cssi/SciSciGPT-SciSciNet huggingface dataset:
Secondary Effects of Soil Venting and Potential Low‐Cost Enhancements

Soil venting, in addition to removing volatile organic compounds, has secondary effects on soil temperature and moisture content. A simple enthalpy balance model is used to illustrate the magnitude and direction of temperature and moisture content changes in the soil during ordinary venting and with several potential modifications to venting. Because of the important of latent heat of vaporization, injection of warm, dry air into the subsurface is generally ineffective in heating the soil. In contrast, injection of humidified, slightly heated air is found to result in significant soil warming even at low flow rates. Soil warming is thought to be an important mechanism for enhancing remediation, particularly in the final or tail stage of cleanup where concentrations slowly decline with time. A variety of soil venting alternatives are simulated at hypothetical sites in Chicago, Illinois, and Tucson, Arizona, including simple humidification, humidification with solar heating, and venting under positive pressure. All three methods result in higher final soil temperatures than the control case of normal soil venting. Humidification of the input air at the rates applied does not result in significant change in average soil moisture content or saturation of the soil with water.
New upper bounds for selection

The worst-case, minimum number of comparisons complexity Vi(n) of the i-th selection problem is considered. A new upper bound for Vi(n) improves the bound given by the standard Hadian-Sobel algorithm by a generalization of the Kirkpatrick-Hadian-Sobel algorithm, and extends Kirkpatrick's method to a much wider range of application. This generalization compares favorably with a recent algorithm by Hyafil.
Aircraft Observations of the Marine Boundary Layer Adjustment near Point Arguello, California

AbstractNortherly winds set up by synoptic conditions are persistent in the marine boundary layer (MBL) off the California coast from late spring through summer. Wind, pressure, and MBL height are modulated as the low-level flow impinges on the points and capes along the California coast. The Precision Atmospheric Marine Boundary Layer Experiment was conducted in May and June of 2012 with the primary goal to directly measure the dynamics responsible for the wind field near Point Arguello and Point Conception. Detailed measurements of the horizontal pressure field within the MBL were made using the University of Wyoming King Air research aircraft. Airborne measurements made during cases of strong northerly wind show an abrupt adjustment of the MBL near Point Arguello, including a modulation of the horizontal pressure gradient force and a near collapse of the MBL. Airborne lidar measurements complement measurements of the horizontal pressure field and help to elucidate the large changes in the MBL height in...
Multivariate symmetry via projection pursuit

Blough (1985,Ann. Inst. Statist. Math.,37, 545–555) developed a multivariate location region for a randomp-vectorX. The dimension of this region provides information on the degree of symmetry possessed by the distribution ofX. By considering all one-dimensional projections ofX, it is possible to ascertain the dimension of the location region. Projection pursuit techniques can therefore be used to study symmetry in multivariate data sets. An example from an Entomology investigation is presented illustrating these methods.
An estimation of the condensation rates in three severe storm systems from satellite observations of the convective mass flux

A technique was developed for estimating the condensation rates of convective storms using satellite measurements of cirrus anvil expansion rates and radiosonde measurements of environmental water vapor. Three cases of severe convection in Oklahoma were studied and a diagnostic model was developed for integrating radiosonde data with satellite data. Two methods were used to measure the anvil expansion rates - the expansion of isotherm contours on infrared images, and the divergent motions of small brightness anomalies tracked on the visible images. The differences between the two methods were large as the storms developed, but these differences became small in the latter stage of all three storms. A comparison between the three storms indicated that the available moisture in the lowest levels greatly affected the rain rates of the storms. This was evident from both the measured rain rates of the storms and the condensation rates estimated by the model. The possibility of using this diagnostic model for estimating the intensities of convective storms also is discussed.
A Staphylococcus aureus pore-forming toxin subverts the activity of ADAM10 to cause lethal infection in mice

Staphylococcus aureus is a major cause of human disease, responsible for half a million infections and approximately 20,000 deaths per year in the United States alone. This pathogen secretes α-hemolysin, a pore-forming cytotoxin that contributes to the pathogenesis of pneumonia. α-hemolysin injures epithelial cells in vitro by interacting with its receptor, the zinc-dependent metalloprotease ADAM10 (ref. 6). We show here that mice harboring a conditional disruption of the Adam10 gene in lung epithelium are resistant to lethal pneumonia. Investigation of the molecular mechanism of toxin-receptor function revealed that α-hemolysin upregulates ADAM10 metalloprotease activity in alveolar epithelial cells, resulting in cleavage of the adherens junction protein E-cadherin. Cleavage is associated with disruption of epithelial barrier function, contributing to the pathogenesis of lethal acute lung injury. A metalloprotease inhibitor of ADAM10 prevents E-cadherin cleavage in response to Hla; similarly, toxin-dependent E-cadherin proteolysis and barrier disruption is attenuated in ADAM10-knockout mice. Together, these data attest to the function of ADAM10 as the cellular receptor for α-hemolysin. The observation that α-hemolysin can usurp the metalloprotease activity of its receptor reveals a previously unknown mechanism of pore-forming cytotoxin action in which pathologic insults are not solely the result of irreversible membrane injury and defines ADAM10 inhibition as a strategy to attenuate α-hemolysin-induced disease.
Anastomotic pseudoaneurysm of the ventricle after homograft placement in children

A pseudoaneurysm of the right ventricle was diagnosed postoperatively in 8 patients between 1986 and 1992. One pseudoaneurysm formed after placement of a Carpentier-Edwards conduit and the other seven arose after placement of a homograft between the right ventricle and the pulmonary artery. Both aortic (n = 3) and pulmonary (n = 4) homografts had been used. In 6 patients, the homografts had been augmented proximally with Dacron, Gore-Tex, or pericardium. Pseudoaneurysms originated between the augmentation patch and the homograft in 4 patients, between the homograft or conduit and the myocardium in 3 patients (1 patient with and 2 without an augmentation patch), and between the patch and the myocardium in 1 patient. The prior operations performed were placement of a palliative conduit for tetralogy of Fallot with pulmonary atresia (n = 5), repair of truncus arteriosus (n = 2), and repair of absent pulmonary valve syndrome (n = 1). Pseudoaneurysms were discovered from 5 weeks to 4 years after the operation. Symptoms were present in 3 patients; in the others, diagnosis was made during follow-up on the basis of routine imaging studies. Symptoms, when present, were due to compression of surrounding mediastinal structures. Pseudoaneurysms ranged in diameter from 1.0 to 5.0 cm. Echocardiography and color-flow mapping reliably identified the pseudoaneurysm in the 6 patients in whom it was performed. Characteristic features included a well-defined, narrow aneurysm neck leading to an extracardiac echo-free space. Color-flow mapping demonstrated to-and-fro flow through the neck of the aneurysm.(ABSTRACT TRUNCATED AT 250 WORDS)
Chronic and cyclical neuronal loss in hippocampal slice cultures following transient inhibition of the type 1 isoform of superoxide dismutase.

Abstract Increased oxidative stress contributes to chronic neurodegenerative diseases, yet the underlying mechanisms are poorly understood. Hippocampal slice cultures prepared from 20–30-day-old mice or rats were used to model chronic neuronal loss following oxidative stress. Neuronal loss was initiated by inhibition of the antioxidant enzyme, superoxide dismutase type 1 (SOD1), using the copper chelator diethyldithiocarbamate (DDC). Continuous DDC treatment of slice cultures induced delayed neuronal loss beginning at 9 days of treatment that lasted for over 4 weeks. Neuronal loss was not uniform, rather it was cyclic: peaking at days 9–13 and at days 19–21 after DDC exposure. Neuronal loss was significantly attenuated in slice cultures that overexpress SOD1, suggesting that SOD1 inhibition was responsible. Inhibitors of nitric oxide synthase also attenuated DDC-induced neuronal loss. Chronic neuronal loss, however, did not require continuous SOD1 inhibition. Application of DDC for 13 days resulted in loss of SOD1 activity. Removal of DDC restored SOD1 activity, yet the cycles of cell loss continued until no neurons remained. Astrocyte activation was observed following the second peak of neuronal loss. Media conditioned by cultures following DDC removal induced neuronal loss and microglial activation in recipient cultures. These data suggest that slice cultures released soluble neurotoxic factor(s) following DDC removal. These data also suggest that a transient reduction of SOD1 activity leads to chronic loss of hippocampal neurons. This neuronal loss may be mediated by soluble neurotoxic factor(s) and microglial activation. Cyclical neuronal loss may also underlie chronic neurodegeneration in vivo.
Efficient solution of population balance equations with discontinuities by finite elements

Two refinements of Galerkin's method on finite elements were evaluated for the solution of population balance equations for precipitation systems. The traditional drawbacks of this approach have been the time required for computation of the two-dimensional integrals arising from the aggregation integrals and the difficulty in handling discontinuities that often arise in simulations of seeded reactors. The careful arrangement of invariant integrals for separable aggregation models allows for a thousandfold reduction in the computational costs. Discontinuities that may be present due to the hyperbolic nature of the system may be specifically tracked by the method of characteristics. These discontinuities will arise only from the initial distribution or nucleation and are readily identified. A combination of these techniques can be used that is intermediate in computational cost while still allowing discontinuous number densities. In a case study of calcium carbonate precipitation, it is found that the accuracy improvement gained by tracking the slope discontinuity may not be significant and that the computation speed may be sufficient for dynamic online optimization.
Atmospheric Circulation During December 1970 Through February 1971

Abstract National Meteorological Center wind data from December 1970 to February 1971 were used to compute the 90-day winter mean eddy kinetic energy, and the energy exchange between waves and between waves and zonal mean flows at 200 mb, over mid-latitude (33.0–48.1°N), subtropical (10.0–28.7°N) and tropical (5.0°N–14.8°S) belts. In the mid-latitude (subtropical) belt, waves of wavenumbers 1–10 lose (gain) energy to (from) zonal mean flows with large contributions from wavenumbers 2–3 and 5–7. Energy exchanges over the tropical belt are quite different from those in the mid-latitude and subtropical belts with conspicuously small wave-zonal flow interaction and somewhat larger wave-wave nonlinear interactions. Wavenumber 8 receives substantial energy via wave-wave interaction with other waves in both the sub-tropical and tropical belts. Sometimes the 200 mb eddy kinetic energy was well above its 90-day winter mean at all latitudinal belts. Such occasions were characterized by an extremely strong jet strea...
The Effect of Frequency Information on Actor-Entity Attributions

Seeing a person repeat a given behavior may increase perceptions of consistency. Therefore, frequency information may have an impact similar to consistency information. Our model, based on associative network theory, makes the opposite predictions: frequency information will decrease actor-attributions under low-consensus, low-distinctiveness; and decrease entity attributions under high-consensus, high-distinctiveness. Predicted information type by frequency interaction was significant.
Automatic detection and correction of repairs in human-computer dialog

We have analyzed 607 sentences of spontaneous human-computer speech data containing repairs (drawn from a corpus of 10,718). We present here criteria and techniques for automatically detecting the presence of a repair, its location, and making the appropriate correction. The criteria involve integration of knowledge from several sources: pattern matching, syntactic and semantic analysis, and acoustics.
The ion core in RNA folding

Metal ions that link phosphates and guanine bases are necessary for the folding of an RNA enzyme. A magnesium ion core may be a common feature of RNA structure.
What to report

The results of an empirical study made of the report-reading habits of a group of Westinghouse managers are presented. The author systematically documents two types of information: (1) how managers read reports; and (2) what managers look for in reports. Useful checklists for various types of reports are provided and a section on the responsibility of management in the reporting process is included.
Cystinuria presenting with acute renal failure and hyperkalemia

The Journal is attempting an experiment. Pediatric Nephrology is going to publish a series of educational quizzes, each of which comprises a case with a series of questions. The answers to the quizzes will not only contain the correct letter but will also contain references and a detailed explanation of the author’s reason for the answer. If you would like to participate and find out what the author thinks are the correct answers, please email Linda.BridgesHalcomb@UTSouthwestern.edu and state the month of the Journal for which you would like the answers. The answers will be sent back to you electronically. The reason for this approach is to save space in the Journal, and these cases may be used by some societies and boards as a method of furthering medical education in the future. We welcome your input and suggestions. The first case in this series is a patient who presented to the Children’s Medical Center of Dallas a couple of years ago. Case summary
Intradialytic exercise: A pilot program

Intradialytic exercise is both safe and beneficial for patients; however, worldwide, despite evidence to support its efficacy, it is underutilized. A pilot project in a large inner city hemodialysis unit demonstrated the benefits of introducing a program to improve physical function among the participants.
Bond strength of coatings applied by the flame plating technique

1. A method is proposed for determining the bond strength of deposits prepared by the flame plating technique. The method makes it possible to establish, from the bond strength of a deposit 0.2–0.3 mm thick, the bond strength of deposits ranging in thickness from 0.2 to 1–1.5 mm, with an accuracy of +-20%. 2. An analysis is made of the existing bond-strength tests for flame-plated deposits, resulting in the choice of an optimum procedure.
Psychiatric Diagnoses in Children with Alopecia Areata

ABSTRACT Objective To identify psychiatric diagnoses in a sample of 12 children with alopecia areata (AA), to assess the possible relationship between life stressors and AA and to correlate any consistent physical findings to psychiatric data. Method Twelve children with AA completed systematic psychiatric evaluations. The assessments included structured and semistructured interviews, rating scales, and parent checklists. Children had previously undergone immunological and endocrinological blood testing. Results Seven of the 12 subjects met criteria for anxiety disorders (including simple phobia) on structured interviews. An additional subject met criteria for dysthymia. Self-esteem measures indicated a high positive self-concept, and rating scales measuring anxiety and depression were within normal limits. No significant difference was found between mean number of positive or negative life events of children with AA compared with a normative sample. Conclusions Although structured interviews revealed a higher than expected rate of anxiety or depressive disorders in this small clinical sample, self-report rating scales and semistructured interviews did not support the conclusion that significant psychopathology was present.
Carbon and hydrogen isotope fractionation associated with the aerobic microbial oxidation of methane, ethane, propane and butane

Abstract Carbon isotope fractionation factors associated with the aerobic consumption of methane (C1), ethane (C2), propane (C3), and n-butane (C4) were determined from incubations of marine sediment collected from the Coal Oil Point hydrocarbon seep field, located offshore Santa Barbara, CA. Hydrogen isotope fractionation factors for C1, C2 and C3 were determined concurrently. Fresh sediment samples from two seep areas were each slurried with sea water and treated with C1, C2, C3 or C4, or with mixtures of all four gases. Triplicate samples were incubated aerobically at 15 °C, and the stable isotope composition and headspace levels of C1–C4 were monitored over the course of the experiment. Oxidation was observed for all C1–C4 gases, with an apparent preference for C3 and C4 over C1 and C2 in the mixed-gas treatments. Fractionation factors were calculated using a Rayleigh model by comparing the δ13C and δD of the residual C1–C4 gases to their headspace levels. Carbon isotope fractionation factors (reported in e or (α-1) × 1000 notation) were consistent between seep areas and were −26.5‰ ± 3.9 for C1, −8.0‰ ± 1.7 for C2, −4.8‰ ± 0.9 for C3 and −2.9‰ ± 0.9 for C4. Fractionation factors determined from mixed gas incubations were similar to those determined from individual gas incubations, though greater variability was observed during C1 consumption. In the case of C1 and C3 consumption, carbon isotope fractionation appears to decrease as substrate becomes limiting. Hydrogen isotope fractionation factors determined from the two seep areas differed for C1 oxidation but were similar for C2 and C3. Hydrogen isotope fractionation factors ranged from −319.9‰ to −156.4‰ for C1 incubations, and averaged −61.9‰ ± 8.3 for C2 incubations and −15.1‰ ± 1.9 for C3 incubations. The fractionation factors presented here may be applied to estimate the extent of C1–C4 oxidation in natural gas samples, and should prove useful in further studying the microbial oxidation of these compounds in the natural environment.
Behavioral treatment of obsessive-compulsive disorder in African Americans*

This paper reviews some important features in the presentation, diagnosis, and treatment of obsessive-compulsive disorder (OCD) in African Americans. Some adaptations to the behavioral treatment of OCD in African Americans are illustrated through the use of case examples. The growing awareness in psychology that cultural and ethnic issues are important factors in effective treatment planning forms the basis for the present paper. African Americans with OCD in particular have tended not to seek help in mental health settings, and there is little published research in this area. Thus, many clinicians and researchers may be unfamiliar with issues relevant to treatment issues of OCD in this population.
Effect of Continuous Arteriovenous Haemofiltration on Pharmacokinetics of Amrinone

This case report details the pharmacokinetic adjustments of an amrinone infusion in a paediatric patient who developed multiorgan system failure with anuric renal failure and was prescribed continuous arteriovenous haemofiltration. A significant proportion of clearance of amrinone is nonrenal. Near normal amrinone clearance can occur in patients with hepatic and renal dysfunction if continuous arteriovenous haemofiltration is used. Hepatic dysfunction with renal failure may require a reduction in the continuous amrinone infusion rate as previously reported for neonates.
Utility factors in articulation screening: Effeciency of selection and cost

Abstract Comparative study of the effeciencies of selection of several articulation screening tests in the kindergarden and first grades of five school districts showed that validities were relatively high. Important exceptions were noted. Means and standard deviations for times of administration of the tests were also determined. Differences in examiners' pass-fail criteria were discussed. Attention was directed to accounts in the literature that attribute significant differences between examiners' scores to experience in listening to defective articulation. Implications of the results for articulation screening in the public schools were drawn, and suggestions made for further study.
Transmission Capacity of Disk Storage Systems with Concurrent Arm Positioning

An organization for a disk storage system oriented toward multicomputer and shared computer applications is described, and a study is made of its effectiveness in accessing data. The disk file incorporates an independently positioned arm for accessing each disk, and the capability for concurrently controlling several positioners. Also, multiple data transmission channels can be provided between the disk file and a buffer unit. A criterion of maximum average transmission capacity is proposed for investigating the speed of accessing data with this organization. Probabilistic models for analyzing the queueing of positioned arms for access to a disk-buffer transmission channel are developed. With reasonable assumptions, the solution of the models is reduced to a small set of linear equations in terms of queue length probabilities. The transmission capacity is evaluated with parameter values typical of contemporary disk files. The principal conclusion is that the economic feasibility of more than three position controllers per disk-buffer channel is very doubtful in seeking the full effectiveness of this organization.
Stochasticity as an alternative to deterministic explanations for patterns of habitat use by birds

Stochasticity is rarely explicitly investigated as a determinant of patterns of habitat use, even though evidence of its influence would undermine support for deterministic models of habitat selection. To assess the role of stochasticity in generating patterns in habitat use, we compared observed patterns of year-to-year variation in habitat use of 20 bird species over five years with patterns randomly generated from null models with different biological constraints (i.e., abundance, territoriality, exclusion of unused habitat, site fidelity, and habitat preference). We were able to recreate patterns of variability in spatial distributions with one or more null models for 18 species, suggesting an important role of stochasticity. Although year- to-year variability could be modeled as a purely stochastic process for only four species, null models in which random variability was constrained by the influences of vegetation or site fidelity collectively matched the observed patterns of variability of all 18 species. Support for these two models suggested that factors that increase the likelihood of returning to a previously used area and thus limit the spatial extent of random territory placement can generate patterns similar to those we observed. Greater support for models with preference constraints (i.e., models that included bird-vegetation associations) over models with avoidance constraints (i.e., models that excluded areas that were never occupied) indicated that preference was the primary mode of habitat selection. Stochastic patterns in habitat use may have resulted from a weak relationship between habitat selection and habitat quality, influence of non-vegetation habitat features (e.g., climatic fluctuations), nonequilibrium conditions, and a greater influence of stochastic variation at small spatial and temporal scales. Alternatively, responses to environmental cues may have been deterministic, but in summation, these responses may have created variability in spatial distribution patterns that was indistinguishable from random variation. In such cases, we suggest that it may be easier to model variation in habitat use as a random process rather than using deterministic models that account for a multitude of environmental factors influencing habitat selection of birds. Regardless, stochasticity may play a larger role in generating patterns of habitat use than is often considered, and it deserves wider attention.
Ubiquinone redox status in brain in vitro.

—The redox status of ubiquinone (Q) as an index of mitochondrial respiratory chain activity in chopped telencephalon from the rat was investigated. With 12mm-glucose under aerobic conditions Q was 73% oxidized. Three mm-amytal and 2 μm-rotenone, inhibitors of mitochondrial NADH oxidation, resulted in Q being further oxidized by 14 and 16%, respectively. Thus, amytal and rotenone result in shifts in Q redox status of rat telencephalon slices in accord with the known site of action of these compounds in isolated mitochondria. However, under anaerobic conditions Q redox status shifted to 25% oxidized while incubation with 1 mm-NaCN resulted in a shift to only 58% oxidized. This discrepancy may result from concomitant inhibition in the supply of reducing equivalents to Q from substrate by NaCN or it may reflect a differential sensitivity of neuronal and glial mitochondria to NaCN. Evaluation of Q oxidation-reduction can be used to measure the effects of drugs and physiological perturbations on the redox status of the mitochondrial compartment of intact brain preparations.
Multiple shoot formation from almond embryos

Stimulation of multiple shoot formation from almond embryos using 6-benzylaminopurine was studied. Maximum shoot numbers and shoot growth were obtained with 2.5 μM in the growth medium. Continuous multiple shoot formation from cut shoots was also achieved.
Content-addressable memory for VLSI pattern inspection

In the template-set approach to VLSI pattern inspection, all patterns in a local window (i.e. a 5*5 array of pixels) that are allowed by the design rules are collected as a template set, and an image in the window centered at each pixel position is compared to the templates to determine whether the pattern is defective. To make this method practical, the number of acceptable templates must be reasonably small and template matching must be fast. By introducing don't-care conditions into the templates, the number of required templates was reduced. A maskable content-addressable memory was used to implement templates with don't-care conditions and to permit parallel comparison of an incoming pattern with all templates in the set. A custom VLSI chip was designed with a 2- mu m double-metal CMOS technology, which can perform parallel template matching at the rate of 1.6*10/sup 7/ local images per second. >
Stem Cells to Repair the Heart A Clinical Perspective

“It is common sense to take a method and try it: if it fails, admit it frankly and try another. But above all, try something.” — —F.D. Roosevelt The last two decades have witnessed enormous advances in the management of acute myocardial infarction with emphasis upon prompt reperfusion therapy in conjunction with the use of aspirin, β-blockers, angiotensin-converting enzyme inhibitors, and risk factor reduction as cornerstones of postdischarge management. The early and late mortality of myocardial infarction is declining, but, for several reasons, we should not become complacent. Mortality rates from randomized control trials underestimate the community mortality, in that participants in trials are highly selected.1 Moreover, in most countries of the world, many eligible patients do not actually receive reperfusion therapy, or if they do, it is often too late to exert a maximum benefit. Furthermore, the majority of the myocardial infarction population being elderly have a substantial mortality, and comorbidities including diabetes are on the increase. From a clinical standpoint, despite undoubted progress, there remains a large population of survivors of extensive infarctions with diminished cardiac reserve who comprise a reservoir of patients who will develop congestive heart failure with all its grim sequelae.2 The concept that such patients could be treated by myocardial regeneration is logical, tantalizing, and above all, exciting. Moreover, continued progress in the basic sciences has shifted the focus from a concept more closely allied to science fiction to the realm of feasibility. Nonetheless, our expectations need to be tempered by a realistic appreciation of the hurdles to be cleared before we can claim that the new revolution in regenerative biology is truly underway. The recent review in Circulation Research by Orlic et al3 is timely and, as with any good review of a controversial subject, raises many more questions than …
Diabetes Nurse Educators and Preconception Counseling

Purpose: The purpose of this study was to examine the diabetes nurse educator’s role, practice, and training in preconception counseling (PC) when caring for adolescents with diabetes.Methods: A descriptive, correlational research design, using a cross-sectional survey technique, was used. Subjects were 2003 registered nurse members of the American Association of Diabetes Educators. A survey instrument was developed by the investigator and placed on the World Wide Web.Results: Although most of the diabetes nurse educators were aware of PC, most reported not having received any training in PC and would benefit from this education. Thirty percent of the respondents did not routinely provide PC to their adult female clients, and 40% did not provide this to adolescents.Conclusions: Results of this study suggest that the diabetes nurse educators in this sample would benefit from receiving instruction about PC. The diabetes nurse educators should be trained to provide PC to all female clients with diabetes of c...
The 500 kW CW X-band Goldstone Solar System Radar

In recent years the Goldstone Solar System Radar (GSSR) has undergone significant improvements in performance in the areas of increased transmitter power and increased receiver sensitivity. An overview of the radar system and each of these improvements are discussed. The transmitter was upgraded with two new state-of-the-art 250 kW X-band klystrons which increased the radiated power from 360 kW to 460 kW (1.1 dB). The microwave receiver system was improved by cryogenically cooling a major portion of the receive feed components, reducing the receiver noise temperature from 18.0 K to 14.7 K (0.9 dB). Plans for future improvements are discussed. >
‘Hass’ Avocado tree growth on four rootstocks in California. I. Yield and flowering

a b s t r a c t Two experiments were conducted to assess the relationship between alternate bearing, flowering, fruit set, and fruit growth in mature ‘Hass’ avocado (Persea americana Mill.) in Irvine, California. In the first experiment, trees were grown on four clonal rootstocks (‘Thomas’, ‘Topa Topa’, ‘Duke 7’, or ‘D9’), and data collected on yield, number of fruit per tree, average fruit weight, and the timing and duration of flowering over five seasons. In the second experiment, ‘Hass’ trees were grown on ‘Duke 7’ rootstock and data collected on the rate of fruit retention and fruit volume growth over three years. In Experiment 1, the trees exhibited “on” and “off” years in most cropping cycles. Heavy yields were associated with a higher number of fruit per tree, lower average fruit weight, and early and longer periods of flowering. Although yield varied among rootstocks, especially in heavy crop load years, trees growing on different rootstocks had similar cropping patterns. In Experiment 2, fruit abscission varied over years, but rates of volume increase were similar over years. Low yields in ‘Hass’ avocado trees appear to be related to later and shorter flowering periods and fewer and larger fruit at harvest. © 2012 Elsevier B.V. All rights reserved.
A Note on the Leopard‐Skin Chief1

can Anthropologist (1971) will stimulate the reconsideration of the importance of religious as opposed to political forces in the resolution of disputes within acephalous communities. He has attempted to reinterpret Evans-Pritchard's view of the role of the Leopard-Skin Chief among the Nuer. He notes first that political power equals leadership of a coalition. He then cites EvansPritchard's interpretation that the LeopardSkin Chief's power is religious and not political in nature. The import of Greuel's argument is that the Leopard-Skin Chief's actions show elements of both a religious and a political nature, and that in activities leading up to the settlement of disputes the latter is the more important factor. Greuel (1971:1120) then concludes that "EvansPritchard's characterization of the leopardskin chief as a powerless religious figure is inadequate." I would like to discuss Greuel's arguments and then attempt a re-interpretation which reconciles his position with that of the standard ethnographic sources. Greuel's main contention (Ibid.:1118) rests on an interpretation of Howell's conclusion that there "appears to me to be little or no evidence that Leopard-Skin Chiefs had political authority in the past except in so far as they were the centre of prevailing political cohesion" (1954:29). Greuel (1971:1118) takes this to mean that a Leopard-Skin Chief's "opinion carries authority to the extent that he molds and represents a coalition." He further suggests, without citing his source, that in some instances the Leopard-Skin Chief even "leads a coalition made up of the vast majority of the villagers." The core of this coalition is made up of clients and close kin of the Leopard-Skin Chief. The latter, Greuel (Ibid.:1117) suggests, is a strong kin coalition developed and maintained by surpluses received in payment for services rendered by the Leopard-Skin Chief as mediator in disputes. The core is augmented (Ibid.:1119) by more distant kin of the disputants. Greuel (Idem) maintains that "the disputants are prevented from pursuing violent strategies only so long as the leopard-skin chief controls a coalition composed of the vast majority of villagers." The political nature of the Leopard-Skin Chief's activities is seen in that he "prevents the disputants from utilizing certain strategies. . . [and] he has power to influence the members of his coalition through threats of ending his mediation attempts "(Idem). Greuel concludes (Ibid.:1120) that the Leopard-Skin Chief has the ability to rally and maintain these coalitions, and therefore the Leopard-Skin Chief is more than a religious figure lacking in secular political power. Greuel's conclusions would be more con-
The influence of spatial heterogeneity on the behavior and growth of two herbivorous stream insects

Environmental heterogeneity can affect the behavior of organisms, but the consequences of patchiness for organismal energetics (e.g., growth, fitness) are not well understood. This study demonstrates that spatial heterogeneity can affect the growth of aquatic stream insects in laboratory streams, and reveals the behavioral mechanisms for these effects. In a 2×2 factorial design, I experimentally manipulated resource distribution (homogeneous vs. patchy, with the same overall resource levels) and current velocity (fast vs. slow) to investigate the direct and interactive effects of these factors on the drift behavior and growth of two mobile stream grazers, the mayflies Baetis bicaudatis and Epeorus deceptivus. B. bicaudatis nymphs grew larger in environments with homogeneously distributed resources than in patchy environments, and both species grew larger in fast than slow current environments. Patterns of drift behavior over the course of the study corresponded to observed differences in growth. Both species grew to larger body size in treatments where they drifted more successfully among substrates (fast-current treatments) and where they entered the drift less frequently (fast current for both species, and homogeneous treatments for B. bicaudatis). Overall, these results demonstrate that patchiness can significantly influence both the behavior of aquatic insects and the size to which these insects grow. In the light of previously published relationships between nymphal mayfly body mass and fecundity, these results suggest that patchiness in streams may have important consequences for mayfly populations.
Discontinuation of Mycobacterium avium Complex Prophylaxis in Patients with Antiretroviral Therapy–Induced Increases in CD4+ Cell Count: A Randomized, Double-Blind, Placebo-Controlled Trial

Background: Patients infected with HIV who experience increases in CD4 + cell counts are at reduced risk for opportunistic infections. However, the safety of discontinuing prophylaxis against Mycobacterium avium complex has been uncertain. Objective: To compare the rate of M. avium complex infection in patients with increased CD4 + cell counts who receive azithromycin and those receiving placebo. Design: Randomized, double-blind, placebo-controlled trial. Setting: 29 university-based clinical centers in the United States. Participants: 643 HIV-1-infected patients with a previous CD4 + cell count less than 0.05 x 10 9 cells/L and a sustained increase to greater than 0.10 x 10 9 cells/L during antiretroviral therapy. Intervention: Azithromycin, 1200 mg once weekly (n = 321), or matching placebo (n = 322). Measurements: Mycobacterium avium complex cultures, CD4 + cell counts, and clinical evaluations for AIDS-defining illnesses and bacterial infections were done every 8 weeks. Plasma HIV-1 RNA levels were measured at 16-week intervals. Results: During follow-up (median, 16 months), 2 cases of M. avium complex infection were reported among the 321 patients assigned to placebo (incidence rate, 0.5 event per 100 person-years [95% Cl, 0.06 to 1.83 events per 100 person-years]) compared with no cases among the 322 patients assigned to azithromycin (Cl, 0 to 0.92 events per 100 person-years), resulting in a treatment difference of 0.5 event per 100 person-years (Cl, -0.20 to 1.21 events per 100 person-years) for placebo versus azithromycin. Both cases were atypical in that M. avium complex was localized to the vertebral spine. Patients receiving azithromycin were more likely than those receiving placebo to discontinue treatment with the study drug permanently because of adverse events (8% vs. 2%; hazard ratio, 0.24 [Cl, 0.10 to 0.57]). Conclusions: Prophylaxis against Mycobacterium avium complex can safely be withdrawn or withheld in adults with HIV infection who experience increases in CD4 + cell count while receiving antiretroviral therapy.
Dynamic sequencing of test programs

A novel ATE (automatic test equipment) test program development/execution concept employed at Harris is discussed, Test program sets are constructed as a collection of atomic tests (i.e., independent, totally encapsulated tests) whose sequence is determined by a test manager with adaptive reasoning. The tests can be independently constructed and compiled, allowing for more parallel development and reduced maintenance costs. Communication between tests is achieved through a common data storage, and the setup conditions are reconciled by a single setup test module whose actions are directed by a state vector. The test manager employs experiential data to adjust relative failure probabilities in optimally sequencing the atomic tests. >
Competition among Females for Mates in a Species with Male Parental Care, the Midwife Toad Alytes obstetricans

Only males provide parental care in midwife toads (genus Alytes), carrying fertilized eggs entwined around the hind limbs. Although energetic investment in reproduction probably is greater for females, male care may be a limited resource in terms of its quality, and competition among females for access to males might be expected. We videotaped sexual interactions in a group of individuals in the laboratory to determine whether female Alytes obstetricans from Portugal compete for mates. Courtship and mating behavior were largely similar to descriptions of other authors for this species. Males did not exhibit direct aggressive interactions with one another for access to mates. However, females engaged in intense competitive behavior, which included frequent physical displacement of the amplectant male by an unpaired female. One male mated with two females that had competed with one another, suggesting that females may be unable to ensure exclusive access to male parental care.
Effect of Straw Incorporation on 15N‐Labeled Ammonium Nitrogen Uptake and Rice Growth

Abstract A greenhouse experiment was conducted to determine the effect of rice straw residue on growth and uptake of added 15N‐labeled ammonium nitrogen (NH4‐N) (3% 15N abundance at the rate of 150 kg N ha−) by rice in Crowley silt loam soil (Typic Albaqualfs). Higher rates of rice straw addition had an adverse affect on plant growth from the first to sixth week. After 6 weeks, the high rice straw treatment had a positive effect on plant growth (P<0.05). The 15N‐labeled ammonium or fertilizer nitrogen (N) uptake by rice was significantly lower (P<0.05) in the high rice straw treatment as compared to lower rice straw treatments. Greater plant growth was recorded under alternate flooding and draining condition as compared to continuously flooded treatment (P<0.01).
The molecular genomics of metastatic brain tumours.

more effective therapies, and clinicians need predictive laboratory tests to identify patients at risk of developing metastatic brain tumours. The as yet unrealized comprehensive analysis of metastatic brain tumour genomics is necessary to meet these needs. Moreover, without improved understanding of the genomic aberrations that drive metastatic brain tumours, development of biomarkers and molecularly targeted therapies will remain stalled and patient outcomes will continue to be dismal.
In situ hybridization analysis of immunoglobulin heavy chain variable gene expression with family specific oligonucleotide probes.

Abstract We have developed an improved in situ hybridization (ISH) technique for the analysis of human immunoglobulin heavy chain variable ( V H ) gene family expression in suspensions of human B lymphocytes. Oligonucleotide probes specific for framework region (FR) consensus germline sequences for each of the seven human V H gene families were designed and hybridization conditions were developed to accommodate the greatest degree of V H gene variation, maximize the sensitivity of transcript detection, and assure the specificity of the technique. The hybridization parameters were rigorously characterized by Southern hybridization to a panel of 30 V H cDNA clones and by ISH to 17 B cell lines expressing characterized V H genes. Results obtained with ISH using V H gene family and isotype-specific gene probes correlated well with histochemical measures of Ig gene product expression. Profiles of cellular V H gene expression were generated for mitogen stimulated peripheral blood B lymphocytes from six normal subjects. When compared with estimates of frequency of V H genes in the human germline, the results were consistent with a random pattern of V H family utilization.
Specific Testicular Cellular Localization and Hormonal Regulation of the PKIα and PKIβ Isoforms of the Inhibitor Protein of the cAMP-dependent Protein Kinase

We have previously demonstrated that there exist two distinct genes for the thermostable inhibitor protein of the cAMP-dependent protein kinase, PKIalpha and PKIbeta (Van Patten, S. M., Howard, P., Walsh, D. A., and Maurer, R. A. (1992) Mol. Endocrinol. 6, 2114-2122). We have also shown that in the testis, at least eight forms of PKIbeta exist, differing as a result of at least post-translational modification and alternate translational initiation (Kumar, P., Van Patten, S. M., and Walsh, D. A. (1997) J. Biol. Chem. 272, 20011-20020). We now report that in the testis, there is a unique cellular distribution of protein kinase inhibitor forms, with PKIbeta being essentially (if not exclusively) a germ cell protein and PKIalpha being expressed primarily in Sertoli cells. Furthermore, there is a progressive change in the forms of PKIbeta that are present within germ cells with development that is initiated in testis tubules and continues as the germ cells migrate through the epididymis. These conclusions are derived from studies with isolated cell populations and with the at/at germ cell-deficient mouse line, by in situ hybridization, and by following the developmental expression of these proteins in both testis and epididymis. We have also shown that follicle-stimulating hormone (FSH) can increase the expression of both PKIalpha and PKIbeta. The FSH-regulated expression of PKIalpha in the Sertoli cell likely occurs via the normal route of second messenger signal transduction. In contrast, the FSH-dependent PKIbeta expression must arise by some form of Sertoli cell-germ cell intercommunication.
A Longitudinal Model of Continued IS Use: An Integrative View of Four Mechanisms Underlying Postadoption Phenomena

Although initial use is an important indicator of information system (IS) success, it does not necessarily lead to the desired managerial outcome unless the use continues. However, compared with the great amount of work done on IS adoption, little systematic effort has gone into providing insight into continued IS use over time. The objective of this study is to develop a longitudinal model of how users' evaluations and behavior evolve as they gain experience with the information technology application. The proposed model is a unified framework that sheds light on four different mechanisms underlying postadoption phenomena: (1) the processes suggested by the technology acceptance model; (2) sequential updating mechanisms; (3) feedback mechanisms; and (4) repeated behavioral patterns. The proposed model was empirically tested in the context of Web-based IS use in a nonexperimental setting. Our findings suggest that, as hypothesized, each of the four theoretical viewpoints is essential for a deeper understanding of continued IS use. We discuss important findings that emerged from this longitudinal study and suggest directions for additional research.