cssi/SciSciGPT-SciSciNet huggingface dataset:
Os livros didáticos de Ciências na Escola Secundaria Brasileira: 1900 a 1950

Nos artigos de Lorenz e Barra e Lorenz foram apresentadas informacoes sobre os livros e materiais didaticos de ciencias utilizadas na escola secundaria brasileira de 1900 a 1950 e de 1950 a 1970, respectivamente. A falta de dados disponiveis sobre o ensino de ciencias na escola secundaria publica desde sua fundacao oficial em 1837 tornou estes trabalhos valiosos por permitir um estudo dos conteudos desenvolvidos em sala de aula e de orientacao dada aos mesmos naqueles periodos.
Control of myosin heavy chain expression in cardiac hypertrophy

The control of myosin expression by thyroid hormone is analyzed as an example of compensatory mechanisms of the heart. Two topics are discussed in detail: polymorphism of cardiac myosin heavy chains in the mammalian heart, and effect of thyroid hormone on myosin heavy chain expression by thyroid hormone. Our current knowledge about the identity of heavy chains and their corresponding isomyosins myosins is summarized and the dynamic nature of the myosin phenotype of the heart is discussed. The data on the thyroid hormone's role include studies in which the synthesis rate of the 2 classes of heavy chains (alpha and beta) was compared with their respective messenger RNA levels. A close correlation was observed and is consistent with pretranslational control. Transcription of myosin heavy chain genes was examined using isolated nuclei in a run-off experiment The rate of gene transcription was found to be the principal determinant of the cytoplasmic level of messenger RNA and of the isomyosin composition of the heart.
Crystal structure of (E)-13-{4-[(Z)-2-cyano-2-(3,4,5-tri-meth-oxy-phen-yl)ethen-yl]phen-yl}parthenolide methanol hemisolvate.

The title compound, C33H35NO6 [systematic name: (Z)-3-(4-{(E)-[(E)-1a,5-dimethyl-9-oxo-2,3,7,7a-tetra­hydro­oxireno[2′,3′:9,10]cyclo­deca­[1,2-b]furan-8(1aH,6H,9H,10aH,10bH)-yl­idene]meth­yl}phen­yl)-2-(3,4,5-tri­meth­oxy­phen­yl)acrylo­ni­trile methanol hemisolvate], C33H35NO6·0.5CH3OH, was prepared by the reaction of (Z)-3-(4-iodo­phen­yl)-2-(3,4,5-tri­meth­oxy­phen­yl)acrylo­nitrile with parthenolide [systematic name: (E)-1a,5-dimethyl-8-methyl­ene-2,3,6,7,7a,8,10a,10b-octa­hy­dro­oxireno[2′,3′:9,10]cyclo­deca­[1,2-b]furan-9(1aH)-one] under Heck reaction conditions. The mol­ecule is built up from fused ten-, five- (lactone) and three-membered (epoxide) rings with a {4-[(Z)-2-cyano-2-(3,4,5-tri­meth­oxy­phen­yl)ethen­yl]phen­yl}methyl­idene group as a substituent. The 4-[(Z)-2-cyano-2-(3,4,5-tri­meth­oxy­phen­yl)ethen­yl]phenyl group on the parthenolide exocyclic double bond is oriented in a trans position to the lactone ring to form the E isomer. The dihedral angle between the benzene ring of the phenyl moiety and the lactone ring mean plane is 21.93 (4)°.
THE ROLE OF THEORY IN GEOGRAPHICAL INQUIRY

(1961). THE ROLE OF THEORY IN GEOGRAPHICAL INQUIRY. The Professional Geographer: Vol. 13, No. 2, pp. 1-6.
Hybrid ape offspring of a mating of gibbon and siamang

The serendipitous mating of a male gibbon, Hylobates moloch, and a female siamang, Symphalangus syndactylus, has produced two female offspring born 1 year apart. The hybrid karyotype of 47 chromosomes comprises the haploid complements of the parental species, 22 for the gibbon and 25 for the siamang. Chromosomal G and C banding comparisons revealed no clear homologies between the parental karyotypes except for the single chromosome in each species containing the nucleolus organizer region. The lack of homology suggests that the structural rearrangement of chromosomes has played a major role in the process of speciation for these lesser apes.
Idea clarification: A matter of predesign

If one's ideas register clearly with listeners, the primary goal of speaking has been realized. Guided by selected principles of learning, a speaker can plan the content of his message so that listeners can more completely understand the intended meaning. In this discussion, Che providing of idea clarification is correlated with the promoting of learning for listeners. Ten principles of learning are characterized. Random effort by the speaker can be replaced by purposeful, advance design in the speaker's presentation in order to establish clarity for ideas.
CSR Infrastructure for Communication and the Nike Controversy

Where most literature explains Corporate Social Responsibility (CSR) communication through Resource Dependency and Institutional Theories, this study investigates how the emergence and maintenance of an infrastructure for communication influences organizational communicative behavior. The infrastructure for communication is a repertoire of materials that act as a tacit framework for the preferred forms of communicative strategy and instrumentation among a community of organizations. This is a longitudinal study of the controversy surrounding Nike’s supply chain from 1993 to 2004. To draw conclusions about the nature of an infrastructure requires a form of analysis known as infrastructural inversion, which is a reflective practice that involves assessing the communication and interaction of actors to ascertain the relevant patterns that impact behavior. The main finding of the study is that infrastructure shaped how the organizations behaved by acting as a coordinating device for the symbolic and material qualities of inter-organizational communicative strategy and instrumentation.
Simulation of energetic particle injections associated with a substorm on August 27, 2001

[1] Discrete injections of energetic electrons and ions and their subsequent drift echoes were observed shortly after 0410 UT on August 27, 2001 by three geosynchronous satellites which were arrayed on the dayside. The GOES-8 spacecraft at geosynchronous orbit near local midnight, the four-satellite CLUSTER constellation also near local midnight. Concurrent and POLAR was at two hours after midnight. The observations from this suite of satellites provide the basis of information and constraints for us to model the particle injections. The simulations with test-particle simulations, reproduce both the observed electron and ion injections and subsequent drift echoes. Our simulation results support the idea that the energetic particle injections into the inner magnetosphere are a consequence of near-Earth magnetic reconnection.
A dual effect of sodium on oxygen consumption in toad bladder.

Abstract 1. 1. Q O 2 measured in a Warburg respirometer was found to be stimulated by the addition of external Na+. The relationship between extra Q O 2 and the concentration of Na+ displays saturation kinetics, the maximal effect occurring at 40–60 mM. 2. 2. 2,4-Dinitrophenol stimulated Q O 2 and inhibited the short-circuit current (s.c.c.). The maximally effective concentration of dinitrophenol was the same for both, 5·10−5–10·10−5M. 3. 3. The addition of Na+ (40 mM) in the presence of dinitrophenol (1·10−4M) produced a further marked stimulation of Q O 2 . The effects of varying the concentration of dinitrophenol on this Na+-independent Q O 2 paralleled the effects on s.c.c. and Na+-independent Q O 2 . 4. 4. The results are interpreted as showing a direct stimulation of the respiratory chain by Na+per se.
A DESCRIPTIVE AND ULTRASTRUCTURAL STUDY OF THE GREEN ALGA, CHLAMYDOMONAS DESMIDII SP. NOV. (VOLVOCALES. CHLAMYDOMONADACEAE) FROM ROCKY MOUNTAIN NATIONAL PARK LAKES

The green algal flagellate Chlamydomonas desmidii sp. nov., is described from several lakes in Rocky Mountain National Park, Colorado. The biflagellate cells generally have an hour-glass shape. They possess a single chloroplast with two pyrenoids and a superficial stigma near the center of the cell. Numerous contractile vacuoles occur in the Peripheral cytoplasm and they are arranged in several rings around the nucleus in the constricted region of the cell. Ultrastructural studies verify these features and elaborate upon the structure of the cell.
Restrictive red blood cell transfusion: not just for the stable intensive care unit patient.

Abstract Background Multiple studies report that patients receiving red blood cell (RBC) transfusion in the intensive care unit (ICU) are more likely to experience complications. Despite these findings, surgical patients are frequently transfused for operative procedures, trauma, and burns. We hypothesized that a RBC transfusion guideline would safely decrease our use of RBC transfusions in the ICU and lower the hematocrit at which our trauma and burn patients were transfused, both in the stable and symptomatic patient. Methods For each episode of RBC transfusion, the pretransfusion vital signs and reasons for transfusion were recorded prospectively from August 2003 through April 2004. Before institution of the transfusion guideline, which stressed withholding transfusion for hematocrit over 23 in asymptomatic patients, intensive education of all caregivers occurred. Data from all transfusions during 2005 were also reviewed for long-term compliance with the guideline. Results Eighty-two of 316 ICU patients (26%) had 315 RBC transfusion events during the initial study period. Mean transfusion hematocrits decreased from 26.6 ± 4.7 to 23.9 ± 2.6 (P Conclusion A transfusion guideline accompanied by intensive education is effective in reducing RBC transfusions in a trauma-burn ICU. A lower hematocrit was well tolerated in both the symptomatic and asymptomatic groups of surgical patients. With education and follow-up, the changes in transfusion practices were durable and affected transfusion practices for both asymptomatic and symptomatic patients.
Hydrodynamic and Thermal Boundary Layers Over a Flat Plate With Slip Flow and Constant Surface Heat Flux

In this paper the boundary layer flow over a flat plat with slip flow and constant heat flux surface condition is studied. Because the plate surface temperature varies along the x direction, the momentum and energy equations are coupled due to the presence of the temperature gradient along the plate surface. This coupling, which is due to the presence of the thermal jump term in Maxwell slip condition, renders the momentum and energy equations non similar. As a preliminary study, this paper ignores this coupling due to thermal jump condition so that the self-similar nature of the equations is preserved. Even this simplified problem for the case of a constant heat flux boundary condition has remained unexplored in the literature and was therefore chosen for study in this paper. For the hydrodynamic boundary layer, velocity and shear stress distributions are presented for a range of values of the parameter characterizing the slip flow. This slip parameter is a function of the local Reynolds number, the local Knudsen number, and the tangential momentum accommodation coefficient representing the fraction of the molecules reflected diffusively at the surface. As the slip parameter increases, the slip velocity increases and the wall shear stress decreases. These results confirm the conclusions reached in other recent studies. The energy equation is solved to determine the temperature distribution in the thermal boundary layer for a range of values for both the slip parameter as well as the fluid Prandtl number. The increase in Prandtl number and/or the slip parameter reduces the dimensionless surface temperature. The actual surface temperature at any location of x is a function of the local Knudsen number, the local Reynolds number, the momentum accommodation coefficient, Prandtl number, other flow properties, and the applied heat flux.Copyright © 2008 by ASME
Metnase/SETMAR: a domesticated primate transposase that enhances DNA repair, replication, and decatenation

Metnase is a fusion gene comprising a SET histone methyl transferase domain and a transposase domain derived from the Mariner transposase. This fusion gene appeared first in anthropoid primates. Because of its biochemical activities, both histone (protein) methylase and endonuclease, we termed the protein Metnase (also called SETMAR). Metnase methylates histone H3 lysine 36 (H3K36), improves the integration of foreign DNA, and enhances DNA double-strand break (DSB) repair by the non-homologous end joining (NHEJ) pathway, potentially dependent on its interaction with DNA Ligase IV. Metnase interacts with PCNA and enhances replication fork restart after stalling. Metnase also interacts with and stimulates TopoIIα-dependent chromosome decatenation and regulates cellular sensitivity to topoisomerase inhibitors used as cancer chemotherapeutics. Metnase has DNA nicking and endonuclease activity that linearizes but does not degrade supercoiled plasmids. Metnase has many but not all of the properties of a transposase, including Terminal Inverted Repeat (TIR) sequence-specific DNA binding, DNA looping, paired end complex formation, and cleavage of the 5′ end of a TIR, but it cannot efficiently complete transposition reactions. Interestingly, Metnase suppresses chromosomal translocations. It has been hypothesized that transposase activity would be deleterious in primates because unregulated DNA movement would predispose to malignancy. Metnase may have been selected for in primates because of its DNA repair and translocation suppression activities. Thus, its transposase activities may have been subverted to prevent deleterious DNA movement.
Omnibenevolence and eternal damnation

In “Omnibenevolence and Eternal Damnation”, I consider whether it is consistent to hold both that God is omnibenevolent and that he infinitely punishes human beings for the commission of finite transgressions. In exploring this problem, I discuss the utilitarian and retributive notions of punishment and justice, the possible mitigating effect of forewarning, and differing conceptions of the nature of the relationship of God to human beings. My conclusion is that it is inconsistant to hold both of these beliefs.
Hot-electron degradation of n-channel polysilicon MOSFETs

The stability of the hydrogen passivation in hydrogenated n-channel polysilicon MOSFETs has been studied under thermal stress and hot-electron stress at elevated temperatures. Although the hydrogen passivation is stable at 150 degrees C, channel hot-electron stress at high temperatures appears to create additional grain boundary traps, presumably by breaking the Si-H bonds at the grain boundaries. This mechanism is in addition to the creation of acceptor-type fast interface states that occur in bulk MOSFETs. >
Evaluation of the vervet (Clorocebus aethiops) as a model for the assisted reproductive technologies.

The vervet monkey was evaluated as a primate model for use in assisted reproductive technologies (ARTs). Eight adult female vervets were hormonally monitored for their potential use as egg donors and those six females displaying regular menstrual cycles were subjected to controlled ovarian stimulation with recombinant human gonadotropins. Three animals failed to respond while laparoscopic follicular aspiration was performed on the other three females at 27–30 h post-human chorionic gonadotropin administration. A total of 62, 40, and 18 oocytes was recovered from these three animals of which 30, 20, and 4, respectively, matured to the metaphase II stage and were subsequently inseminated using intracytoplasmic sperm injection. An average of 40±15% (SEM) of the inseminated oocytes were fertilized based on pronucleus formation and timely cleavage. One embryo from each of the two stimulated females developed into expanded blastocysts. Two adult male vervets were assessed as sperm donors. Neither adjusted well to the restraint and collection procedure required for penile electroejaculation. Samples collected via rectal electroejaculation were very low in sperm motility and concentration; however, cauda epididymal aspirations from one male yielded an adequate concentration of motile sperm. These results emphasize the need to establish species-specific ovarian stimulation protocols and semen collection techniques if vervets are to be considered for basic and applied (ARTs) research on primate gametes or embryos. Am. J. Primatol. 69:917–929, 2007. © 2007 Wiley-Liss, Inc.
A small volume microcalorimeter for analytical determinations

Abstract A new design in microcalorimeters utilizing a unique detector configuration that gives good sensitivity and rapid analysis time is described. The detector is capable of sensing less than 5 mcal without additional amplification and uses only small (10–100 μl) volumes of sample. Application to several inorganic, organic, and biochemical reactions are given. The advantages of heat-sensing instrumentation with respect to analytical determinations are augmented by the rapidity of operation of the described instrumentation.
The heterogeneity of isolated adult rat Leydig cells separated on Percoll density gradients: an immunological, cytochemical, and functional analysis

Intertubular cells, isolated from adult rat testes by collagenase dispersal under conditions designed to minimize cell damage, were fractionated on Percoll density gradients. In the gradient fractions, there was a close cellular correlation between the presence of 3 beta-hydroxysteroid dehydrogenase (3 beta HSD), determined by cytochemistry, and other Leydig cell markers (nonspecific esterase, autofluorescence, and an antigen defined by monoclonal antibody LC-1C6). As the reagents for 3 beta HSD cytochemistry are excluded by intact membranes, Leydig cells with damaged plasma membranes were identified by 3 beta HSD reactivity in suspended cell preparations, and the total number of 3 beta HSD-positive (3 beta HSD+) cells in the same preparations was determined after lysis of the cell membrane. Whole cells were differentiated from cytoplasmic fragments by counterstaining with the nuclear dye propidium iodide, and the number of intact Leydig cells in each preparation was determined subsequently by subtracting the number of damaged nucleated 3 beta HSD+ cells from the total number of nucleated 3 beta HSD+ cells. The majority of intact isolated Leydig cells were found in gradient fractions of 1.054-1.096 g/ml density. Acute (3-H) basal and hCG-stimulated testosterone production per intact Leydig cell were dependent upon the concentration of Leydig cells per assay well, indicating that there is cooperativity among Leydig cells in vitro. There was no difference in steroidogenic function among intact Leydig cells from different fractions of the above density gradient range at assay concentrations greater than 10,000 Leydig cells/well. At lower cell concentrations, Leydig cells from gradient fractions of lower density (1.054-1.064 g/ml) produced slightly less testosterone in response to hCG stimulation than Leydig cells from more dense fractions (1.070-1.096 g/ml). Prolonging the exposure of isolated cells to the dispersal conditions caused declines in the apparent buoyant density and basal testosterone and hCG-stimulated cAMP and testosterone production of all Leydig cells, without detectable changes in cell integrity. The data indicate that both the absolute steroidogenic function and the functional heterogeneity of isolated intact Leydig cells are, at least in part, dependent upon the procedures used for their isolation.
The surgical learning curve for artificial urinary sphincter procedures compared to typical surgeon experience.

Abstract Background The artificial urinary sphincter (AUS) is a well-established treatment for male stress urinary incontinence. Objective We aimed to characterize the surgical learning curve for reoperation rates after AUS implantation. Design, setting, and participants The study cohort consisted of 65 602 adult males who received an AUS between 1988 and 2008, constituting close to 90% of all operations conducted during that time. Data on reoperations were obtained from the manufacturer, which requires documentation for warranty coverage. Measurements Surgeon experience was calculated as the number of original AUS implants performed prior to the index patient's surgery. Multivariable logistic regression models were used to examine the association between experience and reoperative rates, adjusted for case mix. Results and limitations There was a slow but steady decrease in reoperative rates with increasing surgeon experience ( p =0.020), showing no plateau through 200 procedures. The risk of reoperation for a surgeon with five prior cases was 24.0%, which decreased to 18.1% for a surgeon with 100 prior implants (absolute risk difference [ARD]: 5.9%; 95% confidence interval [CI], 1.3–10.1%) and to 13.2% for a surgeon with 200 prior implants (ARD: 10.7%; 95% CI, 2.6–16.6%). Two-thirds of contemporary patients (having AUS procedure between years 2000 and 2008) saw a surgeon who had done ≤25 prior AUS implants; only 9% saw a surgeon with ≥100 prior procedures. Conclusions The learning curve for AUS surgery appears to be very long and without an obvious plateau. This is in contrast to typical surgeon experience, suggesting a considerable burden of avoidable reoperations. Efforts to flatten the learning are urgently needed.
Causes of Increasing Ages at Marriage: An International Regression Study

Abstract The mean age at marriage is increasing in nearly all regions of the world, with the gender age difference at marriage tending to decrease. Five hypotheses for these trends (economic modernization, supply and demand, social/cultural/religious influences, healthcare quality, and longevity risk sharing) are tested through cross-country regression analyses of the timing and prevalence of marriage, using 40 explanatory variables from 156 countries. The dependent variables are female mean age at marriage, gender age difference, and proportion of females married by age 20-24. Ample evidence of the impact of economic modernization and education is found. The influence of cultural beliefs is evidenced by the presence of religious variables in several selected regression equations.
REST-dependent epigenetic remodeling promotes the developmental switch in synaptic NMDA receptors

Expression of GluN2 subunit of NMDA receptor (NMDAR) in rodents is developmentally regulated such that GluN2B expression is high during early postnatal period but is replaced by GluN2A in adulthood, thus conferring different NMDAR channel properties and kinetics. This study identifies a molecular mechanism for GluN2A/B switch that is mediated by the transcriptional repressor REST. This process is also shown to be affected by postnatal stress induced by maternal deprivation, leading to long-lasting effects on NMDAR-subunit composition in the hippocampus.
Serum thyroxine concentrations in the pacific hagfish and lamprey and in the leopard frog.

Abstract Concentrations of thyroxine in samples of fresh serum, measured by use of a competitive protein binding procedure, averaged 3.4 μg/100 ml in Pacific hagfish ( Eptatretus stouii ), 0.5 μg/100 ml in adult Pacific lampreys ( Entosphenus tridentatus ), and 1.7 μg/100 ml in Mexican leopard frogs ( Rana pipiens complex).
Design and construction of an electro-optic RF metamaterial array

Subwavelength metallic structures capable of creating strongly localized electromagnetic field with enormous enhancement under illumination/excitation are designed for direct radio frequency (RF) imaging. Three dimensional finite element method models are applied to investigate the electromagnetic field concentrations of two types of split ring resonators. Under appropriate linearly polarized illumination, a highly confined field located at the gap of the ring resonator is found due to strong scattering resonance. The numerical studies show that field enhancement as high as 6,800 is achieved for a planar D-shaped split ring resonator. The enhancement can be further increased through shrinking the gaps size or the ring width. Crescent shaped split ring resonator is designed for broadband application. It provides an enhanced bandwidth which is 1.15 times of the resonant frequency. The concentrated electromagnetic field facilitates nonlinear processes that find lots of applications. Optimized RF concentrators integrated with electro-optic modulators are demonstrated to directly modulate optical carrier. The combination of RF concentrator and EO modulator could enable a focal plane RF imager array that allows direct RF imaging, and significantly decrease RF aperture size and weight. Additional benefits include enhanced functionality such as inherent polarimetric imaging capability.
Use of a “kickstand” modification for external fixation of lower extremity fractures in children

Abstract Purpose To evaluate and describe the kickstand modification and its use in children with lower extremity fractures. Methods Retrospective review identified eight children in whom the kickstand technique was used during treatment of their lower extremity fractures. The seven boys and one girl had a mean age of 11.8 years. All fractures were caused by high-energy trauma. Five of the eight tibial fractures were open fractures (one type 1, one type 2, and three type 3B), and five of the eight patients had multiple extremity fractures. Results Additional procedures were required in six of the eight children, four of whom had multiple lower extremity fractures. No additional pressure-relieving modalities were used in any patient. The kickstand did not affect the fracture reduction, prevent patient mobilization, or require operative adjustment in any patient, and none had any skin pressure-related complications on the heel of the affected extremity. Conclusion In pediatric patients with lower extremity ...
S-Nitrosylation: NO-Related Redox Signaling to Protect Against Oxidative Stress

Nitric oxide (NO) plays an important role in the regulation of cardiovascular function. S-nitrosylation, the covalent attachment of an NO moiety to sulfhydryl residues of proteins, resulting in the formation of S-nitrosothiols (SNOs), is a prevalent posttranslational protein modification involved in redox-based cellular signaling. Under physiologic conditions, protein S-nitrosylation and SNOs provide protection preventing further cellular oxidative and nitrosative stress. However, oxidative stress and the resultant dysfunction of NO signaling have been implicated in the pathogenesis of cardiovascular diseases.
Supergravity from self-interaction

Abstract Supergravity is shown to be the unique consistent interacting theory of massless spin-2 plus spin-3/2 particles. It is derived from the noninteracting form using the gauge invariances intrinsic to the latter. As a preliminary, the vierbein form of general relativity is also uniquely obtained from the free spin-2 action.
Bulky disease is an adverse prognostic factor in patients treated with chemotherapy comprised of cyclophosphamide, doxorubicin, vincristine, and prednisone with or without radiotherapy for aggressive lymphoma.

BACKGROUND In the current study, the authors analyzed prognostic factors in patients with aggressive lymphoma treated with a chemotherapy regimen comprised of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) with or without radiotherapy. METHODS Between September 1988 and December 1996, 294 patients with newly diagnosed, clinical Ann Arbor Stage I-IV, aggressive lymphoma were enrolled on 2 protocols at The University of Texas M. D. Anderson Cancer Center. Patients on these studies had a relatively favorable prognosis; 100% had M. D. Anderson tumor scores ≤ 2 and 95%% had International Prognostic Indices (IPIs) ≤ 2. Treatment was comprised of 5 ± 1 (mean ± the standard deviation) cycles of CHOP chemotherapy with or without involved-field radiotherapy to a total dose of 40.1 ± 3.3 grays (mean ± the standard deviation). RESULTS The median length of follow-up was 61 months. Three factors were found to retain independent prognostic significance on multivariate analysis in terms of progression-free survival: > 1 extranodal site of disease (P 60 years (P = 0.001), bulky disease (P = 0.016), and an at least 10% elevation in the serum LDH level (P = 0.040) also were found to be independent prognostic factors for overall survival. CONCLUSIONS The independent prognostic factors in the current study suggest that either the M. D. Anderson tumor score system or the IPI can be used to select which aggressive lymphoma patients are at high risk for disease recurrence based on their having more than two adverse factors and who consequently are candidates for more intensive frontline therapy. Involved-field radiotherapy should be considered in those patients with bulky lymphomas. Cancer 2001;91:2440–60. © 2001 American Cancer Society.
Mechanism of emulsion polymerization of styrene using a reactive surfactant

The emulsion polymerization of styrene using the reactive surfactant sodium dodecyl allyl sulfosuccinate (TREM LF-40) was studied. The polymerization kinetics were found to be unusual in that Rp was not directly proportional to Np (Rp ∝ Np0.67). Several reasons are stated to explain the unusual kinetics, including chain transfer to TREM LF-40, copolymerization of styrene with TREM LF-40, and the influence of the homopolymer of TREM LF-40 [poly(TREM)] and/or the copolymer [poly(TREM-co-styrene)] on the entry and exit rates of free radicals. The possibility of both chain transfer and copolymerization exists primarily at the oil/water interface, whereas both can also occur in the aqueous and monomer phases. Bulk polymerizations of styrene in the presence of TREM LF-40 and poly(TREM) were conducted, and the results show that the reaction rate decreased for the styrene/TREM LF-40 system. Latex characterization by serum replacement and titration measurements provided evidence for the chemical bonding of TREM LF-40 to the polymer particles. The fraction of chemically bound reactive surfactant decreased with increasing surfactant concentration and increased with increasing initiator concentration. Relatively high contact angles of water on films cast from the latexes showed that TREM LF-40 did not migrate significantly to the surface of the film, which was consistent with the latex-surface characterization results. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3093–3105, 2001
Investing in International Real Estate Stocks: A Review of the Literature

This paper summarises the various findings of studies completed on the benefits of international diversification using real estate stocks. With the increased availability of data and analytical tools, the quantity and variety of work over the past decade have increased dramatically in this area. The first two sections of the paper chronologically review the studies, focusing on how the diversification benefits are analysed: in a mixed-asset portfolio context or a real-estate-only portfolio context. The third section highlights work that uses alternative analyses to the traditional mean-variance framework to examine the international real estate stock as an investment alternative. Almost all of the studies reach the same conclusion: diversification gains are possible but are often reduced if currency risk is included in the analysis.
On reduction of block matrices in a Hilbert space

We study the problem of the reduction of self-adjoint block matrices B = (B ij ) with given graph by a group of unitary block diagonal matrices. Under the condition that the matrices B 2 and B 4 are orthoscalar, we describe the graphs of block matrices for which this problem is a problem of *-finite, *-tame, or *-wild representation type.
Contralateral cochlear implantation prior to vestibular nerve section for 'drop attacks' in the only hearing ear.

Background: A dilemma occurs in the treatment of second-sided Meniere's disease in the only hearing ear, particularly in patients with severe symptoms such as ‘drop attacks’. This paper describes a patient treated with contralateral cochlear implantation prior to vestibular nerve section of the symptomatic ear. Case report: A 53-year-old man, with second-sided Meniere's disease and drop attacks in the only serviceable right ear, underwent successful left cochlear implantation 30 years after hearing loss, followed by right vestibular nerve section. The patient achieved control of Meniere's attacks and improved hearing. Although the patient experienced oscillopsia post-operatively, he was satisfied with his improved everyday functioning. Conclusion: Patients with severe second-sided Meniere's disease in the only hearing ear are a small but difficult treatment group. In those that are suitable for cochlear implantation in the non-serviceable ear, it is suggested that this be employed prior to surgical treatment of the Meniere's symptoms, even if the implanted ear has had no auditory stimulation for many years.
A performance comparison between new reduced surface drain "RSD" LDMOS and RESURF and conventional planar power devices rated at 20 V

This work presents a new reduced-surface-drain (RSD) type of LDMOS in comparison with very thin RESURF (VTR) and conventional (CONV) devices for 20 V BiCMOS market applications. Competitive performance results obtained for the RSD, VTR and CONV devices are respectively R/sub sp/=0.39 m/spl Omega//spl middot/cm/sup 2/ BV=24.4 V; R/sub sp/=0.30 mn/spl Omega//spl middot/cm/sup 2/, BV=25 V; R/sub sp/=0.59 m/spl Omega//spl middot/cm/sup 2/, BV=18-20 V. All R/sub sp/, measurements are with 3 MV/cm gate stress(V/sub gs/=12.75 V, Tox=425 /spl Aring/).
Reciprocal Ferrite Devices in TEM Mode Transmission Lines

Several new reciprocal ferrite devices have been designed in TEM mode transmission lines to operate over both narrow and extremely broad bandwidths in the low-microwave frequency region. These include variable attenuators, an amplitude modulator, and a traveling-wave tube equalizer. Each component utilizes the attenuation associated with gyromagnetic resonance in low saturation magnetization ferrites. The techniques used to overcome the matching problems inherent in TEM mode transmission lines when ferrite loaded, and the design considerations pertinent to each component, are treated in detail. The parameters affecting the characteristics of each device are discussed and both final design and operating characteristics of the components are presented.
The management of the shoulder prosthesis infection

Infection following total shoulder arthroplasty, although uncommon, can be a devastating complication. The established incidence ranges from 0% to 3.9% [1]. Patients commonly present with pain; many show radiographic evidence of loosening. Unlike management of total knee and hip arthroplasty, management of these infections has limited description in the literature. Treatment options include: suppressive antibiotics, combined joint debridement and antibiotic therapy, resection arthroplasty, primary exchange arthroplasty, and two-stage reimplantation [4].
Observations on the status and distribution of the West African manatee in Cameroon

Summary During June-August 1989, a survey of manatee distribution and status in Cameroon was undertaken by conducting land and boat surveys of four regions: Korup, Mamfe, Edea, and Kribi. Manatee density, based on frequency of reported sightings, appears to be high in certain areas of Korup, Mamfe, and Edea. Manatee exploitation does not appear to be common. The reasons for this, however, are due to human attitudes and perceptions towards the manatee rather than laws protecting the manatee. This study underscores the importance of understanding human attitudes associated with a particular species if we are to develop effective conservation strategies for species survival. Resume De juin a aout 1989, on a mene une etude sur la distribution et le statut des lamantins au Cameroun, en parcourant sur terre et par bateau quatre regions: Korup, Mamfe, Edea et Kribi. La densite des lamantins, basee sur la frequence des observations rapportees, semble elevee dans certaines regions de Korup, Mamfe et Edea. L'exploitation des lamantins ne semble pas etre commune. Les raisons en sont cependant dues a l'attitude et a la fa¸on des hommes de voir les lamantins plutot qu'a des lois qui les protegeraient. Cette etude souliqne l'importance d'une bonne comprehension de l'attitude des hommes vis-a-vis d'une espece particuliere si nous souhaitons mettre au point une strategie de conservation efficace pour la survie de l'espece.
Deconvolution using orthogonal polynomials in nuclear medicine: a method for forming quantitative functional images from kinetic studies

A deconvolution technique is described which utilizes orthogonal polynomials (DOP) and handles inevitable noise in such a way that pixel time activity curves can be deconvolved. This solves the issue of quantitative analysis of serial scintigraphic data in a manner that preserves the high spatial resolution inherent in raw data. In the current work a complete mathematical description of the new deconvolution technique is presented. The DOP method is designed for use with an array processor and results in a set of linear response function (LRF) images. Techniques to calibrate the measuring devices and correct for distorted input functions in order to obtain the LRF images in absolute units are described. A simulation study compares the DOP method with the Fourier transform and the discrete deconvolution algorithm both with and without various noise levels. The impact on the convergence of the DOP algorithm of undesired blood activity simultaneously measured with the organ-target activity was simulated. >
Hepatic vascular shunts: embryology and imaging appearances

The purpose of this pictorial review is to understand the embryological basis of the development of congenital hepatic vascular shunts and to review the multimodality imaging appearances of congenital and acquired hepatic vascular shunts. Hepatic vascular shunts are commonly seen in imaging. Familiarity with their characteristic appearances is important in order to accurately characterise these shunts and diagnose the underlying disorders.
Proinflammatory cytokine responses to P. aeruginosa infection in human airway epithelial cell lines.

A tendency toward excessive inflammation in cystic fibrosis (CF) patients often accompanies lung infections with Pseudomonas aeruginosa. We tested the cytokine response to P. aeruginosa in two pair...
Reduced Frequencies and Heightened CD103 Expression among Virus-Induced CD8+ T Cells in the Respiratory Tract Airways of Vitamin A-Deficient Mice

Vitamin A deficiency (VAD) has profound effects on immune responses in the gut, but its effect on other mucosal responses is less well understood. Sendai virus (SeV) is a candidate human parainfluenza virus type 1 (hPIV-1) vaccine and a candidate vaccine vector for other respiratory viruses. A single intranasal dose of SeV elicits a protective immune response against hPIV-1 within days after vaccination. To define the effect of VAD on acute responses toward SeV, we monitored both antibodies and CD8(+) T cells in mice. On day 10 following SeV infection, there was a trend toward lower antibody activities in the nasal washes of VAD mice than in those of controls, while bronchoalveolar lavage (BAL) fluid and serum antibodies were not reduced. In contrast, there was a dramatic reduction of immunodominant CD8(+) T cell frequencies in the lower respiratory tract (LRT) airways of VAD animals. These T cells also showed unusually high CD103 (the αE subunit of αEβ7) expression patterns. In both VAD and control mice, E-cadherin (the ligand for αEβ7) was better expressed among epithelial cells lining the upper respiratory tract (URT) than in LRT airways. The results support a working hypothesis that the high CD103 expression among T cell populations in VAD mice alters mechanisms of T cell cross talk with URT and LRT epithelial cells, thereby inhibiting T cell migration and egress into the lower airway. Our data emphasize that the consequences of VAD are not limited to gut-resident cells and characterize VAD influences on an immune response to a respiratory virus vaccine.
The use of barium salts of protected deoxyribonudeoside-3′ p-chlorophenyl phosphates for construction of oligonucleotides by the phosphotriester method: high-yield synthesis of dinucleotide blocks

Abstract A new experimental approach to the synthesis of polydeoxyribonucleotides via the phosphotriester method involves construction of oligonucleotide blocks by direct use of the easily prepared barium salts of O5',N-protected deoxyribonucleoside-3' p-chlorophenyl phosphates as the key monomers in condensation reactions. The procedure has been demonstrated by the rapid synthesis in high yield and purity of all sixteen fuly protected dinucleotides (Formula: see text) (where dN' = dT, dbzC, dbzA, or dibG; (Formula: see text) This set of molecules constitutes a "syllabary" for the preparation of defined sequence oligonucleotides.
Enhanced Cytotoxicity of RIPTK Gene Therapy of Pancreatic Cancer via PDX-1 Co-Delivery

Background Using in vivo mouse models, we have demonstrated that the insulin promoter-driven suicidal gene therapy (RIPTK) could be used in the treatment of mouse insulinoma and human pancreatic cancer cells. However, limitations of this therapy include tumor cells lack of sufficient PDX-1 protein and low levels of transgene expression mediated by liposome delivery system. The purpose of this study was to determine 1) whether transient transfection of PDX-1 into selected pancreatic cancer cells would lead to increased RIPTK cytotoxicity, and 2) whether an adenoviral delivery system would increase the overall RIPTK gene expression in vitro . Material and methods RIPlacZ and RSVlacZ plasmid DNA as well as AdCMVlacZ and AdRIPlacZ were used in transfection assays in human pancreatic cancer cell lines PANC-1 and MIA PaCa2 ( n = 8). An expression plasmid DNA containing the mouse PDX-1 cDNA was also used. LacZ reporter assays were performed. RIPTK genes constructed either in plasmid or in adenoviral vectors were used in cytotoxic assays. RT-PCR assays were used to determine PDX-1 expression levels. Results PDX-1 protein was detected in the human pancreatic ductal carcinoma cell line PANC-1, a little in MIA PaCa2 cells. Liposome mediated (L) RSVlacZ and RIPlacZ transfection in PANC-1 cells resulted in 10.1% and 9.3% transgene expression, respectively. Co-delivery of PDX-1 had no significant effect on RSVlacZ expression (9.3%, P = NS) but significantly increased RIPlacZ gene expression (14.9% P P P P P = NS). MIA PaCa2 cells treated with RIPTK alone resulted in 4.9% cell death and increased to 18.2% when exogenous PDX-1 was co-delivered ( P P Conclusions These data demonstrated that adenoviral mediated gene delivery resulted in a significant increase of transgene expression compared with liposomal delivery systems. RIPTK mediated cytotoxicity was also significantly enhanced via co-delivery of exogenous PDX-1 in these cells. Thus, these results also indicated that PDX-1 plays critical roles in insulin promoter activation and demonstrated that PDX-1 production is essential for insulin promoter-directed gene therapy.
Cross Pressures of Accountability: Initiative, Command, and Failure in the Ron Brown Plane Crash

Contemporary political rhetoric and management reforms have highlighted accountability issues for government. A troubling feature associated with these management reforms is a gap between the expectations of management reform and the reality of the American culture of accountability. This culture gap is likely to be particularly evident in organizations that are structured around principles of command and control, such as the military. This article explores the cross pressures individuals face when they are urged to demonstrate initiative and obedience to command while operating within a web of accountability relationships that represent several different behavioral standards against which their performance can be judged. To conduct this research, the authors interviewed members of the Accident Investigation Board appointed by Major General Ryan, Commander of the United States Air Force Europe (USAFE), to investigate the April 1996 crash in Croatia of the military transport plane carrying United States Secretary of Commerce Ron Brown and his party of distinguished visitors. These personal interviews were supplemented with the official reports of the Accident Investigation Board and transcripts of testimony before the Board. Based on these data, we analyze the accountability dynamics involving the various military officials associated with the “mishap flight.” We find that while institutional rhetoric and managerial conditions encouraged entrepreneurial behavior and initiative, the administrative reality still emphasized a risk-averse, rules-oriented approach to accountability when things went wrong.
New ligands for melanocortin receptors.

Named originally for their effects on peripheral end organs, the melanocortin system controls a diverse set of physiological processes through a series of five G-protein-coupled receptors and several sets of small peptide ligands. The central melanocortin system plays an essential role in homeostatic regulation of body weight, in which two alternative ligands, α-melanocyte-stimulating hormone and agouti-related protein, stimulate and inhibit receptor signaling in several key brain regions that ultimately affect food intake and energy expenditure. Much of what we know about the relationship between central melanocortin signaling and body weight regulation stems from genetic studies. Comparative genomic studies indicate that melanocortin receptors used for controlling pigmentation and body weight regulation existed more than 500 million years ago in primitive vertebrates, but that fine-grained control of melanocortin receptors through neuropeptides and endogenous antagonists developed more recently. Recent studies based on dog coat-color genetics revealed a new class of melanocortin ligands, the β-defensins, which reveal the potential for cross talk between the melanocortin and the immune systems.
An electronically reconfigurable reverberation chamber for the emulation of severe multipath channels

This paper covers the design of a new bench-top environment for testing wireless systems under severe multipath conditions. Reverberation chambers, upon which this design is based, have used a moving ‖stirring blade‗ to create multiple multipath channels. In this work, a set of electronically-controlled interference antennas is also used to develop multipath scenarios including newly demonstrated hyper-Rayleigh conditions. In addition, the work discusses correlations between severe fading and S 21 group delay.
Reform and Gifted Black Students: Promising Practices in Kentucky

Gifted education has had altogether too little voice in the educational reform discourse. All too often, educators and policymakers who do not work directly with the gifted assume that gifted learners require no special attention to their needs. Despite considerable evidence that such problems as underachievement, lack of achievement motivation, and dropping out of school occur often and even disproportionately among the gifted, educators and policymakers rarely address the needs of gifted students directly in the reform reports, particularly those of the 1980s. More recently, however, reform movements at the state level have adopted components that appear, albeit indirectly, to address the needs of gifted learners. Accordingly, this article highlights some of the promising components of educational reform currently underway in the Commonwealth of Kentucky and discusses their implication for gifted students in general, and gifted Black students in particular.