cssi/SciSciGPT-SciSciNet huggingface dataset:
A computational study of the interactions of three adjacent burning shrubs subjected to wind

A three-dimensional physics-based model was used to investigate the effect of shrub size, shrub separation distance and wind on the burnout times of shrubs. The shrub considered for this study was chamise. Two shrub sizes with different physical dimensions and initial masses with two wind speeds were considered. The study was performed for an array of three shrubs with separation distances ranging from zero to one shrub diameter. The shrubs were situated at the vertices of an equilateral triangle with two shrubs placed upwind (upstream shrubs) of the third shrub (downstream shrub). For a smaller shrub and a higher wind speed, the direction of fire front propagation within the shrub was found to be opposite to the direction of the wind, which resulted in a longer burning time for the shrub. For larger shrubs, a decrease in burning time was observed with an increase in wind speed. The burnout time for upstream shrubs increased with an increase in shrub separation distance for all shrub sizes and wind speeds considered. The burnout time for the downstream shrub was found to decrease with an increase in the separation distance, reach a minimum, and then increase with an increase in separation distance. The trends observed in burnout times for downstream shrub were attributed to the balance between heat feedback into the downstream shrub from the flames in upstream shrubs and availability of sufficient oxygen for combustion to take place.
Carbon dioxide hydrogenation: Efficient catalysis by an NHC-amidate Pd(II) complex

Abstract The utilization of carbon dioxide as a carbon source has long been a challenge in modern organic chemistry due to its low reactivity, yet high abundance. Herein we demonstrate the highly efficient hydrogenation of carbon dioxide into formic acid in the presence of an NHC-amidate Pd(II) complex. Excellent turnover number was observed when the catalyst was used under heterolytic conditions. This catalytic system provides a new and efficient carbon dioxide hydrogenation method.
Supply chain resilience for single and multiple sourcing in the presence of disruption risks

This paper investigates the use of sourcing strategies to achieve supply chain resilience under disruptions. The coping strategies considered are single and multiple sourcing, backup supplier contracts, spot purchasing, and collaboration and visibility. Collaboration and visibility, which affect suppliers’ recovery capabilities and a buyer’s warning capability, have not been similarly modelled in the past. A scenario-based mathematical model is developed such that it considers objectives under uncertainties including disruption risks and operational risks. A broad numerical study examines its output for various risk attitudes in a decision-maker, ranging from risk neutral to risk averse. The sensitivity of procurement strategies to other key parameters such as recovery and warning capabilities is examined. One of the major findings is that buyer’s warning capability plays a vital role in enhancing supply chain resilience. We seek to build on these efforts to further support disruption planning and mitigat...
Corticosterone mobilizes monocytes into circulation and induces endothelial adhesion molecule expression to cause monocyte recruitment to the brain during stress

Repeated social defeat stress causes release of bone marrow-derived monocytes into circulation and increases endothelial cell adhesion molecule expression to promote monocyte recruitment to the brain. Sympathetic activation during stress has been previously associated with increased circulating monocytes in the blood. However, stress also activates the hypothalamic-pituitary-adrenal axis to secrete corticosterone (cort). To understand the role of cort in immune dysregulation during stress, adrenalectomized (ADX) mice and non-ADX mice were exposed to six days of repeated social defeat stress. ADX mice produced the same levels of bone marrow monocytes as non-ADX mice but released fewer cells into circulation during stress. We show here for the first time that the chemokine CXCL12, involved in retention of bone marrow cells, was reduced during stress - an effect prevented by ADX. Stress-induced increases in monocytes and intercellular adhesion molecule 1 (ICAM1) expression in the brain were also prevented by ADX. Notably, ADX independently altered key regulatory genes (CX3CR1, nr4a1) in microglia. ADX prevented morphological remodeling of microglia during stress but did not prevent expression of proinflammatory cytokines. Overall, we show here that corticosterone promotes mobilization of monocytes in the periphery, and their recruitment to the brain via endothelial cell adhesion molecule expression. Furthermore, physiological corticosterone is necessary for microglia homeostasis, and corticosterone depletion and over-production can both lead to microglial dysregulation in the brain.
Identifying Bottlenecks in Serial Production Lines with Geometric Machines: Indicators and Rules

Abstract In this paper, we develop a practical decision making tool to analyze and detect system bottlenecks for serial production lines with multiple Geometric machines and finite buffers. Systematic approaches are investigated to quantify the overall system performance-the production rate and its interactions with characteristics of individual machines. Two types of bottlenecks are defined and their corresponding indicators are derived to provide guidelines on improving system performance. These methods provide quantitative tools for modeling, analyzing, and improving manufacturing systems where machine’s downtime is significantly longer than the cycle time.
Numerical Approximation to Invariant Measures

Continuing with the development in Chapter 5, this chapter is devoted to additional properties of numerical approximation algorithms for switching diffusions, where continuous dynamics are intertwined with discrete events. In this chapter, we establish that if the invariant measure exists, under suitable conditions, the sequence of iterates obtained using Euler-Maruyama approximation converges to the invariant measure.
Evidence-Based Interventions for Transitions in Care for Individuals Living With Dementia.

Background and objectives Despite numerous, often predictable, transitions in care, little is known about the core elements of successful transitions in care specifically for persons with dementia. The paper examines available evidence-based interventions to improve the care transitions for persons with dementia and their caregivers. Research design and methods A state-of-the-art review was conducted for research published on interventions targeting transitions in care for persons living with dementia and their caregivers through January 2017. Results Our review revealed seven evidence-based interventions to postpone/prevent or reduce care transitions specific to persons living with dementia. Effective approaches appear to be those that involve the individual and caregiver in establishing goals of care, educate the individual and caregiver about likely transitions in care; provide timely communication of information about the individual, create strong inter professional teams with competencies in dementia care, and implement evidence-based models of practice. Discussion and implications Five essential features for consistent and supported care transitions for persons with dementia and their caregivers are recommended. Findings reinforce the need for additional research and adaptation of evidence-based transitions in care interventions.
MST for Space-Filling Cells

In this chapter, we discuss the generalization of MST to the case of non-MT, space-filling potential cells. As we did in the case of MT potentials, we develop the formalism within the angular-momentum representation. We show that MST is valid in the general case of nonoverlapping, space-filling scattering regions, retaining the basic features that characterize its application to MT potentials. In particular, it retains the separation of potential and structure from which MST derives much of its conceptual transparency and computational usefulness. We begin with a summary of the developments that led ultimately to the generalization of MST to space-filling potentials.
Role of Cyclic Nucleotides in the Nervous System

The complexity of the central nervous system makes investigation and elucidation of the factors involved in the establishment, regulation, and integration of neuronal function a formidable task. However, on the molecular level a variety of evidence indicates that the nucleotides cyclic AMP and cyclic GMP are involved in regulatory roles associated with neuronal function. Cyclic AMP regulates prime functions in many other tissues: gluconogenesis in liver, lipolysis in fat, secretion in endocrine glands. Definitive roles for cyclic GMP have as yet not been established (cf. Goldberg et al.,1973). These cyclic nucleotides are formed from intracellular ATP and GTP, respectively, by the action of cyclase enzymes. The cyclic nucleotides are degraded by phosphodiesterases to their respective 5′-phosphates. The diverse biological effects of cyclic nucleotides appear to be manifested through activation of protein kinases which specifically phosphorylate enzymes and other functional proteins and thus alter their properties. The specificity and nature of the effects of cyclic nucleotides presumably depend, therefore, not only on the intracellular site of generation of the cyclic nucleotide but also on the substrate specificity of the activated kinases and the accessibility of endogenous protein substrates. Termination of the physiological effects initiated by the cyclic nucleotides presumably occurs via the action of phosphoprotein phosphatases which hydrolyze the phosphorylated proteins. In certain instances, levels of cyclic AMP and cyclic GMP appear to be interrelated; increases in one nucleotide are accompanied by decreases in the other, suggesting a functional interrelationship.
Degloving injury from a helicopter rotor strike

The incidence of helicopter accidents has decreased, but lethality remains considerable. Rotor strikes are deadlier than crash-related injuries. We describe a degloving injury caused by a helicopter tail rotor strike managed with rapid resuscitation and early split-thickness skin grafting.
THE EFFECTIVENESS OF GROOVED COVER SURFACES IN REDUCING CONVECTIVE HEAT LOSS FROM SOLAR COLLECTORS

ABSTRACT Grooved cover surfaces were tested to determine whether they were effective in reducing convective heat loss from solar collectors. The convective heat transfer coefficients of two grooved samples and one smooth sample were measured in a wind tunnel at windspeeds of 0–10 mph and angles of 0, 4–5, and 90 degress. The transmittance of each sample was measured using a pyranometer on a sunny day. Convective heat transfer coefficients were generally larger for the grooved samples than for the smooth control indicating that the fin effect of increased surface area predominates over recirculation zones caused by the grooving. Together with decreased transmittance found for grooved samples, this leads to the conclusion that grooved cover surfaces would be deleterious to collector performance.
THE ROLE OF LIPID A AND LIPID A-ASSOCIATED PROTEIN IN CELL DEGRANULATION MECHANISMS

ABSTRACT The mechanisms by which bacterial endotoxins bring about the release of vasoactive amines from inflammatory mediator cells have been examined. Particular attention has focused upon stimulation of rat peritoneal mast cells and rabbit platelets. In the former experimental system, the protein component of endotoxin (LAP-lipid A associated protein) has been demonstrated to initiate secretion of granule-localized histamine and serotonin from mast cells. The release of similar constituents from rabbit platelets may be accomplished either by endotoxin-mediated, serum complement-dependent platelet lysis or by lipid A-induced calcium dependent platelet secretion. The former platelet response is dependent upon the alternative complement pathway and is enhanced significantly by LAP. The latter secretory response is elicited only by endotoxins from rough mutants and does not require the presence of serum. The relative contribution of these mechanisms to the hypotension characteristic of gram negative sepsis is assessed.
Astroglia: Receptors, Second Messengers, and Function

Research from a large number of laboratories has demonstrated that astroglia (GFAP positive cells in primary culture) exhibit a wide variety of neuroligand receptors (Cornell-Bell and Finkbeiner, 1991; Wilkin et al., 1990; Murphy and Pearce, 1987). Furthermore, it is evident that collectively these different astroglial receptor systems regulate most, if not all, of the known second messenger systems and that activation of these systems influences many different intracellular processes (Cummins et al., 1983; Hauser et al., 1990; Furukawa et al., 1987; Martin et al., 1988). While a large body of information has accumulated over the past two decades concerning the properties of astroglia, far less progress has been made toward understanding how these properties participate in brain physiology (ie. what is the function of astrocytes in brain?). The lack of information in this arena stems primarily from the absence of model systems whereby astrocytes can be studied in situ. However, information obtained using in vitro systems continues to provide important insight into the potential role of astrocytes in brain.
9.33 Field and Laboratory Experiments in Fluvial Geomorphology

This chapter reviews a broad range of true experiments with precisely controlled conditions, intentional and controlled interference, and a high level of ability to falsify hypotheses, which are typically conducted in physical models or flumes. The chapter also reviews field experiments, which are more likely to be hybrid experiments that involve a formal sampling design and a systems framework, but with reduced control over variables, or quasi-experiments involving informed selection of morphologic units of interest and substitution of experienced judgment for formal experimental design. Field experiments can be differentiated as those at (1) the channel-unit scale of ∼0–10 channel widths, such as controlled manipulation of boundary roughness, sediment supply, or instream wood; (2) the channel-reach scale of ∼10–100 channel widths, such as intentional levee breaches or the introduction of tracer clasts; and (3) the basin scale of >100 channel widths, such as manipulation of flow regime or channel planform. The extensive literature on flume experiments is here divided into experiments focused on (1) interactions between the flow and channel boundaries; (2) sediment dynamics (entrainment, transport, and deposition); (3) bedforms; (4) instream wood; (5) channel processes and biota; (6) channel patterns; (7) erosion of cohesive channels; (8) depositional landforms; and (9) drainage networks.
Misaligned Accretion Disc Formation via Kozai-Lidov Oscillations

We investigate the formation and evolution of misaligned accretion discs around the secondary component of a binary through mass transfer driven by Kozai-Lidov oscillations of the circumprimary disc's eccentricity and inclination. We perform SPH simulations to study the amount of mass transferred to the secondary star as a function of both the disc and binary parameters. For the range of parameters we explore, we find that increasing the disc aspect ratio, viscosity parameter and initial inclination as well as decreasing the binary mass ratio leads to larger amount of mass transfer, up to a maximum of about ten per cent of the initial mass of the primary disc. The circumsecondary disc forms with a high eccentricity and a high inclination and is also able to undergo KL oscillations. The circumsecondary disc oscillations have a shorter period than those in the disc around the primary. We find that some of the material that escapes the Roche-lobe of the two components forms a narrow misaligned circumbinary accretion disc. This study has implications for disc evolution in young binary star systems.
Culturally Sensitive OCD Research: Lessons from the U.S.-Mexico Border.

This paper explores culturally-related concerns that arose during a multi-year study of obsessive-compulsive disorder (OCD) along the U.S.-Mexico border and describes adaptations made to better con...
Aviation carbon emissions, route choice and tourist destinations: Are non-stop routes a remedy?

Abstract Air travel emissions comprise 20% of tourism's global carbon footprint. The purpose of this study was to determine whether non-stop routes to tourist destinations can mitigate air travel carbon emissions relative to routes that connect through airline hubs. Based on International Civil Aviation Organization data, we analyzed carbon emissions for both direct and connecting routes between the ten most populated metropolitan areas located in the Northeastern United States and 13 different tourist destinations located in the Sunbelt and Western regions of the US. Direct routes generally outperformed connecting routes regarding carbon emissions, although there were several exceptions. On average, non-stop routes reduced carbon emissions by roughly 100 kg/person relative to the next best connecting option.
Relay protection method based on decentralised control logic based on two side active excitation detection

To lower the wireless charge coil losses and leakage level of magnetic field for electromobile, a relay method with decentralised control logic based on active excitation detection by secondary side is proposed. It is guaranteed to only excite the primary coil below electromobile that raises charging requirement, to realise precise localisation and local power supply. The method fully multiplexes primary/secondary power coil and needs no additional sensing unit or centralised signal line. The active excitation detection circuit is configured as series connection-series connection compensating network and utilises its characteristic of frequency splitting to enhance intensity of detecting signal and avoid the overflow of secondary side's active excitation. A reasonable relay control flow is designed to reduce the power needed for detection and avoid conflict of simultaneous excitation of primary and secondary sides. Lastly, a simulation experiment was conducted to verify the feasibility of relay method proposed.
Oil phase displacement by acoustic streaming in a reservoir-on-a-chip

This article presents a reservoir-on-a-chip study of acoustic streaming as an enhanced oil recovery mechanism. Microfluidic devices with different porosities are fabricated using photolithography to serve as reservoir-on-a-chip micromodels. We use microparticle image velocimetry to characterize acoustic streaming-induced pumping as a function of frequency and amplitude. A scaling model applied to the velocity distribution is used to construct a state diagram that connects acoustic pressure to field frequency and amplitude. Optical video fluorescence microscopy is used to track the invasion of a water phase through the oil-saturated porous micromodel. Based on these measurements, we calculate the Blake number as a function of frequency to show that our system exhibits a narrow band dynamic response consistent with a system operating near resonance. Our observations are compared to a general model for Blake number as a function of frequency, porosity and voltage amplitude that was derived from a force balance model of the micromodel undergoing forced oscillation. The results from this paper are broadly applicable to systems beyond enhanced oil recovery, including separations, bio-analytical instruments, additive manufacturing and flow control.
The Role of IL-4 Signaling in CD8+ Innate-Like Lymphocyte Development.

Abstract 2161 The innate and adaptive arms of the immune system collaborate to protect the host against invading pathogens and perform immune surveillance against malignant transformation. As key effectors of the adaptive immune system, conventional T cells develop in the thymus and exit to the periphery as naive cells, requiring antigenic stimulation and subsequent differentiation to gain effector functions, such as cytokine secretion or cytolytic activity. In contrast to conventional T cells, non-conventional T lymphocytes possess characteristics of innate immune cells, such as expression of surface markers associated with activation/memory and acquisition of effector function during thymic development, and thus are termed innate-like lymphocytes (ILLs). Recently, an expanded population of CD8+ ILLs was identified in mice with a mutation in the T cell receptor signaling protein SLP-76 (SLP-76 Y145F mice). These CD8+ ILLs are characterized by expression of activation/memory markers CD44 and CD122, the expression of the T-box transcription factor Eomesodermin (Eomes) and rapid production of IFN-γ after ex vivo stimulation. The development of these CD8+ ILLs occurs in a cell-extrinsic manner and requires IL-4. We demonstrate that IL-4 is sufficient to upregulate Eomes expression in wild-type CD8 single-positive (SP) thymocytes in short-term in vitro culture and potentiate CD8+ ILL development in fetal thymic organ culture. Using phospho-flow cytometry, we find that CD8+ ILLs from SLP-76 Y145F mice have increased STAT6 and Akt activation vs. CD8+ non-ILLs. In CD8SP thymocytes deficient in STAT6, Eomes expression is not upregulated in response to IL-4. In addition, we demonstrate that pharmacologic inhibition of Akt in SLP-76 Y145F fetal thymic organ culture blocks CD8+ ILL development and also prevents IL-4 induced Eomes upregulation in WT CD8SP thymocytes. Importantly, we have identified CD8+ ILLs in human fetal thymocytes and umbilical cord blood and found that IL-4 is sufficient to up-regulate Eomes expression in these cells. Taken together, our data suggest that IL-4 signaling via STAT6 and Akt pathways is required for IL-4 induction of Eomes expression and CD8+ ILL development. Understanding signal transduction pathways required for CD8+ ILL development will provide insight into the development of this unique lymphocyte subset that sits at the interface between innate and adaptive immunity and has been identified in human umbilical cord blood. Disclosures: No relevant conflicts of interest to declare.
Assessment Research: An Assessment and Recommended Interventions

Assessment has been and will continue to be a major focus in school psychological practice and research. Although there is currently considerable variation in the content, quality, and orientation ...
Metastatic-free intervals and risk of breast cancer-specific mortality among patients with hormone receptor-positive breast cancer: A population-based analysis from the Surveillance, Epidemiology, and End Results registries.

e13034Background: Patients successfully treated for hormone receptor (HR)-positive early breast cancer remain at risk of recurrence and metastatic disease even after extended periods of disease-fre...
Anatomy and clinical relevance of sub occipital soft tissue connections with the dura mater in the upper cervical spine.

Background The upper cervical region is a complex anatomical structure. Myodural bridges between posterior suboccipital muscles and the dura might be important explaining conditions associated with the upper cervical spine dysfunction such as cervicogenic headache. This cadaver study explored the upper cervical spine and evaluated the myodural bridges along with position of spinal cord in response to passive motion of upper cervical spine. Methods A total of seven adult cadavers were used in this exploratory study. The suboccipital muscles and nuchal ligament were exposed. Connections between the Rectus Capitis Posterior major/minor and the Obliquus Capitis minor, the nuchal ligament, posterior aspect of the cervical spine, flavum ligament and the dura were explored and confirmed with histology. The position of the spinal cord was evaluated with passive motions of the upper cervical spine. Outcomes In all cadavers connective tissues attaching the Rectus Capitis Posterior Major to the posterior atlanto-occipital membrane were identified. In the sagittal dissection we observed connection between the nuchal ligament and the dura. Histology revealed that the connection is collagenous in nature. The spinal cord moves within the spinal canal during passive movement. Discussion The presence of tissue connections between ligament, bone and muscles in the suboccipital region was confirmed. The nuchal ligament was continuous with the menigiovertebral ligament and the dura. Passive upper cervical motion results in spinal cord motion within the canal and possible tensioning of nerve and ligamentous connections.
Investigating extreme ultraviolet radiation chemistry with first-principles quantum chemistry calculations

In extreme ultraviolet (EUV) lithography, chemistry is driven by secondary electrons. A deeper understanding of these processes is needed. However, electron-driven processes are inherently difficult to experimentally characterize for EUV materials, impeding targeted material engineering. A computational framework is needed to provide information for rational material engineering and identification at a molecular level. We demonstrate that density functional theory calculations can fulfill this purpose. We first demonstrate that primary electron energy spectrum can be predicted accurately. Second, the dynamics of a photoacid generator upon excitation or electron attachment are studied with ab-initio molecular dynamics calculations. Third, we demonstrate that electron attachment affinity is a good predictor of reduction potential and dose to clear. The correlation between such calculations and experiments suggests that these methods can be applied to computationally screen and design molecular components of EUV material and speed up the development process.
Food Intake During Cancer Therapy: A Systematic Review

Aim Conduct a systematic review of available evidence on food and beverage intake during cancer treatment. Objective Determine what food or beverages consumed during cancer treatment might prevent recurrence, subsequent malignancies, treatment-related toxicity, or death. Background Food and beverage intake, as well as weight status, can integrate with cancer treatment to mitigate treatment-related toxicities, support treatment success, and prevent recurrence. Yet, evidence-based recommendations are lacking. Methods We searched PubMed, Embase, and Cochran for research studies conducted within the last 10 years on food and beverage consumption during cancer treatment, with no restrictions on age or cancer type. Two reviewers independently extracted information on intervention type, diet, and outcomes; these data were confirmed by a third reviewer. Results Nineteen studies were selected from 1551 potential studies. Nine were randomized controlled trials, analyzing high protein diets, short-term fasting, low-fat diets, FODMAP diet, or comparing consumption of 1 specific food or nutrient, including Concord grape juice, onions, and fiber. The remaining 10 studies were observational or retrospective and tracked treatment symptoms, general dietary intake, or weight status as well as consumption of specific foods including nuts, coffee, sugar-sweetened beverages. Conclusions Available evidence suggests food can be effective at ameliorating cancer treatment-related toxicities and improving prognosis, but more research is needed.
Single bacterial resolvases first exploit, then constrain intrinsic dynamics of the Holliday junction to direct recombination

Homologous recombination forms and resolves an entangled DNA Holliday Junction (HJ) crucial for achieving genetic reshuffling and genome repair. To maintain genomic integrity, specialized resolvase enzymes cleave the entangled DNA into two discrete DNA molecules. However, it is unclear how two similar stacking isomers are distinguished, and how a cognate sequence is found and recognized to achieve accurate recombination. We here use single-molecule fluorescence observation and cluster analysis to examine how prototypic bacterial resolvase RuvC singles out two of the four HJ strands and achieves sequence-specific cleavage. We find that RuvC first exploits, then constrains the dynamics of intrinsic HJ isomer exchange at a sampled branch position to direct cleavage toward the catalytically competent HJ conformation and sequence, thus controlling recombination output at minimal energetic cost. Our model of rapid DNA scanning followed by ‘snap-locking’ of a cognate sequence is strikingly consistent with the conformational proofreading of other DNA-modifying enzymes.
A New Hemodynamic Profile Signaling Early Death on Left Ventricular Assist Device

Purpose To assess for a post left ventricular assist device (LVAD) hemodynamic profile predictive of early mortality. Methods A single center first-time, continuous-flow LVAD dataset was utilized for this analysis (n=505). Vasoactive drips and hemodynamics were collected at the following time points in all subjects with available data: pre-op, immediate post-op, and on post-operative days 1, 2, and 3 (n=325). Vasoactive intropes scores (VIS) were calculated at each time point. Trends before and after LVAD were computed and plotted using Locally Estimated Scatterplot Smoothing (LOESS), stratfied by death at 60 days post LVAD implantation. Mutivariate logistic regression and reciever operator curve analyses were performed to test the association between candidate variables and death at 60 days. Results The distinctive hemodynamic feature of patients who experienced death by 60 days was a failure to increase mean arterial pressure (MAP) from the time of leaving the operating room to post-operative day two accompanied by persistently elevated VIS (Figure). A model incorporating post-operative day two VIS, mean arterial pressure and right atrial pressure had an AUC of 78% to predict 60-day death. The group experiencing early mortality had higher measured cardiac indices, lower systemic vascular resistance, and higher right atrial pressures than patients who survived past 60 days, suggesting overlap between classic right ventricular failure and vasoplegia physiology. In this dataset, half of patients who met the criteria for vasoplegia also met criteria for right ventricular failure (21/41, 51%). Conclusion The failure to increase mean arterial pressure accompanied by high doses of inotropic and vasopressor support early after LVAD is highly associated with early mortality. This hemodynamic profile may be more unifying than existing right heart failure and vasoplegia definitions, which appear to have significant overlap. These findings require validation in an external dataset.
Thrombopoietin from hepatocytes promotes hematopoietic stem cell regeneration after myeloablation

The bone marrow niche plays a critical role in hematopoietic recovery and hematopoietic stem cell (HSC) regeneration after myeloablation. However, it is not clear whether systemic factors beyond the local niche are required for these essential processes in vivo. Thrombopoietin (TPO) is a critical cytokine promoting hematopoietic rebound after myeloablation and its transcripts are expressed by multiple cellular sources. The upregulation of bone marrow-derived TPO has been proposed to be crucial for hematopoietic recovery and HSC regeneration after stress. Nonetheless, the cellular source of TPO in stress has never been investigated genetically. We assessed the functional sources of TPO following two common myeloablative perturbations: 5-fluorouracil (5-FU) administration and irradiation. Using a Tpo translational reporter, we found that the liver but not the bone marrow is the major source of TPO protein after myeloablation. Mice with conditional Tpo deletion from osteoblasts or bone marrow stromal cells showed normal recovery of HSCs and hematopoiesis after myeloablation. In contrast, mice with conditional Tpo deletion from hepatocytes showed significant defects in HSC regeneration and hematopoietic rebound after myeloablation. Thus, systemic TPO from the liver is necessary for HSC regeneration and hematopoietic recovery in myeloablative stress conditions.
Injury Frequency and Characteristics in Adolescent and Adult Circus Artists: A Pilot Prospective Cohort Study.

Background Despite growing participation in circus arts, little is known about associated injuries. Understanding injury patterns is critical for developing interventions to decrease injury risk and guiding rehabilitation. Objective The purpose of this pilot prospective cohort study was to describe injury frequency and characteristics in adolescent and adult circus artists using a surveillance method derived from dance. Methods Participants included 14 adolescent [mean age 14.7 yrs (1.3); 100% female] and 10 adult circus artists [mean age 30.7 yrs (3.1); 60% female]. Circus training exposure (single session of one circus discipline) and injuries were tracked for 1 year using a dance-derived injury surveillance guideline. A regression analysis was run using total session exposures, age (in years), and years of circus experience as predictor variables for injury rate. Results Twenty-one of 24 participants completed the study. Forty-seven injuries were reported (53.2% time loss; 46.8% non-time loss). Joint injuries were most common for both groups. The injury rate per 1,000 exposures was 3 (95%CI 0.6-8.7) for adolescents and 13 (95%CI 6.9-22.01) for adults. The overall regression was significant (F(3,13)=6.66, p=0.006). The only significant predictor was age (beta=0.82, p=0.003). Total session exposures and years of circus experience had betas close to 0 (-0.11 and -0.04, respectively). Conclusion This pilot study comparing injuries in adolescent and adult circus artists found age but not exposure was predictive of injury risk. Use of a standardized injury surveillance guideline in circus, similar to the one used in this study, will provide greater insight into injury patterns by allowing between-study comparison.
Dreissenid metabolism and ecosystem-scale effects as revealed by oxygen consumption

Respiration rates of the quagga mussel (Dreissena rostriformis bugensis) were determined for the shallow and profunda morph phenotypes from in situ and laboratory experiments under a range of temperature (4–20°C), shell size, and food and oxygen availability conditions. Temperature-normalized oxygen consumption was significantly lower for the hypolimnetic profunda phenotype than for the shallow type. Mass-normalized respiration rates were inversely related to mussel size. Mussels adjusted their oxygen consumption in response to food enhancement and deprivation, lowering their respiration to a basal metabolic rate 18 hours after food deprivation. In response to decreasing ambient oxygen, quagga mussels exhibited first-order reaction kinetics, with mass-normalized respiration rate at a dissolved oxygen concentration of 0.002 mol L− 1 being 1% of that at saturation. Using published data on quagga mussel energy budgets and respiratory quotients, oxygen consumption rates were converted to organic carbon consumption rates. Using these values, along with data on mussel density and size frequency distribution, it is estimated that quagga mussels consume 54% of annual phytoplankton production, from 1.4–4.1 times the offshore annual settled organic carbon in the southern basin of Lake Michigan, and from 2.4–5.5% of offshore areal particulate carbon in the water column. Dreissenids appear to exert significant direct influences on benthic oxygen dynamics, and consume enough organic carbon to have a significant effect on energy flow in the Lake Michigan ecosystem.
Spatio-temporal Networks: Modeling, Storing, and Querying Temporally-Detailed Roadmaps

Given spatio-temporal networks (e.g., roadmaps with traffic speed reported as a time-series in 5 min increments over a typical day for each road-segment) and operators (e.g., network snapshot, shortest path or path evaluation), a spatio-temporal network model provides a computer representation to facilitate reasoning, analysis and algorithm design for important societal applications. For example, next generation routing services are estimated to save consumers hundreds of billions of dollars in terms of time and fuel saved by 2020. Developing a model for spatio-temporal networks is challenging due to potentially conflicting requirements of expressiveness and model simplicity. Related work in Time Geography models spatio-temporal movement and relationships via dimension-based representations such as space-time prisms and space-time trajectories. These representations are not adequate for many STN use-cases, such as spatio-temporal routing queries. To address these limitations, we discuss a novel model called time-aggregated graph (TAG) that allows the properties of the network to be modeled as a time series. This model retains spatial network information while reducing the temporal replication needed in other models, thus resulting in a much more efficient model for several computational techniques for routing problems. In this chapter, we discuss spatio-temporal networks as represented by time-aggregated graphs at a conceptual, logical, and physical level. This chapter also focuses on shortest path algorithms for spatio-temporal networks. We develop the topics via case studies using TAGs in context of Lagrangian shortest-path queries and evacuation route planning.
Ligand recombination to the alpha and beta subunits of human hemoglobin.

The rebinding of CO, O2, NO, methyl, ethyl, n-propyl, and n-butyl isocyanide to isolated alpha and beta chains and intact hemoglobin at pH 7, 20 degrees C was examined both during and after a 30-ns dye laser pulse. The resultant absorbance changes were analyzed in terms of a linear three-step reaction scheme: Hb + × in equilibrium with C in equilibrium with B in equilibrium with A or HbX, where A is the final bound state, and C and B are geminate states. Rate constants were assigned for each of the transitions in this mechanism using fitting procedures described previously for analyzing ligand rebinding to sperm whale myoglobin at room temperature (Gibson, Q. H., Olson, J. S., McKinnie, R. E., and Rohlfs, R. J. (1986) J. Biol. Chem. 261, 10228-10239). Five major conclusions were obtained. First, initial geminate recombination phases for the NO and O2 complexes of hemoglobin and its isolated subunits exhibit half-times equal to approximately 12 and approximately 440 ps, respectively. These values are in excellent agreement with more direct, picosecond measurements of the geminate recombination of HbNO (Cornelius, P. A., Hochstrasser, R. M., and Steele, A. W. (1983) J. Mol. Biol. 163, 119-128) and HbO2 (Friedman, J. M., Scott, T. W., Fisanick, G. J., Simon, S. R., Findsen, E. W., Ondrias, M. R., and MacDonald, V. W. (1985) Science 229, 187-229) following extremely short laser pulses. Second, the correspondence between our nanosecond measurements and the published picosecond data suggests strongly that the intrinsic photochemical yield of all ferrous, hexacoordinate heme complexes approaches one. Third, the major differences between the isolated alpha and beta chains involve the rate of ligand migration to the solvent, kC—X and the extent of recombination from the second geminate state, C, as measured by the ratio kC—B/kC—X. Fourth, for both isolated chains and intact hemoglobin, the rate and equilibrium constants for the formation of the initial O2 geminate state starting from ligand in the solvent (i.e. kX—B and KX—B) are 5-10 times greater than the corresponding parameters for the formation of the first CO geminate state. Fifth, the rate-limiting step for NO, O2, and isonitrile binding to hemoglobin and its isolated subunits is ligand migration up to the initial geminate state (i.e. kX—B). In the case of CO binding, both migration to state B and iron-ligand bond formation (kB—A) affect the overall, bimolecular association rate constant.
Stochastic Mean and Stochastic Volatility: A Four-Dimensional Term Structure of Interest Rates and its Application to the Pricing of Derivative Securities

In this paper a three-factor model of the term structure of interest rates is developed. In the model the future short rate depends on 1) the current short rate, 2) the short-term mean of the short rate, and 3) the current volatility of the short rate. Furthermore, it is assumed that both the short term mean of the short rate and the volatility of the short rate are stochastic and follow square-root process. The model is a substantial extension the seminal Cox-Ingersoll-Ross model of interest rates. A general formula for evaluating interest rate derivatives is presented. Closed-form solutions for prices of bond, bond option, futures, futures option, swap and cap are derived. The model can fit into the Heath-Jarrow-Morton arbitrage framework. The model is also useful for other practical purposes such as managing interest rate risks and formulating fixed income arbitrage strategies.
Can simulator immersion change cognitive style? Results from a cross-sectional study of field-dependence–independence in air traffic control students

Air traffic control (ATC) operations are critical to the U.S. aviation infrastructure, making ATC training a critical area of study. Because ATC performance is heavily dependent on visual processing, it is important to understand how to screen for or promote relevant visual processing abilities. While conventional wisdom has maintained that such abilities are largely innate and stable (i.e., not impacted by training or experience), recent research has begun to question this assumption. For example, intelligence has been thought to be stable, yet intelligence scores on the Ravens Progressive matrices (RPM) change over time. Because the RPM, like ATC, relies on visual pattern recognition, one hypothesized reason for these changes is the increased exposure to visually intensive technologies like videogames. Other constructs such as field-dependence/independence (FD-I) which, like the RPM, rely on visual pattern detection and are thought to be stable, might therefore also be affected by visual technology exposure. Two studies sought to examine the role of videogame play on FD-I and ATC simulation performance by ATC students at a Midwestern university. No benefits of videogame play were found. However, more fourth-year ATC students were field-independent (FI) than were first-year students and the general population. Findings suggest that exposure to the ATC training program over 4 years may result in more FI students, and that FD-I may not be stable. Possible explanations and implications are discussed.
Encouraging undergraduate research: a digital image processing approach

In recent years, undergraduate research has gained significant attention in many computer science departments. There have been efforts to identify courses that could support undergraduate research activities. Some courses such as image processing provides excellent research opportunities to undergraduate students. However, in small and comprehensive schools there is little or no image processing research to support the course. This paper presents an approach that encourages undergraduate research in image processing. Through a systematic planning, students develop toolkits that will be used in the instruction of the course. The developer of each toolkit is recognized as the toolkits are presented in the classroom or made available on the web page of the course. This provides a chance to current students to get to know about the work of their peers and will encourage them to produce similar toolkits or improve the existing ones. This approach encourages class participation and enhances the quality of students' research projects.
Climbing and falling dunes in Valles Marineris, Mars

[1] Multiple occurrences of “wall dunes” are found several kilometers above the Valles Marineris canyon floor. Dune slip face orientation and bed form morphologies indicate transport direction and whether the wall dunes are climbing dunes or falling dunes. On Earth, these types of dunes form in a unidirectional wind regime and are strongly controlled by the local topography. Newly acquired Mars Reconnaissance Orbiter (MRO) images and topography of the walls of Valles Marineris show similar sand dune morphologies, as wind blown sediment has interacted with local and regional topography. Primarily found in Melas and Coprates Chasmata, these climbing and falling dunes are relevant for understanding aeolian sediment flux, sediment sources, and wind directions. Falling dunes show photogeologic and thermophysical evidence of their sand being provided by adjacent outcrops.
Effect of Selenium and Vitamin E Deficiency on Nitrofurantoin Toxicity in the Chick

The acute toxicity of nitrofurantoin was studied in the young chick deficient in selenium (Se) and/or vitamin E (E). This new and potentially valuable animal model proved to be very sensitive to the toxicity of this nitro drug. The 48-hour LD50 for nitrofurantoin decreased from 148 mg/kg in the Se- and E-supplemented chicks to 53 mg/kg in Se- and E-deficient chicks. The addition of Se (0.10 ppm as Na2SeO3) alone, but not E (100 IU/kg diet as dl-alpha-tocopheryl acetate) reduced the toxicity of nitrofurantoin, so that the LD50 for the chicks given Se alone was the same as the LD50 for the E- and Se-fed chicks. Se and E deficiency significantly decreased the Se-dependent glutathione peroxidase and the plasma tocopherol levels. Hepatic glutathione content, hepatic catalase and superoxide dismutase were unchanged by the dietary treatments. However, a toxic dose of nitrofurantoin significantly decreased hepatic glutathione content over time. These data support the concept that the toxicity of this drug may be mediated in part by an oxidative stress generated by the futile reductive metabolism of the parent compound.
Application of GaAs pHEMT technology for efficient high-frequency switching regulators

The potential of GaAs pHEMT technology for low-voltage high-frequency power switching applications is discussed with a view towards their application for power supplies in portable electronic systems. The design and implementation of a 4.5V-to-3.3V buck converter power IC utilizing an enhancement mode pHEMT high side switch is demonstrated. The fabricated buck circuit is capable of operating at switching frequencies ranging from 100-MHz. While operating from a 4.5V supply a power efficiency of 87% is obtained at 100MHz when the output voltage is 3.3V and current is 500mA.
Efficient organic light emitting diodes and photodetectors

Summary form only given. A discussion of several approaches of employing organic semiconductors to achieve high performance devices is be the focus of this presentation. For example, we discuss means for obtaining extremely high efficiency organic light emitting devices (OLED) for displays, and organic photodetectors for power conversion and other detection applications, by effectively confining and capturing molecular excited states by appropriate and precision insertion of energy barriers in these devices. The first device to be discussed is an electrophosphorescent OLED. We show that by employing metallorganic phosphor molecules based on Pt or Ir, nearly 100% internal electroluminescent efficiency can be achieved. Using this approach, we have succeeded in demonstrating very high efficiency electrophosphorescent OLED emission in the red, green and blue spectral regions. Our most efficient devices demonstrated thus far are based on the green phosphor, (ppy)/sub 2/Ir(acac), with a maximum external quantum efficiency of 19/spl plusmn/1%, and luminous power efficiency of 60/spl plusmn/51 m/W.