cssi/SciSciGPT-SciSciNet huggingface dataset:
On the circuit depth of structurally reversible cellular automata

We study the family of structurally reversible cellular automata that use the (generalized) Margolus neighborhoods. We show that every reversible cellular automaton (RCA) can be embedded into the standard two layer Margolus neighborhood defined by two overlapping square partitions of the cellular space and two one-to-one local rules. The embedding allows step-by-step simulations. Then we investigate how many layers of one-to-one local rules are required in exact representations of RCA. We show how in the d-dimensional cellular space any consecutive d + 2 layers can be combined into d + 1 layers. This proves that no more than d + 1 layers are necessary. We demonstrate that in the two-dimensional case d = 2 the number d + 1 is optimal by providing an example of an RCA with three layers of local rules that cannot be expressed in two layers.
Absenteeism and Exam Performance: Evidence for Introductory Microeconomics

The effect of absenteeism on students’ exam performance during an introductory microeconomics course was examined. The focus was on the impact of absenteeism in the prior exam period on current exam performance. Results showed a negative and significant correlation – one additional class missed was found to lower test scores by approximately 2-3 points and reduce exam performance by approximately 3-6%. One additional class missed in the first and second exam periods was found to lower final exam scores by approximately 4 and 2 points, and reduce final exam performance by approximately 6.5% and 3.4%, respectively. Moreover, the cumulative absenteeism effect was found to be significant on final comprehensive exam performance while not significant on second midterm exam performance. In addition, the post-exam effect was tested and found not to be significant. An implied issue was discussed – attendance be compulsory? Findings suggest that an incentive-stimulating attendance strategy may be considered as a substitute for a mandatory attendance policy.
MODES AND MEASURES OF CYCLIC COMBUSTION VARIABILITY

A single-cylinder engine with a transparent piston crown was tested with three intake geometries which produced different levels of swirl, and with two spark locations. A heat-release analysis was performed on the accumulated pressure-time data. Using this data base, relationships of maximum cycle pressure and its location in the cycle to the placement of the burn in the cycle are developed for different burning rates as a means of diagnosing sources of combustion variability. Among the significant observations were that combustion variability for operation away from the lean limit or incipient misfire is not strongly dependent on flow conditions at the spark plug and early flame behavior, but more dependent on the cyclic repeatability of the overall cylinder flow pattern. In the region of incipient misfire the early flame process becomes a significant source for variability. The onset of significant variability in IMEP corresponds to a condition where a collection of cycles shows the production of an increasing number of abnormally late burns as the spark is advanced. Additional spark advance results in the occurrence of misfire at approximately the frequency of the late-burn occurrence.
Isolation and Structural Identification of a New Metabolite of Fusarium equiseti.

A fluorescent compound was isolated and purified from rice cultures of Fusarium equiseti (Alaska 2-2). Mass spectrometry and nuclear magnetic resonance data indicated that its structure is 2,2-dimethyl-5-amino-6-(3′-hydroxyl-4′-methoxyl-butyryl)-4-chromone. It is an analog of the mycotoxin fusarochromanone, in which the amino group on C-3′ is replaced by a hydroxyl group and the hydroxyl group on C-4′ is replaced by a methoxyl group.
Tekeni-Two Worlds, Many Borders: A Look at Classical Native Music through Indigenous Eyes

Dans cet article, j'aborde diverses oeuvres creees par des compositeurs classiques amerindiens qui invitent a repenser les dichotomies entre classique et traditionnel, oral et ecrit, amerindien et europeen, autochtone et colonial, et qui permettent de contribuer aux discussions en cours sur la facon dont la recherche universitaire peut refleter les savoirs autochotones tout en incorporant des theories et des choix stylistiques utilises par certains ethnomusicologues modernes afin de retablir et de refleter le point de vue autochtone. Partant du concept de gemellite emprunte au recit de la creation mohawk ainsi que des travaux sur la complementarite et la dualite menes par les ethnomusicologues Diamond, Cronk, von Rosen et Browner, j’elargis cette metaphore a l’aide des contributions des Deloria, de Little Bear, Smith et Wilson afin d’examiner comment negocier les frontieres entre la recherche autochtone et empirique, entre les theories anciennes et nouvelles, et entre les concepts classiques et autochtones tels qu’ils sont reveles dans les oeuvres elles-memes.Cet article utilise la recherche de terrain, l’analyse et les questionnaires pour aborder la question des frontieres musicales refletees dans la musique contemporaine ameriendienne, en etudiant les oeuvres et des idees des compositeurs Chacon (Navajo Dine), Archambault (Kichespirini), Nakai (Navajo/Ute), Davids (Mohican) et Quincy (Choctaw). De surcroit, je porte un regard reflexif sur mes propres compositions et mes interpretations musicales en tant qu’ethnomusicologue, interprete et une compositrice d’ascendance mohawk.
Studies on porcine costal cartillage protein-polysaccharide complex. I. Enzymatic degradation.

Abstract Enzymatic degradation of porcine costal cartillage protein-polysaccharide complex with papain (EC 3.4.4.10) followed by fractionation on Sephadex and Sephadex ion-exchange columns yields two distinct polysaccharide fractions, designated A and B. The former, major fraction, still contains covalently-bound peptide and the majority of the glucosamine content of the parent polysaccharide. Hydrazinolysis experiments suggest that serine is the predominant, if not exclusive, residue to which the polysaccharide chains of this fraction are attached. The second polysaccharide fraction contains essentially no glucosamine, little or no polypeptide, and may be linked to the peptide in a different manner from the first fraction. Alkali elimination of polysaccharide from Fraction A followed by high-voltage electrophoresis yields several peptides; the partial structure of one of these was determined as Glu-Gly-dehydroAla-Gly. It is not possible to reconstruct the entire complex but this relatively unhindered linkage may be common for substitution of reactive serines with polysaccharide chains. Both xylose and galactose were identified in Fraction A by gas-liquid chromatography.
Studies on platelets

Abstract 1.1. A attempt was made to induce platelet antibody production in rabbits by injection of antigenically modified platelets. Modification of platelets was attempted by: (a) washing and standing; (b) incubation with drugs (aminopyrine, quinine, quinidine); (c) treatment with bacterial filtrates (Streptococcus hemolyticus and Staphylococcus albus and aureus); (d) treatment with Newcastle disease virus. Treated platelets were injected into 3 groups of rabbits; one received human platelets (heterologous immunization), one received platelets from normal rabbits (isoimmunization), and the third group received their own platelets (autoimmunization). Development and specificity of platelet agglutinins were evaluated by standard immunologic methods in vivo and in vitro. 2.2. High titer heteroimmune agglutinins developed constantly against human platelets. There was not, however, evidence for a specific antigenicity of modified versus nonmodified platelets. In one animal a naturally occurring isoantibody decreased in titer as the heteroantibody developed. 3.3. Autoantibodies and isoantibodies were often detected in the serum of rabbits receiving their own modified platelets in the presence or in the absence of the modifying agent. Animals receiving isoimmunization failed, however, to develop specific antibodies in vitro. Changes in protein and glycoprotein electrophoretic pattern were noted in the serum of auto- and isoimmunized rabbits, which were similar to those obtained in other instances of experimental immunization. When the specific modifying agent was injected into auto- or isoimmnnized rabbits, significant thrombocytopenia followed in many instances. The state of immunization was short-lived (less than 3 months). Results of our experiments indicated the simultaneous development of isoimiminization and autoimmunization in the course of the injection of modified auto- or isoplatelets. 4.4. Experimental results were not constant and reproducible in all animals of any given group. This is quite in agreement with the observations in humans, where only a few individuals, among many, develop thrombocytopenia after exposure to drugs, bacteria, and viruses. 5.5. Some of the findings obtained in the course of these studies could be applied to the interpretation of the pathogenesis of some thrombocytopenic states in man.
New Insights on Geomagnetic Storms from Model Simulations Using Multi-Spacecraft Data

The forecast of the terrestrial ring current as a major contributor to the stormtime Dst index and a predictor of geomagnetic storms is of central interest to ‘space weather’ programs. We thus discuss the dynamical coupling of the solar wind to the Earth's magnetosphere during several geomagnetic storms using our ring current-atmosphere interactions model and coordinated space-borne data sets. Our model calculates the temporal and spatial evolution of H+, O+, and He+ ion distribution functions considering time-dependent inflow from the magnetotail, adiabatic drifts, and outflow from the dayside magnetopause. Losses due to charge exchange, Coulomb collisions, and scattering by EMIC waves are included as well. As initial and boundary conditions we use complementary data sets from spacecraft located at key regions in the inner magnetosphere, Polar and the geosynchronous LANL satellites. We present recent model simulations of the stormtime ring current energization due to the enhanced large-scale convection electric field, which show the transition from an asymmetric to a symmetric ring current during the storm and challenge the standard theories of (a) substorm-driven, and (b) symmetric ring current. Near minimum Dst there is a factor of ∼ 10 variation in the intensity of the dominant ring current ion specie with magnetic local time, its energy density reaching maximum in the premidnight to postmidnight region. We find that the O+ content of the ring current increases after interplanetary shocks and reaches largest values near Dst minimum; ∼ 60% of the total ring current energy was carried by O+ during the main phase of the 15 July 2000 storm. The effects of magnetospheric convection and losses due to collisions and wave-particle interactions on the global ring current energy balance are calculated during different storm phases and intercompared.
Book reivew: Qualitative Motion Understanding by Wilhelm Burger and Bit Bhanu (Kluwer Academic Publishers 1992)

This book is a summary of a research project sponsored by the Advanced Research Projects Agency (ARPA) in service of one of its great challenges: creating an autonomous land vehicle (ALV). This book reports on the computer vision problems associated with having an ALV interpret the scene as it moves through its environment. The main problems addressed by this work are to separate the moving objects from the stationary objects in the scene (as the ALV moves) and to detect how the moving objects are moving with respect to the ALV.
Regulating in the Shadows: Systemic Moral Hazard and the Problem of the Twenty-First Century Bank Run

An important, emerging literature suggests that the proximate cause of the recent financial crisis was an old-fashioned bank run of the sort that was common prior to the Great Depression. But instead of individuals converging on the local savings and loan, this bank run involved investment banks’ short-term creditors who began withdrawing their cash from these banks out of concern for the quality of the underlying collateral, which consisted largely of complex asset-backed securities. A growing chorus of commentators has suggested that we should treat this run on “securitized banking” in the same way that we treated its Depression-era counterpart, including through a form of deposit insurance. In this Article, I question the reliability of this analogy by focusing on what I refer to as the “systemic moral hazard” problem posed by a deposit insurance regime for securitized banking. This problem arises because insuring short-term creditors in this context is likely to introduce moral hazard (or increased risk-taking as the result of insurance) not only at the bank but also in the “securitization process” itself, which is the process for manufacturing the securities that these banks rely on as collateral for their short-term borrowing. Because other investors purchase these securities and may ignore or neglect their risks, the moral hazard problem of deposit insurance in this context is potentially more costly than in the traditional banking context. This analysis gives rise to two implications. First, the systemic moral hazard problem suggests that the scope of the regulated entity under a deposit insurance regime for securitized banking would need to be much broader than the definition adopted by current banking law, which focuses regulatory oversight on the deposit-taking institution alone. However, the more expansive regulatory task implicit in this broader definition would test regulatory competence to a greater degree than in traditional banking. Consequently, the second implication of my analysis is that the systemic moral hazard problem suggests a need to consider potential policy alternatives for dealing with the twenty-first century bank run. I briefly consider three such alternatives, which focus on eliminating, limiting or circumscribing the securitized bank’s reliance on short-term debt to finance its purchase of long-term asset-backed securities.
Trapping Channel Block of NMDA-Activated Responses By Amantadine and Memantine

Blanpied, Thomas A., Faye Boeckman, Elias Aizenman, and Jon W. Johnson. Trapping channel block of NMDA-activated responses by amantadine and memantine. J. Neurophysiol. 77: 309–323, 1997. We invest...
Sound, Rhythm and Structure: John Cage's Compositional Process Before Chance

Abstract Although chance, or the removal of personal influence from the compositional method, did not play a part in John Cage's work until 1951 when he began to use the / Ching to make artistic decisions, techniques used during the 1930s anticipate those associated with chance operations. In this study, analyses of the following works will illustrate how these techniques point to his eventual use of chance: Solo with Obbligato Accompaniment of Two Voices in Canon, and Six Short Inventions on the Subjects of the Solo (1933–34); Quartet for percussion (1935); and Imaginary Landscape No. 1(1939).
Observation of coherent optical coupling within inorganic-organic hybrid nanoparticles

We report on the study of the optical properties of hybrid systems made from molecular aggregates (J-aggregates) and metallic nanoparticles (Au and Ag). Both entities have outstanding optical properties that have been extensively addressed both through experimental and theoretical efforts. The J-aggregates were chosen for their linear and non-linear excitonic response that shows among other intriguing properties, superradiant emission, ultrafast optical switching, and electroluminescence. These J-aggregates form spontaneously on the surface of Au and Ag nanoparticles, used primarily to excite the organic shell through optical near-field interaction. Steady state as well as ultrafast spectroscopic measurements was used to characterize the nature of the interaction between the two constituents as well as to follow the dynamics of the exciton in the aggregate upon near-field excitation from the particle. For both Au and Ag, Mie scattering theory calculations of the hybrid ground state absorption spectra account for the experimental observations and reflect the coherent coupling between the excitonic states in the aggregate and the nanoparticles electronic transition dipoles. Furthermore we show that the dipole-dipole coupling strength between the individual molecules in the aggregate is increased by ~30% on the surface of the particle compared to its value in solution. The different dynamics of these nanosystems have been probed using femtosecond spectroscopy and reveals contrasted relaxation pathways for the exciton when interacting with Ag with respect to Au as well as a delay dependent excitonic coherent length.
Announcement, Credibility, and Turnout in Popular Rebellions

The dynamics of popular rebellions against authoritarian governments are examined by focusing on how the public's beliefs about the durability of an authoritarian government may have a self-fulfilling quality. This self-fulfilling quality gives both government and opposition leaders an incentive to make exaggerated “announcements” about the likelihood of a rebellion in the near future. Yet if their predictions are too far off, they will lose credibility, and their future announcements will carry less weight. The case of Indonesia, where the government's loss of credibility and the opposition's ability to exploit this weakness led to a popular uprising in 1998, is examined. A computational model consisting of a government, an opposition, and a population of citizens with heterogeneous preferences is developed to explore how announcements by the opposition and the government can influence the likelihood of rebellion. Results suggest that when the government's credibility is high, the opposition can do littl...
Global nonlinear compression of natural luminances in painted art

Over the past quarter century, measures of statistical regularities of natural scenes have emerged as important tools in explaining the coding properties of the mammalian visual system. Such measures have recently been extended to the study of art. Our own work has shown that a log nonlinearity is a reasonable first approximation of the type of luminance compression that artists perform when they create images. But how does this nonlinearity compare to those that artists actually use? In this paper, we propose a model of the global luminance compression strategy used by one artist. We also compare the curves required to transform natural scenes so that the scene luminance histograms matched the histograms of a number of collections of art, and we tested the response of observers to those scenes. The collections included a group of Hudson River School paintings; a group of works deemed to be "abstract" works in a forced-choice paradigm; collections of paintings from the Eastern and Western hemispheres; and other classes. If a single transform were sufficient to compress images in the way artists do, we would expect these transforms all to be log-like and on average, there should be little or no difference in observer preference for the collection of natural scenes when they are compressed according to these transforms. We find instead that these groupings of art have distinct transforms and that Western observers prefer many of these transforms over a log transform. Together these findings offer evidence that a painter's global luminance compression strategy-or "artist's look-up table"-may be a fundamental property of a given painter or grouping of paintings, though further study is needed to establish what factors determine the shape of this transform. We discuss a number of possible factors.
Hydrogen bonding between acetone and silica gel, as studied by NMR

13C NMR spectra and relaxation parameters (T1H, T1C, T1ρH, TCH) were measured via CP-MAS and DP-MAS techniques as a function of acetone loading level in acetone/SiO2 samples at 25 °C. T1H and T1ρH values were also measured via 29Si CP-MAS experiments. Peak positions and relaxation parameters are averaged by rapid exchange between different acetone interaction sites on the surface. The data were analyzed in terms of a surface equilibrium of adsorbed acetone units between hydrogen-bonding and non-hydrogen-bonding sites. Data analysis by this model yielded the surface concentration of hydrogen-bonding (silanol) sites (1.5 nm-2) and the equilibrium constant (K = 3.0 nm2). Variable-temperature experiments (124−297 K) at three loading levels yielded values of ΔH° (−5.8 ± 0.3 kJ mol-1) and ΔS° (−12.5 ± 0.7 J K-1 mol-1). A self-consistent, qualitative interpretation of measured relaxation parameters is made in terms of the relative mobilities of hydrogen-bonded (less mobile) and non-hydrogen-bonded (more mobile) ...
Mental disorders in cancer patients: a study of 100 psychiatric referrals.

Records of 100 consecutive hospitalized cancer patients referred for psychiatric consultation were reviewed. These patients constituted only 5% of those seen by the Psychiatry Consultation Service during the study period. Fifty-six percent of the referred patients were diagnosed as depressed and 40% as having organic brain disease. Twenty-six of the 100 patients were misdiagnosed by the referring physician as depressed but were classified by the staff psychiatrist as suffering from organic brain syndrome. When referral was studied by primary site of cancer, only patients with breast cancer were referred at a significantly higher than expected rate (p less than .001). The importance of the mental status examination as a routine procedure in all cancer patients is stressed so that an organic brain syndrome will not be missed. Suggestions for patient management are given.
MDC1 Maintains Genomic Stability by Participating in the Amplification of ATM-Dependent DNA Damage Signals

Summary MDC1 functions in checkpoint activation and DNA repair following DNA damage. To address the physiological role of MDC1, we disrupted the MDC1 gene in mice. MDC1 −/− mice recapitulated many phenotypes of H2AX −/− mice, including growth retardation, male infertility, immune defects, chromosome instability, DNA repair defects, and radiation sensitivity. At the molecular level, H2AX, MDC1, and ATM form a positive feedback loop, with MDC1 directly mediating the interaction between H2AX and ATM. MDC1 binds phosphorylated H2AX through its BRCT domain and ATM through its FHA domain. Through these interactions, MDC1 accumulates activated ATM flanking the sites of DNA damage, facilitating further ATM-dependent phosphorylation of H2AX and the amplification of DNA damage signals. In the absence of MDC1, many downstream ATM signaling events are defective. These results suggest that MDC1, as a signal amplifier of the ATM pathway, is vital in controlling proper DNA damage response and maintaining genomic stability.
HLA-Specific Antibodies are Risk Factors for Lymphocytic Bronchiolitis and Chronic Lung Allograft Dysfunction

Bronchiolitis obliterans syndrome (BOS) represents a major limitation in lung transplantation. While acute rejection is widely considered the most important risk factor for BOS, the impact of HLA-specific antibodies is less understood. Of 51 lung recipients who were prospectively tested during a 4.2 +/- 1.6-year period, 14 patients developed HLA-specific antibodies. A multi-factorial analysis was performed to correlate the prevalence of BOS with HLA antibodies, persistent-recurrent acute rejection (ACR-PR), lymphocytic bronchiolitis, and HLA-A, -B, and -DR mismatches. HLA-specific antibodies were associated with ACR-PR (10/14 vs. 11/37 with no antibodies, p < 0.05), lymphocytic bronchiolitis (8/14 vs. 10/37, p < 0.05), and BOS (10/14, vs. 9/37, p < 0.005). Other risk factors for BOS were: lymphocytic bronchiolitis (13/18 vs. 6/33 with no lymphocytic bronchiolitis, p < 0.0001), ACR-PR (12/21 vs. 7/30 with no ACR-PR, p < 0.05), and the number of HLA-DR mismatches (1.7 +/- 0.48 in BOS vs. 1.2 +/- 0.63 without BOS, p < 0.05). The presence of antibodies exhibited a cumulative effect on BOS when it was associated with either lymphocytic bronchiolitis or ACR-PR. The complex relationship between the development of HLA antibodies and acute and chronic lung allograft rejection determines the importance of post-transplant screening for HLA-specific antibodies as a prognostic element for lung allograft outcome.
FKBP12 Binds the Inositol 1,4,5-Trisphosphate Receptor at Leucine-Proline (1400–1401) and Anchors Calcineurin to this FK506-like Domain

The immunophilin FKBP12 is one of the most abundant and conserved proteins in biology. It is the primary receptor for the immunosuppressant actions of the drug FK506 in whose presence FKBP12 binds to and inhibits calcineurin, disrupting interleukin formation in lymphocytes. The physiologic functions of FKBP12 are less clear, although the protein has been demonstrated to physiologically interact with the inositol 1,4,5-trisphosphate receptor (IP3R), the ryanodine receptor, and the type 1 transforming growth factor β receptor. We now report that FKBP12 binds the IP3R at residues 1400–1401, a leucyl-prolyl dipeptide epitope that structurally resembles FK506. We further demonstrate that binding to IP3R at this site enables FKBP12 to interact with calcineurin, presumably to anchor the phosphatase to IP3R and modulate the receptor's phosphorylation status. We propose that FK506 promotes an FKBP12-calcineurin interaction by mimicking structurally similar dipeptide epitopes present within proteins that use FKBP12 to anchor calcineurin to the appropriate physiologic substrates.
Reproductive Cancer Risk Factors among Alaska Native Women: The Alaska Education and Research Towards Health (EARTH) Study

Abstract Background The purpose of this study was to provide estimates for the prevalence of reproductive cancer risk factors among Alaska Native (AN) women who enrolled in the Alaska Education and Research Towards Health (EARTH) Study from 2004 to 2006. Methods A total of 2,315 AN women 18 years or older completed reproductive health questions as part of a comprehensive health history questionnaire. The reproductive health section included menstrual status (age at menarche and menopause), pregnancy and live birth history, use of hormonal contraception, hormone replacement therapy, and history of hysterectomy and/or oophorectomy. Results A total of 463 (20%) of women experienced menarche before age 12 with a decline in mean age at menarche by age cohort. More than 86% had been pregnant (mean number of pregnancies, 3.8; mean number of live births, 2.9). More than one half of women (58%) had their first live birth between the ages of 18 and 24. Almost 28% of participants had completed menopause, of whom 24% completed menopause after age 52. Fewer than half (43%) reported ever using hormone replacement therapy. Almost two thirds (62%) reported ever using oral contraceptives, and fewer reported ever using birth control shots (30%) or implants (10%). Conclusions This study is unique in reporting reproductive health factors among a large group of AN women. These data show that AN women have selective protective factors for reproductive cancers, including low nulliparity rates, low use of menopausal estrogens, and common use of contraceptive hormones. However, analysis by age cohorts indicates decreasing age at menarche that might increase the risk for reproductive cancers among AN women in the future.
Effect of minor doping on the high current application of the ZnO varistor

Abstract The ZnO varistor is a multiphase polycrystalline ceramic which is comprised of an array of nearly conductive grains separated by nearly insulating grain boundaries. This gives rise to a current-voltage characteristic which is ohmic at low current densities, non-ohmic at intermediate current densities and again ohmic at higher current densities. Depending on applications, there is often a need to maximize or minimize these characteristics. For protecting electrical equipment from lightning surges, for example, there is a need to increase the high current nonlinear coefficient to enhance the protective characteristic of the device. This paper illustrates how this protective characteristic can be enhanced by minor doping with a trivalent ion such as Al3+. The results confirm previous studies which show that Al3+ acts as a donor in small concentrations and as an acceptor in large concentrations.
Superconductors in BiO-CuO-(Sr0.5, Ca0.5)O system

Aurivillius oxides having mole ratio of BiO(Sr0.5, Ca0.5) = 12 are not only good conductors at room temperature but also superconductors having a Tc range from 83 to 107 K. The superconducting compositions in this system are accompanied by large expansion during sintering. An oxide BiSrCaCu2Ox (n = 2) shows a maximum Tc value, 107 K, and an onset temperature well above the Tc.
Magnetic configurations of hybrid ferromagnetic dot-superconductor systems

Abstract In-plane single domain and vortex magnetization configurations of the magnetic dot in the hybrid superconductor–ferromagnet system are considered. Single domain configuration energy shift due to the presence of superconductor is calculated. The change of the phase curve of the ferromagnetic dot magnetization due to the repulsion of the magnetic field by the superconductor is obtained. Up to the two-fold decrease of the ferromagnetic dot critical radius due to the presence of the superconductor is predicted.
Therapeutic efficacy of laparoscopic cholecystectomy in the treatment of biliary dyskinesia.

Abstract Background The outcome of laparoscopic cholecystectomy for patients who present with “classic” biliary colic without evidence of cholelithiasis or acute inflammation (biliary dyskinesia) is not well documented. This study evaluates whether a cholecystokinin dimethyl iminodiacetic acid (CCK-HIDA) scan can predict relief of symptoms in this group of patients. Methods Patients who underwent laparoscopic cholecystectomy after a normal ultrasound and with an abnormal dimethyl iminodiacetic acid scan were retrospectively reviewed. Symptomatic improvement was correlated with degree of dyskinesia, histologic findings, sex, and age. Results One hundred seventy-six patients were studied and 69% were available for followup at a mean interval of 16 months. One hundred fourteen patients (94%) had complete or partial relief of symptoms. No correlation was found between degree of relief and degree of impaired ejection (31% to 50% versus Conclusions Abnormal cholecystokinin dimethyl iminodiacetic acid scan effectively predicts relief of symptoms in patients undergoing laparoscopic cholecystectomy for biliary dyskinesia.
Msx1/Bmp4 genetic pathway regulates mammalian alveolar bone formation via induction of Dlx5 and Cbfa1.

In the developing mammalian tooth, the cranial neural crest derived dental mesenchyme consists of the dental papilla and dental follicle. The dental papilla gives rise to odontoblasts and dental pulp and the dental follicle gives rise to the periodontium, including the osteoblasts that contribute to the alveolar process. The alveolar process is a specialized intramembranous bone that forms the primary support structure for the dentition. The Msx1 gene controls many aspects of craniofacial development, as evidenced by craniofacial abnormalities seen in Msx1−/− mice, including the arrest of tooth development and the absence of the alveolar bone. Previous studies demonstrated that ectopic expression of Bmp4, a downstream target of Msx1, in the Msx1−/− dental mesenchyme rescued alveolar bone formation. Here we confirm an early requirement of BMP activity for alveolar bone formation. We show that the expression of Cbfa1 and Dlx5, two genes encode transcription factors that are critical for bone differentiation, overlaps with that of Msx1 and Bmp4 in the developing tooth and alveolar process. We have demonstrated that Dlx5 and Cbfa1 expression is down-regulated in Msx1−/− dental mesenchyme and that Msx1 and Bmp4 expression are unaltered in Cbfa1−/− mice. These data place Dlx5 and Cbfa1 downstream from the Msx1/Bmp4 in the genetic pathway that regulates tooth development. Ectopic expression of Bmp4 in Msx1 mutants restores the expression of Dlx5, but not Cbfa1, in the dental mesenchyme, and rescues the expression of both Dlx5 and Cbfa1 in the developing alveolar bone. Therefore, the early expression of Cfba1 in the dental mesenchyme appears dispensable for the development of the alveolar bone. Taken together with in vitro gene induction studies, our results demonstrate that BMP4 controls Dlx5 expression in dental mesenchyme, and functions upstream to both Dlx5 and Cbfa1 to regulate alveolar bone formation during tooth development.
Energy Transfer Observed in Live Cells Using Two-Dimensional Electronic Spectroscopy

Two-dimensional electronic spectroscopy (2DES) elucidates electronic structure and dynamics on a femtosecond time scale and has proven to be an incisive tool for probing congested linear spectra of biological systems. However, samples that scatter light intensely frustrate 2DES analysis, necessitating the use of isolated protein chromophore complexes when studying photosynthetic energy transfer processes. We present a method for conducting 2DES experiments that takes only seconds to acquire thousands of 2DES spectra and permits analysis of highly scattering samples, specifically whole cells of the purple bacterium Rhodobacter sphaeroides. These in vivo 2DES experiments reveal similar timescales for energy transfer within the antennae complex (light harvesting complex 2, LH2) both in the native photosynthetic membrane environment and in isolated detergent micelles.
Proton and carbon NMR chemical-shift assignments for [β-d-Fruf-(2 → 1)]3-(2 ↔ 1)-α-d-Glcp (nystose) and [β-d-Fruf-(2 → 1)]4-(2 ↔ 1)-α-d-Glcp (1,1,1-kestopentaose) from two-dimensional NMR spectral measurements

The proton chemical-shift assignment of nystose (1) [beta-D-fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2-->1)-beta-D- fructofuranosyl-(2 1)-alpha-D-glucopyranoside], was determined by using two-dimensional (2D) NMR spectral methods, and corrections of, and additions to the previous 13C chemical-shift assignments were made. The 1H peak of H-1 of the D-glucosyl group was determined by its chemical shift. Signals from fructose-1 were distinguished by the observation of long-range C-H coupling between H-1 of the D-glucosyl group and C-2 of fructose-1. The distinction between fructose-2 and fructose-3 was made by the different 1JCH coupling patterns between C-1 and H-1. Assignments of 13C and 1H chemical shifts of the related dp 5 compound, beta-D-fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2-->1)-beta-D- fructofuranosyl-(2-->1)-beta-D-fructofuranosyl-(2 1)-alpha-D-glucopyr anoside (1,1,1-kestopentaose, 2) are also reported here with comparisons of its spectral data with the data from 1-kestose, nystose and inulin. Based on differences in 13C chemical shifts, it appears that the chemical environment of inulin is not attained in nystose, and only partially attained in 1,1,1-kestopentaose.
A pilot study of the dimensions of disciplinary culture among engineering students

Hofstede's theory of national cultures has been widely used to analyze cultural differences. In this pilot study we describe our experiences applying an instrument based on Hofstede's work to determine whether his dimensions of national cultures can be mapped to academic disciplines. In this paper, we present information about Hofstede's model as well as critiques of both the model and the instrument used. We also report initial results of a pilot survey based on Hofstede's model that we administered to a sample of 687 undergraduate engineering students. Preliminary results show that the instrument is reliable and valid; in addition, we present preliminary results regarding how different engineering majors map to Hofstede's cultural dimensions.
Do inbreeding depression and relative male fitness explain the maintenance of androdioecy in white mangrove, Laguncularia racemosa (Combretaceae)?

Summary • Mathematical models predict that to maintain androdioecious populations, males must have at least twice the fitness of male function in hermaphrodites. To understand how androdioecy is maintained in Laguncularia racemosa (white mangrove), outcrossing, inbreeding depression, and relative male fitness were estimated in two androdioecious populations and one hermaphroditic population. • Outcrossing was estimated based on length of pollinator foraging bout and pollen carryover assumptions. Inbreeding depression was measured at three life stages: fruit set, seedling emergence, and seedling survivorship. The relative fitnesses of males and the male component of hermaphrodites were compared at these three stages and at the pollen production stage. Male frequency predictions generated by Lloyd’s model were compared with observed frequencies in two androdioecious subpopulations. • Outcrossing estimates were moderate for all populations (0.29‐0.66). Inbreeding depression varied among populations (‐0.03‐0.86), but the strength of inbreeding depression did not increase with male frequency. Males produced significantly more flowers/inflorescence than hermaphrodites, but pollen production/flower did not differ. Male and hermaphroditic progeny did not differ significantly at other life
Exciton percolation. II: Naphthalene 1B2u supertransfer

Abstract The exciton percolation theory has been tested for the migration of the lowest singlet exciton in our model organic alloy system at low temperature (2 K): binary isotopic mixed crystals of naphthalene (C 10 H 8 —C 10 D 8 ), with an added exciton sensor (supertrap) of betamethylnaphthalene (about 10 −3 mole fraction). At these relatively high sensor concentrations the system's migration dynamics are described quantitatively by the simple limiting case of supertransfer , i.e. by a dynamic percolation formulation of Hoshen and Kopelman that depends only on the concentrations and interaction topology of the ternary crystal. Experimentally, the exciton's migration dynamics is monitored by fluorescence spectra, taken under controlled conditions (crystal quality, purity, concentration, excitation and temperature). The effects of exciton tunneling (superexchange), exciton—phonon coupling, coherence, exciton delocalization and non-equilibrium chemical solubility are considered. We show that a complete concentration study of this simple energy transport model system reveals four kinds of exciton transfer regions, but only one (above the critical guest site percolation concentration) with long ranged, multistep, direct guest exciton transport. The same study, on the low concentration side, yields relative trapping efficiencies and thus eliminates the need for adjustable parameters. The substitutional randomness of the isotopic mixed crystal is confirmed, as well as the short range nature of the 1 B 2u exciton interactions and the dominance of the interchange equivalent, nearest neighbor, pairwise (molecular) excitation ( 1 B 2u ) exchange integrals in the pure, perfect, low-temperature, naphthalene crystal. Our present exciton percolation study is also relevant to the primary energy transport process in heterogeneous photosynthetic units.
Morphology and distribution of type II supraependymal cells in the third ventricle of the guinea pig.

The distribution and morphology of phagocytic (Type II) supraependymal cells residing within the third ventricle of the guinea pig were investigated by scanning electron microscopy. Type II supraependymal cells were restricted to nonciliated regions of the ventricle. They were most numerous on the choroid plexus, abundant within the infundibular recess and were present on the ventricular floor in the region of the median eminence. Morphologically, they were characterized by a soma from which pseudopodia-like processes extended to the subjacent ependyma. Type II cells varied in configuration according to their location. Those residing on the choroid plexus typically had irregular somas and possessed processes that generally terminated in finger-like extensions. In contrast, cells on the ventricular floor and within the infundibular recess were stellate and possessed processes that terminated in fan-like cytoplasmic expansions. There were no differences noted in the frequency, distribution or morphology of Type II supraependymal cells in male and female animals. Furthermore, cell frequency did not appear to vary in relation to the estrous cycle. The data suggest that the pleomorphism exhibited by Type II supraependymal cells may reflect adaptations to diverse environmental conditions present within different regions of the third ventricle.
Effects of Equivalence Ratio and Dwell Time on Exhaust Emissions From an Experimental Premixing Prevaporizing Burner

A flame-tube study was performed to determine the effects of equivalence ratio and residence time on exhaust emissions with premixed, prevaporized propane fuel. Nitrogen oxides emissions as low as .3 g NO2/kg fuel were measured with greater than 99% combustion efficiency at 800 K inlet temperature and an equivalence ratio of .4. For a constant combustion efficiency, lower nitrogen oxides emissions were obtained by burning very lean with relatively long residence times than by using somewhat higher equivalence ratios with shorter times.
Amikacin-induced alterations in the structure of gram-negative bacilli.

Abstract Exposure of some species of Enterobacteriaceae and of Pseudomonasaeruginosa to amikacin results in structural alterations which coincide with a decrease in the number of colony forming units. Escherichiacoli when exposed to amikacin at a concentration twice the minimum inhibitory concentration for 2 hr shows a reduction in the number of ribosomes in the center of the cell and an aggregation of nuclear material in a peculiar concentric pattern we called "tornado image." After 2–4 hr of exposure to amikacin at concentrations of two to five times the minimal inhibitory concentration, all species tested showed in addition to alterations in the distribution of ribosomes, ruptures in the cytoplasmic membrane, damaged cell walls, and in some instances complete loss of cellular shape. It appears that amikacin produces a lytic death of bacteria.
Selective Phototoxicity Using Monoclonal Antibody-Chromophore Conjugates

Increased selectivity and efficacy in photochemotherapy may be achieved by the use of monoclonal antibodies (Mabs) bound to chromophores. Due to their antigen recognition capabilities, Mabs can potentially deliver higher concentrations of chromophores to target tissue while sparing normal tissue. A brief review of the current status of antibody-mediated selective phototoxicity is presented.
Specification Error Tests and Alternative Functional Forms of the Aggregate Production Function

Abstract Tests for specification error are applied to a number of alternative production function models using aggregate U. S. manufacturing data by states for the year 1957. On the basis of the test results, the CES production function is tentatively chosen in preference to the Cobb-Douglas, variable elasticity, one form of the generalized production function, and a simple quadratic in capital and labor. The CES function estimated in this case gives indications of increasing returns to scale and of having an elasticity of substitution parameter greater than one.
2-D network model simulations of miscible two-phase flow displacements in porous media: Effects of heterogeneity and viscosity

Abstract There are long-standing uncertainties regarding the relative significance of the role of porous medium heterogeneities vs. the role of fluid properties in determining the efficiencies of various strategies for fluid injection into porous media. In this paper, we study both the role of heterogeneities and of viscosity ratio in determining the characteristics of miscible, two-phase flow in two-dimensional (2-D) porous media. Not surprisingly, we find that both are significant in determining the flow characteristics. For a variety of statistical distributions of pore-throat radii, we find that the coefficient of variation (the ratio of the standard deviation of the radii to their mean) is a reliable predictor of the injected fluid saturation as well as the width of the interfacial region. Consistent with earlier results, we find that viscosity ratio causes a crossover from fractal viscous fingering to standard compact flow at a characteristic crossover time which varies inversely with viscosity ratio. The studies in this paper show that the power law relating characteristic time to viscosity ratio does not depend upon the distribution of pore-throat radii or upon the connectivity (coordination number) of the medium each of which affects the porosity; this suggests that the power law may be entirely independent of the structure of the porous medium. This power law relationship leads to a robust dependence of the flow properties upon a particular ratio of the saturation to a given power of the viscosity ratio. This dependence is reminiscent of the empirical “quarter power mixing rule” in three dimensions. As such, this work provides a physical understanding of the origin and limitations of this empirical mixing rule.
Laparoscopic gastrostomy using T-fasteners as retractors and anchors.

Most feeding or venting gastrostomies can be placed percutaneously via gastroscopy. Laparotomy is required if gastroscopy is not possible—for example, in patients with esophageal strictures or large tumors. We have developed a new technique of laparoscopic gastrostomy, and used it successfully in three patients. The key to this technique is the T-fastener, a nylon suture attached to a metal T-bar, which is introduced via a slotted needle percutaneously and dislodged inside the stomach lumen. Four T-fasteners secure the stomach wall to the anterior abdomen. A balloon catheter gastrostomy tube is then placed over a J-wire through the center of these T-fasteners. This technique requires no gastroscopy or intracorporeal suturing and needs only one port for the laparoscope. It is safe and simple and can be used for patients who require a gastrostomy in whom gastroscopy is not possible or is risky.
A Faber–Krahn inequality for solutions of Schrödinger’s equation

Abstract We consider nontrivial solutions of − Δ u ( x ) = V ( x ) u ( x ) , where u ≡ 0 on the boundary of a bounded open region D ⊂ R n , and V ( x ) ∈ L ∞ ( D ) . We prove a sharp relationship between ‖ V ‖ ∞ and the measure of D , which generalizes the well-known Faber–Krahn theorem. We also prove some geometric properties of the zero sets of the solution of the Schrodinger equation − Δ u ( x ) = V ( x ) u ( x ) .
Recent progress in development of mid-IR interband cascade lasers

Type-II interband cascade lasers are promising in becoming efficient and compact mid-infrared light sources for many applications. Significant progress toward such a goal has recently been made in terms of lowering their threshold current densities and raising operation temperature. Also, continuous wave operation of single-mode distributed feedback interband cascade lasers has been demonstrated. We review the recent progress of the Sb-based mid-IR interband cascade lasers and present some latest results.
Pierre Vergniaud: Theorist of the French revolution

One characteristic of Pierre Vergniaud's speeches, particularly those of 1791–1792, was his tendency to argue from his own definitions of the catchwords of the day: rights, social contract, and sovereignty. These definitions served as points of departure from which his political ideology emerged. Hence, Vergniaud, like his American contemporary James Wilson of Pennsylvania, was a theorist of revolution, not a popular exhorter of it.