cssi/SciSciGPT-SciSciNet huggingface dataset:
Strain and Surface Energy Effects in Ceramic Processes

Strain and surface energy effects often play important roles in determining both the kinetic nature of phase transformations and in the appearance of metastable high temperature phases. Familiar examples are to be found in the effect of these parameters on the kinetics of the monoclinic-tetragonal transformation in zirconia, the occurrence of high temperature tetragonal ZrO2 as a metastable state at low temperatures, and in the appearance of high cristobalite in samples of opal at room temperature. High surface area powders possessing “excess” surface energy (relative to a large single crystal) are called “active” and exhibit sometimes unusual properties.
The formation of annealing twins

Although annealing twins ore prominent only in recrystallized metals, deformation is not necessary to produce them. Rather, annealing twins may form whenever a grain boundary migrates. The broad annealing twins found in coarse-grained metals are all formed after recrystallization is complete.
Protein phosphatase 2A promotes DNA double-strand break repair through a non-homologous end joining pathway

845 PP2A functions as a potent tumor suppressor but the mechanism(s) remain enigmatic. Here we discovered that PP2A promotes DNA double-strand break (DSB) repair by up-regulating Ku DNA binding and DNA-PK activities. Specific disruption of PP2A activity by either expression of SV40 small tumor antigen or depletion of endogenous PP2A/C by RNA interference results in decreased Ku DNA binding and DNA-PK activities, which leads to suppression of DSB repair and increased genetic instability ( i.e . chromosomal and chromatid breaks). In contrast, overexpression of the PP2A catalytic subunit (PP2A/C) enhances Ku and DNA-PK activities in association with accelerated DSB repair. PP2A co-localizes and interacts with Ku 70 and Ku 86. PP2A directly dephosphorylates Ku as well as DNA-PKcs in vitro and in vivo , which promotes the formation of a functional Ku/DNA-PKcs complex. Intriguingly, PP2A promotes DSB repair in wild type MEF cells but has no such effect in Ku deficient MEF cells, suggesting that Ku 70/86 heterodimer is required for PP2A’s effect on DSB repair. Thus, PP2A promotion of DSB repair may occur in a novel mechanism by activating the non-homologous end-joining pathway, which may contribute to maintenance of genetic stability .
Atraumatic Acute Neck and Back Pain

Case 1: A 39-year-old male with a history of intravenous drug use (IVDU) presents to the ED with a complaint of low back pain. On two prior visits, he was thought to have an etiology of musculoskeletal pain and was discharged after symptomatic treatment. He now complains of numbness in his groin, difficulty urinating, and weakness in his legs. He denies fever or trauma. MRI of his lumbar spine shows an epidural abscess causing compression of the cauda equina nerve roots. He is taken emergently to the OR for decompression.
Survey regarding the 0.05 blood alcohol concentration limit for driving in the United States.

Background: On May 14, 2013, the National Transportation Safety Board (NTSB) proposed that states lower the blood alcohol concentration (BAC) illegal limit from 0.08 to 0.05 g/dL (also referred to ...
On the Zakai Equation of Filtering with Gaussian Noise

The purpose of this work is to present an analogue of the Zakai type equation in case the noise is a Gaussian process, including fractional Brownian motion (fBm). The problem is of interest in view of the fact that the signal sent through the internet is contaminated by the noise given by fBm ([6]). Recently, a similar filtering problem with fBm noise was considered in [1]. However, the authors considered a non—Markovian signal process. The assumption of the Markov property on the signal is realistic. This also leads to a recursive equation, which is easily tractable, and is widely studied ([11, 5]).
Polyethylene Encapsulation of Depleted Uranium Trioxide

Depleted uranium, in the form of uranium trioxide (UO3) powder, was encapsulated in molten polyethylene forming a stable, dense composite henceforth known as DUPoly (patent pending). Materials were fed by calibrated volumetric feeders to a single screw extruder where they were heated and mixed to form a homogeneous molten extrudate. Oxide loadings as high as 90 weight percent (wt%) UO3 were successfully processed, yielding a maximum product density of 4.2 g/cm3. Performance testing included compressive strength, water immersion, and leach testing. Compressive strengths of samples with 50–90wt% UO3 were nearly constant, with a mean value exceeding 15MPa (2,200psi). Leach rates, which increased as a function of sample waste loading, were less than 1.1% after 11 days at ambient temperature for samples containing 90wt% UO3. Ninety day water immersion tests showed sensitivity to “batch” processed UO3 for samples containing >85 wt% of the oxide. Considering that UO3 should be insoluble in water, these results indicate the probable presence of other, more soluble uranium compounds. Samples containing UO3 produced by a “continuous” process showed no deterioration at up to 90 wt% waste loadings.
ON SPACES OF PIECEWISE POLYNOMIALS WITH BOUNDARY CONDITIONS. I. RECTANGLES

In the past few years there has been considerable interest in spaces of piecewise polynomials defined on partitions of a plane region Ω. While the study of such spaces for general partitions is extremely difficult, considerable progress has been made for special kinds of partitions--see e.g. [1–8, 10–11] and references therein.
Effect of Fiber Volume Fraction in Fiber Reinforcement Compaction in Resin Injection Pultrusion Process

In the resin injection pultrusion process (RIP), the liquid resin is injected into the continuously pulled fibers through the injection slots to cause complete wetout of the fibers. As the resin pe...
Lack of urea transporters, UT-A1 and UT-A3, increases nitric oxide accumulation to dampen medullary sodium reabsorption through ENaC.

Although the role of urea in urine concentration is known, the effect of urea handling by the urea transporters (UTs), UT-A1 and UT-A3, on sodium balance remains elusive. Serum and urinary sodium c...
Novel treatments for relapsed/refractory acute myeloid leukemia with FLT3 mutations

ABSTRACTIntroduction: Mutations in the gene encoding for the FMS-like tyrosine kinase 3 (FLT3) are present in about 30% of adults with AML and are associated with shorter disease-free and overall s...
Aerobic exercise training partially reverses the impairment of Nrf2 activation in older humans.

Abstract Nuclear factor erythroid-2-related factor 2 (Nrf2), is an inducible transcription factor that improves redox balance through stimulating antioxidant gene expression. In older humans the Nrf2 response to a single bout of acute exercise is blunted compared to young indicating impaired redox signaling. The purpose of this randomized controlled trial was to investigate if the signaling impairment could be reversed with exercise training in older men and women, while also comparing to young. Young (18-28y, n = 21) and older (≥60y, n = 19) men and women were randomized to 8-week aerobic exercise training (ET; 3 d/wk, 45 min/d) or a non-exercise control group (CON). Nrf2 nuclear localization, gene expression for NQO1, HO1, and GCLC, and GCLC protein were measured in PBMCs in response to acute exercise trial (AET; 30-min cycling at 70% VO2 peak pre- and post-intervention at 7 timepoints (Pre, +10 m, +30 m, +1 h, +4 h, +8 h, +24 h). Young had greater Nrf2 signaling response compared to older at pre-intervention (p = 0.05), whereas the older had significantly higher basal Nrf2 levels (p = 0.004). ET decreased basal Nrf2 expression compared to CON (p = 0.032) and improved the Nrf2 signaling response in both young and older (p Clinicaltrials.gov id NCT03419988 .
Kunal Parker. (2015). Making Foreigners: Immigration and Citizenship Law in America, 1600-2000

Parker, K. (2015). Making Foreigners: Immigration and Citizenship Law in America, 1600-2000. New York: Cambridge University Press. (xii + 259 pp., ISBN: 978-1-107-69851-2).
Interracial Contact in Virtual Reality: Best Practices:

Interracial interactions are occurring more frequently in virtual reality (VR) environments (e.g., multiplayer games, virtual classrooms, medical appointments). Individuals bring their biases and p...
Trajectory Deformations From Physical Human–Robot Interaction

Robots are finding new applications where physical interaction with a human is necessary, such as manufacturing, healthcare, and social tasks. Accordingly, the field of physical human–robot interaction (pHRI) has leveraged impedance control approaches, which support compliant interactions between human and robot. However, a limitation of traditional impedance control is that—despite provisions for the human to modify the robot's current trajectory—the human cannot affect the robot's future desired trajectory through pHRI. In this paper, we present an algorithm for physically interactive trajectory deformations which, when combined with impedance control, allows the human to modulate both the actual and desired trajectories of the robot. Unlike related works, our method explicitly deforms the future desired trajectory based on forces applied during pHRI, but does not require constant human guidance. We present our approach and verify that this method is compatible with traditional impedance control. Next, we use constrained optimization to derive the deformation shape. Finally, we describe an algorithm for real-time implementation, and perform simulations to test the arbitration parameters. Experimental results demonstrate reduction in the human's effort and improvement in the movement quality when compared to pHRI with impedance control alone.
Disparities between US Hispanic and non-Hispanic women in obesity-related perinatal outcomes: a prospective cohort study.

Background Mortality figures and national health surveillance data have demonstrated that Hispanics have a 24% lower risk of all-cause mortality compared to their non-Hispanic counterparts despite increased rates of obesity and related illnesses. Objective The aim of this study is to evaluate if this paradox exists for obesity-related perinatal outcomes in otherwise low-risk Hispanic women. Materials and methods A prospective cohort study of low-risk women across all BMI classes with a singleton, non-anomalous term pregnancy admitted in active labor or undergoing induction of labor between May 2014 and April 2017. All demographic, obstetric, and neonatal outcomes were recorded, and the body mass index (BMI) closest to delivery was used for analysis. Data including composites of adverse maternal and neonatal outcomes were compared across BMI classes and between individuals of Hispanic and non-Hispanic ethnicity. Women with antenatal complications, prior cesarean delivery, and cesarean for non-reassuring fetal status were excluded. Results Of the 11,369 women who met inclusion criteria, 6303 (55%) were Hispanic. Eight percent of Hispanic women were normal weight (BMI: 18.5-24.9), 34% were overweight (BMI: 25-29.9), and 58% were obese (BMI > 30). Fourteen percent of non-Hispanic women were normal weight, 42% were overweight, and 44% were obese. The majority (65%) of women were multiparous. Rate of induction and birthweight increased across BMI for Hispanic and non-Hispanic groups, however the route of delivery was not significantly different (p = .22, 0.16, respectively). Although the association between BMI and composite perinatal complications did not differ by BMI class and ethnicity, the newborns of non-Hispanic women were more likely to be admitted to the neonatal intensive care unit with increasing maternal weight class ( Conclusion There were no demonstrable differences in composite adverse maternal or neonatal outcomes between Hispanic and non-Hispanic obese women. However, newborns of non-Hispanic obese women were more likely to be transferred to the neonatal intensive care unit with increasing maternal BMI.
Bullwhip effects, disruptions and stabilities in a supply network model

We develop a model of differential equations for a supply network with two suppliers in each level and with state-dependent delivery time delays between every two adjacent levels. With the supply network model, we investigate the bullwhip phenomenon and the stabilities of the equilibrium state of order placements, and further delineate factors which can cause onset of periodic oscillations of the order placement decisions. In particular, the impacts of the disruptions are analyzed when a supplier is dysfunctional. We show that if the supply-demand matrix between every two adjacent levels is a Markov matrix, the supply network is most robust with respect to disruptions. Numerical simulations are given to illustrate Hopf bifurcation and the impacts of disruptions on periodic oscillations in the supply network.
Metallurgical Joining of Immiscible System: Pure Mg and Pure Fe

Understanding the metallurgical joinability of pure Mg and pure Fe and their interfacial microstructure lays the foundation for deciphering the complicated mechanism of joining various magnesium alloys and steels in applications. Pure Mg and pure Fe were successfully joined to form a metallurgical bond for the first time using the friction stir assisted scribe technique. Through detailed characterization, we found that the two immiscible metals are bonded by a critical interfacial oxide layer that spans only ~40 ± 10 nm. We present the first direct experimental evidence of the presence of a Mg/Fe oxide rich interfacial layer using high-resolution electron microscopy and discuss the contribution of oxide formation toward a successful joining mechanism.
Vertical Firm Boundaries: Supplier-Customer Contracts and Vertical Integration

I empirically examine the choice of a firm’s vertical boundaries — specifically, the decision to use supplier-customer contracts instead of either using markets or vertical integration. I examine the determinants of supplier-customer contracts using data on a customer’s contractual purchase obligations with its suppliers. Contracting propensity is positively related to supplier relationship-specific investments (RSI), the supplier’s relative bargaining power, and vertical integration costs, and negatively related to contracting costs, alternative sources of information about the customer, and the percentage of a customer’s input traded on financial markets. Additionally, I examine the choice between vertical integration versus supplier-customer contracts and find that the choice is predicted by the type of RSI. Consistent with theory, RSI measured using tangible (intangible) assets are positively related to integration (contracts). Further, industry-wide RSI shocks are related to subsequent changes in a firm’s contracting and integration activity. My results suggest that market frictions play an important role in shaping supplier-customer contracting activity and firm boundaries.
Pedia BP Program: Addressing Pediatric Blood Pressure Readings Using a Smartphone Application

Pedia BP, a free smartphone application, was developed to improve evidence-based clinical practice by simplifying the process of interpreting a pediatric blood pressure measurement. We implemented this application in 2 international community-based programs in Haiti and the Dominican Republic. During well-child checks of 389 children, nurse practitioner students observed an increase in the number of initial elevated blood pressure readings. With the use of health care informatics technology, like the Pedia BP program, pediatric hypertension may be better interpreted and ultimately managed.
Effects of crustal‐scale mechanical layering on magma chamber failure and magma propagation within the Venusian lithosphere

Understanding the connection between shallow subsurface magmatism and related surface expressions provides first-order insight into the volcanic and tectonic processes that shape a planet's evolution. When assessing the role of flexure, previous investigations assumed homogeneous host rock, but planetary lithospheres typically include crust and mantle material, and the mechanical response of a layered lithosphere subjected to flexure may influence both shallow magma reservoir failure and intrusion propagation. To assess the formation of giant radial dike systems, such as those observed on Venus, we create axisymmetric elastic finite element models of a spherical reservoir centered at the contact between stiff, dense mantle overlain by softer, lighter crust. We analyze magma chamber stability, overpressure at rupture, and resulting intrusion types for three distinct environments: lithostatic, upward flexure, and downward flexure. In the lithostatic case, reservoir failure at the crust-mantle contact favors lateral sill injection. In the flexure cases, we observe that failure location depends upon the crust/lithosphere thickness ratio and, at times, will favor radial dike intrusion. Specifically, upward flexure can promote the formation of giant radiating dike swarms, a scenario consistent with a plume-derived origin. Our results present a mechanical explanation for giant radial dike swarm formation, showing that both the stability of magma chambers on Venus and the type of intrusions that form are influenced by lithospheric layering. Furthermore, where dike swarms occur, our approach provides a powerful new way to constrain local crust/mantle layering characteristics within the lithosphere at the time the swarm was forming.
DNA strand breakage and oxygen tension: effects of β-carotene, α-tocopherol and ascorbic acid

Abstract DNA damage is involved in carcinogenesis, aging and other degenerative diseases. The relationship between DNA strand breakage and β-carotene (0.1–1.6 μ m ) was examined under different O2 tensions and with other antioxidants: α-tocopherol (5–80 μ m ), ascorbic acid (10–160 μ m ) and mixtures of these antioxidants. Supercoiled plasmid DNA pBR322 was incubated with 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH) to induce DNA strand breaks in the presence of antioxidants under 15, 150, and 760 torr of O2 tension. Under 15 torr of O2 tension, β-carotene, α-tocopherol, ascorbic acid and mixtures of these antioxidants provided a dose-dependent protection against AAPH-induced DNA strand breaks. The best protection was achieved in the mixture of antioxidants. Under 150 torr of oxygen tension, the antioxidant effect of β-carotene was diminished at ⩾0.8 μ m . A prooxidant effect was found at 0.8⩾μ m β-carotene, producing more single- and double-strand breaks. α-Tocopherol and ascorbic acid exhibited dose-dependent antioxidant effects at 150 torr of oxygen tension. Under 760 torr of O2 tension, the prooxidant effect of 0.8 μ m β-carotene was significant, causing supercoiled DNA to completely breakdown to circular and linear forms. In addition, 760 torr of O2 tension attenuated the antioxidant effects of α-tocopherol and ascorbic acid. Thus, β-carotene causes concentration-dependent DNA breakdown at high O2 tension. The protection of DNA from the prooxidant effects of β-carotene afforded by α-tocopherol and/or ascorbic acid was limited at high O2 tension.
Interactions Determining the Growth of Chiral Domains in Phospholipid Monolayers: Experimental Results and Comparison with Theory

Results are presented from a quantitative analysis of liquid condensed domain shapes in monolayers of the phospholipid d-α-phosphatidylcholine, dipalmitoyl (dipalmitoylphosphatidylcholine or DPPC). We study the effect on liquid-condensed (LC) domain shape of varying in-plane dipole density by examining monolayers composed of different mixtures of the zwitterionic DPPC and anionic phospholipids at high and low electrolyte concentration. Comparison of our data and calculations with existing theories show that the dominant dependence of the shape factor (a measure of the noncompact geometry of LC domains) on in-plane density is described well by electric dipole−dipole interactions; however, the detailed chiral shapes of the liquid-condensed domains remains unexplained. Also unaccounted for is the noncompact growth of LC domains either at electrolyte concentrations high enough to screen out electric dipole interactions or in mixtures with anionic phospholipids. We have also tested the prediction of linear sta...
Crystal Structure and Mechanism of Tryptophan 2,3-Dioxygenase, a Heme Enzyme Involved in Tryptophan Catabolism and in Quinolinate Biosynthesis†,‡

The structure of tryptophan 2,3-dioxygenase (TDO) from Ralstonia metallidurans was determined at 2.4 A. TDO catalyzes the irreversible oxidation of l-tryptophan to N-formyl kynurenine, which is the initial step in tryptophan catabolism. TDO is a heme-containing enzyme and is highly specific for its substrate l-tryptophan. The structure is a tetramer with a heme cofactor bound at each active site. The monomeric fold, as well as the heme binding site, is similar to that of the large domain of indoleamine 2,3-dioxygenase, an enzyme that catalyzes the same reaction except with a broader substrate tolerance. Modeling of the putative (S)-tryptophan hydroperoxide intermediate into the active site, as well as substrate analogue and mutagenesis studies, are consistent with a Criegee mechanism for the reaction.
Two-year clinical evaluation of light-cured composite resin restorations in primary molars

The clinical performance of an experimental, light-activated composite resin for primary molars is eval­uated and compared with ADA guidelines and a previous study of amalgam restorations in primary molars. Factors such as postoperative sensitivity, anatomic form, and secondary caries are investigated in a…
Synchronously pumped subpicosecond dye oscillator-amplifier system.

A tunable subpicosecond dye oscillator–amplifier system that produces 0.20-mJ, 190-fsec pulses at 620 nm in a nearly diffraction-limited beam is demonstrated. The output pulse is temporally broadened by 10% relative to the input pulse. The system consists of a synchronously pumped subpicosecond dye laser followed by a dye amplifier that is quasi-longitudinally pumped using the frequency-doubled output from a Nd:YAG regenerative amplifier.
Effects of fenfluramine and antidepressants on protein kinase C activity in rat cortical synaptoneurosomes.

Fenfluramine releases serotonin (5-HT) via the 5-HT transporter (SERT). Previous work has shown that amphetamine increases particulate protein kinase C (PKC) activity in striatal synaptoneurosomes. The increased PKC activity is linked to the outward transport of dopamine, and when release is diminished, the inward transport of amphetamine inhibits PKC instead. Since there is homology among monoamine transporters, this study was undertaken to determine if D-fenfluramine has similar effects on PKC. The role of 5-HT receptors and endogenous 5-HT were also examined. Naive rats and rats pretreated with p-chlorophenylalanine (PCPA), a 5-HT synthesis inhibitor, were sacrificed. Cortical synaptoneurosomes were prepared and incubated with fenfluramine. PKC activity was determined by thiophosphorylation of endogenous substrates. It was found that 5-HT, D/L-fenfluramine, and D-fenfluramine increased PKC activity in a time- and dose-dependent manner. The 5-HT-mediated increase in PKC activity was attenuated by pretreatment with the 5-HT(2) antagonist ketanserin, but not with the SERT inhibitor fluoxetine. The D-fenfluramine-induced increase in PKC activity was completely prevented, however, by pretreatment with SERT inhibitors and partially with ketanserin. It was also attenuated by pretreatment with PCPA, resulting in a dose-dependent inhibition of PKC instead. Thus, when 5-HT release was diminished the uptake of D-fenfluramine inhibited PKC. Similar effects have been observed with amphetamine. Unlike D-fenfluramine, the D/L-fenfluramine-induced increase in PKC activity was partially resistant to PCPA pretreatment but was attenuated with bupropion, a dopamine transporter (DAT) inhibitor. SERT inhibitors (sertraline, paroxetine, citalopram, and fluoxetine) also increased PKC activity. Nefazodone and bupropion increased PKC activity, but mirtazapine was relatively inactive. The SERT inhibitor-induced increase in PKC was unaffected by pretreatment with PCPA but was inhibited by calcium. Similar effects on PKC activity have been observed with DAT inhibitors. These results, showing that D-fenfluramine altered PKC activity similar to D-amphetamine, suggest that the topographic homology between DAT and SERT may extend to their effects on PKC activity.
Inadequate pain management and associated morbidity in children at home after tonsillectomy

A telephone interview with the parents of 84 children who underwent tonsillectomy was conducted within 24 hours after discharge from an ambulatory surgery center. Parents were asked to rate the intensity of their child's pain and data were collected on the type, dose, and amount of analgesics administered, and the types of side effects the children experienced. The mean age of the children was 7 years (SD = 2.31), with an equal number of boys and girls. Overall mean pain intensity was 1.42 (SD = 0.71) and the worst pain intensity ranged from 0 to 3 (Mean = 1.93; SD = 0.83). Acetaminophen with codeine was the most common analgesic prescribed and administered. Children received an average of 3 doses in the first 24 hours after surgery. Seventy-seven percent of the parents stated that pain relief from the analgesic was adequate. Of the 23% who did not feel that pain control was adequate, only 7% contacted a physician. The majority of the children experienced restless sleep (62%), behavior changes (75%), and difficulty taking oral fluids because of complaints of pain (56%). Twenty-six percent of the children had one or more episodes of emesis. Our data suggest that children experience a significant amount of pain in the first 24 hours after tonsillectomy and that parents administer analgesics less frequently than the drugs are prescribed. In addition, children experience significant deleterious effects (i.e., poor oral fluid intake, sleep disturbance, behavioral changes, and emesis) associated with the undertreatment of pain, the analgesic administered, or the surgery itself.
Experimentelle Untersuchungen über eine Form von Ruhetremor an den Extremitäten von gesunden Hunden

1. Wahrend verschiedener Arten akuter agonaler Zustande wurden bei Hunden eine Reihe physiologischer Grosen gemessen und registriert und zwar unter besonderer Berucksichtigung des sogenannten „normalen Ruhetremors“ der Extremitaten.
Experimental and numerical study of buoyancy-induced flow and heat transfer in an open annular cavity

Abstract This paper presents experimental and numerical results for natural convection in a horizontal, annular cavity which communicates with the surroundings through its open end. In the experimental study, a known heat flux was applied to each component of the cavity (inner cylinder, inner cylinder tip, outer cylinder and end-wall) and local surface temperature measurements were made to determine heat transfer characteristics of the convective flow. Trends in the experimental data have been explained in terms of the physical mechanisms underlying the buoyancy induced flow. Smoke flow visualization using laser-induced lighting was performed to understand the flow field around the open end of the cavity. The heat transfer results were correlated by Nu av =0.0131(Ra∗) 0.378 for the range of Rayleigh numbers considered ( 1.3 × 10 9 9 ) in the experiments. In the numerical investigation, solutions to the three-dimensional time-averaged (Reynolds') steady-state equations of fluid motion and heat transfer, were obtained using a finite element analysis. Results of the conjugate study including the local temperature distributions, heat transfer coefficients and the flow field showing the interactions between the ambient and cavity flow fields agreed favorably with experimental results. The present work provides, for the first time, validated heat transfer data for high Rayleigh number buoyancy-induced flows in open annular cavities.
Considerations of specimen damage for the transmission electron microscope, conventional versus scanning.

Abstract We have previously shown that the transmission scanning electron microscope is capable of giving a resolving power equal to that of a conventional electron microscope, that it can be used to provide all the same contrast modes, but that it offers the advantage of new forms of contrast and can provide direct numerical outputs (Crewe & Wall, 1970 a , b ; Crewe et al . 1970; Crewe, 1970). One question that we have not previously discussed is that of specimen damage, but in view of the similarity in performance between the two types of machine it has become important to do so. Recent remarks of Scherzer (1971) have been widely misinterpreted as indicating that the scanning microscope causes more specimen damage. However, he has confined his attention to the highest conceivable resolution of 0·4 A, where we agree with his general conclusion (barring advances in scanning microscope technology). As we will demonstrate, the conclusion is not valid for normally attainable resolutions.
Natural waveform translation and scaling in early vision

The wavelet transform dilates and translates a selected fundamental wavelet. Selective sampling of the continuous wavelet transform identifies discrete components used as a basis for signal projections. Similarly, some properties of early vision may be descried in terms of dilations and translations of fundamental waveforms. Examples include the optical point spread function, spectral absorption curves of photoreceptors, receptive fields of photoreceptors. Receptive fields of post-receptor cells, and eye movements. These vision features are described with respect to the dilation and translation of candidate waveforms. Spatial, temporal, and chromatic filtering in the vision pathways are also describe with respect to similarities with wavelet subband analysis.
The element of surprise.

Endocannabinoids are versatile molecules, regulating a variety of functions in the body. Daniele Piomelli explores how recent clinical trials testing rimonabant, an inhibitor of endocannabinoid signaling, for weight loss emerged from studies of individuals with schizophrenia; such trials have spurred basic research into how endocannabinoids affect both energy use and mood. Beat Lutz and Krisztina Monory examine how rimonabant might prove useful for preventing the development of adult epilepsy in response to fever-induced seizures in infants and young children.
The need for flexibility in preparing clinician-scientists for academic careers.

and to recommend action steps that might be appropriate for the Society; (2) that a morning session during each annual meeting be devoted to discussion of a specific topic that concerns academic departments; (3) that the members of the Committee on Graduate Education and of the Program Committee cooperate in selecting the issue to be considered and in developing the program; and (4) that knowledgeable individuals, not necessarily Fellows of the American Gynecological and Obstetrical Society, be invited to prepare position papers to be presented and discussed during the session and that the papers and discussions be considered for publication with the scientific papers. We also recommended that the first such session be developed for the 1985 meeting and that the subject be “Flexibility in obstetric-gynecologic residencies: why is it necessary?” Obviously, the Council approved the suggestion Finally, I should like to thank the members of both Committees who worked so diligently and effectively in gathering information on the issues and for their assistance in preparing the final reports. I also thank Drs. Jaffe and Hendricks for agreeing to prepare and present the papers today and to Drs. Merrill and Pitkin for their responses. They obviously share the concerns of the committee members.
The factored-SVD formulation and an application example

Recent work has shown how the singular value decomposition (SVD) may be used in a multiresolution form analogous to the wavelet decomposition. Here it will be shown how a particular realization of the multiresolution SVD (MR-SVD) yields a decomposition into Kronecker products which enables efficient synthesis of the original signal. Furthermore, it is demonstrated that the resulting decomposition (called the factored-SVD), when applied in similar fashion to a wavelet packet decomposition, provides a significant reduction in distortion over the well-known Karhunen-Loeve transform (KLT) as a result of rate-distortion coding in a higher dimensionality space. Application to the 512x512 Lena image indicates SNR improvements of almost 20 dB, which are in agreement with the theoretical development. Finally, other future applications are suggested.
Effectiveness of commercial household steam cleaning systems in reducing the populations of Listeria monocytogenes and spoilage bacteria on inoculated pork skin surfaces

Abstract In a previous study conducted in our laboratory, a commercial household steam cleaner was found to be effective in reducing the naturally occurring bacterial populations on 72 beef and 72 hog carcasses processed by four small and very small meat processing plants. The goals of this study were to determine the maximum levels of bacterial reduction caused by treatments using the steam cleaner, and to compare the efficacy of this cleaner with the efficacies of two other commercial household steam cleaning systems in reducing bacterial populations on the surface of pork skin artificially inoculated with ca. 7.61 or 5.75 log 10 CFU / cm 2 of Listeria monocytogenes. The contaminated pork skin samples were treated with the three stream cleaners for 30–180 s in 30 s intervals, and assayed for the populations of L. monocytogenes as well as total aerobic and thermoduric bacteria. The application of steam significantly reduced the population of L. monocytogenes (7.61– 3.23 log 10 CFU / cm 2 ), as well as total aerobic (5.68– 4.04 log 10 CFU / cm 2 ) and thermoduric (6.12– 2.57 log 10 CFU / cm 2 ) bacteria on the surface of pork skin ( P ⩽ 0.05 ) . Significant differences in microbial reductions were observed between different inoculation levels, treatment times, and types of cleaning systems used in the study ( P ⩽ 0.05 ) .
Effect of citric acid and lyophilized autologous plasma on healing following periodontal flap surgery in monkeys.

The purpose of this histologic, histometric, and autoradiographic study was to examine the effect of citric acid conditioning and lyophilized autologous plasma (LAP) application on healing following periodontal flap surgery. Mucoperiosteal flaps were elevated in six rhesus monkeys using the modified Widman flap procedure. A total of 24 quadrants were treated, each included the first and second premolar and first and second molar teeth. Cementum was removed from the exposed root surfaces, and reference notches were inscribed into the roots at the alveolar bone margin. Two treatment modalities were employed: ( 1 ) surgery plus citric acid conditioning, to serve as control and (2) surgery plus citric acid followed by LAP application (400 mg/ml saline). Flaps were returned to their preoperative positions and sutured. Animal sacrifices were scheduled to provide observations 3, 7, 14, 21, 28, and 45 days after surgery. Each monkey received an intravenous injection of tritiated thymidine, 1 μCi/gm of body weight...
Principle of equivalency of the phase difference and off-axis tilt sensing technique with a laser guide star

A full aperture tilt sensing technique which does not require transmitting laser irradiance through the main optical train is described. This technique is based on measurements of differential motion of the images of the two laser guide stars (LGSs) formed in the atmospheric sodium layer by the two parallel collimated laser beams separated at a distance equal to the telescope diameter. It is shown that a one-axis wavefront tilt component might be determined by measuring the LGS's differential motions simultaneously with the main telescope and with an auxiliary telescope. To sense two tilt components, four laser beam and two auxiliary telescopes are needed. A tilt angular anisoplanatism is studied, and parameter of the tilt measurement scheme are estimated.
Bulk plasma properties in the pulsed glow discharge

Abstract This work focuses on the spatial and temporal characteristics of a glow discharge plasma operated with power pulses of 5 ms in duration at 25% duty cycle. Interpretation of emission data provides insight into the nature of the plasma at each instant of a typical pulse cycle and at each position in space. Because the bulk plasma properties affect the distribution of excited energy levels of the sputtered atoms, an improved understanding of the plasma affords the ability to select conditions that enhance analytically important emission lines. Optical emission spectroscopy was used to determine the relative populations of excited states for atoms and ions during the initial breakdown, the steady state and the recombining periods of the discharge pulse cycle. The plasma is highly ionizing in nature at the time of breakdown—with lower excited states being overpopulated—before reaching the steady state, or plateau, period, also ionizing in nature. These behaviors arise from a loss of charged particles and photons to the surroundings that shifts the plasma away from Saha and Boltzmann balances during these periods. The post-pulse period typically displays recombining behavior, characterized by population inversion for selected species—except for regions close to the cathode, where electrons and ions are lost by diffusion and are not available for recombination. The sputtered analyte atom emissions closely mimic those of the plasma bath gas, except that their emissions persevere for longer in the recombining after-peak period than do the discharge gas species.
Production, in Venezuela, of indigenous varieties of tobacco

These varieties, still cultivated in a primitive manner, may have value for hybridizing with Burley and Virginia tobaccos. In Venezuela the leaves are manufactured into cigars or are extracted to produce the masticatories known as “chimo” and “tobacco rope”.
Aggression as a component of relative fitness in four inbred strains of mice.

In four separate experiments, male mice from the RF/J, BALB/cJ. DBA/2J, and C57BL/6J strains were grouped in a seminaturalistic environment with females from the C57BL/6J strain. Observations were made concerning the aggressive behavior of the different strains, and starch gel electrophoresis of the esterase III and hemoglobin proteins was used to determine paternity of the offspring. Results indicated that the most aggressive strain, RF/J, sired 95.6% of all offspring. Control groups indicated that the reproductive disadvantage of the BALB and C57 males could be explained in terms of differences in general fertilizing ability, the effects of grouping mice together, or pregnancy blockage. These factors alone were not sufficient to explain the disadvantage of the DBA males. Differences in fighting success may therefore be an important determinant of fitness differences between RF and DBA males.
The Hidden Perils of Career Concerns in R&D Organizations

This research examines how certain economic incentives can lead agents to prefer difficult solutions to their organizational tasks that reduce their likelihood of obtaining a successful task outcome. Drawing on the career concerns literature, I model a decision context in which agents have the operational autonomy to choose among different solutions. Analyzing this model reveals that agents with career concerns will, under certain conditions, deliberately reduce their likelihood of succeeding with a task by choosing a solution that makes their task more difficult. These findings suggest that highly capable agents prefer moderately difficult tasks to showcase their capability, while less-capable agents prefer highly difficult tasks to mask their lack of capability. The robustness of these results is examined in various extensions. Furthermore, the paper provides insights on how incentives can be designed to alleviate this problem.
Now on display: a gallery of group II intron structures at different stages of catalysis

Group II introns are mobile genetic elements that self-splice and retrotranspose into DNA and RNA. They are considered evolutionary ancestors of the spliceosome, the ribonucleoprotein complex essential for pre-mRNA processing in higher eukaryotes. Over a 20-year period, group II introns have been characterized first genetically, then biochemically, and finally by means of X-ray crystallography. To date, 17 crystal structures of a group II intron are available, representing five different stages of the splicing cycle. This review provides a framework for classifying and understanding these new structures in the context of the splicing cycle. Structural and functional implications for the spliceosome are also discussed.
Conditions affecting the extracellular space in the frog's forebrain.

The forebrain of the isolated central nervous system of frogs was fixed by freeze substitution and studied with the electron microscope. The extracellular space (ECS) of brains kept for 15–20 min in a physiological salt solution at room temperature varied from an appreciable to a negligible one. In electron micrographs exhibiting a large ECS the tissue elements had a uniform electron density. The EMs with little space featured in some instances a moderate swelling of presynaptic terminals and other tissue elements. Brains kept in a cooled medium or a salt solution with MgCl2 added exhibited invariably an abundant ECS. Treating the brain with a 100 mM KCl solution 5–90 sec before freezing yielded EMs with a contracted ECS and swollen tissue elements, many of which could be identified as dendritic spines. This effect of KCl was in many experiments prevented by bathing the brain in a salt solution containing 10 mM MgCl2 or in a Ca-free solution.
A DEA study of gender equity in executive compensation

This study assesses whether annual and long-term compensation for senior executive women is equal to annual and long-term compensation for senior executive men. The group of executive women includes those women reported in the compensation tables of proxy statements for the companies in the Standard and Poors (S&P) 500 for 1997. Their compensation was compared to the compensation for two samples of executive men from S&P 500 firms using data envelopment analysis. The results indicate that the compensation paid to executive women is equitable to the compensation paid to executive men.
Hydrogen-Storage Properties of Nanocrystalline Mg-Based Materials Created through Controlled Devitrification of a Metallic Glass

Mg-based nanostructured materials with a composition of Mg85Ni15-xMx (M=Y, La, or Pd) have been fabricated by proper alloying additions and controlling the crystallization process of melt spun metallic glass ribbon. XRD suggests that the average crystallite sizes range from 100 nm in the binary materials to <30 nm in the ternary alloys. Hydrogen absorption/desorption measurements show improved properties compared to nanocrystalline alloys fabricated using other processing strategies. Surface treatment of the binary and Pd-containing ribbons by ball milling or submersion in aqueous NH4+ allows the materials to be activated at 473 K, significantly lower than conventional Mg-based hydrogen storage materials. Y and La additions improve the maximum storage capacity. Absorption kinetics are also improved the materials is alloyed with La, while Y slows the reaction kinetics. Some degradation in storage capacity is observed when the materials are exposed to a cyclic absorption/desorption process, likely due to microstructural coarsening. The Mg85Ni10Pd5 composition fully absorbs and desorbs ≈5 wt. % H at 473 K, while other bulk Mg-based materials require temperatures in excess of 573 K.
Age differences in the control of postural stability during reaching tasks

Reaching tasks are commonly performed during daily activities and require anticipatory postural adjustments (APAs) to ensure a stable posture during movement execution. Age-related changes in APAs may impact dynamic balance and cause postural instability during reaching tasks made from standing. The present study examined age differences in postural control during reaching to targets located at different heights. Fourteen young adults (aged 20.0±1.5 yrs) and 16 community-dwelling older adults (aged 73.4±5.3 yrs) participated in the study. The task involved reaching forward to grasp a cylinder, and returning to an upright position as fast and accurately as possible. Postural control was analyzed using the center of pressure (COP) during four phases of the task: COP displacement during APA production, COP trajectory smoothness during the reach and return phases, and COP path length during the recovery phase following movement. APA amplitude measured by COP displacement and COP path length during the recovery phase was larger in older compared to young adults. Dynamic balance represented by COP trajectory smoothness was reduced with age. In both age groups, APA amplitude was largest and COP trajectory smoothness the least during low target reaches. The results demonstrate that, while older adults can alter APAs in order to maintain postural stability, control of COP during movement execution, particularly during low target reaches, is compromised with aging. These findings have clinical implications for both the assessment of dynamic balance and the development of balance training programs.
New and emerging therapies for pulmonary complications of cystic fibrosis.

In the decade since the gene for cystic fibrosis (CF) was discovered, research into potential therapeutic interventions has progressed on a number of different fronts. The vast majority of morbidity and mortality in CF results from inflammation and infection of the airways. Direct delivery of antibacterials to the airway secretions via a nebuliser is an attractive therapeutic option, and a novel formulation of tobramycin designed for such a purpose has been demonstrated to improve spirometry and decrease the need for intravenous antibacterials. In addition, early clinical trials are studying the effects of small peptides with antibiotic properties (defensins) delivered directly to the airways.
Use of Normalized Difference Water Index for monitoring live fuel moisture

Normalized Difference Vegetation Index (NDVI) and Normalized Difference Water Index (NDWI) were compared for monitoring live fuel moisture in a shrubland ecosystem. Both indices were calculated from 500 m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data covering a 33‐month period from 2000 to 2002. Both NDVI and NDWI were positively correlated with live fuel moisture measured by the Los Angeles County Fire Department (LACFD). NDVI had R 2 values ranging between 0.25 to 0.60, while NDWI had significantly higher R 2 values, varying between 0.39 and 0.80. Water absorption measures, such as NDWI, may prove more appropriate for monitoring live fuel moisture than measures of chlorophyll absorption such as NDVI.
Multilayer relaxation of clean Ag{001}

Analyse de l'intensite de diffraction des electrons lents a partir d'une surface propre d'Ag {001}. On ne trouve aucune relaxation multicouche. Comparaison avec d'autres resultats de surfaces cfc {001}