cssi/SciSciGPT-SciSciNet huggingface dataset:
Ab Initio Computation of Energy Deposition During Electron Ionization of Molecules.

The dissociative ionization of molecules under electron impact forms the basis for analytical mass spectrometry of volatile compounds. It is also important in other situations, notably plasmas. Although qualitative theory for mass spectrometry was developed long ago, progress toward predictive theory has been slow. A major obstacle has been ignorance of the amount of energy deposited in the molecular ion, prior to its fragmentation. Here, we consider the Binary-Encounter Bethe (BEB) theory, which was originally developed for predicting total ionization cross sections. The energy deposition function constructed from BEB molecular-orbital cross sections compares well with the two comparable (e, 2e + ion) experimental measurements. When combined with experimental breakdown data from photoelectron-photoion-coincidence measurements, the BEB energy deposition function successfully reproduces library mass spectra for all but one of the six molecules studied here. This indicates that BEB molecular-orbital cross s...
On controlling the propagation characteristics of microstrip transmission lines using embedded micron-sized particles and static h-fields

Methods to control the propagation characteristics of printed microstrip transmission lines (TLs) has many uses in phased-array scanning, tunable apertures and reconfigurable antennas. In this paper, a unique method of changing the propagation along a microstrip TL with multiple magneto-static responsive structures (MRSs) is introduced. Each individual MRS is sub-wavelength in size and does not require a directly connected biasing circuit. In particular, the MRS consists of two parallel conducting planes separated by a dielectric material (forming a capacitor) and a cavity with micro particles that can be orientated/aligned (i.e., moved) using magneto-static fields. The particles can thus be manipulated using biasing fields such that the two conducting planes can then be connected and disconnected, changing the MRS state between capacitive (disconnected) and inductive (connected). The simulation and measurement results in this paper show that the effective permittivity of a 50Ω microstrip TL can be changed using MRSs.
FSH (Follicle-Stimulating Hormone)

Follicle-stimulating hormone (FSH) is a glycoprotein that is secreted by the pituitary gland and, in concert with luteinizing hormone, plays a central role in mammalian reproduction. FSH acts directly on the gonads in both sexes, binding to its receptor on the surface of target cells, initiating a cascade of molecular events beginning with the activation of specific signaling pathways and ending with the expression of gene products. The gene products, in turn, set in motion processes specific to each gonad. In the ovary, FSH stimulates folliculogenesis and steroidogenesis, which, in turn, prepare the female reproductive tract for fertilization, implantation, and pregnancy. In the testis, this gonadotropin plays a central role in testicular development and spermatogenesis. In both sexes, the products of FSH stimulation regulate the secretion of FSH either by modifying the release of the hypothalamic secretagogue, gonadotropin-releasing hormone (GnRH), or by acting directly at the pituitary gland (Fig. 1).
Epitaxy of CaF2/Si(111) and LiF/Ge(100)

The epitaxial growth of insulators on semiconductors is exemplified by the CaF2/Si(111) and LiF/Ge(100) systems, which are representative of the fluorite and rocksalt structures, respectively. High quality epitaxial films are grown, and are used to study the bonding at the interface (covalent versus ionic), surface states of the insulator, negative electron affinity, and band dispersions of the monolayer and thick film (band widening due to self-energy, band narrowing in the monolayer, band offset). The regrowth of semiconductors on epitaxial insulators is investigated via adsorption of Si2H6 and Si2Cl6 on CaF2/Si(111) activated by irradiation.
Martin's axiom and ordinal graphs: large

From set mapping theorems, Erd'os, Hajnal and Milner proved that every graph on a limit ordinal α<ωω+21 either contains an independentset of type α or an infinite path. In this paper, Martin's Axiom is used to extend the positive result to all limit ordinals less than the continuum. In another paper, under the assumption of Jensen's Diamond Principle, Baumgartner and Larson have constructed counter-examples for ordinals α with ωω+11<α<ω2
Women and Children without Shelter

Families are estimated to constitute approximately one-third of the homeless population in the United States and are the fastest-growing subgroup of homeless persons nationwide.1 This subgroup consists predominantly of female-headed households with children; the majority of family members are preschoolers. A network of emergency facilities has begun to emerge only recently despite the urgent needs of these families.
OPTIMAL DECISIONS UNDER UNCERTAINTY

ABSTRACT This paper presents a method for determining optimal decision under ‘uncertainty’ situations. A simple algorithm is developed to establish the probability function of all the input variables. The application of this algorithm is illustrated through an equipment justification example. Four variables-investment, life, salvage value and net annual cash flows-are used to analyze the desirability of investing in the equipment. The probability functions for each variable are obtained using the algorithm. Once the probability functions are determined, simulation is used to obtain the expected value and variance of the net present value. The expected value and the variance of net present value is used to establish the desirability of the investment.
Extraction of RNA from Recalcitrant Tree Species Paulownia elongata

Isolation of pure RNA is the basic requisite for most molecular biology work. Plants contain polyphenols and polysaccharides, which can interfere with isolation of pure RNA from them. Especially hardwood tree species like Paulownia elongata have surplus amount of RNA-binding alkaloids, proteins and secondary metabolites that can further complicate the process of RNA extraction. Paulownia elongata is a fast-growing tree species which is known for its role in environmental adaptability and biofuel research. Here we describe an economical, efficient and time-saving method (2 h) to extract RNA from leaf tissues of the tree Paulownia elongata. Lack of DNA contamination and good RNA integrity were confirmed using RNA Gel electrophoresis. The purity of RNA was confirmed using Nanodrop spectrophotometer that revealed an A260:A280 ratio of about 2.0. The purified RNA was successfully used in the downstream applications such as RT-PCR (Reverse Transcription PCR) and qPCR (quantitative PCR). This method could be used for RNA extraction from several other recalcitrant tree species.
Redo “Salvage” Vasectomy Reversal

If an initial reversal fails, then for selected patients a redo or salvage reversal may be a reasonable option with high success in skilled, experienced hand. Of course, there are unique challenges and limitations when attempting to reverse a failed first attempt, both with intraoperative decision-making and the technical aspects of the anastomosis. Redo reversals are more likely to be successful if there was a return of sperm into the ejaculate before becoming azoospermic, which is consistent with development of a post-op anastomotic stricture rather than originally performing an incorrect procedure. Of course, anyone that has performed redo reversals will tell you that redo salvage reversals are inherently more challenging and time-consuming because of the extensive scarring and distortion of normal anatomy.
Kosovo and Serbia: Loveless Marriage, Difficult Divorce

In Kosovo and Serbia, the ingredients of war were all salient: Yugoslavia’s breakup, Milosevic’s political ambitions as well as military capabilities, and ethnic nationalism. A last-ditch diplomatic push failed to prevent war, precipitating NATO’s second Balkan intervention and deployment. Now independent Kosovo is a product of luxury state-building, including NATO-led troops, UN administration, and a massive EU rule-of-law mission. But Kosovo’s sovereignty and democratic transition are still incomplete. Serbia’s postwar course was less internationalized, more organic, and more equivocal. Serbia lost control of Kosovo south of the Ibar River. Elections and popular protests removed Milosevic but failed to hold Serbian nationalism accountable. Belgrade aims for EU membership, but autocratic inclinations and strong ties with Russia threaten to divert it.
Practice modulates motor-related beta oscillations differently in adolescents and adults.

Key points Magnetoencephalography data were acquired during a leg force task in pre-/post-practice sessions in adolescents and adults. Strong peri-movement alpha and beta oscillations were mapped to the cortex. Following practice, performance improved and beta oscillations were altered. Beta oscillations decreased in the sensorimotor cortex in adolescents after practice, but increased in adults. No pre-/post-practice differences were detected for alpha oscillations. Abstract There is considerable evidence that there are motor performance and practice differences between adolescents and adults. Behavioural studies have suggested that these motor performance differences are simply due to experience. However, the neurophysiological nexus for these motor performance differences remains unknown. The present study investigates the short-term changes (e.g. fast motor learning) in the alpha and beta event-related desynchronizations (ERDs) associated with practising an ankle plantarflexion motor action. To this end, we utilized magnetoencephalography to identify changes in the alpha and beta ERDs in healthy adolescents (n = 21; age = 14 ± 2.1 years) and middle-aged adults (n = 22; age = 36.6 ± 5 years) after practising an isometric ankle plantarflexion target-matching task. After practice, all of the participants matched more targets and matched the targets faster, and had improved accuracy, faster reaction times and faster force production. However, the motor performance of the adults exceeded what was seen in the adolescents regardless of practice. In conjunction with the behavioural results, the strength of the beta ERDs across the motor planning and execution stages was reduced after practice in the sensorimotor cortices of the adolescents, but was stronger in the adults. No pre-/post-practice changes were found in the alpha ERDs. These outcomes suggest that there are age-dependent changes in the sensorimotor cortical oscillations after practising a motor task. We suspect that these noted differences might be related to familiarity with the motor task, GABA levels and/or maturational differences in the integrity of the white matter fibre tracts that comprise the respective cortical areas.
Accounting for the temperature dependence of 13C spin–lattice relaxation of methyl groups in the glycyl–alanyl-leucine model system under MAS with spin diffusion

The difficulties in quantitatively modeling the temperature dependence of spin–lattice relaxation in a model isotope-enriched peptide are explored as a prelude to obtaining dynamics parameters for motions in proteins from such measurements. The degree to which this can be handled by adding spin diffusion to a bath in standard rate matrix relaxation theory is studied using a small tri-peptide model system, glycyl–alanyl-leucine (GAL). We observe in this molecule that the relaxation of backbone carbons CO and Cα is not dominated by local fluctuations of the 13C–1H dipolar couplings, but rather by 13C–13C spin diffusion to nearby methyl relaxation sinks. A treatment of the methyl relaxation itself, which ignores 13C–13C spin diffusion effects back to the otherwise slowly relaxing bath, provides poor agreement between theory and experimental data obtained for the temperature dependence of the methyl relaxation rates. Closed form approximate spectral densities and relaxation rates for a methyl group during magic angle spinning are obtained to compute the needed transition rates. These average computed rates, in conjunction with an extended form of the Solomon equations, are found to adequately model the temperature dependence of the methyl relaxation rates when spin diffusion is included. The barrier to rotation for the alanine methyl in GAL is determined to be 3.5 kcal mol−1.
Fire Behavior Monitoring and Assessment in California with Multi-sensor Satellite Observations

The past two years became the most destructive wildfire years on record in the state of California, including the Mendocino Complex and wind-driven Camp fire in 2018. Strong "Santa Ana" winds fueled fast moving fires which burned into developed areas of Los Angeles in Southern California, while strong offshore "Diablo" winds drove a series of deadly fires Northern California wine country in 2017. These devastating wildfires killed hundreds of people, destroyed thousands of structures, led to evacuation of hundreds of thousands of people, and caused severe air quality problems in downwind urban centers far away from burned areas.
Behavioral effects in adult rats exposed to low doses of a phthalate mixture during the perinatal or adolescent period

Abstract Hormones influence neurodevelopment which can result in vulnerability to endocrine disruptors such as phthalates during both the perinatal period and adolescence. Using a rat model, we have previously shown that perinatal exposure to an environmentally relevant phthalate mixture at low doses results in cognitive flexibility deficits in adults and a reduction in neuron and synapse number within the medial prefrontal cortex. Here, we further examined the behavioral effects of exposure to an environmentally relevant mixture of phthalates at low doses during either perinatal development or adolescence. Using the elevated plus maze, adult females, not males, exposed to phthalates during adolescence showed indications of reduced anxiety-like behavior while perinatal exposed animals were unaffected. There was no effect of adolescent phthalate exposure on cognitive flexibility using the attentional set shift paradigm in either sex, unlike the impairments we have previously reported following perinatal exposure (Kougias et al., 2018b). Finally, there was no effect of phthalate exposure during either time frame on sensorimotor gating measured using prepulse inhibition. Environmentally relevant phthalate exposure during the perinatal period or during adolescence did not induce widespread changes in the adult behaviors measured here.
Observing 3-hydroxyanthranilate-3,4-dioxygenase in action through a crystalline lens.

The synthesis of quinolinic acid from tryptophan is a critical step in the de novo biosynthesis of nicotinamide adenine dinucleotide (NAD+) in mammals. Herein, the nonheme iron-based 3-hydroxyanthranilate-3,4-dioxygenase responsible for quinolinic acid production was studied by performing time-resolved in crystallo reactions monitored by UV-vis microspectroscopy, electron paramagnetic resonance (EPR) spectroscopy, and X-ray crystallography. Seven catalytic intermediates were kinetically and structurally resolved in the crystalline state, and each accompanies protein conformational changes at the active site. Among them, a monooxygenated, seven-membered lactone intermediate as a monodentate ligand of the iron center at 1.59-A resolution was captured, which presumably corresponds to a substrate-based radical species observed by EPR using a slurry of small-sized single crystals. Other structural snapshots determined at around 2.0-A resolution include monodentate and subsequently bidentate coordinated substrate, superoxo, alkylperoxo, and two metal-bound enol tautomers of the unstable dioxygenase product. These results reveal a detailed stepwise O-atom transfer dioxygenase mechanism along with potential isomerization activity that fine-tunes product profiling and affects the production of quinolinic acid at a junction of the metabolic pathway.
Right Heart Catheterization/Pulmonary Artery Catheterization Use In Cardiogenic Shock: A Friend Or A Foe? Insights from the Nationwide Readmissions Database

Background: The usefulness of the Right Heart Catherization/Pulmonary Artery Catheterization (RHC/PAC) has been long debated. Previous evidence has shown the lack of additive benefit of RHC/PAC use in various clinical settings. However, current evidence of RHC/PAC utility in the setting of cardiogenic shock (CS) is scarce. Methods: In the Nationwide Readmissions Database (NRD) using International Classification of Diseases, Tenth revision we identified 269,475 patient hospitalizations with cardiogenic shock between 2016-2017. We sought to evaluate the impact of RHC/PAC on in-hospital and readmission outcomes. Results: Approximately 25,840 patients received a RHC/PAC on index admission. The RHC/PAC group had significantly more comorbidities and higher AKI rates (73% vs 60.4%; p
The relationship between time-on-task in computer-aided instruction and the progress of developmental reading students at the University of Texas at Brownsville and Texas Southmost College

This research sought to determine what relationship exists between time-on-task in computer-aided instruction (CAI) using Destinations courseware and progress in reading ability of developmental reading students as indicated by the reading portion of the Texas Academic Skills Program (TASP) test. Time-on-task is the time during which a student actively works on Destinations activities, as recorded by the software management system. TASP, an exam required of all students in Texas public colleges, assesses reading, math, and writing skills. The population was made up of 482 students who took the TASP exam before and after CAI and who used Destinations CAI for remediation of reading skills. Null hypotheses were explored using Pearson correlation and linear multiple regression. The findings for the null hypotheses were the following: Ho1 - Correlation and linear regression correlation showed that time-on-task in Destinations CAI had no significant effect on the TASP scores of the population studied. Ho2 - Correlation and linear regression correlation showed that females made significantly better gains on the TASP test from CAI than males. Ho3 - Correlation and linear regression correlation showed that low-achiever students made no better gains on the TASP test from time-on-task in CAI than high-achiever students. Difference between the two group's gains was not statistically significant. Ho4 - The regression equations predicted the gain in TASP reading scores for less than 1% of the population studied. Only the regression equations for male students and female students separately were statistically significant. The researcher recommends replication of this study each semester to determine the effectiveness of CAI. Regular and systematic evaluation using pretest and posttest data will provide benchmarks so that the value of changes in instructional methods can be measured. This method of research can help to clarify questions that should be answered through other research methods.
Surgical Treatment of Pediatric Obstructive Sleep Apnea

Adenotonsillectomy (T&A) is the most common surgical treatment performed for children with obstructive sleep apnea (OSA) and is curative in the majority of children. However, those with severe OSA, obesity, metabolic disorders, or congenital disease often have persistent OSA following T&A. To address this issue, a number of surgical procedures have been developed to relieve obstruction in multiple anatomic locations including the nasal cavity, nasopharynx, oropharynx, hypopharynx, and larynx. The specific site of obstruction can be determined by physical exam as well as procedures such as cine magnetic resonance imaging or computed tomography and drug-induced sleep endoscopy. Given that children with OSA have an increased risk of perioperative complications, specific measures should be considered to prevent adverse events in this population. This chapter presents an overview of the surgical evaluation and management of children with OSA.
Mapping Patterns of Student Engagement Using Cluster Analysis

While there is little doubt that student engagement is important to academic outcomes ranging from grades to critical thinking skills and persistence, the evidence linking engagement to these academic outcomes is often mixed in higher education. To complement existing studies, our study took a multi-faceted look at engagement from behavioral, emotional, and cognitive engagement perspectives to identify differences among students in a narrow context—that of the engineering classroom. A convergent parallel mixed-methods approach used quantitative survey data collected from over 700 engineering students in seven engineering courses to identify different patterns of engagement in the classroom. Classroom observations generated qualitative data that were then analyzed to identify characteristics of classrooms that were associated with more frequent engagement. From survey-based student self-reports of five forms of engagement (attention, effort, and participation; positive and negative emotional engagement), two distinctly different patterns of engagement emerged from a k-means clustering analysis: more engaged and less engaged. Task value, instructor gender, nature of and incentive for active learning, and other factors varied among the courses studied, but no single strategy for student engagement emerged as consistently successful or unsuccessful.
A Flawed Dataset for Symbolic Equation Verification

Arabshahi, Singh, and Anandkumar (2018) propose a method for creating a dataset of symbolic mathematical equations for the tasks of symbolic equation verification and equation completion. Unfortunately, a dataset constructed using the method they propose will suffer from two serious flaws. First, the class of true equations that the procedure can generate will be very limited. Second, because true and false equations are generated in completely different ways, there are likely to be artifactual features that allow easy discrimination. Moreover, over the class of equations they consider, there is an extremely simple probabilistic procedure that solves the problem of equation verification with extremely high reliability. The usefulness of this problem in general as a testbed for AI systems is therefore doubtful.
Development of a Highly Portable Unmanned Surface Vehicle for Surf Zone Bathymetric Surveying

Francis, H. and Traykovski, P., 2021. Development of a highly portable unmanned surface vehicle for surf zone bathymetric surveying. Journal of Coastal Research, 37(5), 933–945. Coconut Creek (Florida), ISSN 0749-0208. This study reviews the design and subsequent effectiveness of a prototype autonomous survey vehicle built to collect data specifically in the surf zone. The breaking wave transitional zone between ocean and land is an important location to survey due to its impact on human infrastructure and vulnerability to the effects of climate change. However, this environment is notoriously difficult to survey due to its shallow depth and the turbulence of waves and currents. Three distinctive design choices were made at the beginning of the project with the goal of operating in the surf zone: First, the surface vehicle is light (15 kg) and fast (up to 7 m/s), both characteristics intended to enable one person to deploy it quickly and easily into the surf zone. Second, an electric motor that is connected to a jet drive eliminates a combustion engine's air intake, which can be contaminated with seawater and sand. The jet drive also removes any danger of spinning propellers and allows the vessel to run in very shallow water. Finally, the vessel has a foam bulb hatch cover that is watertight and allows the vessel to right itself if capsized by a wave. The outcome of this development effort is an unmanned vessel that has the maneuverability and power sufficient for surf zone operations and is self-righting. It runs off the waypoint based Ardupilot Mavlink program, which allows rapid transitions from autonomous modes to remote controlled modes and has a runtime of approximately 1.5 hours. The vessel has initially been used with a single beam echosounder and precision GPS to create highly detailed shallow water bathymetric maps. This study demonstrates this technique as a highly efficient method of creating bathymetric maps in coastal environments.
Extent of eosinophilic esophagitis predicts response to treatment

Background and study aim The clinical impact of eosinophilic esophagitis (EoE) limited to the distal esophagus (Lim-EE) vs. diffuse involvement (Dif-EE) is unknown. This study compared clinical characteristics and outcomes of Lim-EE vs. Dif-EE. Patients and methods This retrospective, single-center study of patients with EoE between December 2011 and December 2019 evaluated treatment response based on repeated pathology and/or clinical improvement using comparative statistics. Results 479 patients were identified (126 Lim-EE, 353 Dif-EE). Lim-EE patients had a higher incidence of endoscopically identified esophagitis (23.0 % vs. 14.7 %; P = 0.04), were older (50.8 [SD 16.2] vs. 46.4 [SD 15.3] years; P = 0.007), and were more likely to present with iron deficiency anemia (5.6 % vs. 1.7 %; P = 0.05), dyspepsia (15.1 % vs. 8.8 %; P = 0.06) or for Barrett’s surveillance (10.3 % vs. 3.7 %; P = 0.02). Patients with Dif-EE presented more frequently with dysphagia (57.2 % vs. 45.2 %; P = 0.02). Both groups had similar proton pump inhibitor (87.2 % vs. 83.3 %; P = 0.37) and steroid (12.8 % vs. 21.4 %; P = 0.14) use. Patients with Lim-EE had a better clinicopathologic response (61.5 % vs. 44.8 %; P = 0.009). On multivariate analysis, EoE extent predicted treatment response with an odds ratio of 1.89 (95 % confidence interval 1.13–3.20; P = 0.02). However, treatment response based only on repeat biopsy results showed no statistical difference between Lim-EE (52.5 %) and Dif-EE (39.7 %; P = 0.15). Conclusions Lim-EE may represent a distinct phenotype separate from Dif-EE, with more overlap with gastroesophageal reflux disease and better treatment response.
Selection of the Speed Command Distance for Improved Performance of a Rule-Based VSL and Lane Change Control.

Variable Speed Limit (VSL) control has been one of the most popular approaches with the potential of smoothing traffic flow, maximizing throughput at bottlenecks and improving mobility and safety. Despite the substantial research efforts in the field of VSL control, few studies have looked into the effect of the VSL zone distance from the point of an accident or a bottleneck. In this paper, we show that this distance has a significant impact on the effectiveness and performance of VSL control. We propose a rule-based VSL strategy that matches the outflow of VSL zone with the bottleneck capacity based on a multi-section cell transmission model (CTM). Then, we consider the distance of the upstream VSL zone as a control variable and perform a comprehensive analysis of its impact on the performance of the closed-loop traffic control system based on the CTM. We develop a lower bound that the VSL zone distance needs to satisfy in order to guarantee convergence to a desired flow and density, verified analytically and demonstrated using microscopic traffic simulations.
Interlaminar Shear Fatigue Characteristics of Fiber-Reinforced Composite Materials

In this investigation the interlaminar shear fatigue characteristics of three composite materials are examined: graphite-epoxy (HTS), boron-epoxy (AVCO 5505), and glass-epoxy (3M 1002 S/ply). Thick-laminate, short-beam shear specimens instrumented with electrical resistance strain rosettes were subjected to constant-amplitude sinusoidal loadings (positive/ positive, R = 0.1). Both residual strength and stiffness data are presented and trends in the fatigue life of these materials are established. The results of this preliminary investigation indicate that the fatigue characteristics of composite materials in the interlaminar modes differ significantly from fatigue characteristics in the fiber mode. While the residual strength of composite materials in the fiber mode has been shown to be only slightly reduced from the static strength after 10 6 cycles, the interlaminar shear strength is found to be diminished to approximately 50 percent of the static shear strength after 10 6 cycles. The shear stiffness, unlike the strength, is shown to be only slightly diminished over a 10 6 cycle lifetime. Finally, residual strengths are evaluated at 10 6 cycles for each material.
An Improved SAT Algorithm in Terms of Formula Length

We present an improved algorithm for the general satisfiability problem. We introduce a new measure, the l -value, for a Boolean formula $\cal F$, which is defined based on weighted variable frequencies in the formula $\cal F$. We then develop a branch-and-search algorithm for the satisfiability problem that tries to maximize the decreasing rates in terms of the l -value during the branch-and-search process. The complexity of the algorithm in terms of the l -value is finally converted into the complexity in terms of the total length L of the input formula, resulting in an algorithm of running time O (20.0911L ) = O (1.0652 L ) for the satisfiability problem, improving the previous best upper bound O (20.0926L ) = O (1.0663 L ) for the problem.
Real-Time Object Detection for Autonomous Robots

A new kind of robots whose characteristics, objectives and operational modes drastically differ from more conventional industrial robots is gaining increased interest. This new type of robots aims to achieve a high level of flexibility, adaptability, and efficiency for acting in environments designed for humans. To meet these demands, the mobile robots need lots of information about their surroundingsat different levels of abstraction, generally in real-time. In this paper a sensor concept is described containing symbolic and sub-symbolic information delivering the required data for all tasks. Based on this information the planning, navigation, and collision avoidance of the ARIADNE robots is done.
Characterization of the thermalness of a fissile system with a two-group diffusion theory parameter

In tabulating critical data, the hydrogen-to-fissile atom ratio (H/X) is commonly used to characterize the amount of moderation in a system. Though adequate in many cases, H/X does not account for the moderating contribution of other light nuclei contained in common uranium-moderator mixtures. This ratio also does not account for enrichment of the system, which affects the resonance absorption characteristics and, therefore, the moderating behavior of that system. To alleviate these problems, a two-energy-group diffusion theory analogy to the six-factor formula was applied to define a new parameter p/([eta][sub 2] [center dot] f[sub 2]), which describes the moderation characteristics or the thermalness' of a fissioning system and includes the effects of enrichment and the presence of moderators other than hydrogen. From an analysis of several low-enriched uranium systems with different moderators, it was found that the values of p/([eta][sub 2] [center dot] f[sub 2]) corresponding to minimum critical mass and volume tend to center in a narrower range than do the values of H/X for the same systems. Also, the thermalness parameter does not vary with the addition of a reflector and is applicable to systems with other than hydrogenous moderators. Based on these results, the thermalness parameter p/([eta][sub 2]more » [center dot] f[sub 2]) provides an effective means of characterizing moderated systems relative to optimum conditions.« less
OCO: Optimized Communication a Organization for Target Tracking in Wireless Sensor Networks

Wireless sensor networks (WSN) have affected various military and civilian applications. Target tracking is one of the top applications of WSNs. Efficient computation and energy dissipation are critical requirements for a WSN when used in target tracking. The goals are to maximize the networks lifetime while ensuring accuracy. Existing methods such as the LEACH-based algorithms suffer either complex computations or redundant data/sensor deployment. Those drawbacks result in inefficient energy use and/or computation overhead. Optimized Communication and Organization (OCO) is a method that provides self-organizing and routing capabilities. OCO ensures maximum accuracy, efficient energy dissipation, and low computation overhead. We have conducted simulation-based evaluations to compare the performance of OCO against LEACH and Direct Communication (DC), under various scenarios. This paper discusses OCO, the simulation set-up, the performance metrics, and the analysis of the results.
Matting through variational inpainting

While current matting algorithms work very well for some natural images, their performance is questionable in the presence of sharp discontinuities in the foreground and background regions. To counter the above problem, we propose to use variational PDE based inpainting techniques within the matting problem, that are largely successful in inpainting geometric features into unknown regions.
Spectroscopic probes of Escherichia coli glutamine synthetase. Rare earth ions by difference absorption.

Abstract 1. 1. Nd(III) and other tripositive lanthanide ions stimulate the biosynthetic activity of adenylylated Escherichia coli glutamine synthetase ( l -glutamate:ammonia ligase (ADP), EC 6.3.1.2) about 10–20% as well as Mn(II) at pH 6.50. With other forms of the enzyme and other assays, Nd(III) inhibits activity. 2. 2. Probe experiments with EPR and pulsed NMR, suggest that Nd(III) binds to the E11-(Mn2+)12n1 enzyme at the n2 sites to produce the E11-(Mn2+)121−(Nd3+)12n2 complex. 3. 3. Nd(III) bound to adenylated enzyme, compared to free ion, produces a difference absorption spectrum with relatively sharp peaks and troughs in the 300–600-nm region. 4. 4. This difference spectrum has been used to qualitatively evaluate the nature of the metal ion environment, and as a probe for studying perturbations by small molecules bound to the protein. The unique spectral changes induced by each substrate or modifier supports the conclusion that each possesses a unique binding site or mode of interaction with the protein.
Interdependent Expectations and the Spread of Currency Crises

In this paper we analyze how the mutual interdependence of private sector expectations influences the stability offixed exchange rate regimes in different countries. When countries trade with one another, the crisis probabilities are interdependent because monetary policy in each country affects welfare both at home and abroad. Wage setters react to a trading partner's imminent crisis, because a loss of international competitiveness changes their governments' optimal escape clauses. Thus, not only actual devaluations but an increasing crisis probability in one country may trigger currency crises elsewhere. We show that both fundamental weakness and spontaneous shifts in market sentiment may play a role in the transmission of currency crises.
Review of observations of ground diffusion in space and in time and fractal model of ground motion

We present evidences of the diffusive motion of the ground and tunnels and show that if systematic movements are excluded then the remaining uncorrelated component of the motion obeys a characteristic fractal law with the displacement variance dY^2 scaling with time- and spatial intervals T and L as dY^2 \propto T^(Alpha)L^(Gamma) with both exponents close to 1. We briefly describe experimental methods of the mesa- and microscopic ground motion detection used in the measurements at the physics research facilities sensitive to the motion, particularly, large high energy elementary particle accelerators. A simple mathematical model of the fractal motion demonstrating the observed scaling law is also presented and discussed.
Spectroscopic studies of Lewis acid-base complexes—I: Vibrational spectra and assignments for trimethylymine complexes of boron halides

Abstract Infrared and Raman spectra of 1:1 complexes of trimethylamine with boron trifluoride, boron trichloride and boron tribromide have been obtained in the solid state. Samples studied included those isotopically enriched in B 10 as well as those containing the natural isotopic ratio of B 11 to B 10 . On the basis of isotopic shifts and trends of frequencies within the series, vibrational assignments of the observed frequencies are proposed.
Suppression of Noxious Stimulus-Evoked Activity in the Ventral Posterolateral Nucleus of the Thalamus by a Cannabinoid Agonist: Correlation between Electrophysiological and Antinociceptive Effects

The CNS contains a putative cannabinergic neurotransmitter and an abundance of G-protein-coupled cannabinoid receptors. However, little is known about the function of this novel neurochemical system. Cannabinold agonists produce antinociception in behavioral tests, suggesting the possibility that this system serves in part to modulate pain sensitivity. To explore this possibility, the effects of the cannabinoid agonist WIN 55,212-2 on nociceptive neurons in the ventroposterolateral (VPL) nucleus of the thalamus were examined in urethane-anesthetized rats. After identification of a nociresponsive neuron, a computer-controlled device delivered graded pressure stimuli to the contralateral hindpaw. WIN 55,212-2 (0.0625, 0.125, and 0.25 mg/kg, i.v.) suppressed noxious stimulus-evoked activity of VPL neurons in a dose-dependent and reversible manner. Noxious stimulus-evoked firing was affected more than spontaneous firing. These effects were apparently mediated by cannabinoid receptors, because the cannabinoid receptor-inactive enantiomer of the drug (WIN 55,212-3, 0.25 mg/kg) failed to alter the activity of this population of cells. Administration of morphine (0.5 mg/kg, i.v.) produced effects that were very similar to those produced by the cannabinoid. WIN 55,212-2 (0.25 mg/kg, i.v.) failed to alter the responses of non-nociceptive low-threshold mechanosensitive neurons in the VPL WIN 55,212-2 produced antinociceptive effects with a potency and time course similar to that observed in the electrophysiological experiments, despite the differences in the anesthetic states of the animals used in these experiments. The antinociceptive and electrophysiological effects on VPL neurons outlasted the motor effects of the drug. Furthermore, the changes in nociceptive responding could not be attributed to changes in skin temperature. Taken together, these findings suggest that cannabinoids decrease nociceptive neurotransmission at the level of the thalamus and that one function of endogenous cannabinoids may be to modulate pain sensitivity.
Chasing fate and function of new neurons in adult brains

Neuron production, migration and differentiation are major developmental events that continue, on a smaller scale, into adult life in a wide range of species from insects to mammals. Recent reports of adult neurogenesis in primates, including humans, have led to explosive scientific and public attention. During the last two years, significant discoveries have revealed that the generation, recruitment and survival of new neurons in adult brains are governed by principles similar to those that shape the developing brain, such as neuronal death, sensory experience, activity levels, and learning. Similarly, many factors implicated in embryonic neurogenesis are increasingly found to regulate adult neurogenesis and survival as well. These findings now allow the first manipulations of the numbers of adult-generated neurons to address their potential behavioral function.
Kinetic shift in methane and allene ion fragmentation

Abstract The threshold photoelectron-photoion coincidence technique has been extended to study the H-loss fragmentation of methane and allene as a function of time. The allene ion breakdown curve in the region of parent to first fragment crossover shifted ca. 40 meV for a change in ion residence time of 4 μs. For methane no shift was observed for a charge in residence time of 2 μs. A detailed theoretical analysis of the breakdown curves in the crossover region has been made using the quasiequilibrium theory. The analysis included the effects of apparatus function, rotational energy distribution, internal thermal energy distribution and energy dependence of the rate constants. For both methane and allene, the agreement with the experimental results is very good. In the case of allene the agreement suggests that the C 3 H 4 + reactant ion has the allene structure rather than the propyne or cyclopropene isomeric forms. In addition it appears that the H-loss and ring-closing to form cyclopropenyl radical ion is a concerted process.
Bass-Tits minimization of automata, quotients of trees and diameters

Abstract Let X be a tree and let G = Aut ( X ) , Bass and Tits have given an algorithm to construct the ‘ultimate quotient’ of X by G starting with any quotient of X, an ‘edge-indexed’ graph. Using a sequence of integers that we compute at consecutive steps of the Bass–Tits (BT) algorithm, we give a lower bound on the diameter of the ultimate quotient of a tree by its automorphism group. For a tree X with finite quotient, this gives a lower bound on the minimum number of generators of a uniform X-lattice whose quotient graph coincides with G ⧹ X . This also gives a criterion to determine if the ultimate quotient of a tree is infinite. We construct an edge-indexed graph ( A , i ) for a deterministic finite state automaton and show that the BT algorithm for computing the ultimate quotient of ( A , i ) coincides with state minimizing algorithm for finite state automata. We obtain a lower bound on the minimum number of states of the minimized automaton. This gives a new proof that language for the word problem in a finitely generated group is regular if and only if the group is finite, and a new proof that the language of the membership problem for a subgroup is regular if and only if the subgroup has finite index.
The Influence of a Continuous Injection of Digitalis Tincture on Its Lethal Dose in Pigeons

Abstract A study of a wide dose range of digitalis tincture injected into igeons by a continuous injection method ingcates that with this method there is no significant change in the lethal dose at levels of from 0.0025 to 0.0226 cc./ Kg./min. during an experimental period of from forty‐two to 340 minutes.
Quasi-monotone images of certain classes of continua

Abstract Let ƒ be a continuous map from a compact metric continuum X onto a continuum Y. Then ƒ is quasi-monotone if, for each subcontinuum K of Y with nonvoid interior, ƒ-1(K) has a finite number of components and each is mapped onto K by ƒ. Examples of quasi-monotone maps are local homeomorphisms and other finite to one confluent maps. In the following all maps are assumed to be quasi-monotone from X onto Y. A theorem of L. Mohier and J.B. Fugate [1] says that if X is irreducible between two of its points then Y is also irreducible between two of its points. This result is generalized to the following theorem. If X is irreducible about a finite point set A then either Y is irreducible about ƒ(A) or there is a point y in Y such that Y is irreducible about {y}⋃ƒ(A⧹{α}) for each a in A. Another result is that if X is a continuum that is separated by no subcontinuum, i.e., a θ1-continuum, then Y is a θ1-continuum or is irreducible between two of its points.
Adjunctive Atropine Is Unnecessary during Ketamine Sedation in Children

Background: The prophylactic coadministration of atropine or other anticholinergics during dissociative sedation has historically been considered mandatory to mitigate ketamine-associated hypersalivation. Emergency physicians (EPs) are known to omit this adjunct, so a prospective study to describe the safety profile of this practice was initiated. Objectives: To quantify the magnitude of excessive salivation, describe interventions for hypersalivation, and describe any associated airway complications. Methods: In this prospective observational study of emergency department (ED) pediatric patients receiving dissociative sedation, treating physicians rated excessive salivation on a 100-mm visual analog scale and recorded the frequency and nature of airway complications and interventions for hypersalivation. Results: Of 1,090 ketamine sedations during the 3-year study period, 947 (86.9%) were performed without adjunctive atropine. Treating physicians assigned the majority (92%) of these subjects salivation visual analog scale ratings of 0 mm, i.e., “none,” and only 1.3% of ratings were ≥ 50 mm. Transient airway complications occurred in 3.2%, with just one (brief desaturation) felt related to hypersalivation (incidence 0.11%, 95% confidence interval = 0.003% to 0.59%). Interventions for hypersalivation (most commonly suctioning) occurred in 4.2%, with no occurrences of assisted ventilation or intubation. Conclusions: When adjunctive atropine is omitted during ketamine sedation in children, excessive salivation is uncommon, and associated airway complications are rare. Anticholinergic prophylaxis is not routinely necessary in this setting.
The Contribution of Institutional Theories to Explaining Decentralization of Natural Resource Governance

Governments are increasingly devolving governance of natural resources from central administrations to subnational levels. Researchers routinely document the complexity and contradictions of this process, but policy prescriptions and their underlying theoretical models remain overly simplified. Going beyond classical statements in the policy literature that emphasize interjurisdictional competition, we draw on recent developments in the multidisciplinary literature on institutional theory and the growing stock of research on natural resource governance. We develop an “institutional mediation” approach, which emphasizes the multilevel nestedness of rules and highlights the role of institutional incentives, contradictions, and complementarities in shaping how actors navigate decentralization reforms. Brief case studies of decentralization of forest governance in Bolivia and Uganda lend initial credence to the claims of this approach, and preliminary hypotheses for further research are proposed.
Force distribution at the hand/handle interface for grip and pull tasks:

The purpose of this experiment was to investigate how surface pressure distribution at the hand/handle interface changes during gripping and pulling and to enhance understanding of coupling between...
Effects of insulin on physical factors: Atherosclerosis in diabetes mellitus

Newton's laws of motion play a major role in blood flow. Inertia and conservation of momentum cause flow to separate at branches and curves in large blood vessels. Areas of separated flow in the arterial system are sites of atherogenesis. The place at which the separation ends, called the stagnation point, is the focus for plaque development. Pulsation of the arterial circulation causes the stagnation point to move downstream with each systole and upstream with each diastole. This movement generates forward and backward shearing force in the stagnation region as the separated flow migrates back and forth. Angular momentum, introduced into flowing blood with each heart beat and further enhanced by the asymmetry of origin of vessels branching from the aorta, generates a sidewise force component that is preserved during migration of the stagnation point. The sidewise force, added to the forward and backward shear stresses, creates an area of multidirectional shear stress under the migrating stagnation point that increases the permeability of the local endothelium. Blood is a complex fluid; it can generate greater shear stresses near the stagnation point than the simple fluids normally studied by fluid mechanicists. Blood is capable of retaining shear stress for short periods after it ceases to flow and extra work is required to establish its flow. In diabetes, reduced erythrocyte deformability further burdens flow onset. We are not yet able to establish whether the increase is only a few percent, or whether the burden is larger. Whatever its magnitude, diabetic modifications of the flow properties of blood, directly affect the size, location, and rate of development of atherosclerotic plaques.