cssi/SciSciGPT-SciSciNet huggingface dataset:
In vivo bioluminescent imaging reveals temporal and spatial dynamics of giardiasis

Giardia lamblia is a protistan parasite causing acute and chronic diarrheal disease in over one billion people worldwide, primarily in areas lacking adequate water treatment. Animal hosts ingest Giardia cysts that excyst in the gut to become motile trophozoites. Trophozoites colonize the small intestine, later differentiating into infectious cysts that are excreted and can contaminate water sources. Due to the limited accessibility of the gastrointestinal tract, our understanding of in vivo temporal and spatial dynamics of giardiasis is largely inferred from parasite physiology in laboratory culture. While in vitro models of giardiasis are informative, they may not adequately mirror in vivo parasite physiology in the host. To evaluate in vivo giardiasis directly, we developed bioluminescent imaging (BLI) methods to quantify temporal and spatial dynamics of giardiasis in mice using parasites expressing constitutive or encystation-specific luciferase bioreporters. Consistent with prior work, BLI confirms that metabolically active parasites primarily colonize the proximal small intestine. Contrasting with previous studies, we find that encystation is initiated and peaks early during infection and is localized to foci of high parasite density in the small intestine. Both BLI and immunostaining of encystation-specific vesicles (ESVs) corroborate that encystation is initiated in the proximal rather than the distal small intestine. This non-invasive method of imaging giardiasis provides an unprecedented and precise quantification of in vivo temporal and spatial patterns of infection, and an improved animal model for evaluation of anti-giardial drugs.
Resurgent analysis of SU(2) Chern-Simons partition function on Brieskorn spheres Σ(2, 3, 6n + 5)

$$ \hat{Z} $$ -invariants, which can reconstruct the analytic continuation of the SU(2) Chern-Simons partition functions via Borel resummation, were discovered by GPV and have been conjectured to be a new homological invariant of 3-manifolds which can shed light onto the superconformal and topologically twisted index of 3d $$ \mathcal{N} $$ = 2 theories proposed by GPPV. In particular, the resurgent analysis of $$ \hat{Z} $$ has been fruitful in discovering analytic properties of the WRT invariants. The resurgent analysis of these $$ \hat{Z} $$ -invariants has been performed for the cases of Σ(2, 3, 5), Σ(2, 3, 7) by GMP, Σ(2, 5, 7) by Chun, and, more recently, some additional Seifert manifolds by Chung and Kucharski, independently. In this paper, we extend and generalize the resurgent analysis of $$ \hat{Z} $$ on a family of Brieskorn homology spheres Σ(2, 3, 6n + 5) where n ∈ ℤ+ and 6n + 5 is a prime. By deriving $$ \hat{Z} $$ for Σ(2, 3, 6n + 5) according to GPPV and Hikami, we provide a formula where one can quickly compute the non-perturbative contributions to the full analytic continuation of SU(2) Chern-Simons partition function.
Pharmacologic Similarities and Differences Among Hallucinogens

Hallucinogens constitute a unique class of substances that cause changes in the user's thoughts, perceptions, and mood through various mechanisms of action. Although the serotonergic hallucinogens such as lysergic acid diethylamide, psilocybin, and N,N-dimethyltryptamine have been termed the classical hallucinogens, many hallucinogens elicit their actions through other mechanisms such as N-methyl-D-aspartate receptor antagonism, opioid receptor agonism, or inhibition of the reuptake of monoamines including serotonin, norepinephrine, and dopamine. The aim of this article is to compare the pharmacologic similarities and differences among substances within the hallucinogen class and their impact on physical and psychiatric effects. Potential toxicities, including life-threatening and long-term effects, will be reviewed.
Creating Informal Learning Environments on the World Wide Web

Publisher Summary This chapter describes principles and strategies that support the creation of informal learning environments on the Web. As a medium, the Web is not well suited to lengthy presentations of text, although book-length manuscripts can easily be made into Web pages. It is an ephemeral medium that encourages brief interactive encounters. The Web favors graphics over text, browsing over contemplation, and economy over depth. The dilemma for educators is how to build on the strengths of the Web without being shallow. The solution is quality over quantity. Links to other Web sites, annotated bibliographies, suggestions for further inquiry, and even links to more elaborate experiences within the same Web site are proven devices for piquing visitor interest and encouraging further exploration. The Web holds great promise as a learning technology, in large measure, because of its potential for making abstract notions tangible. Informal learning environments are places where visitors can explore, interact, play, and learn from experience.
Ceteris Paribus, there is No problem of provisos

Much of the literature on ceteris paribus laws is based on a misguided egalitarianism about the sciences. For example, it is commonly held that the special sciences are riddled with ceteris paribus laws; from this many commentators conclude that if the special sciences are not to be accorded a second class status, it must be ceteris paribus all the way down to fundamental physics. We argue that the (purported) laws of fundamental physics are not hedged by ceteris paribus clauses and provisos. Furthermore, we show that not only is there no persuasive analysis of the truth conditions for ceteris paribus laws, there is not even an acceptable account of how they are to be saved from triviality or how they are to be melded with standard scientific methodology. Our way out of this unsatisfactory situation to reject the widespread notion that the achievements and the scientific status of the special sciences must be understood in terms of ceteris paribus laws.
Reconceptualizing Vagueness: Legal Rules and Social Orders

"'[I]ndefiniteness' is not a quantitative concept."' The void for vagueness doctrine is traditionally understood as concerned with the capacity of legal rules to control conduct. The doctrine underwrites the clarity of the law's distinction between acceptable and forbidden behavior, so as both to guide the actions of citizens and to restrict the discretion of government officials. In the words of a recent Supreme Court decision, the doctrine, "[a]s generally stated,... requires that a penal statute define the criminal offense with sufficient definiteness that ordinary people can understand what conduct is prohibited and in a manner that does not encourage arbitrary and discriminatory enforcement."2 The traditional account of void for vagueness doctrine thus focuses on the nature of legal rules. It invites us to perceive the question of vagueness as a continuous variable, as "a matter of degree,"3 so that one can speak of a rule as having more or less "definiteness" and therefore as exercising more or less control over government caprice and citizen conduct. For this reason an unconstitutionally vague statute can be rewritten so as to be clearer or more precise. Hence vagueness analysis is said to "address itself to the form of regulation, without reference to the ultimate amenability to regulation of its subject."4 I do not mean to deny that this traditional image of vagueness doctrine is often valid and appropriate. But I wish in this Essay to call attention to a significant class of cases in which this image is inaccurate and misleading. In these cases courts do not use vagueness doctrine to focus on the isolated properties of legal rules, but rather to analyze the relationship between legal rules and forms of social order. My hypothesis is that different kinds of legal rules presuppose and instantiate different forms of social order, and that vagueness doctrine is frequently employed to distinguish among the
Stress Analysis and Fracture in Nanolaminate Composites

A stress analysis is performed on a nanolaminate subjected to bending. A composite mechanics computer code that is based on constituent properties and nanoelement formulation is used to evaluate the nanolaminate stresses. The results indicate that the computer code is sufficient for the analysis. The results also show that when a stress concentration is present, the nanolaminate stresses exceed their corresponding matrix-dominated strengths and the nanofiber fracture strength.
Performance of a High-Resolution Mesoscale Tropical Prediction Model

Publisher Summary This chapter examines the performance of a high-resolution mesoscale tropical prediction model. There are basically two types of mesoscale models, including quasistatic models and nonhydrostatic mesoscale models. The quasistatic models make use of horizontal resolutions of the order of 50 km or larger and can resolve mesoscale phenomena whose scale is of the order of a few hundred kilometers. The nonhydrostatic mesoscale models use a horizontal resolution of less than 5 km. The physical parametrizations of the model are largely based on the developments from global spectral model. These include shallow and deep moist convection, detailed calculation of radiative processes including cloud feedback processes, and a variable solar zenith angle. The surface fluxes are based on similarity theory and are coupled to the computation of surface hydrology and surface energy balance and they distinguish between the stable and unstable surface layers. The dynamical aspects of the regional model are also elaborated.
Upside-down Venture Capitalists and the Transition Toward Pyramidal Firms: Inevitable Progression, or Failed Experiment?

The early-stage venture capital (VC) industry has long been dominated by small firms comprising senior venture capitalists and few junior staff. However, during the late 1990s, a group of firms changed their internal structures, adopting pyramidal structures and redesigning internal processes to leverage the efforts of junior staff. In doing so, they followed first-movers in other professional services industries that transitioned to pyramidal models in the 20th century. Has the recent industry downturn terminated the transition, or simply delayed it? This chapter analyzes the events that led the VC firms to transition, the barriers to doing so, and related issues affecting the industry's future.
Internal Hydrostatic Pressure of the Fundulus Egg I. The Activated Egg

By means of a mercury manometer connected to a micropipette, the internal hydrostatic pressure of the unfertilized Fundulus egg was measured. Upon activation of the egg by micropuncture when the platelets in the cortex of the egg proper disappeared, there was a progressively increasing internal pressure which finally stabilized at 150 mm. Hg. The pressure was accompanied by the formation of a perivitelline space which contained a clear, colloidal material. The measured internal hydrostatic pressure of the egg was diminished by any means which decreased the perivitelline space. It was concluded that the perivitelline substance is the chief factor contributing to the pressure. The changes in volume of the egg proper are inversely proportional to the size of the perivitelline space, indicating that the surface of the egg proper is permeable to water.
Age dependence of mineral dissolution and precipitation rates

[1] Understanding the rates of weathering, and more generally dissolution and precipitation in porous materials, is important for many applications including modeling the global carbon cycle and predicting short-term and long-term behavior in subsurface carbon sequestration sites. However, interpretation of the rates remains elusive as they have been observed to vary with location, measurement procedure, and time. We argue that the mechanisms responsible for the apparent aging in the rates, or gradual decrease over time, can be partially determined by noting which measure of time best characterizes the dependence. If the rate is best described as a function of residence time, then hydraulic and transport limitations are responsible for the variations. If reaction age is a better independent variable, then limitations in the chemical reaction at the fluid-mineral interface are responsible. We discuss several mechanisms in each category and construct mathematical models that demonstrate quantitatively how they affect time variation in reaction rates. These include nonlinear kinetics, disordered kinetics, and a reprecipitation model that accounts for the limited access to the bulk of a dissolving solid. We apply the reprecipitation model to the development of the isotopic composition of porous solids to derive an apparent rate constant that decays with inverse time, similar to that calculated for diagenesis in deep-sea sediments. This paper provides a theoretical framework for understanding the changing and varied dissolution and precipitation rates measured in the laboratory and in nature, and provides testable quantitative models that capture the aging effect.
Crystallization behavior and effect of thermal treatment on fracture performance of glass flake reinforced polypropylene

In this work, the role of the interface and matrix morphology in determining the fracture behavior of glass flake reinforced polypropylene is investigated. Differential scanning calorimetric analysis shows that silane coupling agent modifies the crystallization behavior of the polypropylene matrix. Silane treated glass flakes prepared by dry blending are found to induce nucleation and decrease the rate of development of the crystalline entities during the crystallization process. This effect is attributed to the physisorbed layer of silane on the glass flakes. The effect of matrix morphology on the fracture performance is analyzed by fracture mechanics. An increase in matrix crystallinity in pure polypropylene and in glass flake/polypropylene composites leads to a reduction in the maximum crack growth resistance. The lower ductility of a more crystalline matrix results in a reduction of the energy dissipated in the matrix stretching and, therefore, a concomitant decrease in the fracture energy. Although the effect of matrix morphology seemed to be important in the case of pure polypropylene and untreated glass flake polypropylene composites, this effect is found to be negligible for the silane treated composites. Nevertheless, microscopic observation of the fracture surfaces of silane treated composites also revealed a reduction in the ductility of the matrix in highly crystalline samples. An improvement in the matrix-filler interface seems to inhibit the effect of matrix morphology on the fracture behavior of glass flake/polypropylene composites.
Statistical methods for a theory of cue learning

A theory of cue learning, which gives rise to a system of recurrent events in Feller's sense, is analyzed mathematically. The distribution of total errors and sampling distribution of mean errors are derived, and the learning curve is investigated. Maximum likelihood estimates of parameters and sampling variances of those estimates are derived. Likelihood ratio tests of the usual null hypotheses and approximate tests of goodness of fit of substantive hypotheses are developed. The distinguishing characteristic of these tests is that they are concerned with meaningful parameters of the learning process.
Defining Traffic Flow Phases Using Intelligent Transportation Systems-Generated Data

The characteristics of traffic flow under various conditions have been studied by many. Particularly, researchers use the concept of flow phases to distinguish traffic characteristics under various conditions. In this study, a data-clustering methodology is developed to define the flow phases using continuous traffic data obtained through detectors. Such continuous data provide rich information on traffic characteristics. It is shown that between the two clustering variables, density has a more significant impact on the clustering results than speed. The fundamental relationships between traffic parameters are then analyzed based on the flow phase definition.
COST OF MUTUALISM: COMPETITION, TREE MORPHOLOGY, AND POLLEN PRODUCTION IN LIMBER PINE CLUSTERS

All aspects of a mutualism may not be optimal for the participating species. We examined possible consequences to limber pine (Pinus flexilis) from competition within reproductive multi-genet tree clusters, which come from multi-seed caches stored by Clark’s Nutcracker (Nucifraga columbiana). Limber pine occurs in three different tree growth forms. We predicted that genets within the tree-cluster growth form would have both reduced radial growth rates and lower pollen-cone whorl production relative to single-trunk and multi-trunk growth forms. We tested these predictions with three populations in the Front Range of the Colorado Rocky Mountains (USA), using ANCOVA models. Genets in clusters had reduced diameters, but similar heights and lower pollen-cone whorl production relative to same-aged genets in the other growth forms. Because seeds stored in clusters represent potential direct fitness loss to parent trees in comparison to seeds stored singly, nutcracker caching behavior may be suboptimal for limber pine at late life-history stages, thus generating a “cost of mutualism.”
RNA transcript profiling during zygotic gene activation in the preimplantation mouse embryo

Zygotic gene activation is essential for development beyond the 2-cell stage in the preimplantation mouse embryo. Based on alpha-amanitin-sensitive BrUTP incorporation, transcription initiates in the 1-cell embryo and a major reprogramming of gene expression driven by newly expressed genes is prominently observed during the 2-cell stage. Superimposed on genome activation is the development of a transcriptionally repressive state that is mediated at the level of chromatin structure. The identity of the genes that are expressed during the 1- and 2-cell stages, however, is poorly described, as are those genes involved in mediating the transcriptionally repressive state. Using the Affymetrix MOE430 mouse GeneChip set, we characterized the set of alpha-amanitin-sensitive genes expressed during the 1- and 2-cell stages, and we used Expression Analysis Systematic Explorer (EASE) and Ingenuity Pathway Analysis (IPA) to identify biological and molecular processes represented by these genes, as well as interactions among them. We find that although the 1-cell embryo is transcriptionally active, we did not detect any transcripts present on the MOE430 GeneChip set to be alpha-amanitin-sensitive. Thus, what the BrUTP incorporation represents remains elusive. About 17% of genes expressed in the 2-cell embryo are alpha-amanitin-sensitive. EASE analysis reveals that genes involved in ribosome biogenesis and assembly, protein synthesis, RNA metabolism and transcription are over-represented, suggesting that genome activation during 2-cell stage may not be as global and promiscuous as previously proposed. IPA implicated Myc and Hdac1 as candidate genes involved in genome activation and the development of the transcriptionally repressive state, respectively.
Comparison of the crystal and gas-phase structures of furan: An ab initio study

Abstract The crystal structure of furan is investigated using ab initio calculations on dimer and trimer subsets of the unit cell. The interaction energies are found to be additive with the neglected packing forces reducing the calculated interaction energies by 5 to 10%. The short CC bond length reported for the crystal structure is shown to be an artefact of the X-ray diffraction experiment.
A Study of Constant Absolute Vorticity Trajectories on Isentropic Surfaces.

Abstract It is shown that constant absolute vorticity (CAV) trajectories are more useful on isentropic surfaces than on constant pressure surfaces. A form of the vorticity equation is derived by use of Lagrangian methods. This form is similar to the Rossby form, and ordinary methods of computing CAV trajectories can be used with isentropic charts. A series of isentropic streamline charts was prepared and CAV trajectories were constructed at certain points on these charts. CAV trajectories were also constructed on 500-mb charts for the same time. 24- and 48-hr forecasts of wind direction and speed were made from CAV trajectories on both sets of charts, and verified. The results of these forecasts are treated statistically, and forecasts from CAV trajectories on isentropic charts are shown to be significantly better than similar forecasts from 500-mb charts. The effects of the divergence term of the vorticity equation are discussed qualitatively.
Survey of the Low Vision Rehabilitation Curricula in Occupational Therapy and Occupational Therapy Assistant Programs

OBJECTIVE We examined the preclinical curricular content pertaining to low vision rehabilitation (LVR) included in occupational therapy (OT) and occupational therapy assistant (OTA) programs. METHOD An e-mail survey containing questions about program structure and the extent of course material related to LVR in the curriculum was sent to directors of all accredited OT and OTA programs in the United States. RESULTS One hundred nineteen programs responded. The curricula of all but 1 program included LVR content. Twenty-four programs included a required course with a primary emphasis on LVR. Forty-four programs had faculty with advanced training in LVR or experience working in a LVR clinic. CONCLUSION Given that almost all respondent programs integrate LVR content into their required preclinical coursework, we recommend that LVR be incorporated into the Accreditation Council for Occupational Therapy Education standards so as to ensure knowledge of LVR within existing programs and enhance the quality of education in LVR.
Modulation of macrophage Fc receptor function by cytochalasin-sensitive structures☆☆☆

Abstract A quantitative rosette assay was used together with various pharmacologic probes to study the interaction between IgG-sensitized sheep erythrocytes (EIgG) and the rabbit alveolar macrophage Fc receptor. Of the pharmacologic agents examined, cytochalasins (A > E > D > B) produced the most marked inhibition of rosette formation. None of the agents consistently augmented resetting. The cytochalasin effect was not explicable by a direct effect on EIgG or by reduced macrophage adherence or viability. Cytochalasin modulating activity occurred within a few minutes and did not increase by preincubation of the monolayers with cytochalasin for up to 60 min. Cytochalasins did not disrupt preformed rosettes. The inhibitory effect of Cytochalasins B and D was reversible with washing, whereas the effect of cytochalasins A and E was not. Vinblastine and colchicine (10 −5 M only) also produced modest inhibition of rosette formation. Among the agents producing little or no inhibition of rosette formation were dibutyryl cAMP and cAMP agonists, 8-bromo cGMP and cGMP agonists, sulfhydryl-containing and sulfhydryl-reactive compounds, heparin, ethanol, and polyanions and polycations. The data suggest that cytochalasin-sensitive membrane structures, most likely microfilaments, are important in the interaction between IgG-coated particles and the macrophage Fc receptor.
Hypothesis recognition failure in conjunctive and disjunctive concept-identification tasks

While solving either a conjunctive or a disjunctive concept-identification problem, college students were asked to recognize hypothesis, stimulus, and feedback information from the immediately preceding trial. After this phase of the experiment, subjects were asked to estimate feature frequencies of occurrence and to classify old and new instances of the concept. Recognition performance was best for feedback and worst for stimulus information. Contrary to hypothesis theory, hypotheses were correctly recognized 65% of the time overall. Instances presented twice, once, and never before were classified equally well, a finding that argues against specific-instance theory. Finally, frequency estimates increased as a function of actual frequency. All obtained results support both frequency theory and dual-process theory.
Effects of environmental salinity and temperature on osmoregulatory ability, organic osmolytes, and plasma hormone profiles in the Mozambique tilapia (Oreochromis mossambicus)

The Mozambique tilapia, Oreochromis mossambicus, is capable of surviving a wide range of salinities and temperatures. The present study was undertaken to investigate the influence of environmental salinity and temperature on osmoregulatory ability, organic osmolytes and plasma hormone profiles in the tilapia. Fish were acclimated to fresh water (FW), seawater (SW) or double-strength seawater (200% SW) at 20, 28 or 35 degrees C for 7 days. Plasma osmolality increased significantly as environmental salinity and temperature increased. Marked increases in gill Na(+), K(+)-ATPase activity were observed at all temperatures in the fish acclimated to 200% SW. By contrast, Na(+), K(+)-ATPase activity was not affected by temperature at any salinity. Plasma glucose levels increased significantly with the increase in salinity and temperature. Significant correlations were observed between plasma glucose and osmolality. In brain and kidney, content of myo-inositol increased in parallel with plasma osmolality. In muscle and liver, there were similar increases in glycine and taurine, respectively. Glucose content in liver decreased significantly in the fish in 200% SW. Plasma prolactin levels decreased significantly after acclimation to SW or 200% SW. Plasma levels of cortisol and growth hormone were highly variable, and no consistent effect of salinity or temperature was observed. Although there was no significant difference among fish acclimated to different salinity at 20 degrees C, plasma IGF-I levels at 28 degrees C increased significantly with the increase in salinity. Highest levels of IGF-I were observed in SW fish at 35 degrees C. These results indicate that alterations in gill Na(+), K(+)-ATPase activity and glucose metabolism, the accumulation of organic osmolytes in some organs as well as plasma profiles of osmoregulatory hormones are sensitive to salinity and temperature acclimation in tilapia.
Molecular‐Orbital Studies of Hydrogen Bonds. An Ab Initio Calculation for Dimeric H2O

The hydrogen‐bond energy and the most stable structure of the dimeric H2O system are calculated by the LCAO MO SCF method using a medium‐sized Gaussian orbital basis set. The most stable structure, found by a limited variation of the interatomic coordinates, is a linear hydrogen bond (stabilization energy 12.6 kcal mole−1) with an H···O distance of 1.72 A, and with the hydrogen‐acceptor molecule almost freely rotating around its molecular axis. The stretching of the proton donor O–H bond is calculated to be 0.12 A. A population anaysis near the energy minimum shows that the change in the population is distributed not only in the O···H–O fragment, but also delocalized into the neighboring O–H bonds. Hydrogen bonds of dimeric H2O other than the linear structure (cyclic and bifurcated) are also examined.
Fast search in main memory databases

The objective of this paper is to develop and analyze high performance hash based search methods for main memory databases. We define optimal search in main memory databases as the search that requires at most one key comparison to locate a record. Existing hashing techniques become impractical when they are adapted to yield optimal search in main memory databases because of their large directory size. Multi-directory hashing techniques can provide significantly improved directory utilization over single-directory hashing techniques. A multi-directory hashing scheme, called fast search multi-directory hashing, and its generalization, called controlled search multi-directory hashing, are presented. Both methods achieve linearly increasing expected directory size with the number of records. Their performance is compared to existing alternatives.
Cutting of Single-Walled Carbon Nanotubes by Ozonolysis

Cutting of single-walled carbon nanotubes (SWNT) has been achieved by extensive ozonolysis at room temperature. Perfluoropolyether (PFPE) was selected as a medium for cutting SWNT due to its high solubility for ozone (O3). A mixture of 9 wt % of O3 in O2 was bubbled through a homogeneous suspension of pristine SWNT in PFPE, at room temperature. The intense disorder mode in the Raman spectra of ozonated SWNT indicates that extensive reaction with the sidewalls of SWNT occurs during ozonolysis. Atomic force microscopy (AFM) images of SWNT, before and after ozonolysis, provided a measure of the extent of the cutting effects. Monitoring of the evolved gases for both pristine and purified SWNT indicates CO2 was produced during the ozonolysis process with a dependence on both system pressure and temperature. During heating, FTIR analysis of gases released indicated that carbon oxygen groups on the sidewalls of SWNT are released as CO2. SWNT was found to be extensively cut after an ozone treatment with a yield o...
Rapid detection and identification of methicillin-resistant Staphylococcus aureus directly from positive blood cultures exhibiting gram-positive cocci in clusters

Abstract The rapid detection and identification of nosocomial or community-associated methicillin-resistant Staphylococcus aureus (MRSA) infection, especially bacteremia, is crucial to patient management and institution of infection control measures. In this study, we performed direct tests for coagulase and PBP2a from centrifuged aliquots of blood from BACTEC blood culture bottles showing gram-positive cocci in clusters, morphologically resembling staphylococci. Concomitantly, direct susceptibility tests were performed for cefoxitin and clindamycin resistance (D test). All test results were compared to those obtained after 24-h growth of the Staphylococcus species on agar media. Of 80 positive blood cultures, 32 were MRSA (coagulase positive, PBP2a positive, cefoxitin resistant), 17 MSSA (coagulase positive, PBP2a negative, cefoxitin susceptible), and 31 coagulase-negative staphylococci (CNS). Of the last, 12 were positive for PBP2a. Direct identification of MRSA was achieved within 4 h as contrasted to the 24 h required by the standard laboratory protocol. Inclusion of coagulase testing along with PBP2a allowed differentiation of CNS from MRSA.
Health Effects of Ozone Critical Review Discussion Papers

The A&WMA Critical Review entitled "Health Effects of Ozone" was presented by Morton Lippmann, Deputy Director of the Institute of Environmental Medicine at New York University Medical Center. Dr. Lippmann presented his review at the 82nd Air & Waste Management Association Annual Meeting and Exhibition, held in Anaheim, California in June 1989. The Critical Review paper, published in the May 1989 issue of JAPCA, provides a detailed evaluation of the available exposure, epidemiological, physiological and cellular data concerning the health effects of ozone on man and laboratory animals. Prepared discussions presented during the Critical Review session in Anaheim are published here, along with some closing remarks by Dr. Lippmann. Ronald Harkov, Chairman of the Critical Review Subcommittee of the Publications Committee, served as moderator of the 1989 A&WMA Critical Review session.
Modification of prenatal stress effects in rats by dexamethasone and adrenocorticotrophin.

Abstract To determine if effects of prenatal stress on offspring are mediated by the maternal pituitary-adrenocortical (PAC) system, female rats were stressed during gestation while manipulating their PAC output and the growth and behavior of their offspring examined. Specifically, females were injected with ACTH, dexamethasone (DEX), or saline (SAL) during pregnancy or were untreated (CON). Half the females in each group received daily electric shock sessions from Day 7 to Day 21 of gestation. Significantly more females in the ACTH and SAL groups delivered their litters late. Although DEX produced a significant reduction in birth and weaning weights of offspring whereas ACTH did not, both DEX and ACTH blocked the increase in birth weights produced by prenatal stress in offspring of SAL treated females. However, the significant effect of stress on mortality from birth to weaning was potentiated by ACTH and mortality was increased by either DEX or ACTH alone (compared to SAL). In addition, ACTH reversed the effect of stress on open-field activity of 86–96 day old offspring: stress reduced activity of SAL offspring but increased that of ACTH offspring. DEX itself significantly increased activity of female, but not male, offspring and ACTH significantly decreased activity of unstressed offspring of both sexes. Open-field behavior of 32–38 day offspring and active and passive avoidance conditioning of 86–96 day offspring were unaffected by prenatal drug or stress treatments. Attenuation of the maternal PAC response to stress consistently blocks the effects of prenatal stress on birth weights of offspring but can potentiate, reverse, or fail to modify the effects of stress on behavior. It thus seems unlikely that prenatal stress effects on offspring behavior are mediated by the maternal PAC system.
Focal and bidirectional modulation of lower limb motor cortex using anodal transcranial direct current stimulation

Background Because we are interested in noninvasive transcranial brain stimulation as an adjuvant to poststroke walking therapy, we applied transcranial direct current stimulation (tDCS) preferentially to either the left or right lower limb motor cortex (M1) in two separate sessions and assessed the resulting modulation in both cortices. Objective We hypothesized that tDCS applied preferentially to one lower limb M1 of healthy subjects would induce between-hemisphere opposite sign modulation. Methods Transcranial magnetic stimulation (TMS) with the coil offset 2cm either side of vertex was used to assess the percentage of change in the rectified motor-evoked potential (MEP) area recorded bilaterally from the vastus lateralis (VL) and tibialis anterior (TA) of 10 subjects during weak tonic contraction. Results Analysis of variance (ANOVA) revealed an up-regulation of the target cortex and a down-regulation of the nontarget cortex ( P =.001) and no effects of hemisphere (left, right) or muscle (TA, VL). Significant modulation was evident in 78% of VL and TA muscles (all P increased in 60%, but decreased in 18%. For 43% when excitability increased, a simultaneous decrease in excitability was evident in homologous muscle responses providing support for our hypothesis. Conclusions The results indicate a modest effectiveness and focality of anodal tDCS when applied to lower limb M1, suggesting in a human model that the strength and depth of polarizing cortical currents induced by tDCS likely depend on interindividual differences in the electrical properties of superficial brain structures.
The museum experience revisited

Over 20 years ago, The Museum Experience by John Falk and Lynn Dierking (1992) entered the literature as one of the first museum books to offer a framework that describes the visitor's experience. ...
Selective sulfonation of a secondary hydroxyl group of β-cyclodextrin

Abstract Tosylation of the secondary side of β-cyclodextrin, which has previously been incorrectly reported, can be achieved by tosyl transfer from 3-nitrophenyl toluenesulfonate to the C-2 hydroxyl of the cyclodextrin.
The world of Islam: a political overview

(1990). The world of Islam: a political overview. Institute of Muslim Minority Affairs. Journal: Vol. 11, No. 2, pp. 218-225.
Surface structures of supported tungsten oxide catalysts under dehydrated conditions

The molecular structures of the WO3/support (Al2O3, TiO2, Nb2O5, ZrO2, SiO2, and MgO) catalysts under in situ dehydrated conditions have been investigated by Raman spectroscopy. The series of catalysts was synthesized by the aqueous incipient wetness method. The WO3/support catalysts, with the exception of the WO3SiO2 and WO3MgO catalysts, possess a highly distorted, octahedrally coordinated surface tungsten oxide species with one short WO bond (mono-oxo tungsten oxide species) at high surface coverages. The WO3SiO2 catalysts exhibit strong Raman features of crystalline WO3 particles due to the relative low density and reactivity of the surface hydroxyl groups. The WO3MgO catalysts possess non-stoichiometric compounds, Mgx(WO4)y and Cax(WO4)y, at low tungsten oxide contents and crystalline MgWO4 and CaWO4 at high tungsten oxide contents. This result is attributed to the high aqueous solubility of MgO as well as the CaO impurity and the strong acid-base interaction between WO2−4 with Mg(OH)2 and Ca(OH)2. The current findings for supported tungsten oxide catalysts parallel the previous findings for supported molybdenum oxide catalysts and reflect the similar surface structural chemistry of these two oxides.
Two new bicyclic ring systems, 1,4,5-benzodioxazocine and 1,4-benzoxazepine.

Derivatives of two new bicyclic ring systems have been synthesized for pharmacological evaluation as central nervous system drugs. These derivatives were 7-chloro-5-phenyl-2,3,4,5H-1,4-benzoxazepine hydrochloride (I), 7-chloro-5-phenyl-2,3H-I,4-benzoxazepine-4-oxide (II), and 8-chloro-6-phenyl-2,3H-1,4,5- benzodioxazocine (III). The synthetic routes leading to these structures are presented.
Disengagement predictions via drift flux correlation vertical, horizontal and spherical vessels

The behavior of an open system is modeled. Thus, for special cases, the void fraction is predicted as a function of location and time. The open system may be an open vessel or a vessel with an open relief device. A single governing equation is derived based on combining the material and energy balances with the churn-turbulent drift flux relationship and assuming no radial gradients. This partial differential equation is not solved. It is, however, bounded by homogeneous and all vapor venting. These special cases are solved. In homogeneous venting the key variable is time. In all vapor venting under pseudo-steady-state conditions the key variable is location. The solution of the partial differential equation is also discussed. Under pseudo-steady-state and churn-turbulent conditions, the open system is modeled. The minimum void fractions (corresponding to a maximum liquid inventory) with all vapor venting, for vertical, horizontal, and spherical vessels are predicted and compared. Analytical expressions for the local and average void fractions in a vertical vessel and non-unity distribution parameters are presented. Void fraction profiles are compared for three cases: 1. vertical cylinders with distribution parameters (Co values) of unity and 1.5, 2. horizontal and vertical cylinders with varying L/D ratios, and 3. spheres with inscribed vertical cylinders having constant gas production to bubble rise ratio (Ψ′ value). The vertical cylinder average void fraction for non-unity distribution parameters can now be calculated analytically. The horizontal cylinder average void fraction predicted by turning it upright results in an over prediction of at most 4%. The sphere average void fraction predicted via an inscribed vertical cylinder, with the same Ψ′ value, is consistenly high by at most 8%.
Self-similarity and long range dependence on the internet: a second look at the evidence, origins and implications

In this paper we critically reexamine some of the long standing beliefs regarding self-similarity and long range dependence (LRD) on the Internet. Power law tails have been conjectured to be a cause of LRD. In this paper, we reexamine the claims regarding heavy tails. We first examine the generative models for the heavy tail phenomena, both in terms of the fragility of some proposed mechanisms to modeling perturbations as well as the weak statistical evidence for the mechanisms. Next, we take a look at some of the implications of LRD in key performance aspects of Internet algorithms. Finally, we present an alternative model explaining the LRD phenomena of Internet traffic. We argue that the multiple time-scale nature of the generation of traffic and transport protocols make the observation of LRD inevitable.
Comparison of auditory stimulus processing in normal and autistic adolescents

This experiment investigated the possibility that autistic adolescents may avoid speech communication with the world around them by “tuning out” or perceptually suppressing auditory speech stimuli. The tune-out auditory supression hypothesis was investigated using the subject's own speech as the stimulus under three perceptual-motor conditions: (1) with speech in a delayed auditory feedback (DAF) mode, (2) with a white noise masking speech mode, and (3) with speech in a normal, quiet listening mode. Five autistic adolescents were compared with six normal controls on speech time duration and sound level. DAF increased the speech sound pressure level (SPL) and increased speech time duration for both groups.
Surgical resection in disseminated testicular cancer following chemotherapeutic cytoreduction

Platinum combination chemotherapy will regularly produce a 70% complete response rate in testicular cancer. Many patients failing to achieve complete remission can still be rendered disease-free with surgical resection of residual localized disease. Twenty-one patients underwent resection for residual pulmonary lesions and 41 underwent lymphadenectomy for persistent retroperitoneal disease. There were no characteristic radiographic findings for fibrous tissue versus mature teratoma versus carcinoma. Although elevated HCG or AFP levels indicated the presence of carcinoma, negative HCG and AFP did not rule out such a diagnosis as 12 of 22 resected carcinoma patients were seronegative. Of 35 patients, 31 (89%) with fibrous tissue or mature teratomas and all four patients with immature teratomas have been continuously free of disease with a minimal postoperative follow-up time of six months. However, only two of 22 patients with resected carcinomas have been continuously disease-free. Post-operative chemotherapy for mature teratoma or fibrous tissue is probably not necessary. However, we feel that further aggressive chemotherapy is needed in the resected carcinoma patient with at least two courses of platinum combination chemotherapy. Surgical resection of residual disease following chemotherapy-induced cytoreduction with platinum combination chemotherapy may be therapeutic in some cases and helps to define the optimal subsequent treatment strategy.
Transcriptional regulation of rat CYP2A3 by nuclear factor 1: Identification of a novel NFI-A isoform, and evidence for tissue-selective interaction of NFI with the CYP2A3 promoter in vivo

Rat CYP2A3 and its mouse and human orthologs are expressed preferentially in the olfactory mucosa. We found previously that an element in the proximal promoter region of CYP2A3 (the nasal predominant transcriptional activating (NPTA) element), which is similar to a nuclear factor 1 (NFI)-binding site, is critical for transcriptional activation of CYP2A3 in vitro. We proposed that this element might be important for tissue-selective CYP2A3 expression. The goals of the present study were to characterize NPTA-binding proteins and to obtain more definitive evidence for the role of NFI in the transcriptional activation of CYP2A3. The NPTA-binding proteins were isolated by DNA-affinity purification from rat olfactory mucosa. Mass spectral analysis indicated that isoforms corresponding to all four NFI genes were present in the purified NPTA-binding fraction. Further analysis of NPTA-binding proteins led to the identification of a novel NFI-A isoform, NFI-A-short, which was derived from alternative splicing of the NFI-A transcript. Transient transfection assay showed that NFI-A2, an NFI isoform previously identified in the olfactory mucosa, transactivated the CYP2A3 promoter, whereas NFI-A-short, which lacks the transactivation domain, counteracted the activation. Chromatin immunoprecipitation assays indicated that NFI proteins are associated with the CYP2A3 promoter in vivo, in rat olfactory mucosa, but essentially not in the liver where the CYP2A3 promoter is hypermethylated and CYP2A3 is not expressed. These data strongly support a role for NFI transcription factors in the transcriptional activation of CYP2A3.
A monoclonal antibody (BMA-1) reactive with murine B cells as well as resident and elicited but not activated macrophages

Abstract Hybridoma technology has been employed to prepare a monoclonal antibody that recognizes a sub-population of mononuclear leukocytes. Enzyme-linked immune assay revealed a cell clone producing a monoclonal antibody reactive with elicited but not activated C57Bi/6 peritoneal macrophages. Detailed analyses using fluorescence flow cytometry demonstrated that this monoclonal antibody binds to B cells, B cell blasts, as well as to the resident and elicited macrophages, but not to activated macrophages, T cells, red blood cells, or syngeneic fibroblasts. This antigen has been designated BMA-1. Antigenic expression is greatest upon resident macrophages. A bimodal level of expression is found on elicited macrophages while activated macrophages possess low levels of expression. The unique cellular distribution of this antigen indicates that it is lost during macrophage differentiation to the activated state. Immunoprecipitation studies indicate that this antigen is composed of multiple subunits; the primary subunit possesses a molecular weight of 38,000. This new tool should be valuable in the analysis of heterogeneous macrophage populations and in defining molecular differentiation pathways.
Electrostrain measurements of PLZT with slim P-E and s-E loops

Abstract PLZT(9/65/35) ceramics were manufactured by partially coprecipitate methods with several combinations between nitrates and oxides. Compositions, grain forms and grain sizes were compared between products by various calcination process. The best performanced ceramics were obtained from lead nitrate, lantanium nitrate, zirconium oxide and titanium oxynitrate with 1.22μm in grain size and 0.98 μm in its standard deviation, and showed 0.67 × 10−−9 m/V of the electrostrain coefficient d-value.
Effect of borohydride reduction on antibodies.

The effect of borohydride reducing reagents on monoclonal and polyclonal antibodies was examined by enzyme-linked immunosorbent assay (ELISA). Each antibody showed different stability characteristics to the reducing reagents. Sodium cyanoborohydride was at least five times milder toward immunological activity than sodium borohydride, however, sodium cyanoborohydride with a catalytic amount of metal ion (Zn2+ or Al3+ ) can be as harsh as sodium borohydride. Activated hydrophobic borohydrides, 9BBN-pyridine, did not have any advantages in respect to the stabilities of antibodies. Antibodies to be used for immunosorbent purification must be evaluated individually to determine whether their structure is stable to immobilization reagents and conditions prior to their linkage to the column support.
Tumors are unique organs defined by abnormal signaling and context.

Many cancer investigations have focussed on the eradication of the cancer cell itself and in doing so, overlook the inherent complexity and heterogeneity of solid tumors. Here, we argue that, in many cases, it is the altered communication within the tumor, rather than mutations per se, that is the defining characteristic of cancer. As a result, tumorigenesis can be indirectly initiated by environmental or inherited factors that affect the stromal cells. We propose that anticancer research might be more effective if aimed at eradicating the cause of abnormality rather than just treating the end result.