cssi/SciSciGPT-SciSciNet huggingface dataset:
Reconsidering Internet mobility

Despite the popularity of mobile computing platforms, appropriate system support for mobile operation is lacking in the Internet. The paper argues that this is not for lack of deployment incentives, but because a comprehensive system architecture that efficiently addresses the needs of mobile applications does not exist. We identify five fundamental issues raised by mobility: location, preservation of communication, disconnection handling, hibernation, and reconnection, and suggest design guidelines for a system that attempts to support Internet mobility. In particular, we argue that a good system architecture should: (i) eliminate the dependence of higher protocol layers upon lower-layer identifiers; (ii) work with any application-selected naming scheme; (iii) handle (unexpected) network disconnections in a graceful way, exposing its occurrence to applications; and (iv) provide mobility services at the mobile nodes themselves, rather than via proxies. Motivated by these principles, we propose a session-oriented, end-to-end architecture called Migrate, and briefly examine the set of services it should provide.
Properties of thin film Si-C-N compositions

Thin films of selected amorphous and nano-crystalline compositions from the ternary phase diagram made up of carbon, silicon, and nitrogen, with a significant oxygen impurity, have been grown by chemical plasma reactions, ion beam deposition and plasma CVD. Characterization has focused on optical and mechanical properties to determine the compositions best suited for erosion resistant infrared (IR) optical coatings. The most desirable film compositions for the goal application are located in a compositional region around the C/Si atom ratio = 0.2 and C/N = 0.3. The most durable films have no apparent midwave infrared (IR) absorptions, an optical index of refraction ranging from 2 to 2.1, and indent hardness near 40 GPa. Thin film compositions nearer to carbon nitride show significant midwave absorption bands and lower hardness. Ambient thermal oxidation resistance increases with film nitrogen content, with the most durable films being stable at 700 degree(s)C in air.
IR sensor data fusion for target detection, identification, and tracking

A programmable infrared seeker/data fusion processor has been developed to study the detection, acquisition, and tracking of ship targets in sea clutter. The design requirements are summarized and the design itself is described, including the line scanning seeker, imaging IR seeker, and system computer. The classification algorithm, flyable pod, and operator rack are briefly examined. Results from field exercises and data reduction are summarized.© (1990) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
The inheritance of ascorbic acid content in cabbage.

IN A RECENT paper, Smith and Walker (1946) emphasized the influence of heredity on the ascorbic acid (vitamin C) content of cabbage. Their studies revealed that while environmental factors such as season of growth, time of harvest, and possibly rainfall and amount of sunlight may affect the total amount of this vitamin in cabbage heads, significant differences occur between cabbage varieties and between certain strains or lines within a variety. They found that among the varieties tested, All Head Select usually contained the least amount of the vitamin while Jersey Queen contained the most. A line of Wisconsin All Seasons, derived by a number of generations of close breeding, was discovered to have an unusually high ascorbic acid content. During four consecutive years, repeated analyses of heads from progenies from selfed or sib-crossed individuals showed that the high-vitamin content was relatively stable within this line. F1 hybrids between individual plants from this strain and from low-vitamin strains were reported to have an ascorbic acid content intermediate between the two parents. The purposes of the present work were: (1) to nmake use of the high-vitamin line of cabbage as parental material from which, by hybridization and selection, the factors for high ascorbic acid content could be incorporated into standard commercial varieties; (2) to study the mode of inheritance of factors influencing high production of this vitamin in cabbage. In this paper are included the F1 data from twenty-three crosses and the F2 data from eight of those crosses. Inasmuch as it was not possible to secure complete data from the F3 generation, which admittedly would add much to the genetic interpretation of the inheritance of ascorbic acid content, only the F1 and F2 data are presented in this report. METHODS AND MATERIALS.-The three-slice method of analysis of cabbage heads described by Smith and Walker (1946) was used without modification to determine the ascorbic acid content of all cabbage studied. In 1944, the recommended six-head sample was used to obtain the content of the parent and F1 lines. Since segregating F2 populations were studied in 1945, all available heads were analyzed to determine frequency distributions in the parent lines as well as in the F1 and F2 progenies. With the hope of facilitating future seed production by preserving cabbage heads on the plants, a limited attempt was
Tight versus loose scleral flap closure in trabeculectomy surgery

Thirty-two consecutive trabeculectomy patients were randomized to receive a tight scleral flap closure (15 eyes) with postoperative laser suture lysis, or a loose scleral flap closure (18 eyes) to determine differences in the surgical results. Three months postoperatively no statistical difference in intraocular pressure (loose closure 15.1 ± 3.3 mm Hg, tight closure 15.0 ± 3.6 mm Hg,p > 0.05) or number of glaucoma medicines (loose closure 1.6, tight closure 1.3,p > 0.05) existed between treatment groups. In the early postoperative period, no statistical difference between groups was observed in the anterior chamber depth, visual acuity or intraocular pressure (p > 0.05). Laser suture lysis was performed without complication in nine patients with a statistically significant reduction in intraocular pressure (p < 0.01). This study suggests, by the technique used, that no obvious benefit exists in using a tight versus a loose scleral flap closure when performing a trabeculectomy.
Diurnal patterns of gas‐exchange and metabolic pools in tundra plants during three phases of the arctic growing season

Arctic tundra plant communities are subject to a short growing season that is the primary period in which carbon is sequestered for growth and survival. This period is often characterized by 24-h photoperiods for several months a year. To compensate for the short growing season tundra plants may extend their carbon uptake capacity on a diurnal basis, but whether this is true remains unknown. Here, we examined in situ diurnal patterns of physiological activity and foliar metabolites during the early, mid, and late growing season in seven arctic species under light-saturated conditions. We found clear diurnal patterns in photosynthesis and respiration, with midday peaks and midnight lulls indicative of circadian regulation. Diurnal patterns in foliar metabolite concentrations were less distinct between the species and across seasons, suggesting that metabolic pools are likely governed by proximate external factors. This understanding of diurnal physiology will also enhance the parameterization of process-based models, which will aid in better predicting future carbon dynamics for the tundra. This becomes even more critical considering the rapid changes that are occurring circumpolarly that are altering plant community structure, function, and ultimately regional and global carbon budgets.
The dynamic redeployment coverage location model

Demand for ambulances is known to fluctuate spatially and temporally by day of the week and time of day. Faced with fluctuating demand during the day, emergency medical systems (EMS) managers utilize redeployment strategies to meet demand. Such shifting of personnel, although better able to cover a region with fluctuating demand, can cause fatigue amongst ambulance crew members. Considering these phenomena, we extend the dynamic available coverage location model to be driven by two objectives: (1) Minimize the number of ambulances, and (2) Minimize the number of redeployments for a given fleet during a given shift. We develop a heuristic search algorithm and present the comparative statistics using real data from an urban EMS agency. Our findings suggest that EMS managers can effectively balance a need for additional ambulances with those redeployments required to meet variable demand patterns.
Attributions and depression: why is the literature so inconsistent?

A large body of literature examining the relations between depression and causal attributions has produced inconsistent findings. Many studies have clearly had inadequate statistical power, however, so that negative findings cannot be readily interpreted. In this review, statistical power was computed for all published analyses relating depression to attributions to any of the following: internal, stable, or global causes, or their composite, ability/character, effort/behavior, luck, or task difficulty. On average, the power of these analyses was very poor. For example, only 8 of the 87 analyses had a probability of .80 or better of detecting a small-medium true population effect (e.g., r = .20). Separating studies by levels of power helped to clarify the inconsistencies in the literature. Whereas across all published studies depression was fairly consistently related only to the composite of internal, stable, and global attributions, those few studies with fairly high power all reported significant relations of depression to stable and global attributions as well as to the composite. It is suggested that increased attention be paid to the power of statistical analyses in planning studies and in drawing conclusions from completed studies.
Mathematical model for kinetics of alkali-silica reaction in concrete

Vast though the literature on the chemistry of the alkali ‐ silica reaction (ASR) in concrete has become, a comprehensive mathematical model allowing quantitative predictions seems lacking. The present study attempts a step toward this goal. While two distinct problems must be dealt with, namely, (1) the kinetics of the chemical reaction with the associated diffusion processes and (2) fracture mechanics of the damage process, only the former is addressed here. The analysis is focused on the recent attempts by C. Meyers and W. Jin to incorporate ground waste glass (mainly, bottle glass) into concrete. With minor adjustments, though, the model can be applied to ASR in natural aggregates as well. A characteristic unit cubic cell of concrete containing one spherical glass particle is analyzed. A spherical layer of basic ASR gel grows radially inward into the particle, controlled by diffusion of water toward the reaction front. Modification of the solution for the case of mineral aggregates with veins of silica is also indicated. Imbibition of additional water from the adjacent capillary pores, which causes swelling of the gel, is described as a second diffusion process, limited by the development of pressure due to resistance of concrete to expansion. The water used up to form the basic ASR gel and imbibed to cause its swelling appears as a sink term in the non-linear diffusion equation for the global water transport through a concrete structure. The differential equations are integrated numerically. The study of the effects of various parameters provides improved understanding of the ASR, and especially the effect of glass particle size. Full prediction will require measurements of some parameters of the reaction processes. D 2000 Elsevier Science Inc. All rights reserved.
Elementary School Teachers' Perspectives on Health Instruction: A Commentary

(2002). Elementary School Teachers' Perspectives on Health Instruction: A Commentary. American Journal of Health Education: Vol. 33, No. 2, pp. 83-87.
Effect of calcium channel antagonists on the cardiac vagal tone response to submaximal exercise

Reductions in cardiac vagal tone have been shown to correlate with a greater susceptibility to ventricular fibrillation. Calcium antagonists have been shown to protect against malignant arrhythmias probably as the result of direct actions on cardiac muscle. However, these drugs could also reflexively alter cardiac vagal tone as a consequence of reductions in arterial pressure. Therefore, the effects of various calcium channel antagonists on cardiac vagal tone, both at rest and during exercise, were investigated. The R-R interval was recorded in chronically instrumented mongrel dogs (n = 39) and the amplitude of the respiratory sinus arrhythmia (0.24–1.04 Hz) was calculated using time-series analysis techniques. Before exercise, verapamil (n = 17, 250 μg/kg), nifedipine (n = 5, 10 μg/kg; n = 9, 100 μg/kg), diltiazem (n = 10, 100 mg/kg), Ro 40-5967 (n = 14, 1,000 μg/kg), and magnesium sulfate (n = 10, 100 mg/kg) significantly increased heart rate, while flunarizine (n = 11, 2.5 mg/kg) and a lower dose of Ro 40-5967 (n = 5, 250 μg/kg) did not affect heart rate. During exercise, nifedipine (high dose) increased heart rate, while Ro 40-5967 (high dose) decreased heart rate. All six drugs reduced vagal tone before exercise; magnesium and nifedipine (high dose) elicited the greatest reduction, while flunarizine produced the smallest decrease. The vagal tone response to exercise was not affected by flunarizine and Ro 40-5967 (low dose), but it was accentuated by magnesium, nifedipine, and verapamil. Intermediate responses were noted for Ro-40-5967 (high dose) and diltiazem. Pronounced hemodynamic effects were noted for flunarizine, magnesium, nifedipine, and verapamil, but not for Ro 40-5967. Thus, calcium antagonists have variable hemodynamic profiles and can elicit pronounced reductions in cardiac vagal tone, presumably due to activation of the baroreceptor reflex. © 1992 Wiley-Liss, Inc.
Cortical resection for epilepsy in children with linear sebaceous nevus syndrome.

Linear sebaceous nevus syndrome (LSNS) is a rare neurocutaneous syndrome that is associated with seizures and mental retardation. The cortical abnormalities that are associated with this syndrome include focal cortical dysplasia, partial hemimegalencephaly and holohemispheric hemimegalencephaly. Few reports have addressed the utility of cortical resections for epilepsy treatment in the setting of LSNS. We report 3 children with this syndrome who underwent extensive cortical resections and experienced significant improvement in seizure frequency. Our results support the utility of extensive cortical resections for children with this condition.
Cs-Based Frequency Measurement of a Single, Trapped Ion Transition in the Visible Region of the Spectrum

An optical frequency chain referenced to a Cs atomic clock has been used to measure directly the frequency of the electric quadrupole allowed $5s^{2}S_{1/2}\ensuremath{-}4d^{2}D_{5/2}$ transition at 445 THz in a single, trapped, and laser cooled ${}^{88}{\mathrm{Sr}}^{+}$ ion. A transition frequency, ${f}_{S\ensuremath{-}D}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}444779044095.4\mathrm{kHz}$ with an estimated standard uncertainty of 0.2 kHz has been determined. Intrinsic offsets of the probed ion transition in the current experiment are calculated to be at the ${10}^{\ensuremath{-}15}$ level.
‘Land-marks of the universe’: John Herschel against the background of positional astronomy

SummaryJohn Herschel (1792–1871) was the leading British natural philosopher of the nineteenth century, widely known and regarded for his work in philosophy, optics and chemistry as well as his important research and popular publications on astronomy. To date, however, there exists no extended treatment of his astronomical career. This paper, part of a larger study exploring Herschel's contributions to astronomy, examines his work in the context of positional astronomy, the dominant form of astronomical practice throughout his lifetime. Herschel, who did not himself practice positional astronomy and who was known for his non-meridional observations of specific stellar objects, was nonetheless a strong advocate for positional astronomy—but for very different reasons than the terrestrial applications to which it was most often put. For Herschel, the star catalogues of positional astronomy were the necessary observational foundation upon which information about the stars as physical objects could be construc...
Impact of Nutrition and Obesity on Chronic Liver Disease

Undernutrition and obesity are at opposite ends of a spectrum that has an enormous impact on all aspects of liver diseases. The myriad effects of the opposing ends of the nutrition spectrum have led to a wealth of research aimed at elucidating the exact mechanisms of how they cause liver damage. In this article, the role of the liver in nutrient and energy metabolism is discussed, as well as the known and possible effects of specific nutrient deficiencies and obesity.
Visual servoing frameworks for microassembly of hybrid MEMS

In this paper we present a novel visual servoing framework for assembly of hybrid microelectromechanical systems (MEMS). The framework incorporates a supervisory logic-based controller that allows the use of multiple visual sensors in order to execute an assembly task. The introduction of multiple visual sensor arrays allows motion of microassembly tasks to initially be controlled `globally' and then locally using a `high precision' view. We use the technique of depth-from-focus to visually servo along the optical axis. This gives us the ability to perform full 3D micropositioning under visual control. The supervisory logic-based controller selects the relevant sensor to be used at a particular stage in the assembly process, which allows us to take full advantage of the individual sensor's attributes such as field-of-view and resolution. The combination of robust visual tracking and depth estimation within a supervisory control architecture is used to perform high-speed, automatic micro-insertions. We present results for the micro insertion task performed under this framework to demonstrate it's feasibility in assembly of MEMS.© (1998) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Real time endoscopic imaging of oxyradical generation in pig stomach during ischemia-reperfusion.

Abstract Background. Oxygen-free radicals generation is considered to be a major cause of gastric injury during reperfusion. Chemiluminescence has been used to assess real-time free radical release on the surface of isolated organs. Aims. To evaluate the combined use of chemiluminescence and gastroendoscopy techniques and to assess the real-time production of free radicals during ischemic damage of the gastric wall in an animal model. Patients and methods. For the experiment, an optical junction was set up between a fibroendoscope and a luminograph apparatus. Three pigs were submitted to gastrofibroendoscopy before, during and after 30 min of clamping of the coeliac artery. Under basal conditions, at the end of the ischemic phase and at the beginning of reperfusion, 1 mM of lucigenin, a specific superoxide enhancer, was injected in the left gastric artery of the animal. The endoscopic live images and chemiluminescence emission were recorded and successively superimposed to measure rate and spatial distribution of photon emission (photons/s). Results. Free radical production was not observed under basal conditions or during the ischemic phase, but significantly increased during reperfusion reaching a maximum peak after 15 min (0.6±0.2 photons×10 5 /s) and decreased progressively thereafter. The superimposition of live and chemiluminescence images allowed the determination of the regional production rate and distribution of photons. Conclusions. Preliminary observations, in an animal model, on an innovative imaging system which allows the visualization of rate and spatial distribution of reactive oxygen species formation are presented. This new endoscopic technique could be useful for the assessment of oxidative gastric mucosal injury in several gastric diseases; however, further studies remain necessary to determine the applicability of this technique in humans.
Some Frequentist Properties of a Bayesian Method in Clinical Trials

Interim analysis in clinical trials involving two treatments are commonplace nowadays. Concerns from different points of view are widely seen in the literature. With a Bayesian approach there is no consideration of type I error and no power calculation. In contrast, there is no difficulty or arbitrariness in picking a prior distribution with a classical approach. In this paper, however, a stopping rule based on the Bayesian approach is discussed from a classical point of view. In specific, we consider application to normal sampling analyzed in stages and demonstrate the role of the prior distributions. In the first part of the paper, we define the stopping rules based on the posterior probabilities. We then develop the stopping boundaries in explicit forms, which can be easily computed with a hand calculator and a standard normal probability distribution table. We also summarize the frequency characteristics of this stopping rule into several results. The major question that is addressed in the second part of the paper is: how will a prior affect the results of a clinical trial study based on the posterior probabilities? The criteria for assessment will be strictly of a Neyman-Pearson kind. We use N(v, τ2) as the prior distribution for the difference between treatments, δ. We show that the test is unbiased if v = 0 or τ = ∞. In addition, some rather obvious facts are again summarized into a couple of results. We also discuss, with a table and a figure, the power functions of non-trivial cases with extreme v and τ using a numerical example.
Two Morphologically and Kinetically Distinct Populations of Lymphoid Cells in the Bone Marrow

LYMPHOID cells account for 20–30 per cent of all nucleated cells in the bone marrow of common laboratory animals and in the human foetus. Evidence from a number of sources suggests that bone marrow lymphocytes may be functionally distinct from lymphocytes of lymph and lymphoid tissue in spite of morphological similarities1. Lymphoid cells of the bone marrow comprise a heterogeneous population consisting of pachychromatic small lymphocytes which do not synthesize DNA and of leptochromatic transitional cells which synthesize DNA and divide2. On the basis of differences in cytoplasmic basophilia, transitional cells themselves have been further subdivided3. It was shown that pale and basophilic transitional cells incorporated 3H-thymidine at markedly different rates after pulse label4. This observation suggested that transitional cells with basophilic or pale cytoplasm may represent cell populations with different kinetic behaviour. I report here preliminary experiments to characterize the cell cycle and estimate the rate of renewal for these cells.
AFRICAN NON-BREEDING AREAS OF FENNOSCANDIAN OSPREYS PANDION HALIAETUS: A RING RECOVERY ANALYSIS

SUMMARY Saurola, P. 1994. African non-breeding areas of Fennoscandian Ospreys Pandion haliaetus: a ring recovery analysis. Ostrich 65:127-136. More than 36 000 Ospreys have been ringed in Fennoscandia up to 1992 and 638 of these have been reported from 30 different African countries. The recoveries suggest that adult and first-year Ospreys arrive in Northern Africa from earl September and cross the Sahara in late September to October. A record bird migrated 9817 km from Finland to South Africa in less than 40 days, at an average speed of more than 245 km/day. The majority of all age classes of Fennoscandian Ospreys spend December to February in equatorial Africa. The average compass heading from the different parts of the Fennoscandian breeding areas to the sub-Saharan non-breeding areas is roughly the same, ca. 206°. The longitude of the non-breeding area is dependent on the longitude of the breeding area. Western subpopulations spend their non-breeding period further to the west than more eastern subpop...
On the Absolute Difference Chains

Let F(x), F ( 0 ) = 0 , be a fixed probability distribution function on R § with measure F(dx), and let X 1, X 2 .. . . be a sequence of independent and identically distributed random variables with distribution F. For any random variable Z > 0 , independent of X1, X 2 . . . . . we define Y(0, Z)=Z, and inductively on n>0 , Y(n + 1, Z) = I Y(n, Z) X, + 1 lIf F z denotes the distribution of Z, then Y(n, Z) is a realization of a homogeneous Markov chain with initial distribution F z. We will call this the "absolute F-chain with initial distribution Fz," but if P { Z = x } = 1 for some x > 0, then we write Y(n, x) in place of Y(n, Z). The present paper is devoted to tying up some loose ends in connection with the following remarkable result of W. Feller [I, VI, 11, Example (t)]: if 0 O }. But in this latter case (for #<oo) the invariant probability is never unique, and we exhibit another invariant probability which is supported by the same lattice as F(dx). We remark only briefly on the question of when this last is unique among probabilities on the lattice, this being a question about integer-valued Markov chains for which general uniqueness theorems are well known. Finally, we obtain a new proof of the following characterization of the exponential and mixed geometric distributions, obtained by Ibragimov, Lindtrop, and Vallander [3] (without use of the present absolute F-chain context).
Developmental decline in components of signal transduction pathways regulating protein synthesis in pig muscle

Our previous studies showed that the feeding-induced stimulation of protein synthesis in skeletal muscle of neonatal pigs is accompanied by enhanced phosphorylation of the eukaryotic initiation factor (eIF)4E-binding protein (4E-BP1) and the ribosomal protein S6 kinase (S6K1). These effects of feeding are substantially reduced with development. The goal of the present investigation was to delineate the basis for the reduced responsiveness to feeding observed in the older animals. In these studies, the content and activity of protein kinases located upstream of S6K1 and 4E-BP1 in signal transduction pathways activated by amino acids, insulin, and insulin-like growth factor I were examined in 7- and 26-day-old pigs that were either fasted overnight or fed porcine milk after an overnight fast. Feeding stimulated phosphatidylinositol (PI) 3-kinase activity to the same extent in muscle of 7- and 26-day-old pigs, suggesting that PI 3-kinase is not limiting in muscle of older animals. In contrast, protein kinase B (PKB) activity was significantly less in muscle from 26- vs. 7-day-old pigs, regardless of nutritional status, suggesting that its activity is regulated by mechanisms distinct from PI 3-kinase. In part, the reduced PKB responsiveness can be attributed to a developmental decline in PKB content. Likewise, muscle content of the protein kinase termed mammalian target of rapamycin (mTOR) in 26-day-old pigs was <25% of that in 7-day-old animals. Finally, in agreement with our earlier work showing that S6K1 phosphorylation is reduced in older animals, S6K1 activity was stimulated to a lesser extent in 26- compared with 7-day-old pigs. Overall, the results suggest that the blunted protein synthetic response observed in 26- vs. 7-day-old neonatal pigs is due in part to decreased content and/or activity of signaling components downstream of PI 3-kinase, e.g., PKB, mTOR, and S6K1.
Controlling dynamic stereoisomerism in transition-metal folded baskets

We synthesized chiral molecular baskets (R3/S3)-1, containing three pyridine rings at the rim of a bowl-shaped platform. Each pyridine was tethered to the platform via a CH(CH)3 stereogenic center. In line with prior studies, we found that chiral basket (R3)-1 would coordinate to Ag(I) cation forming a Ag(I)–(R3)-1 complex (ΔG° = −5.9 kcal mol−1 at 298.0 K). Furthermore, we used spectroscopic methods (1H NMR, UV-Vis and CD) to establish that the CH(CH)3 stereogenic center with R configuration in Ag(I)–(R3)-1 would direct the twisting of the pyridine rings at the rim in a clockwise orientation (P configuration). UV-Vis and CD spectra of Ag(I)–(R3)-1(P) were also computed (TD-DFT; BHLYP/SV(P),TZVP), showing good agreement with the experimental data. Controlling dynamic stereoisomerism in basket-like systems is important and the results of this study will be useful for examining the relationship between chiral recognition and reactivity in gated and confined environments.
Metastatic hepatocellular carcinoma to the heart

Right ventricular heart involvement of an otherwise unknown hepatocellular carcinoma is presented and the cytologic differential diagnosis is discussed. This tumor displays classic cytologic features of hepatocellular carcinoma, including trabecular arrangements with prominent endothelial cells and numerous intracytoplasmic hyaline bodies. The background contains many “naked nuclei” and extracellular hyaline bodies. The patient is alive with residual disease 4 months after surgical extirpation of the cardiac mass. Diagn. Cytopathol. 2000; 23:406–408. © 2000 Wiley-Liss, Inc.
A New Microsporangial Protostelid, Microglomus paxillus gen. and sp. nov.*

SYNOPSIS. Microglomus paxillus is described as a new genus and species of the subclass Protosteliida (Class Eumyceto-zoa). It has been isolated only once from casuarina bark collected in Oahu, Hawaii. The new organism is characterized by a uninucleate ameboid trophic stage that feeds on bacteria and by sporocarps with spike-like stalks terminated by microspo-rangia containing tetrads of ameboid protoplasts or thin-walled spores. No flagellate cells are produced. The tetrads are typically formed by successive bipartition following conjugate nuclear divisions in the sporogen. The cells of the tetrad are at first binucleate but soon become uninucleate as a result of nuclear degeneration. Variations in the process of sporogenesis are described.
Analysis of antigen uptake and presentation by Epstein-Barr virus-transformed human lymphoblastoid B cells.

Epstein-Barr virus-transformed human B cells (EBV-B cells), but not resting B cells or B cells activated by T cell-derived factors, have been shown to support the proliferation of tetanus toxoid (TT)-specific autologous T cell clones in response to TT antigen. The accessory cell function of EBV-B cells was compared to that of monocytes with regard to antigen uptake and processing. After an 18-h incubation period with 125I-labeled TT, the amount of radioactivity associated with the cells (approximately 50 ng/10(7) cells) and the percentage of cells containing radiolabeled material (approximately 50%) were equivalent for EBV-B cells and monocytes. Like with monocytes, EBV-B cells pulsed with TT for 18 h or more were equivalent in their capacity to induce T cell proliferation to EBV-B cells to which soluble TT was added for the duration of the culture period. The requirements for antigen uptake and presentation to T cells were similar for both EBV-B cells and monocytes. Both processes were energy dependent, inhibited by cold (4 degrees C), 2-deoxyglucose, and azide, and both required no de novo protein synthesis as they were not affected by pretreatment of the cells with the irreversible protein inhibitor pactamycin . Trypsin treatment of antigen-pulsed EBV-B cells and monocytes followed by fixation for 1 min in 0.03% paraformaldehyde completely abolished the capacity of both cell types to induce T cell proliferation. In both EBV-B cells and monocytes, antigen presentation, but not antigen uptake, was inhibited by the addition of the lysosomotropic agent chloroquine during the antigen-pulse period suggesting that the mechanisms of antigen processing are similar for both cell types. Vacuoles positive for acid phosphatase with an electron microscopic structure similar to that of lysosomes were found in EBV-B cells but not in resting B cells or B cells activated by T cell-derived factors. The present observations indicate that EBV-B cells take up antigen and process it in a fashion similar to monocytes. The presence of lysosomes appears to correlate with the capacity of B cells to present antigen.
The interaction of student and program variables for the purpose of developing a model for predicting graduation from graduate programs over a 10-year period

The purpose of this study was to investigate whether there is some factor or set of factors which will predict the probability of graduation from doctoral programs. This study concentrated on two areas: (a) the factors available to the selection committee when the students apply for admission into graduate programs, and (b) those factors emerging after admission, resulting from the students' meeting program-imposed requirements for graduation. Data were collected from the file of each student admitted to the doctoral program in Educational Administration. The results of the study indicated that program variables are more important than admission variables in predicting graduation. and the technique of Path Analysis is highly recommended to study the problem of student progression through graduate departments.
De novo synthesis and hormonal regulation of a dipeptidase in Cucurbita maxima

Abstract The following evidence was obtained for the de novo synthesis of dipeptidase in squash ( Cucurbita maxima Duch. var. Hubbard) cotyledons during germination: (i) the amount of [ 14 C]leucine incorporated into the dipeptidase was greater than that found in other proteins; (ii) the enzyme coincided with a peak of radioactivity in DEAE column chromatography; and (iii) the specific radioactivity of the enzyme increased with purification. There was also a positive correlation between the rate of [ 14 C]leucine incorporation into dipeptidase and the rate of dipeptidase development. Four plant growth regulators, gibberellic acid (GA) benzyladenine (BA), indol-3-acetic acid (IAA), and abscisic acid (ABA) were examined for their effect on the development of dipeptidase activity at 5 × 10 −6 and 5 × 10 −5 M. None of these regulators affected the activity of the isolated dipeptidase per se . In intact see ds, BA and IAA inhibited the development of dipeptidase activity at the higher concentration, ABA reduced the activity at both concentrations; however, GA enhanced its development at the higher concentration. In distal-half cotyledons, BA and GA stimulated enzyme development but they showed no synergistic effect. IAA suppressed the development of enzyme activity at the higher concentration and ABA inhibited development at both levels.
A study of the single polypeptide nature of rhodanese. A comparison of different preparations.

Abstract The enzyme rhodanese (EC 2.8.1.1) appears as a single polypeptide chain protein on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The molecular weight of this species is approx. 33 000. This contrasts with previous reports that rhodanese behaves on gel filtration chromatography as a rapidly equilibrating monomer-dimer system composed of identical subunits with a molecular weight of 18 500. We have investigated this apparent discrepancy by isolating the enzyme by the two different preparative procedures used in the above investigations. The two cyrstalline samples were subjected to gel filtration chromatography under a wide variety of conditions and to sodium dodecyl sulfate disc gel electrophoresis. The two preparation yielded rhodanese which behaved identically and no evidence for the monomeric species was obtained under any experimental condition tested. Thin-layer gel chromatography of clarified liver homogenates gave no evidence of rhodanese species other than that present in the purified samples. The variation in molecular weights observed in gel filtration chromatography may be a reflection of the conformational mobility of the enzyme leading to solvent-dependent changes in Stokes radisu. If rhodanese is dimeric, special interactions must stabilize it under the conditions tested here.
Evil and the many universes response

I formulate and defend a version of the many universes (or multiverse) reply to the atheistic argument from evil. Specifically, I argue that (i) if we know that any argument from evil (be it a logical or evidential argument) is sound, then we know that God would be (or at least probably would be) unjustified in actualizing our universe. I then argue that (ii) there might be a multiverse and (iii) if so, then we do not know that God would be (or at least probably would be) unjustified in actualizing our universe. It follows that we cannot know that the atheistic argument from evil is sound, in which case we cannot be certain that the argument succeeds, and so it is rational to refuse to reject theism because of such arguments.
Star Formation in Clusters: Early Subclustering in the Serpens Core

We present high-resolution interferometric and single-dish observations of molecular gas in the Serpens cluster-forming core. Star formation does not appear to be homogeneous throughout the core, but is localized in spatially and kinematically separated subclusters. The stellar (or protostellar) density in each of the subclusters is much higher than the mean for the entire Serpens cluster. This is the first observational evidence for the hierarchical fragmentation of protocluster cores suggested by cluster formation models.
Leading Psychology Forward: Staying the Course in Uncertain Times.

Like everyone in the country, those in organized psychology have functioned recently in a climate marked by threats of terrorism, uncertainty, and a declining economy. In such challenging times, it might seem logical for the profession to wonder how it needs to change to respond to current circumstances. Yet at such times, staying the course already charted is likely a far more effective strategy. For psychology, this means continuing to press for mental health parity, educating decision makers about the important role of psychological services in preventive care, helping to integrate psychological and physical health services, continuing to hold managed care companies accountable, and increasing the profession's political giving. Psychologists must also be prepared to ensure that psychological services are treated as an integral part of any health reform plan that emerges.
Studies of clean metal surface relaxation experiment-theory discrepancies

A series of Low-Energy Electron Diffraction Intensity vs. Voltage (LEED I–V) measurements for Rh(001), W(110) and Ti(0001) have been undertaken in order to help resolve discrepancies between experiment and theory for the surface relaxations of certain transition metals. LEED measurements and analysis indicate the following results for the change of first (d12) and second (d23) interlayer spacings, relative to the bulk interlayer spacing d0: for Rh(001), Δ d12/d0=-1.4± 1.4% and Δ d23/d0=-0.6± 1.4%; for W(110), Δ d12/d0=-3.0± 1.3% and Δ d23/d0=+0.2± 1.3%; and for Ti(0001), Δ d12/d0=-4.9± 1.0% and Δ d23/d0=+1.4± 1.0%. In each case, the new measurements help to resolve the experiment–theory surface relaxation discrepancies. In addition, two of these surfaces [W(110) and Ti(0001)] show substantial contractions in the first interlayer spacing, d12. Large relaxations for close-packed surfaces lend support to the promotion–hybridization picture of surface relaxation put forth recently by P. J. Feibelman [P. J. Fe...
The changing meanings of "mutation:" A contextualized study of public discourse.

A quantitative examination of a representative sample of popular discourse about genetics and heredity from U.S. mass magazines between 1919 and 1996 indicates that the term "mutation" has become increasingly negative in its connotations through time. Although it has been used more frequently than alternative terms such as "variation" and "alteration," it is more likely to bear negative connotations than these alternatives. Increases in the negative contextualization of "mutation" were initially associated with reports of genetic damage to humans from nuclear radiation after 1956. Later increases in negative connotations appear to arise from more diffuse sources. These results are contextualized by comparison to other research on meanings of mutation and an observational sample of scientific discourse.
Electrodeposition of Ba.6K.4BiO3

Abstract A novel, low temperature molten salt electrochemical technique has been used for the preparation of Ba.6K.4BiO3. The resulting crystalline material has been characterized by X-Ray diffraction, scanning electron microscopy and by energy dispersive X-ray analysis.
Pacific and Atlantic sea surface temperature influences on streamflow in the Apalachicola–Chattahoochee–Flint river basin

Large scale climate phenomena can provide valuable information for regional climate and streamflow in many parts of the world. Several climate phenomena may impact a given area and their value for providing information on streamflow is dependent on first establishing the local relationship. This study was conducted to establish the individual and coupled impacts of the El Nino–Southern Oscillation (ENSO), Pacific Decadal Oscillation (PDO), and Atlantic Multidecadal Oscillation (AMO) on streamflow in the Apalachicola–Chattahoochee–Flint (ACF) river basin. Differences in annual and seasonal streamflow using two unimpaired streamflow datasets based on the phase(s) of ENSO, the PDO, and the AMO were evaluated using the nonparametric rank-sum test. Few statistical differences were found for the individual impacts of ENSO and the PDO on annual and seasonal streamflow; differences based on ENSO were largely confined to the southern portion of the basin. Significant differences in annual streamflow based on the AMO were largely confined to the northern half of the basin. Differences in seasonal streamflow based on the AMO were found for much of the year in the northern portion of the basin but were confined to the winter season in the southern portion. Significant differences in annual and seasonal streamflow were found between the La Nina/positive AMO phase and the El Nino/negative AMO phase, between the positive AMO/negative PDO phase and the negative AMO/negative PDO phase, and there appears to be a modulation of the impacts of La Nina by the phase of the AMO. A greater number of stations and a greater magnitude of significant differences were found for the coupled impacts than for the individual impacts of ENSO, the PDO, and the AMO; indicating the importance of the coupled impacts on regional streamflow when establishing the role of annual, decadal, and multidecadal climate variability.
Chronobiology of parturients receiving neuraxial labour analgesia with ropivacaine and fentanyl: a prospective cohort study.

Abstract Background The circadian variation in biologic rhythm has been known to affect labour pain. The duration of action of ropivacaine or fentanyl used in treatment of labour pain has been demonstrated to vary with different times of the day. The aim of this study is to find whether the need for epidural supplementation for breakthrough pain is significantly affected by the time of day, in patients who are on a continuous epidural infusion of these drugs. Methods In this prospective cohort study, parturients with spontaneous onset of labour were given a combined spinal-epidural technique with spinal ropivacaine 2mg+fentanyl 15μg followed by an epidural infusion of ropivacaine 0.1–0.125% with fentanyl 2μg/mL at 10mL/hour. A total of 1657 patients were divided into four groups: (1) morning: analgesia request: 7:01 to 13:00, delivery before 19:00; (2) afternoon: analgesia request: 13:01 to 19:00, delivery before 1:00; (3) evening: analgesia request: 19:01 to 1:00, delivery before 7:00 and (4) night: analgesia request: 1:00 to 7:00, delivery before 13:00. Pain scores before epidural analgesia, need for additional epidural supplementation, side effects and patient satisfaction scores were compared between the groups. Results The pain scores before epidural analgesia were significantly higher in evening and night groups than in morning and afternoon groups (6.95±2.4, 7.38±2.2 compared to 6.67±2.5, 6.49±2.7 respectively, P 0.001). Incidence of breakthrough pain, side effects and parturient satisfaction scores were not significantly different between groups. Conclusion Parturients with labour onset and neuraxial analgesia request in the evening and night experienced higher pain scores. However, no significant differences in the incidence of breakthrough pain or the quality of analgesia were observed with the provision of commonly used concentrations of ropivacaine with fentanyl via continuous epidural infusion.
Stream Order and Order Statistics: Quantile Estimation in Random-Order Streams

When trying to process a data stream in small space, how important is the order in which the data arrive? Are there problems that are unsolvable when the ordering is worst case, but that can be sol...
Intermediates of the aerobic dissimilation of 2-ketogluconate by Pseudomonas aeruginosa.

Abstract A number of compounds have been detected chromatographically from the oxidation of labeled 2-ketogluconate by P. aeruginosa. These compounds are: arginine; alanine; lysine; a leucine; histidine; cysteine; glutamic acid; lactic, citric, succinic, fumaric, malic, α-ketoglutaric, pyruvic, and malonic acids; dihydroxyacetone; a nucleic acid; and glucose phosphate. The presence of a tricarboxylic acid cycle is indicated.
Cloning and functional analysis of an extrachromosomally amplified multidrug resistance-like gene in Leishmania enriettii.

Abstract The goal of this work was to investigate the mechanism of drug resistance in Leishmania enriettii as a model system for drug resistance both in human leishmaniasis and on other parasitic diseases. Parasites were selected in increasing concentrations of vinblastine, an inhibitor of microtubule assembly, and resistant clones were isolated which grew in concentrations 5–30 times the IC 50 (30 μg mg ml −1 ) of parental cells. The vinblastine-resistant parasites were also resistant to promycin, an unrelated drug which inhibits protein synthesis. This cross-resistance to unrelated drugs had previously been observed in mammalian cells and recently in L. donovani . The proposed mechanism for this cross-resistance is drug effiux mediated by increased expression of a P-glycoprotein molecule encoded by a multidrug resistance ( mdr ) gene. Here we report the identification, cloning and sequencing of an mdr -like gene from L. enriettii, lemdrl , and demonstrate that this gene is amplified on an extrachromosomal circle of 35–40 kb in vinblastine-resistant L. enriettii . The longest open reading frame in the cloned gene is 1280 amino acids with a predicted protein of 140 kDa. The predicted protein has a structure similar to that for all other reported P-glycoproteins namely 12 transmembrane domains and 2 ATP binding sites, arranged in 2 similar half-molecules. Comparison of the primary amino acid sequence with other known mdr gene products demonstrates a significant homology with 37% amino acid identity with human mdr 1 and 83% identity with the L. donovani 1mdr 1 gene. The lemdr 1 gene was cloned in the expression vector pALTNEO and transfected into wild-type L. enriettii and the resulting transfected cells were resistant to vinblastine but at lower levels than in the selected mutant cells.