cssi/SciSciGPT-SciSciNet huggingface dataset:
Integrated microfluidic helium discharge photoionization detectors

Abstract Helium discharge photoionization detectors (HDPIDs) have been of increasing importance for detection of highly volatile compounds in gas chromatography (GC) and portable gas monitoring systems. The high ionization energy of these detectors (13.5–17.5 eV) allows for detection of virtually all compounds of interest, offering a distinct advantage compared to conventional PIDs, which can only detect compounds with ionization potentials below 10.6 (or 11.7, if using argon) eV. However, many current designs are bulky, power intensive, or helium intensive, restricting their usage to benchtop laboratory use. We recently developed a miniaturized HDPID that has low power and helium consumption, and small footprint. While offering suitable performance for portable GC applications, this design relies on hand assembly of silicon and Pyrex glass pieces, reducing fabrication yield, robustness, and repeatability. The current work improves on this prior device using an integrated, microfabricated μHDPID chip along with in-house designed plasma excitation and readout circuits. The μHDPID is characterized using permanent gases, light hydrocarbons, and formaldehyde, achieving low detection limits better than 10 pg, high linearity, rapid response time, short warm-up time, and high repeatability among devices. This integrated on-chip gas sensor offers advantages in ease of fabrication, yield and robustness, and repeatability. Therefore, it can be broadly used in portable GC for various applications.
The Consumption of Advertising: Attention & Ad Content

This paper develops an equilibrium framework to structure informational and non-informational content for ad messages in various market settings. The novel element in this framework is in assessing the viewer’s individual incentives to attend to elements of an ad relative to some other, non-ad-viewing activity. We prescribe ad content strategies across various (i) market factors, (ii) advertising goals, and (iii) ad formats (skippable versus non-skippable). Our framework classifies many advertising content strategies observed in practice. First, an advertiser can structure content to induce curiosity for continued viewing, a tactic prevalent in clickbait ads and “mystery ads”. Second, skippable ads have a lower return to non-informational content relative to non-skippable ads and explains the industry perception that ads on digital media are of lower copy quality than traditional ads. Finally, skippable ads are better suited for less ambitious advertising goals, such as brand awareness, when attention-spans are shorter. This latter result justifies the value proposition for the skippable format used by digital media platforms, such as YouTube and Facebook.
Evaluation of Cutinase Activity of Various Industrial Lipases

Eight industrial lipases were tested for cutinase activity on apple (Malus pumila cv. Golden Delicious) cutin and compared with cutinase from the fungus Fusarium solani f. sp pisi. The analysis of released cutin monomers was performed by normal-phase h.p.l.c with an evaporative light-scattering detector. Calibration curves of cutin monomers were established for quantification of cutinolytic activity of the industrial lipases. The pH optimum for cutinase activity of the lipase preparations was approx. 8.0. A high concentration of detergent was necessary for expression of cutinase activity. The most active lipase was found to be Amano PS-800, which was capable of hydrolysing 16% of apple cutin.
Coupling numerical simulation and machine learning to model shale gas production at different time resolutions

Abstract Reservoir simulation is the most robust tool for simulating gas production from the desorption controlled and hydraulically fractured shale reservoir. Incorporation of the created massive hydraulic fractures explicitly into the simulation model is the major challenge during the model development and computation phases. A pattern recognition-based proxy model is our proposed technique to overcome the aforementioned problem by modeling time successive shale gas production at the hydraulic fracture cluster level at different time resolutions (Short-, medium- and long term). Ensemble of multiple, interconnected adaptive neuro-fuzzy systems create the core for the development of the shale proxy models. In this approach, unlike reduced order models, the physics and the space-time resolution are not reduced. Instead of using pre-defined functional forms that are more frequently used to develop response surfaces, a series of machine learning algorithms that conform to the system theory are used. A history-matched Marcellus shale gas pad with six horizontal laterals and 169 clusters of hydraulic fracture is used as a base case for shale proxy model development. Additionally, several realizations are defined in order to capture the uncertainties inherent in the shale simulation model. The proxy model is validated using a blind simulation run that is not used during the model development process. The developed shale proxy model re-generates the simulation results for methane production for 169 clusters hydraulic fracture in a second with high accuracy (
Hormonal Control of Morphogenesis in Cultured Tissues

Several aspects of the hormonal control of morphogenesis have been reviewed recently (1–5). As a result, a comprehensive review of this topic would appear to be redundant at the present time. A better use for these pages would appear to be the presentation of a critical evaluation of the idea that two hormones, auxin and cytokinin, represent the primary morphogens in higher plants. To narrow the topic somewhat, I intend to confine my attention to studies which have been conducted with cultured tissues, where much of the important work has been done. Although it is by no means an established fact, the bulk of this work supports the hypothesis that auxin and cytokinin represent the primary signals for organogenesis and cytodifferentiation in higher plants.
Factors Affecting Root Exudation Ii: 1970–1978

Publisher Summary Root exudates are involved in chelation and solubilization of nutrients, in soil aggregation, and in effects on the pH of the soil solution. This chapter reviews contributions to the knowledge and understanding of the factors affecting root exudation that have been published during the period 1970–1978. Because there has been increasing interest in seed exudation and reevaluation of seedling root exudates in comparison with seed exudates, the factors affecting seed exudation are discussed in the chapter. Many of the investigations that identify exudates and factors affecting exudation have involved seedling plants in axenic culture. Results have been useful in demonstrating the multifaceted aspects of exudation of a variety of compounds and in quantifying exudation for defined conditions. Information on exudation of plants in the field comes from studies of changing populations of microorganisms and 14 CO 2 incorporation and subsequent exudation of elaborated metabolites into soil.
Development communication expectations in occupational contexts: A Comparison of U.S. and foreign graduate students

Abstract This study focuses on the communication approaches used by experts in development. In line with recent “paradigm shift” issues, this study asks whether foreign and U.S. graduate students have inculcated alternative communication approaches instead of, or in addition to, the predominant “top to bottom” communication approach in their occupational communication roles. A total of 24 foreign and 23 U.S. graduate students from various departments at the University of Washington were asked to describe their expected communication with contact groups above, at the same and at lower status levels. All graduate students showed a marked tendency to exhibit “top to bottom” approaches with contacts of lower status and alternative communication approaches (i.e., bottom to top or interactive) only with peers. Few differences were found between U.S. and foreign, but those that were found were attributed to differing societal and occupational structures. Discussion focused on the lack of a coherent communication approach showing inculcation of more user oriented approaches suggested by the “paradigm shift.”
p-Version two-dimensional curved beam element using piecewise hierarchical approximation for laminated composites

A three node two-dimensional laminated composite curved beam finite element formulation for linear static analysis is presented where the displacement approximation for the laminate is piecewise hierarchical and is derived based on p-version. The displacement approximation for the element is developed by establishing a hierarchical displacement approximation for each lamina of the laminate and then by imposing interlamina continuity conditions of displacement at the interfaces between the laminas. The approximation functions and the nodal variables for each lamina are derived directly from the Lagrange family of interpolation functions of order pξand pη. This is accomplished by first establishing one-dimensional hierarchical approximation functions and the corresponding nodal variable operators in the ξ and η directions for the three and one node equivalent configurations that correspond to pξ+1 and pη+1 equally spaced nodes in the ξ and η directions and then taking their products. The nodal variables for the entire laminate are derived from the nodal variables of the laminas and the interlamina continuity conditions of displacements. The element formulation ensures C0 continuity of displacement across the interelement as well as interlamina boundaries.
Bits-per-joule capacity of energy-limited wireless ad hoc networks

We develop a framework to evaluate the capacity of wireless ad hoc networks in which the energy supply of the nodes is the primary resource constraint. The measure of capacity in such networks is the "bits-perJoule capacity" that specifies the maximum number of bits that the network can deliver per Joule of energy in the network. First, for the one-to-one traffic model in which each node generates traffic for exactly one other randomly picked node, we demonstrate that the bits-per-Joule capacity grows with the number of nodes. Second, we demonstrate that sparse and locally-computed network topologies can approximate this capacity. Third, for ad hoc-cellular "hybrid" networks in which the node set is partitioned between an ad hoc part and a cellular part, we demonstrate under three representative traffic models, that the ad hoc topology performs far better than the cellular topology.
Sensory experience modifies the short-term dynamics of neocortical synapses.

Many representations of sensory stimuli in the neocortex are arranged as topographic maps. These cortical maps are not fixed, but show experience-dependent plasticity1,2. For instance, sensory deprivation causes the cortical area representing the deprived sensory input to shrink, and neighbouring spared representations to enlarge, in somatosensory3, auditory4 or visual cortex5. In adolescent and adult animals, changes in cortical maps are most noticeable in the supragranular layers at the junction of deprived and spared cortex6,7,8,9. However, the cellular mechanisms of this experience-dependent plasticity are unclear. Long-term potentiation and depression have been implicated10,11,12, but have not been proven to be necessary or sufficient for cortical map reorganization. Short-term synaptic dynamics have not been considered. We developed a brain slice preparation involving rat whisker barrel cortex in vitro. Here we report that sensory deprivation alters short-term synaptic dynamics in both vertical and horizontal excitatory pathways within the supragranular cortex. Moreover, modifications of horizontal pathways amplify changes in the vertical inputs. Our findings help to explain the functional cortical reorganization that follows persistent changes of sensory experience.
Review of Charles T. Tart’s Book: The End of Materialism: How Evidence of the Paranormal Is Bringing Science and Spirit Together

Tart believes that the big five, his referral to telepathy, clairvoyance, precognition, psychokinesis, and psychic healing, are well supported by scientific evidence. Tart reviews this evidence, but wants to go to the next step: to consider other paranormal phenomena, and to look at the issue of what these phenomena mean in a philosophical sense (his best bet). You can find this book at Amazon: The End of Materialism: How Evidence of the Paranormal Is Bringing Science and Spirit Together .
Comparative assessment of performance differentials for male-and female-owned small accounting firms at the beginning and end of a ten year period

The objective of this study was to determine whether the performance gap over a period of ten years between male- and female-owned small accounting firms has converged utilizing a resource-based framework to assess performance. The relevant assets for these firms included human, organizational, and entrepreneurial capital. An analysis of covariance (ANCOVA) was used to determine whether the gender productivity gap converged over this period of time. The response rates were 30 percent and 23 percent respectively for the 1993 and 2003 investigations. An analysis of the data indicates several important findings that (1) a performance gap exists when measured by gross revenues between male- and female-owned small accounting firms, (2) this performance gap has converged after ten years, and (3) the performance gap as measured by the ratio of net profit to sales indicates that female-owned small accounting firms do better than male owned accounting firms.
Computational MHD on lagrangian grids

Conservative, multidimensional, Lagrangian, staggered-grid hydrodynamics algorithms are well known[l]. Here, these principles are extended to include magnetic fields in the discretized momentum and energy equations. A magnetic vector potential, A, formulation is centered on edges so that the divergence law, ▽ · B = 0 is maintained to round-off error. The magnetic field is cell-centered. Magnetic forces from Maxwell's stress tensor are expressed in terms of the field and geometric quantities. This assures momentum and energy conservation. The method is expressed in 3D, but is generalizable to 1 or 2D. Resistive diffusion of the madoes not serve to straighten the azimuthal magnetic field lines [2]. gnetic field is handled by implicit time differencing and is solved by preconditioned, conjugate gradient methods. Multi-material, Z-pinch, test-problems are shown.
Multiple comparisons and the p-value in evaluation

When evaluating a technique or tool, multiple comparisons are usually made. Physically this is extremely easy with modern computers. Interpretation can be another question. This is an important situation with respect to the observed p-value or level of statistical significance. The evaluation of questions for medical research demonstrates the problems which arise.
Validation of Nitrogen-13-Ammonia Tracer Kinetic Model for Quantification of Myocardial Blood Flow Using PET

Positron emission tomography has been shown to provide quantitative estimates of myocardial blood flow using 13N-ammonia and 15O-water. In a validation study, myocardial blood flow was noninvasively determined in 11 open-chest anesthetized dogs using dynamic positron emission tomography. The radiopharmaceuticals 13N-ammonia and 15O-water were intravenously administered and measurements were carried out at rest and following pharmacological vasodilation to assess blood flow over a range from 53 to 580 ml/100 g/min. Quantification of blood flow based on tracer kinetic modeling of 13N-ammonia data correlated closely with myocardial blood flow determined by microspheres (y = 0.944 x +7.22, r = 0.986) and with the 15O-water injection technique y = 1.054 x -15.8 (r = 0.99). The use of 13N-ammonia with positron emission tomography enables the accurate quantification of myocardial blood flow. Using this technique, uncomplicated study protocols simplify the measurement procedures while providing excellent qualitative and quantitative information.
Using the Model AQP Database to Develop Effective CRM Training

The Advanced Qualification Program (AQP) represents a dramatic shift in philosophy as to how best to train flight crews to handle the set of demands placed on them when operating a complex aircraft in a complex operational environment. The AQP process encourages a thoughtful and comprehensive evaluation of what constitutes the flying job and how training can be designed to provide effective and efficient coverage of important training issues. Through the process of designing a Model AQP Database to support AQP curriculum development, the concept of an event as a tool for supporting a situational approach to crew training was developed. This paper discusses the event concept, how events are designed, and the benefits gained by using events as the basic tool for developing a curriculum.
Houston's Emerging Exposure between African Americans and Whites: Evidence of Spatial Assimilation or Place Stratification?

The persistent finding of a racial gap in residential attainment between African Americans and whites has led to a critique, which argues that spatial assimilation theory does not explain the residential segregation of African Americans, even though it explains segregation for other groups. That critique is typically based on analyses of cross-sectional data, which do not take into account demographic context. In this paper, I examine demographically adjusted exposure scores for educational categories of race and ethnic groups in Houston, Texas, between 1970 and 2000. I find that starting in 1980 higher status African Americans achieved greater spatial assimilation. My findings suggest that analyses that rely on demographically appropriate measures and trend data indicate that spatial assimilation theory is relevant to changes in the residential mobility of African Americans. Copyright © 2013 John Wiley & Sons, Ltd.
Development of a short-period superconducting undulator at APS

A planar superconducting undulator (SCU) with a period of 15 mm is under development at the Advanced Photon Source (APS). The intended users require a photon energy that can be tuned from 19 to 28 keV for inelastic X-ray scattering studies. The SCU design consists of two low-carbon-steel cores that are positioned above and below the beam chamber. There are 20 turns of NbTi/Cu superconducting (SC) wire within a coil cross section of 4.3 /spl times/ 4.0 (w /spl times/ h) mm/sup 2/. At a pole gap of 8 mm, the necessary average current density in the coil will be about 1 kA/mm/sup 2/ to achieve a peak field of 0.8 T on the beam axis. The design and fabrication progress of a 12-period prototype SCU are presented, and some challenging requirements are discussed.
Blood Clotting Enzymology

During the past quarter century perhaps no single phenomenon has attracted so much attention in biology and medicine as blood clotting. It plays a role in numerous clinical conditions where it was not taken into account previously. Knowledge of the basic mechanisms recently passed through a tumulous stage of growth, but is now delineated in terms of simple enzymology. Most of the components have been obtained in purified form. There are three main events: the formation of autoprothrombin C (F-Xa, thrombokinase), the formation of thrombin, and the formation of fibrin. Prothrombin itself is a more marvelous protein than was predicted. It is a protein aggregate that contains the precursor of thrombin, the precursor of autoprothrombin C, as well as accessory protein. When blood coagulation is initiated by tissue injury, large amounts of autoprothrombin C activity arise in the presence of calcium ions and tissue thromboplastin. When there is no tissue injury, small amounts of autoprothrombin C are produced by platelet cofactor I (F-VIII, AHF) which functions with the lipids of platelets. Autoprothrombin C is the enzyme which produces thrombin activity, and being a part of the prothrombin aggregate it is in close proximity to the specific bond(s) that must be split to get thrombin activity. Although autoprothrombin C alone is sufficient to produce thrombin, the reaction is greatly accelerated by plasma Ac-globulin (F-V), lipids from platelets, and calcium ions. The acceleration produced by components functioning in pairs and relays makes possible the essential integration with the anatomic location of resources. Tissue materials pair with plasma resources to produce autoprothrombin C, and then they pair with another plasma component (Ac-globulin) to make autoprothrombin C function. In the absence of tissue injury, platelet materials pair with plasma resources to produce autoprothrombin C, and then platelets again work with another plasma component (Ac-globulin) to support the function of autoprothrombin C. Platelets are essential because their lipids are needed for the formation of autoprothrombin C, as well as for accelerating its function. Whatever involves platelets can be the stimulus to accelerate blood clotting; this includes Hageman factor. Platelets are the true point of beginning for the first step in blood clotting and are involved in the second and third. Vitamin K deficiency, or counteraction of Vitamin K by Dicumarol reduces prothrombin synthesis by the liver. As a consequence the precursor of thrombin, the precursor of autoprothrombin C, and the accessory protein of the molecular aggregate which constitutes prothrombin is reduced in concentration. It has been found possible to produce abnormal conditinos experimentally and have relatively more of the precursor of thrombin released to the blood than is normally associated with the precursor of autoprothrombin C. Up to the point of incorporation to form a single prothrombin molecule, the synthesis of subunits proceeds by separately operating mechanisms.
GINSENOSIDE RB1 REGULATES CHAT, NGF AND TRKA MRNA EXPRESSION IN THE RAT BRAIN

Ginsenoside Rb1 (Rb1), a saponin of North American ginseng (Panax quinquefolium L.), has been found to exert beneficial effects on memory and learning, putatively through its actions on the cholinergic system. In situ hybridization studies show that Rb1 increases the expression of choline acetyltransferase and trkA mRNAs in the basal forebrain and nerve growth factor mRNA in the hippocampus. Other neurotrophins (brain-derived neurotrophic factor, neurotrophin-3), genes encoding neuropeptides (preproenkephalin, preprotachykinin) and amyloid protein precursor were also studied, but no significant change was observed. These findings support the specificity of the effects of Rb1 on certain aspects of the cholinergic and neurotrophic systems.
Trends in prostate-specific antigen testing from 1995 through 2004.

Background The utility of the prostate-specific antigen (PSA) test to screen for prostate cancer has been widely debated for several years. Whether PSA testing rates have changed during this period of controversy is not well known. Methods We examined the National Ambulatory Medical Care Survey (1995-2004) of visits to primary care providers by healthy men aged 35 years or older. We examined visits by calendar year and compared the years 2000 through 2004 with the years 1995 through 1999. We also examined visits by men in the overall population and in particular subgroups. Results Primary care physicians ordered PSA tests in 4.7% of all visits in 1995 and in 7.0% of all visits in 2004 ( P = .03). In multivariate analysis, the odds of a primary care physician ordering a PSA test during any clinic visit increased 8% (odds ratio [OR], 1.08; 95% confidence interval [CI], 1.04-1.12; P P = .003). Comparing the period 2000-2004 with the period 1995-1999, the odds of PSA testing increased in nearly all subgroups but most dramatically in black men (OR, 2.3; 95% CI, 1.4-3.8; P = .002) and in men 35 through 49 years of age (OR, 1.8; 95% CI, 1.3-2.6; P = .001). Conclusion In a nationally representative sample, we found that despite the lack of clear evidence of benefit, PSA testing for prostate cancer screening has increased dramatically, especially among black men and younger men.
Smoothened Regulates Activator and Repressor Functions of Hedgehog Signaling via Two Distinct Mechanisms

The secreted protein Hedgehog (Hh) plays an important role in metazoan development and as a survival factor for many human tumors. In both cases, Hh signaling proceeds through the activation of the seven-transmembrane protein Smoothened (Smo), which is thought to convert the Gli family of transcription factors from transcriptional repressors to transcriptional activators. Here, we provide evidence that Smo signals to the Hh signaling complex, which consists of the kinesin-related protein Costal2 (Cos2), the protein kinase Fused (Fu), and the Drosophila Gli homolog cubitus interruptus (Ci), in two distinct manners. We show that many of the commonly observed molecular events following Hh signaling are not transmitted in a linear fashion but instead are activated through two signals that bifurcate at Smo to independently affect activator and repressor pools of Ci.
Traits for selection of paraprofessionals for behavior- modification consultation training.

This paper aims at specifying the characteristics associated with success in behavior-modification consultation. Consultants were undergraduate paraprofessionals who completed a program in consultation. Discussed are the training procedures, the psychometric and other selection measures, and statistical results when comparing the selection tools with different criteria.
Serial time-encoded amplified imaging for real-time observation of fast dynamic phenomena

Ultrafast real-time optical imaging is used in many areas of science, from biological imaging to the study of shockwaves. But in systems that undergo changes on very fast timescales, conventional technologies such as CCD (charge-coupled-device) cameras are compromised. Either imaging speed or sensitivity has to be sacrificed unless special cooling or extra-bright light is used. This is because it takes time to read out the data from sensor arrays, and at high frame rates only a few photons are collected. Now a UCLA team has developed an imaging method that overcomes these limitations and offers frame rates at least a thousand times faster than those of conventional CCDs, making this perhaps the world's fastest continuously running camera, with a shutter speed of 440 picoseconds. The technology — serial time-encoded amplified microscopy or STEAM — maps a two-dimensional image into a serial time-domain data stream and simultaneously amplifies the image in the optical domain. A single-pixel photodetector then captures the entire image. Ultrafast real-time optical imaging is used in diverse areas of science, but conventional imaging devices such as CCDs are incapable of capturing fast dynamical processes with high sensitivity and resolution. This imaging method overcomes these limitations and offers frame rates that are at least 1,000 times faster than those of conventional CCDs. The approach is applied to continuous real-time imaging of microfluidic flow and phase-explosion effects that occur during laser ablation. Ultrafast real-time optical imaging is an indispensable tool for studying dynamical events such as shock waves1,2, chemical dynamics in living cells3,4, neural activity5,6, laser surgery7,8,9 and microfluidics10,11. However, conventional CCDs (charge-coupled devices) and their complementary metal–oxide–semiconductor (CMOS) counterparts are incapable of capturing fast dynamical processes with high sensitivity and resolution. This is due in part to a technological limitation—it takes time to read out the data from sensor arrays. Also, there is the fundamental compromise between sensitivity and frame rate; at high frame rates, fewer photons are collected during each frame—a problem that affects nearly all optical imaging systems. Here we report an imaging method that overcomes these limitations and offers frame rates that are at least 1,000 times faster than those of conventional CCDs. Our technique maps a two-dimensional (2D) image into a serial time-domain data stream and simultaneously amplifies the image in the optical domain. We capture an entire 2D image using a single-pixel photodetector and achieve a net image amplification of 25 dB (a factor of 316). This overcomes the compromise between sensitivity and frame rate without resorting to cooling and high-intensity illumination. As a proof of concept, we perform continuous real-time imaging at a frame speed of 163 ns (a frame rate of 6.1 MHz) and a shutter speed of 440 ps. We also demonstrate real-time imaging of microfluidic flow and phase-explosion effects that occur during laser ablation.
Parents who walk away.

Denton Johnson’s mother is often brusque and insulting. She has never been on time for appointments. She calls me “Lantos” rather than “Dr. Lantos,” as if I’m some not very popular kid she knows on the schoolyard. “Hey Lantos,” she’ll say, “I need a refill on his Albuterol.” Her son, Denton, has cerebral palsy, mental retardation, and failure to thrive. For years, I’ve been trying to convince her that he is not eating enough and that he needs a gastrostomy tube. For years, she has responded by describing to me, in detail and in an increasingly weary tone of voice, just how much she feeds him and how much he eats at home, “Lantos, Lantos,” she’ll say, “He loves to eat. Last night he had meatloaf, and mashed potatoes, and greens.” He is fourteen years old and weighs forty pounds. The school nurse keeps sending me notes suggesting that I should report the family to the Child Protection Service for medical neglect. I could. They often miss appointments. Mom sometimes has a whiff of alcohol on her breath. Denton is malnourished. But I doubt if much would happen. She could beat that system cold. She’d show up for her court date well-dressed. She’d describe how much she feeds him. She’d promise to do better. She can be very believable. I know. For years, I’ve made “contracts” with her: if he doesn’t gain a pound in the next month, we’ll send him to the surgeon for a g-tube. “Ok, Lantos, Ok,” she’ll say. Sometimes, she would manage to get him to gain weight, and then she’d return to clinic with a smug grin, aware of her success even before we weigh him. Other times, she would miss the next appointment and not show up for months. Then, when she’d reappear, Denton would have lost weight again, and she would have an elaborate and heart-wrenching story. She was in the hospital getting a hysterectomy. Her mother died. They were kicked out of their house. I like her. She loves Denton. And I admire her. She is very good at what she does. She cares for him and advocates for him, according to her values. He looks happy. He is just really small. Last year, after years of this, I told her that if she didn’t take him for a gastrostomy, I could no longer be her
Optimal payment of mortgages

This article provides a borrower's optimal strategies to terminate a mortgage with a fixed interest rate by paying the outstanding balance all at once. The problem is modelled as a free boundary problem for the appropriate analogue of the Black-Scholes pricing equation under the assumption of the Vasicek model for the short-term rate of investment. Here the free boundary provides the optimal time at which the mortgage contract is to be terminated. A number of integral identities are derived and then used to design efficient numerical codes for computing the free boundary. For numerical simulation, parameters for the Vasicek model are estimated via the method of maximum likelihood estimation using 40 years of data from US government bonds. The asymptotic behaviour of the free boundary for the infinite horizon is fully analysed. Interpolating this infinite horizon behaviour and a known near-expiry behaviour, two simple analytical approximation formulas for the optimal exercise boundary are proposed. Numerical evidence shows that the enhanced version of the approximation formula is amazingly accurate; in general, its relative error is less than 1%, for all time before expiry.
Histochemical and Chemical Studies of the Autonomic Innervation of the Ovary

The adrenergic innervation of ovaries of humans, cats and monkeys was studied by a histochemical fluorescence method. Catecholamine-containing nerves were observed in close proximity to blood vessels and within the stromal fibromuscular tissue. The cat ovary contained a dense number of adrenergic nerves. A moderate innervation was seen in the human and fewer nerves in the monkey. Chemical determinations of norepinephrine in the ovaries were consistent with the histochemical observations of the density of catecholamine-containing nerve fibers. Cholinergic nerves were studied by a histochemical method for acetylcholinesterase. Comparatively fewer cholinergic nerves were observed in the ovaries. It is suggested that the adrenergic innervation to the ovary has an influence on ovulation. (Endocrinology 81: 1132, 1967)
Hope and skepticism: Farmer and local community views on the socio-economic benefits of agricultural bioenergy

U.S. government policies and programs promoting agricultural bioenergy development have tended to prioritize national goals of energy security, economic growth and environmental improvement, while marginalizing the local experiences, views and concerns of farmers and rural communities that will produce the needed energy crops. Based on qualitative field interviews with 48 farming and non-farming participants in two switchgrass bioenergy projects (in southern Iowa and in northeastern Kentucky), this paper examines local perspectives on the potential opportunities, drawbacks, and tradeoffs of the emerging agricultural bioeconomy for rural people and places. Individual project participants expressed both positive and negative perceptions about the impacts of the agricultural bioeconomy, with local and regional revitalization being the benefit most desired and also least expected. Skepticism about the social impacts of the agricultural bioeconomy often stemmed from observations of corporate control in agriculture more generally. This research suggests that narrow instrumental views of farmers and rural communities as technical providers of energy feedstocks can be misleading, because they omit the local social and cultural context that complicates rural responses and receptivity to the development of the agricultural bioeconomy.
Calculation of geometric moments using Fourier plane intensities.

A new system for calculating the geometric moments of an input image is presented. The system is based on a mathematical derivation that relates the geometric moments of the input image to the intensity of the Fourier transform of the image. Since optical systems are very efficient at obtaining Fourier transforms, an optical system is used to provide the transform of the input image in this design. An array of detectors is then used to sample the Fourier plane, and a digital postprocessor performs a differentiation process on these Fourier magnitude samples to obtain a vector of values which are combined in a predetermined fashion to provide the geometric moments of the original input function.
Factor analysis of ICD-10 symptom items in the 1988 National Health Interview Survey on Alcohol Dependence.

The present paper analyzes data from the 1988 National Health Interview Survey (NHIS88) of US adults. This general population survey is important in that it is the largest survey to date that collects detailed information on alcohol consumption and alcohol problems. The NHIS88 is a multi-stage complex sample household study with a sample size of about 44 000 adults of which about 20 000 reported that they were current drinkers. Symptom items were used for classification of individuals into categories of alcohol abuse and alcohol dependence based on the DSM-III-R, DSM-IV, and ICD-10 classification. The present analyses are based on 20 items corresponding to the ICD-10 classification, the elements of which are closely related to the Edwards–Gross alcohol dependence syndrome concepts. A single dimension corresponding to alcohol problems in general accounted for much of the correlations among these items, but additional dimensions of interest were also identified. Of the ICD-10 elements only Impaired Control, Tolerance, and Withdrawal could be identified as separate dimensions.
Production, Quality and Hatchability of Eggs from Hens Fed Monensin

Abstract White Leghorn hens were fed a diet containing 0, 50, 100, or 200 p.p.m. of the anticoccidial drug monensin. A level of 200 p.p.m. reduced feed consumption, egg production, and egg weight, compared with birds receiving unmedicated feed. Weight loss was seen in hens receiving 100 and 200 p.p.m. monensin. Feed consumption decreased during the first week while the decrease in egg production was delayed until one week later. Levels of 50 and 100 p.p.m. monensin had no effect on egg production or feed consumption compared with unmedicated controls. No detectable effect was seen with any level of medication on Haugh units, egg shell thickness, or visible quality of eggs. A level of 100 p.p.m. monensin did not affect fertility and hatchability of eggs.
Host Metabolism Regulates Intracellular Growth of Trypanosoma cruzi

Metabolic coupling of intracellular pathogens with host cells is essential for successful colonization of the host. Establishment of intracellular infection by the protozoan Trypanosoma cruzi leads to the development of human Chagas' disease, yet the functional contributions of the host cell toward the infection process remain poorly characterized. Here, a genome-scale functional screen identified interconnected metabolic networks centered around host energy production, nucleotide metabolism, pteridine biosynthesis, and fatty acid oxidation as key processes that fuel intracellular T. cruzi growth. Additionally, the host kinase Akt, which plays essential roles in various cellular processes, was critical for parasite replication. Targeted perturbations in these host metabolic pathways or Akt-dependent signaling pathways modulated the parasite's replicative capacity, highlighting the adaptability of this intracellular pathogen to changing conditions in the host. These findings identify key cellular process regulating intracellular T. cruzi growth and illuminate the potential to leverage host pathways to limit T. cruzi infection.
An evaluation of the pendulum distalizingappliance

Abstract Interest in nonextraction therapy has accelerated the use and development of several molar distalizing appliances requiring minimal patient compliance. The Pendulum appliance, developed by Hilgers, has become one of the more popular designs. This study attempts to evaluate the performance of the Pendulum appliance in correcting Class II malocclusions via molar distalization. Seven patients were treated using this appliance. Lateral cephalographs were taken before treatment and immediately after removal of the appliance. Measurements were taken to evaluate molar movement and changes in angulation. Anchorage loss was measured by evaluating mesial incisor movement and angular changes. Changes in vertical dimension were also noted. Distalization occurred quite rapidly with overcorrection beyond a Class I molar relationship completed in an average time of 3.4 months. Mean distal movement of the upper first molars was 5.1 mm. This movement was accompanied by a mean change in angulation of 15.7°. Anchorage loss was evident with a mean increase in incisor angulation of 4.9° and an average advancement atthe incisal edge of 3.7 mm. Vertical dimension was virtually unaffected. This appliance was an effective means of distalizing molars into a Class I relationship with little patient cooperation. Some side effects were evident such as anchorage loss in the form of increased overjet and molar tipping. These side effects must be taken into account for when considering the use of this appliance.
Empowered Employees as Social Deviants: The Role of Abusive Supervision

The purpose of this study was to examine the effects of psychological empowerment on the relationship between perceptions of abusive supervision and interpersonal deviance. Data were obtained from members of a professional hotel management association (Sample 1: n = 96) and a diverse group of full-time employees (Sample 2: n = 130). We used hierarchical moderated multiple regression analyses to examine the effects of the perceived supervisory abuse × psychological empowerment interaction on coworker- and supervisor-directed deviance. Findings across two samples demonstrated that highly empowered employees were more likely than their less empowered counterparts to engage in coworker-directed deviance when they perceived supervisory abuse, but that psychological empowerment did not moderate the relationship between perceptions of abusive supervision and supervisor-directed deviance. Traditionally, psychological empowerment has been associated with auspicious workplace outcomes (e.g., heightened performance). Results across two samples suggest that highly empowered individuals are more likely than their less empowered counterparts to respond to perceived supervisory mistreatment with coworker-directed deviance. Thus, our results imply that there exists a “dark side” of empowerment such that the negative effects of perceived supervisory abuse trickle over to innocent bystander coworkers, and this relationship is even stronger for empowered employees. This is one of only a few studies to examine moderators capable of altering the negative effects of perceptions of abusive supervision on individuals’ behaviors in the workplace. Additionally, this study is unique given the introduction of psychological empowerment to the abusive supervision literature.
Children and Poverty: Issues in Contemporary Research

The state-of-the-art research in this volume is based on complex, multidimensional conceptions of poverty. Current research goes beyond description to emphasize analysis of processes by which effects occur and variations in effects associated with race, gender, and ethnicity. Child care, school, neighborhood, and community are studied as well as family contexts. The child outcomes investigated include both intellectual development and socioemotional functioning. It is multidisciplinary, using a broad range of analytic frameworks and research methods from economics, sociology, health, psychology, and other disciplines. In this introduction, the overall research trends are described, and new questions for future research are identified.
Stability of Aspirin in Liquid and Semisolid Bases V: Polyglycerol Esters

The stability of aspirin in decaglycerol tetraoleate, decaglycerol octaoleate, and decaglycerol decaoleate was studied at 4, 26, and 45°. Degradation of aspirin in these polyglycerol esters was temperature dependent. Aspirin demonstrated the greatest stability in decaglycerol octaoleate and the lowest stability in decaglycerol tetraoleate at all temperatures studied. The hydroxyl value and the viscosity of the polyglycerol ester appeared to influence the stability of aspirin.
Quenched-in centers in silicon p + n junctions

Abstract Silicon p+n junctions heat treated at high temperatures (1200°C) for a long time (2–20 hr) and then quenched to room temperatures or below shows two deep donor levels (EC−264meV andEC−542meV) in the n-type side of the junction depletion layer which appear to originate from the same imperfection center. The concentration of these levels ranges from 1013 to 1014 cm−3. The junction leakage current comes from carrier generation at the deeper level in the depletion region. Phosphorus gettering was found ineffective in reducing the concentration of these quenched-in levels, but they are annealed out by very slow cooling (25°C/hr to 650°C then quench to room temperatures). The thermal emission and capture rates of electrons and holes at these levels are measured as a function of temperature and electric field by the junction high frequency capacitance and d.c. leakage current transient techniques. It is demonstrated that the detailed balance relationship does not hold. The origin of this double donor center is yet to be identified.
Simulations of Xe@C60 collisions with graphitic films

Collisions between Xe@C60 and sheets of graphite of various dimensions were simulated. A Tersoff many-body potential modeled the interactions between carbon atoms and a Lennard-Jones potential simulated the xenon-carbon interactions. The simulations were compared to experiment and with simulations which implemented other potentials. The results indicate that a relatively small graphite film can be an accurate approximation for a nearly infinite sheet of graphite. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008
Abortion, boxing and zionism: Politics and the APA

Abstract Political resolutions of the American Psychological Association (APA) are critically examined. A sampling of the political resolutions of the APA is provided. Two major issues are addressed: (1) under what conditions it is proper for the APA to make political resolutions; and (2) whether the process by which these resolutions are made is just and reasonable. Finally, we offer suggestions for a more tempered approach that emphasizes the explicit role of scientific data conditions it is proper for the APA to make political resolutions; and (2) whether the process by which these resolutions are made is just and reasonable. Finally, we offer suggestions for a more tempered approach that emphasizes the explicit role of scientific data.
Hot-wire deposition of amorphous and microcrystalline silicon using different gas excitations by a coiled filament

Abstract Microcrystalline silicon (μc-Si:H) and amorphous silicon (a-Si:H) films were deposited using a hot-wire CVD (HWCVD) system that employs a coiled filament. Process gasses, H2 and Si2H6, could be directed into the deposition chamber via different gas inlets, either through a coiled filament for efficient dissociation or into the chamber away from the filament, but near the substrates. We found that at low deposition pressure (e.g. 20 mTorr) the structure of the films depends on the way gases are introduced into the hot-wire chamber. However, at higher pressure (e.g. 50 mTorr), Raman measurement shows similar results for films deposited with different gas inlets.
A note on confidence intervals for the power of t-test

Abstract Tarasinska [2005. Confidence intervals for the power of student's t -test, Statist. Probab. Lett. 73, 125–130] proposes a minimum length method for determining confidence interval estimates for the power of the one-sided t -test at fixed alternative means. This note points out the lack of proof for the coverage probability and provides results to indicate that the nominal coverage probability is not achieved.
Caveat eptor: A comparative study of secure device pairing methods

“Secure Device Pairing” is the process of bootstrapping a secure channel between two previously unassociated devices over a (usually wireless) human-imperceptible communication channel. Lack of prior security context and common trust infrastructure open the door for Man-in-the-Middle (also known as Evil Twin) attacks. Mitigation of these attacks requires user involvement in the device pairing process. Prior research yielded a number of interesting methods utilizing various auxiliary human-perceptible channels, e.g., visual, acoustic or tactile. These methods engage the user in authenticating information exchanged over human-imperceptible channels, thus mitigating MiTM attacks and forming the basis for secure pairing. We present the first comprehensive comparative evaluation of notable secure device pairing methods. Our results identify methods best-suited for a given combination of devices and human abilities. This work is both important and timely, since it sheds light on usability in one of the very few settings where a wide range of users (not just specialists) are confronted with security techniques.