cssi/SciSciGPT-SciSciNet huggingface dataset:
Implosive, eclectic verbal and bibliotherapy in the treatment of fears of snakes.

Abstract Thirty co-eds with ascertained fears of snakes were exposed to an implosive, eclectic verbal or bibliotherapy session. Ten Ss were in each group. For a S to be judged a success at the conclusion of the session, she had to pick up a 3 1 2 ft king snake. There were significant differences (0.05 level) between Ss who had implosive therapy and those who had bibliotherapy on the post test. No significant differences were found between the implosive and eclectic verbal Ss on this post test. Subjects who failed to pick up the snake were subsequently imploded. 66.66 Per cent of them later lifted up the animal. Results of this study were compared with those of previous research on implosion.
Human Brain β-Hydroxybutyrate and Lactate Increase in Fasting-Induced Ketosis:

Ketones are known to constitute an important fraction of fuel for consumption by the brain, with brain ketone content generally thought to be low. However, the recent observation of 1-mmol/L levels of brain beta-hydroxybutyrate (BHB) in children on the ketogenic diet suggests otherwise. The authors report the measurement of brain BHB and lactate in the occipital lobe of healthy adults using high field (4-T) magnetic resonance spectroscopy, measured in the nonfasted state and after 2- and 3-day fasting-induced ketosis. A 9-mL voxel located in the calcarine fissure was studied, detecting the BHB and lactate upfield resonances using a 1H homonuclear editing sequence. Plasma BHB levels also were measured. The mean brain BHB concentration increased from a nonfasted level of 0.05 +/- 0.05 to 0.60 +/- 0.26 mmol/L (after second day of fasting), increasing further to 0.98 +/- 0.16 mmol/L (after the third day of fasting). The mean nonfasted brain lactate was 0.69 +/- 0.17 mmol/L, increasing to 1.47 +/- 0.22 mmol/L after the third day. The plasma and brain BHB levels correlated well (r = 0.86) with a brain-plasma slope of 0.26. These data show that brain BHB rises significantly with 2- and 3-day fasting-induced ketosis. The lactate increase likely results from ketones displacing lactate oxidation without altering glucose phosphorylation and glycolysis.
Responsibility of the dentist in complete dentures

Abstract The dentist is obligated to perform certain essential phases of complete denture construction. These include making a comprehensive diagnosis, making certain that the oral tissues are healthy before work is started, making the impressions, producing jaw relation records, selecting the teeth, correcting the jaw relation records, rearranging the anterior teeth for esthetic appearance, correcting the occlusion at the time of the first insertion of the dentures, and making whatever denture adjustments may be necessary. If the dental profession is to maintain its high standard of denture service, the dentist must not delegate to someone else any phase of denture construction he should complete himself.
Foot drop as a harbinger of aortic occlusion.

A man presented with foot drop and 2 months later an infrarenal occlusion of his abdominal aorta was discovered. Initial evaluation found no structural etiology for his nerve injury. His neurologic deficits progressed until gangrenous changes developed in his feet leading to the discovery of aortic occlusion. This case demonstrates that peripheral nerve injury in the legs may signal underlying large vessel occlusive disease. We discuss the localization and potential mechanisms of ischemic nerve injury. © 1995 John Wiley & Sons, Inc.
Knudsen aerosol evaporation

Abstract The evaporation kinetics of submicron aerosol droplets has been studied by measuring the size of single droplets as a function of time using laser light scattering from the droplet. By suspending a charged droplet in an electric field in a light scattering cell, precise measurements of droplet size have been made over a range of total pressures corresponding to diffusion-controlled evaporation and Knudsen aerosol evaporation. The results are compared with available theoretical and semitheoretical predictions for Knudsen aerosol transport processes. For the systems studied, dioctyl phthalate in helium and in nitrogen, the results are consistent with an evaporation coefficient of unity. Furthermore, the technique can be used to determine diffusion coefficients and vapor pressures for relatively nonvolatile species.
Coupling between Large-Scale Atmospheric Processes and Mesoscale Land–Atmosphere Interactions in the U.S. Southern Great Plains during Summer. Part I: Case Studies

Abstract This paper is Part I of a two-part study that uses high-resolution Regional Atmospheric Modeling System (RAMS) simulations to investigate mesoscale land–atmosphere interactions in the summertime U.S. Southern Great Plains. The focus is on the atmospheric dynamics associated with mesoscale heterogeneity in the underlying surface fluxes: how shifts in meteorological regimes modulate these diurnal, mesoscale processes, and their overall impact at larger scales and over multiple diurnal cycles. Part I examines individual case study time periods drawn from the simulations that illustrate general points about the key land–atmosphere interactions. The main findings are as follows: The mesoscale processes are embedded within a synoptic-scale organization that controls the background meteorological regime at a given location. During the clear, dry days in the simulated months, heterogeneity in the surface fluxes forces strong, lower-tropospheric, mesoscale circulations that exhibit a characteristic dynami...
Carbon–heteroatom bond formation catalysed by organometallic complexes

At one time the synthetic chemist's last resort, reactions catalysed by transition metals are now the preferred method for synthesizing many types of organic molecule. A recent success in this type of catalysis is the discovery of reactions that form bonds between carbon and heteroatoms (such as nitrogen, oxygen, sulphur, silicon and boron) via complexes of transition metals with amides, alkoxides, thiolates, silyl groups or boryl groups. The development of these catalytic processes has been supported by the discovery of new elementary reactions that occur at metal-heteroatom bonds and by the identification of factors that control these reactions. Together, these findings have led to new synthetic processes that are in daily use and have formed a foundation for the development of processes that are likely to be central to synthetic chemistry in the future.
Reinnervation of stratum lucidum by hippocampal mossy fibers is developmentally regulated

Mossy fibers from dentate gyrus granule cells establish synapses on CA3 pyramidal neurons during the first 3 postnatal weeks in the rat. Mossy fiber synapses are primarily restricted to the stratum lucidum. When examined by Timm stain after 10-14 days in vitro, cultured hippocampal slices from postnatal day 4 rat pups show a similar mossy fiber termination pattern in stratum lucidum. Thus, axon guidance cues used by mossy fibers in vivo appear to be preserved in these cultured slices. Three experimental manipulations were performed on hippocampal slice cultures to examine whether the axon guidance cues used by mossy fibers are developmentally regulated. First, mossy fibers were transected on the day of culture or day 7 in vitro. Mossy fibers transected on either day were able to reestablish their synaptic pattern in stratum lucidum of CA3. Second, dentates and hippocampi of same age or different age were co-cultured. Same age co-cultures (P4 dentates to P4 hippocampi or P11 dentates to P11 hippocampi) showed good mossy fiber reinnervation of stratum lucidum, as did different age co-cultures from P4 dentates to P11 hippocampi. However, P11 dentates to P4 hippocampi co-cultures showed little mossy fiber reinnervation of stratum lucidum. Third, new P4 or P11 dentates were co-cultured onto hippocampal slices in which mossy fibers had been allowed to degenerate. New mossy fibers reinnervated these hippocampi, but did not reestablish their normal synaptic pattern in stratum lucidum. These three experimental manipulations suggest that mossy fiber axon guidance mechanisms are developmentally regulated, and that existing mossy fibers play a role in directing mossy fiber reinnervation of stratum lucidum.
Covariance and the Feynman Rules of a Massive Gauge Theory

If the interaction Lagrangian contains derivatives, or if the spins of the interacting particles \ensuremath{\ge} 1, then both the propagators and the interaction Hamiltonian contain normal-dependent terms. Lee and Yang showed that if the noncovariant part of the propagator is dropped, then the finite interaction Hamiltonian is modified. In addition, there appears a term that is divergent, anti-Hermitian, and generally noncovariant if it does not vanish, namely, $\ensuremath{\delta}H=\frac{1}{2}i\ensuremath{\hbar}{\ensuremath{\delta}}^{4}(0)\ifmmode\times\else\texttimes\fi{}\mathrm{ln}\mathrm{det}g$, where $g$ depends on the structure of the theory. For massive gauge theories we have shown that $\ensuremath{\delta}H=0$ and that ${H}_{\mathrm{int}}=\ensuremath{-}{L}_{\mathrm{int}}$. These theories are manifestly covariant and the ordinary Feynman rules hold. Renormalization is not discussed.
Print-quality enhancement in electrophotographic printers

Print-quality enhancement (PQE) is a sophisticated form of image enhancement that is used to improve print quality. The benefits of PQE include reduced edge raggedness, control over boldness, stroke-imbalance correction, and improvements to the appearance of patterns that are difficult to print. Use of PQE permits one to obtain high-quality printing while using printers with lower resolution than would be required otherwise. Data bandwidth and storage requirements are therefore reduced. PQE relies on an imaging system with multiple exposure levels. A PQE algorithm generates an exposure value for each picture element (pel) based on neighboring bilevel pels. Since the exposure value is generated algorithmically, there is no need to store or internally transmit multiple bits per pel. This paper describes the capabilities of PQE and illustrates the level of print-quality improvements that can be obtained. Imaging-system requirements are presented, with attention to the modulator technology. The major focus is a PQE model that includes the PQE algorithm from the bitmap algorithm through the image-writing process.
Influence of Ozone Stress on Soybean Response to Carbon Dioxide Enrichment: I. Foliar Properties

Tropospheric O₃ can cause foliar injury, decreased growth, and decreased yield, whereas CO₂ enrichment generally causes opposite effects. Little is known about plant response to mixtures of O₃ and CO₂. Open-top field chambers were used to determine if foliar responses of soybean [Glycine max (L.) Merr.] to CO₂ enrichment are affected by O₃ stress and vice versa. Plants were grown in 14-L pots and exposed to four CO₂ and three O₃ concentrations in 12 combinations. The CO₂ treatments were ambient (366 μL⁻) and three treatments with CO₂ added for 24 h d 1 at approximately 1.3, 1.6, and 2.0 times ambient. The O₃ treatments were charcoal-filtered air (CF), nonfiltered air (NF), and NF with O₃ added for 12 h⁻¹ (NF+), resulting in seasonal concentrations of approximately 20, 46, and 75 μL L⁻¹. Foliar effects of CO₂ enrichment were dependent on the amount of stress caused by O₃. In the CF treatment, plants were not stressed by O₃, and CO₂ enrichment caused chlorosis and decreased chlorophyll. In the NF and NF+ treatments, plants were stressed by 03, and CO₂ enrichment suppressed chlorosis and increased chlorophyll. Ozone decreased specific leaf weight, increased foliar N and C, and decreased C/N ratios, whereas CO₂ caused opposite responses for these measures. Ozone increased foliar S and B but did not affect P or K concentrations. Conversely, CO₂ enrichment suppressed foliar S, B, P, and K concentrations. These interactions between O₃ and CO₂ emphasize a need to consider the amount of plant stress caused by O₃ in studies to measure effects of CO₂ enrichment. Cooperative investigations of the USDA-ARS Air Quality Research Unit and the North Carolina State University. Funded in part by the North Carolina Agricultural Research Service.
Development of a New HVAC Flow System for the Next Generation Automated People Mover

IHI has succeeded in development of a new generation Automated People Mover (APM). One of the features of this APM is the composite car body which enables stylish exterior, spacious cabin and light weight. This feature demanded the development of a new Heating, Ventilating, and Air-Conditioning (HVAC) system, which does not have any devices on the roof of the car, to avoid heavy weight on the composite body and to keep the cabin ceiling high for passenger comfort. Consequently we adopted a new HVAC flow system in which the air is supplied upwards from the bottom of the side windows while all the mechanical devices are placed under the floor. However, when the prototype was first designed, it caused congested flow channel due to its location and we had to have ducts that were too small. It was unexpectedly difficult to keep the space for HVAC system like in an ordinary layout. So at first, the prototype vehicle did not have enough HVAC performance due to lack of air flow. Therefore we performed full review of the duct system. We made desk analysis, duct model test, experiment on the prototype, and CFD simulation, for the improvement of the new HVAC flow system. Finally, we have established an excellent system with the new layout which has been validated on the prototype vehicle. In this paper, we describe the process of developing a new HVAC system, based on the results of actual measurement as well as CFD simulation.Copyright © 2011 by JSME
Root Growth Effects on Soluble C and P in Manured and Non-manured Soils

There is limited research on relationships between root characteristics and soil chemical properties and processes. Because previous studies have shown specific C compounds may release previously sorbed P and make P more plant-available, crops which contribute to high soil C levels could play an important role in soil P cycling. The objectives of this study were to determine (1) whether rotation crops had different amounts of root growth, (2) whether different amounts of root growth among the crop species could be related to different levels of soluble soil C and (3) whether there were differences in P concentration among the soils under different crops that could be related to soluble C soil concentration. Roots and soil from potato (Solanum tuberosum L.), barley (Hordeum vulgare L.), soybean (Glycine max (L.) Merr.), and a forage consisting of alfalfa (Medicago sativa L.) and timothy (Phleum pretense L.) were sampled from the Aroostook Research Farm in Presque Isle, Maine, during the summers of 2003 and 2004 to determine root length density (RLD) and soluble C and P concentrations. Half of the sampled plots were amended with beef manure and half were not amended. Barley and forage consistently had higher RLD than potato or soybean crops. Barley and forage typically had higher concentrations of soluble soil C than potato or soybean, but the differences were significant at only three of the five sampling dates. RLD was significantly correlated to soluble C (r=0.56) only for amended soils on the August 2003 sampling date. For other dates r values were non-significant and ranged from 0.32 to 0.49. As with soil C, soluble soil P levels were typically higher in barley and forage than in potato or soybean crops. Significant differences were detected at four of the five sampling dates. Correlations between soluble C and soluble P were significant at two of the five sampling dates (r = 0.58 and 0.62) in amended soils and one of five sampling dates (r = 0.80) in unamended soils. Although the correlations between RLD and soluble C were not significant at every sampling date, the August 2003 data do suggest a possible effect of roots on soluble C. In addition, significant correlations between soluble C and soluble P at several sampling dates suggest a relationship between these parameters. Therefore cropping systems that include crops with higher amounts of root growth may promote increased soluble soil C levels and enhance P bioavailability.
Study of N-type Si delta doping on InP and In 0.53 Ga 0.47 As

Heavily doped N-type materials are important for the fabrication of optoelectronic devices like tunnel junctions in multi-junction solar cell applications1, avalanche photodiodes, and nipi doped super lattices2, etc.. Silicon has been widely usedas n-type dopant in MOCVD growths due to its low thermal diffusivity and the absence of any memory effect duringgrowth. However, using the traditional homogenous Si doping in bulk crystal growths is difficult to obtain a high dopingaround the level of -i' cm3. Woelk and Beneking reported that the doping efficiency of Si using Si2H6 is more than afactor of 10 lower for InGaAs on InP substrates compared to InP3. For the InGaAs, it is usually even a difficult task toreach the level of1O18 crri3.In homogenous doping process, the dopant is incorporated into the material during the host crystal growth. For a groupIV dopant like the Si, it can occupy either the group III or the group V lattice sites. Usually, when the Si doping flow islow, most of the Si atoms will take the group III site and the doped host will appear to be a lightly doped N-type materialafter the growth. However, when one is trying to obtain high doping by increasing the Si introduction considerably, moreand more Si atoms will take group V sites and the N doping level starts to decrease. This is the auto-compensation effectand this is why by simply increasing the Si input, we cannot further increase the N doping. And with further increasingthe Si input, the material surface morphology will become very bad which is attributed to the formation of Si precipitatesduring the growth. More and more Si atoms may form neutral clusters rather than becoming incorporated as electricallyactive donors in the lattice.To get Si N-type doping level in InP and InGaAs as high as 1O19 cni3, we have to consider using the so-called deltadoping technique. Delta doping or planar doping, which confines dopants in a dopant plane between the host materialemerges as a promising technique to fabricate novel devices4. A principal method used to achieve the delta-function-like
An Evaluation of Some Tests of Trend in Contingency Tables

Abstract Consider an r × c contingency table under the full multinomial model in which each classification is ordered. The problem is to test the null hypothesis of independence against the alternative that all local log odds ratios are nonnegative with at least one local log odds ratio positive. A number of tests have been proposed for this problem, including the Goodman–Kruskal gamma test; a family of linear tests studied by Agresti, Mehta, and Patel; and a test based on “C–D,” the difference of concordant and discordant pairs in the table. In this article we show that all of these tests can be improved on in some sense for most cases. In fact the preceding tests sometimes are inadmissible in a strict sense. Furthermore, we show by example that in some cases improved tests can yield substantially improved power functions. We suggest a test based on a linear statistic similar to that presented by Agresti, Mehta, and Patel but that is followed up with a test that orders points by their probabilities on sa...
Kinetic response of an oxygen-selective electrode evaluated for the quantification of oxygen

Abstract An evaluation of the transient response of a membrane-based amperometric electrode for the quantification of oxygen in aqueous and gaseous phases is described. Data collected during the early part of the responses are used to compute the steady-state signals that would be measured if the responses were monitored to steady state. Both first-order and variable-order models were used successfully to fit data for aqueous samples; only the variable-order model worked successfully with data for gaseous samples. Because the shapes of response curves did not permit steady-state signals to be measured, comparisons are based on measured values of current at fixed times in each response. The slopes of computed vs. measured signals varied from 0.90 to 1.03 for fits of data over 3–5 half-lives with both models. Calibration graphs of computed current vs. concentrations were linear for similar fitting ranges and the least-squares parameters were similar to those for current measured at different fixed points in time.
The effect of pipe diffusion on harper-dorn creep at low stresses

Rappel des 3 principaux mecanismes de fluage et des equations correspondantes, le fluage selon Harper-Dorn etant generalement associe a un processus dominant de dislocation intergranulaire. Comparaison de la theorie avec les resultats experimentaux obtenus sur Tiα et Fe pur. Construction des cartes des mecanismes de deformation
An analytic generalized inverse for common‐depth‐point and vertical seismic profile traveltime equations

This paper presents an analytic formula for the generalized inverse matrix associated with vertical seismic profile (VSP) and common‐depth‐point (CDP) traveltime equations. Its functional form explicitly depends upon the source‐receiver geometry and its validity is restricted to horizontally layered earth models where there is negligible ray bending. The importance of the generalized inverse is that it can be used to derive closed‐form expressions for the covariance matrix, condition number, resolution matrix, and average inverse eigenvalues for the traveltime equations; these formulas are useful in designing source‐receiver geometries which optimize velocity reconstruction by traveltime inversion. These formulas also provide a fundamental understanding of some resolution limitations associated with earth tomography experiments. Previously, resolution characteristics of tomographic inversions were usually estimated by empirical computer tests on specialized earth models. Some specific conclusions drawn fr...
Longitudinal variability of methane and ammonia bands on Saturn

A total of 129 spectra of the center of the disk of Saturn were obtained in March 1980 in order to search for possible longitudinal variations in the CH4 6190 and NH3 6450 bands. The spectra were reduced to reflectivities, and the band equivalent widths were measured using a blind, automated continuum fitting technique. The methane and ammonia equivalent widths are well correlated with each other. There are some latitude regions in which both bands show enhanced absorption and some latitudes in which both bands are weaker than the average. The continuum reflectivity is quite constant with latitude and shows no apparent correlation with molecular band equivalent width. The observed variations may be explained by a longitudinal variation in the altitude of the top of the thick cloud of about + or - 2 km from the mean.
Ion transport regulation by P2Y receptors, protein kinase C and phosphatidylinositol 3-kinase within the semicircular canal duct epithelium

The ionic composition of the luminal fluid in the vestibular labyrinth is maintained within tight limits by the many types of epithelial cells bounding the lumen. Regulatory mechanisms include systemic, paracrine and autocrine hormones along with their associated intracellular signal pathways. The epithelium lining the semicircular canal duct (SCCD) is a tissue that is known to absorb sodium and calcium and to secrete chloride. Transport function was assessed by measurements of short circuit current (I sc ) and gene transcript expression was evaluated by microarray. Neither ATP nor UTP (100 microM) on the apical side of the epithelium had any effect on I sc . By contrast, basolateral ATP transiently increased I sc and transepithelial resistance dropped significantly after basolateral ATP and UTP. P2Y2 was the sole UTP-sensitive purinergic receptor expressed. I sc was reduced by 42%, 50% and 63% after knockdown of α-ENaC, stimulation of PKC and inhibition of PI3-K, while the latter two increased the transepithelial resistance. PKCdelta, PKCgamma and PI3-K were found to be expressed. These observations demonstrate that ion transport by the SCCD is regulated by P2Y2 purinergic receptors on the basolateral membrane that may respond to systemic or local agonists, such as ATP and/or UTP. The sodium absorption from endolymph mediated by ENaC in SCCD is regulated by signal pathways that include the kinases PKC and PI3-K. These three newly-identified regulatory components may prove to be valuable drug targets in the control of pathologic vestibular conditions involving dysfunction of transport homeostasis in the ear, such as Meniere's disease.
Design of an imaging microscope for soft X-ray applications

An imaging soft X-ray microscope with a spatial resolution of 0.1 micron and normal incidence multilayer optics is discussed. The microscope has a Schwarzschild configuration, which consists of two concentric spherical mirrors with radii of curvature which minimize third-order spherical aberration, coma, and astigmatism. The performance of the Stanford/MSFC Cassegrain X-ray telescope and its relevance to the present microscope are addressed. A ray tracing analysis of the optical system indicates that diffraction-limited performance can be expected for an object height of 0.2 mm.
Does Residency Training Improve Performance of Physical Examination Skills

ABSTRACT Background Few studies use objective structured clinical examinations (OSCEs) to measure physical examination skills of internal medicine residents. Little is known about performance by year of residency training. Purpose To determine differences between postgraduate year (PGY)-1 and PGY-3 residents on performance and comfort of physical examination skills. Methods In a cross-sectional study, we tested 16 PGY-1 (weeks 0 and 4) and 8 PGY-3 internal medicine residents with a five-station OSCE. Results PGY-3 residents performed better than PGY-1 week 0 residents ( P = 0.03) but not PGY-1 week 4 residents ( P = 0.42). PGY-1 resident performance improved after 1 month of inpatient wards experience ( P P = 0.003) but not PGY-1 week 4 residents ( P = 0.10). Conclusions Senior residents performed better and were more confident on physical examination skills, but the difference disappeared after 1 month of internship. This calls into question how much further learning occurs with physical examination throughout residency training.
Army requirements for micro and nanotechnology-based sensors in weapons health and battlefield environmental monitoring applications

The Army Aviation and Missile Research, Development, and Engineering Center (AMRDEC) and the Army Research Laboratory (ARL) have initiated a joint advanced technology demonstration program entitled "Prognostics/Diagnostics for the Future Force (PDFF)" with a key objective of developing low or no power embedded sensor suites for harsh environmental monitoring. The most critical challenge of the program is to specify requirements for the embedded sensor suites which will perform on-board diagnostics, maintain a history of sensor data, and forecast weapon health. The authors are currently collaborating with the PDFF program managers and potential customers to quantify the requirements for remotely operated, micro/nano-technology-based sensors for a host of candidate weapon systems. After requirements are finalized, current micro/nanotechnology-based temperature, humidity, g-shock, vibration and chemical sensors for monitoring the out-gassing of weapons propellant, as well as hazardous gaseous species on the battlefield and in urban environments will be improved to meet the full requirements of the PDFF program. In this paper, performance requirements such as power consumption, reliability, maintainability, survivability, size, and cost, along with the associated technical challenges for micro/nanotechnology-based sensor systems operating in military environments, are discussed. In addition, laboratory results from the design and testing of a wireless sensor array, which was developed using a thin film of functionalized carbon nanotube materials, are presented. Conclusions from the research indicate that the detection of bio-hazardous materials is possible using passive and active wireless sensors based on monitoring the reflected phase from the sensor.
Preseismic velocity changes observed from active source monitoring at the Parkfield SAFOD drill site

Measuring stress changes within seismically active fault zones has been a long-sought goal of seismology. Here we show that such stress changes are measurable by exploiting the stress dependence of seismic wave speed from an active source cross-well experiment conducted at the SAFOD drill site. Over a two-month period we observed an excellent anti-correlation between changes in the time required for an S wave to travel through the rock along a fixed pathway--a few microseconds--and variations in barometric pressure. We also observed two large excursions in the traveltime data that are coincident with two earthquakes that are among those predicted to produce the largest coseismic stress changes at SAFOD. Interestingly, the two excursions started approximately 10 and 2 hours before the events, respectively, suggesting that they may be related to pre-rupture stress induced changes in crack properties, as observed in early laboratory studies.
Towards the Replication of xDNA, a Size-expanded Unnatural Genetic System

Here we study the viability of an unnatural genetic system with size-expanded geometry (xDNA). xDNA contains base pairs 2.4 A larger than those of natural DNA. The expanded geometry is expected to be problematic for the natural high-fidelity replication machinery required to process genetic information. However, initial studies with a variety of DNA polymerases are promising in demonstrating replication of these unnatural bases. The results suggest the future possible viability of fully functional unnatural genetic systems, and give insight into the steric limits of some natural DNA polymerases.
Identification of mammalian sperm surface antigens: II. Characterization of an acrosomal cap protein and a tail protein using monoclonal anti-mouse sperm antibodies

Abstract Monoclonal anti-mouse sperm antibodies have been produced by fusing mouse myeloma cells with spleen cells from rats immunized with epididymal sperm of C3H mice. Immunoprecipitation and immunoperoxidase techniques showed that one such monoclonal antibody, AMS IV-33, recognized a 200 000 dalton protein localized on the acrosomal cap of the sperm cell. Two other monoclonal antibodies AMS IV-54 and -76, reacted with a 68 000 dalton component on the surface of the sperm tail. Both antigenic targets were species specific and were present in about equal amounts on sperm from several different strains of mice. The tail protein was sperm specific, whereas the antibody reacting with the acrosomal cap protein also appeared to react somewhat with antigens present in other mouse tissues.
Fundamental defect centers in glass: Si 29 hyperfine structure of the nonbridging oxygen hole center and the peroxy radical in a -Si O 2

$^{29}\mathrm{Si}$ hyperfine structure determinations for two fundamental oxygen-associated paramagnetic defect centers in high-purity amorphous silica complete the characterization of the nonbridging oxygen hole center and the peroxy radical by demonstrating in each case that the oxygen(s) trapping the unpaired spin are bonded to only one silicon in the glass network. It is shown that these findings place important constraints on the supposed precursors of the peroxy radical in $a$-Si${\mathrm{O}}_{2}$.
Monochromatic Camera for Photography in the Far Ultraviolet

An ultraviolet monochromatic camera has been constructed which avoids the use of quartz or lithium fluoride optics. The camera makes use of two gratings mounted in the Wadsworth-type arrangement in such a way that the dispersions neutralize. The instrument is, thus, a double monochromator, a feature helpful in reducing stray light. Three forms of the camera have been developed, differing only in the manner in which the focus of the final image is achieved.The image is not purely monochromatic but contains a narrow range of wavelengths determined mostly by grating constants and slit widths. A description of the chromatic composition of the image is given and possible applications, including the study of solar limb darkening in Lyman-alpha radiation, are discussed.
Minitack Introduction: Advances in Teaching and Learning Technologies

The Advances in Teaching and Learning Technologies Minitrack serves as an outlet for research dealing with theories, tools, tool development, enabling platforms, communication media, distance learning, supporting infrastructures, user experiences, research methods, social impacts, and measurable outcomes as they relate to improving teaching and learning. As such, this Minitrack is intended to include all aspects of learning from the original inceptions of theories and tools through the measurement of learning outcomes. Usage environments range from same-time, same-place to anytime, anyplace that increase interactions among the learners and the teachers or facilitators. This is the fourth year of this Minitrack which resulted from the combination of the Asynchronous Learning Networks, Next Generation of Learning Platforms, and Technology Supported Learning Minitracks. The papers this year are organized into three presentation sessions, each focusing on a different aspect of technologies for teaching and learning.
New ideas about parasites

Evolutionary Biology of Parasites. By Peter W. Price. Pp.237. (Princeton University Press: 1980.) Hardback $22, £9.70; paperback $8.75, £3.80.
Cost-Effectiveness of Vertebral Fracture Assessment to Detect Prevalent Vertebral Deformity and Select Postmenopausal Women With a Femoral Neck T-Score > −2.5 for Alendronate Therapy: A Modeling Study

Abstract Most fractures occur in postmenopausal women who do not have osteoporosis by bone density criteria (T-score>−2.5). Prevalent vertebral deformity is a strong risk factor for incident fractures independent of bone mineral density, yet the majority of these deformities are clinically unapparent. Spine imaging on a dual-energy densitometer, called vertebral fracture assessment (VFA), can accurately detect these deformities. The purpose of this modeling study was to estimate the lifetime societal costs and health benefits of VFA and confirmatory follow-up radiography to detect prevalent vertebral deformity in osteopenic (T-score −1.5, −2.0, or −2.4) postmenopausal women, followed by anti-resorptive drug therapy for those with one or more deformities. We compared three strategies; no initial drug therapy, 5 yr of initial alendronate therapy, or VFA followed by 5 yr of alendronate therapy in those with one or more vertebral deformities confirmed on radiography (VFA strategy). Results for the base-case analyses showed that the cost per quality adjusted life year (QALY) gained for the VFA strategy relative to no initial drug therapy ranged from $18,000 (for a 60-yr-old with a femoral neck T-score of −2.4) to $77,000 (for an 80-yr-old with a T-score of −1.5). VFA with selective confirmatory radiography is cost-effective, assuming a societal willingness to pay per QALY gained of $50,000, for postmenopausal women aged 60 to 80 yr with femoral neck T-scores between −2.0 and −2.4, and for women age 60 or 70 yr with a T-score of −1.5. Assuming a societal willingness to pay of $100,000 per QALY gained, VFA is also cost-effective for women age 80 yr with a T-score of −1.5. These conclusions are robust to reasonable changes in fracture rates, assumed fracture disutility, discount rates, relative risk of fracture attributable to vertebral deformity, alendronate cost, and drug adherence.
A systems rationale for the selection or design of tribological surface coatings

Tribological surface coatings have been used to control wear or friction. There are many interacting processes including friction, wear, environment, thermal stresses and mechanical stresses as well as a variety of operating variables that should be part of the design logic. The number, complexity and level of the processes suggest that a systems approach could be helpful. A design logic checklist was prepared at a hierarchy level considered to be useful to both designers and researchers. A review of the processes indicated that composite design technology could be applied and that the coating methods of chemical vapor and vacuum sputter ion deposition were promising for designed coatings as they allow immobilization of the original surface defects and can provide a transitional region of graded interfaces that help to control the system's determinant processes (environment, thermal and mechanical) as well as the friction and wear.
Critical cooling rate for growth from large, low prandtl number solutions: GaAs

Abstract Nucleation-resistant crucible materials are the best suited to the sustained growth of stationary suspended GaAs seeds from large solutions of As in Ga (Ga : As). If spurious nucleation occurs on the crucible walls and the resulting crystals are cooler than the seed, the competition for growth between the seed and spurious crystals can cause the seed to dissolve. Low Prandtl number solutions such as Ga : As are particularly susceptible to dissolution because convection provides good communication between the seed and spurious crystals. The cooling rate of a 5000 g Ga : As solution contained in a graphite crucible with an aspect ratio of 1 must exceed 0.75°C h-1 to prevent dissolution. A phenomenological expression for the critical cooling rate Cc was derived.
Numerical parallel algorithms for large-scale nanoelectronics simulations using NESSIE

A new high performance parallel algorithms to enhance the numerical efficiency of the self-consistent procedure was being proposed. In NESSIE, the linear systems are currently solved on a uniprocessor using a preconditioned Krylov subspace iterative method. In order to compute the electron density, one needs to repeat this procedure for all the energy levels (of the order 103+). This can be trivially done independently on each processor of a Linux cluster using MPI directives. One advantage of this parallel procedure is that the communications between the processors are minimal. A significant drawback, however, to this simplistic solution strategy is that it may not be possible for each processor, with its limited local memory, to handle huge linear systems. For very large systems as outlined above, it is essential to adopt a strategy in which all processors of a high-end computing platform, cooperate on solving a single system. Towards the goal the following were developed and applied (i) a parallel hybrid linear solver SPIKE that represents an improvement over the classical direct solvers of ScaLAPACK, (ii) a parallel trace-minimization algorithm TRACEMIN that is superior to Lanczos, subspace iteration, and LAPACK schemes for computing the lowest eigenpairs.
Mode of Action of the Phytoalexin Desoxyhemigossypol against the Wilt Pathogen, Verticillium dahliae

Abstract The phytoalexin desoxyhemigossypol (dHG) is formed in cotton roots and stems in response to infection by the wilt pathogen Verticillium dahliae . At 6.1 μg/ml, desoxyhemigossypol reduces growth of V. dahliae by approximately 75%. Desoxyhemigossypol appears to decompose by an H 2 O 2 -mediated free radical process. We now report that catalase at 500 U/ml significantly reduces the toxicity of dHG, further implicating H 2 O 2 as a required intermediate for the expression of dHG toxicity. Glutathione (0.1 m M ) and superoxide dismutase (SOD) (1700 U/ml) also reduce the toxicity of dHG with SOD having the smallest effect. A proposed decomposition scheme of dHG provides a rational for the involvement of H 2 O 2 , free radicals such as HO . , or free radicals of dHG in the toxicity of this phytoalexin.
The reaction of diborane with boron trichloride in the presence of ethers—The chloroborane etherates

Abstract Diborane does not react to any significant extent with boron trichloride in the absence of ethers. In the presence of ethers (dimethyl ether, diethyl ether, diglyme, tetrahydrofuran and tetrahydropyran) reaction readily occurs at room temperatures to form chloroborane etherates, as indicated by the equations: B2H6 + BCl3 + 3R2O → 3H2ClB·OR2B2H6 + 4BCl3 + 6R2O → 6HCl2B·OR2 These chloroborane etherates may also be synthesized from the alkali metal borohydrides in accordance with the reactions: MBH4 + BCl3 + 2R2O →: 2H2ClB·OR2 + NaClMBH4 + 3BCl3 + 4R2O →: 4HCl2B·OR2 + NaCl Their formation accounts for the low yield of diborane realized in treating the alkali metal borohydrides with an excess of boron trichloride in ether solutions. A number of the chloroborane etherates have been isolated and characterized. They react with olefins to form organoborane derivatives and to reduce the carbonyl groups in typical ketones, but not in esters.
Optimal ordering policy of a sequencing model

In this note, we are concerned with the study of a sequencing problem applicable to situations where the optimal choice amongn! sequences is sought. A class of sequencing problems is proposed. Based on the adjacent pairwise interchange of two objects, necessary and sufficient conditions for an optimal ordering policy are given. Examples from the literature are considered and shown to be special cases of the proposed model. The results of this paper improve recent results given in Refs. 1 and 2.
Properties of black lipid membranes of chloroplast pigments.

Abstract 1. 1. Physical properties of black lipid membranes formed from chlorophylls and chloroplast pigments in aq. NaCl solutions have been determined. The properties of chlorophyll black lipid membranes show significant differences from those black lipid membranes produced from phospholipids, synthetic surfactants, or oxidized cholesterol. 2. 2. The chlorophyll black lipid membranes as measured by a reflectance technique have a thickness of about 105 ± 5 A . Possible sources of error in assessing the membrane thickness are discussed. 3. 3. The bifacial tension of the chlorophyll black lipid membrane in 0.1 M NaCl, as measured by the bulging method, was found to be 3.8–4.5 dynes/cm. 4. 4. The permeability to water of chlorophyll black lipid membranes has been determined by an osmotic flow method. NaCl was used as the solute. A value 51 μ/sec has been obtained for the permeability coefficient. The effect of temperature on water permeability has also been investigated. The Arrhenius activation energy has been found to be 4.2 kcal/mole. 5. 5. Electrical parameters of chlorophyll black lipid membranes have been measured in various NaCl solutions (10−3 to 1 M). In dilute solutions (10−2.5 M or less) the d.c. resistance was 1.10 6 −3.10 6 Ω· cm 2 . At higher concentrations, the resistance of the membrane was lower by a factor of ten. The temperature dependence of membrane resistance has been measured. A value 15.9 ± 0.3 kcal/mole has been obtained for the activation energy. 6. 6. It is concluded that black lipid membranes produced from chloroplast pigments are useful model systems for further investigation which may give insight into the processes relevant to photosynthesis.
THE BACILLUS SUBTILIS FLAGELLAR REGULATORY PROTEIN SIGMA D : OVERPRODUCTION, DOMAIN ANALYSIS AND DNA-BINDING PROPERTIES

Flagellar biosynthesis requires an alternative sigma (σ) subunit of RNA polymerase to allow recognition of the promoters for flagellin and other late genes of the flagellar regulon. We have now overproduced and characterizedBacillus subtilisσD: the prototype of the S28family of flagellar σ factors. Limited protease digestion studies indicate that σDcontains an amino-terminal domain, comprising conserved regions 1.2 and 2, and a carboxyl-terminal domain containing conserved regions 3.2 and 4. The protease-sensitive region between these two domains correlates with a region of very low sequence conservation among bacterial σ factors. Unlike the primary σ factor, σDbinds to DNA. In non-denaturing polyacrylamide gel electrophoresis the σD-DNA complex has an apparent equilibrium dissociation constant of 1 μM. Binding of σDto the promoter for flagellin, PD-6, appears to lead to an altered DNA structure near the −35 and −10 recognition elements as detected by DNase I footprinting and by the enhanced reactivity of several bases to dimethylsulfate.f2
Vibrational analysis of the green-yellow system of La18O

Using a low-pressure arc source the band spectrum of La18O has been obtained. The heads between 5200-6300 AA were analysed and the vibrational constants are: sigma e=17884.89 cm-1, omega e'=696.00 cm-1, omega e' chi e'=1.83 cm-1, omega e"=775.53 cm-1, and omega e" chi e"=2.06 cm-1. With these figures the recalculated positions of the bands are in excellent agreement with the experimental values.
Mechanisms of Adsorbent Action in Beverage Stabilization

Unstabilized apple juice (unfermented cider clarified by centrifugation and filtration) was treated with various amounts of bentonite, silica gel, or polyvinylpolypyrrolidone (PVPP). The effectiveness of these adsorbents was assessed by measurements of haze-active (HA) protein and HA polyphenol. Bentonite was very effective in removing HA protein, taking out about ∼92% at the highest treatment level, while silica gel removed only ∼25%. Bentonite and silica gel had little effect on HA polyphenol. PVPP took out essentially all of the HA polyphenol at the highest treatment level and reduced HA protein somewhat. These results are quite different from those obtained previously with beer but can be explained by the large differences in protein to polyphenol ratio between the two beverages. Keywords: Haze; protein; polyphenol; silica gel; bentonite; PVPP
Genetic and environmental determinants of musical ability in twins

Analyses of musical ability data from the Loehlin and Nichols National Merit Scholarship study are presented. Musical ability is indexed by four measures: interest in a profession in music, performance in school, performance outside of school, and receiving honors in music. These variables pose a challenge for behavior genetic analysis since they do not conform to the assumptions of traditional linear models. For example, there is a dependent relationship between the honors and the performance variables; one cannot obtain honors without performance. Several methods were employed to deal with these relationships, and the following conclusions appeared regardless of the method used. First, twin correlations were always high, ranging from 0.44 to 0.90 in monozygotic (MZ) twins and from 0.34 to 0.83 in dizygotic (DZ) twins. Second, although there was evidence for heritable variation, the effects of common environment were almost always larger than the effects of heredity. Third, marital assortment was not of sufficient magnitude to account for these common environment effects. In the young adults in this sample, musical ability is influenced more by shared family environment than by shared genes.
Patellofemoral Anatomy and Biomechanics

Patellofemoral disorders are common. There is a broad spectrum of disease, ranging from patellofemoral pain and instability to focal cartilage disease and arthritis. Regardless of the specific condition, abnormal anatomy and biomechanics are often the root cause of patellofemoral dysfunction. A thorough understanding of normal patellofemoral anatomy and biomechanics is critical for the treating physician. Recognizing and addressing abnormal anatomy will optimize patellofemoral biomechanics and may ultimately translate into clinical success.