cssi/SciSciGPT-SciSciNet huggingface dataset:
Parallel Communication With Limited Buffers

Currently known parallel communication schemes allow n nodes interconnected by arcs (in such a way that each node meets only a fixed number of arcs) to transmit n packets according to an arbitrary permutation in such a way that (1) only one packet is sent over a given arc at any step, (2) at most 0(log n) packets reside at a given node at any time and (3) with high probability, each packet arrives at its destination within 0(log n) steps. We present and analyze a new parallel communication scheme that ensures that at most a fixed number of packets reside at a given node at any time.
Electoral Cycles in Crime in a Developing Country: Evidence from the Indian States

Using annual data on the major Indian states, I investigate whether the timing of elections affect the crime rate or not. Consistent with the idea that an incumbent politician might exert greater effort in an election year to improve the law and order situation, I find that scheduled elections are associated with a fall in crime. Both property crimes and violent crimes decline in an election year, with the fall in property crimes being statistically significant. Using an instrumental electoral cycle I also find that both categories of crime are responsive to the proximity to an election year - going up in the initial years of an incumbent's tenure, and declining in the later periods, as elections draw nearer. These results suggest that elections can generate crime cycles in a developing country, and also point towards the need for greater transparency and accountability in political governance.
Customer Relationship Management: A Combined Aproach by Customer Segmentation and Database Marketing

The Customer Relationship Management is supported by efficient database marketing systems to assign the best offers to the appropriate customers. The success of direct marketing campaigns is directly related to the degree to which the campaign reaches its target group. Therefore the selection e.g. of the correct addressees of a mailing is a crucial step that already determines its outcome. However, the selection process is very complex and hardly automated even today. One of the important goals is to increase response rates in direct marketing. Based on data of customer profiles a response model is set up and it is then applied to select potential buyers of certain products for future mailings or telephone sales campaigns. In this paper a fuzzy clustering algorithm for customer segmentation of a financial institute is described. Based on these results, a decision tree model is used for database marketing of direct marketing products. The tasks of the data mining process from the conceptual design to the integrated business intelligence solution will be explained using a problem solving process model.
An update on the biomedical prospects of marine-derived small molecules with fascinating atom and stereochemical diversity.

In this chapter we discuss a selection of structurally diverse marine-derived small molecules (MDSMs) with potent and/or specific bioactivity and analyze their biomedical applications. The compounds included have been isolated either from marine macroorganisms, including sponges, ascidians (tunicates), bryozoans, and molluscs, or from microorganisms, such as bacteria and fungi. Our inquiry begins with a look back in time at a selection of important marine natural products, with particular focus on compounds in the clinical pipeline. The chapter continues with an analysis of a biosynthetically diverse assortment of 22 MDSMs and their structural elements of atom and stereochemical diversity. Entries have been divided into five biosynthetic classes: terpene, polyketide, alkaloid, depsipeptide, and polyketide–peptide. Enormous structural variety is represented by the marine natural products treated herein. The compounds selected can be considered to represent case examples of significant biomolecules with positivity and, in some cases, potent bioactivity accompanied by an unusual mechanism of action. 1.1.1 Overview of known compounds, highlighting molecules of significance The ocean covers more than 70% of the earth’s surface and is home to exceptional biodiversity: more than one million marine species and an estimated one billion different kinds of marine microbe (Census of Marine Life Press Release 2010). We and others firmly believe that MDSMs represent a continuing resource for tools important in cell biology research and in the design of the next-generation leads for drug discovery and development. The record to date firmly illustrates that the structures of natural products continue to be invaluable in expanding pharmacophore structural space. For example, Newman and Cragg recently provided a detailed analysis of the last 30 years of natural products in drug discovery, wherein they contended that, “Nature’s ‘treasure trove of small molecules’ remains to be explored, particularly from the marine and microbial environments” (Newman & Cragg 2012).
GREW - a scalable frequent subgraph discovery algorithm

Existing algorithms that mine graph datasets to discover patterns corresponding to frequently occurring subgraphs can operate efficiently on graphs that are sparse, contain a large number of relatively small connected components, have vertices with low and bounded degrees, and contain well-labeled vertices and edges. However, for graphs that do not share these characteristics, these algorithms become highly unscalable. In this paper we present a heuristic algorithm called GREW to overcome the limitations of existing complete or heuristic frequent subgraph discovery algorithms. GREW is designed to operate on a large graph and to find patterns corresponding to connected subgraphs that have a large number of vertex-disjoint embeddings. Our experimental evaluation shows that GREW is efficient, can scale to very large graphs, and find non-trivial patterns.
Compressible Lagrangian hydrodynamics without Lagrangian cells

The partial differential Eqs [2.1, 2.2, and 2.3], along with the equation of state 2.4, which describe the time evolution of compressible fluid flow can be solved without the use of a Lagrangian mesh. The method follows embedded fluid points and uses finite difference approximations to \(\vec \nabla\)P and \(\vec \nabla\) · \(\vec u\) to update p, \(\vec u\) and e. We have demonstrated that the method can accurately calculate highly distorted flows without difficulty. The finite difference approximations are not unique, improvements may be found in the near future. The neighbor selection is not unique, but the one being used at present appears to do an excellent job. The method could be directly extended to three dimensions. One drawback to the method is the failure toexplicitly conserve mass, momentum and energy. In fact, at any given time, the mass is not defined. We must perform an auxiliary calculation by integrating the density field over space to obtain mass, energy and momentum. However, in all cases where we have done this, we have found the drift in these quantities to be no more than a few percent.
Non-equilibrium diffusive fluxes of ions and their impact on the refractory period of tightly packed neurons.

Action potentials (APs) generated and sustained by ionic currents flowing through neural cell’s membrane constitute the main way these cells communicate with each other. The most common, although not the only possible mechanism of generating APs, involves sodium influx that ensures cell depolarization and potassium efflux that ensures cell repolaroization. A sodium-potassium exchanger and leakage currents eliminate the ionic disturbance created by an AP. In a closely packed bundle of neuronal cells with fast diffusion of ionic species in the extracellular space (ECS) an AP generated in one axon could impact the excitability of nearby neurons. The ECS is similar in composition to the cerebrospinal fluid that baths the outer surface of the brain and is present in large internal cavities or ventricles and in the spinal canal. The ionic composition of ECS is mostly made of sodium and chloride dissolved in water with much smaller amounts of other substances, including potassium and calcium. Previous studies have considered the role of potassium in seizures by employing a computational model of potassium diffusion between periodically firing neurons [1]. However, absent from most of these studies on diffusion coupling is the potential effect of sodium dynamics on this form of neuronal coupling [2]. Based on previously implemented models that include detailed balances of the main ionic species, we modeled a Hodgkin-Huxley cell able to generate periodic spiking or bursting APs. The model accounts for the dynamics of major (sodium and potassium) ionic species, as well as certain aspects of the extracellular environment (diffusion coefficients, the intracellular/extracellular pace ratio, etc.) The results from the full model were compared to reduced models, in which the dynamics of only one ionic species is considered, through analysis of refractory period induced by a simulated injected current into the neuron. Our results suggest that the refractory period and, therefore, the ability of a neuron to produce regenerative APs depends strongly on the firing rate of nearby neurons and the parameters of the extracellular space (diffusion coefficients and extracellular/intracellular space ratio).
Phospholipids in the Uredospores of Uromyces phaseoli II. Metabolism during Germination

The levels and types of phospholipids changed in distinct phases during the germination of (32)P-labeled uredospores of Uromyces phaseoli. During the first 20 minutes of germination, the phospholipid content dropped to 40% of the pregermination level. Between 2 and 3 hours, phospholipid levels increased to approximately 80% of the pregermination levels, and after germination for 5 hours, catabolism had reduced the (32)P-lipids to about the same level observed prior to the first anabolic phase. A second anabolic phase was observed between 5 and 10 hours of germination. Phosphatidylcholine and phosphatidylethanolamine, the major phospholipids, did not undergo anabolism and catabolism at the same rates during germination. Only small quantities of the more polar phospholipids were released to the germination media.Germinating uredospores were capable of utilizing l-methionine-methyl-(14)C, d,l-(14)C serine, (14)C-choline, and (14)C-ethanolamine for the synthesis of phospholipids. The active one-carbon units from methionine and serine appear to be involved in the methylation of phosphatidylethanolamine to form phosphatidylcholine. Preformed ethanolamine and choline may be incorporated into these two phospholipids also. Evidence for the synthesis of phosphatidylserine, which is subsequently decarboxylated to yield phosphatidylethanolamine, was obtained.
PERFORMANCE STUDIES OF THE DØ PRESHOWER DETECTOR

The DO preshower detector has been tested with cosmic ray muons. We report results on the light yields for minimum ionizing particles and the spatial resolution. The detection efficiency and noise contamination are also investigated.
Phytochemical and pharmacological investigation of Anemopsis californica.

Anemopsis californica was the subject of a phytochemical and pharmacological investigation to determine the plant principle responsible for its reported antispasmodic activity. The extraction procedure yielded among various fractions, leucoanthocyanidins, an unidentified crystalline fraction, and 4-allylveratrole, which was the most active antispasmodic agent. The possibility of antitumor activity attributed to this plant could not be verified by the screens employed.
Finite velocity meson exchange in nuclei.

Many-body techniques are used to develop a practical formalism for including an energy-transfer dependence in the nucleon-nucleon interaction used in nuclear linear response models. An energy-transfer dependence is naturally expected from the exchange of finite mass, finite velocity mesons. The formalism is applied in a Tamm-Dancoff approximation model structure calculation for {sup 16}O. The importance of meson retardation effects on the structure calculation is studied as a function of the magnitude of unperturbed particle-hole energies. The relative importance of ring and ladder contributions is also investigated. It is found that retardation effects can become qualitatively important when particle-hole energies are comparable to the mass of the exchanged meson as would be the case for {ital N}{sup *} particle-nucleon hole configurations. While ladder kernels exhibit a significant energy-transfer dependence, the actual results obtained including retardation when solving for the ladder polarization propagator follow closely the results obtained using an instantaneous ladder kernel. This result suggests a simple procedure for including retardation effects.
Optical frequency domain imaging system and catheters for volumetric imaging of the human esophagus

Barrett's esophagus (BE) is a metaplastic disorder that can undergo dysplastic progression, leading to esophageal adenocarcinoma. Upper endoscopy is the standard of care for screening for BE, but this technique has a relatively low diagnostic accuracy and high cost due to the requirement of conscious sedation. Optical frequency domain imaging (OFDI) is a high-speed imaging modality that generates cross-sectional images of tissues with a resolution of approximately 10µm that is sufficient for detecting microscopic tissue architecture. In combination with a balloon-centering catheter, this method enables BE diagnosis over the entire distal esophagus. Full Text: PDF References S. H. Yun et al.,"High-speed optical frequency-domain imaging", Opt. Exp. 11, 2953 (2003) [CrossRef] J.G. Fujimoto et al.,"Optical biopsy and imaging using optical coherence tomography", Nat. Med. 1, 9 (1995) [CrossRef] G. Zuccaro et al.,"Optical coherence tomography of the esophagus and proximal stomach in health and disease", Am. J. Gastroenterol. 96, 9 (2001) [CrossRef] X. Qi et al.,"Computer-aided diagnosis of dysplasia in Barrett?s esophagus using endoscopic optical coherence tomography", J. Biomed. Opt. 11, 4 (2006) [CrossRef] Y. Chen et al.,"Ultrahigh resolution optical coherence tomography of Barrett's esophagus: preliminary descriptive clinical study correlating images with histology", Endoscopy 39, 7 (2007) [CrossRef] M. J. Suter et al.,"Comprehensive microscopy of the esophagus in human patients with optical frequency domain imaging", Gastrointest Endosc. 68, 4 (2008) [CrossRef] M. J. Cobb et al.,"Imaging of subsquamous Barrett's epithelium with ultrahigh-resolution optical coherence tomography: a histologic correlation study", Gastrointest. Endosc. 71, 2 (2010) [CrossRef] R. C. Haggitt et al.,"Barrett's esophagus, dysplasia, and adenocarcinoma", Human Pathology 25, 10 (1994) [CrossRef] L. M. Brown et al.,"Incidence of Adenocarcinoma of the Esophagus Among White Americans by Sex, Stage, and Age", [CrossRef] R. F. Souza et al.,"Concepts in the Prevention of Adenocarcinoma of the Distal Esophagus and Proximal Stomach", CA: A Cancer J. Clin. 55, 6 (2005) [CrossRef] B. E. Bouma et al.,"Power-efficient nonreciprocal interferometer and linear-scanning fiber-optic catheter for optical coherence tomography", Opt. Lett. 24, 531 (1999) [CrossRef] W. Kang et al.,"Endoscopically guided spectral-domain OCT with double-balloon catheters", Opt. Exp. 18, 17364 (2010) [CrossRef]
Association between Sleep Duration and Intelligence Scores in Healthy Children.

We examined the association between sleep behavior and cognitive functioning in 60 healthy children between 7 and 11 years of age under nonexperimental conditions. Intellectual abilities were assessed by the Wechsler Intelligence Scale for Children (4th edition) and sleep variables by questionnaires, actigraphy, and sleep diaries. Correlation analysis revealed a negative association between sleep duration on weekends and measures of intelligence (full-scale IQ, r = -.29; fluid IQ, r = -.36). The regression coefficient for sleep duration on weekends was -6.11 (SE = 2.09), indicating an increase of 6.11 points on fluid IQ scores for each hour of shorter sleep duration. Attention measures did not correlate with cognitive or sleep variables. Daytime sleepiness as a potential moderator of the relationship between sleep duration and cognitive performance was not related to cognitive or sleep variables. We conclude that children with higher daytime cognitive efficiency (reflected by higher intelligence scores) show increased nighttime efficiency (reflected by shorter sleep duration). In the light of the neural efficiency hypothesis, the current results argue for an extension of the original theory-referring not only to daytime but also to nighttime behavior.
Gender Gaps in Civic and Political Participation in Latin America

This article examines whether there is gender segmentation in civic participation in Latin America, and whether such segmentation is related to gender differences in political participation. Confirming the findings of other studies, this analysis indicates that there is gender segmentation in civic associational activities, and that men are more involved than women in political activities, except for voting. Among those involved in civic activities, however, women attend meetings more often than men or about equally in all types of activities under consideration, except for sports and recreational pursuits. This highlights the need to differentiate between type and intensity of civic participation and provides empirical evidence that Latin American women have strong community ties through a variety of organizations. The regression analysis shows that civic engagement has a positive effect on political participation but that the magnitude of that effect varies by gender depending on the activity.
Modulation of cIAP-1 by Novel Antitubulin Agents When Combined with Bryostatin 1 Results in Increased Apoptosis in the Human Early Pre-B Acute Lymphoblastic Leukemia Cell Line Reh

Previous studies have shown that bryostatin 1 induces a decrease in the expression of the antiapoptotic protooncogene Bcl-2 in the human acute lymphoblastic leukemia (ALL) cell line Reh. This down-regulation has been shown to reduce drug resistance of the Reh cells to anti-tubulin polymerization agents. In the present study we investigated the effect of bryostatin 1 alone and in combination with novel anti-tubulin agents (dolastatin 10 and auristatin PE) and the chemotherapeutic vincristine on the inhibitor of apoptosis protein cIAP-1. Cells were cultured with bryostatin 1 (1 nM), dolastatin 10 (0.1 ng/ml), auristatin PE (0.1 ng/ml), or vincristine (0.5 ng/ml) alone or the combination of these anti-tubulins with bryostatin 1. Western blots were conducted to assess the effects of the above agents on cIAP-1 protein level. Flow-cytometric analysis [7-amino-actinomycin D (7AAD)] was conducted to assess apoptosis as well as staining for morphology using tetrachrome stain. Our results show that cIAP-1 is induced in a time-dependent fashion after bryostatin 1 exposure up to 72 h. However, upon treatment of cells with a combination of bryostatin 1 and dolastatin 10 or auristatin PE, the induction of cIAP-1 was abolished, leading to a significant increase in apoptosis. The initial 24- and 48-h reduction in cIAP-1 protein level recorded in the bryostatin 1 and vincristine combination recovered to control levels by 72 h. We believe that this phenomenon is responsible for the reduced apoptosis recorded in this combination. Results of this study should prove useful in guiding the clinical application of these novel agents in the treatment of ALL.
Effects of Antibiotic Treatment on Clinical Conditions and Bacterial Growth With Guided Tissue Regeneration

Mucogingival flaps were reflected over pairs of mandibular molar teeth with Class II furcation invasions. The dimensions of the furcations were measured. The teeth were debrided and an expanded polytetrafluoroethylene (e-PTFE) membrane was placed and retained over one furcation of each pair (test site) for 4 weeks. The second site served as a control. Eight patients (group 1) with 12 e-PTFE sites received no antibiotic. Seven patients (group 2) with 12 e-PTFE sites were administered amoxicillin/clavulanate potassium for 10 days. Paper-points were used to collect bacterial samples and clinical indices were recorded at baseline and weekly for 4 weeks. Paper-point samples and the e-PTFE collected at week 4 were sonicated and analyzed by DNA probes for seven putative pathogens. At baseline no parameter showed statistical differences between groups or sites. At week 1 significantly greater levels of Prevotella intermedia type I (P <0.05) and Fusobacterium nucleatum (P <0.01) were found in group 1. At week 4, p...
Comparison of high pulse repetition frequency and continuous wave doppler echocardiography in the assessment of high flow velocity in patients with valvular stenosis and regurgitation

Continuous wave Doppler echocardiography has proved useful in detecting and quantitating the high velocity flow disturbances that characterize many stenotic and regurgitant valvular lesions. Pulsed Doppler echocardiography, in contrast, is limited in its ability to quantitate the high velocities that are detected. Recently, new pulsed Doppler systems have been developed that employ high pulse repetition frequencies and can theoretically measure higher flow velocities than those measured by the standard pulsed Doppler systems. To determine the ability of high pulse repetition frequency Doppler echocardiography to accurately measure high velocity flow signals in comparison with the continuous wave method, 80 patients undergoing routine echocardiographic examination for the assessment of valvular heart disease were studied using both techniques. A total of 113 high velocity flow disturbances were detected in 68 patients. In 41 instances, the maximal velocities by the two methods were within 0.5 m/s of each other. In 68 of the 113 high velocity lesions, however, the high pulse repetition frequency technique underes timated the peak velocity found with continuous wave Doppler echocardiography by more than 0.5 m/s. Comparison of the peak velocities recorded by the two methods for the total group showed no significant correlation (r = 0.04, p = NS). Comparison of the difference in peak velocities obtained by the two techniques with the maximal continuous wave velocity (n = 94, r = 0.70, slope = 0.71) suggested that the underestimation becomes greater as the peak velocity increases. Fifteen of the study patients with aortic stenosis subsequently underwent catheterization. Using the simplified Bernoulli equation (p2 - p1 = 4V2), an estimated peak aortic gradient was calculated from both the continuous wave and high pulse repetition frequency data. The predicted continuous wave gradient correlated well with catheterization data (r = 0.89, p = 0.001); however, there was no significant (r = 0.49, p = NS) relation between the gradient predicted from the high pulse repetition frequency Doppler recordings and the measured gradient.
The Effect of Cryogenic Freezing on the Quality of Soft and Hard Shell Lobsters (Homarus americanus)

ABSTRACT Crusher claws, tails and whole lobsters from soft and hard shell lobsters (Homarus americanus), were frozen cryogenical-ly using liquid CO2 and stored for 9 months at −18°C. At three month intervals sensory evaluation, chemical and physical analyses were conducted to examine changes in quality. Lobster meat from the prepared tails and whole hard and soft shell samples maintained good lobster flavor and texture during the storage period.
Technical requirements to become an osteopathic physician

Abstract A person must possess specific abilities in order to become an osteopathic physician. The acquisition of knowledge, the ability to apply the knowledge and the ability to perform appropriate treatment are necessary for students in training. A student needs to have the ability to develop a skill set to progress to the level necessary in both learning and skill acquisition before matriculating into an osteopathic training institution. The abilities necessary for a person to be able to progress to a practicing DO are discussed in this article, as well as the issues that led to the development of a recommended technical standards document. Potential issues are raised, and the currently accepted skills are also discussed.
A case of atypical hemolytic uremic syndrome successfully treated with eculizumab.

Atypical hemolytic uremic syndrome (aHUS) is a rare thrombotic microangiopathy (TMA) characterized by the triad of hemolytic anemia, thrombocytopenia, and acute renal failure. Eculizumab, a monoclonal complement C5 antibody which prevents the induction of the terminal complement cascade, has recently emerged as a therapeutic option for aHUS. We report a case of aHUS successfully treated with eculizumab. A 51-year-old male was admitted to the hospital following a mechanical fall. His past medical history was significant for rheumatic valve disease and mitral valve replacement; he was on warfarin for anticoagulation. A computed tomography scan of the head revealed a right-sided subdural hematoma due to coagulopathy resulting from a supratherapeutic international normalized ratio (INR). Following treatment with prothrombin complex concentrate to reverse the INR, urine output dropped and his serum creatinine subsequently increased to 247.52 µmol/l from the admission value of 70.72 µmol/l. Laboratory evaluation was remarkable for hemolytic anemia, thrombocytopenia, elevated lactate dehydrogenase (LDH), low haptoglobin, and low complement C3. A renal biopsy was consistent with TMA, favoring a diagnosis of aHUS. Treatment with eculizumab was initiated which resulted in the stabilization of his hemoglobin, platelets, and LDH. Hemodialysis was terminated after 2.5 months due to improvement in urine output and solute clearance. The interaction between thrombin and complement pathway might be responsible for the pathogenesis of aHUS in this case. Eculizumab is an effective therapeutic agent in the treatment of aHUS. Early targeting of the complement system may modify disease progression and thus treat aHUS more effectively.
Isotope effect in high- T c superconductors

For high-${T}_{c}$ superconductors in which transition temperatures ${T}_{c}$ are reduced by doping, the oxygen isotope effect (OIE) coefficient in ${T}_{c}$ is shown to increase systematically with the pair-breaking rate and with the valence difference between the substituted and native ions. Moreover, the OIE in ${T}_{c}$ tends to zero as one approaches optimum (or ideal) stoichiometry at which the quality of the superconducting condensate is maximized. In materials with isovalent substitutions, e.g., Sr for Ba or Zn for Cu in $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$, the small OIE of the parent (unsubstituted) compound is magnified owing to pair-breaking disorder. In materials with heterovalent substitutions, e.g., La or Pr for Ba, where carrier densities are necessarily changed, pair breaking induces a much larger OIE. A seminal case is Pr-doped $\mathrm{Y}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$, where data were previously misinterpreted owing to the false assumption that Pr substitutes only for Y. It is now clear, however, that the decrease in ${T}_{c}$ observed with Pr doping actually arises from pair breaking caused by Pr-on-Ba-site defects introduced during crystal growth. When $\mathrm{Pr}{\mathrm{Ba}}_{2}{\mathrm{Cu}}_{3}{\mathrm{O}}_{7\ensuremath{-}\ensuremath{\delta}}$ is grown correctly without such defects, ${T}_{c}$ remains unchanged (as in the case of most other rare-earth substitutions for Y). Invariance of ${T}_{c}$ under a 60% rare-earth mass increase provides strong evidence against phononic pairing mechanisms. The fact that ${T}_{c}$ drops when Pr substitutes for Ba but not for Y indicates that the superconducting hole condensate resides in the BaO layers, where pair breaking degrades ${T}_{c}$ and dramatically increases the OIE. Superconductive pairing modeled on Coulomb coupling between the hole (BaO) and the electron $(\mathrm{Cu}{\mathrm{O}}_{2})$ layers is shown to resolve the serious shortcomings inherent in approaches based on electron-phonon interactions and is found to be generally applicable. Moreover, the OIE in the magnetic penetration depth in alloys is shown to be constant, with degradation of ${T}_{c}$ up to 50%, and thus is unrelated to the OIE in ${T}_{c}$.
Effect of differential saturation on the spatial localization performance of Depth pulses

Computer simulations of Depth pulse B (theta; (2 theta [+/- x, +/- y])2; acquire) and other Depth pulses, verified by experimental surface coil NMR studies utilizing phantom samples, reveal that the spatial localization performance of Depth pulses degrades when the repetition time is short relative to T1 because of differential saturation, i.e. T1 discrimination effects. Simulations of Depth pulse A (theta; 2 theta [+/- x, +/- y]; acquire) and Depth pulse B indicate that there is no phase-cycled pulse sequence delivery order which negates the untoward effect of T1 discrimination on spatial localization performance. The results of this study demonstrate the importance of consistent magnetization preparation prior to the delivery of each phase-cycled multiple pulse sequence in a Depth pulse cycle for obtaining optimal spatial localization performance. The untoward effects of inconsistent magnetization preparation, resulting from T1 discrimination, may be ameliorated by the application of many Depth pulse cycles.
The presence of transfer RNA in the axoplasm of the squid giant axon

Previous work has revealed that 4S RNA is the primary species of RNA in the axoplasm from the giant axons of the squid and Myxicola. This study shows that axoplasmic 4S RNA from the squid giant axon has the functional properties of tRNA. Axoplasmic RNA was charged with amino acids by aminoacyl-tRNA synthetases prepared from squid brain. Tthe aminoacylation was prevented by incubating the RNA with RNase prior to running the reaction. The amino acid-RNA complex was labile at pH 9, which is characteristic of the acyl linkage between an amino acid and its tRNA. Aminoacyl-tRNA synthetase activity was also present in the axoplasm, primarily in the soluble fraction.
Modeling and simulation of co-current moving bed gasification reactors — part I. A non-isothermal particle model

Abstract A non-isothermal model was developed for gasification of a single char particle in an environment of a gas mixture commonly occurring in moving bed reactors. The model, describing the heterogeneous reactions between gases and a porous char particle, was based on the consideration of simultaneous energy and mass conservation principles with changing physical properties as reactions proceed. The model solving process utilized the Fredholm integral technique, converting the resultant differential equations into non-linear algebraic equation systems. Results from the model indicated that the intra-particle gradients of gas concentrations, temperature and carbon conversion profiles became more pronounced as the particle size and/or the bulk fluid temperature increased, due to the effect of diffusional limitations. The carbon conversion is volumetric, having a higher fractional conversion at the particle surface and decreasing towards the center during the gasification process.
Forests and Trees: The Role of Academics in Legislative Internships.

The primary form of experiential education in political science is an internship in a government office. Too often, however, with little actual monitoring of their experiences, government interns become little more than classic office “gofers.” Fortunately, there are strategies to make political internships not only useful learning experiences for students but also productive ventures for the offices employing student. These strategies can be subsumed under two general rules. Rule number one, successful internships require systematic and proactive monitoring prior to, during, and immediately following the internship experience. And rule number two, political internships require a coterminous academic component that serves to provide theoretical “forests” for the empirical “trees” of the actual experience. This article elaborates on these two rules.
Fluctuations in two osmoregulatory components, urea and sodium chloride, of the clearnose skate, Rafa eglanteria bosc 1802—II. Upon natural variation of the salinity of the external medium

Abstract 1. 1. Clearnose skates, Raja eglanteria , were captured from water in which salinity ranged from 18.0 to 33.2% and temperature extremes were 19.0 and 27.0°C. 2. 2. Although serum chloride values ranged from 216 to 284 mmoles/l, no definite depression of chloride values related to dilution of seawater could be demonstrated. 3. 3. Urea values varied from 316 to 427 mmoles/l and were depressed at lower salinities although urea values and the resultant serum osmotic pressures were higher at low salinities than expected. 4. 4. It is suggested that at low salinities, the relatively high serum osmotic pressure may increase hydration and glomerular filtration beyond the capacity of the kidney tubules to effectively absorb certain significant metabolites and therefore prevent this skate's successful habitation of salinities less than 18.0%o.
A General Model for Nucleic Acid Helicases and Their “Coupling” within Macromolecular Machines

In this article we present a general framework that can highly processive, efficient, specific for the type (DNA be used to describe the molecular mechanisms whereby or RNA) of ssNA substrate (lattice) to which they bind, ATP-driven helicases separate and rearrange the com- and directional (59!39 or 39!59) in their movements plementary strands of double helical nucleic acids. This along the target ssNA lattice (for a general review of framework also permits us to consider how these heli- helicase mechanisms see Lohman and Bjornson, 1996). cases might be functionally coupled to other compo- The processivity of a helicase at a given lattice (e.g., nents within the macromolecular machines that carry template) position is defined as the probability that the out physiological processes. We then proceed to define helicase at that position will continue to translocate forparameters that can be used to quantify helicase func- ward by one step along the NA substrate, divided by tion and derive simple thermodynamic equations that the probability that the helicase will dissociate from the describe helicase reactions in isolation and in coupled substrate lattice at that position. The processivity of a systems. helicase is often regulated by additional protein compoAspects of the molecular mechanisms of helicase nents or “coupling” factors, which may interact with the function are then developed using known systems of helicase either directly, or indirectly via the nucleic acid increasing complexity. We begin by considering simple components of the system (see Table 1 and below). DNA “melting proteins” that can—under some condi- Such processivity coupling factors can be operationally tions—open DNA without binding or hydrolyzing ATP. defined as components that interact functionally with We then discuss the cargo-carrying molecular motors the helicase to “trap” intermediate ssNA reaction prodthat, like helicases, use the chemical free energy of ATP ucts of the dsNA opening reaction and facilitate their hydrolysis to translocate directionally along specific cy- subsequent use (e.g., as an ssNA template) by the macromolecular machine within which the helicase operates toplasmic “tracks” but do not, of course, “open” the
Reinforcement shape effects on the fracture behavior and ductility of particulate-reinforced 6061-Al matrix composites

Particle shape effects on the fracture and ductility of a spherical and an angular particulate-reinforced 6061-Al composite containing 20 pct vol Al2O3 were studied using scanning electron microscopy (SEM) fractography and modeled using the finite element method (FEM). The spherical particulate composite exhibited a slightly lower yield strength and work hardening rate but a considerably higher ductility than the angular counterpart. The SEM fractographic examination showed that during tensile deformation, the spherical composite failed through void nucleation and linking in the matrix near the reinforcement/matrix interface, whereas the angular composite failed through particle fracture and matrix ligament rupture. The FEM results indicate that the distinction between the failure modes for these two composites can be attributed to the differences in the development of internal stresses and strains within the composites due to particle shape.
Biomass and Natural Gas to Liquid Transportation Fuels and Olefins (BGTL+C2_C4): Process Synthesis and Global Optimization

This paper introduces a process synthesis and a global optimization framework toward the coproduction of liquid fuels and olefins from biomass and natural gas. A superstructure of alternatives is developed at each stage of the process with different gasification options, natural gas conversion routes, hydrocarbon production, and upgrading methods. Simultaneous heat, power, and water integration is introduced for the optimal usage of the utilities in the proposed plants. The global optimization framework with a branch-and-bound approach is utilized to determine the optimal process out of numerous alternatives that would give the maximum plant profit. The optimal topologies obtained suggest that the best possible process depends on the liquid fuels and olefins to be produced. Parametric analysis on different chemicals production levels suggests that both the profit and net present value (NPV) increases substantially at higher chemicals production levels. Economies of scale are present as the case studies at...
Globin gene transfer for the treatment of severe hemoglobinopathies: a paradigm for stem cell‐based gene therapy

The prospect of treating blood disorders with genetically modified stem cells is highly promising. This therapeutic approach, however, raises a number of fundamental biological questions, spanning several research fields. Further investigation is required to better understand how to isolate and efficiently transduce hematopoietic stem cells (HSCs), while preserving optimal homing and self-renewing properties; how to design safe vectors permitting controlled expression of the transgene products; and how to promote host repopulation by engrafted HSCs. This article addresses basic issues in stem cell-based gene therapy from the perspective of regulating transgene expression, taking globin gene transfer for the treatment of severe hemoglobinopathies as a paradigm.
C1q nephropathy in the pediatric population: pathology and pathogenesis

C1q nephropathy was originally described nearly 25 years ago by Jennette and Hipp. Since that time there have been a limited number of publications on C1q nephropathy, most of them in the pediatric literature. Despite reported incidences as high as 16% in some pediatric biopsy series, a consensus definition on the diagnosis of C1q nephropathy is lacking and its existence as a distinct clinical disease entity remains controversial. The purpose of this review is to discuss the biology of C1q in the context of mechanisms of C1q deposition, and to provide a detailed analysis of the published pediatric case series with a focus on the pathological criteria used to establish the diagnosis of C1q nephropathy as well as long-term outcomes in children.
Contribution of an alveolar cell of origin to the high-grade malignant phenotype of pregnancy-associated breast cancer

Pregnancy-associated breast cancers (PABCs) are tumors diagnosed during pregnancy or up to 5 years following parturition, and are usually high-grade, connective tissue-rich, and estrogen receptor (ER)/progesterone receptor-negative. Little is known about the cellular origin of PABCs or the mechanisms by which PABCs are initiated. Using the RCAS retrovirus to deliver the ErbB2 oncogene into the mammary epithelium of our previously reported MMTV-tva transgenic mice, we detected high-grade, poorly differentiated, stroma-rich and ER-negative tumors during pregnancy and lactation. These high-grade and stroma-rich tumors were less frequent in involuted mice or in age-matched nulliparous mice. More importantly, by generating a WAP-tva transgenic line for expression of ErbB2 selectively in WAP(+) mammary alveolar cells, we found that tumors had similar morphological phenotypes (high grade, poorly differentiated, stroma-rich and ER-negative), irrespective of the time since pregnancy and even in the absence of pregnancy. These data suggest that PABCs arise preferentially from an alveolar cell population that expands during pregnancy and lactation. This somatic mouse model may also be useful for preclinical testing of new prophylactic and therapeutic strategies against PABC.
Equilibrium interactions of corepressors and coactivators with agonist and antagonist complexes of glucocorticoid receptors.

Corepressors and coactivators can modulate the dose-response curve and partial agonist activity of glucocorticoid receptors (GRs) complexed with agonist and antagonist steroids, respectively, in intact cells. We recently reported that GR-antagonist complexes bind to the coactivator TIF2, (transcriptional intermediary factor 2), which is consistent with the whole-cell effects of coactivators being mediated by direct interactions with GR complexes. We now ask whether the whole-cell modulatory activity of corepressors also entails binding to both GR-agonist and -antagonist complexes and whether the association of corepressors and coactivators with GR complexes involves competitive equilibrium reactions. In mammalian two-hybrid assays with two different cell lines and in cell-free pull-down and whole-cell immunoprecipitation assays, the corepressors NCoR (nuclear receptor corepressor) and SMRT (silencing mediator of retinoid and thyroid hormone receptor) associate with agonist and antagonist complexes of GRs....
Gouty Tophi: A Squamous Cell Carcinoma Mimicker?

BACKGROUNDDigital lesions can have a broad differential diagnosis. Squamous cell carcinoma (SCC), the most common digital malignant neoplasm, must be excluded as the cause of persistent digital lesions causing nail dystrophy.OBJECTIVETo describe a patient with a periungual hyperkeratotic lesion on t
Relation between cell growth and cell division II. The effect of cell size on cell growth rate and generation time in Amoeba proteus

Abstract 1. 1. Exposing dividing Amoeba proteus to strong light results in an unequal division. The effect is explainable on the basis of the negative phototropism of this organism. 2. 2. Normal and abnormally large and small post-telophase amoebae produced by unequal division were weighed on the Cartesian diver balance, and the subsequent generation times for these cells were recorded. Growth curves by weight for a large post-telophase cell and a small post-telophase cell were also determined. A large cell grows more slowly but still has a shorter than normal generation time. A small cell grows more rapidly and divides later than the normal. In all cases the post-telophase cells reach the normal division size at the next division, and a pre-division period of “no growth” is always apparent. As cell size increases, the growth rate drops. 3. 3. Cell size and growth appear to be under nuclear control.
Average and detailed modeling approaches emphasizing subsystems in a hybrid mobile refrigeration

Averaging-based and detailed dynamic models of hybrid electric power systems are presented, with emphasis on electric machines and drives. The objective is to compare technical and practical aspects associated with hybridization of refrigeration units in delivery trucks. Challenges unique to this hybrid application, including the thermal system interface and drive-cycle response, are introduced. The system topology is presented, and modeling approaches for each major subsystem, including an ac machine, the battery set, and converters, are discussed. An average modeling technique is fast enough to allow system-level power and efficiency to be evaluated over a long time interval. Compared to the average model, a detailed model including transient response and harmonics gives more accurate power loss estimates at the cost of slower simulation speed. The two models, interfaced with the thermal system, are examined with simulation studies in MATLAB/Simulink, showing the features of each model. Experimental setup and results are presented to validate the models.
Effect of Stilbestrol on the Mammary Gland of the Mouse, Rat, Rabbit, and Goat*

Summary Subcutaneous injections of stilbestrol at low dosages caused extensive duct proliferation in male mice in 2 to 4 weeks. Mammary development did not proceed farther in spayed virgin female mice similarly treated. Oral administration of stilbestrol to male mice required approximately six times as high a dosage as by injection to obtain similar results. Castrate male rats required a higher dosage of stilbestrol than did mice to obtain mammary duct growth. Four-tenths gamma per day of stilbestrol subcutaneously was adequate to secure extensive mammary duct development in male rabbits. After 40 to 60 days treatment early lobule development was apparent. Percutaneous administration was also effective. Mammary glands from two rabbits with subcutaneous pellets had well developed lobule-alveolar systems and responded well to lactogen treatment at 90 days. Normal females tended to lactate on stilbestrol injection alone. Subcutaneous injection of stilbestrol into virgin goats caused abundant and prolonged lactation from lobule-alveolar glands. Little increase in extent of glands was apparent. Subcutaneous administration followed by pellet implantation caused no mammary gland development in a castrate male goat, although the teats were hypertrophied.
Designs for a compact Ni-like-tungsten x-ray laser

We propose a scheme for a compact nickel-like-tungsten soft-x-ray laser operating on the $4d$-$4p$, $J=0\ensuremath{-}1$ transition at 43.2 \AA{}. High gains are achieved by operating at high electron densities ${(n}_{e}g{10}^{22}$ cm${}^{\ensuremath{-}3})$. In this regime, the gain during nonequilibrium ionization can greatly exceed that of the steady state. The duration of this transient gain is on the order of the ionization time, which makes picosecond-pulsed optical pumps ideal. Two target designs, solid tungsten slabs, and tungsten aerogels foams, are considered. We predict gains of 220 cm${}^{\ensuremath{-}1}$ for a 1-$\ensuremath{\mu}$m pump of intensity $I=2.5\ifmmode\times\else\texttimes\fi{}{10}^{16}$ W/cm${}^{2}$.
Use of Futures Markets for Exports by Less Developed Countries

There is no question that the contribution of primary commodity exports to national income is critical to many less developed countries (LDCs). The problem of instability in LDC export revenues has provoked the analysis and implementation of a variety of export strategies. These strategies have generally concentrated on moderating the variability in prices received for commodity exports. Schemes such as buffer stocks, buffer funds, and export quotas are aimed at reducing price variability. These nonmarket strategies have met with limited success because of insuf-
Synoptic charts of solar 9.1 cm and coronal hole data

Synoptic charts for Carrington rotations 1601–1605 (May–August, 1973) were prepared using the central meridian column of the daily 9.1 cm Stanford solar radio maps. These charts were especially contoured to emphasize temperatures near the quiet solar disk level. Synoptic charts of coronal holes from the ATM-Skylab were superimposed on the radio data to investigate the ability of the radio charts to show coronal holes. This brief period is unfortunately the only interval for which both sets of data are available. The conclusion reached is that in spite of certain problems due to active regions, side-lobe effects and a rather large beamwidth, the 9.1 cm synoptic charts can be of substantial value in identifying large coronal holes, especially during periods of low solar activity. Such synoptic charts, therefore, for the years 1962–1973 that Stanford data are available, could enhance significantly the meagre data pool for coronal holes prior to the Skylab mission.