar in Nervous and Calm animals. There were no differences in stress responsiveness. We conclude that temperament differentially influences adipose thermogenesis and the regulation of core body temperature in responses to both homeostatic and nonhomeostatic stimuli.
Electrophysiological and Chemical Properties in Subclassified Acutely Dissociated Cells of Rat Trigeminal Ganglion by Current Signatures
Authors: Xu Shenghong , Ono Kentaro , Inenaga Kiyotoshi
Published: June 2010

In the present study, we subclassified acutely dissociated trigeminal ganglion (TRG) cells of rats using a current signature method in whole cell patch-clamp recordings. Using modified criteria for cell classification for the dorsal root ganglion (DRG), TRG cells were subclassified into nine cell types: 1–5, 7–9, and 13. Types 1, 3, and 7 were in the small cell groups (15–24 μm); types 4, 5, and 8–13 were in the medium cell groups (25–38 μm); and type 2 was a mixed group of both cell sizes. Types 1–3, 5, and 7 showed high-input resistance and types 1, 2, and 7 showed more depolarized resting membrane potentials. Types 1, 2, and 5–13 expressed long-duration action potentials (APs), but types 3 and 4 expressed short-duration APs. Sensitivities to capsaicin, protons, and adenosine 5′-triphosphate (ATP) in TRG cell types largely corresponded to DRG cell types. However, different from the matched DRG types, half of TRG type 1 cells were capsaicin insensitive, showing desensitizing proton-induced currents, and types 5, 7, and 9 exhibited slow-desensitizing ATP-induced currents. Types 4, 5, and 8–13 had nicotine sensitivity, but the other cell types were insensitive. These results indicate that the “current signatures” classification is a useful means to separate TRG cells into internally homogeneous subpopulations that were distinct from other cell types. Furthermore, the data suggest some specific differences in the chemical responsiveness of some cell types between the TRG and DRG.
Transcriptome profiling in response to adiponectin in human cancer-derived cells
Authors: Berger Emmanuelle , Rome Sophie , Vega Nathalie , Ciancia Claire , Vidal Hubert
Published: June 2010

The adipocyte-derived hormone adiponectin exerts protective actions in several disorders, including some cancers. However, while growing data suggest that adiponectin could be an effective anticancer agent, its mechanism of action in cancer cells is still poorly known. Here, using microarrays, we identified a set of 1,301 genes commonly modulated in three cancer-derived cell lines in response to short-term stimulation with full-length recombinant human adiponectin. Most of these genes are involved in translation regulation, immune or stress responses, and cell proliferation. Furthermore, among genes linked to disease that were retrieved by functional enrichment tests using text mining based on PubMed analysis, we found that 66% are involved in malignant neoplasms, further supporting the link between adiponectin and cancer mechanisms. Bioinformatic analysis demonstrated the diversity of signaling pathways and transcription factors potentially mediating adiponectin effects on gene expression, illustrating the complexity of adiponectin mechanisms of action in cancer cells.
Confirmation of multiple seizure susceptibility QTLs on chromosome 15 in C57BL/6J and DBA/2J inbred mice
Authors: Ferraro T. N. , Smith G. G. , Schwebel C. L. , Doyle G. A. , Ruiz S. E. , Oleynick J. U. , Lohoff F. W. , Berrettini W. H. , Buono R. J.
Published: June 2010

To confirm seizure susceptibility (SZS) quantitative trait loci (QTLs) on chromosome (chr) 15 identified previously using C57BL/6J (B6) and DBA/2J (D2) mice and to refine their genomic map position, we studied a set of three congenic strains in which overlapping segments of chr 15 from D2 were transferred onto the B6 background. We measured thresholds for generalized electroshock seizure (GEST) and maximal electroshock seizure (MEST) in congenic strains and B6-like littermates and also tested their responses to kainic acid (KA) and pentylenetetrazol (PTZ). Results document that MEST is significantly lower in strains 15M and 15D, which harbor medial and distal (telomeric) segments of chr 15 (respectively) from D2, compared with strain 15P, which harbors the proximal (acromeric) segment of chr 15 from D2, and with control littermates. Congenic strains 15P and 15M exhibited greater KA SZS compared with strain 15D and B6-like controls. All congenic strains were similar to controls with regard to PTZ SZS. Taken together, results suggest there are multiple SZS QTLs on chr 15 and that two QTLs harbor gene variants that affect MEST and KA SZS independently. The MEST QTL is refined to a 19 Mb region flanked by rs13482630 and D15Mit159. This interval contains 350 genes, 183 of which reside in areas where the polymorphism rate between B6 and D2 is high. The KA QTL interval spans a 65 Mb region flanked by markers D15Mit13 and rs31271969. It harbors 83 genes in highly polymorphic areas, 310 genes in all. Complete dissection of these loci will lead to identification of genetic variants that influence SZS in mice and provide a better understanding of seizure biology.
Decompressive Abdominal Laparotomy for Abdominal Compartment Syndrome in an Unengrafted Bone Marrow Recipient with Septic Shock
Authors: Dauplaise Derrick J. N. , Barnett Sean J. , Frischer Jason S. , Wong Hector R.
Published: June 2010

Objective. To describe a profoundly immunocompromised (panleukopenia) child with septic shock who developed abdominal compartment syndrome (ACS) and was successfully treated with surgical decompression.Design. Individual case report.Setting. Pediatric intensive care unit of a tertiary children's hospital.Patient. A 32-month-old male with Fanconi anemia who underwent bone marrow transplantation (BMT) 5 days prior to developing septic shock secondary toStreptococcus viridansandEscherichia coliACS developed after massive fluid resuscitation, leading to cardiopulmonary instability.Interventions. Emergent surgical bedside laparotomy and silo placement.Measurements and Main Results. The patient's cardiopulmonary status stabilized after decompressive laparotomy. The abdomen was closed and the patient survived to hospital discharge without cardiac, respiratory, or renal dysfunction.Conclusions. The use of laparotomy and silo placement in an unengrafted BMT patient with ACS and septic shock did not result in additional complications. Surgical intervention for ACS is a reasonable option for high risk, profoundly immunocompromised patients.
Instantons, Topological Strings, and Enumerative Geometry
Authors: Szabo Richard J.
Published: June 2010

We review and elaborate on certain aspects of the connections between instanton counting in
maximally supersymmetric gauge theories and the computation of enumerative invariants of
smooth varieties. We study in detail three instances of gauge theories in six, four, and two
dimensions which naturally arise in the context of topological string theory on certain noncompact
threefolds. We describe how the instanton counting in these gauge theories is related
to the computation of the entropy of supersymmetric black holes and how these results are
related to wall‐crossing properties of enumerative invariants such as Donaldson‐Thomas and
Gromov‐Witten invariants. Some features of moduli spaces of torsion‐free sheaves and the
computation of their Euler characteristics are also elucidated.
Direct Microbicidal Activity of Cytotoxic T-Lymphocytes
Authors: Oykhman Paul , Mody Christopher H.
Published: June 2010

Cytotoxic T-lymphocytes (CTL) are famous for their ability to kill tumor, allogeneic and virus-infected cells. However, an emerging literature has now demonstrated that CTL also possess the ability to directly recognize and kill bacteria, parasites, and fungi. Here, we review past and recent findings demonstrating the direct microbicidal activity of bothCD4+andCD8+CTL against various microbial pathogens. Further, this review will outline what is known regarding the mechanisms of direct killing and their underlying signalling pathways.
Ocean Emission Effects on Aerosol‐Cloud Interactions: Insights from Two Case Studies
Authors: Sorooshian Armin , Duong Hanh T.
Published: June 2010

Two case studies are discussed that evaluate the effect of ocean emissions on aerosol‐cloud interactions. A review of the first case study from the eastern Pacific Ocean shows that simultaneous aircraft and space‐borne observations are valuable in detecting links between ocean biota emissions and marine aerosols, but that the effect of the former on cloud microphysics is less clear owing to interference from background anthropogenic pollution and the difficulty with field experiments in obtaining a wide range of aerosol conditions to robustly quantify ocean effects on aerosol‐cloud interactions. To address these limitations, a second case was investigated using remote sensing data over the less polluted Southern Ocean region. The results indicate that cloud drop size is reduced more for a fixed increase in aerosol particles during periods of higher ocean chlorophyll A. Potential biases in the results owing to statistical issues in the data analysis are discussed.
Screening for Group B Streptococcus: A Private Hospital's Experience
Authors: Faro Sebastian , Brehm Brenda , Smith Frances , Mouzoon Melanie , Greisinger Anthony , Wehmanen Oscar , Turrentine Mark A.
Published: June 2010

Objective. To assess the effect of universal screening and administration of intrapartum antibiotic prophylaxis to prevent early-onset neonatal GBS sepsis at a private tertiary care hospital since issuance of the 2002 CDC guidelines for preventing perinatal GBS disease.Methods. Retrospective analysis of women delivering between January 1, 2003 and December 31, 2004 at a private tertiary care hospital in Houston, Texas. The percentage of women screened, GBS positive women receiving intrapartum antibiotic prophylaxis, and infants developing early-onset GBS sepsis were determined.Results. 2,108 women delivered 2,135 infants with 1,874 (89%) screened for GBS. Of those screened, 1,322 (71%) tested negative and 552 (29%) tested positive for GBS. In this analysis of 2,135 infants, 3 (0.94 cases/1,000 live births) were diagnosed with invasive GBS sepsis.Conclusion. High rates of screening of pregnant women for GBS colonization and use of intrapartum antibiotic prophylaxis for GBS carriers can be achieved in a private tertiary care hospital setting. “Synopsis: High screening rates for group B streptococcus in a private tertiary care hospital reduce the incidence of maternal and early onset neonatal GBS infection.”
Lyme Neuroborreliosis: Preliminary Results from an Urban Referral Center Employing Strict CDC Criteria for Case Selection
Authors: Younger David S. , Orsher Stuart
Published: June 2010

Lyme neuroborreliosis or “neurological Lyme disease” was evidenced in 2 of 23 patients submitted to strict criteria for case selection of the Centers for Disease Control and Prevention employing a two-tier test to detect antibodies toBorrelia burgdorferiat a single institution. One patient had symptomatic polyradiculoneuritis, dysautonomia, and serological evidence of early infection; and another had symptomatic small fiber sensory neuropathy, distal polyneuropathy, dysautonomia, and serological evidence of late infection. In the remaining patients symptoms initially ascribed to Lyme disease were probably unrelated toB. burgdorferiinfection. Our findings suggest early susceptibility and protracted involvement of the nervous system most likely due to the immunological effects ofB. burgdorferiinfection, although the exact mechanisms remain uncertain.
Indications and Early Outcomes for Total Pancreatectomy at a High-Volume Pancreas Center
Authors: Janot Monika S. , Belyaev Orlin , Kersting Sabine , Chromik Ansgar M. , Seelig Matthias H. , Sülberg Dominique , Mittelkötter Ulrich , Uhl Waldemar H.
Published: June 2010

Background. This study aimed to analyse the most common current indications for total pancreatectomy (TP) at a high-volume pancreas center. Method. Prospectively collected data on indications and short-term outcome of all TP's performed from January 2004 until June 2008 were analysed. Results. The total pancreatectomies (TP) were 63, i.e., 6.7% of all pancreatic procedures (). Indications for TP were classified into 4 groups: tumors of advanced stage, (36.5%), technical problems due to soft pancreatic tissue, (28.6%), troubles due to perioperative surgical complications, (23.8%), and therapy-resistant pain due to chronic pancreatitis, (11.1%). Surgical complications occurred in 23 patients (36.5%). The mortality in elective TP was 6.25%. Median postoperative stay was 21 days. Mortality, morbidity and the other perioperative parameters differed substantially according to the indication for pancreatectomy. Conclusion. Total pancreatectomy is definitely indicated for a limited range of elective and emergency situations. Indications can be: size or localisation of pancreatic tumor, trouble, technical diffuculties and therapy-refractory pain in chronic pancreatitis. A TP due to perioperative complications (troubles) after pancreatic resections is doomed by extremely high morbidity and mortality and should be avoided.
Effect of Birth Weight and Socioeconomic Status on Children's Growth in Mashhad, Iran
Authors: Mohammadzadeh Ashraf , Farhat Ahmadshah , Amiri Rana , Esmaeeli Habibollah
Published: June 2010

Background. Socioeconomic status and birth weight are prominent factors for future growing of children. Also Studies show that this criterion is associated with reduced cognitive outcomes, school achievement, and adult work capacity. So in this paper we determined the effects of some socio-economic statuses and birth weight on physical growth of children in Mashhad, Iran.Method and materials. This is a cross sectional study that determined effect of socio-economic status and birth weight on weight, heighting and BMI of school age children. Healthy six years old children who were screened before enter, to school were eligible for participating in our study between 6 June 2006 and 31 July. Weight and standing height were documented at birth and measured at 6 years old. Then, their BMI were calculated in childhood period. Data were analyzed by using SPSS software.Result. Results show that some socio-economic variables and birth weight is associated with and, perhaps, influence the variation of growth in the children. The variables which show the most consistent and significant association were birth weight, sex, economic status and education of parents.Conclusion. In this paper, we found that birth weight, economic status and education parents of neonates have directly significant effect on growth childhood period. We recommended that paying attention to these criteria for improving growth of children in our society should be considered by authorities.
Digital Image Reconstruction in the Spectral Domain Utilizing the Moore‐Penrose Inverse
Authors: Chountasis Spiros , Katsikis Vasilios N. , Pappas Dimitrios
Published: June 2010

The field of image restoration has seen a tremendous growth in interest over the last two decades. The recovery of an original image from degraded observations is a crucial method and finds application in several scientific areas including medical imaging and diagnosis, military surveillance, satellite and astronomical imaging, and remote sensing. The proposed approach presented in this work employs Fourier coefficients for moment‐based image analysis. The main contributions of the presented technique, are that the image is first analyzed in orthogonal basis matrix formulation increasing the selectivity on image components, and then transmitted in the spectral domain. After the transmission has taken place, at the receiving end the image is transformed back and reconstructed from a set of its geometrical moments. The calculation of the Moore‐Penrose inverse ofr×mmatrices provides the computation framework of the method. The method has been tested by reconstructing an image represented by anr×mmatrix after the removal of blur caused by uniform linear motions. The noise during the transmission process is another issue that is considered in the current work.
Instability of Financial Markets and Preference Heterogeneity
Authors: Franke Günter , Lüders Erik
Published: June 2010

This paper presents a simple rational expectations model of intertemporal asset pricing relating instability of stock return characteristics to heterogeneity in investor preferences. Heterogeneity is likely to generate declining aggregate relative risk aversion. This leads to variability in expected asset returns, volatility, and autocorrelation. The stronger this variability is, the more heterogeneous preferences are, implying more instability of financial markets. Stock market crashes may be observed if relative risk aversion differs strongly across investors.
Determination of X‐Ray Diffraction on the Phase Transformation of Microwave‐Assisted Titanate Nanotubes during Thermal Treatment
Authors: Ou Hsin-Hung , Liao Ching-Hui , Lo Shang-Lien
Published: June 2010

Based on the determination of X‐ray powder diffraction, this study aims to investigate the thermal effect on the phase transformation of microwave‐assisted titanate nanotubes (MTNTs). The phase transformation is highly dependent on the intercalating amount of Na(I) within MTNTs and on the heating atmosphere. In other words, the presence of Na(I) favors the transformation of TNTs phase into Na2Ti6O13 whereas anatase phase selectively formed in the case of MTNTs with less Na(I) amount. Furthermore, H2 versus O2 is able to form anatase phase and establish a newly transformation pathway. The photocatalytic ability of the calcined MTNTs was also evaluated based on the observed rate constant of trichloroethylene degradation. In addition to anatase phase, the newly phase including Na2Ti6O13 and Ti2O3 with calcined MTNTs is able to photocatalyze trichloroethylene. MTNTs calcined with the presence of H2 also exhibit a superior photocatalytic performance to P25 TiO2.
In Search for Titanocene Complexes with Improved Cytotoxic Activity: Synthesis, X‐Ray Structure, and Spectroscopic Study of Bis(η5‐cyclopentadienyl)difluorotitanium(IV)
Authors: Koleros Elias , Stamatatos Theocharis C. , Psycharis Vassilis , Raptopoulou Catherine P. , Perlepes Spyros P. , Klouras Nikolaos
Published: June 2010

The 1 : 2 reaction of and AgF in CHCl3/H2O yielded the fluoro analog (1) in almost quantitative yield (C5H5 is the cyclopentadienyl group). The coordination about the TiIV atom formed by two fluoro ligands and the centroids of the cyclopentadienyl rings is distorted tetrahedral. The compound crystallizes in the orthorhombic space group C2cm. The lattice constants are a = 5.9055(4), b = 10.3021(5), c = 14.2619(9) Å, and α = β = γ = 90°. The complex has been characterized by elemental analyses and spectroscopic (IR,  1H NMR) data. A structural comparison of the four members of the family of complexes (X = F, Cl, Br, I) is attempted.
Metastatic Growth from Dormant Cells Induced by a Col-I–Enriched Fibrotic Environment
Authors: Barkan Dalit , El Touny Lara H. , Michalowski Aleksandra M. , Smith Jane Ann , Chu Isabel , Davis Anne Sally , Webster Joshua D. , Hoover Shelley , Simpson R. Mark , Gauldie Jack , Green Jeffrey E.
Published: June 2010

Breast cancer that recurs as metastatic disease many years after primary tumor resection and adjuvant therapy seems to arise from tumor cells that disseminated early in the course of disease but did not develop into clinically apparent lesions. These long-term surviving, disseminated tumor cells maintain a state of dormancy, but may be triggered to proliferate through largely unknown factors. We now show that the induction of fibrosis, associated with deposition of type I collagen (Col-I) in the in vivo metastatic microenvironment, induces dormant D2.0R cells to form proliferative metastatic lesions through β1-integrin signaling. In vitro studies using a three-dimensional culture system modeling dormancy showed that Col-I induces quiescent D2.0R cells to proliferate through β1-integrin activation of SRC and focal adhesion kinase, leading to extracellular signal-regulated kinase (ERK)–dependent myosin light chain phosphorylation by myosin light chain kinase and actin stress fiber formation. Blocking β1-integrin, Src, ERK, or myosin light chain kinase by short hairpin RNA or pharmacologic approaches inhibited Col-I–induced activation of this signaling cascade, cytoskeletal reorganization, and proliferation. These findings show that fibrosis with Col-I enrichment at the metastatic site may be a critical determinant of cytoskeletal reorganization in dormant tumor cells, leading to their transition from dormancy to metastatic growth. Thus, inhibiting Col-I production, its interaction with β1-integrin, and downstream signaling of β1-integrin may be important strategies for preventing or treating recurrent metastatic disease. Cancer Res; 70(14); 5706–16. ©2010 AACR.