cssi/SciSciGPT-SciSciNet huggingface dataset:
A mixed quantum-classical molecular dynamics study of the hydroxyl stretch in methanol/carbon tetrachloride mixtures III: nonequilibrium hydrogen-bond dynamics and infrared pump-probe spectra.

We present a mixed quantum-classical molecular dynamics study of the nonequilibrium hydrogen-bond dynamics following vibrational energy relaxation of the hydroxyl stretch in a 10 mol % methanol/carbon tetrachloride mixture and pure methanol. The ground and first-excited energy levels and wave functions are identified with the eigenvalues and eigenfunctions of the hydroxyl’s adiabatic Hamiltonian and as such depend parametrically on the configuration of the remaining, classically treated, degrees of freedom. The dynamics of the classical degrees of freedom are in turn governed by forces obtained by taking the expectation value of the force with respect to the ground or excited vibrational wave functions. Polarizable force fields and nonlinear mapping relations between the hydroxyl transition frequencies and dipole moments and the electric field along the hydroxyl bond are used, which were previously shown to quantitatively reproduce the experimental infrared steady-state absorption spectra and excited stat...
Antigen-independent signalosome of CARMA1, PKCθ, and TNF receptor-associated factor 2 (TRAF2) determines NF-κB signaling in T cells

NF-κB activation is essential for T-cell responses, and costimulatory molecules in the TNF receptor (TNFR) superfamily are viewed as a major source of this signal. Although the TNFR family recruits TNFR-associated factor (TRAF) molecules leading to IKKα/β/γ activation, it is not clear whether simple binding of TRAFs explains why they are such strong activators of NF-κB and so important for T-cell immunity. We now show that one TNFR family member, OX40 (CD134), after ligation by OX40L, assembles a unique complex that not only contains TRAF2, RIP, and IKKα/β/γ but also CARMA1, MALT1, BCL10, and PKCθ, molecules previously shown to regulate NF-κB activation through the T-cell receptor (TCR). The OX40 signalosome is formed in membrane microdomains irrespective of TCR engagement, and strongly promotes NF-κB activation only if CARMA1 and PKCθ are recruited. This NF-κB signal allows effector/memory T cells to survive when antigen is no longer available. Thus, by recruiting TCR-related intracellular molecules into the TRAF2 complex, OX40 provides the T cell with a high level of NF-κB activity needed for longevity.
Effect of x-rays on the developing teeth of rats

Abstract 1. 1. No disturbance was found in any of the structures except the odontoblasts and the dentin. 2. 2. Dosages of the x-ray given in individual dosage comparable to those used in dental radiography, as shown in Table II, did not cause any defects in the dentin of any teeth of the rats. 3. 3. Greater dosages, as shown in Table III, caused a definite disturbance in calcification of the dentin. 4. 4. This effect was only temporary, and it is probable that only the area undergoing development at the time of exposure was affected. 5. 5. The effects shown in using greater dosages seem to compare favorably with those whom by Leist in his investigation.
A molecular perspective on the polymorphism of acetylcholinesterase

Abstract The precise disposition of acetylcholinesterase within junctional areas is critical to the temporal responses associated with synaptic transmission. Extensive polymorphism in acetylcholinesterase structure provides the necessary requirements to achieve the appropriate localization on specialized extracellular membranes. Doctor Taylor, Schumacher, Maulet and Newton review recent studies which suggest that the molecular structure of this enzyme resembles a secreted rather than an integral membrane protein.
A Sample of NASA Langley Unsteady Pressure Experiments for Computational Aerodynamics Code Evaluation

As computational fluid dynamics methods mature, code development is rapidly transitioning from prediction of steady flowfields to unsteady flows. This change in emphasis offers a number of new challenges to the research community, not the least of which is obtaining detailed, accurate unsteady experimental data with which to evaluate new methods. Researchers at NASA Langley Research Center (LaRC) have been actively measuring unsteady pressure distributions for nearly 40 years. Over the last 20 years, these measurements have focused on developing high-quality datasets for use in code evaluation. This paper provides a sample of unsteady pressure measurements obtained by LaRC and available for government, university, and industry researchers to evaluate new and existing unsteady aerodynamic analysis methods. A number of cases are highlighted and discussed with attention focused on the unique character of the individual datasets and their perceived usefulness for code evaluation. Ongoing LaRC research in this area is also presented.
pH shifts and precipitation associated with metal ions in tissue culture.

Abstract Recently there has been interest in tests to assess the physiological response to surgical implant corrosion products. Both cell culturing in metal-bearing solutions and intramuscular injection of such solutions have been carried out. This paper examines the effects of the constraints of multicomponent equilibrium conditions on the characteristics of the solutions used in these biocompatibility tests. It is demonstrated that unbuffered, they will have pH values shifted from neutral and that in the buffered state, these solutions may contain both dissolved metal ions and insoluble hydroxides. The implications of these characteristics for the interpretation of the results of biocompatibility tests are discussed.
Pfaffian solutions to a (3+1)-dimensional generalized B-type Kadomtsev–Petviashvili equation and its modified counterpart

Abstract A class of exact Pfaffian solutions to a (3+1)-dimensional generalized B-type Kadomtsev–Petviashvili equation is obtained. A set of sufficient conditions consisting of systems of linear partial differential equations involving free parameters is generated to guarantee that the Pfaffian solves the equation. A Backlund transformation of the equation is presented. The equation is transformed into a set of bilinear equations, and a few classes of traveling wave solutions, rational solutions and Pfaffian solutions to the extended bilinear equations are furnished. Examples of the Pfaffian solutions are explicitly computed, and a few solutions are plotted.
Comus and the Zodiacus Vitae

L'influence du poeme didactique de Marcellus Palingenius sur les speculations miltoniennes sur les anges
Ice-Bearing Cumulus Cloud Evolution: Numerical Simulation and General Comparison Against Observations.

Abstract A two-dimensional (axisymmetric) numerical cloud model with parameterized microphysics for water drops and ice particles is described. The parameterized liquid-phase processes include condensation, evaporation, autoconversion of small drops to large ones, and collection of small drops by large ones. The solid-phase processes include heterogeneous sorption nucleation, homogeneous contact nucleation, deposition, sublimation, riming and melting. Both liquid and solid particles may precipitate. The model was used to simulate three different conditions of ice generation as a function of temperature: 1) based on classical concepts of the activity of heterogeneous ice-forming nuclei—suggesting continental cumuli; 2) based on field observations of much greater concentrations of ice particles at warmer temperatures than indicated measurements of heterogeneous ice nuclei—suggesting maritime cumuli; and 3) based on nucleus seeding practice when the goal is to stimulate the growth of cumulus clouds. General ...
Institutional patterns of symptomatic medication in hospitalized patients with advanced cancer

Although standards for palliative treatment of cancer patients at end of life are available, their use is perceived to vary among institutions depending on the prevailing philosophy of care. In this retrospective study, we reviewed the treatment of dying cancer patients receiving intravenous morphine transferred from a cancer center to a palliative care hospital. We recorded the dose of morphine and the use of other palliative medications, including adjuvant analgesic drugs. Although morphine doses tended to decrease after the transfer, the use of palliative medications was similar in the two institutions.
ARTHROPLASTY FOR ARTHRITIS AND ROTATOR CUFF DEFICIENCY

Massive and irreparable loss of rotator cuff tendon integrity can be associated with the development of glenohumeral and acromiohumeral arthritis. Loss of glenohumeral instability provided by the rotator cuff may initiate and perpetuate this unique condition of the shoulder. Proximal humeral replacement arthroplasty is the preferred surgical treatment; special techniques of this procedure are presented. Patients are gratified by the durable restoration of comfort and, to a lesser extent, function.
Beyond power: making bioinformatics tools user-centered

User-centered design techniques can broaden the appeal, use, and effectiveness of Web-based bioinformatics tools.
Efficient symbolic analysis of programs

Abstract This paper is concerned with constructing, for each expression in a given program text, a symbolic expression whose value is equal to the value of the text expression for all executions of the program. A cover is a mapping from text expressions to such symbolic expressions. Covers can be used for constant propagation, code motion, and a variety of other program optimizations. Covers can also be used as an aid in symbolic program execution and for finding loop invariants for program verification. We describe a direct (non-iterative) algorithm for computing a cover. The cover computed by our algorithm is characterized as a minimum of a certain fixed point equation, and is in general a better cover than might be computed by iteration methods (which can compute fixed point covers which are not minimal). Our algorithm is efficient and applicable to all flow graphs. A variant of our algorithm is implemented by Kalman and Kortesoja (IEEE Trans. Software Eng. SE-6 (1980), 512–519) in an optimizing compiler.
Brain regional specificity and time-course of changes in the NMDA receptor-ionophore complex during ethanol withdrawal

Previous work, using membrane receptor binding techniques, demonstrated an increase in hippocampal MK-801 binding sites in mice after chronic ethanol ingestion. The current studies, using quantitative autoradiography, demonstrate that chronic ethanol ingestion also produces increases in MK-801 binding in cerebral cortex, striatum and thalamus, as well as in hippocampus. The persistence of changes in MK-801 binding paralleled the time-course for ethanol withdrawal seizure susceptibility. These results support the hypothesis that an increase in the number of NMDA receptor/channel complexes in hippocampus, and possibly other brain regions, plays a role in the generation or expression of ethanol withdrawal seizures.
Contact Fatigue in Silicon Nitride

A study of contact fatigue in silicon nitride is reported. The contacts are made using WC spheres, principally in cyclic but also in static loading, and mainly in air but also in nitrogen and water. Damage patterns are examined in three silicon nitride microstructures: (i) fine (F)-almost exclusively fully-developed cone cracks; (ii) medium (M)-well developed but smaller cone cracks, plus modest subsurface quasi-plastic damage; (iii) coarse (C)-intense quasi-plastic damage, with little or no cone cracking. The study focuses on the influence of these competing damage types on inert strength as a function of number of contacts. In the F and M microstructures strength degradation is attributable primarily to chemically assisted slow growth of cone cracks in the presence of moisture during contact, although the M material shows signs of enhanced failure from quasi-plastic zones at large number of cycles. The C microstructure, although relatively tolerant of single-cycle damage, shows strongly accelerated strength losses from mechanical degradation within the quasi-plastic damage zones in cyclic loading conditions, especially in water. Implications concerning the design of silicon nitride microstructures for long-lifetime applications, specifically in concentrated loading, are considered.
Preparation and characterization of mixed amido-phosphido compounds of molybdenum(IV). A comparison of π-donating ligands in Mo(NMe2)4, Mo(PCy2)4 and [Mo(NMe2)2(PPh2)2] based on X-ray studies

Abstract Two preparative routes to mixed amido-phosphido complexes [M(NMe2)4-x(PR2)x] have been investigated involving the addition of either R2PH or LiPR2 to hydro-carbon solutions of Mo(NMe2)4. The former method has allowed the replacement of two NMe2 ligands and the isolation of the crystalline compound [Mo(NMe2)2(PPh2)2]. The latter synthetic approach has allowed the isolation of [Mo(NMe2)3P(t-Bu)2]. Both compounds are monomeric in solution and in the solid-state [Mo(NMe2)2(PPh2)2] adopts a structure closely related to those seen for Mo(NMe2)4 and Mo(PCy2)4. Specifically, the MoN (1.941(9) and 1.913(9) A) and the MoP distances (2.260(3) and 2.264(3) (A) are (within the criteria of 3σ) identical to those seen in Mo(NMe2)4 and Mo(PCy2)4, respectively. Furthermore, the Mo(NC2)4, MO(PC2)4 and Mo(NC2)2(PC2)2 units are all arranged in a common manner allowing the pnictinide-containing ligands to π-donate to the d2 Mo(4+) centre. In this instance, NMe2− and PPh2− are both acting as 4-electron donors (σ2+π2) and only subtle distinctions based on the angles at nitrogen and phosphorus imply that the relative π-donor ability is Me2N− > Ph2P−. This result is compared to [1,2−M2(PR2)2(NMe2)4] structures where, based on MP and MN distances together with the angles subtend at nitrogen and phosphorus, the order is clearly established, Me2N− > Ph/2P−. Crystal data for [Mo(NMe2)2(PPh2)2] at −156°C: a=11.151(6), b=29.156(2), c=9.682(5) AA, β = 119.99(2)°, Z = 4, dcalc = 1.351 g cm−3 and space group P21/c
Can a computerized tracking system improve faculty compliance with medical student evaluations

Aim: We examined whether using a new personal digital assistant (PDA)-based computerized tracking system (PDAT) improved the rate of faculty evaluation of students compared to using written clinical encounter cards. Also, we examined whether the addition of e-mail reminders to PDAT affected the evaluation rate.Methods: Retrospective review of collected data on evaluation rates before and after implementation of the computerized tracking system, with and without e-mail reminders. Written encounter cards were available during all phases of the study. The study was conducted at Wake Forest University School of Medicine.Results: Evaluation rates between three separate 3-month periods were compared: (1) written cards alone, (2) PDAT alone and (3) PDAT plus e-mail reminders to the faculty (PDAT-e). The odds ratio (OR) for faculty completion of evaluations was 2.97 when electronic and paper submission were available compared to paper-only evaluations (95% CI: 2.10–4.22, p-value <0.0001). With the addition of e-m...
Opioid-associated central sleep apnea: a case series

Subjects on methadone maintenance for drug addiction have been reported to have central sleep apnea (CSA). However, there are few reports of disordered breathing in patients receiving opioids for chronic pain. We report on six patients (ages 41–68, two females, body mass index 27–34, morphine equivalent doses 120–420 mg/day, Epworth Scales 7–21) referred to our sleep center receiving sustained release opioids for more than 6 months with excessive daytime sleepiness. CSA was defined as apnea–hypopnea index (AHI) more than 5 per hour with ≥50% central events. Bilevel (BLV) titration was done to determine settings and all patients were followed for at least 6 months on nocturnal BLV. AHI ranged 28.4–106 per hour. Time less than 90% O2 saturation ranged 1.8 min to 6.4 h. Four of the patients were treated with chronic BLV ventilation with settings ranging 12–16 cm H2O (inspiratory positive airway pressure)/4–8 cm H2O (expiratory positive airway pressure) with backup rate of 12–16. Among the four patients who used BLV treatment for at least 6 months, Epworth scores improved (by 4, 12, 5, and 9, respectively). Treatment of opioid-associated CSA with BLV corrected nocturnal hypoxemia and reduced sleep fragmentation. Randomized controlled trials, with objective measures of daytime function, are recommended in opioid-induced CSA patients.
Cesarean delivery on demand: what will it cost?

Abstract Objective: The purpose of this study was to estimate the cost differences between elective cesarean delivery and the alternative of attempted vaginal delivery and to assess the economic impact of cesarean delivery on demand. Study Design: Cost data were obtained over a 12-month period from a not-for-profit community hospital to calculate a per-patient cost for clinical alternatives. Results: The average cost of an attempted vaginal delivery without oxytocin (Pitocin) or epidural anesthesia was 15.1% lower in nulliparous women and 20% lower in multiparous women than with elective cesarean delivery. However, in nulliparous women, the addition of Pitocin nullified any cost differences; if epidural anesthesia was also used, total costs exceeded the cost of elective cesarean delivery by almost 10%. The cost of a failed attempt at vaginal delivery was much higher than elective cesarean delivery for both groups. The average cost for all women who attempted vaginal delivery was only 0.2% less than the per-patient cost of elective cesarean delivery. Conclusion: The adoption of a policy of cesarean delivery on demand should have little impact on the overall cost of obstetric care. (Am J Obstet Gynecol 2003;188:1418-23.)
The future of distributed computing: renaissance or reformation?

In the near future, nearly all computers, ranging from supercomputers to smoke detectors, will be shared-memory multiprocessors. This change will affect the distributed computing community in two ways. First, as a Renaissance: perhaps for the first time ever, research in concurrent and distributed computing matters to people outside the community. Second, as a Reformation: the experience of confronting real multiprocessors, like early theorists' experience confronting FORTRAN, will force us to address problems obscured by many of today's elegant but naive computational models. This talk explores these possibilities.
The Influence of Large-Scale Topography on Barotropic Vortex Motion

Abstract The motion of a barotropic vortex in the vicinity of a large-scale topographic feature is examined through numerical integration of the shallow-water equations in an equatorial beta-plane channel. The topographic parameters are chosen to represent the Sierra Madre mountains of Mexico. The motion of the vortex is affected through modification of the asymmetric circulation by vortex stretching associated with divergence of the horizontal velocity field as the air flows across the mountain. A vortex that approaches the topography from the east is accelerated and deflected toward the south and a vortex initially west of the mountain recurves and moves toward the cut. This motion is in contrast to the northwestward motion of a vortex over level terrain. The vortex motion is also compared to the direction of the imposed potential vorticity gradient. The topographic effects described in this paper may be important in forecasting hurricane motion in the eastern North Pacific and western Gulf of Mexico.
Evaluation of short-term and long-term complications after emergent internal iliac artery embolization in patients with pelvic trauma.

Purpose To assess the incidence of long- and short-term complications following internal iliac artery (IIA) embolization after blunt pelvic trauma. Materials and Methods One hundred trauma patients with pelvic fractures underwent pelvic angiography from 1994 through 2006. Sixty-seven patients underwent IIA embolization. These patients were retrospectively identified for medical record review. Short- and long-term complications were defined as those occurring at less than or greater than 30 days, respectively. Complications and outcomes were assessed through chart review and, when possible, a standardized questionnaire. Patients who underwent IIA embolization were compared with matched control patients with blunt pelvic trauma who did not undergo pelvic arteriography. Individuals were matched by age, sex, year of admission, and injury scores. Results There were no significant differences in skin necrosis, sloughing, pelvic perineal infection, or nerve injury between embolized and nonembolized patients within 30 days. There was no significant difference in claudication, skin ulceration, or regional pain at a mean of 18.4 months follow-up. In the long term, buttock, thigh, and perineal paresthesia occur at a significantly higher rate in embolized patients. Skin sloughing in the embolized patient group is an important but rare complication. Conclusions IIA embolization is an important means of controlling pelvic arterial hemorrhage. There is no significant increase in the risk of most evaluated long- and short-term complications in trauma patients who underwent IIA embolization versus those who did not. However, IIA embolization is associated with a marginally significantly increased rate of buttock, thigh, or perineal paresthesia.
Do high property taxes influence family forest land Tenure decisions

Studies have repeatedly documented high property taxes as being a major determinant of a landowner's decision to divest of its forest land. To empirically investigate the relationship between property tax burden and forest land sale activity, property tax data and over 5300 Minnesota forest land sale records from 2000 to 2008 were assembled. Analyses were carried out to identify statistically significant relationships between several measures of private forest land sale activity and forest land property tax burden. The analyses failed to find a statistically positive relationship between the two. Statistically significant negative associations were found between some measures of forest property tax burden and forest land sale frequency, indicating forest land sales activity actually decreased with increasing property tax burden. While high property taxes, no doubt, influence forest land sale decisions, the findings from this study suggest its influence may not be as pervasive as once thought.
Studies on methyl parathion resistance in Heliothis virescens

Abstract Comprehensive studies were conducted to elucidate the resistance mechanisms of a field strain (R) of Heliothis virescens larvae resistant to methyl parathion, when compared with a susceptible laboratory strain (S). In vitro, monooxygenase activity responsible for desulfurating methyl parathion to methyl paraoxon was lower in the R strain while phosphorotriester hydrolase activity, responsible only for methyl paraoxon hydrolysis, was higher in the R strain than the S strain. There was no difference in the total amount of P450, this suggests that the R strain has different isozymes of P450 from those present in the S strain. No differences in glutathione S-transferase activity or in the inhibition of acetylcholinesterase was observed. In vivo, the amount of methyl paraoxon formed increased with time in S, whereas it stayed at a much lower level in R. Following injection, the amount of methyl paraoxon decreased faster in R than in S. The penetration rate of methyl parathion was significantly slower in R than in S for 12 hr after topical application, but was similar after 24 hr. These results indicate that lower monooxygenase activity as well as higher phosphorotriester hydrolase activity are mainly responsible for resistance to methyl parathion in H. virescens. The importance of this combination is discussed in relation to the role each plays in resistance.
Superconductivity in the polymeric phase of Na2CsC60

Abstract We have studied the reversible pressure induced structural transition (primitive cubic to polymeric monoclinic) of Na 2 CsC 60 and the superconductivity in both phases. We have established that the single carbon–carbon bonded polymeric phase of Na 2 CsC 60 is superconducting with an ambient pressure transition temperature about 3 K lower than that for the primitive cubic phase. We believe that an analogous lowering of the transition temperature in the corresponding phase of Na 2 RbC 60 either leads to a very low transition temperature or to a total absence of superconductivity.
Influence of sea spray and rainfall on the surface wind profile during conditions of strong winds

Janin and Cermak (1988) have: determined that airborne sediment in a wind tunnel substantially alters the low-level wind profile. This material apparently causes a reduction in wind speed since the pressure gradient force must accelerate both the air and the sediment, against the force of surface shearing stress. In this brief paper, we explore whether atmospheric wind profiles would be expected to be modified during periods of high winds as a result of heavy rainfall or sea spray. Although there has been controversy regarding the effect of sediment load on pressure drop (e.g., Rangaraju, 1988), our assumption that the wind profile rem~ins logarithmic is based on the physical modeling of Janin and Cermak (1988) in which even with sand loading in the atmosphere, the square root of the total kinetic energy profile remains logarithmic. This means that a given pressure ~adient force can accelerate either air, or a combination of air and a suspended material but when suspended material is present, the actual air velocity will be less. This Note represents an extension of Janin's study of sediment to the suspension of water in the atmosphere. If the effect of the suspended water mass were significant, there could be substantial effects on the aerodynamic response of buildings and other structures in high winds.
Gain saturation effects in supermodes of phase-locked semiconductor laser arrays

A basic modal analysis that includes gain saturation effects in phase-locked semiconductor laser arrays is presented. For a particular supermode operation, different lasers in the array emit different amounts of light, and hence their (waveguide) propagation constants are modified differently. Solving the lasers' rate equations self-consistently with the coupled-mode wave equations seems to provide an answer that is in much better agreement with experimental results than the result using only the coupled-mode analysis.
What Math is the Right Math for Computing? (Abstract Only)

"... we note that undergraduate CS students need enough mathematical maturity to have the basis on which to then build CS-specific mathematics (for example, as specified in the Discrete Structures Knowledge Area), which, importantly, does not explicitly require any significant college-level coursework in calculus, differential equations, or linear algebra." [Computer Science Curricula 2013].Is this true? Perhaps we are finally acknowledging what critics have claimed for many years; namely, that the math traditionally studied by other engineers is the wrong math for computer science. But perhaps the even longer history of organizing college-level math curricula around continuous mathematics recognizes some important source of "mathematical maturity." This session will debate Curricula 2013's claim in order to explore what topics in mathematics, and perhaps logic, statistics, and other related disciplines, a computer science program should include in order to develop appropriate "mathematical maturity" in its students.
Fermion Mass Spectrum in a Generalized Instanton Background

Abstract The spectrum of the squared Dirac operator is studied in the background of symmetric instanton-like configurations on symmetric spaces G/H. The eigenvalues are expressed in terms of Casimir invariants of G and H. These eigenvalues determine the masses of fermions in Kaluza-Klein theories with compactification induced by the generalized instantons. The G-representations of the zero modes are determined for fermions in arbitrary representations of H on S n and CP n . For spheres in even dimensions a comparison with the index theorem reveals a remarkable relation between the N th index (or anomaly) of SO(2 N ) and dimensions of SO(2 N + 1) representations. Using the fundamental indices, we find the topologically stable symmetric solutions on S 2 n for any gauge group, and compare with recent results on local stability.
Expression of neuronal antigens by astrocytes derived from EGF-generated neuroprogenitor cells

Previous studies have demonstrated that astrocytes reacting to CNS injury can express antigens normally associated with neurons. The origin of the reactive astrocytes, i.e., whether they are newly differentiated glial cells or preexisting astrocytes somehow triggered to express neuronal markers, remains difficult to determine using an in vivo model system. An in vitro model may prove more manageable. In the present study, primary brain cultures and EGF-generated neuroprogenitor cells were used to study the expression of neuronal antigens by established (primary) and nascent astrocytes, respectively. Astrocytes derived directly from dissociated mouse brains exhibited a flat morphology typical of type 1 astrocytes. These cells were nestin and GFAP positive and, in most cases, the antigens were colocalized. Primary astrocytes did not appear to express the putative neuronal markers GABA, Tau, or MAP2. Nascent astrocytes derived from EGF-generated progenitor cells showed a similar pattern of GFAP and nestin immunoreactivity. Contrary to primary astrocytes, many GFAP-intensive, stellate astrocytes exhibited Tau and MAP2. These cells also exhibited an intense nestin immunoreactivity. These data suggest that the reactive astrocytes expressing neuronal antigens in response to CNS trauma may be derived from neural progenitor cells rather than from previously differentiated astrocytes.
Lecithinase activity of chloroplasts.

THE low nitrogen/phosphorus ratio of phospholipids isolated from fresh carrot root or cabbage leaves has been shown to result from the loss of nitrogenous bases by enzymatic action during their isolation1,2. A preliminary attempt to extract phospholipids from spinach chloroplasts gave a product with a low nitrogen/phosphorus ratio, suggestive of similar enzymatic degradation. Although lecithinase activity has been investigated in a variety of plants1–6, the occurrence of lecithinases in chloroplasts has not been reported before.
The Effects of Asthma Experience and Social Demographic Characteristics on Responses to the Chicago Community Asthma Survey-32

Introduction The Chicago Community Asthma Survey (CCAS-32) is an instrument forcharacterizing the general public's knowledge, attitudes, and beliefsrelated to asthma. The purpose of this study was to examine the effectsof asthma experience and social demographic characteristics on asthmaawareness among the general public. Methods TheCCAS-32 consists of 21 dichotomous items, designed primarily to testasthma knowledge, and 11 Likert-scale items, focusing on asthmaattitudes and beliefs. From December 1997 through February 1998, arandom-digit dialing method was used to administer the CCAS-32 via atelephone survey of Chicago-area (seven-county) residents ≥ 18 years. Each respondent's asthma experience was classified as “person withasthma,” “family/household experience,” or “no/low asthmaexperience.” Demographic variables included sex, age, education, race/ethnicity, urban vs suburban residence, and income. Results Five hundred sixty-eight Chicago-area residentscompleted the survey (response rate of 40.6%). Of these, 43.3% wereaged 35 to 64 years, 71.3% were women, 66.7% were white, and 71.3%had completed at least some college. Sixty-two percent had no or lowasthma experience, 28.5% had family or household experience, and 9.5%were persons with asthma. The mean percentage (± SE) of correct, ordesirable, responses to asthma knowledge questions was 71.9 ± 0.5%,with a range from 31.9 to 95.1%. The mean percentage of desirableresponses differed significantly between persons with no or low asthmaexperience, family or household asthma experience, and persons withasthma (70.0 ± 0.6%, 74.0 ± 0.9%, and 77.7 ± 1.2%,respectively, p Conclusions The results of this study suggestthat the CCAS-32 can detect meaningful differences between groups withdifferent degrees of asthma experience ( ie ,discriminative validity). Using the CCAS-32, it may be possible toidentify subpopulations with differences in asthma awareness, thusproviding guidance for the design of messages to target community andpublic awareness of asthma.
Path analysis of a theoretical model of persistence in higher education among low-income black youth

Path analysis is used to examine the process of persistence in higher education among a sample of 403 low-income black youth attending a variety of institutions throughout the United States. The model explores the role of college experiences — academic and social integration and academic achievement. Although social integration was misspecified, the model expiains 32% of persistence variance when academic integration is specified prior to academic achievement. The direct effect of college grades is strongest, accounting for half of the explained variance. Academic integration is actually more important than previously believed, exerting an indirect influence through grades. Since college experiences are more important than background characteristics, persistence among low-income minority youth could be improved by program interventions.
The formalities of informal improvement: technical and scholarly knowledge at work in do-it-yourself urban design

Unauthorized yet functional and civic-minded “do-it-yourself urban design” contributions have seen growing interest in recent years. Authorities and community members alike rightfully wonder about the meanings of these actions and the questions they raise about rights, responsibilities, contexts, and consequences. Building from a multi-year study of DIY urban design across 17 cities, this paper focuses on the backgrounds and methods of these would-be local improvers. In particular, it demonstrates that many are informed by sophisticated knowledge of scholarly urban theory and official planning and design standards. Referencing debates on informality and formality in urbanism, I show that highly technical, academic, and formalized elements pervade these informal efforts, suggesting a gray area in our normative assumptions about official versus unauthorized placemaking. I argue that this knowledge enables and inspires many do-it-yourselfers’ actions and produces a complex and potentially problematic reflexi...
Self‐identity, ethnic affinity and national consciousness: An example from rural Hausaland*

(1986). Self‐identity, ethnic affinity and national consciousness: An example from rural Hausaland. Ethnic and Racial Studies: Vol. 9, No. 4, pp. 427-444.
Quenched hadronic screening lengths at high temperature

Abstract We measure the spatial screening lengths of local meson and baryon operators in the deconfined phase of pure SU(3) gauge theory. We work on a lattice of size 8 2 ×24×4 at a temperature T =1.5 T c , with T c the deconfinement temperature. The scre ening lengths are found in parity doublets and the chiral projections for the meson and baryon correlation functions are consistent with unbroken chiral symmetry. Our results are in good quantitative agreement with the full QCD results of Gottlieb et al. at the same temperature.
Sensitivity and specificity: imperfect predictors of guideline utility in radiology

Objective: Many ‘‘guideline-development studies’’ have presented the sensitivity (SN) and specificity (SP) of a new decision tool to describe the potential improvements in utilisation of imaging techniques as a result of adopting the new guideline. However, SN and SP are measures designed to assess how well a new guideline compares with a gold standard. These measuresdo not evaluate how many patients with a positivetest actually have the disease; nor do they evaluate how many patients with a negative test do not have the disease. To evaluate these characteristics of a decision tool, other measures, namely the positive predictive value (PPV) and negative predictive value (NPV), should be calculated. This report highlights some of the main methodological challenges in interpretation of the studies that attempt to evaluate the development of an imaging guideline and the effectiveness of an imaging guideline in real world practice. Methods: We define four key measures of a decision tool: SN, SP, PPV and NPV. Using data from two hypothetical populations, we explain how these measures can be calculated and interpreted. We place special emphasis on the purpose of and differences between the SN–SP and PPV–NPV. Results: Borrowing information from two studies, we demonstrate how these measures should be used in the radiology healthcare services research to evaluate decision guidelines. Conclusion: The use of appropriate measures for the specific question at hand will ensure the guidelines are useful, safe, cost reducing and effective clinical tools.
Descendants of Primitive Substitutions

Let s = (A, τ) be a primitive substitution. To each decomposition of the form τ (h) = uhv we associate a primitive substitution D[(h,u)](s) defined on the set of return words to h . The substitution D[(h,u)](s) is called a descendant of s and its associated dynamical system is the induced system (Xh, Th) on the cylinder determined by h . We show that \( {\cal D}(s) \) , the set of all descendants of s , is finite for each primitive substitution s . We consider this to be a symbolic counterpart to a theorem of Boshernitzan and Carroll which states that an interval exchange transformation defined over a quadratic field has only finitely many descendants. If s fixes a nonperiodic sequence, then \( {\cal D}(s) \) contains a recognizable substitution. Under certain conditions the set \( \Omega (s) = \bigcap_{s^\prime \in {\cal D}(s)}{\cal D}(s^\prime ) \) is nonempty.
Relative configuration of thioridazine enantiomers

The relative configuration of the enantiomers of thioridazine was defined to explore the stereochemistry associated with the selective binding of (−)-thioridazine to dopamine D-1 receptors and (+)-thioridazine to D-2 receptors. Using a seven-step stereoconservative synthesis, (−)-(S)-2-piperidinecarboxylic acid was converted to (−)-(S*)-2-(2-chloroethyl)-1-methylpiperidine, a literature (−)-thioridazine synthetic precursor. Accordingly, (−)- and (+)-thioridazine are the (S)- and (R)-enantiomers, respectively.
Childhood pemphigus foliaceus. Report of a case.

• A case is reported of a 4-year-old black boy with pemphigus foliaceus. The patient is unusual because of age, sex, race, and distribution of lesions. Confirmation of diagnosis was made by both routine histopathology and direct immunofluorescence microscopy. The patient responded rapidly to prednisone therapy. (Arch Dermatol116:679-680, 1980)
Observations on the absorption spectra of fluorescein, fluorescein derivatives and conjugates.

Abstract 1. 1. Rapid loss in the characteristic maximum at 490 mμ occurs in solutions of fluorescein (uranin) below pH 7.0 with elimination of fluorescence at pH 2.0. A new absorption band appears in these solutions below pH 5.0 with a maximum at 430 mμ at pH 2.0. 2. 2. On the basis of samples of fluorescein amine II prepared in different laboratories, but having a melting point of 313 °, infrared absorption spectra have been obtained which serve as a standard for the preparation of this amine. 3. 3. The ultraviolet absorption spectrum has been shown of fluorescein amine isomer II in dioxane-acetone solution and of the change in spectrum which occurs after conversion by phosgene to fluorescein isocyanate. 4. 4. The ultraviolet absorption spectrum of the fluorescein nucleus in aqueous buffered solution, pH 7.6, showing a maximal band at 490 mμ and two minor bands at 280 and 325 mμ, has been obtained. The changes which occur in the intensity of these bands after conjugation to rabbit globulin have been shown. 5. 5. The emission spectra solutions of fluorescein and fluorescein-globulin conjugates have a longer wavelength than their absorption spectra with an optimum emission band at 550 mμ.
Revival of saprotrophic and mycorrhizal basidiomycete cultures after 20 years in cold storage in sterile water.

Vegetatively colonized agar cores of 69 basidiomycete fungus isolates (48 species in 30 genera and 17 families) were stored at 5 °C in tubes of sterile distilled water without manipulation for 20 years. These were represented by 34 isolates of saprotrophic fungi (29 species in 19 genera) and 35 isolates of mycorrhizal fungi (19 species in 11 genera). Viability was evaluated based on revived growth on agar media at room temperature. Fifty-seven of the 69 isolates (82.6%) grew vigorously when revived after storage for 20 years; of the 34 saprotrophic fungus isolates, 30 revived (88.2%); of the 35 mycorrhizal fungus isolates, 27 revived (77.1%). Thirteen isolates of Laccaria were all viable after 20 years, indicating cold storage in sterile water to be a good method for maintaining this important genus of mycorrhizal fungi. In general, however, mycorrhizal fungus species demonstrated lower viability than saprotrophic fungi.
Three-Dimensional Embedded Subband Coding with Optimized Truncation (3-D ESCOT)

Abstract This paper presents an efficient video coding algorithm: Three-dimensional embedded subband coding with optimized truncation (3-D ESCOT), in which coefficients in different subbands are independently coded using fractional bit-plane coding and candidate truncation points are formed at the end of each fractional bit-plane. A rate-distortion optimized truncation scheme is used to multiplex all subband bitstreams together into a layered one. A novel motion threading technique is proposed to form threads along the motion trajectories in a scene. For efficient coding of motion threads, memory-constrained temporal wavelet transforms are applied along entire motion threads. Block-based motion threading is implemented in conjunction with 3-D ESCOT in a real video coder. Extension of 3-D ESCOT to object-based coding is also addressed. Experiments demonstrate that 3-D ESCOT outperforms MPEG-4 for most test sequences at the same bit rate.
Jumping on the NII bandwagon

Many requests for proposals have been issued since the last issue of this column appeared six months ago. We first briefly touch upon some recent developments along the policy/legislation front concerning NSF, ARPA, and HPCC. We then recap the recent requests for proposals from ARPA, NSF, Air Force, NASA, and Army.
In situ colloid mobilization in Hanford sediments under unsaturated transient flow conditions: effect of irrigation pattern.

Colloid transport may facilitate off-site transport of radioactive wastes at the Hanford site, Washington State. In this study, column experiments were conducted to examine the effect of irrigation schedule on releases of in situ colloids from two Hanford sediments during saturated and unsaturated transientflow and its dependence on solution ionic strength, irrigation rate, and sediment texture. Results show that transient flow mobilized more colloids than steady-state flow. The number of short-term hydrological pulses was more important than total irrigation volume for increasing the amount of mobilized colloids. This effect increased with decreasing ionic strength. At an irrigation rate equal to 5% of the saturated hydraulic conductivity, a transient multipulse flow in 100 mM NaN0 3 was equivalent to a 50-fold reduction of ionic strength (from 100 mM to 2 mM) with a single-pulse flow in terms of their positive effects on colloid mobilization. Irrigation rate was more important for the initial release of colloids. In addition to water velocity, mechanical straining of colloids was partly responsible for the smaller colloid mobilization in the fine than in the coarse sands, although the fine sand contained much larger concentrations of colloids than the coarse sand.
Optical hybrid processing utilizing photonic crystals incorporating biological materials

Tunable photonic crystal (PC) waveguides have been designed using plane-wave expansion calculations for application to photonic integrated circuits. Wavelength selective propagation has been observed in silicon-on-insulator (SOI) PC waveguides fabricated by electron-beam lithography and inductively coupled plasma etching. Incorporation of DNA into an SOI PC lattice has been demonstrated, and novel tunable PC devices using biophotonic materials have been considered.
Repurposing Diabetes Drugs for Brain Insulin Resistance in Alzheimer Disease

A growing body of clinical and epidemiological research suggests that two of the most common diseases of aging, type 2 diabetes (T2DM) and Alzheimer disease (AD), are linked. The nature of the association is not known, but this observation has led to the notion that drugs developed for the treatment of T2DM may be beneficial in modifying the pathophysiology of AD and maintaining cognitive function. Recent advances in the understanding of the biology of T2DM have resulted in a growing number of therapies that are approved or in clinical development for this disease. This review summarizes the evidence that T2DM and AD are linked, with a focus on the cellular and molecular mechanisms in common, and then assesses the various clinical-stage diabetes drugs for their potential activity in AD. At a time when existing therapies for AD offer only limited symptomatic benefit for some patients, additional clinical trials of diabetes drugs are needed to at least advance the care of T2DM patients at risk for or with comorbid AD and also to determine their value for AD in general.
Solving DDEs in MATLAB

We have written a program, dde23, to solve delay differential equations (DDEs) with constant delays in MATLAB. In this paper we discuss some of its features, including discontinuity tracking, iteration for short delays, and event location. We also develop some theoretical results that underlie the solver, including convergence, error estimation, and the effects of short delays on stability. Some examples illustrate the use of dde23 and show it to be a capable DDE solver that is exceptionally easy to use.  2001 IMACS. Published by Elsevier Science B.V. All rights reserved.
Synthesis and characterization of poly(4‐vinylpyridine) substituted with a novel betaine salt derived from 4,5‐dicyanoimidazole

A novel betaine internal salt (3) has been synthesized by the reaction of pyridine with 1-methyl-2-bromo-4,5-dicyanoimidazole (1). The reaction of pyridine with 1 serves as a model for the reaction of poly(4-vinylpyridine) with 1. The reaction of poly(4-vinylpyridine) with 1 gives betaine salt substituted polymers which were characterized by IR, NMR, UV-visible spectroscopy, and viscometry. The substituted polymers were compared to the model compound (3) and to unsubstituted poly(4-vinylpyridine) in order to determine polymer structure and the degree of substitution. One of the substituted polymers shows polyelectrolyte behavior. Thermal characterization of the substituted polymers shows two exothermic transitions at 260 and 340°C attributed to chemical reactions of the pendant groups.