cssi/SciSciGPT-SciSciNet huggingface dataset:
A Learning Framework for Controlling Spiking Neural Networks

Controlling a population of interconnected neurons using extrinsic stimulation is a challenging problem. The challenges are due to the inherent nonlinear neuronal dynamics, the highly complex structure of underlying neuronal networks, the underactuated nature of the control problem, and adding to these is the binary nature of the observation/feedback. To meet these challenges, adaptive, learning-based approaches using deep neural networks and reinforcement learning are potentially useful strategies. In this paper, we propose an approximation based learning framework in which a model for approximating the input-output relationship in a spiking neuron is developed. We then present a reinforcement learning scheme to approximate the solution for the Bellman equation, and to design the control sequence to achieve a desired spike pattern. The proposed strategy, by integrating the reinforcement learning and system theoretic approaches, provides a tractable framework to design a learning control network, and to select the hyper parameters in deep learning architectures. We demonstrate the feasibility of the proposed approach using numerical simulations.
Making a Tough Call: Medical Neglect in Terminally Ill Children

Introduction: Failure to fulfill unmet medical needs of a child raises substantial concern for medical neglect. Mandatory reporting laws govern that medical providers report suspicion for neglect to Child Protective Services (CPS). Criteria for reporting neglect among terminally ill children remain vague and largely unstudied. In this unique population, self-directive care goals center predominantly around comfort measures, forgoing aggressive medical intervention, and enhancing end-stage quality of life. Providers’ perceptions around utility of CPS involvement with families of dying children may influence reporting decisions. When …
Un evento sin testigos: memoria y trauma en Las reputaciones de Juan Gabriel Vásquez

Las reputaciones (2013), by Juan Gabriel Vasquez, narrates the sexual abuse of a girl. Unlike some critics, this essay highlights the centrality of this child abuse and other intertextual elements as essential for the understanding of the novel. Based on studies on trauma and memory, I argue that this event of child abuse is a traumatic one without witnesses because of the girl's inability to witness to herself, her fragmented memories, and the silence surrounding the event. Thus, Las reputaciones invites a profound reflection on things forgotten, trauma, memory, and silence.
Particle transport and deposition correlation with near-wall flow characteristic under inspiratory airflow in lung airways.

Abstract Exposure of lung airways to detrimental suspended aerosols in the environment increases the vulnerability of the respiratory and cardiovascular systems. In addition, recent developments in therapeutic inhalation devices magnify the importance of particle transport. In this manuscript, particle transport and deposition patterns in the upper tracheobronchial (TB) tree were studied where the inertial forces are considerable for microparticles. Wall shear stress divergence (WSSdiv) is proposed as a wall-based parameter that can predict particle deposition patterns. WSSdiv is proportional to near-wall normal velocity and can quantify the strength of flow towards and away from the wall. Computational fluid dynamics (CFD) simulations were performed to quantify airflow velocity and WSS vectors for steady inhalation in one case-control and unsteady inhalation in six subject-specific airway trees. Turbulent flow simulation was performed for the steady case using large eddy simulation to study the effect of turbulence. Magnetic resonance velocimetry (MRV) measurements were used to validate the case-control CFD simulation. Inertial particle transport was modeled by solving the Maxey–Riley equation in a Lagrangian framework. Deposition percentage (DP) was quantified for the case-control model over five particle sizes. DP was found to be proportional to particle size in agreement with previous studies in the literature. A normalized deposition concentration (DC) was defined to characterize localized deposition. A relatively strong correlation (Pearson value > 0.7) was found between DC and positive WSSdiv for physiologically relevant Stokes ( S t ) numbers. Additionally, a regional analysis was performed after dividing the lungs into smaller areas. A spatial integral of positive WSSdiv over each division was shown to maintain a very strong correlation (Pearson value > 0.9) with cumulative spatial DC or regional dosimetry. The conclusions were generalized to a larger population in which two healthy and four asthmatic patients were investigated. This study shows that WSSdiv could be used to predict the qualitative surface deposition and relative regional dosimetry without the need to solve a particle transport problem.
Pembrolizumab: An Immunotherapeutic Agent Causing Endocrinopathies

Pembrolizumab is an immune checkpoint inhibitor (programmed cell death 1) approved for use in non-small cell lung carcinoma (NSCLC). Pembrolizumab has shown remarkable results in regression of the size of tumors in NSCLC and has shown survival advantage. However, immune-related adverse effects are a serious negative outcome of therapy. The number of immune-related adverse effects with pembrolizumab has increased significantly over the recent past. We present a case of type 1 diabetes mellitus and autoimmune thyroiditis with pembrolizumab treatment for NSCLC.
Interesting paths in the mapper complex.

Given a high dimensional point cloud of data with functions defined on the points, the mapper algorithm produces a compact summary in the form of a simplicial complex connecting the points. This summary offers insightful data visualizations, which have been employed in applications to identify subsets of points, i.e., subpopulations, with interesting properties. These subpopulations typically appear as long paths, flares (i.e., branching paths), or loops in the mapper complex.We study the problem of quantifying the interestingness of subpopulations in a given mapper complex. First, we create a weighted directed graph G=(V,E) using the 1-skeleton of the mapper complex. We use the average values at the vertices (i.e., clusters) of the target function (i.e., a dependent variable) to direct the edges from low to high values. We set the difference between the average values at the vertices (high-low) as the weight of the edge. Covariation of the remaining h functions (i.e., independent variables) is captured by a h-bit binary signature assigned to the edge. An interesting path in G is a directed path whose edges all have the same signature. Further, we define the interestingness score of such a path as a sum of its edge weights multiplied by a nonlinear function of their corresponding ranks, i.e., the depths of the edges along the path. Such a nonlinear function could model application use-cases where the growth in the dependent variable values is expected to be concentrated in specific intervals of a path, e.g., plant growth accelerating later in the season, or a terminally ill patient's health condition deteriorating rapidly toward the end.Second, we study three optimization problems on this graph G to quantify interesting subpopulations. In the problem MaxIP, the goal is to find the most interesting path in G, i.e., an interesting path with the maximum interestingness score. For the case where G is a directed acyclic graph (DAG), which could be a typical setting in many applications, we show that MaxIP can be solved in polynomial time---in O(mnd_in) time and O(mn) space, where m,n, and d_in are the numbers of edges, vertices, and the maximum indegree of a vertex in G, respectively.In the more general problem IP, the goal is to find a collection of interesting paths that are edge-disjoint, and the sum of interestingness scores of all paths is maximized. We also study a variant of IP termed k-IP, where the goal is to identify a collection of edge-disjoint interesting paths each with k edges, and the total interestingness score of all paths is maximized. While k-IP can be solved in polynomial time for k = 3 even when G is a DAG. We develop heuristics for IP and k-IP on DAGs, which use the algorithm for MaxIP on DAGs as a subroutine, and run in O(mnd_in) and O(mkd_in) time for IP and k-IP, respectively.
Promoting a veteran-friendly learning environment

The transitioning of veterans from the military world to 'the civilian world' and by extension the civilian workforce is the 'ultimate career transition.' However, to facilitate this challenge, most veterans often utilize higher education as a transitional tool to qualify themselves with credentials that are not only recognizable but valued by their potential civilian employer. Transitional challenges for the veteran student in higher education include a unified learning environment (veterans and civilians), a learning environment supported by unfamiliar learning theories, and differences in roles, for example instructor and student. Utilizing the transitional challenges veterans encounter while pursuing higher education as an underpinning, this chapter provides an overview of the veteran student, explores the transitional challenges veterans encounter while pursuing higher education and relevant support systems needed for success. Additionally, this chapter provides strategies that should be employed by adult educators in an effort to promote a veteran-friendly learning environment.
Social Networks in Later Life: Similarities and Differences between Sexual-Minority and Heterosexual Older Adults.

Community-based research suggests that lesbian, gay, and bisexual (LGB) older adults are more socially isolated than their heterosexual counterparts. However, little is known about how social netwo...
BOOKS: Review Forum

Caribbean Middlebrow: Leisure Culture and the Middle Class. By Belinda Edmondson. Ithaca: Cornell University Press, 2010. Pp. 223. ISBN 9780801448140. $45 (hbk). Belinda Edmondson's Caribbean Middl...
Geriatric Decision-Making in the Emergency Department: A Surgeon’s Perspective

Operative intervention on the geriatric population is technically similar to surgery on younger patients: the anatomy does not change, and the principles of surgery are the same; however, physiology does change, and so does the ability to withstand major surgery. This chapter will deal with geriatric surgical decision-making as considered from several different vantage points. We will consider physiologic and pharmacologic issues, as well as perioperative risk mitigation and stratification strategies; we will consider behavioral, cultural, and legal facets, as they pertain particularly to geriatric patients. In summation, the goal is to care for geriatric patients in a manner consistent with their desires and to be thoughtful about all of the complicating factors that may influence the decision to operate. This approach does not guarantee a good outcome, but it does guarantee a thoughtful and thorough approach to marrying the right level of intervention to each patient, consistent with her or his clinical condition and, perhaps more importantly, wishes.
A new plastomenid trionychid turtle, Plastomenus joycei , sp. nov., from the earliest Paleocene (Danian) Denver Formation of south-central Colorado, U.S.A.

North American soft-shelled turtles, including trionychines and plastomenids, are incredibly abundant in latest Cretaceous through earliest Paleocene sediments. Here we describe a new species of pl...
Choosing a Journal for Submission: Don’t Fall Prey

The column in this issue is supplied by Barbara Gastel, MD, MPH, who is professor of veterinary integrative biosciences and of humanities in medicine at Texas A&M University, where she coordinates the graduate program in communicating science. Dr. Gastel obtained her medical and public health degrees from Johns Hopkins University. She is first author of the current edition of How to Write and Publish a Scientific Paper (ABC-CLIO, 2016).
A simplified hydrodynamic mesoscale model suitable for use over high plateau regions

A simplified hydrodynamic primitive equation model in σ-coordinates is described. This model includes the main physical processes that influence development and motion of mesoscale vortices over plateau regions: elevated terrain effects, effects of large-scale and synoptic-scale systems on the mesoscale systems, sensible heating from the earth's surface, moisture cycle and condensation heating released by both large-scale stable precipitation and cumulus convective precipitation, evaporation and the feedback effect of precipitation on evaporation, friction in the planetary boundary layer, horizontal diffusion by subgrid scale eddies and vertical eddy flux of meteorological elements (momentum, temperature, moisture, etc.) due to turbulence, cumulus convection and other smaller-scale physical processes. The model incorporates observed data as much as possible and equations are simplified so that it may be run using either a high-speed computer or a desktop computer.
Aerodynamic Performance of a Drag Reduction Device on a Full-Scale Tractor/Trailer

The effectiveness of an aerodynamic boattail on a tractor/trailer road vehicle was measured in the NASA Ames Research Center 80- by 120-Foot Wind Tunnel. Results are examined for the tractor/trailer with and without the drag reduction device. Pressure measurements and flow visualization show that the aerodynamic boattail traps a vortex or eddy in the corner formed between the device and the rear corner of the trailer. This recirculating flow turns the flow inward as it separates from the edges of the base of the trailer. This modified flow behavior increases the pressure acting over the base area of the truck, thereby reducing the net aerodynamic drag of the vehicle. Drag measurements and pressure distributions in the region of the boattail device are presented for selected configurations. The optimum configuration reduces the overall drag of the tractor/trailer combination by about 10 percent at a zero yaw angle. Unsteady pressure measurements do not indicate strong vortex shedding, although the addition of the boattail plates increases high frequency content of the fluctuating pressure.
Building Preservice Teachers' Ability to Think Aloud in Literacy Methods Courses

An essential element in teaching children to effectively comprehend text is the use of teacher-led think alouds. The overarching objective of this study was to explore how to better prepare preservice teachers to conduct think alouds in their future classrooms. Data from 97 preservice teachers consisted of several sources: (a) questionnaires, (b) lesson plans, (c) lesson transcripts, and (d) written reflections. Preservice teachers made significant growth in the quantity and quality of reading comprehension strategies they incorporated. Discussion focuses on the challenges that participants encountered when thinking aloud. Finally, suggestions for supporting preservice teachers in effectively thinking aloud are provided.
Primary Afferent Terminals in Spinal Cord Express Presynaptic AMPA Receptors

Larger dorsal root ganglion neurons are stained by an antibody for the C terminus of glutamate receptor subunit 2 (GluR2) and GluR3 (GluR2/3) rather than by an antibody for GluR4. In dorsal roots, anti-GluR2/3 stains predominantly myelinated fibers; anti-GluR4 or anti-GluR2/4 stains predominantly unmyelinated fibers. In the dorsal horn, puncta immunopositive for synaptophysin and GluR2/3 are predominantly in laminas III and IV, whereas puncta immunopositive for synaptophysin and GluR4 or GluR2/4 are predominantly in laminas I and II. Puncta immunopositive for GluR2/3 costain with the B subunit of cholera toxin, whereas puncta immunopositive for GluR2/4 costain with isolectin B4 after injections of these tracers in the sciatic nerve. No puncta costain with calcitonin gene-related peptide and AMPA receptor subunits. Electron microscopy indicates that AMPA receptor-immunopositive terminals are more numerous than suggested by confocal microscopy. Of all synapses in which immunostaining is presynaptic, postsynaptic, or both, the percentage of presynaptic immunostain is approximately 70% with anti-GluR4 or anti-GluR2/4 (in laminas I-III), 25-30% with anti-GluR2/3 (in laminas III and IV), and 5% with anti-GluR2 (in laminas I-III). Because of fixation constraints, the types of immunostained terminals could be identified only on the basis of morphological characteristics. Many terminals immunostained for GluR2/3, GluR4, or GluR2/4 have morphological features of endings of primary afferents. Terminals with morphological characteristics of presumed GABAergic terminals are also immunostained with anti-GluR2/4 and anti-GluR4 in laminas I and II and with anti-GluR2/3 in laminas III and IV. The conspicuous and selective expression of presynaptic AMPA receptor subunits may contribute to the characteristic physiological profile of different classes of primary afferents and suggests an important mechanism for the modulation of transmitter release by terminals of both myelinated and unmyelinated primary afferents.
The Path of Most Resistance: IOs and Domestic Public Opinion

Securing Approval: Domestic Politics and Multilateral Authorization for War. By Terrence L. Chapman. Chicago: University of Chicago Press, 2011. 189 pp., $27.50 paperback (ISBN-13 9780226101224). The list of reasons that states, and the people who lead them, use in seeking approval from international organizations before taking action against other states is well known. For the realist, states need not concern themselves with international organizations at all; the realist expects forgiveness rather than asks permission for their actions, since organizations have no ability to punish them (Mearsheimer 1995). For the liberal, international organizations serve to legitimatize intervention, conferring upon it the widespread approval of a large number of states who together can agree upon its necessity. The constructivist might note that states seek approval because of who they are, and they believe it is the appropriate thing to do given a particular situation and set of actors (Wendt 1992; March and Olson 1998). To this list Terrence Chapman adds another reason: states seek approval for their interventions because “IO activity can provide information to audiences that are important to governments…IO authorization can provide valuable political cover for governments considering controversial and possibly threatening foreign policies” (p. 21). In building this argument, Chapman adds strength to the now well-established link between domestic and international politics, stressing the role of the citizen in decoding the messages sent by international organizations and the role of leaders in determining which international organization is the most appropriate venue for new foreign policy initiatives. Through the five empirical chapters in his book, Chapman investigates two basic questions. The first questions the circumstances under which leaders will seek out the approval of international organizations when they know that those organizations lack …
Inducible defenses, phenotypic variability and biotic environments

Defensive morphologies, chemicals and behaviors induced by cues from consumers or competitors have been described in numerous organisms. Much work has focused on the costs of defenses and the actual cues used. Here, we review recent progress in determining the effects of inducible defenses on consumers and the cues implicated in inducing defenses against consumers and competitors, thereby laying the groundwork for studying the implications of inducible defenses for the dynamics of foraging, population size and evolution.
Granulocyte Colony-stimulating Factor Induces Erk5 Activation, Which Is Differentially Regulated by Protein-tyrosine Kinases and Protein Kinase C REGULATION OF CELL PROLIFERATION AND SURVIVAL

Granulocyte colony-stimulating factor (G-CSF) plays a major role in the regulation of granulopoiesis. Treatment of cells with G-CSF has been shown to activate multiple signal transduction pathways. We show here that Erk5, a novel member of the MAPK family, and its specific upstream activator MEK5 were activated in response to incubation of cells with G-CSF. Different from other members of the MAPK family including Erk1/2, JNK, and p38, maximal activation of Erk5 by G-CSF required the C-terminal region of the G-CSF receptor. Genistein, a specific inhibitor of protein-tyrosine kinases, blocked G-CSF-induced Erk5 activation. In contrast, inhibition of protein kinase C activity increased G-CSF-mediated activation of Erk5 and MEK5, whereas stimulation of protein kinase C activity inhibited activation of the two kinases by G-CSF. The proliferation of BAF3 cells in response to G-CSF was inhibited by expression of a dominant-negative MEK5 but potentiated by expression of a constitutively active MEK5. Expression of the constitutively active MEK5 also increased the survival of BAF3 cells cultured in the absence of or in low concentrations of G-CSF. Together, these data implicate Erk5 as an important signaling component in the biological actions of G-CSF.
Orbital architectures with dynamic reconfiguration

Several broad classes of nonplanar arrays/architectures are analysed. Included in this are architectures which have a natural interpretation in terms of data flow on the surface of a torus, sphere, cylinder and other geometric forms. A definitive quantification is given of the several architectural classes and architectural reconfiguration is demonstrated to facilitate iterative computations.
Surviving Drosophila eye development: integrating cell death with differentiation during formation of a neural structure.

Normal differentiation requires an appropriately orchestrated sequence of developmental events. Regulation of cell survival and cell death is integrated with these events to achieve proper cell number, cell type, and tissue structure. Here we review regulation of cell survival in the context of a precisely patterned neural structure: the Drosophila compound eye. Numerous mutations lead to altered differentiation and are frequently accompanied by altered patterns of cell death. We discuss various critical times of normal eye development, highlighting how inappropriate regulation of cell death contributes to different mutant phenotypes associated with genes that specify the entire eye primordia, others that pattern the retina, and those that eliminate extraneous cells to refine the precise pigment cell lattice. Finally, we address how the Drosophila eye may allow identification of additional mechanisms that contribute to the normal integration of cell survival with appropriate events of cellular differentiation. BioEssays 21:991–1003, 1999. © 1999 John Wiley & Sons, Inc.
Development and characterization of 12 microsatellite loci for the Dwarf Salamander, Eurycea quadridigitata

We isolated and characterized 12 microsatellite loci for the Dwarf Salamander, Eurycea quadridigitata. Loci were screened in 30 individuals of E. quadridigitata. The number of alleles per locus ranged from 2 to 9, observed heterozygosity ranged from 0.2 to 0.9, and the probability of identity values ranged from 0.034 to 0.689. These new loci can be used to study population genetic structure and potentially help determine cryptic species divergence.
Studies involving labile vitamin B1 metal complexes. Part 2. Infrared, nuclear magnetic resonance studies, structure and binding site determination

Abstract Potassium tetrachloroplatinate(II) reacts with labile Vitamin B 1 , Hg(Th)Cl 4 ·H 2 O (1:1 mol ratio) in warm aqueous medium to form the very stable trinuclear complex, HgPt 2 (Th)Cl 6 . Two structures are proposed - one in which mercury is presumably two-coordinated and platinum is penta-coordinated, and another in which mercury is tetracoordinated and platinum is penta-coordinated through chlorine bridges. On the contrary, the same metal salt reacts with Zn(Th)Cl 4 ·H 2 O and Cd(Th)Cl 3 ·H 2 O to form dinuclear complexes, ZnPt(Th)Cl 3 and CdPt(Th)Cl 3 in which zinc or cadmium is two-coordinated and platinum is tetracoordinated. These novel tri- and dinuclear complexes were characterized by 1 H, 13 C NMR, IR and elemental analysis.
Improving the Labeling of S-Acetyl NHS−MAG3-Conjugated Morpholino Oligomers

S-Acetyl MAG 3 (S-acetylmercaptoacetyltriglycine) has been used as a chelator for the 9 9 m Tc labeling of a variety of biomolecules. The objective of this study was to improve upon the labeling of morpholino (MORF), a DNA analogue, as a model biomolecule. A 15mer MORF with a primary amine was conjugated with NHS-MAG 3 in the usual manner, and the MORF-MAG 3 was purified over a P4 column as before. The conjugate was radiolabeled using stannous ion as usual, and the impurities were identified using size exclusion high-performance liquid chromatography (SE HPLC). Various methods were then investigated to remove the impurities. With tartrate as the transchelator, two impurities were identified as labeled MAG 3 and labeled tartrate. The labeled MAG 3 could not be removed by simply repurifying the conjugate using the usual pH 5.2 NH 4 OAc buffer before labeling. However, this impurity could be completely removed if the conjugate was adjusted to pH 7.6 and heated before repurification. The labeled tartrate impurity was removed by heating during labeling. On the basis of these observations, the following procedure for purification of the conjugation mixture and subsequent labeling was adopted. After MORF was conjugated with NHS-MAG 3 and purified over P4 with pH 5.2 NH 4 OAc eluant, the oligomer fractions were combined, adjusted to pH 7.6, and heated in a boiling water bath for 20 min. The conjugated oligomer was then repurified over P4 for storage at refrigerator temperatures. Labeling is achieved simply by adding fresh stannous ion to a solution of the MORF-MAG 3 in pH 7.6 containing tartrate followed by 9 9 m Tc-pertechnetate. After the mixture is heated for 20 min in boiling water, the labeling efficiency is always over 90% as determined by size exclusion HPLC and paper chromatography and the specific activities can exceed 7 mCi/μg. By making several relatively simple changes to the routine procedure used to conjugate and radiolabel biomolecules with 9 9 m Tc via MAG 3 , a modified procedure was developed that results in labeling efficiency high enough to avoid postlabeling purification.
Models for the Permeability of Filled Polymer Systems

Abstract A theory has been developed which predicts the minimum permeability that can be expected for a polymer filled with platelike particles. Models are also developed for the permeability of liquids through filled polymers when the liquid adsorbs or collects at the filler-polymer interface. Some of the cases discussed include different types of dispersions, orientation of filler particles, and the effects of filler aggregation. Permeability, especially of liquids, is extremely complex, and many different types of behavior can be expected.
Dislocation interactions in thin FCC metal films

Abstract High strength, high hardening rates, and strong Bauschinger-like effects in thin films have been attributed to constraints on dislocation motion and dislocation interactions. To understand these phenomena, dislocation interactions in (1 1 1) and (0 0 1) oriented single crystal FCC films were studied using dislocation dynamics simulations. Interactions on intersecting glide planes resulted in junction formation, annihilation, or attractive non-junction-forming configurations, while dislocations on parallel glide planes formed dipoles. The configurations adopted by interacting dislocations, and thus the strengths of the interactions, were found to be sensitive to the applied strain, film thickness, crystallographic orientation, and boundary conditions. Different interactions thus dominate film behavior in different ranges of film thickness and applied strain. Interactions are stronger on unloading than on loading. Interactions involving three or more dislocations are found to be different from pairwise interactions. The results suggest that simple analytical calculations are unlikely to describe film phenomena but that full 3-D simulations can be used to understand many features of thin film mechanical behavior.
A Paperless Gamble

For the first time in nearly half a century, a printed copy of Computer won't be shipped as an included member benefit. I offer some thoughts on the matter.
Metabolism of cisanilide (Cis-2,5-dimethyl-1-pyrrolidinecarboxanilide) by rat liver microsomes☆

Metabolism of [phenyl-14C] and [(2,5) pyrrolidine-14C] cisanilide was investigated in vitro with microsomal preparations from rat liver. Microsomal activity was associated with a mixed-function oxidase system that required O2 and NADPH and was inhibited by CO. Two major ether-soluble metabolites were isolated. They were identified as primary oxidation products: 2-hydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide (A) and 4′-hydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide (B). Minor ether-soluble metabolites were also isolated. Precursor product studies and qualitative thin layer chromatography analysis of [pyrrolidine-14C] and methylated [phenyl-14C] hydrolysis products suggested that these metabolites were secondary oxidation products formed from metabolites A or B. One of these metabolites appeared to be the dihydroxy product 2,4′-dihydroxy-2,5-dimethyl-1-pyrrolidinecarboxanilide. Crude microsomal preparations (postmitochondrial supernatant fractions) also formed small quantities (<10%) of polar metabolites. Enzyme hydrolysis with β-glucuronidase (Escherichia coli) indicated that approximately 50% of these metabolites were glucuronides. Similarities and differences in cisanilide oxidation in vivo in plants and in vitro with rat liver microsomal preparations were discussed.
Quantitative imaging of dynamic structure and function of the heart, lungs and circulation by computerized reconstruction and subtraction techniques

Conventional radiographic imaging techniques are not adequate for determination of the true, dynamic changes in shape and dimensions of the intact working heart, lungs and circulation which are required for accurate quantitative determination of the structure and function of these organ systems. This paper describes a computerized method for obtaining images of the dynamic spatial distribution of x-ray attenuation throughout multiple parallel cross-sectional planes bisecting the intact thorax, with 1-mm spatial resolution and 60-per-second temporal resolution, and for generating time delay video and cine displays of the spatial and temporal sequences of these cross-sectional images. Operator-interactive computer programs facilitate the dynamic display of reconstructed cross sections of the heart and lungs, with or without dynamic background subtraction, and permit calculation and display of any desired single or spatially related set of coronal, sagittal or obliquely oriented sections. Such displays permit viewing of the temporal and spatial distribution of contraction, expansion, and perfusion of these organs over their full anatomic extent in various orientations and in variable time-base modes ranging from stop-action to real-time. The results achieved with this computerized system for three-dimensional reconstruction and display of moving organs, particularly the heart, lungs, and circulation, demonstrate the potential for providing greatly improved techniques for investigation of the relationships of the dynamic three-dimensional anatomy and blood-tissue exchange properties of moving organ systems to their regional and integrated function, and ultimately for providing powerful new clinical diagnostic methods for elucidation of abnormalities of the heart, lungs and circulation in man.
Building Constructivist, Contextual, and Dynamic Foundations to Further Students' Understanding of Families and Poverty

Abstract A comprehensive approach to the study of family poverty addresses the overlap between narratives, social context, and history. Perspectives on lived experiences of poverty within social institutions emerge from constructivist, ecological, and life course theoretical frameworks are shared. In this article, consideration is given to teaching about the changing nature of family poverty by examining lives in social systems over time. Three strategies are helpful for instruction in family poverty. These strategies involve asking students to reflect on meaning making for families in poverty; to explore poor families' daily interactions with social institutions; and to examine dynamic historical experiences of these families. With this informed and imaginative work, students can become engaged and develop insight into the lived experiences of low-income families.
NASA hypersonic flight demonstrators—overview, status, and future plans

Abstract NASA's Next Generation Launch Technology (NGLT) program is developing and maturing advanced propulsion and vehicle systems technologies and flight vehicle concepts to enable future development of safer and more economical launch systems. Within NGLT, NASA is developing advanced air breathing propulsion systems and demonstrating these systems in hypersonic flight vehicles. The flight demonstrations are necessary to fully validate these technologies for application to future space launch vehicles and other flight systems. NASA's Hyper-X Program (X-43A) began the effort to flight demonstrate hypersonic air breathing propulsion systems to provide technologies that will enable development of safer and more economic space access vehicles in the future. Following X-43A, NASA, in collaboration with the United States (US) Department of Defense (DoD), is developing additional, progressively more complex hypersonic X-vehicles that will demonstrate new air breathing propulsion systems, propulsion-airframe integration, and other vehicle systems technologies required for high speed flight up to Mach 15. These technologies will contribute to safer, more reliable and more economic future launch systems and hypersonic aircraft/missiles. This paper describes NASA's current hypersonic flight demonstration projects, status of the efforts, and plans for future vehicles.
Design of MEMS and microsystems

Facile, integrated and comprehensive software is needed for the design of processes, models and simulation, which are required for effective production of MEMS and microsystems. The characteristics of computer-aided design software now available from seven companies are reviewed. Three of the firms have roots in microelectronics, and three were formed specifically for MEMS design. Electronic, mechanical, thermal and fluidic mechanisms are commonly included. One company is especially strong in microfluidics. Two of the design suites permit computational coupling between a MEMS device and its package. High spatial- and temporal- resolution optical diagnostics are now producing detailed data that will challenge design and simulation software for MEMS and microsystems. Near and far term prospects for the CAD of MEMS and microsystems are projected.
Perceived serosorting of injection paraphernalia sharing networks among injection drug users in Baltimore, MD

We examined perceived serosorting of injection paraphernalia sharing networks among a sample of 572 injection drug users (IDUs). There was evidence for serosorting of high-risk injection behaviors among HIV-negative IDUs, as 94% of HIV-negative IDUs shared injection paraphernalia exclusively with perceived HIV-negative networks. However, 82% of HIV-positive IDUs shared injection paraphernalia with perceived HIV-negative networks. The findings indicate a potential risk of rapid HIV transmission. Future prevention efforts targeting IDUs should address the limitation of serosorting, and focus on preventing injection paraphernalia sharing regardless of potential sharing networks’ perceived HIV status.
Low-flow cardiopulmonary bypass produces greater pulmonary dysfunction than circulatory arrest

Background. Deep hypothermic circulatory arrest (DHCA) is used during the repair of congenital heart disease in neonates. However, because of concern about neurologic injury after DHCA, there is increasing use of continuous deep hypothermic low-flow cardiopulmonary bypass (DHCPB). This study examines the effects of DHCPB versus DHCA on pulmonary dynamics in 1-week-old piglets (weight range, 2.5 to 3.5 kg). Methods. Animals were placed on CPB (37°C) at 100 mL · kg −1 · min −1 , cooled to 18°C, and then assigned to one of two groups: DHCPB (n = 7), 25 to 50 mL · kg −1 · min −1 DHCPB for 90 minutes; or DHCA (n = 8), DHCA for 90 minutes. Animals were rewarmed to 37°C, weaned from CPB, and observed for 30 minutes. Static pulmonary compliance and pulmonary vascular resistance index were assessed before CPB, 5 minutes after CPB, and 30 minutes after CPB. Results. There was greater impairment of static pulmonary compliance after DHCPB compared with 90 minutes of DHCA. There was a trend toward higher pulmonary vascular resistance index in the DHCPB group; however, significance was not reached. Conclusions. Deep hypothermic low flow cardiopulmonary bypass produces greater pulmonary dysfunction than DHCA, manifested by decreased static pulmonary compliance. If DHCPB is used in place of DHCA in congenital heart operations, close attention to ventilatory and fluid management is mandatory in the postoperative period to prevent further worsening of pulmonary dysfunction.
Technology and Lifestyles: Challenges for Leisure Education in the New Millenium

Abstract This paper examines the opportunities, disappointments and impact of technology upon lifestyles and leisure, and proposes leisure education strategies to achieve active and healthy lifestyles in the new millennium. Technology has increased productivity and efficiency at the worksite and in the home, created new and expanding opportunities for leisure, and promised shorter work weeks with more opportunities for leisure. Unfortunately, the reality has fallen short of the promise. Technology has removed labor from our daily activities and facilitated inactive forms of leisure to remove physical activity from our lifestyles. We enter the new millennium as a busy, stressed and sedentary society; working more hours, performing little or no physical activity, with fewer opportunities for leisure, and challenged by an epidemic of chronic disease outcomes associated with physical inactivity. This paper advocates active leisure as an antidote to our increasingly sedentary lifestyles, the need for leisure e...
Creating a Paperless Workflow: A Case Study

In any traditional organization where requests must go through a chain of approval, the work and volume of paper forms seems to grow exponentially by each level of approval. This was the case at the University of Tennessee, Memphis. To cut down on the time, expense, and clutter associated with paper approval forms, an electronic system was designed and implemented. This article tells the story of how this was accomplished.
Modeling Aerosol Formation from α-Pinene + NOx in the Presence of Natural Sunlight Using Gas-Phase Kinetics and Gas-Particle Partitioning Theory

A kinetic mechanism was used to link and model the gas-phase reactions and aerosol accumulation resulting from α-pinene reactions in the presence of sunlight, ozone (O3), and oxides of nitrogen (NOx). Reaction products and aerosol formation from the kinetic model were compared to outdoor smog chamber experiments conducted under natural sunlight in the presence of NOx and in the dark in the presence of O3. The gas−particle partitioning of semivolatile organics generated in the gas phase was treated as an equilibrium process between particle absorption and desorption. Models vs experimental aerosol yields illustrate that reasonable predictions of secondary aerosol formation are possible from both dark ozone and light NOx/α-pinene systems over a variety of different outdoor conditions. On average, measured gas- and particle-phase products accounted for ∼54−72% of the reacted α-pinene carbon. Model predictions suggest that organic nitrates account for another ∼25% of the reacted carbon, and most of this is in...
Toward an understanding of English syllabification

Abstract Using written and oral syllabification tasks and analyses of spelling errors, we studied how college students syllabify words with medial consonant clusters. Several principles of syllabification were evident. People almost always separated the phonemes of a cluster like /tl/, which is illegal at the beginnings and ends of words. A “short” vowel tended to attract consonants to its syllable, as did a stressed vowel. Finally, different syllabifications were produced for clusters like /dr/, which show the typical rise in sonority from the first consonant to the second, and /st/ clusters, which do not. Implications of the results for linguistic theories of syllabification and for studies of the syllable's role in speech perception and reading are discussed.
NK Cell-Derived Interferon-γ Orchestrates Cellular Dynamics and the Differentiation of Monocytes into Dendritic Cells at the Site of Infection

Summary Dendritic cells (DCs), monocytes, and/or macrophages initiate host-protective immune responses to intracellular pathogens in part through interleukin-12 (IL-12) production, although the relative contribution of tissue resident versus recruited cells has been unclear. Here, we showed that after intraperitoneal infection with Toxoplasma gondii cysts, resident mononuclear phagocytes are replaced by circulating monocytes that differentiate in situ into inflammatory DCs (moDCs) and F4/80 + macrophages. Importantly, NK cell-derived interferon-γ (IFN-γ) was required for both the loss of resident mononuclear phagocytes and the local differentiation of monocytes into macrophages and moDCs. This newly generated moDC population and not the resident DCs (or macrophages) served as the major source of IL-12 at the site of infection. Thus, NK cell-derived IFN-γ is important in both regulating inflammatory cell dynamics and in driving the local differentiation of monocytes into the cells required for initiating the immune response to an important intracellular pathogen.
Video game experience predicts virtual, but not real navigation performance

In recent years, studies have shown that video game experience is related to improvements across a variety of cognitive and visuospatial tasks. This study investigated the relationship between prior video game experience and spatial performance in virtual and real environments. Across two experiments, gaming experience was related to performance in desktop virtual environments; those with more video game experience were more accurate in pointing to nonvisible targets. In contrast, gaming experience was unrelated to three different real environment tasks, suggesting that video games may primarily influence perceptual and cognitive abilities in the visual domain over abilities that also involve kinesthetic or vestibular input. Contrary to expectations, gaming experience was also related to performance in immersive virtual environments, which may be related to the use of a joystick interface during immersive travel. Video game experience was also positively related to performance in a dynamic spatial task and to verbal SAT and math SAT scores. Sex differences in desktop virtual navigation and dynamic spatial ability were eliminated when game experience was included as a covariate.
The use of complexity-based models in international relations: a technical overview and discussion of prospects and challenges

Complexity has become an ubernotion for a contemporary perception of many social phenomena. This is mirrored by the existence and advent of an array of methods and theories that describe complex social phenomena, including in International Relations (IR). However, many scholars fall short of explaining what it is they call ‘complexity’, how the notion of complexity can help to better understand IR and which kinds of methodologies support such analyses. This article provides an overview and critical discussion of the latter. The notion of complexity and its underlying concepts are briefly clarified and methodological aspects and challenges are discussed. It is explained which social phenomena within the realm of IR are most promisingly studied under a complexity paradigm. Three modelling examples are given for illustration that allow for the identification of methodological and epistemological limits and the anticipation of potential prospects of a complexity-based modelling approach to IR.
Mass spectrometry-based fragmentation as an identification tool in lignomics.

The ensemble of all phenolics for which the biosynthesis is coregulated with lignin biosynthesis, i.e., metabolites from the general phenylpropanoid, monolignol, and (neo)lignan biosynthetic pathways and their derivatives, as well as the lignin oligomers, is coined the lignome. In lignifying tissues, the lignome comprises a significant portion of the metabolome. However, as is true for metabolomics in general, the structural elucidation of unknowns represents the biggest challenge in characterizing the lignome. To minimize the necessity to purify unknowns for NMR analysis, it would be desirable to be able to extract structural information from liquid chromatography−mass spectrometry data directly. However, mass spectral libraries for metabolomics are scarce, and no libraries exist for the lignome. Therefore, elucidating the gas-phase fragmentation behavior of the major bonding types encountered in lignome-associated molecules would considerably advance the systematic characterization of the lignome. By co...
Increased estrogen receptor alpha in experimental aortic aneurysms in females compared with males

Abstract Background Estrogen receptor alpha (ERα) has been identified in the vessel wall, offering vasoprotective effects when upregulated. Estrogens are known to mediate the inflammatory milieu, and inflammation has long been associated with abdominal aortic aneurysm (AAA) formation. Therefore, it is theorized that increased estrogen receptor in females contributes to their relative resistance to AAAs. The objective of this study was to determine gender differences in ERα levels during experimental AAA formation. Methods Infrarenal aortas of male and female C57 mice (n = 18 and n = 16, respectively) were infused with 0.4% elastase. Diameters were measured at days 0 and 14. Aortic messenger RNA expression of ERα was determined on day 3 by reverse transcription–polymerase chain reaction, whereas ERα protein levels were measured via Western blot. Immunohistochemistry using rabbit antibody for ERα was performed on day 14 samples and quantified. Zymography was done for matrix metalloproteinases (MMP)2 and 9 activity levels. Samples of human AAAs were collected and Western blot performed. Data were compared for significance using a student t-test. Results Infrarenal aortic diameter increased in elastase-perfused males (ME) by 80% at 14 days after perfusion, whereas females (FE) increased by only 35% (P = 0.0012). FE had ×10 greater ERα messenger RNA expression compared with ME at day 3 (P = 0.003). Similarly, ERα protein levels were 100% higher in FE compared with those in ME on day 14 (P = 0.035). ERα protein levels were 80% higher in female human patients with AAA than those in their male counterparts (P = 0.029). ERα visualized via immunohistochemistry was 1.5 fold higher in FE than ME (P = 0.029). MMP2 and 9 activity levels were decreased in female compared with male aortas. Conclusions This study demonstrates an increase in aortic wall ERα in females compared with males that correlates inversely with MMP activity and AAA formation. These findings, coupled with observations that exogenous estrogen inhibits AAA formation in males, further suggest that estrogen supplementation may be important to prevent AAA formation and growth.
Counting EBV and T cells to predict PTLD

Epstein-Barr virus (EBV)–induced lymphoproliferative disease (PTLD) is a common and often fatal complication of transplantation and immunocompromise. Treatments for PTLD are more effective if initiated early, and high levels of EBV DNA in the peripheral blood of these individuals are a sensitive