cssi/SciSciGPT-SciSciNet huggingface dataset:
Chapter 9 – Token Ring

Publisher Summary This chapter presents an overview of token ring networks, IEEE 802.5. Unlike Ethernet/802.3 local area networks (LANs) in which nodes contend for media access, token ring LANs use a token passing scheme—that is, media access in token ring LANs is controlled by the possession of a token. The general issues relating to token passing are discussed including a comparison between the random access and the token passing protocols. The IEEE standards include a second token passing protocol called token bus. A token bus network is characterized as a logical ring on a physical bus. Physically, the network resembles a bus topology, but logically, the network is arranged as a ring with respect to passing the token from lobe to lobe. A token ring network is a local area network (LAN) technology based on a token-passing protocol for media access control. Data frames on a token ring network are transmitted from node to node, in either a clockwise or counterclockwise direction, over a point-to-point link. A token ring LAN is implemented either as a logical ring using a physical ring topology, or as a logical ring structure arranged in a physical star configuration. It is also possible to extend the configuration to include a ring consisting of several interconnected hubs.
Activation of Astrocytes in the Dorsomedial Striatum Facilitates Transition From Habitual to Goal-Directed Reward-Seeking Behavior.

Abstract Background Habitual reward-seeking behavior is a hallmark of addictive behavior. The role of the dorsomedial striatum (DMS) in regulating goal-directed reward-seeking behavior has been long appreciated. However, it remains unclear how the astrocytic activities in the DMS differentially affect the behavioral shift. Methods To investigate the astrocytic activity-driven neuronal synaptic events and behavioral consequences, we chemogenetically activated astrocytes in the DMS using GFAP promoter–driven expression of hM3Dq, the excitatory DREADDs (designer receptors exclusively activated by designer drugs). First, we confirmed the chemogenetically induced cellular activity in the DMS astrocytes using calcium imaging. Then, we recorded electrophysiological changes in the synaptic activity of the two types of medium spiny neurons (MSNs): direct and indirect pathway MSNs. To evaluate the behavioral consequences, we trained mice in nose-poking operant chambers that developed either habitual or goal-directed reward-seeking behaviors. Results The activation of DMS astrocytes reduced the frequency of spontaneous excitatory postsynaptic currents in the direct pathway MSNs, whereas it increased the amplitude of the spontaneous excitatory postsynaptic currents and decreased the frequency of spontaneous inhibitory postsynaptic currents in the indirect pathway MSNs. Interestingly, astrocyte-induced DMS neuronal activities are regulated by adenosine metabolism, receptor signaling, and transport. Importantly, mice lacking an astrocytic adenosine transporter, ENT1 (equilibrative nucleoside transporter 1; Slc29a1), show no transition from habitual to goal-directed reward-seeking behaviors upon astrocyte activation, while restoring ENT1 expression in the DMS facilitated this transition. Conclusions Our findings reveal that DMS astrocyte activation differentially regulates MSNs’ activity and facilitates shifting from habitual to goal-directed reward-seeking behavior.
Lumbar Movement Dysfunction Based on Movement Control Impairment Classification System in Those Who Do and Do Not Develop Transient Low Back Pain During Prolonged Sitting.

Abstract Objective Long-term sitting triggers movement-related disorders. We used a movement control impairment (MCI) system to investigate lumbar movement dysfunction in those who did and did not develop transient low back pain (LBP) during prolonged sitting. Methods Twelve patients who did and did not develop transient LBP during sitting for 2 hours were enrolled. We tested the movement control abilities of the 2 groups using 6 MCI tests (12 test items). Results The mean MCI test score in the transient LBP developer group was significantly higher than that in the LBP non-developer group (P = .03). Lumbar flexion movement control as the backward rocking test was significantly more common in the transient LBP developer than in the LBP non-developer group (P .05). However, pelvic shifting during side-bending of the trunk was evident only in the LBP group (33%; P = .093). Conclusion The group exhibiting transient LBP had higher positive MCI test scores and exhibited more asymmetry than the other group. Even the non-LBP group exhibited poor lumbar flexion and rotation. Therefore, subjects with subclinical dysfunction caused by prolonged sitting may require homogenous subgroups classification for the early detection of mechanical risk factors and health and functional interventions.
Giant oil discoveries and Chinese state financing: National and subnational level analyses

Abstract The recent surge in China's oil imports coincides with its emergence as the world's largest provider of capital to low-and middle-income countries. We investigate the role of natural resources in attracting Chinese official financing to low-and middle-income countries by exploiting an exogenous variation arising from giant oil discoveries. We use geocoded data on giant oil discoveries and project-level data on global Chinese official financing to examine the impact of giant oil discoveries at the national and subnational levels. Across countries, giant oil discoveries attract 100% more Chinese official financing in the three years following a discovery. Financing is in the form of non-concessional loans and export credit and is directed to non-oil sectors. At the subnational level, giant oil discoveries do not attract Chinese-funded projects to subnational regions where oil is discovered. Despite presenting an opportunity for oil-rich countries to diversify their economies, the increase in non-concessional borrowing from China presents a thread to recipient countries’ debt sustainability.
Electrical Burns of the Maxillofacial Region in Children

Summary Electrical bums constitute protean injuries that challenge the clinician to apply the principles of trauma care knowledgeably and thoroughly in every case.27 Excellent results can be achieved if the principles as dictated by the nature of the injury and treatment outcomes information are applied.
Cannibalism as a potential factor affecting recruitment of the invasive Asian shore crab Hemigrapsus sanguineus

Cannibalism affects the population dynamics of many marine species, but its potential for influencing population sizes of non-native species is not well understood. A series of laboratory experiments was conducted in 2016 to examine the frequency of cannibalism in the Asian shore crab (Hemigrapsus sanguineus) and the factors influencing its rates of occurrence. Predators and prey varied in size from planktonic megalopae (the last larval stage) and the first benthic crab stage to small juveniles (3–6 mm carapace width, CW), large juveniles (7–10 mm CW), and adult crabs (12–15 mm CW). Individual crabs were paired with groups of smaller prey in glass culture dishes with sand and rocks as potential shelter for the prey, both with and without an alternative food source (commercial crab pellets). Adult and large juvenile crabs consumed megalopae, first-stage crabs and small juveniles, regardless of the presence of food. Megalopae were cannibalized the most heavily, and the size difference between predator and prey was an important factor determining cannibalism rates. Cannibalism of settling megalopae and newly settled juveniles by larger conspecifics could affect recruitment to benthic populations of this non-native crab species.
Dynamic Thumb Circumduction Measured With a Wearable Motion Sensor: A Prospective Comparison of Patients With Basal Joint Arthritis to Controls

Purpose The purpose of this study was to compare the active range of motion in patients with thumb carpometacarpal (CMC) arthritis to healthy controls. A secondary objective of this study was to examine the feasibility of using wearable motion sensors in a clinical setting. Methods Asymptomatic controls and patients with radiographic and clinical evidence of thumb CMC joint arthritis were recruited. The experimental setup allowed participants to rest their forearm in neutral pronosupination with immobilization of the second through fifth CMC joints. An electromagnetic motion sensor was embedded into a thumb interphalangeal joint immobilizer, and participants were asked to complete continuous thumb circumduction movements. Data were continuously recorded, and circumduction curves were created based on degrees of motion. Peak thumb abduction and extension angles were also extracted from the data. Results A total of 29 extremities with thumb CMC arthritis and 18 asymptomatic extremities were analyzed. Bilateral disease was present in 64% of patients. Patient age range was 35–83 years, and the control group age range was 26–83 years. The most affected extremities had Eaton stage 3 disease (38%, N = 11). The average maximum thumb abduction was 53.9° ± 19.6° in affected extremities and 70.8° ± 10.1° for controls. Average maximum thumb extension was 50.0° ± 15.2° in affected extremities and 58.4° ± 9.1° for controls. When comparing patients with Eaton stage 3 and 4 disease to controls, average maximum abduction and extension decreased with increasing disease stage (42.3°, 46.1°, and 70.8° for abduction, respectively, and 58.4°, 43.3°, and 41.3° for extension, respectively). Conclusions We observed more severe motion limitations with increasing Eaton stage, and statistically significant differences were seen with stage 3 and 4 disease. A wearable motion sensor using a portable experimental setup was used to obtain measurements in a clinical setting. Type of study/level of evidence Diagnostic II.
Age and the aging process significantly alter the small bowel microbiome.

Summary Gut microbial diversity decreases with aging, but existing studies have used stool samples, which do not represent the entire gut. We analyzed the duodenal microbiome in 251 subjects aged 18–35 (n = 32), 36–50 (n = 41), 51–65 (n = 96), and 66–80 (n = 82). Decreased duodenal microbial diversity in older subjects is associated with combinations of chronological age, number of concomitant diseases, and number of medications used, and also correlated with increasing coliform numbers (p
The well-being of music educators during the pandemic Spring of 2020

The COVID-19 pandemic disrupted many aspects of life, including the instructional practices of music educators. The purpose of this study was to examine music teachers’ well-being following the dis...
Complicated Intramural Hematoma with Medionecrosis of the Aortic Wall

Medionecrosis and medial degeneration are rare complications associated with intramural hematomas (IMHs). We present a case of a 69-year-old Asian female with an IMH with medionecrosis and medial degeneration of the aortic wall. The patient underwent successful surgical intervention, and pathological findings were significant for cystic medial degeneration of the aortic wall.
Recent Developments on the Physiological Basis of Magnetoencephalography (MEG)

This review discusses some of the progress made in recent years toward understanding the nature of generators of MEG signals. Attempts to rigorously relate cellular currents to an MEG signal have forced us to examine in detail the ways by which various currents in the volume conductor can give rise to such a signal. We will first consider this issue theoretically to elucidate how various currents may contribute to the MEG signal, then consider the magnitudes of their contributions determined in a particular experimental paradigm, namely in the in vitro preparation of turtle cerebellum, in order to make some general inferences about the nature of generators of MEG signals.
Panic Attacks and Other Dissociative Disorders

Panic disorder (PD) is one of the most common anxiety disorders. According to the Epidemiologic Catchment Area (ECA) study, PD affects around 2 % of the adult population (Markowitz et al. 1989). Panic attacks can be disabling and may lead to agoraphobia with devastating psychosocial and economic consequences. The identification of the etiology of these attacks is important for the proper management of the disorder.
Experimental investigation of the electrical behavior of olivine during partial melting under pressure and application to the lunar mantle

Abstract Electrical conductivity measurements were performed during melting experiments of olivine compacts (dry and hydrous Fo 77 and Fo 90 ) at 4 and 6 GPa in order to investigate melt transport properties and quantify the effect of partial melting on electrical properties. Experiments were performed in the multi-anvil apparatus and electrical measurements were conducted using the impedance spectroscopy technique with the two-electrode method. Changes in impedance spectra were used to identify the transition from an electrical response controlled by the solid matrix to an electrical response controlled by the melt phase. This transition occurs slightly above the solidus temperature and lasts until T solidus + 75 ° C (±25). At higher temperature, a significant increase in conductivity (corresponding to an increase in conductivity values by a factor ranging from ∼30 to 100) is observed, consistent with the transition from a tube-dominated network to a structure in which melt films and pools become prominent features. This increase in conductivity corresponds to an abrupt jump for all dry samples and to a smoother increase for the hydrous sample. It is followed by a plateau at higher temperature, suggesting that the electrical response of the investigated samples lacks sensitivity to temperature at an advanced stage of partial melting. Electron microprobe analyses on quenched products indicated an increase in Mg# (molar Mg / ( Mg + Fe ) ) of olivine during experiments (∼77–93 in the quenched samples with an initial Fo 77 composition and ∼92–97 in the quenched samples with an initial Fo 90 composition) due to the partitioning of iron to the melt phase. Assuming a respective melt fraction of 0.10 and 0.20 before and after the phase of significant increase in conductivity, in agreement with previous electrical and permeability studies, our results can be reproduced satisfactorily by two-phase electrical models (the Hashin and Shtrikman bounds and the modified brick layer model), and provide a melt conductivity value of 78 (±8) S/m for all Fo 77 samples and 45 (±5) S/m for the Fo 90 sample. Comparison of our results with electromagnetic sounding data of the deep interior of the Moon supports the hypothesis of the presence of interconnected melt at the base of the lunar mantle. Our results underline that electrical conductivity can be used to investigate in situ melt nucleation and migration in the interior of terrestrial planets.
Protein kinase inhibitors: probes for the functions of protein phosphorylation.

Publisher Summary This chapter focuses on low-molecular-weight inhibitors that can be used for studies with intact cells. As the specificity of these inhibitors is a major concern when using them with intact cells, their effects on isolated enzymes ­rather than on intact cells ­is the major focus of the chapter. Several approaches have been taken to find specific inhibitors of protein kinases. Many of the most interesting inhibitors have come from systematic screening of natural products, and these compounds have provided the basis for the synthesis of other more specific inhibitors. While a great deal of progress has been made and some very useful inhibitors have been discovered, the lack of specificity remains a problem. In the future, greater cognizance must be taken of the fact that cells contain a large number of protein kinases and that in vitro results with only a few enzymes cannot be extrapolated to the complex situation in an intact cell. There are several examples where the term “specific protein-kinase inhibitor” has proved to be a misnomer. The results with studies on the effects of protein-kinase inhibitors on intact cells often have rather malleable interpretations.
Liberalism's Illiberal Obligation: The American Revolutionaries and the Duty to Revolt

This paper questions the extent of liberalism’s emphasis of individual choice and liberty by considering its requirement that people have an affirmative duty to rebel against tyrannical, oppressive government. During the run up to 1776, the American Revolutionaries argued that rebellion against British authority was “their duty,” implying that there was an affirmative obligation to revolt regardless of individual interest. Since such an obligation would counteract the liberal focus of individualism, one must question whether the duty to revolt is a real duty or mere rhetoric, arising only to persuade. The duty appears as an actual, binding duty, when one traces its evolution through the discussion surrounding the American Revolution. Further, during this time, the duty to revolt evolves from a purely abstract duty, with no link to factual circumstance, to an actual duty, completely grounded in historical experience. In order to arrive at this conclusion, this paper considers the 1750’s arguments of Jonathan Mayhew, the representative “of advanced American thought” who coined the phrase “no taxation without representation.” It analyzes Mayhew’s discussion of a duty to revolt alongside the philosophic authorities of the era (e.g. Pufendorf, Locke, Montesquieu, and Blackstone). Their arguments not only shed light on the assumptions of Mayhew’s arguments, but help distinguish between categorical duties (i.e. those which one must perform regardless of individual situation) and hypothetical duties (i.e. those which must be performed based upon individual interest). Even though Mayhew’s notion of the duty to revolt appears hypothetical, he does provide guidance for determining when the duty becomes binding on individuals; that is, he explains when the duty turns from hypothetical to categorical. This paper is part of a larger project analyzing the evolution of the duty to revolt from the 1750’s up to the 1780’s. The impetus of this project concerns the necessary conditions for a successful liberal government. For example, if the duty to revolt is categorical, then it is necessary for the citizen body to be on constant guard, monitoring every action of government in case it turns tyrannical. This additional duty requires, at the very least, a vigilant citizenry, freedom of information, and a robust sphere of civic dialogue. Prior to venturing into these practical requirements, it is first necessary to determine the actuality of the curious duty that liberalism, the paragon of freedom, obliges.
Massively Parallel Computation of Discrete Logarithms

Numerous cryptosystems have been designed to be secure under the assumption that the computation of discrete alogarithms is infeasible. This paper reports on an aggressive attempt to discover the size of fields of characteristic two for which the computation of discrete logarithms is feasible. We discover several things that were previously overlooked in the implementation of Coppersmith's algorithm, some positive, and some negative. As a result of this work we have shown that fields as large as GF(2503) can definitely be attacked.
A bootstrap approach to estimating power for linkage heterogeneity.

We examined the power of detecting linkage heterogeneity when the null hypothesis is that all families are linked to one locus (A) and the two alternative hypotheses are either 1) a proportion of the families are linked to locus A and the remaining families are linked to a second locus B or 2) a proportion of the families are linked to locus A or B and a third proportion of the families are unlinked to either locus. The power of detecting linkage heterogeneity is estimated for various proportions of families linked to loci A, B or unlinked to either locus (sampling under the alternative hypothesis). To estimate the significance level, the data set is sampled under the null hypothesis
The End of the Soul: Scientific Modernity, Atheism, and Anthropology in France

The End of the Soul: Scientific Modernity, Atheism, and Anthropology in France. Jennifer Michael Hecht. New York: Columbia University Press, 2003. 402 pp.
Compliant Silicone Elastomer Models of Elastase-Induced Aneurysms in the Rabbit: Model Construction and Hemodynamics

An elastase-induced saccular aneurysm in the rabbit right common carotid artery was developed as a model of human cerebrovascular aneurysm, and used for testing various endovascular devices and therapies. The carotid artery of the rabbit approximates the size of the human middle cerebral artery. Therefore, the created aneurysm is similar to those found in humans around the main branches of the circle of Willis. To minimize the use of animals and gain more insight into the hemodynamics of this model, in addition to the ability to perform early testing of endovascular devices in vitro, we have developed a rapid prototyping technique to produce compliant elastomer replicas of such aneurysms. In this implementation, the geometry of the constructed aneurysm is a representative average. The rapid prototyping system reliably reproduces as many copies of the lumen of the arterial bed out of Polyacrylonitrile-butadiene-styrene (ABS). The ABS output of the prototyping system can be used as a core that is dipped a silicone elastomer and then spin coated until cured. Thereafter, the core is melted away to yield the elastomer replica of the arterial bed. This replica was included in a mock circulation loop for detailed hemodynamic investigation using particle image velocimetry (PIV).Copyright © 2004 by ASME
Academic/Research Librarians with Subject Doctorates: Experiences and Perceptions, 1965-2006

The topic of academic/research librarians with subject doctorates remains largely unexplored. Based on survey data gathered from subject-doctorate holders (excluding those with doctorates in LIS) currently working in U.S. and Canadian academic/research libraries, this article extends the analysis published by the authors in the January 2008 issue of portal: Libraries and the Academy . While the first article featured quantitative analysis to highlight data and trends relating to these librarians over a 40-year period, focusing on their demographic profile, educational background, paths into librarianship, and range of positions, this article analyzes qualitative data to report their perceptions about their work environment and the advantages and challenges of academic librarianship as a career. Providing more information about this group of librarians and their experiences highlights the valuable skills they bring to the academic/research library environment. Moreover, it can help advanced-degree holders to determine whether a career in librarianship is right for them.
αB-Crystallin is expressed in kidney epithelial cell lines and not in fibroblasts

We have recently shown the presence of alpha B-crystallin in non-ocular tissues of diverse embryological origins such as the heart, brain, spinal cord, kidney, retina, etc. Using an alpha B-crystallin-specific antiserum and immunofluorescence, immunoblotting, immunoprecipitation and peptide mapping with Staphylococcus aureus protease, we demonstrate differential expression of alpha B-crystallin in epithelial and fibroblast cell lines. alpha B-Crystallin was detectable only in epithelial cell lines such as MDBK, MDCK, LLCPK1 and JTC-12, and was not observed in two kidney fibroblast cell lines, one skin fibroblast cell line, and one corneal fibroblast cell line. Differential expression of the alpha B-crystallin gene was also confirmed by Northern blot analysis of the RNAs isolated from these cell lines. These data suggest a cell-type-specific role for alpha B.
Lingual co-application of sodium and linoleic acid affects chorda tympani nerve electrophysiological responses.

We previously reported that bilateral transection of the gustatory chorda tympani nerve (CTX) significantly impaired the ability of both male and female rats to detect linoleic acid (LA; a free fatty acid and main component of some kinds of dietary fat). Surprisingly, the chorda tympani nerve (CT) was unresponsive to lingual application of LA alone. LA may require a background of saliva (dilute saline) to activate taste cells. This would explain, in part, the discrepancy between our behavioral data (in which saliva is present) and CT electrophysiological data (in which salivary sodium is rinsed off during water rinses). Moreover, electrophysiological studies of isolated taste receptors have shown that LA inhibits delayed rectifying potassium channels, presumably broadening action potentials, and may thereby augment responses to other taste stimuli. Therefore, we previously examined CT responses to co-application of monosodium glutamate (MSG) and LA. We found that LA enhances CT responses to MSG. However, MSG is a complex stimulus, containing both sodium and glutamate. Therefore, the present study examined CT whole nerve responses to lingual application of dilute NaCl concentrations (55, 65, 75 mM) and to combined application of 88 μM LA and NaCl in male rats. Preliminary data indicate that CT responses to co-application of LA and NaCl were greater than those to NaCl alone. Thus, free fatty acids (such as LA) modulate gustatory responses to taste stimuli (including MSG and sodium), beginning with an initial interaction with salivary sodium. Supported by NIH Grants DC04785 and DC00044.
A Review of Entering Research: A Facilitator’s Manual

Review of : Entering Research: A Facilitator’s Manual ; 1 st ed.; Janet Branchaw, Christine Pfund, and Raelyn Rediske; (2010). W.H. Freeman and Company, New York. 284 pages.
If at First You Don't Succeed, What Makes You Try,Try Again? Effects of Implicit Theories and Ability Feedback in a Performance-Oriented Climate

Previous research has found that having an “entity theory” of personality (construing personal attributes as fixed) generally results in decreased effort after failure, whereas having an “incremental theory” (viewing personal attributes as malleable) produces sustained or increased effort (Dweck, 1999). The present research hypothesized that effort patterns would reverse in a context emphasizing solely performance goals because it would be best suited for entity theorists. Participants were induced to hold an entity or incremental theory regarding a personality characteristic and were given false feedback from a test supposedly measuring that characteristic. Effort was assessed before and after these manipulations. As hypothesized, an entity theory led to increased effort after failure, whereas an incremental theory resulted in decreased effort. These findings suggest the need to view implicit theories of personality within a more complicated framework.
Incomplete response to ursodeoxycholic acid in primary biliary cirrhosis: is a double dosage worthwhile?

Abstract OBJECTIVE: The aim of this study was to assess the safety and efficacy of high-dose ursodeoxycholic acid (UDCA, 28–32 mg/kg/day) in patients with primary biliary cirrhosis (PBC) who had shown an incomplete response to the standard dose (13–15 mg/kg/day). METHODS: A total of 25 patients with PBC who had been on UDCA (13–15 mg/kg/day) therapy for 24–141 months and had shown persistent elevation of ALP activity at least two times the upper limit of normal were enrolled. The dose of UDCA was increased to 30 (28–32) mg/kg/day and given for 1 yr. RESULTS: A significant but marginal improvement in serum ALP activity (707 ± 52 vs 571 ± 32, p = 0.001) was noted at 1 yr of treatment with high-dose UDCA. However, levels of total bilirubin (1.1 ± 0.2 vs 1.0 ± 0.2, p = 0.1), AST (58 ± 9 vs 54 ± 11, p = 0.1), albumin (4.1 ± 0.7 vs 4.0 ± 0.08, p = 0.1), or Mayo risk score (4.13 ± 0.3 vs 4.12 ± 0.3, p = 0.2) remained essentially unchanged. Normalization of liver tests did not occur in any patient, and adverse events were not recorded in any case. CONCLUSIONS: Although UDCA at a dose of 28–32 mg/kg/day is well tolerated, this dosage does not seem to benefit most patients with PBC responding incompletely to a dose of 13–15 mg/kg/day. The results of this pilot study would seem to discourage further controlled trials of high-dose UDCA in suboptimal responders to the standard dose of UDCA.
The Impact of E-Commerce on Entry-Mode Strategies of Service Firms: A Conceptual Framework and Research Propositions:

Abstract This article focuses on the role of e-commerce on the entry-mode choice of service firms. On the basis of recent calls for the reconceptualization of marketing theories and concepts with services as a key component, the authors focus on the interface of e-commerce, services marketing, and foreign market entry-mode choice. The authors offer an integrative conceptual framework that explicates the role of e-commerce on the entry-mode choice of service firms, and they propose that several internal and external factors moderate this relationship. The authors derive several research propositions and offer managerial implications and directions for further research in the timely and exciting domain of services marketing.
Fully Automated DNA Reaction and Analysis in a Fluidic Capillary Instrument

A simple, reliable, automated genetic analysis instrument has been designed and prototyped. The system uses novel fluidic technology, coupling thermal cycling, reaction purification, in-line loading, and capillary electrophoresis in a single instrument. Samples in the loop of an injection valve are amplified inside a rapid air thermal cycler. A liquid chromatographic separation eliminates contaminants and excess salt. The sample is loaded in an efficient, continuous, flow-through manner onto a polymer-filled separation capillary. Detection by laser-induced fluorescence produces signal-to-noise ratios of 1000:1 or greater. Refilling of the polymer-filled capillary is automatic; during the run, the system is reconditioned for injection of another sample. Since all components and connections are fluidic, automation is natural and simple. The instrument is reliable and fast, performing PCR reaction cycling, purification and analysis, all in 20 min. Reproducibility (CV) of retention times is 2% (n = 129) and of peak areas 9% (n = 34). Bubbles and particulates are eliminated by the chromatography column. Adaptation of the instrument prototype for separation of DNA-sequencing reactions is described; cycle sequencing and electrophoresis of a single lane are complete in 90 min. Implications and challenges for development of fully automated fluidic instruments for genomic sequencing are discussed.
Phytogeography of Najas gracillima (Hydrocharitaceae) in North America and its cryptic introduction to California

 Premise of the Study: The discontinuous North American distribution of Najas gracillima has not been explained satisfactorily. Infl uences of extirpation, nonindigenous introduction, and postglacial migration on its distribution were evaluated using fi eld, fossil, morphological, and molecular data. Najas is a major waterfowl food, and appropriate conservation measures rely on accurate characterization of populations as indigenous or imperiled.  Methods: Seed lengths of N. gracillima from native Korean populations, a nonindigenous Italian population, and North American populations were compared using digital image analysis. DNA sequence analyses from these regions provided nine nrITS genotypes and eight cpDNA haplotypes.  Key Results: Najas gracillima seeds from Eurasia and California are shorter than those from eastern North America. Nuclear and chloroplast DNA sequences of N. gracillima from Korea and Italy were identical to California material but differed from native eastern North American plants. Eastern North American specimens of N. gracillima at localities above the last glacial maximum boundary were identical or similar genetically to material from the northeastern United States and Atlantic Coastal Plain and Piedmont but divergent from plants of the Interior Highlands–Mississippi Embayment region.  Conclusions: In California, N. gracillima is nonindigenous and introduced from Asia. In eastern North America, populations that colonized deglaciated areas were derived primarily from refugia in the Atlantic Coastal Plain and Piedmont. Genetic data indicate initial postglacial migration to northeastern North America, with subsequent westward dispersal into the Upper Great Lakes. These results differentiate potentially invasive California populations from seriously imperiled indigenous eastern North American populations.
Measurement of adenine nucleotides in plasma

The goal of this study was to identify the most important variables affecting bioluminescent ATP, ADP and AMP measurements in plasma and to develop an assay that takes these variables into account. Blood samples were drawn from conscious dogs. A 'stop solution' containing EDTA was prepared, which greatly retarded plasma ATP degradation by chelating Mg(+2) and Ca(+2) that are co-factors for many ATPases. Stop solution and blood were mixed using a two-syringe withdrawal system. Samples were centrifuged twice in order to remove red blood cells, and ATP was measured in the supernatant using the firefly luciferase assay. Sample pH was adjusted to the optimal range (7.75-7.95) and Mg(2+) (necessary for the luciferase reaction) was added back to the sample within the luminometer 2 s prior to luciferase addition. Four assay tubes were prepared for each plasma sample, containing standard additions of 0-15 pmol added ATP, in order to quantify native plasma ATP content. In separate plasma/stop solution samples ADP + ATP was measured after converting ADP to ATP via the pyruvate kinase reaction, and AMP + ADP + ATP was measured after addition of both myokinase and pyruvate kinase. Addition of forskolin and isobutylmethylxanthine (IBMX) to the stop solution to inhibit platelets resulted in lower ATP concentrations. Measurement of ATP and haemoglobin from lysed erythrocytes revealed that haemolysis exerts a strong influence on plasma ATP concentration that must be taken into account.
Effects of light intensity on photosynthesis and dark respiration in six species of marine phytoplankton

Using an oxygen polarographic electrode, the shapes of photosynthetic curves and the effects of light on dark respiration in 6 species of marine phytoplankton wer examined. The species used were Skeletonema costatum, Ditylum brightwellii, Cyclotella nana (Thalassiosira pseudonana) (all Bacillariophyceae), Dunaliella tertiolecta (Chlorophyceae), Isochrysis galbana (Haptophyceae), and Gonyaulax tamarensis (Dinophyceae). A hysteresis was observed in all species examined with respect to increasing and decreasing light. Compensation light intensities varied by over 4 orders of magnitude, suggesting that the 1% light depth is an ambiguous measure of the euphotic zone. The data suggest that dark respiration accounts for ca. 25% of gross photosynthesis, but is species-dependent. In addition, respiration versus cell size does not describe an inverse exponential function over the size scales examined.
Transforming growth factor-β controls receptor levels for epidermal growth factor in NRK fibroblasts

NRK fibroblasts exposed to transforming growth factor-beta (TGF-beta) show increased binding of radiolabeled epidermal growth factor (EGF) relative to untreated cells. The binding of another growth factor, rat insulin-like growth factor-II, is unaffected. The increase in EGF binding induced by TGF-beta is not due to inhibition of EGF processing nor to an alteration in the affinity of plasma membrane EGF receptors. However, treatment of the cells with TGF-beta does cause a rapid increase in the number of plasma membrane receptors for EGF. TGF-beta has little effect on the rate of overall protein synthesis, but the increase it induces in EGF binding can be completely inhibited by cycloheximide and tunicamycin. Thus a selective synthetic mechanism underlies TGF-beta action. Cells incubated with TGF-beta also show altered down regulation of their EGF receptors in response to the ligand; concentrations of EGF that can induce strong biological responses no longer decrease the plasma membrane receptor level below the basal state. These results agree well with the known specificity and synergism of the interaction between TGF-beta and EGF. Moreover, they describe a mechanism of growth control in which bioactive peptides act coordinately through a regulatory effect on the number of cell-surface receptors.
Blind separation and equilization using fractional sampling of digital communications signals

Abstract Blind source separation (BSS) in communications applications is usually considered under the assumption that the observed or received signals are instantaneous linear mixtures of the individual sources without intersymbol interference (ISI). Based on a more general structure for multi-input–multi-output channels, we present a method using fractional sampling and BSS to recover transmitted symbols in the presence of ISI. This method is different from traditional ways for dealing with ISI. It can be used successfully even if there are more sources than receivers. Simulation results are given, illustrating the good performance of the method and good agreement between theory and experiments.
Stable mid-latitude red arcs: Observations and theory

The observational features of the arc are fairly well established. At present, the thermal conduction model appears to explain the red arc features most consistently, but it must be noted that a soft electron flux would give very similar results. Ion temperature measurements in the vicinity of an arc, which should be forthcoming in the very near future, can establish conclusively whether transverse electric fields play any important role in the formation of the arcs. Accepting the assumption that the arcs are the result of energy flowing down from the plasmasphere, the major remaining question is: where does the energy come from and how does it get into the plasmasphere? The various proposed mechanisms discussed in the previous chapter appear feasible, but much work needs to be done before this problem is completely resolved.
Dose dependence of mechanical properties in tantalum and tantalum alloys after low temperature irradiation

The dose dependence of mechanical properties was investigated for tantalum and tantalum alloys after low temperature irradiation. Miniature tensile specimens of three pure tantalum metals, ISIS Ta, Aesar Ta1, Aesar Ta2, and one tantalum alloy, Ta-1W, were irradiated by neutrons in the High Flux Isotope Reactor (HFIR) at ORNL to doses ranging from 0.00004 to 0.14 displacements per atom (dpa) in the temperature range 60 C 100 oC. Also, two tantalum-tungsten alloys, Ta-1W and Ta-10W, were irradiated by protons and spallation neutrons in the LANSCE facility at LANL to doses ranging from 0.7 to 7.5 dpa and from 0.7 to 25.2 dpa, respectively, in the temperature range 50 C 160 oC. Tensile tests were performed at room temperature and at 250oC at nominal strain rates of about 10-3 s-1. All neutron-irradiated materials underwent progressive irradiation hardening and loss of ductility with increasing dose. The ISIS Ta experienced embrittlement at 0.14 dpa, while the other metals retained significant necking ductility. Such a premature embrittlement in ISIS Ta is believed to be because of high initial oxygen concentrations picked up during a pre-irradiation anneal. The Ta-1W and Ta-10W specimens irradiated in spallation condition experienced prompt necking at yield since irradiation doses formore » those specimens were high ( 0.7 dpa). At the highest dose, 25.2 dpa, the Ta-10W alloy specimen broke with little necking strain. Among the test materials, the Ta-1W alloy displayed the best combination of strength and ductility. The plastic instability stress and true fracture stress were nearly independent of dose. Increasing test temperature decreased strength and delayed the onset of necking at yield.« less
Residual Methamphetamine in Decontaminated Clandestine Drug Laboratories

This pilot cross-sectional study examined three previously decontaminated residential clandestine drug laboratories (CDLs) in Washington State to determine the distribution and magnitude of residual methamphetamine concentrations relative to the state decontamination standard. A total of 159 discrete random methamphetamine wipe samples were collected from the three CDLs, focusing on the master bedroom, bathroom, living room, and kitchen at each site. Additional samples were collected from specific non-random locations likely to be contacted by future residents (e.g., door knobs and light switches). Samples were analyzed for methamphetamine by EPA method 8270 for semivolatile organic chemicals. Overall, 59% of random samples and 75% of contact point samples contained methamphetamine in excess of the state decontamination standard (0.1 μ g/100 cm 2 ). At each site, methamphetamine concentrations were generally higher and more variable in rooms where methamphetamine was prepared and used. Even compared with ...
An intense auroral zone x-ray event in the 4–5-sec period range

Intense auroral zone X ray pulsation observed following PCA event of September 1966 showing no connection to micropulsation fields
Geoarchaeological evidence for multidecadal natural climatic variability and ancient Peruvian fisheries

Abstract Understanding the influence of natural climatic variability on modern fisheries is complicated by over a century of industrial fishing. Archaeological data provide unique opportunities for assessing precolonial and preindustrial fisheries. Records show that anchoveta-vs sardine-dominated fisheries correlate with 20th-century climate change in the Pacific Basin and are linked to multidecadal climatic variability. The “anchovy regime” is characterized by cooler conditions and lower frequency El Nino/Southern Oscillation (ENSO) events, while the “sardine regime” is associated with warmer conditions and higher frequency ENSO. Fish remains excavated at Lo Demas, an Inca-period (ca. A.D. 1480–1540) fishing site at 13°25′S on the Peruvian coast, document a shift from an anchoveta-to a sardine-dominated fishery at about A.D. 1500. This shift correlates with records for increasing ENSO frequency at the same time. Middle and late Holocene sites have archaeofish assemblages that also suggest regime changes. Here we show that changes in fish regimes can result from natural variability and we support the potential role of archaeological assemblages in tracking multidecadal climate change in the Pacific Basin throughout the Holocene (0–11,500 cal yr B.P.).
Generic overjustification: The interaction of extrinsic rewards

Abstract An experiment was conducted to test the hypothesis that the value of one extrinsic reward will be undermined when another extrinsic reward is made contingent upon the same activity. Subjects were assigned to one of three experimental groups. Some were paid a contingent monetary reward for engaging in a monotonous and boring activity and were then given the opportunity to continue to work voluntarily for additional payment. Others were given both money and extra experimental credit for the required task, and were likewise offered additional pay for voluntary extra work. A third group of subjects received money for the required task, but were given no additional rewards for extra work. It was observed that the money + credit subjects did less extra work for pay than the money-only subjects. They also rated the monetary reward as having been of less value to them. Subjects who were paid during the initial task session but not for extra work did less additional work than those who were paid in both sessions, but did not differ in their ratings of the value of the monetary reward. It is concluded that extrinsic rewards are nonadditive, and that current models of undermined rewards are too limited to account for this phenomenon. A selective attention hypothesis is advanced as an alternative.
NON-PARAMETRIC INFERENCE FOR CUMULATIVE INCIDENCE FUNCTIONS IN COMPETING RISKS STUDIES

In the competing risks problem, a useful quantity is the cumulative incidence function, which is the probability of occurrence by time t for a particular type of failure in the presence of other risks. The estimator of this function as given by Kalbfleisch and Prentice is consistent, and, properly normalized, converges weakly to a zero-mean Gaussian process with a covariance function for which a consistent estimator is provided. A resampling technique is developed to approximate the distribution of this process, which enables one to construct confidence bands for the cumulative incidence curve over the entire time span of interest and to perform Kolmogorov-Smirnov type tests for comparing two such curves. An AIDS example is provided.
A novel radiographic targeting guide for percutaneous placement of transfacet screws in the cervical spine with limited fluoroscopy: A cadaveric feasibility study.

Background We describe a technique for percutaneous transfacet screw placement in the cervical spine without the need for lateral-view fluoroscopy.
Behavioral and neural bases of extinction learning in Hermissenda.

Extinction of classical conditioning is thought to produce new learning that masks or interferes with the original memory. However, research in the nudibranch Hermissenda crassicornis (H.c.) has challenged this view, and instead suggested that extinction erased the original associative memory. We have re-examined extinction in H.c. to test whether extinguished associative memories can be detected on the behavioral and cellular levels, and to characterize the temporal variables involved. Associative conditioning using pairings of light (CS) and rotation (US) produced characteristic suppression of H.c. phototactic behavior. A single session of extinction training (repeated light-alone presentations) reversed suppressed behavior back to pre-training levels when administered 15 min after associative conditioning. This effect was abolished if extinction was delayed by 23 hr, and yet was recovered using extended extinction training (three consecutive daily extinction sessions). Extinguished phototactic suppression did not spontaneously recover at any retention interval tested (2-, 24-, 48-, 72-hr), or after additional US presentations (no observed reinstatement). Extinction training (single session, 15 min interval) also reversed the pairing-produced increases in light-evoked spike frequencies of Type B photoreceptors, an identified site of associative memory storage that is causally related to phototactic suppression. These results suggest that the behavioral effects of extinction training are not due to temporary suppression of associative memories, but instead represent a reversal of the underlying cellular changes necessary for the expression of learning. In the companion article, we further elucidate mechanisms responsible for extinction-produced reversal of memory-related neural plasticity in Type B photoreceptors.
Diacylglycerol kinase ζ deficiency in a non-CD4(+) T-cell compartment leads to increased peanut hypersensitivity.

Peanut sensitization in diacylglycerol kinase zeta (DGKζ) deficient mice led to elevated peanut-IgE levels and severe anaphylaxis. DGKζ deficient CD4+T cells did not account for the phenotype. Future studies will determine which immune lineage caused increased food hypersensitivity.
Men's and women's ratings of life satisfaction by age of respondent and age interval judged

A total of 432 people in six age groups rated the satisfaction of their current, past, and projected future lives. Average ratings for men and women did not differ. However, the triple interaction of sex × age of respondent × age interval judged indicated an optimism toward the future on the part of women. Compared with men of the same age, women judged the age interval prior to their own, as well as their present age interval, as being less satisfying than did the men. But women expected levels of satisfaction in the future to be higher than men expected. This optimism is attributed to socialization differences as well as the hope engendered by the current feminist movement.