cssi/SciSciGPT-SciSciNet huggingface dataset:
Diabetic dilemma in dentistry

The evidence is clear that diabetes mellitus is not a specific disease. Additionally, the information is available to suggest that the definition of periodontal disease leaves much to be desired. Hence, it follows that it is impossible to equate these two poorly defined entities. A more realistic approach suggests that one or more periodontal parameters be examined in the light of carbohydrate metabolism. Data have been offered to suggest that gingival state is modified following prophylaxis or orthodontic banding with and without consideration given to toothbrushing habits and irrespective of host state. Conversely, evidence has been presented to indicate that gingival state is altered following dietary change (the addition or elimination of refined carbohydrates) with and without consideration given to prophylaxis and/or toothbrushing habits. Next, material was offered to indicate that carbohydrate metabolism plays a role in gingival response to prophylaxis with and without attention given to toothbrushing. Lastly, there are limited but interesting observations which point to carbohydrate metabolism as a factor in oral hygiene when defined as the state of cleanliness. It is hoped that, viewing the problems in this ecologic frame (fig. 35), will help resolve the diabetic dilemma in dentistry.
Understanding African Conflicts: Theoretical, Historical, and Contemporary Perspectives

On the eve of the first decade of the twenty-first century?and some fifty years after independence?many African states continue to be plagued by ethnoregional conflict, while a number of others are barely emerging from decades of devastating civil wars. Peace and security?essential prerequisites for democracy and development?continue to elude far too many African countries. Building upon the pioneering work of Christopher Clapham in African Guerillas (James Currey, 1998), Morten B0?s, Kevin Dunn, and their nine contributors?including Clapham, author of the concluding chap ter?revisit the analysis of African guerilla movements. Rejecting single-fac tor explanations (such as greed, competition over resources, and cultural conflict), the editors argue for "a more nuanced, holistic approach that is historically grounded and integrates multiple levels of analysis, from the local and national to the regional and global" (3). Further inspired by the groundbreaking research of the anthropologist Paul Richards (No Peace, No War, James Currey, 2005), B0?s and Dunn believe that "African insurgen cies are best understood as rational responses to the composition of African states and their polities" (4); and they approach war as "a social drama over
Pyromagnetic study of the spin-reorientation transition in YbFe O 3

A single-crystal sample of ytterbium orthoferrite is investigated using a pyromagnetic detection method from 4.2 to 20 \ifmmode^\circ\else\textdegree\fi{}K. The existence of two second-order phase transitions at either end of the spin reorientation in YbFe${\mathrm{O}}_{3}$ is obvious. Quadrature detection is used to measure both the broadened transition response of the crystal axis parallel to an applied magnetic field and the shifted off-axis response. An estimation of the lower transition temperature for zero magnetic field is inferred from measurements to be ${T}_{1}=6.31$ \ifmmode^\circ\else\textdegree\fi{}K and the upper transition at ${T}_{2}=7.59$ \ifmmode^\circ\else\textdegree\fi{}K. The field slopes of the off-axis transitions are constant for fields greater than 1 kOe where $\frac{d{T}_{1}}{d{H}_{a}}=0.083$ \ifmmode^\circ\else\textdegree\fi{}K/kOe, $\frac{d{T}_{2}}{d{H}_{c}}=0.066$ \ifmmode^\circ\else\textdegree\fi{}K/kOe. A phenomenological description due to Horner and Varma and a microscopic model presented by Levinson et al. are reviewed. The pyromagnetic detection method is presented and output functions for a spin-reorientation transition are calculated on the basis of a modified Levinson model. The measured signals are in qualitative agreement with the calculated response functions. Expressions for the second- and fourth-order magnetic-ansisotropy constants in the Landau free-energy expression for displacive phase transitions are calculated from experimental data. Finally, the peak pyromagnetic response of YbFe${\mathrm{O}}_{3}$, using the quadrature detection method, was more than 300 times that of Gd at room temperature. This result suggests the possibility of more sensitive infrared-radiation detectors using either room-temperature reorientations or a quadrature pyromagnetic detection method on existing materials.
Snacking patterns among 1,800 adults and children

Abstract Objective To study snacking behavior, including frequency, time of day, location, and qualities sought in snack choices. Design A survey questionnaire was designed for use by trained telephone interviewers to interview adults and for self-administration by students in the fifth and sixth grades. Setting A national random sample was drawn of 1,510 adults, and a nonrandom sample was drawn of 290 fifth and sixth graders attending schools in four states. Subjects Adults were randomly selected by a computerized telephone directory system from 48 states (Hawaii and Alaska were excluded). The five schools surveyed were selected to represent a major inner city (Atlanta, Ga), a suburban area (Englewood, NJ), a midsize city (two schools in St Louis, Mo), and a rural area (Hickman, Calif). Results The majority of children in all age groups snacked at least once daily. Morning was the least common and afternoon was the most common time for snacking. Almost all snacking occurred at home. In the selection of snacks, taste outranked nutrition as the most important characteristic of a snack. Fruits were popular with all age groups, but overall they were chosen less often at snacktime than foods from other categories. Applications Snacking should be targeed with specific nutrition education messages that address the influences of time of day, location, and qualities of foods on snack choices.
Tactics of manipulation.

Manipulation is one means by which environments are altered to correspond to characteristi cs of individuals. We conducted two studies to identify the manipulation tactics that people use lo elicit and terminate the actions of others. Factor analyses of four instruments revealed six types of tactics: charm, silent treatment, coercion, reason, regression, and debasement. Tactics of manipulation showed strong individual difference consistency across contexts. The charm tactic, however, was used more frequently for behavioral elicitation, whereas the coercion and silent treatment tactics were used more frequently for behavioral termination. Manipulation tactics covaried significantly across self-based and observer-based data sources with personality scales of Neuroticism, Extraversion. Ambitious-Lazy, Arrogant-Unassuming, Quarrelsome-Agreeable, and Calculating and with characteristics of subjects' social environments. We draw implications for an interactionis t framework of person-environment correspondence, for an expansion of the taxonomic task thai faces personality psychology, and for identifying links between personality and other scientific disciplines.
Reengineering of Nutritional Screening Process

Abstract A performance improvement team was established to improve the effectiveness of the nutritional screening process. Data was collected using time studies of the dietetic technician, interaction with the dietitian, and the number of patients screened and educated in a week. This data showed inefficient personnel and resource use as well as a lack of continuity of care. As a result, 24 hour nutrition screening by ward nursing staff was further developed and levels of care based on a point system were established in order to prioritize patients. This allowed immediate documentation of the nutrition plan in the medical record. Food preferences, diet changes, poor food intake, and education of patient and family were also addressed in a timely manner. The new screening plan enables direction and action without delay which improves communication between all the members of the health care team. The dietetic technician spends more time initially screening patients and educating on basic diets and drug/nutrient interactions rather than shuffling papers back and forth. High risk patients are identified early and referred to the dietitian for nutritional assessment and intervention. Low risk patients are rescreened by the dietetic technician in three to five days and reevaluated if their level of care has changed. This enables the dietitian to intervene quickly and provide follow-up for the high risk patient. The process improvement team has made significant progress in resource utilization, quality of life for staff and quality of care for the patient.
Commonalities in the neurobiology between autism and fragile X

There is a close association between autism and fragile X syndrome (FXS) with 30% of males with FXS having autism and 2 to 7% of children with autism having the fragile X mutation. The protein that is missing or deficient in FXS, FMRP, is an RNA binding and transport protein which regulates the translation of many messages important for synaptic plasticity. Typically FMRP inhibits the translation of these messages, such that protein production increases when FMRP is absent. Some of these proteins are known to also cause autism when they are mutated including neuroligin 3 and 4 and the SHANK protein. Therefore, when FMRP is missing there is dysregulation of other proteins that are known to cause autism. FMRP is an important inhibitor of protein production in the metabotropic glutamate receptor 5 pathway (mGluR5) which leads to long term depression (LTD) or the weakening of synaptic connections. Therefore, when FMRP is missing there is enhanced mGluR5 activity leading to enhanced LTD and weak or immature synaptic connections. The use of mGluR5 antagonists to reverse the LTD in the animal models of FXS has led to reversal of the learning, behaviour and dendritic spine abnormalities in these animals. There are now initial studies taking place in humans regarding the use of mGluR5 antagonists to improve behaviour and cognition in FXS. It is likely that these mGluR5 antagonists will also be helpful in a subgroup of patients with non fragile X autism who have similar problems with hyperactivity, hyperarousal and anxiety to those seen in FXS. A second cause of autism is the fragile X premutation but this mechanism of involvement is related to RNA toxicity which perhaps stimulates neuroimmune problems and may mimic other causes of autism. Neurons with the premutation are more vulnerable to environmental toxicity and oxidative stress leading to early cell death.
Synthesis and processing in vivo of the novel mouse thyrotropin beta-presubunit that contains an NH2-terminal extension sequence.

Expression of the single mouse TSH beta gene gives rise to multiple mRNAs, and we have previously shown that in vitro, one of these mRNAs gives rise to a novel TSH beta-presubunit due to initiation of translation at an in-frame start site unique to this mRNA which is up-stream of the normal start site. The novel presubunit contains a 17-amino acid NH2-terminal extension sequence compared to the normal presubunit. Although this extension sequence does not have the characteristics of a normal signal sequence, the novel TSH beta-presubunit was processed in vitro by microsomal membranes. In this study we have examined the translation product of this mRNA in intact cells and whether in vivo it gives rise to a processed secreted TSH beta-subunit that has an NH2-terminal sequence different from that of the established TSH beta-subunit. Firstly, mRNAs encoding alpha-presubunit and either the normal or novel TSH beta-presubunit were microinjected into Xenopus oocytes, and it was found that immunoprecipitable TSH d...
Spreadsheet driven web applications

Creating and publishing read-write-compute web applications requires programming skills beyond what most end users possess. But many end users know how to make spreadsheets that act as simple information management applications, some even with computation. We present a system for creating basic web applications using such spreadsheets in place of a server and using HTML to describe the client UI. Authors connect the two by placing spreadsheet references inside HTML attributes. Data computation is provided by spreadsheet formulas. The result is a reactive read-write-compute web page without a single line of Javascript code. Nearly all of the fifteen HTML novices we studied were able to connect HTML to spreadsheets using our method with minimal instruction. We draw conclusions from their experience and discuss future extensions to this programming model.
GaInNAsSb/GaAs vertical cavity surface emitting lasers at 1534 nm

Electrically pumped, C-band vertical cavity surface emitting lasers (VCSELs) grown on GaAs are reported for the first time. The VCSELs employed three GaInNAsSb quantum wells separated by GaNAs barriers. Pulsed lasing was observed at 1534 nm, in the ITU C-band, when cooled. These lasers exhibit the longest wavelength reported to date for electrically pumped VCSELs grown on GaAs substrates.
Crystal structures and optical properties of new quaternary strontium europium aluminate luminescent nanoribbons

We report the synthesis and characterization of three series of new quaternary strontium europium aluminate (Sr–Eu–Al–O; SEAO) luminescent nanoribbons that show blue, green, and yellow luminescence from localized Eu2+ luminescent centers. These three series of SEAO nanoribbons are: blue luminescent, tetragonal Sr1−xEuxAl6O10 (0 < x < 1) (b-SEAO), green luminescent, monoclinic Sr1−xEuxAl2O4 (0 < x < 1) (g-SEAO), and yellow luminescent, hexagonal Sr1−xEuxAl2O4 (0 < x < 1) (y-SEAO). Among these three series of SEAO nanoribbons, the b-SEAOs and y-SEAOs are new compounds that have not been reported before. The crystal structures of the SEAO nanoribbons were comprehensively studied using various synchrotron X-ray diffraction techniques and the effects of crystal structures on materials' luminescence properties were investigated. These one-dimensional SEAO luminescent nanoribbons can function as both light generators and waveguides, and thus have promising potential as the building blocks in miniaturized photonic circuitry.
CHARGE-DENSITY-WAVE ORDERING IN HALF-FILLED HIGH LANDAU LEVELS

We report on numerical studies of two-dimensional electron systems in the presence of a perpendicular magnetic field, with a high Landau level index (N > 1) half filled by electrons. Strong and sharp peaks are found in the wave vector dependence of both static density susceptibility and equal-time density-density correlation function, in finite-size systems with up to twelve electrons. Qualitatively different from partially filled lowest (N=0) Landau level, these results are suggestive of a tendency toward charge density wave ordering in these systems. The ordering wave vector is found to decrease with increasing N.
SysML and UML 2 support for activity modeling

This article describes activity modeling as specified by the Systems Modeling Language (as specified by the SysML Merge Team, , February 2006) and the finalization of the Unified Modeling Language version 2 (UML 2). It reviews and updates an earlier proposed alignment between Enhanced Functional Flow Block Diagrams (EFFBD), UML 2 Activities, and requirements developed by the International Council on Systems Engineering and Object Management Group. It presents a spectrum of activity modeling techniques, ranging from a widely used systems engineering diagram, the EFFBD, to continuous flow modeling. The techniques include control capabilities, continuous system concepts, and others related to functional decomposition and allocation. The article also describes refinements of activity modeling concepts identified during SysML development. © 2006 Wiley Periodicals, Inc. Syst Eng 9:160–186, 2006This article is a US Government work and, as such, is in the public domain in the United States of America. Commercial equipment and materials might be identified to adequately specify certain procedures. In no case does such identification imply recommendation or endorsement by the U.S. National Institute of Standards and Technology, nor does it imply that the materials or equipment identified are necessarily the best available for the purpose.
Airborne Endotoxin and Β-D-Glucan in PM1 in Agricultural and Home Environments

Objectives: Concentrations of microbial cell wall components such as endotoxin and β-D-glucan in airborne submicrometer particle size fraction (PM1, defined as particles with median aerodynamic diameter, da ≤ 1 μm) have not been well characterized. In this study, airborne concentrations of endotoxin and β-D-glucan among different size fractions were quantified in two distinctly different environments: farms and homes. Effect of microbial source (farm type for farms and mold damage for homes) on size-fractionated concentrations was investigated. Methods: Airborne endotoxin and β-D-glucan were collected on 7 farms and 184 suburban homes using NIOSH twostage sampler, a cyclone air sampler that fractionates airborne particles into three size fractions: ≤ 1 μm, 1–1.8 μm and ≥ 1.8 μm. Results: Geometric means (geometric standard deviations) of airborne total endotoxin concentration on farms and in homes were 1.20 × 10 4 (7.57) EU/m 3 and 2.67 (3.82) EU/m 3 , respectively. Similar values of airborne total β-D-glucan concentrations were 1.80 × 10 3 (152.88) ng/m 3 and 1.91 (2.83) ng/m 3 , respectively. Relative proportions of PM1 endotoxin, however, were significantly higher (p < 0.001) in home samples (7.9%) than in farm samples (0.3%). Likewise, the proportion of PM1 β-D-glucan was significantly higher (p < 0.001) in homes (28.2% vs. 2.3%). Farm type significantly influenced concentrations of PM1 β-D-glucan (p < 0.05) and total β-D-glucan (p < 0.001). Conclusions: The results of this study demonstrate higher proportions of PM1 endotoxin and β-D-glucan in homes compared to farms. These data further emphasize the importance of conducting size-selective air sampling for microbial exposure assessment in homes.
Tachistoscopic recognition thresholds following paired-associate learning

In three experiments, PA learning was followed by the measurement of tachistoscopic thresholds for the stimulus and the response words, as well as for control words not used in the learning. In all experiments, response words had significantly lower thresholds than did stimulus words. The variable of word frequency was found in the first experiment to affect control words more than the other words; furthermore, the contrast in thresholds for low and high frequencies was greater for stimulus words than for response words. Amount of S-R similarity was found, in Exp. II, to affect thresholds of stimulus words slightly more than thresholds of response words. In Exp. III, the amount of PA learning (50%, 100% and 150% criterion) exerted little influence on the recognition of the stimulus items; the response items exhibited a lowering of thresholds from the 50% to the 100% groups and a rise in threshold for the 150% criterion group.
Temperature dependent spectral densities and quantum activated rate theory

The variability with temperature of spectral densities and rates calculated with quantum activated rate theory is investigated. Classical spectral densities at two temperatures are computed via molecular dynamics for a model of proton transfer in methyl chloride. In addition, quantum dynamics is computed for spectral densities which artificially boost variability at low frequency. We find significant variation in computed spectral densities at moderate frequency. These variations, however, have little effect on overall computed quantum dynamics. In contradistinction, artificial variation in spectral densities at the lowest frequencies can generate fairly significant effects on quantum dynamics. Detailed flux correlation function calculations are presented which illustrate this phenomenon.
Integrating Advanced Information Systems and Technology in Future Organizations

With major technical change taking place every two years, the control of old scientific management is now seriously challenged. This situation presents either an opportunity or frustration and must be addressed towards making order out of what otherwise would be chaos. It is high time that the matter of integrating advanced information systems (AIS) be seriously addressed. Over the short history of computer‐based information systems, professionals have gone through a series of generations which were initially based on heavy technical developments of hardware, soon followed by software, and later by peopleware. Information systems (IS) soon became a feature of major courses of action in carrying out business functions. A greater demand for applications led to the need for integrated systems where business processes were facilitated and enhanced by information technology (IT). Technology and systems are changing; opportunities for success as well as competitive pressures are cascading on management; and man...
Critical Thinking in the Tower Ivory.

In the midst of Nathaniel Hawthorne’s much celebrated short story, “The Celestial Railroad” (1843), which recreates the journey of John Bunyan’s Pilgrim’s Progress by train, Hawthorne and his fellow passengers ride by the cave where, in Bunyan’s day, lived the cruel giants Pope and Pagan. These two had disappeared, but in their den now dwelt a new menace, “the Giant Transcendentalist,” to whom Hawthorne gave this amusing description:
The Intellectual and Moral Integrity of Bioethics: Response to Commentaries on “A Case Study in Unethical Transgressive Bioethics: 'Letter of Concern from Bioethicists' About the Prenatal Administration of Dexamethasone”

In our target article we showed that the Letter of Concern (LoC) fails to meet accepted standards for presenting empirical data for the purpose of supplementing a normative claim and for argument-b...
An instantaneous optimization based power management strategy to reduce fuel consumption in hydraulic hybrids

An instantaneous optimization based power management strategy for output-coupled power-split based hydraulic hybrids has been described in this work. Design considerations for a hydraulic accumulator based regenerative system for hybrids have been outlined. Optimal operation of the non-hybrid version of the power-split transmission provides useful insight into the system optimization and its result has been utilized later. Instantaneous optimization based control combines the efficient system operation with the braking energy regeneration to achieve fuel savings with the hydraulic hybrids in this work. Fuel mileage for a hybrid passenger car has been simulated for standard drive cycles under the instantaneous optimization based control. An output-coupled power-split transmission prototype built on the Hardware-In-the-Loop (HIL) principle has been described briefly. Proposed instantaneous optimization based control has been implemented on the test-rig. The proposed management strategy is compared through measurements and simulations to validate its effectiveness in improving fuel economy.
Physiological Changes in Caged Layers During a Forced Molt 2. Gross Changes in Organs

Abstract The effects of forced molting on body weight and the absolute and relative weights of the liver, ovary, oviduct, right adrenal, and spleen were studied. White Leghorn hens which were reared and maintained under commercial conditions were force molted by reducing daylength as well as by withdrawing feed and water. This procedure induced a pause in egg production within one week of the initiation of feed removal. Four trials were conducted. In Trial 1 the hens were sampled at weekly intervals for 56 days beginning at the time feed was removed. In Trials 2, 3, and 4 the hens were sampled either daily or on alternate days for up to 22 days beginning at the time of feed removal. The absolute and relative weights of the liver, ovary, and oviduct were decreased significantly. Body weight decreased consistently. No consistent trend over the four trials was found in the absolute or relative weights of the right adrenal or the spleen.
Modelling of charging effects in plasma immersion ion implantation

Abstract The charging effects of plasma immersion ion implantation on several device structures is simulated. The simulations use an analytical model which couples the interaction of the plasma and IC devices during plasma implantation. The plasma model is implemented within the circuit simulator SPICE, which allows the model to uses all of the IC device models existing within SPICE. The model of the Fowler-Nordheim tunneling current through thin gate oxides of MOS devices is demonstrated, and shown how it can be used to quantify the damage induced. Charging damage is shown to be strongly affected by the device structure.
Molecular surface electrostatic potentials in relation to noncovalent interactions in biological systems

Noncovalent interactions are predominantly electrostatic in nature. It follows that an effective tool for their investigation and elucidation is the electrostatic potential on the molecular surface. We have shown that a variety of condensed phase macroscopic properties can be expressed quantitatively in terms of certain site-specific and global statistical quantities that characterize the overall pattern of the surface potential. We are now extending this approach to interactions in biological systems. Several applications will be discussed, including initial qualitative studies of dioxins, a series of anticonvulsants and some tetracyclines, the nucleotide bases, and a recent quantitative treatment of the anti-HIV activities of three groups of reverse transcriptase inhibitors. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Discovering Conformational Sub-States Relevant to Protein Function

Background Internal motions enable proteins to explore a range of conformations, even in the vicinity of native state. The role of conformational fluctuations in the designated function of a protein is widely debated. Emerging evidence suggests that sub-groups within the range of conformations (or sub-states) contain properties that may be functionally relevant. However, low populations in these sub-states and the transient nature of conformational transitions between these sub-states present significant challenges for their identification and characterization. Methods and Findings To overcome these challenges we have developed a new computational technique, quasi-anharmonic analysis (QAA). QAA utilizes higher-order statistics of protein motions to identify sub-states in the conformational landscape. Further, the focus on anharmonicity allows identification of conformational fluctuations that enable transitions between sub-states. QAA applied to equilibrium simulations of human ubiquitin and T4 lysozyme reveals functionally relevant sub-states and protein motions involved in molecular recognition. In combination with a reaction pathway sampling method, QAA characterizes conformational sub-states associated with cis/trans peptidyl-prolyl isomerization catalyzed by the enzyme cyclophilin A. In these three proteins, QAA allows identification of conformational sub-states, with critical structural and dynamical features relevant to protein function. Conclusions Overall, QAA provides a novel framework to intuitively understand the biophysical basis of conformational diversity and its relevance to protein function.
Functions of flow from porous rock blocks

Abstract This paper presents three functions that describe approximately the flow of fluids between matrix-rock blocks and fractures in a fractured reservoir. The different types of flow described are: transient pressure-difference flow, gravitational drainage of oil and water-oil imbibition interchange. The functions were obtained through simplifications of the mathematical formulations of the three types of matrix-fracture flow interchanges. They were validated through comparison with several results of experiments, analytical models and numerical simulations of flow. The simple mathematical models of matrix-fracture flow presented can be easily implemented in numerical simulators of fractured reservoirs with the benefit of including actual petrophysical properties and dimensions of the fractured medium, in contrast with widely used inaccurate formulations involving parameters.
Relationship between resolution enhancement and multiphoton absorption rate in quantum lithography

The proposal of quantum lithography [Boto et al., Phys. Rev. Lett. 85, 2733 (2000)] is studied via a rigorous formalism. It is shown that, contrary to Boto et al.'s heuristic claim, the multiphoton absorption rate of a (|N,0>+|0,N>) quantum state is actually lower than that of a classical state with otherwise identical parameters. The proof-of-concept experiment of quantum lithography [D'Angelo et al., Phys. Rev. Lett. 87, 013602 (2001)] is also analyzed in terms of the proposed formalism, and the experiment is shown to have a reduced multiphoton absorption rate in order to emulate quantum lithography accurately. Finally, quantum lithography by the use of a jointly Gaussian quantum state of light is investigated to illustrate the trade-off between resolution enhancement and multiphoton absorption rate.
Estimation and model selection in constrained deconvolution

We analyze in detail the estimation problem associated with the following problem. Givenn noisy measurements (y i ,i=1, ...,n) of the response of a system to an input (A(t) wheret indicates time), obtain an estimate ofA(t) given a knownK(t) (the unit impulse response function of the system) under the model: $$y_i = \int_0^{t_i } {A(s)K(t_i - s)ds + \varepsilon _i } $$ where e1,...e n are independent identically distributed random variables with mean zero and common finite variance. In the solution to the problem, the unknown function is represented by a spline function, and the problem is recast in terms of (inequality constrained) linear regression. The main issues addressed are: (a) the comparison of different nonparametric regression methods in this context, and (b) how to do model selection, i.e., given a (finite) set of candidate spline functions, select the (possibly unique) best one using some (statistically based) selection criteria. Different spline candidate sets, and different asymptotic and resampling-based statistical selection criteria are compared by means of simulations. Due to the particular nature of the estimation problem, modifications to the criteria are suggested. Applications to simulated and real pharmacokinetics data are reported.
It Is Better to Flush than to Break under Pressure

In this issue Fromy et al. describe alterations in pressure-induced vasodilation in the populations most prone to development of pressure ulcers of the skin. Advancing our understanding regarding the basic pathophysiological mechanisms mediating the development of pressure ulcers will allow for better delineation of populations at risk. This study provides novel insights into this important and poorly understood entity, using tools that are potentially deployable into clinical practice.
Activation of cerebrocortical type II 5'-deiodinase activity in Syrian hamsters kept under short photoperiod and reduced ambient temperature.

Abstract Cerebrocortical type II thyroxine 5′-deiodinase (5′-D II) was studied in the Syrian hamster. Animals maintained in 14 hr light/day and 20°C ambient temperature and then subjected to acute cold exposure (4°C) for 4 hours did not exhibit changes in cortical 5′-D II activity. Prolonged exposure of hamsters to natural autumnal short photoperiods and reduced ambient temperatures for 8 weeks increased cortical 5′-D II activity compared to hamsters maintained inside under controlled long photoperiod (14:10 LD) and temperature (20 ± 2° C ) conditions. Animals given subcutaneous implants of melatonin and exposed to the natural autumnal condition for 8 weeks exhibited a greater increase in the cortical 5′-D II activity than that in hamsters with blank pellets kept under the same conditions of reduced photoperiod and temperature. Type II 5′-deiodinase activity was not affected by treatment with 6-methoxy-2-benzoxazolinone (6-MBOA), a compound with a chemical structure related to melatonin. All animals maintained outdoors in the natural photoperiod and temperature conditions had depressed circulating thyroxine (T 4 ) and elevated triiodothyronine (T 3 ) concentrations; neither implants of melatonin nor 6-MBOA affected these thyroid hormone levels. It is concluded that serum T 4 is depressed and cerebrocortical 5′-D II activity is stimulated despite the elevation of T 3 levels in this autumnal condition. These responses, unlike classic pineal-mediated responses to environmental changes, are not blocked by subcutaneous implants of melatonin. However, chronic administration of melatonin might augment the cortical 5′-D II response to low serum T 4 or some other component of the autumnal condition.
Dopamine reduces odor- and elevated-K(+)-induced calcium responses in mouse olfactory receptor neurons in situ.

Although D2 dopamine receptors have been localized to olfactory receptor neurons (ORNs) and dopamine has been shown to modulate voltage-gated ion channels in ORNs, dopaminergic modulation of either...
Growth response of microorganisms to vitamins at different temperatures.

This study was carried out to see if changes in temperature might influence the quantitative response of microorganisms in the presence of limited amounts of a required vitamin in a synthetic or semisynthetic medium. An instance of this sort was reported by Robbins and Kavanagh1 with Phycomyces blakesleeanus, in which a limited amount of thiamin at lower temperatures supported heavier growth than at higher temperatures. This difference was evidenced by the fact that almost twice as much dry matterwas produced at 10 C as at 25 C in the same medium supplemented with 1.0 m/i mole of thiamin. In the following year, Lilly and Leonian2 presented evidence that an increase in temperature from 25 C to 30 C greatly increased the need of Rhizobium trifolii, strain 205, for seven vitamins. Barnett and Lilly,3 working with Sclerotinia camellia, reported on the interrelated effects of vitamins, temperature, and pH upon the vegetative growth. Much of the previous work appearing in the literature on nutritional studies of microorganisms in relation to temper-
A Monte Carlo simulation of photon propagation in fluorescent poly(ethylene glycol) hydrogel microsensors

Abstract A Monte Carlo simulation of photon propagation through fluorophore-containing poly(ethylene glycol) hydrogel networks is described. Poly(ethylene glycol) (PEG) hydrogel microspheres are being studied for fluorescent biosensing of small molecular weight analytes such as glucose and paraoxon. A computational approach to assess the fluorescent output from these sensors was developed, in particular investigating the impact of sphere characteristics such as size, scattering, and fluorophore concentrations on sensor response. Monte Carlo simulations of both individual spheres and packed sphere beds were developed to model photon propagation through homogeneous, water-swollen PEG hydrogel microspheres with encapsulated fluorescein isothiocyanate (FITC) and tetramethylrhodamine isothiocyanate (TRITC) dyes. Experimental studies using an integrating sphere were conducted to determine the hydrogel optical properties used in the simulation and spectrofluorimetry studies performed to verify assumptions made in the model regarding quantum yield. Changes in fluorescence quantum yield, hydrogel scattering and absorption coefficients ( μ s and μ a ), hydrogel scattering anisotropy ( g ), and depth of the sphere bed were used to predict optimum sphere size, gel chemistry, and collection geometry.
Differential inhibition of myoblast fusion.

Abstract The aggregation and fusion of myoblasts in the presence of either metabolic inhibitors or alterations in the incubation medium or under conditions which result in structural changes in the cells was studied using previously described assays for the intercellular interactions of myoblasts in suspension [Knudsen, K. A., and Horwitz, A. F. (1977). Develop. Biol. 58, 328]. These perturbations inhibit myoblast fusion differently. For example, energy poisons, prior trypsin or glutaraldehyde treatment, and inhibitors of protein or cholesterol synthesis all inhibit the Ca 2+ -mediated myoblast aggregation. In contrast, whereas myoblasts aggregate in the presence of 20 m M Mg 2+ , these aggregates are dispersed, even after 1–2 hr, with EDTA or trypsin. Furthermore, enriching the fatty acyl chains in elaidate or prior incubation of the myoblasts in the presence of cytochalasin B or colchicine results in aggregates which, after 1–2 hr, are dispersed by trypsin but not by EDTA. Aggregates of unaltered, control myoblasts, on the other hand, begin to show resistance to dispersion by trypsin after these times. These observations support the suggestion that multinucleate cell formation results from a sequence of events. The influence of these perturbations on cellular aggregation also provides some initial, tentative insight into the molecular mechanism of myoblast fusion. Recognition (calcium-mediated aggregate formation) appears to be mediated by a protein(s) that is turning over during the period of fusion competence, while membrane union (formation of aggregates resistant to dispersion by trypsin) most likely involves the direct participation of membrane lipid.
A k-anonymous communication protocol for overlay networks

Anonymity is increasingly important for network applications concerning about censorship and privacy. The existing anonymous communication protocols generally stem from mixnet and DC-net. They either cannot provide provable anonymity or suffer from transmission collision. In this paper, we introduce a novel approach which takes advantage of hierarchical ring structure and mix technique. This proposed protocol is collision free and provides provable k-anonymity for both the sender and the recipient, even if a polynomial time adversary can eavesdrop all network traffic and control a fraction of participants. Furthermore, it can hide the sender and the recipient from each other and thus can be used for anonymous file sharing. The analysis shows the proposed protocol is secure against various attacks. Measurements further demonstrate it is practical.
Our bodies, our selves

(1988). Our bodies, our selves. Australasian Journal of Philosophy: Vol. 66, No. 3, pp. 308-319.
The Passage of the Civil Service Reforms Act of 1978, and the Business and the Union: A Non-Zero Sum Game

The paper seeks to use non-zero sum bargaining theory to analyze the Civil Service Reforms Act of 1978. President Carter believed that business practices can be used in federal bureaucracy to improve the efficiency and productivity in the government. The Carter Administration sought very actively the cooperation of the business and the labor union to pass the reforms. Both the labor union and the business groups bargained intensely to preserve and promote their interests in the reforms. Based on archival data from the President Jimmy Carter Library, this paper analyzes the bargaining position of the labor union and the business groups from the non-zero sum game theory to offer a different perspective on the passage of the Civil Service Reforms Act of 1978.
Metabolism of benzo(a)pyrene by isolated perfused testis and testicular homogenate

Abstract In an effort to improve the extrapolation of laboratory data to man and estimate risk of human reproductive toxicity associated with environmental exposure, the pharmacokinetic parameters of the testicular compartment are being studied. Of particular interest is the variety of enzyme systems capable of activating and detoxicating environmental chemicals and drugs. This report compares the metabolism of benzo(a)pyrene by the isolated perfused testis and testicular homogenates in vitro . The cell free in vitro system metabolized benzo(a)pyrene at a much greater rate than the perfused testis and produced a different spectrum of metabolites. Reliable laboratory prediction of biotransformation by the whole organ or intact animal is an essential aspect of reproductive toxicology.
An Approach to the Core Skeleton of Lancifodilactone F

Two cycloaddition reactions were utilized for the construction of the 5,6,7-tricyclic skeleton of lancifodilactone F and buxapentalactone. A [2+2] ketene cycloaddition reaction was first used to set their adjacent all-carbon quaternary centers at the 5,6-ring junction. An arene−olefin meta-photocycloaddition reaction was then used to install the 6- and 7-membered rings concurrently.
Definition and Assessment of Sampling and Analytical Accuracy

Two independent definitions for quantifying measurement accuracy and two limiting schemes for their assessment are examined in this paper. Gauss' mean square error MSE is compared to the symmetric-range accuracy A, describing the range of measurements about a measurand. Both measures of accuracy account for systematic error (bias) and imprecision so as to quantify the closeness of estimates to the actual values being measured. Remarkably, it is found that the accuracy functions are closely equivalent for most method applications. Furthermore, details are presented on how to compute confidence limits on measurement accuracy so as to account for error in method evaluation. The confidence limits are qualitatively different in the case that the method undergoes extensive initial evaluation in comparison to a continual re-evaluation at each method application. To this end the statistical theories of tolerance as well as more familiar types of confidence intervals are applied.
Magnetic properties and their dependence on deposition parameters of Co/Al2O3 multilayers grown by pulsed laser deposition

Abstract Co/Al 2 O 3 multilayered thin films were grown on Si (111) substrates by pulsed laser deposition (PLD) at temperatures from room temperature (RT) to 600 °C. The Co/Al 2 O 3 multilayered thin film grown at RT contains continuous cobalt layers in alumina matrices, with no evidence of island formation. On the other hand, cobalt showed a tendency to form islands in alumina matrices for growth temperatures in the range of 300–600 °C. All the Co/Al 2 O 3 multilayered thin films showed ferromagnetic behavior up to RT. It was observed that variations in the deposition parameters can significantly influence the magnetic properties of Co/Al 2 O 3 multilayers. Depending on the temperature and pulse rate, RT coercivities in the 50–300 Oe range were observed. Films deposited at 600 °C using a laser pulse rate of 10 Hz exhibited a decrease of coercivity with increasing measurement temperature. On the other hand, films deposited at 600 °C using a reduced pulse rate of 2 Hz demonstrated an “anomalous” relationship between low-temperature coercivity and temperature. In these films, coercivity exhibited a weak tendency to increase with temperature. Squareness ( M r / M s ) of the hysteresis loops and its dependence on the temperature was also shown to be strongly affected by the deposition parameters. These observations have been rationalized on the basis of two competing magnetic anisotropies that act along different directions in the material.
Novel swing-assist un-motorized exoskeletons for gait training.

Robotics is emerging as a promising tool for functional training of human movement. Much of the research in this area over the last decade has focused on upper extremity orthotic devices. Some recent commercial designs proposed for the lower extremity are powered and expensive – hence, these could have limited affordability by most clinics. In this paper, we present a novel un-motorized bilateral exoskeleton that can be used to assist in treadmill training of motor-impaired patients, such as with motor-incomplete spinal cord injury. The exoskeleton is designed such that the human leg will have a desirable swing motion, once it is strapped to the exoskeleton. Since this exoskeleton is un-motorized, it can potentially be produced cheaply and could reduce the physical demand on therapists during treadmill training. A swing-assist bilateral exoskeleton was designed and fabricated at the University of Delaware having the following salient features: (i) The design uses torsional springs at the hip and the knee joints to assist the swing motion. The springs get charged by the treadmill during stance phase of the leg and provide propulsion forces to the leg during swing. (ii) The design of the exoskeleton uses simple dynamic models of sagittal plane walking, which are used to optimize the parameters of the springs so that the foot can clear the ground and have a desirable forward motion during walking. The bilateral exoskeleton was tested on a healthy subject during treadmill walking for a range of walking speeds between 1.0 mph and 4.0 mph. Joint encoders and interface force-torque sensors mounted on the exoskeleton were used to evaluate the effectiveness of the exoskeleton in terms of the hip and knee joint torques applied by the human during treadmill walking. We compared two different cases. In case 1, we estimated the torque applied by the human joints when walking with the device using the joint kinematic data and interface force-torque sensors. In case 2, we calculated the required torque to perform a similar gait only using the kinematic data collected from joint motion sensors. On analysis, we found that at 2.0 mph, the device was effective in reducing the maximum hip torque requirement and the knee joint torque during the beginning of the swing. These behaviors were retained as the treadmill speed was changed between 1–4 mph. These results were remarkable considering the simplicity of the dynamic model, model uncertainty, non-ideal spring behavior, and friction in the joints. We believe that the results can be further improved in the future. Nevertheless, this promises to provide a useful and effective methodolgy for design of un-motorized exoskeletons to assist and train swing of motor-impaired patients.
Accommodating Diversity Through Peabody Classwide Peer Tutoring

We encourage our readers to submit ideas, suggestions, or manuscripts for Spotlight. This feature of Intervention focuses on a specific school program, clinic, camp, or individual concerned with special and remedial education. We would be pleased to assist our readers in developing an article for this column.--GW
Detachments of the Retinal Pigment Epithelium at the Posterior Pole

Multiple vitelliform cysts of the retina, a disorder of unknown cause in which there are multiple detachments of the retinal pigment epithelium at the posterior pole, occurred in five patients. In four patients all lesions were located outside the parafoveal area while one patient showed bilateral foveal elevations associated with more eccentric detachments. Several patients showed slow resolution of some of the detachments with mild disturbances of the pigment epithelium.