cssi/SciSciGPT-SciSciNet huggingface dataset:
Power system characteristics for more electric aircraft

It should not be suprising that more electric aircraft must meet significantly more difficult electrical power system requirements than were considereed when today's power distribution systems were being developed. Electric power, no longer a secondary system, will become a critical element of the primary control system. Functional reliability requiirements will be extremely stringent and can only be met by controlling element redundancy within a distributed power system. Existing electrical systems were not developed to have both the power system and the control/sensing elements distributed and yet meet the requirements of lighting tolerance and high intensity radio frequency (HIRF). In addition, the operation of electric actuators involves high transient loading and reverse energy flows. Such phenomena were also not anticipated when power quality was specified for either 270 vdc or 400 Hertz ac power systems. This paper will expand upon the issues and discuss some of the technologies involved in their resolution.
Persistent Turing Machines as a Model of Interactive Computation

Persistent Turing Machines (PTMs) are multitape machines with a persistent worktape preserved between interactions, whose inputs and outputs are dynamically generated streams of tokens (strings). They are a minimal extension of Turing Machines (TMs) that express interactive behavior. They provide a natural model for sequential interactive computation such as single-user databases and intelligent agents. PTM behavior is characterized observationally, by input-output streams; the notions of equivalence and expressiveness for PTMs are defined relative to its behavior. Four different models of PTM behavior are examined: language-based, automaton-based, function-based, and environment-based. A number of special subclasses of PTMs are identified; several expressiveness results are obtained, both for the general class of all PTMs and for the special subclasses, proving the conjecture in [We2] that interactive computing devices are more expressive than TMs. The methods and tools for formalizing PTM computation developed in this paper can serve as a basis for a more comprehensive theory of interactive computation.
Studies on connective tissue. VI. The cytoplasm of the fibroblast

Abstract A vacuole or channel system is present in the cytoplasm of the fibroblasts of Wharton's jelly of the human umbilical cord. This system has a constant pattern as revealed by cytochemical and electron microscopic techniques. It may be associated with the production and/or storage of the connective tissue polysaccharides.
A La Recherche du Temps Perdu, or As Time Goes By: Where Does the Time Go in a Reading Tutor That Listens?

Analyzing the time allocation of students' activities in a school-deployed mixed initiative tutor can be illuminating but surprisingly tricky. We discuss some complementary methods that we have used to understand how tutoring time is spent, such as analyzing sample videotaped sessions by hand, and querying a database generated from session logs. We identify issues, methods, and lessons that may be relevant to other tutors. One theme is that iterative design of "non-tutoring" components can enhance a tutor's effectiveness, not by improved teaching, but by reducing the time wasted on non-learning activities. Another is that it is possible to relate student's time allocation to improvements in various outcome measures.
Numeric Investigation of an Axi-Symmetric Turbulent Jet

This work is focused on a numerical investigation of a turbulent axi-symmetric round jet in order to incorporate the knowledge of turbulence. Flow field analysis of a turbulent jet is one of the major research areas in recent years as turbulent jet dictates the interaction between fluid and other physical phenomena. Heat transfer, natural convection, frame propagation all depend on the behavior of turbulent jet. The mass and momentum transfer phenomena governs the flow field of the jet. A two dimensional pressure based Navier-stock solver is used to resolve the flow parameter of a turbulent round jet. Around One hundred twenty five thousand quadratic mesh elements are used for the simulation. A Mesh independency test has been done before resolving results. Characteristic flow parameters such as mean axial velocity, mean radial velocity distribution, turbulent kinetic energy, turbulent intensity, the turbulent dissipation rate are determined and presented. Similarity solution for mean axial velocity distribution and mean radial velocity distribution at different axial location are calculated and compared with experimental data. The result shows good agreement with experimental data.Copyright © 2014 by ASME
Experimental evaluation of classical automata constructions

There are several algorithms for producing the canonical DFA from a given NFA. While the theoretical complexities of these algorithms are known, there has not been a systematic empirical comparison between them. In this work we propose a probabilistic framework for testing the performance of automata-theoretic algorithms. We conduct a direct experimental comparison between Hopcroft’s and Brzozowski’s algorithms. We show that while Hopcroft’s algorithm has better overall performance, Brzozowski’s algorithm performs better for “high-density” NFA. We also consider the universality problem, which is traditionally solved explicitly via the subset construction. We propose an encoding that allows this problem to be solved symbolically via a model-checker. We compare the performance of this approach to that of the standard explicit algorithm, and show that the explicit approach performs significantly better.
Comparing instructional methods for teaching technology in education to preservice teachers using logistic regression

This analysis was completed in the context of an ongoing design project for a junior level course (Technology in Education) in the teacher preparation program in a large New England public university. We implemented a design during Fall 2003 comparing two types of instruction: problem---based learner-centered learning cycles (PBLC) and didactic direct instruction (DI), both of which reflected our previous research findings concerning best instructional practices. Analysis using Logistic Regression identified a model that differentiated the PBLC and DI approaches in areas of preservice teachers' perceived knowledge of technology integration and technology competencies, and revealed that preservice teachers who reported more favorable computer use and more knowledge of e-portfolio development were more likely to be in the PBLC approach.
Survival of Escherichia coli O157:H7 in broth and processed salami as influenced by pH, water activity, and temperature and suitability of media for its recovery.

The survival of unheated and heat-stressed (52 degrees C, 30 min) cells of Escherichia coli O157:H7 inoculated into tryptic soy broth (TSB) adjusted to various pHs (6.0, 5.4, and 4.8) with lactic acid and various water activities (a(w)s) (0.99, 0.95, and 0.90) with NaCl and incubated at 5, 20, 30, and 37 degrees C was studied. The performance of tryptic soy agar (TSA), modified sorbitol MacConkey agar (MSMA), and modified eosin methylene blue agar in supporting colony development of incubated cells was determined. Unheated cells of E. coli O157:H7 grew to population densities of 10(8) to 10(9) CFU ml-1 in TSB (pHs 6.0 and 5.4) at an a(w) of 0.99. Regardless of the pH and a(w) of TSB, survival of E. coli O157:H7 was better at 5 degrees C than at 20 or 30 degrees C. At 30 degrees C, inactivation or inhibition of growth was enhanced by reduction of the a(w) and pH. A decrease in the a(w) (0.99 to 0.90) of TSB in which the cells were heated at 52 degrees C for 30 min resulted in a 1.5-log10 reduction in the number of E. coli O157:H7 cells recovered on TSA; pH did not significantly affect the viability of cells. Recovery was significantly reduced on MSMA when cells were heated in TSB with reduced pH or a(w) for an increased length of time. With the exception of TSB (a(w), 0.90) incubated at 37 degrees C, heat-stressed cells survived for 24 h in recovery broth. TSB (a(w), 0.99) at pH 6.0 or 5.4 supported growth of E. coli O157:H7 cells at 20 or 37 degrees C, but higher numbers of heated cells survived at 5 or 20 degrees C than at 37 degrees C. The ability of unheated and heat-stressed E. coli O157:H7 cells to survive or grow as affected by the a(w) of processed salami was investigated. Decreases of about 1 to 2 log10 CFU g-1 occurred soon after inoculation of salami (pHs 4.86 and 4.63 at a(w)s of 0.95 and 0.90, respectively). Regardless of the physiological condition of the cells before inoculation into processed salami at an a(w) of either 0.95 or 0.90, decreases in populations occurred during storage at 5 or 20 degrees C for 32 days. If present at modified eosin methylene blue agar > MSMA.
Accumulation of modern sediment in Quinault submarine canyon

Abstract Twenty box cores have been studied from Quinault submarine canyon, a major pathway between the Washington continental shelf and the deep sea for silt and clay originating from the Columbia River. Sediment accumulation rates (on a 100-yr time scale) are calculated from profiles of excess 210Pb and of 137Cs. Accumulation rates decrease with increasing distance downcanyon: from 14 × 10 −2 g cm −2 yr −1 in the upper canyon (lower head) to 3 × 10 −2 g cm −2 yr −1 in the lower canyon. In the upper canyon (lower head), channel-floor areas have a higher mean accumulation rate ( 12 × 10 −2 g cm −2 yr −1 ) than channel-wall areas ( 5 × 10 −2 g cm −2 yr −1 ). The difference in accumulation rate between channel-floor and channel-wall areas indicates preferential accumulation (i.e., focusing) in topographic lows. The decrease in accumulation rate (from high rates in the channel floors of the upper canyon to low rates in the lower canyon) may be caused by progressive depletion of a nepheloid-layer source and/or may be an artifact of sediment focusing in the upper canyon. The silty clay and clayey silt accumulating in the canyon show no significant trend in grain size or clay mineralogy with depth in cores or with distance downcanyon. The lack of sorting probably results from the transport of sediment in aggregate form, with a nearly random distribution of size and mineralogy within aggregates. Quinault Canyon is accumulating approximately 5.5 × 10 5 MT of sediment yr−1. The lithogenic component (64%) accounts for 1–4% of the Columbia River discharge. Similarity of sediment-trap deposition rates (including storm events) and 210Pb accumulation rates indicates that the vertical flux is a major input of sediment to Quinault Canyon and that storms are important in the accumulation of sediment on a 100-yr time scale.
Linking the practice environment to nurses' job satisfaction through nurse-physician communication.

Purpose: To investigate direct and indirect relationships among the practice environment, nurse-physician (RN-MD) communication, and job satisfaction, as is posited in the nursing role effectiveness model (NREM). Design: Survey. Methods: Surveys were sent to a random sample of 500 hospital nurses throughout Michigan, and 332 (66%) responded. Main study instruments were the Conditions for Work Effectiveness Questionnaire-II (CWEQ-II), the Practice Environment Scale of the Nursing Work Index (PES-NWI), the ICU Nurse-Physician Questionnaire, and the Index of Work Satisfaction (IWS), Part B. Inferential statistical tests included multiple regression, t tests, and one-way analysis of variance. Findings: Practice environment (PES-NWI) and empowerment (CWEQ-II) scales explained 20% of the variance in RN-MD communication. The combination of both environment scales (PES-NWI and CWEQ-II) and RN-MD communication explained 61% of the variance in nursing job satisfaction scores. RN-MD communication was also a significant mediating variable in the relationship between structure (practice environment and empowerment scales) and outcome (nursing job satisfaction). Conclusions: Factors in the practice environment contributed both directly to nursing job satisfaction and also indirectly through RN-MD communication. Study findings showed that a practice environment favorable to nurses improved both nurses' perceptions of their communications with physicians and their job satisfaction.
Embracing and harnessing diversity in the US workforce: what have we learned?

Cultural diversity in the US includes race, ethnicity, gender, disability, age, sexual orientation, religion, and other aspects of culture. American ethnic and racial minorities currently account for 31% of the US population, and growing. Their career development issues include the barriers they regularly encounter, such as discrimination; inequitable access to resources; and language, religious, and cultural differences. Career counselors and vocational psychologists in the US have been actively studying these issues for many years and have some successes to report.
Investigation into the Origin of Magnetic Soils on the Oak Ridge Reservation, Tennessee

In 1993-1994, researchers at Oak Ridge National Laboratory collected high-resolution airborne geophysical data on the Oak Ridge Reservation, Oak Ridge, TN. The data were collected in part to address concerns about possible undocumented hazardous waste sites. Interpretation of the aeromagnetic data was complicated, however, by the discovery in remote areas of numerous small magnetic anomalies of natural origin. Magnetic susceptibility measurements of core showed that the underlying Copper Ridge Dolomite was non-magnetic. We attribute the magnetic anomalies to the presence of the ferromagnetic mineral maghemite (γ-Fe 2 O 3 ), which formed during pedogenesis of Fe-enriched colluvium that had infilled low-lying areas, including dolines. We discuss explanations offered in the literature for the formation of magnetic soils, and present evidence based on profile descriptions, thin sections, x-ray diffraction (XRD), and scanning electron microscopy (SEM), that in this case, maghemite formed either by anaerobic microbial Fe reduction followed by the formation of single-domain maghemite, or by abiological weathering and reduction of an Fe-bearing mineral followed by oxidation. Naturally occurring magnetic soils may produce magnetic anomalies similar to those characteristics of anthropogenic objects, such as buried waste drums, and complicate interpretation of airborne geophysical surveys.
Single-bundle versus double-bundle posterior cruciate ligament reconstruction

Purpose The purpose of this report is to present a systematic review of the literature to compare knee kinematics and clinical outcomes after single-bundle versus double-bundle posterior cruciate ligament reconstruction. Methods Systematic review of the literature by PubMed search, reference review, and search of Arthroscopy identified the relevant biomechanical and clinical studies. The studies were critically evaluated to determine potential advantages of single-bundle or double-bundle reconstructions in anteroposterior stability, graft tension, rotational stability, and functional outcome. Results Biomechanical comparisons evaluating anteroposterior stability described either no difference or increased stability with double-bundle reconstructions. Comparing these results is complicated by differential graft choices, tensioning techniques, and tunnel anatomy. Biomechanical studies of graft tension describe conflicting results regarding the optimal reconstruction technique. Recent studies of rotational stability suggest no advantage of double-bundle reconstruction in the setting of concomitant posterolateral corner repair but suggest a possible advantage in the setting of subtle posterolateral corner injury. Three retrospective clinical studies of single- and double-bundle reconstructions with methodologic limitations described no difference in clinical outcome. Conclusions The superiority of single-bundle or double-bundle posterior cruciate ligament reconstruction remains uncertain.
Digestion in the Rumen and Total Tract of Forage-Based Diets with Starch or Dextrose Supplements Fed to Holstein Heifers,

Abstract Three diets were fed to six cannulated heifers in a replicated 3 × 3 Latin square design. Diets were a high forage control, a high forage diet with dextrose (5.6% of DM), and a medium concentrate (39.7% of DM) diet. Diets contained 13.3% CP and 1% NaHCO 3 and were fed as a TMR twice daily. Mean ruminal pH (6.47), glucose concentration (.55m M ), and reducing sugar concentration (.64m M ) in heifers were similar across diets. Rate of orchardgrass NDF digestion in situ was faster for heifers fed the dextrose than for those fed the medium concentrate diet, but both were similar to that for heifers fed the control diet. Heifers fed the medium concentrate and dextrose diets had faster ruminal particulate fractional passage rates than those fed the control diet. True ruminal and apparent total tract digestion of OM and NDF were similar among diets, but ruminal NDF digestion tended to be higher with the control than with the medium concentrate diet. Total NAN and bacterial N flow to the duodenum and efficiency of bacterial protein synthesis in the rumen were greater with the medium concentrate diet than with the control and dextrose diets. The results were consistent with others that demonstrated that factors related to nonstructural carbohydrates in the diet other than just low ruminal pH affect ruminal fiber digestion; however, these results were not as strong as those of our previous in vitro work.
Electrothermal atomic absorption spectrometric determination of aluminum in blood serum

Abstract An aerosol-generating device is used for sample application. Precision ranges from 2.5 to 8.0% and recoveries of 30 and 100 μg l-1 added to each of five samples ranged from 95 to 105%. Correlation with a slightly different method gave a least-squares fit of y = 1.02x – 1.35 μg l-1. The technique described is satisfactory for studying aluminum toxicity in dialysis encephalopathy and Alzheimer's Disease.
Optical pulses in atmospheric turbulence

Rytov’s method is generalized so that it can be applied to the time-dependent wave equation. The method is used to obtain an expression for a pulsed spherical wave that has propagated through atmospheric turbulence. The expression contains two terms. One term represents scattering by refractive-index inhomogeneities located on a direct line between the transmitter and receiver. The other term arises from the time-varying dimensions of the scattering volume of the pulsed wave and represents scattering by inhomogencities located on the surface of a prolate spheroid. Under appropriate conditions, the surface scattering can be neglected, so that if the pulse shape does not change significantly over times on the order of the period of the carrier frequency, the pulse shape will be preserved after transmission through the turbulence. In this case, the fluctuations depend upon only the carrier frequency. The statistics of the direct-line term are shown to be identical to the statistics for the monochromatic spherical wave. The surface and direct-line terms remain correlated for only a very short period during the beginning of the pulse.
Family functioning, peer influence, and media influence as predictors of bulimic behavior

One hundred and twenty undergraduate women students reported their height and weight and completed the Eating Disorder Questionnaire (EDQ), the Eysenck Personality Inventory (EPI), the Beck Depression Inventory (BDI), the Family Assessment Device (FAD), the Body Shape Questionnaire (BSQ), the Body Image Assessment (BIA), and measures of peer and media influence. Family functioning was shown to be a poor predictor of bulimic behavior, whereas peer influence was a significant predictor. Media influence interacted with body dysphoria to increase the likelihood of bulimic behavior. The BSQ was a better predictor of bulimic behavior than the BIA, suggesting that students' responses to a measure that asks questions about specific areas of the body may reflect their feelings of body dysphoria more accurately than a measure that relies on a generalized silhouette.
Magnetic field induced instability on an aligned nematic solution of a rodlike polymer

Abstract The reorientation of an initially well aligned nematic rodlike solution of the rodlike poly(1,4-phenylene-2,6-benzobisthiazole), PBT, in an external magnetic field in the sample plane is studied. For angle β between the magnetic field H and the initial director n less than 45 degrees, the reorientation occurs by a homogeneous twist distortion of the director field, permitting assessment of the Frank elastic constant KT and the Leslie viscosity ηT. For larger β, the reorientation is nonhomogeneous, with a component of the distortion out of the sample plane, resulting in a phase-grating, made manifest by its focusing effects for transmitted light.
Screen-printed ultramicroelectrode arrays for on-site stripping measurements of trace metals

Abstract The properties and advantages of mercury-coated screen-printed electrode arrays for on-site stripping analysis of trace metals are described. These disposable composite electrodes are fabricated by a combination of thick-film printing and laser machining technologies, and offer a stripping performance comparable with that of traditional stripping electrodes. Scanning electron microscopy illustrates the attractive microdisk and interelectrode dimensions, which offer a non-linear diffusional flux during long stripping experiments. The stripping performance is not compromised by placing non-deaerated/quiescent sample drops on the strip, as desired for field monitoring of trace metals. Various experimental variables have been optimized to yield low detection limits (e.g. 0.1 μg/l lead for 4 min deposition) and good precision (e.g. relative standard deviation of 4.7% for ten repetitive measurements). The applicability to assays of drinking water and wine is illustrated.
Team Building: An Anthropologist, An Occupational Therapist, and the Story of a Pediatric Multiple Sclerosis Community

Although Multiple Sclerosis (MS), a chronic condition affecting the immune and nervous systems, is usually diagnosed in young adulthood, it has become possible, in recent years, to detect and diagnosis this condition in children aged six or younger. Up to five percent (5%) of MS diagnoses now take place prior to the age of 18 with estimates ranging from 10,000-15,000 children having this condition in the United States (Krupp et al. 2007). This newly identified childhood disability offers a unique opportunity for a cultural anthropologist and an occupational therapist to use a community-based disability studies research strategy for facilitating community and support systems that assist children and their families in coping with the challenges of MS. These challenges are intimidating for most families (MacAllister et al. 2007). Pediatric clinicians and school professionals may be unaware that pediatric MS exists and unprepared to assist children with this diagnosis. Neurologists specializing in MS may have...
Hα (Balmer) spectral profiles obtained from H2 rf plasma discharges studied by intracavity laser spectroscopy

Hα (Balmer) spectral absorption profiles are obtained for 13.56 MHz rf discharges of hydrogen at pressures from 25 m Torr to 3.0 Torr. The Hα transitions are monitored by intracavity laser spectroscopy using high spectral resolution. Spatially resolved concentrations of atomic hydrogen in the n=2 state (H*) are measured across the region between the power and ground electrode. The H* density distribution follows the glow space. The electron densities are (1–3) × 1010 cm−3. The profiles indicate that the 2S12 and 2P12 states are populated first in the discharges. The system is not in thermodynamic equilibrium but comes closer to it at pressures greater than 500 m Torr.
Production of Cosmic Radiation at the Sun

A calculation is made of the average production rate of 4-Bv cosmic-ray particles at the sun. The calculation is based upon the recent experimental evidence that the frequently occurring small solar flares produce temporary increases of neutron intensity in suitably located neutron pile detectors. This production rate, averaged over the 11-year solar cycle, is somewhat in excess of the absorption rate of 4-Bv particles by bodies in the solar system. If the production at the sun is to account for most of the observed cosmic radiation intensity, a trapping magnetic field is required. Limits on the size of such a trapping volume are estimated by considering the limits of cosmic-ray lifetime; the requirement of a high degree of radiation isotropy at the earth is satisfied. The existence of high-energy particles in the cosmic radiation imposes the principal difficulty for any solar origin hypothesis.
Factor structure and stability of the Anxiety Sensitivity Index in a longitudinal study of anxiety disorder patients.

The past decade witnessed considerable debate over the factor structure of the Anxiety Sensitivity Index (ASI), with an eventual consensus emerging that supported a hierarchically organized factor structure. The present study attempted to replicate and examine the overall stability and utility of the hierarchical ASI factor pattern using a large sample of outpatients participating in an ongoing longitudinal study of anxiety disorders. Results supported a hierarchical factor structure for the ASI consisting of three lower-order factors measuring physical concerns, mental incapacitation concerns, and social concerns, all of which loaded significantly on a single second-order factor. Correlational analyses show good test–retest reliability and consistent patterns of intercorrelation for these factor-derived subscales across a 10-month time frame. Additional analyses provide support for the discriminant validity of the ASI subscales with regard to individuals with specific anxiety disorders. The theoretical implications of these findings for future evaluations of anxiety sensitivity are discussed.
Coping with Interpersonal Stress and Psychosocial Health Among Children and Adolescents: A Meta-Analysis

This meta-analysis examines the relationship between active coping and psychosocial health among youth. Results from 40 studies of coping with interpersonal stress were synthesized using a random-effects model. Four areas of psychosocial functioning were examined: externalizing and internalizing behavior problems, social competence, and academic performance. The magnitude of the relationship between active coping and psychosocial functioning was small, with correlations ranging from 0.02 for internalizing behavior to 0.12 for academic performance. Mean effects were moderated by stressor controllability: youth who used active coping in response to controllable stressors had fewer externalizing problems and higher social competence, as compared to those who used active coping in response to uncontrollable stressors. Implications for primary prevention programs and directions for future research on child and adolescent coping are discussed.
Microbial mineralization of VC and DCE under different terminal electron accepting conditions.

Abstract Production of14CO2from [1,2-14C] dichloroethene (DCE) or [1,2-14C] vinyl chloride (VC) was quantified in aquifer and stream-bed sediment microcosms to evaluate the potential for microbial mineralization as a pathway for DCE and VC biodegradation under aerobic, Fe(III)-reducing, SO4-reducing, and methanogenic conditions. Mineralization of [1,2-14C] DCE and [1,2-14C] VC to14CO2decreased under increasingly reducing conditions, but significant mineralization was observed for both sediments even under anaerobic conditions. VC mineralization decreased in the order of aerobic > Fe(III)-reducing > SO4-reducing > methanogenic conditions. For both sediments, VC mineralization was greater than DCE mineralization under all electron-accepting conditions examined. For both sediments, DCE mineralization was at least two times greater under aerobic conditions than under anaerobic conditions. Although significant microbial mineralization of DCE was observed under anaerobic conditions, recovery of14CO2did not differ substantially between anaerobic treatments.
Band structure, magneto-transport, and magneto-optical properties of InAs-Ga 1−x In x Sb superlattices

We have theoretically and experimentally investigated the electronic properties of InAs-Ga1-xInxSb superlattices. It is found that a strong repulsion between the El and HI bands in superlattices with thin Ga1-xInxSb layers leads to dispersion relations that closely resemble those in HgTe-CdTe superlattices. Temperature-dependent magneto-transport and magneto-optical measurements on samples with a range of InAs layer thicknesses confirm several of the theoretically predicted consequences, e.g., the coexistence of two electron species in semimetallic superlattices and a very light electron cyctron mass in narrow-gap semiconducting samples. The electron mobility is found to be dominated by interface roughness scattering under nearly all conditions of interest. Implications for this system as an infrared detector material are discussed.
Dynamics of lysosomal elements in pulmonary alveolar macrophages: I. The postactivation lysosomal cycle

Lavaged alveolar macrophages of mice were examined by light and electron microscopy primarily using cytochemical reactions for lysosomal enzymes. Among several methods tried, the Reed and Bennett procedure for N-acetyl-β-glucosaminidase (J. Histochem. Cytochem., 23:752–757 (1975)) was preferred for use in smears and the Gomori acid phosphatase method for ultrastructural study. Prior to examination, some mice were exposed to an aerosol of finely divided iron oxide for 1–3 hours at particle concentrations of 80–290 mg/m3, others breathing clean air provided macrophages for comparison. Both exposed and unexposed macrophage populations were composed of a similar range of subtypes differing in cytological appearance and enzymic activity. The exposed populations tended to contain a higher proportion of strongly reactive cells, notably of a kind possessing many elongate lysosomes; consequently, it appeared that many cells in these populations were substantially engaged in synthesizing lysosomes. Based on this material, the cycle of production was reconstructed. This is divisible into five natural stages, defined primarily by the intracellular distribution of lysosomal enzyme activity and to a lesser extent by other cytological criteria. Commencing in immature cells, where the predominant localization of acid phosphatase activity in the Golgi apparatus and a few rounded lysosomes (Stage 1), the cycle continues through a period dominated by extensive growth of the granular endoplasmic reticulum (Stage 2). With the appearance of a crop of elongate or lumbricoid lysosomes, the predominate locus of acid phosphatase activity shifts from the Golgi apparatus to these bodies (Stage 3). Thereafter, they often are seen together with an increased number of large rounded lysosomes (Stage 4), but in other cells only the latter are to be found (Stage 5). This lysosomal cycle operates in cells showing other signs of an aroused metabolism, and it appears not to be closely tied to the mitotic cycle. The nascent lumbricoid lysosomes seem to be formed at some distance from the Golgi apparatus, wheras the lysosomes produced by more quiescent cells often lie in close relationship to that organelle.
Effect of coffee feeding on the duodenal transport and bile excretion of calcium in the rat

Abstract Caffeine administration increases endogenous fecal calcium and urinary calcium excretion resulting in a deterioration of calcium balance. The aim of the current study was to investigate the effect of coffee feeding on the intestinal transport of calcium and the mechanism of enhancement of endogenous calcium secretion. A group of rats were fed a diet containing 4% instant coffee and their calcium metabolism was compared to a control group fed the same diet with cellulose replacing the instant coffee. The results of the calcium balance study showed that 3 weeks of coffee consumption caused an increase in endogenous fecal calcium and urinary calcium excretion without a change in the absorption coefficient of calcium. We used an in vivo ligated loop technique to fractionate the calcium of the bile from that of the mucosal efflux and pancreatic secretions. The results indicated that the enhancement of endogenous calcium secretion into the duodenal lumen was from an increase in bile secretion and in mucosal efflux. When the bile flow rate was measured by direct cannulation of the bile duct, we were able to demonstrate that chronic coffee feeding resulted in a 45% increase in the bile flow rate without a change in the calcium concentration in the bile fluid.
After Finitude: An Essay on the Necessity of Contingency. By Quentin Meillassoux

After Finitude: An Essay on the Necessity of Contingency. By Quentin Meillassoux. Translated by Ray Brassler (London: Continuum, 2009), viii + 148 pp. £12.99 paper. This enormously exciting book fo...
Genome-scale analysis of gene function in the hydrogenotrophic methanogenic archaeon Methanococcus maripaludis

A comprehensive whole-genome analysis of gene function by transposon mutagenesis and deep sequencing methodology has been implemented successfully in a representative of the Archaea domain. Libraries of transposon mutants were generated for the hydrogenotrophic, methanogenic archaeon Methanococcus maripaludis S2 using a derivative of the Tn5 transposon. About 89,000 unique insertions were mapped to the genome, which allowed for the classification of 526 genes or about 30% of the genome as possibly essential or strongly advantageous for growth in rich medium. Many of these genes were homologous to eukaryotic genes that encode fundamental processes in replication, transcription, and translation, providing direct evidence for their importance in Archaea. Some genes classified as possibly essential were unique to the archaeal or methanococcal lineages, such as that encoding DNA polymerase PolD. In contrast, the archaeal homolog to the gene encoding DNA polymerase B was not essential for growth, a conclusion confirmed by construction of an independent deletion mutation. Thus PolD, and not PolB, likely plays a fundamental role in DNA replication in methanococci. Similarly, 121 hypothetical ORFs were classified as possibly essential and likely play fundamental roles in methanococcal information processing or metabolism that are not established outside this group of prokaryotes.
Cytoplasmic and cytoskeletal regulation of glutamate receptor channels

Abstract The regulation of glutamate receptor channels by intracellular messengers is an important component in the plasticity of central excitatory synapses. This review summarizes recent evidence demonstrating that phosphorylation, intracellular calcium and interactions with cytoskeletal proteins can dramatically influence the properties of N-methyl-D-aspartate (NMDA) and α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptor channels. Kinases and intracellular calcium exert their action either directly on glutamate receptor channel subunits or indirectly via regulatory proteins or second messenger cascades. Recent evidence also suggests that interactions with cytoskeletal proteins play a dynamic role in regulating the gating of glutamate receptor channels. These studies provide tantalizing evidence for a complex set of regulatory interactions in the postsynaptic density.
Derivatives of the red-violet cluster of copper and penicillamine prepared by mixed ligand formation reactions or direct additions

Mixed ligand clusters of the type Cu(I)8Cu(II)6L'(n)L(12−n)Cl are easily distinguished by zone electrophoresis if ligands L and L' differ in formal charge. Approximately random species distributions were observed when L was penicillamine and L' a related ligand lacking the negative charge of a carboxylate group, provided the L'/L molar ratio was less than 19 in the reaction mixture. Depending on the choice of L or L', it should be possible to prepare clusters with a variety of pendant groups. The cluster containing only penicillamine apparently forms addition products with carbodiimides and aziridines based on reactions involving the cluster's peripheral carboxylate groups.
Non-steroidal anti-inflammatory drugs and colorectal cancer prevention

Colorectal cancer is the second leading cause of cancer deaths in the United States. Currently, the most effective strategy available for colon cancer prevention is endoscopic screening, with polypectomy or surgical resection for advanced lesions. This intervention carries with it many concerns regarding cost, patient acceptance, and the growing burden of surveillance colonoscopies for patients with polyps. Further improvements in the understanding of the multistep model of colorectal carcinogenesis will probably lead to the development of other primary and secondary prevention strategies. Data obtained from animal and epidemiological studies and most recently from randomised, placebo controlled trials, suggest that non-steroidal anti-inflammatory drugs may prove effective chemopreventive agents in different groups of people, from patients with familial adenomatous polyposis to those with sporadic adenomas.
Gibbs free energy of adsorption for biomolecules in ion-exchange systems

The Gibbs free energy of adsorption (delta G0ads) was estimated for several amino acids, peptides and proteins in a cation-exchange system. Using the steric mass action formalism that describes biomolecular adsorption in ion-exchange systems, the delta G0ads was chromatographically determined under infinitely dilute conditions. The delta G0ads measured for seven globular proteins ranged from -5.7 to -13.9 kcal/mol. The average bond energy (defined as delta G0ads divided by the number of bonds formed between the protein and the surface) for these proteins varied from -1.1 to -1.7 kcal/mol. These bond energies were found to be comparable to the bond energies for lysine and arginine (-1.1 and -1.5 kcal/mol, respectively), the amino acids which primarily contribute to the cation-exchange of proteins. In contrast, an elevated average bond energy of -2.6 kcal/mol was observed for two peptides and protamine (a polypeptide) suggesting that synergistic binding may play a role for unstructured macromolecules, but not for globular proteins.
Promoting Student Cognitive Development in Counselor Preparation: A Proposed Expanded Role for Faculty Advisers

The development of cognitively complex counselors has been identified as an important component of counselor education. However, there are no models to provide direction for programs to systematically promote student cognitive growth over the entire course of their graduate education. In many counseling programs, the faculty adviser is the one professor who has interactions with a student from admission through graduation and, thus, could serve an important role in coordinating efforts to facilitate student cognitive development. Toward that end, the authors propose a structured advising model to assist faculty advisers in facilitating the cognitive growth of their advisees.
A simulation approach to recreation planning (A case of changing quality)

Conventional demand based approaches to recreational economics are reviewed and found unsuitable for analyzing the effects of changes of the quality of recreation. An alternative approach using a simulation model is proposed, which allows the use of both quantitative data and subjective input on the qualitative effects. The critical economic variables are found to be fishing recreation visitor days and investment in recreational facilities at the Salton Sea, California.
Native Recombinant Cyclophilins A, B, and C Degrade DNA Independently of Peptidylprolyl cis-trans-Isomerase Activity POTENTIAL ROLES OF CYCLOPHILINS IN APOPTOSIS

Previous work in our laboratory (Montague, J., Gaido, M., Frye, C., and Cidlowski, J. (1994) J. Biol. Chem. 269, 18877-18880) has shown that human recombinant cyclophilins A, B, and C have sequence homology with the apoptotic nuclease NUC18 and that denatured cyclophilins can degrade DNA. We have now evaluated the nucleolytic activity of recombinant cyclophilins under native conditions. We show that nuclease activity inherent to cyclophilins is distinct from cis-trans-peptidylprolyl isomerase activity and is similar to that described for apoptotic nucleases. Cyclophilin nucleolytic activity is stimulated by Ca2+ and/or Mg2+, with a combination of the two being optimal for cyclophilins A and B. Mg2+ alone is sufficient for cyclophilin C nuclease activity. pH optimums are in the range of pH 7.5-9.5. Cyclophilins can degrade both single-stranded and double-stranded DNA. Additionally, cyclophilins produce 3′-OH termini in linear double-stranded substrates, suggesting the cuts produced are similar to those of apoptotic cells. Cyclophilins also display endonucleolytic activity, demonstrated by their ability to degrade supercoiled DNA. In the absence of ions, cyclophilins bind linearized DNA. When added to nuclei from nonapoptotic cells, cyclophilin C induces 50-kilobase pair DNA fragmentation but not internucleosomal fragmentation. Together, these data suggest that cyclophilins are involved in degradation of the genome during apoptosis.
Redox reactivity of cerium oxide nanoparticles against dopamine

Abstract The interaction between dopamine and the redox active cerium oxide nanoparticles, or nanoceria was studied using a suite of spectroscopic and surface characterization methods. Changes in the chemical reactivity and concentration of dopamine upon exposure to nanoceria was assessed in aqueous solutions and a human physiological fluid – human serum. The results indicate strong attachment of dopamine to the nanoparticle surface through oxidation followed by chemisorption of the oxidative product with formation of a charge transfer complex. Such oxidation/surface adsorption processes between nanoceria and dopamine lead to a reduction of the concentration of free dopamine in aqueous environments. These findings suggest that the redox reactivity of nanoceria may alter dopamine levels in biological systems exposed to these particles and indicate the need for a comprehensive assessment of the potential neurological consequences that might result from intended or unintended exposure to these particles.
Subtalar arthrodesis with the combined Batchelor–Grice technique

Abstract Eight patients (13ft) with progressive neuromuscular planovalgus foot deformity, underwent an extraarticular subtalar arthrodesis with the combined Batchelor–Grice procedure. All patients were ambulant and received conservative treatment with braces and special orthopaedic shoes prior to operation. Postoperatively the feet were immobilized in short casts for six weeks. Evaluation was based on the appearance of the feet, the clinical symptoms and X-ray measurements. Solid fusion and sustained correction, took place in all feet. Foot appearance and mobility of the patients were improved, while preoperative complaints were reduced. The gap at the graft donor site was bridged with new bone in all cases.
Microarray analysis of RhoC-transformed mammary epithelial cells suggests molecular mechanisms of inflammatory breast cancer

Microarray analysis of RhoC-transformed mammary epithelial cells suggests molecular mechanisms of inflammatory breast cancer
Integration of dynamic voltage scaling and soft real-time scheduling for open mobile systems

Battery-powered mobile devices are becoming increasingly important computing platforms, which require low energy consumption while meeting the resource demands of a dynamic application workload. Most proposed dynamic voltage scaling (DVS) algorithms, targeting either best-effort or hard real-time systems, however, cannot be directly applied to such open mobile systems. This paper presents a framework to integrate DVS into soft real-time (SRT) scheduling for open mobile systems, achieving energy saving of DVS while preserving resource guarantees of SRT scheduling. The integrated framework makes three major contributions. First, multimedia applications reserve resource based on their average resource usage, without the knowledge of worst-case execution time, which is difficult to estimate in an open mobile environment. Second, the SRT scheduling ensures the correctness of reservation admission and enforcement in a variable speed context. Finally, the DVS manager reduces the processor energy consumption by utilizing the unallocated resource, reclaiming the allocated but unused resource, or avoiding the unused resource. Our extensive simulation results demonstrate that our framework is able to save 4% to 32% energy while slightly affecting application performance.
Mechanical behavior of diffusion-bonded bicrystals of boron-doped Ni3Al

Abstract We report the results of mechanical tests on a Σ5 (210) [001] symmetric tilt boundary in a diffusion-bonded artificial bicrystal of boron-doped Ni 0.76 Al 0.24 . We find that heat treatments designed to induce boron segregation appear to strengthen the boundary, whereas heat treatments designed to discourage segregation weaken it. However, the bonding of the bicrystal is non-uniform, and this introduces significant uncertainty into our data because of our very small sample size (six). Nevertheless, we conclude that such artificial bicrystals offer considerable flexibility in the study of the effects of orientation on boundary strength and solute segregation in nickel aluminides, as well as in other metals and intermetallics.
Release from herbivory does not confer invasion success for Eugenia uniflora in Florida

One of the most commonly cited hypotheses explaining invasion success is the enemy release hypothesis (ERH), which maintains that populations are regulated by coevolved natural enemies where they are native but are relieved of this pressure in the new range. However, the role of resident enemies in plant invasion remains unresolved. We conducted a field experiment to test predictions of the ERH empirically using a system of native, introduced invasive, and introduced non-invasive Eugenia congeners in south Florida. Such experiments are rarely undertaken but are particularly informative in tests of the ERH, as they simultaneously identify factors allowing invasive species to replace natives and traits determining why most introduced species are unsuccessful invaders. We excluded insect herbivores from seedlings of Eugenia congeners where the native and invasive Eugenia co-occur, and compared how herbivore exclusion affected foliar damage, growth, and survival. We found no evidence to support the ERH in this system, instead finding that the invasive E. uniflora sustained significantly more damage than the native and introduced species. Interestingly, E. uniflora performed better than, or as well as, its congeners in terms of growth and survival, in spite of higher damage incidence. Further, although herbivore exclusion positively influenced Eugenia seedling survival, there were few differences among species and no patterns in regard to invasion status or origin. We conclude that the ability of E. uniflora to outperform its native and introduced non-invasive congeners, and not release from insect herbivores, contributes to its success as an invader in Florida.
Requirements for a Revolution in Automotive Technology

The history of automotive technology contains many cases in which a new technology completely replaces its predecessor. The universal use of diode-rectified alternators in place of brush-commutated generators is one example. The conditions under which such a revolution may occur will be considered. A number of prospective new automotive technologies, all involving the use of electromagnetic and/or power electronic systems, will be examined for their potential to become a universal technology.