cssi/SciSciGPT-SciSciNet huggingface dataset:
Regulation of cell division in the subapical shoot meristem of dwarf watermelon seedlings by gibberellic acid and polyethylene glycol 4000

The stimulatory effects of gibberellic acid (GA3) and the inhibitory effects of polyethylene glycol 4000 (PEG) on hypocotyl elongation and cell cycle kinetics in subapical pith cells of dwarf watermelon seedlings (Citrullus lanatus [Thunb.] Matsu and Nakai) were investigated. Mitotic indices (MI) were determined from direct counts of pith cells stained by a modified Feulgen technique. Labeling indices (LI) were determined from direct counts of labeled pith cells sampled 1.5 h after apical applications of3H-thymidine. Root application of 0.32 mM GA3 at 96, 120, or 144 h after sowing resulted in significant increases in both mitotic and labeling indices within 4.5 to 7.5 h following treatment. A single mitotic peak at 13.5 h occurred in all three treatment periods. Labeling peaks were often less defined than mitotic peaks; however, a relatively high proportion of labeled nuclei were usually observed between 7.5 and 9 h after GA3 treatment and at 16.5 h, the latter period coinciding with progression of cells into S phase from the peak period of mitosis. The results suggest that GA3 increases the proportion of rapidly dividing cells in the subapical meristem by increasing the probability that slowly cycling or nonproliferative cells in both 2C and 4C DNA states will enter the proliferative pool. The addition of PEG (200 g/l, ψ = 1.5 mPA) to the rooting medium of dwarf watermelon seedlings inhibited hypocotyl elongation and reduced both mitotic and labeling indices simultaneously within 4.5 h after treatment. Within 24–28 h after PEG treatment, mitotic and labeling indices approached 0. Seedlings transferred from PEG to either water or GA3 exhibited rapid recovery of cell division and hypocotyl elongation. Mitotic and labeling indices increased within 4.5–7.5 h into the recovery period in either water or GA3 and reached control values within 10.5 h. GA3 hastened the recovery from PEG-induced stress. It is concluded that water stress imposed by PEG 4000 causes arrest of cell division in meristematic cells of watermelon seedlings in both G1 and G2 periods. PEG and GA treatments resulted in only a partial and transitory synchronization of the cell cycle.
REDUCTION OF LIPID-SOLUBLE NITROXIDES IN CHO CELLS AND MACROPHAGE TUMOR CELLS

Abstract There is a need to understand the metabolism of nitroxides because of their usefulness in measurements in living cells of complex phenomena, such as biophysical properties, redox metabolism, and the concentration of oxygen at specific sites. As part of a systematic study of the metabolism of nitroxides in cells, the authors studied Chinese hamster ovary (CHO) cells and mouse macrophage tumor (M5076) cells, using a set of lipophilic nitroxides based on 5 doxyl stearate: the free acid, the methyl ester of the acid, and a phosphatidylcholine with two doxyl stearates esterified to the glycerol. The rates of metabolism of these nitroxides under anoxia different significantly as a function of both the type of cell and the type of nitroxide. The rates of reduction of the three lipophilic nitroxides depended on their localization. The rates of reduction were first order for all three lipophilic nitroxides, and the only products detected were the respective hydroxylamines. Effects of freeze-thawing and incubation temperature differed in the two cell lines. The authors conclude that the metabolism of nitroxides in different cell lines can be quite different. This may be especially important in understanding studies using nitroxides in living cells, functional organs, and in vivo.
A system mean void fraction model for predicting various transient phenomena associated with two-phase evaporating and condensing flows

The system mean void fraction model's principle virtue is its simplicity. The model converts the two-phase evaporating or condensing flow system into a type of lumped parameter system, generally yielding simple, closed form solutions in terms of the important system parameters. The particular applications of the model which are demonstrated in this paper are for a class of transient flow problems where complete vaporization or condensation takes place, and where the system mean void fraction can be considered to be time-invariant. This assumption uncouples the problem from the transient form of the momentum principle, an analytical simplification of considerable magnitude. The specific transients under consideration are caused by changes in the inlet flowrate. For evaporating flows, these transients are the effective liquid dry-out point, and the outlet flowrate of superheated vapor. For condensing flows, they are the effective point of complete condensation, and the outlet flowrate of subcooled liquid.
G protein selectivity is regulated by multiple intracellular regions of GPCRs.

GTP-binding protein coupled receptors (GPCRs) bind to a vast diversity of extracellular ligands to regulate a wide variety of physiological responses. Upon binding of extracellular ligands, these seven-transmembrane-spanning receptor molecules couple to one or several subtypes of G protein which reside at the intracellular side of the plasma membrane to trigger intracellular signaling events. Amid the large structural diversity at the intracellular regions of GPCRs, there are only 18 different subtypes of G protein belonging to four subfamilies. The question of how GPCRs select and activate a single or multiple G protein subtype(s) has been the topic of intense investigations. This review will attempt to summarize the available data on the structural determinants in GPCRs that regulate the selectivity of G protein activation. The available data suggest that G protein can be activated by structurally diverse cationic α-helical structures with no obvious homology in primary sequence. The selectivity of receptor-G protein coupling is maintained by a combination of two functional domains at the intracellular region. One is the ‘activation domain’ which can activate multiple G protein subtypes, while the other is the ‘selectivity domain’ which restricts the coupling to the desired signaling pathway(s). A slight change in the conformation at these two functional domains can affect the fidelity of G protein selectivity. This hypothesis can account for the vast structural diversity of GPCRs which link a fascinating variety of extracellular inputs, yet couple to a limited number of intracellular signaling pathways.
Prostaglandin F2α, oxytocin and progesterone secretion by bovine luteal cells at several stages of luteal development: Effects of oxytocin, luteinizing hormone, prostaglandin F2α and estradiol-17β☆

Bovine luteal cells from Days 4, 8, 14 and 18 of the estrous cycle were incubated for 2 h (1 × 105 cells/ml) in serum-free media with one or a combination of treatments [control (no hormone), prostaglandin F2α (PGF), oxytocin (OT), estradiol-17β (E) or luteinizing hormone (LH)]. Luteal cell conditioned media were then assayed by RIA for progesterone (P), PGF, and OT. Basal secretion of PGF on Days 4, 8, 14 and 18 was 173.8 ± 66.2, 111.1 ± 37.8, 57.7 ± 15.4 and 124.3 ± 29.9 pg/ml, respectively. Basal release of OT and P was greater on Day 4 (P<0.01) than on Day 8, 14 and 18 (rmOT: 17.5 ± 2.6 versus 5.6 ± 0.7, 6.0 ± 1.4 and 3.1 ± 0.4 pg/ml; P: 138.9 ± 19.5 versus 23.2 ± 7.5, 35.4 ± 6.5 and 43.6 ± 8.1 ng/ml, respectively). Oxytocin increased (P<0.01) PGF release by luteal cells compared with control cultures irrespective of day of estrous cycle. Estradiol-17β stimulated (P<0.05) PGF secretion on Days 8, 14 and LH increased (P<0.01) PGF production only on Day 14. Prostaglandin F2α, E and LH had no effect on OT release by luteal cells from any day. Luteinizing hormone alone or in combination with PGF, OT or E increased (P<0.01) P secretion by cells from Days 8, 14 and 18. However on Day 8, a combination of PGF + OT and PGF + E decreased (P<0.05) LH-stimulated P secretion. These data demonstrate that OT stimulates PGF secretion by bovine luteal cells in vitro. In addition, LH and E also stimulate PGF release but effects may vary with stage of estrous cycle.
Uniform damping control: discretization and optimization

Abstract This paper develops the control discretization and control optimization processes for the uniform damping of structures. A distributed uniform damping control is first shown to represent a first-order approximation to an associated globally optimal solution. This approximation is shown to be accurate for moderate to low levels of damping. The implementation of uniform damping control with discrete control forces is then demonstrated, using a subdomain approach, whereby a transformation of coordinates is carried out and a resulting subdomain polynomial expansion is truncated. Control laws are developed for one, two, and three discrete control forces per subdomain. Next, a steepest descent method is developed for the optimal assignment of control gains and the locations of the control forces. As a general rule the number of modes that can be uniformly damped is twice the number of control forces. The control discretization and associated optimization processes are illustrated via the control of a cantilever beam.
Usage of X-Ray CT for Empirical Transfer Functions in Dual Porosity Simulation

This research utilizes imbibition experiments and X-Ray tomography results for modeling fluid flow in naturally fractured reservoirs. Conventional dual porosity simulation requires large number of runs to quantify transfer function parameters for history matching purposes. In this study empirical transfer functions (ETF) are derived from imbibition experiments and this allows reduction in the uncertainness in modeling of transfer of fluids from the matrix to the fracture. The application of ETF approach is applied in two phases. In the first phase, imbibition experiments are numerically solved using the diffusivity equation. Usually only the oil recovery in imbibition experiments is matched. But with the advent of X-ray CT the spatial variation of the saturation can also be computed. The matching of this variation can lead to accurate reservoir characterization. In the second phase, the imbibition derived empirical transfer functions are used in developing a dual porosity reservoir simulator. The results from this study are compared with published results. The study reveals the impact of uncertainty in the transfer function parameters on the
Leprosy in the emergency department.

. Objectives: Los Angeles County—University of Southern California Medical Center, like many large urban hospitals, has a large immigrant population from regions of the world where leprosy is endemic. Emergency physicians (EPs) in these settings can expect to encounter leprosy patients. This study reviewed the emergency department (ED) course of patients with confirmed leprosy in an attempt to describe the most common presenting patterns so that future cases can be more easily recognized. Methods: This was a retrospective chart review of all patients followed in the Hansen's disease clinic. Demographics, leprosy type, clinical presentations to the ED, and medications were recorded. Results: Of the total number of patients (415), most were of Mexican (52%), Filipino (15%), Vietnamese (14%), and Chinese (5%) origin. Leprosy was classified as lepromatous (56%), borderline (40%), and tuberculoid (4%). There were a total of 118 ED visits by 74 patients. The mean age was 46 years, with 51% male and 49% female. Dermatologic (68%), neurologic (23%), and ophthalmologic (9%) complaints were the most common reasons for ED presentation related to leprosy. The EP did not elicit a history of leprosy in 34% of those patients followed in the leprosy clinic. The ED diagnosis of leprosy was made in 3 of 15 (20%) undiagnosed cases. Of the 63 patients prescribed medications in the leprosy clinic at the time of their ED visits, 22 (35%) ED charts did not report leprosy drugs. Conclusion: Patients with leprosy present to U.S. EDs, and new cases can be identified. Early recognition is important given leprosy's devastating consequences, major drug side effects of medications used for treatment, and improved prognosis with multidrug therapy. A history of leprosy and associated medications are often not documented in the ED chart, which may reflect a continued fear of stigmatization among these patients.
19 A Novel Approach to Residency Education in EMS: The MD‐PM Ambulance

Challenge: Indiana University EM residents have actively provided prehospital care as crew members on a hospital-based air ambulance service. This service functions as a secondary responder for high acuity patients who have already had first tier evaluation and care. First response, ground EMS experiences have been observational only as residents have ridden along with a two-paramedic team on an urban ambulance service for 24 hours during their residency careers. Resident understanding of first response care and challenges faced by initial EMS providers has been limited to that gleaned during their observational period. Solution: Most EM residencies do not provide opportunities for residents to function as first response providers. Therefore, we developed a Physician-Paramedic team to provide first response care within a busy metropolitan area. This two-member team operates within a “geozone” that includes a diverse patient population with both medical and trauma complaints. Unlike other residency ground EMS programs, the MD-PM truck responds primarily to all ambulance requests within their designated geozone and assists outside their designated geozone for multi-patient casualties in which a physician response would benefit patient care (fires, motor vehicle accidents, multiple gunshot victims). Residents on the MD-PM truck not only provide care equivalent to that expected of a nationally certified paramedic (IVs, drug administration, splinting, packaging), but also perform advanced skills such as RSI which is outside the scope of a traditional two-paramedic team. Immersion into the first response ground EMS system will provide valuable insight into the challenges of providing care outside of the hospital.
Effect of the detergent Tween-20 on the DNA affinity chromatography of Gal4, C/EBPα, and lac repressor with observations on column regeneration

C/EBPalpha, Gal4, and lac repressor, representing three different transcription factor homology families, were expressed as fusion proteins and used to characterize the effects of column aging, Mg2+, the nonionic detergent Tween-20, column loading, and bovine serum albumin on DNA-affinity chromatography. When lac-repressor-beta-galactosidase fusion protein is loaded onto a new DNA-Sepharose column, less elutes from a new column than one that has been used two or more times. Higher amounts of lac repressor, the Green Fluorescent Protein fusions with CAAT enhancer binding protein (C/EBPalpha) and Gal4, elute from the columns when 0.1% Tween-20 is added to the mobile phase. The amount of improvement found depends upon the transcription factor studied and the amount of the protein loaded on the column; lac repressor and Gal4 are eluted in higher amounts over a large range of protein loads while C/EBP shows the greatest effect at low protein loads. This detergent effect is seen when either Sepharose or silica is used for the stationary phase. Including bovine serum albumin in the mobile phase gives a similar though lesser improvement to that observed with Tween-20. Mg2+ or EDTA in the mobile phase gave similar chromatography for C/EBP; since EDTA protects columns from DNases, its inclusion in the mobile phase is preferred. After extended use, the DNA affinity columns no longer bind transcription factors and this is not due to losses of DNA from the columns. Two simple methods (sodium dodecylsulfate and KSCN) were developed to regenerate such worn out columns.
Regulation of pancreatic islet cell survival and replication by γ-aminobutyric acid

Aims/hypothesis Pancreatic islets have evolved remarkable, though poorly understood mechanisms to modify beta cell mass when nutrient intake fluctuates or cells are damaged. We hypothesised that appropriate and timely adjustments in cell number occur because beta cells release proliferative signals to surrounding cells when stimulated by nutrients and ‘bleed’ these growth factors upon injury.
The Knowledge Problem, Entrepreneurial Discovery, and Austrian Market Process Theory

Abstract Using a stylized model of the used car market, we extend the formal theory of the Austrian market process in three directions. First, we incorporate the knowledge problem and entrepreneurial alertness for the discovery of previously unknown information. Second, we allow for the possibility that entrepreneurs may make mistakes. Third, we describe the effect of entrepreneurial behavior on disequilibrium market adjustment. We give conditions under which an equilibrium exists for an Austrian market process with these elements and we analyze the stability properties of the equilibrium. Furthermore, we show that the model has interesting welfare properties—a commodity tax may increase or decrease welfare. Journal of Economic Literature Classification Number: D50
On Extension of “Heatline” and “Massline” Concepts to Reacting Flows Through Use of Conserved Scalars

A new formulation for extending the concept of heatlines and masslines to reacting flows through use of conserved scalars has been proposed. The formulation takes into account the distinct diffusion coefficients of different species. Results have been obtained for a number of two-dimensional nonreacting and reacting free shear flows under normal and zero gravity. For nonreacting flows, total enthalpy and elemental mass fractions have been used as the transported conserved scalars. For reacting flows, mixture fractions, defined as normalized elemental mass fractions and enthalpy, have been employed. The results show this concept to be a useful tool for obtaining better insights into the global qualitative picture of scalar transport for both nonreacting and reacting flows.
The neuropsychology of borderline personality disorder: a meta-analysis and review.

Abstract The neuropsychological profile of borderline personality disorder (BPD) is unclear. Past investigations have produced seemingly inconsistent results concerning precisely what neuropsychological deficits characterize the patient with BPD. A meta-analysis of 10 studies was conducted comparing BPD and healthy comparison groups on selected neuropsychological measures comprising six domains of functioning: attention, cognitive flexibility, learning and memory, planning, speeded processing, and visuospatial abilities. BPD participants performed more poorly than controls across all neuropsychological domains, with mean effect sizes (Cohen's d ) ranging from − 0.29 for cognitive flexibility to − 1.43 for planning. The results suggest that persons with BPD perform more poorly than healthy comparison groups in multiple neurocognitive domains and that these deficits may be more strongly lateralized to the right hemisphere. Although neuropsychological testing appears to be sensitive to the neurocognitive deficits of BPD, the clinical utility of these results is limited. Implications of these findings for future neurocognitive investigations of BPD are discussed.
Compositional verification using formal analysis for a flight critical system

Formal methods are seen as a cheaper and more exhaustive solution to the current expensive testing process used in the aviation industry. However, aviation systems are getting more and more complex. So, formal methods have no hope to address these systems unless some compositional argument is being made. In this talk, I will present the results of the effort led by NASA to demonstrate the use of formal methods and compositional verification for the V&V of safety requirements of a flight critical system. The talk will show how the formal arguments made at the component level are being composed into a system-level argument. The study is done on Simulink models for a quad-redundant flight control system for a transport class airplane.
Responding to the severe limitations of cross-sectional surveys: Commenting on Rong and Wilkinson’s perspectives

While a meta-analysis is necessary to test the claim that the logic dominates the majority of studies, most studies by academic scholars on thinking and actions by executives appear to rely on cross-sectional surveys that use self-reports by executives via scaled (e.g., strongly disagree to strongly agree) instruments whereby one executive per firm completes the instrument and data are collected for 50–500 firms. Useable response rates in these studies are almost always below 30% of the distributions of the surveys. While these studies are sometimes worthwhile for learning how respondents assess concepts and relationships among concepts, Rong and Wilkinson’s perspective on the severe limits to the value of such studies rings true: such surveys reveal more about executives’ sensemaking processes than the actual processes. The limitations of using one-shot, one-person-per-firm, self-reports as valid indicators of causal relationships of actual processes are so severe that academics should do more than think twice before using such surveys as the main method for collecting data – if scholars seek to understand and describe actual processes additional methods are necessary for data collection. The relevant literature includes several gems of exceptionally high quality, validity, and usefulness in the study of actual processes; identifying these studies is a useful step toward reducing the reliance on one-shot self-report surveys.
Optical Plasmon Properties of Co-Ag Nanocomposites Within the Mean-Field Approximation

The optical properties of multi-metal nanocomposites made from Cobalt (Co), and Silver (Ag) are analyzed theoretically within the mean field approximation, and experimentally verified using absorption spectroscopy. The experimental system was modeled as a thin layer composed of hemispherical nanoparticles formed by grains of Co and Ag in contact with air and the SiO $_{\text{2}}$ substrate. The main aspects of the absorption curve, such as the shape and spectral location of the localized surface plasmon resonance, are well captured by a simple self-consistent mixing model using a modified Maxwell-Garnett approach and the Milton lower bound.
Association of estrogen receptor 2 gene polymorphisms with obesity in women (obesity and estrogen receptor 2 gene).

Objective Few studies have examined the association between genetic variants of the estrogen receptor β (ESR2) and obesity in postmenopausal women.
Employer‐Employee Attitudes Regarding Union Security

The findings reported in this paper indicate employers and employees are generally unaware that the National Labor Relations Act (as amended) provides that the only obligation that can be enforced against an individual employee under a union shop contract is the obligation to pay dues and fees. Failure to understand the provisions of the law has serious implications for both employers and employees. Therefore, policy recommendations are advanced to deal with the problems engendered by the general lack of awareness of the provisions of the law.
Heat partitioning in metal-silicate plumes during Earth differentiation

Abstract We present an analytical model for core formation that includes both metal diapirs and liquid conduits and produces a superheated core. We start from the standard model of Earth formation consisting of accretion by planetesimal or planetary embryo impacts large enough to create global or local magma oceans. Our model consists of two main fluid dynamical structures: 1) large liquid metal diapirs and 2) narrow conduits with liquid silicate and small liquid metal droplets. We assume that transport of metal from a near-surface magma ocean to the growing core occurs within these structures. The release of gravitational potential energy from the descent of the metal is converted to heat through viscous dissipation, which is broadly distributed around the large liquid metal diapirs but localized in the conduit around the smaller metal droplets. This model gives an average core temperature during accretion and a post-accretion average core temperature for a broad range of impact histories and chemical quilibration assumptions. We consider three types of Earth accretion histories with impacts that are evenly spaced over 30 Ma. These include: 1) equal-sized impacts, 2) equal-sized impacts with a final Mars-sized impact, and 3) exponentially decreasing impact sizes with a final Mars-sized impact. Our preferred model is based on core–mantle chemical equilibrium estimates that correspond to a fractionation, f, the ratio of metal in the diapir to the total metal content in each impact of f = 0.64 and accretion history type 3. This model produces a post-accretion average core temperature that ranges from 5930 K to 5700 K for 8 to 90 impacts, respectively. The efficiency of the metal-silicate conduits, defined as the ratio of the heating of the core by the conduits to their potential energy released has an approximate value of 0.59 for our preferred model. The residual post-accretion structures include a basal magma ocean and a network of mantle conduits that may dictate the style of Hadean tectonics.
Having walked the path.

Harlan Casey's room was the farthest from the nurses' station at the end of the hallway, one usually saved for patients with contagious disease. Yet Harlan had clogged arteries and a failing heart.
A Matter of Time: The Importance of Tracking Reentry Into Foster Care Beyond One Year After Reunification

Reentry and reunification are key indicators of permanency in the federal Child and Family Services Reviews, and of overall child welfare system functioning. Reunification continues to be the preferred exit when possible; however, any analysis of reunification is incomplete without also determining whether those children later return to foster care. The current federal reentry measure is limited in that it tracks reentry into care for only up to 12 months after reunification. Should gauging the success of maintaining permanent reunification be limited to a 12-month follow-up time frame? Results indicate the importance of reentry analyses that extend beyond 12 months post-reunification.
On continuity of care in pediatric training.

McBurney et al1 report on an unusual approach to measuring continuity in a “continuity clinic,” in which residents follow assigned patients, primarily for well-child care. Their method assesses the proportion of all visits made by patients who are members of the residents’ panels. In primary care practice, in contrast, continuity would be the extent to which patients see their doctor for both well- and sick-child care, which is a very different measure. Primary …
De facto language policy in legislation defining adult basic education in the United States

This paper investigates the impact of differing interpretation of federal education policy in three different states. The policy, the Workforce Investment Act Title II, has defined the services provided for adult English language learners (ELLs) enrolled in Adult Basic Education programs in the United States since it was passed in 1998. At the time the Act was legislated, ELL success in school and work did not depend on their capacity to use online technology; consequently, WIA II addressed neither limitations nor support for digital literacy instruction. This paper describes how over time this created a lack of fit between the policy and an increasingly technological reality. This misalignment resulted in de facto language policy that limited learner access to English language instruction differently in each of the states, at times negatively impacting ELL ability to prepare for full participation in civic and economic life in the US. The paper includes a discussion about key changes evident in new legislation, the Workforce Innovation and Opportunities Act passed in 2014, which supplants WIA II, and how it may mitigate the issue of inadequate digital literacy support for English language learners.
Bipolar disorders in a community sample of older adolescents : prevalence, phenomenology, comorbidity, and course

ABSTRACT Objective The purpose of this study was to examine the prevalence, clinical characteristics, and mental health treatment services utilization of adolescents with bipolar disorders and manic symptoms. Method Structured diagnostic interviews were administered to a representative community sample of 1,709 older adolescents (aged 14 through 18 years). Results The lifetime prevalence of bipolar disorders (primarily bipolar II disorder and cyclothymia) was approximately 1%. An additional 5.7% of the sample reported having experienced a distinct period of abnormally and persistently elevated, expansive, or irritable mood even though they never met criteria for bipolar disorder ("core positive" subjects). The rate of manic symptoms in these subjects was similar to that reported in clinical samples, and the course of bipolar disorder was relatively chronic. Compared with adolescents with a history of major depression ( n = 316) and a "never mentally ill" group ( n = 845), the bipolar and core positive subjects both exhibited significant functional impairment and high rates of comorbidity (particularly with anxiety and disruptive behavior disorders), suicide attempts, and mental health services utilization. Conclusions These data highlight the clinical and public health significance of even the milder and subthreshold cases of bipolar disorder in adolescence.
Afanasy Nikitin’s Voyage Beyond Three Seas: An Orthodox Russian in Medieval India

AbstractAfanasy Nikitin was a Russian merchant who visited India in the 15th century and was not totally pleased with everything that he saw. And from this perspective, he might have been similar to Europeans who would visit India in the future. Still, there was a big difference. Nikitin might not like some Indian customs, but he was a man of the same Gemeinschaft culture as those Indians around him. And from this perspective, he was quite different from Europeans who were always alien to Indians.
Choice modeling of relook tasks for UAV search missions

This paper addresses human decision-making in supervisory control of a team of unmanned vehicles performing search missions. Previous work has proposed the use of a two-alternative choice framework, in which operators declare the presence or absence of a target in an image. It has been suggested that relooking at a target at some later time can help operators improve the accuracy of their decisions but it is not well understood how - or how well - operators handle this relook task with multiple UAVs. This paper makes two novel contributions in developing a choice model for a search task with relooks. First, we extend a previously proposed queueing model of the human operator by developing a retrial queue model that formally includes relooks. Since real models may deviate from some of the theoretical assumptions made in the requeueing literature, we develop a Discrete Event Simulation (DES) that embeds operator models derived from previous experimental data and present new results in the predicted performance of multi-UAV visual search tasks with relook. Our simulation results suggest that while relooks can in fact improve detection accuracy and decrease mean search times per target, the overall fraction found correctly is extremely sensitive to increased relooks.
Quantifying the impact of current and future tropospheric ozone on tree biomass, growth, physiology and biochemistry: a quantitative meta‐analysis

The northern hemisphere temperate and boreal forests currently provide an important carbon sink; however, current tropospheric ozone concentrations ([O₃]) and [O₃] projected for later this century are damaging to trees and have the potential to reduce the carbon sink strength of these forests. This meta-analysis estimated the magnitude of the impacts of current [O₃] and future [O₃] on the biomass, growth, physiology and biochemistry of trees representative of northern hemisphere forests. Current ambient [O₃] (40 ppb on average) significantly reduced the total biomass of trees by 7% compared with trees grown in charcoal-filtered (CF) controls, which approximate preindustrial [O₃]. Above- and belowground productivity were equally affected by ambient [O₃] in these studies. Elevated [O₃] of 64 ppb reduced total biomass by 11% compared with trees grown at ambient [O₃] while elevated [O₃] of 97 ppb reduced total biomass of trees by 17% compared with CF controls. The root-to-shoot ratio was significantly reduced by elevated [O₃] indicating greater sensitivity of root biomass to [O₃]. At elevated [O₃], trees had significant reductions in leaf area, Rubisco content and chlorophyll content which may underlie significant reductions in photosynthetic capacity. Trees also had lower transpiration rates, and were shorter in height and had reduced diameter when grown at elevated [O₃]. Further, at elevated [O₃], gymnosperms were significantly less sensitive than angiosperms. There were too few observations of the interaction of [O₃] with elevated [CO₂] and drought to conclusively project how these climate change factors will alter tree responses to [O₃]. Taken together, these results demonstrate that the carbon-sink strength of northern hemisphere forests is likely reduced by current [O₃] and will be further reduced in future if [O₃] rises. This implies that a key carbon sink currently offsetting a significant portion of global fossil fuel CO₂ emissions could be diminished or lost in the future.
A biomechanical analysis of initial fixation options for porous-tantalum-backed glenoid components.

Background Porous-tantalum (PT)-backed glenoid components have recently been developed to improve fixation and minimize the incidence of glenoid component loosening, which remains a key limiting factor in long-term survival in total shoulder arthroplasty. PT-backed glenoids promote bony ingrowth as a method of preventing glenoid loosening at the prosthesis-glenoid interface. The use of polymethyl-methacrylate (PMMA) cement for initial fixation may prevent osteointegration due to mechanical occlusion of the porous surface and the nonosteoconductive properties of PMMA. This study aims to investigate alternative fixation methods of PT-backed glenoids in a biomechanical investigation. Materials and methods Nine PT-backed monoblock glenoid components were implanted in a polyurethane bone substitute using either press-fit, PMMA cement, or calcium phosphate cement techniques. A control group of 3 all-polyethylene pegged glenoid components was implanted with PMMA. Glenoid and humeral head components were fixed to a biomechanical testing machine for testing according to ASTM Standard F-2028. The humeral head was translated ±1.5 mm along the superior-inferior axis for 50,000 cycles for characterization of glenoid rocking and inferior-superior translation. Results Glenoid compression and glenoid distraction followed similar patterns for PT-backed glenoids. Overall, the all-polyethylene cemented glenoid demonstrated superior fixation compared to all PT-backed groups throughout the test. Glenoids fixed with PMMA cement displayed more favorable initial fixation and resistance to glenoid motion throughout cyclic testing. Conclusion This study showed that among PT-backed glenoids, PMMA fixation provided an increase in stability during initial and final cycles compared to press-fit and calcium-phosphate fixation techniques. This improved stability may enhance the osteointegration of the implant.
Humic acids: Synthesis, properties and assimilation of yeast biomass

Abstract At pH 11, 22 ± PC, larger percentage-yields (%-yields) of hurnic acids (HAs) were obtained from catechol than from hydroquinone after 1 day, and the reverse after 4 days. Maximum %-yields were obtained at 3 days for catechol and 4 days for hydroquinone; both remained asymptotic thereafter at %-yields of 44% and 86% respectively. Percentage-yield was independent of initial concentration of reactants over the ranges 1.6–6.4 m catechol and 0.3–1.2 M hydroquinone, ranges that took into consideration solubility limitations. Significant increases in %-yields were obtained at each pH step from 7 to 11. and significant amounts of HAs derived from hydroquinone (H-HAs) but not HAs derived from catechol (C-HAs) were produced at pH 5 and pH 7. Energies of activation were .8786 and 12,134 Jdeg − mol − for catechol and hydroquinone respectively. Similar %-yields were obtained at 75° and 50°C, which were significantly higher than those obtained at 25°C. Without continuous shaking, %-yields of C-HAs were 2.0, 3.2 and 4.1 in darkness. Vis. and u.v. radiation respectively; constant %-yield, 26.8 ± 3.7 (SE), was obtained for H-HAs in darkness or under Vis. or u.v. Shaking did not increase %-yields of H-HAs, but significantly increased those of C-HAs—3.5-,3. 6- and 5.5-fold in darkness. Vis. and u.v. Hydrogen peroxide (0.5–3 M) had a stimulatory effect on synthesis of C-HAs during 24 h, with significantly increased production of C-HAs when present at 3 M. Production of H-HAs was inhibited throughout this range of H 2 O. C-HAs were less soluble than H-HAs at pH 7, had a higher molecular weight, and possessed a lower concentration of free radicals when formed after 1 day but a higher concentration when formed over 4 days. Significant amounts of biomass from Saccharomyces cererisiae (yeast) were assimilated in 4 days by H-HAs at pH 7.0. Evidence was not obtained to determine whether this could be attributed to a destructive effect of the H-HAs with subsequent uptake of both soluble degradation products and autolyzed soluble components of the yeast cells, or no destruction but mere uptake of the latter only. Reasons are provided to suggest that the induction of the initiation step of polymerization, or the maintenance of the propagation step, are fundamentally different for catechol and hydroquinone.
Highly water soluble multi-layer graphene nanoribbons and related honey-comb carbon nanostructures

Multi-layer graphene nanoribbons have been made highly water soluble (4.7 mg ml−1) and stable for the first time by repetitious derivatization with p-carboxyphenyldiazonium salt; similarly, single-walled carbon nanotubes (4.8 mg ml−1) and ultra-short carbon nanotubes (50 mg ml−1) can also be made highly soluble by the methodology.
Working Models of Attachment, Support Giving, and Support Seeking in a Stressful Situation

This study examined how working models of attachment to parents (assessed by the Adult Attachment Interview—AAI) and romantic partners (assessed by the Adult Attachment Questionnaire—AAQ) predicted spontaneous caregiving and care seeking in a stressful situation. Dating couples were videotaped while one partner (the man) waited to do a stressful task. Observers then rated each woman’s support giving and each man’s support seeking. The AAI and the AAQ independently predicted behavioral outcomes. Women with more secure representations of their parents and whose dating partners sought more support provided more support, whereas women with more secure representations of their parents whose partners sought less support provided less. Women who reported being more avoidantly attached to romantic partners provided less support than did less avoidant women, regardless of how much support their partners sought. Attachment orientations did not predict men’s support seeking.
The Genesis and Recognition of Anastomosed Fluvial Deposits: Data from the St. Mary River Formation, Southwestern Alberta, Canada

ABSTRACT Data from modern fluvial systems show that the term anastomosed is best reserved for suspended-load systems with multiple channels and very low slope that flow in regions where the hydrograph has a seasonal peak. The interchannel areas are topographic lows relative to the channel hanks and are places where crevasse-splay, marsh, and lacustrine sedimentation occurs. Channel geometry is intrinsically a function of the rate of sediment partitioning; the coarsest sediment is deposited in the channels, on the levees, and in proximal splay complexes, whereas the silts and clays are deposited on the rest of the floodplain. Extrinsic controls on the formation of these systems are geological and climatic. They include a source of suspended sediment and a highly seasonal water budget. Preservat on of anastomosed fluvial deposits requires a mechanism for maintaining very low depositional slopes over geologic time scales. Data from the St. Mary River Formation in southwestern Alberta show that the stratigraphic equivalents of these rivers are ribbon sandstone bodies encased in thin sandstones, shales, and siltstones. The total distribution of facies, rather than proof of simultaneous flow in multiple channels, can be used to interpret correctly a deposit as anastomosed fluvial. Although anastomosed fluvial deposits form in a variety of tectonic settings, they are apparently most common in foreland basins because these basins provide suitable source rocks and thrusting as a mechanism that can maintain the low depositional slopes over millions of years. The mutual interaction among source rock, climate, and subsidence, all of which play critical roles in forming and preserving these distinctive fluvial deposits, allows inferences to be drawn regarding paleoclimate and paleoslope that may help constrain models of basin evolution.
A fast expected time algorithm for Boolean matrix multiplication and transitive closure

A probabilistic algorithm is presented to calculate the Boolean product of two n × n Boolean matrices using an expected number of elementary operations of 0(n2). Asymptotically in n, almost all pairs of matrices may be multiplied using this algorithm in 0(n2+e) elementary operations for any e > 0.
Active ghrelin levels across time and associations with leptin and anthropometrics in healthy ache Amerindian women of Paraguay.

Active (acylated) ghrelin is a peptide hormone secreted primarily by the stomach, positively associated with fasting, orexigenic, and promotes growth hormone secretion. It is therefore important to energy intake management. The objective of this pilot research was to (1) compare active ghrelin with previous measurements of leptin and anthropometrics; (2) assess the consistency of active ghrelin across time in this population; (3) extend our understanding of potential population variation in active ghrelin. Two serum samples separated by 10 days at the same time between meals were collected from healthy Ache women (n = 12, mean age 32.2 ± 14.0 SD) to determine consistency over time, associations with leptin, and anthropmetric values. Mean active ghrelin was 72.9 ± 23.0 pg/ml, highly correlated (r2 = 0.95, P < 0.0001) between collections, and showed no paired mean differences (P < 0.18). There was no significant correlation with leptin, age, or anthropometric measures. Active ghrelin appears to be consistent over time in this population, perhaps reflecting regimented meal schedules and less interpopulation variation compared to leptin. Am. J. Hum. Biol., 2008. © 2007 Wiley-Liss, Inc.
Correction of Symptomatic Coronary Arteriovenous Fistula by Coil Embolization

The successful percutaneous closure by coil embolization, of a right coronary artery to superior vena cava fistula in an elderly adult, abolished the symptoms caused by the significant left to right shunt. (J Interven Cardiol 1993; 6:315–318)
Interpretation of Doppler Shifts in the Zodiacal Light Spectrum

Reay and Ring1 have recently presented measurements of Doppler shifts in the spectrum of the evening zodiacal light obtained in the plane of the ecliptic. They compare the data with the assumption that the interplanetary dust particles are in direct circular orbits, the number density of dust particles varying with heliocentric distance, r, as r−β, where β = 3. The agreement between theory and observations is imperfect; nevertheless, their suggestion about the dust density is of great importance to an understanding of the origin of the zodiacal dust cloud. We have therefore tried to obtain an improved fit to these observations by using a more general distribution of the orbital parameters of the dust particles in the hope of drawing a more definite conclusion concerning the value of β.
Degree of cardiac fibrosis and hypertrophy at time of implantation predicts myocardial improvement during left ventricular assist device support

Abstract Background: There have been increasing reports of cardiac improvement in heart failure patients supported by left ventricular assist devices (LVADs i.e.), including a number of patients who have tolerated removal of the device without the benefit of cardiac transplant. In the current study, we retrospectively investigated echocardiographic and histologic changes in patients supported by LVADs ( n = 18). The goal of our study was to determine if the degree of cardiac fibrosis and myocyte size in pre-implant biopsies could predict myocardial improvement as assessed by improvements in ejection fraction (EF) during LVAD support. Methods: We determined total collagen content in myocardial biopsy specimens by a semi-quantitative analysis of positive Picro-Sirius Red-stained areas and myocyte size measurements by computerized edge detection software. Results: During LVAD support, 9 of the 18 patients (Group A) were distinguished by significant improvement in ejection fraction (pre Conclusions: We found that the patients who demonstrated the greatest improvements in EF during support had less fibrosis and smaller myocytes at the time of device implantation. We propose that tissue profiling a patient's pre-implant biopsy for fibrosis and myocyte size may allow stratification in Stage IV heart failure and may predict myocardial improvement during LVAD support.
An isothermal amplification reactor with an integrated isolation membrane for point-of-care detection of infectious diseases

A simple, point of care, inexpensive, disposable cassette for the detection of nucleic acids extracted from pathogens was designed, constructed, and tested. The cassette utilizes a single reaction chamber for isothermal amplification of nucleic acids. The chamber is equipped with an integrated, flow-through, Flinders Technology Associates (Whatman FTA®) membrane for the isolation, concentration, and purification of DNA and/or RNA. The nucleic acids captured by the membrane are used directly as templates for amplification without elution, thus simplifying the cassette's flow control. The FTA membrane also serves another critical role—enabling the removal of inhibitors that dramatically reduce detection sensitivity. Thermal control is provided with a thin film heater external to the cassette. The amplification process was monitored in real time with a portable, compact fluorescent reader. The utility of the integrated, single-chamber cassette was demonstrated by detecting the presence of HIV-1 in oral fluids. The HIV RNA was reverse transcribed and subjected to loop-mediated, isothermal amplification (LAMP). A detection limit of less than 10 HIV particles was demonstrated. The cassette is particularly suitable for resource poor regions, where funds and trained personnel are in short supply. The cassette can be readily modified to detect nucleic acids associated with other pathogens borne in saliva, urine, and other body fluids as well as in water and food.