cssi/SciSciGPT-SciSciNet huggingface dataset:
Spatial and temporal variation in rocky intertidal community organization: Lessons from repeating field experiments

Abstract The mid-intertidal zone of the western shores of San Juan Island is dominated by beds of the large barnacle, Semibalanus cariosus (Pallas). Although Semibalanus is a competitively dominant barnacle species that can reach a size refuge from predation and potentially monopolize space, more than 50% of the rock surface is bare. Within the barnacle beds, bare space occurs intermingled among the large adult barnacles, which are a few centimeters apart, and in small patches (0.1–1 m2) devoid of adult Semibalanus. The present study builds on previous experiments in order to investigate spatial and temporal variation in the processes maintaining bare space in this community and to evaluate the benefits and limitations of previous experimental information in this system. Working at the same study site over 23 years ago, Dayton (1971) demonstrated that predation by whelks and bulldozing of newly settled barnacles by limpets were important in maintaining bare space in small patches initially cleared of barnacles. Since the focus of this earlier work was on the factors influencing the provision of bare space after a disturbance (e.g., in areas where large barnacles were initially cleared), no experiments were done in intact beds of large barnacles. We repeated Dayton's factorial manipulations of whelks and limpets both under conditions similar to those described in the original study (i.e., small patches cleared of barnacles), as well as in adjacent intact Semibalanus beds to directly test whether the importance of these consumers in maintaining bare space varied with the presence or absence of large adult Semibalanus. A number of ancillary experiments and observations were conducted to investigate potential mechanisms underlying the observed responses. Our results showed that: (1) Under the conditions of the original experiments (small patches), the importance of whelks and limpets in maintaining bare space was strikingly consistent over time; (2) initial experimental conditions, whether the sessile community was left intact or initially cleared, strongly influenced field measures of consumer-prey interactions; (3) the processes maintaining bare space varied dramatically over small spatial scales. Whelks and limpets played key roles in small patches without large Semibalanus, but they had no effect on the maintenance of bare rock within adjacent beds of the large barnacles. In this case, much of our observational and experimental information on predator densities, behavior, and potential physiological stresses was not useful for predicting community dynamics in Semibalanus beds from previous experimental results.
Testing for normality in a probit model with double selection

Abstract This paper develops a normality test for the probit model with double selection using the Lagrange Multiplier (LM) approach based on an Edgeworth expansion. An empirical example involving the health effects of smoking is presented to illustrate the test.
1860 PULMONARY ASSESSMENT OF CHILDREN AFTER CHLAMYDIAL PNEUM0NIA OF INFANCY

We evaluated the pulmonary status of 18 children 7 to 8 years after their hospitalization for chlamydial pneumonia of infancy. Pulmonary function tests (PFT) and respiratory questionnaire results on this group (CT) were compared to those of a control group (CR) comprised of 19 age, race and sex comparable children from the same community, or to values that other investigators have reported for normal children. Significant limitations of expiratory airflow were found in the CT group mean values compared to CR group (FEV1 p = .01; FEV1FVC p 2 SD from reference means) present in 3 of 18 FRC and 13 of 18 RV/TLC ratios. These obstructive patterns were responsive to inhaled isoproterenol. Similarly, the CT group also had a significantly greater number of children with physiciandiagnosed asthma than the control group (6/18 vs 1/19, p<.03). The obstructive PFT abnormalities could not be accounted for by recognized risk factors such as exposure to smoking at home (11/18 vs 12/19 p = NS) or family history of atopy (6/18 vs 4/19 P = NS). Our results show that chlamydial pneumonia of infancy is associated with PFT and respiratory symptom abnormalities 7 to 8 years after recovery from the acute illness.
Role of Subchondral Bone during Early-stage Experimental TMJ Osteoarthritis

Temporomandibular joint osteoarthritis (TMJ OA) is a degenerative disease that affects both cartilage and subchondral bone. We used microarray to identify changes in gene expression levels in the TMJ during early stages of the disease, using an established TMJ OA genetic mouse model deficient in 2 extracellular matrix proteins, biglycan and fibromodulin (bgn(-/0)fmod(-/-)). Differential gene expression analysis was performed with RNA extracted from 3-week-old WT and bgn(-/0)fmod(-/-) TMJs with an intact cartilage/subchondral bone interface. In total, 22 genes were differentially expressed in bgn(-/0)fmod(-/-) TMJs, including 5 genes involved in osteoclast activity/differentiation. The number of TRAP-positive cells were three-fold higher in bgn(-/0)fmod(-/-) TMJs than in WT. Quantitative RT-PCR showed up-regulation of RANKL and OPG, with a 128% increase in RANKL/OPG ratio in bgn(-/0)fmod(-/-) TMJs. Histology and immunohistochemistry revealed tissue disorganization and reduced type I collagen in bgn(-/0)fmod(-/-) TMJ subchondral bone. Early changes in gene expression and tissue defects in young bgn(-/0)fmod(-/-) TMJ subchondral bone are likely attributed to increased osteoclast activity. Analysis of these data shows that biglycan and fibromodulin are critical for TMJ subchondral bone integrity and reveal a potential role for TMJ subchondral bone turnover during the initial early stages of TMJ OA disease in this model.
REP27, a Tetratricopeptide Repeat Nuclear-Encoded and Chloroplast-Localized Protein, Functions in D1/32-kD Reaction Center Protein Turnover and Photosystem II Repair from Photodamage

The goal of this research is elucidation of the molecular mechanism for the unique photosystem II (PSII) damage and repair cycle in chloroplasts. A frequently occurring, irreversible photooxidative damage inhibits the PSII charge separation reaction and stops photosynthesis. The chloroplast PSII repair process rectifies this adverse effect by selectively removing and replacing the photoinactivated D1/32-kD reaction center protein (the chloroplast-encoded psbA gene product) from the massive (>1,000 kD) water-oxidizing and O2-evolving PSII holocomplex. DNA insertional mutagenesis in the model organism Chlamydomonas reinhardtii was applied for the isolation and characterization of rep27, a repair-aberrant mutant. Gene cloning and biochemical analyses in this mutant resulted in the identification of REP27, a nuclear gene encoding a putative chloroplast-targeted protein, which is specifically required for the completion of the D1 turnover process but is not essential for the de novo biogenesis and assembly of the PSII holocomplex in this model green alga. The REP27 protein contains two highly conserved tetratricopeptide repeats, postulated to facilitate the psbA mRNA cotranslational insertion of the nascent D1 protein in the existing PSII core template. Elucidation of the PSII repair mechanism may reveal the occurrence of hitherto unknown regulatory and catalytic reactions for the selective in situ replacement of specific proteins from within multiprotein complexes.
Tyrosine side-chain metabolism in larval and adult cockroaches, Periplaneta americana: Post-ecdysial patterns

Abstract Patterns of tyrosine side-chain metabolism were studied by radiorespirometric techniques in larval and adult cockroaches, Periplaneta americana . Both stages extensively synthesize two-carbon side-chain metabolites during the teneral period for cuticular tanning. Respired 1- 14 CO 2 was nearly equal in both larvae and adults with almost no 2- or 3- 14 CO 2 . After the teneral period, tyrosine decarboxylation decreased and levelled off throughout the remainder of the post-ecdysial period. Larvae metabolized much less tyrosine during this time than did adults. A shift in pathways was indicated a few days after ecdysis by elevation of 2- and 3- 14 CO 2 respired, indicating synthesis of one-carbon side-chain and simple ring metabolites, respectively, the latter in greater quantity. Sustained low level production of N- acetyldopamine and other catecholamines was indicated in both stages throughout the post-ecdysial period but particularly in adults. Metabolism of all tyrosine side-chain carbons was very low just prior to ecdysis, demonstrating that the decarboxylase system for tanning substrate production is not activated until after the insect has emerged from the old cuticle.
Total Variation Wavelet Inpainting

We consider the problem of filling in missing or damaged wavelet coefficients due to lossy image transmission or communication. The task is closely related to classical inpainting problems, but also remarkably differs in that the inpainting regions are in the wavelet domain. New challenges include that the resulting inpainting regions in the pixel domain are usually not geometrically well defined, as well as that degradation is often spatially inhomogeneous. We propose two related variational models to meet such challenges, which combine the total variation (TV) minimization technique with wavelet representations. The associated Euler-Lagrange equations lead to nonlinear partial differential equations (PDE's) in the wavelet domain, and proper numerical algorithms and schemes are designed to handle their computation. The proposed models can have effective and automatic control over geometric features of the inpainted images including sharp edges, even in the presence of substantial loss of wavelet coefficients, including in the low frequencies. Existence and uniqueness of the optimal inpaintings are also carefully investigated.
SAR ATR using learning vector quantization

We address the problems of recognizing 10 types of vehicles in imagery formed from synthetic aperture radar (SAR). SAR provides all-weather, day, or night imagery of the battlefield. To aid in the analysis of the copious amounts of imagery available today, automatic target recognition (ATR) algorithms, which are either template-based or model- based, are needed. We enhanced template-based algorithms by using an artificial neural network (ANN) to increase the discriminating characteristics of 10 initial sets of templates. The ANN is a modified learning vector quantization (LVQ) algorithm, previously shown effective with forward-looking IR (FLIR) imagery. For comparison, we ran the experiments with LVQ using three different sized temporal sets. These template sets captured the target signature variations over 60 degrees, 40 degrees, and 20 degrees. We allowed LVQ to modify the templates, as necessary, using the training imager from all 10 targets. The resulting templates represent the 10 target types with greater separability in feature space. Using sequestered test imagery, we compared the pre- and post-LVQ template sets in terms of their ability to discriminate the 10 target types. All training and test imagery is publicly available from the Moving and Stationary Target Acquisition and Recognition program sponsored by the Defense Advanced Research Projects Agency.
Competitive consequences of interfirm collaboration: How joint ventures shape industry profitability

Recent international business research on international joint ventures focuses on how firms can use such ventures for knowledge access and learning to enhance their competitiveness, thereby increasing competition in the industry. By contrast, research in industrial organization economics has observed that firms can also use joint ventures in various ways to attenuate competition. In this paper, we join these two streams of research to investigate the conditions under which joint ventures reduce or enhance competition by empirically testing the effects of different types of joint ventures on industry profitability. Our results suggest that joint ventures can be pro-competitive or anti-competitive, depending on whether or not they are formed between competing firms, represent foreign market entry, and operate in relatively concentrated industries. Our paper shows the importance of adopting a contingent approach to evaluating the competitive implications of joint ventures, and it also points to the value of reinvigorating international business research on the competitive context and consequences of interfirm collaboration.
Robust focusing optics for high-power laser welding

As available power levels from both fiber and disc lasers rapidly increase, so does the need for more robust beam delivery solutions. Traditional transmissive optics for 1 micron lasers have proven to be problematic in the presence of higher power densities and are more susceptible to focal shift. A new, fully-reflective, optical solution has been developed using mirrors rather than lenses and windows to achieve the required stable focal spot, while still protecting the delicate fiber end. This patent-approved beam focusing solution, referred to as high power reflective focusing optic (HPRFO), involves specialty mirrors and a flowing gas orifice that prevents ingress of contaminants into the optically sensitive region of the assembly. These mirrors also provide a unique solution for increasing the distance between the sensitive optics and the contamination-filled region at the work, without sacrificing spot size. Longer focal lengths and lower power densities on large mass, water-cooled, copper mirrors deliver the robustness needed at increasingly high power levels. The HPRFO exhibits excellent beam quality and minimal focal shift at a fraction of commercially available optics, and has demonstrated consistent reliability on applications requiring 15 kW with prolonged beam-on times.
Relationships between ferruginous bodies and Uncoated asbestos fibers in lung tissue

Abstract Tissue was obtained from two American groups. The tissue was defined by ferruginous body levels of either ≤ 1 000 or > 1 000 ferruginous bodies/g dry weight, and tissue was evaluated by light microscopy and analyzed by analytical transmission electron microscopy. Tissue was bleach digested, and uncoated asbestos fibers were classified with respect to type and size. In addition, some ferruginous body cores were analyzed. There was a wide range of uncoated fibers associated with each ferruginous body. A relationship was found between amosite fibers and ferruginous bodies. Other asbestos types were not associated significantly with the development of ferruginous bodies. Uncoated crocidolite fibers were not detected in these samples; this result further emphasizes the under-appreciated exposure of Americans to amosite. The levels of ferruginous bodies in both groups suggest exposures above those expected in the general population. Uncoated chrysotile levels were below the ranges reported previously f...
A Methodological Study of Perturbation and Additive Noise in Synthetically Generated Voice Signals

There is a relatively large body of research that is aimed at finding a set of acoustic measures of voice signals that can be used to: (a) aid in the detection, diagnosis, and evaluation of voice-q...
Hysterectomy, Oophorectomy, and Cognitive Function in Older Women

Objectives It has been proposed that estrogen deficiency is a cause of memory loss in postmenopausal women. Bilateral oophorectomy leads to an abrupt decrease in gonadal hormone levels including testosterone. Hysterectomy with ovarian conservation may also lead to a decline in ovarian hormones. This study examines the effects of hysterectomy and oophorectomy on cognitive function in a large sample of older, postmenopausal women with and without current estrogen replacement therapy. Design Cross-sectional. Setting Community-based sample in Southern California. Participants Subjects were 885 postmenopausal women aged 60 to 89 who were initially enrolled in the Rancho Bernardo Study between 1972 and 1974 and had a follow-up clinic visit in 1988-91. All were Caucasian, middle to upper-middle class, relatively well educated, and ambulatory. Measurements Participants completed 12 standardized tests of cognitive function in 1988-91. Hysterectomy and oophorectomy status were assessed and use of estrogen therapy was also ascertained and validated. Results Of the 885 women, whose mean age +/- standard deviation was 74.3 +/- 7.5, 225 reported having had a hysterectomy with conservation of one or both ovaries and 190 reported having a hysterectomy with bilateral oophorectomy. Current estrogen use was reported by 35.4%. Among women not using estrogen, there were no significant differences on mean cognitive function scores by hysterectomy and oophorectomy status. Among current estrogen users, after adjustment for age, education, age at menopause, and past estrogen use, those with a hysterectomy and bilateral oophorectomy performed significantly less well on serial sevens and Trails B. These differences, although statistically significant, were small and unlikely to be of clinical significance. No differences in cognitive function were observed between women who had a hysterectomy with ovarian conservation and intact women. Conclusions The present study suggests that, overall, there are no long-term effects of hysterectomy and bilateral oophorectomy on cognitive function and does not support the thesis that estrogen deficiency is associated with poor cognitive function in postmenopausal women.
Multi-gene analysis reveals previously unrecognized phylogenetic diversity in Aliivibrio.

The “Vibrio fischeri species group” recently was reclassified as a new genus, Aliivibrio, comprising four species, Aliivibrio fischeri, Aliivibrio logei, Aliivibrio salmonicida, and Aliivibrio wodanis. Only limited phylogenetic analysis of strains within Aliivibrio has been carried out, however, and taxonomic ambiguity is evident within this group, especially for phenotypically unusual strains and certain strains isolated from bioluminescent symbioses. Therefore, to examine in depth the evolutionary relationships within Aliivibrio and redefine the host affiliations of symbiotic species, we examined several previously identified and newly isolated strains using phylogenetic analysis based on multiple independent loci, gapA, gyrB, pyrH, recA, rpoA, the luxABE region, and the 16S rRNA gene. The analysis resolved Aliivibrio as distinct from Vibrio, Photobacterium, and other genera of Vibrionaceae, and resolved A. fischeri, A. salmonicida, A. logei, and A. wodanis as distinct, well-supported clades. However, it also revealed that several previously reported strains are incorrectly identified and that substantial unrecognized diversity exists in this genus. Specifically, strain ATCC 33715 (Y-1) and several other strains having a yellow-shifted luminescence were not members of A. fischeri. Furthermore, no strain previously identified as A. logei grouped with the type strain (ATCC 29985T), and no bona-fide strain of A. logei was identified as a bioluminescent symbiont. Several additional strains identified previously as A. logei group instead with the type strain of A. wodanis (ATCC BAA-104T), or are members of a new clade. Two strongly supported clades were evident within A. fischeri, a phylogenetic structure that might reflect differences in the host species or differences in the ecological incidence of strains. The results of this study highlight the importance of basing taxonomic conclusions on examination of type strains.
Dynamics in the balance

Physics of Climate. By Jose P. Peixoto and Abraham H. Oort. IOP/AIP: 1992. Pp. 520. £66, $95 (hbk); £31.25, $45 (pbk).
Phonon-mediated entanglement for trapped ion quantum computing

Trapped ions are a near ideal system to study quantum information processing due to the high degree of control over the ion's external confinement and internal degrees of freedom. We demonstrate the key steps necessary for trapped ion quantum computing and focus on phonon-mediated entangling gates. We highlight several key algorithms implemented over the last decade with these gates and give a detailed description of Grover's quantum database search implemented with two trapped ion qubits.
Three-dimensional growth and morphogenesis of mouse submandibular epithelial cells in serum-free primary culture.

Abstract Mouse submandibular epithelial cells can be grown in primary culture using the collagen gel matrix and a chemically defined medium consisting of insulin, transferrin, cholera toxin, and BSA (or FGF). Sustained cell growth leading to a 5–10-fold increase in cell number was observed in less than 2 weeks. In the presence of these additives, clumps of cells proliferate by extending ‘star-like’ projections into the matrix, resulting in three-dimensional outgrowths. The morphology of these outgrowths can be modulated to form a ‘cyst-like’ appearance by deleting BSA and adding cortisol to the basal medium containing insulin, transferrin, cholera toxin and FGF. In brief, a serum-free medium for sustained growth has been devised and a simple manipulation of supplements can modulate the three-dimensional colony morphology in the collagen gel matrix. Finally, the resulting outgrowths can produce epidermal growth factor (EGF) in response to dihydrotestosterone.
Aspartate residue 142 is important for catalysis by ADP-glucose pyrophosphorylase from Escherichia coli.

Structural prediction of several bacterial and plant ADP-glucose pyrophosphorylases, as well as of other sugar-nucleotide pyrophosphorylases, was used for comparison with the three-dimensional structures of two crystallized pyrophosphorylases (Brown, K., Pompeo, F., Dixon, S., Mengin-Lecreulx, D., Cambillau, C., and Bourne, Y. (1999) EMBO J. 18, 4096–4107; Blankenfeldt, W., Asuncion, M., Lam, J. S., and Naismith, J. H. (2000)EMBO J. 19, 6652–6663). This comparison led to the discovery of highly conserved residues throughout the superfamily of pyrophosphorylases despite the low overall homology. One of those residues, Asp142 in the ADP-glucose pyrophosphorylase fromEscherichia coli, was predicted to be near the substrate site. To elucidate the function that Asp142 might play in the E. coli ADP-glucose pyrophosphorylase, aspartate was replaced by alanine, asparagine, or glutamate using site-directed mutagenesis. Kinetic analysis in the direction of synthesis or pyrophosphorolysis of the purified mutants showed a decrease in specific activity of up to 4 orders of magnitude. Comparison of other kinetic parameters, i.e. the apparent affinities for substrates and allosteric effectors, showed no significant changes, excluding this residue from the specific role of ligand binding. Only the D142E mutant exhibited altered K m values but none as pronounced as the decrease in specific activity. These results show that residue Asp142 is important in the catalysis of the ADP-glucose pyrophosphorylase from E. coli.
Ventricular Tachycardia Originating From the Posterior Papillary Muscle in the Left Ventricle A Distinct Clinical Syndrome

Background Several distinct forms of focal ventricular tachycardia (VT) from the left ventricle (LV) have been described. We report a new syndrome of VT arising from the base of the posterior papillary muscle in the LV. Methods and results Among 290 consecutive patients who underwent ablation for VT or symptomatic premature ventricular complexes (PVCs) based on a focal mechanism, 7 patients were found to have an ablation site at the base of the posterior papillary muscle in the LV. All patients had normal LV systolic function and a normal baseline electrocardiogram. The electrocardiogram during VT or PVCs demonstrated a right bundle-branch block and superior-axis QRS morphology in all patients. VT was not inducible by programmed atrial or ventricular stimulation. In 2 patients with sustained VT, overdrive pacing neither terminated VT nor demonstrated any criterion for transient entrainment. Activation mapping localized the earliest site of activation to the base of the posterior papillary muscle in all patients. When Purkinje potentials were recorded at the site of successful ablation, these potentials preceded local ventricular muscle potentials during sinus rhythm. During VT or PVCs, however, the ventricular muscle potential always preceded the Purkinje potentials. After recurrence of VT or PVCs with standard radiofrequency ablation, irrigated ablation was successful in eliminating the arrhythmia in all patients. Over a mean follow-up period of 9 months, all patients have been free of PVCs and VT. Conclusions We present a distinct syndrome of VT arising from the base of the posterior papillary muscle in the LV by a nonreentrant mechanism. Ablation can be challenging, and irrigated ablation may be necessary for long-term success.
COMPARATIVE PERCEPTIONS OF ELEMENTARY, JUNIOR HIGH, AND SENIOR HIGH SCHOOL PRINCIPALS ON SELECTED WORK RELATED VARIABLES

Differences among elementary, junior high, and senior high school principals' perceptions of their administrative task competence; involvement with central office; autonomy; job satisfaction; and length of work week were investigated in relation to social forces confronting the principalship and characteristics of traditional principal preparation programs. Questionnaires mailed to a random sample of 450 principals in rural, urban, and suburban districts yielded a 64 per cent return. All principals perceived themselves competent in administrative tasks. However, suburban principals were more involved with central office and experienced greater autonomy than urban principals. Urban principals worked similar hours and were uniformly satisfied unlike suburban principals who varied significantly in level of satisfaction and hours worked. Revisions in principal preparation programs were mandated.
Comparison of the paraxial-ray approximation and the variational method solutions to the numerical results for a beam propagating in a self-focusing Kerr medium.

The analytic solutions for the amplitude and phase of a cw cylindrically symmetric beam propagating in a self-focusing Kerr medium obtained from the aberrationless paraxial approximation and the variational method are compared with the numerical results of the theory. For beam energies close to the critical focusing value, the variational method expression for the longitudinal phase is shown, except for an extremely small longitudinal distance of propagation, to give better qualitative and quantitative agreement with the numerical solutions. In particular, we confirm the variational method prediction that the regularized phase does not change sign.
On the Theory of Noise in P-N Junctions and Related Devices

A discussion of possible sources of noise in p-n junctions is given. The sources are classified into two groups, the first group constituting noise resulting from fluctuations inherent in the electronic system of a p-n junction, the second group constituting noise caused by a fluctuating quantity which exerts a control over the average flow of current. Noise of the first group is investigated, and it is shown to be a result of concentration fluctuations of the minority carrier. The model used for a p-n junction is characterized by a distribution of localized energy states for the minority carrier in addition to the valence and conduction-band states. The local concentration of the minority carrier, p(x, t), fluctuates by body and surface recombination and by diffusion current flow. Fluctuations in p(x, t) constitute an infinite-dimensional random process. A portion of the paper is devoted to reducing the problem to one in a finite number of variables while retaining the physical features of a p-n junction over the frequency range 0?1/2?Tp. A noise theory is developed on the basis of the resulting lumped parameter description of a p-n junction. The results of the noise theory are summarized in an equivalent circuit and an appropriate noise generator. Noise characteristics of p-n junction rectifiers and transistors are analyzed. The available noise power of a p-n rectifier is voltage dependent, the equation resembling that of Weisskopf for point-contact rectifiers.
Belief Congruence and Prejudice Reduction in an Interracial Contact Setting

Abstract The effect of shared beliefs on the reduction of prejudicial attitudes in an interracial contact setting was investigated. Seventy-four white males from a small rural college participated in discussion groups, each including 3 black and 2 white male confederates instructed to agree or disagee with the subject. Overall prejudicial attitudes toward Blacks were assessed prior to, immediately following, and 6 weeks after the discussion sessions. Greater prejudice reduction and more positive interpersonal perceptions were expected when Blacks and Whites exchanged similar as opposed to dissimilar beliefs. Perceptions of fellow group members, obtained immediately following each session, varied predictably as a function of agreement and disagreement conditions. Overall prejudice reduction, however, was indicated across all interracial contact groups, suggesting that belief congruity was not necessary.
Determination of hepatic uridine 5′-diphosphoglucuronic acid concentration by conjugation with diethylstilbestrol

Abstract A sensitive and reliable assay for uridine 5′-diphosphoglucuronic acid (UDPGA) was developed that involved conjugation of diethylstilbestrol (DES) in vitro. This conjugation reaction is solely dependent upon UDPGA concentration. The assay uses 0.13 M Tris-HCl, pH 7.4, 6.7 mM MgCl 2 , 0.05% Brig 58, 0.25 mg guinea pig liver microsomal protein, 0.13 mM 3 H-DES (0.2 μCi/ml), and 200 μl of boiled 10% liver homogenate in a total volume of 0.5 ml. After a 60-min incubation at 37°C, unconjugated DES is extracted into 5 ml of chloroform and the residual metabolized 3 H-DES in the aqueous phase is determined by liquid scintillation spectrometry. After addition of s-glucuronidase to the aqueous phase, about 90% of the radioactivity could be extracted into chloroform, demonstrating that DES-glucuronic acid is the primary metabolite. Thus, this method easily permits quantitation of UDPGA in rat liver in the 1–10 nmol range.
Loss of Tachyphylaxis and Increased Sensitivity to Angiotensin II in Experimental Vein Grants

Intimal hyperplasia and atherosclerosis have been implicated in the pathophysiology of vein graft failure. Several recent studies have also reported alterations in the vasoreactivity of vein grafts. These alterations in vasoreactivity could contribute to vein graft spasm and lead to graft occlusion. This study examined the vasomotor responses of experimental vein grafts to angiotensin II, the most potent natural vasoconstrictor known. The right carotid artery was divided and bypassed in 12 rabbits with use of the right external jugular vein. The left external jugular vein was used as a control
Large Radius Expansion of Superstring Compactifications

We verify by an explicit perturbative calculation arguments presented recently concerning the existence of compactified solutions of superstring theory in which the spin connection is not embedded in the gauge group in the standard way but the gauge connection is a connection on a more general holomorphic vector bundle over a manifold of SU(3) holonomy.
“incredibilis fama”: Some Remnants of Time in Virgilian Epic

Abstract This paper reads out two very well-known moments in Books 3 and 1 of Virgil’s epic poem in order to address a Virgilian tactic, a poetic strategy, that has not been fully requited in the criticism. These are moments in which the poet chooses to foreground absurd, excessive, epiphenomenal and short-lived things that time seems to bring about. Aeneas, Virgil’s unlikely hero, struggles as much with such moments as he does with all the sworn enemies of the Trojans. He struggles especially with the temptation toward a poignant, nostalgic fixation on his tragic past. He is told that he must become devoted religiously to the greatest of Troy’s enemies, the goddess Juno. It is inside a Carthaginian temple dedicated to Juno that the hero experiences the ‘newness’ that a great work of art is always able to proffer. But Virgil knows that Carthage and Juno’s temple and the works of art themselves will all become follies of time, left in ruins by the romanitas that Aeneas has just been encouraged to prepare.
Evidence for a quantum-vortex-liquid regime in ultrathin superconducting films.

We report the observation of activated dissipation in ultrathin superconducting films near the superconductor-to-insulator transition (SIT) in magnetic fields. The activation energy ${T}_{0}$ scales with the mean field transition temperature, film thickness, and logarithm of the applied field, in qualitative agreement with the activation of defects in a vortex solid. We find ${T}_{0}$ extrapolates to zero at ${H}_{0}$, a field well below the upper critical field implying the existence of a quantum-vortex-liquid regime. We discuss the implications of this result for the magnetic field tuned SIT in this system.
Isolated molecular dopants in pentacene observed by scanning tunneling microscopy

Doping is essential to the control of electronic structure and conductivity of semiconductor materials. Whereas doping of inorganic semiconductors is well established, doping of organic molecular semiconductors is still relatively poorly understood. Using scanning tunneling microscopy, we investigate, at the molecular scale, surface and subsurface tetrafluoro-tetracyanoquinodimethane $p$-dopants in the prototypical molecular semiconductor pentacene. Surface dopants diffuse to pentacene vacancies and appear as negatively charged centers, consistent with the standard picture of an ionized acceptor. Subsurface dopants, however, have the effect of a positive charge, evidence that the donated hole is localized by the parent acceptor counterion, in contrast to the model of doping in inorganic semiconductors. Scanning tunneling spectroscopy shows that the electron potential energy is locally lowered near a subsurface dopant feature, in agreement with the localized hole model.
Echocardiographic features of genetic diseases: part 1. Cardiomyopathy.

Abstract Introduction To The Series Genetic disorders have characteristic cardiovascular manifestations. These cardiovascular abnormalities often are a major determinant of the morbidity and mortality in this patient population. Some characteristics are unique and can be detected with echocardiography. Drs Alizad and Seward have compiled in this series a review of genetic disorders that have recognizable morphologic and/or functional cardiovascular abnormalities. The following topics will be explored, with examples from the database of the Mayo Clinic Echocardiography Laboratory: 1.Cardiomyopathy 2.Storage disease 3.Shunts 4.Connective tissue 5.Tumors 6.Complex cardiovascular defects 7.Complex genetic disorders 8.Organ system
A longitudinal study of the effects of a university human sexuality course on sexual attitudes

Abstract This study tested the hypotheses that students taking a university human sexuality course will have different attitudes over a 2‐year period than students not taking such a course, and more accepting attitudes toward the sexual behaviors of others, over a 2‐year period, than toward their own sexual behavior. Sexual attitudes of 127 human sexuality class students and 114 control class students at the University of Northern Iowa were measured at the beginning of class (pretest), the end of class (posttest), and 2 years after the end of class (follow‐up). There were no pretest differences between the treatment and control groups in university classification, marital status, political affiliation, religious affiliation, sex, age, grade point average, or sexual attitudes. Both hypotheses were supported. Human sexuality students developed more accepting attitudes and became more accepting of behaviors for others compared to behaviors for self. Control group students developed less accepting attitudes a...
In Situ Partial Exfiltration of Rainfall Runoff. II: Particle Separation

Metal elements or other constituents transported in urban and transportation land use rainfall runoff are often adsorbed on or incorporated with entrained particles that are ubiquitous in such runoff. Infiltration.exfiltration can be an effective in situ particle separation and quantity control structural best management practices or low impact development practices allowing runoff to return to soil after passive physical-chemical treatment. The in situ partial exfiltration reactor (PER), which combined the surface straining of the cementitious porous pavement (CPP) layer with filtration of oxide coated sand media beneath, provided control of water quantity and quality. Particle analyses were carried out for both influent and effluent to examine filter efficiency as a function of particle size and hydrology. Influent \Id\Dm\N/d\Dp\N\N ratios suggest that the dominant PER particle separation mechanisms were unsaturated physical.chemical filtration with the CPP layer functioning as a straining surface. Particle size distributions were modeled based on a two-parameter cumulative power-law function. The performance of the PER as a filter is shown to be a function of the unsteady site hydrology. Temporal variation in the filter coefficient and the volumetric particle fraction remaining were directly related to the unsteady influent loading rate. Particle removal efficiency by the PER based on concentration ranged from 71 to 96% on a mass-based concentration and 92.99% on a number based concentration. Results suggest that a properly designed PER can provide effective in situ control for particles and could be combined with or function separately from source control (i.e., pavement cleaning or a mass trading framework).
A117: Demonstration of Antibodies to Multiple Citrullinated Epitopes in the Sera of Patients With Juvenile Idiopathic Arthritis

Background/Purpose: IgG anti-cyclic citrullinated peptide (anti-CCP) antibodies have been identified in the sera of juvenile idiopathic arthritis (JIA) patients and have been associated with more destructive disease. The identity of the target proteins of the citrullinated modification has remained elusive. We attempted to determine the prevalence and significance of different citrullinated epitopes. Methods: We evaluated serum from 96 patients with various subtypes of JIA for the presence of antideiminated (citrullinated) fibrinogen, anti-citrullinated α-enolase, anti-citrullinated and native type II collagen, and anti-vimentin (vim1–16 and vim 59–74) antibodies by enzyme-linked immunosorbent assays. We correlated the presence of the antibodies with anti-CCP and rheumatoid factor (RF) isotypes, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) levels. Results: 31 JIA patients (32%) demonstrated reactivity to anti-citrullinated fibrinogen, 23 (24%) to anti-citrullinated type II collagen, 10 (10.5%) to anticitrullinated vimentin I-16, 9 (9%) to anti-citrullinated α-enolase, and 7 (7.4%) to anti-citrullinated vimentin 59–74 antibodies. One IgM RF positive JIA patient was positive for all 6 of the citrullinated autobodies assayed. The reactivity was higher in those JIA patients positive for IgM RF and IgG/IgM anti-CCP antibodies. Conclusion: The study demonstrates that antibodies to multiple citrullinated epitopes are present in the sera of patients with JIA. A higher percentage of antibodies reacted with citrullinated fibrinogen and citrullinated type II collagen. The more widespread the positivity correlates with more severe disease.
Some applications of the analysis of multivariate normal data with missing observations

Methods are proposed for the analysis of data from a multivariate normal distribution when observations are missing completely at random on some of the variates. Park (1) proved the equivalence of the solutions given by maximum likelihood and generalized estimating equations when data are complete and an unstructured covariance is assumed. He suggested that generalized estimating equations may be used if sample sizes are large relative to the amount of missing data and the estimated covariance matrix is positive definite. We give several examples indicating that the estimating equations give results similar to those of maximum likelihood when smoothing of the covariance matrix to eliminate nonpositive definiteness is not encountered as, for example, under an assumption of exchangeable correlation. Generalized linear models are formulated that are appropriate for a wide class of experimental plans. Contrasts among the means are investigated in terms of robust estimators of the contrasts and their covarianc...
Phosphorescence and zero-field ODMR of biquinoline

Abstract The lowest excited triplet state of 2,2'-biquinoline has been studied by phosphorescence and optically detected magnetic resonance spectroscopy at 2 K in host matrices of n -octane n -decane and biphenyl crystals. The optical and microwave studies reveal a significant effect of the host matrix on the properties of the biquinoline triplet state.
Multiiron Polyoxoanions. Synthesis, Characterization, X-ray Crystal Structure, and Catalytic H2O2-Based Alkene Oxidation by [(n-C4H9)4N]6[FeIII4(H2O)2(PW9O34)2]†

A tetranuclear ferric Keggin sandwich-type heteropolyanion has been synthesized by the reaction of the lacunary species Δ-Na8H[PW9O34] with FeCl2 followed by O2 oxidation in nonaqueous media. The structure of [(n-C4H9)4N]6[FeIII4(H2O)2(PW9O34)2]·4CH3CN·2CH2Cl2·2H2O (TBA-1) was determined by single-crystal X-ray diffraction (orthorhombic, Pbca; R = 0.0693 for 14 963 reflections with Fo > 4σ(Fo)). The compound was further characterized by infrared and UV−visible spectroscopy, electrochemistry, magnetic susceptibility, FAB mass spectrometry (FAB-MS), and elemental analyses. Five lines of evidence are consistent with the FeIII4 oxidation state: (i) valence sum calculations from the X-ray structure (ca. 2.86 ± 0.07 per Fe); (ii) the rest potential from cyclic voltammetry; (iii) charge balance requirements; (iv) titration with CeIV(SO4)2; and (v) oxidation by O2. In contrast to the tetranuclear ferric Wells−Dawson-derived sandwich complex, [FeIII4(H2O)2(P2W15O56)2]12-, TBA-1 can only be prepared from a ferrous...
Enkephalin-immunoreactive neurons in the parvicellular subdivisions of the paraventricular nucleus project to the external zone of the median eminence.

The enkephalin-immunoreactive neurons that project to the external zone of the median eminence were identified on thin paraffin and thick vibratome sections using a combination of retrograde labeling with peripherally administered Fluoro-Gold and immunocytochemistry. The vast majority of the enkephalin-immunoreactive neurons that project to the external zone of the median eminence (ME) reside in the paraventricular nucleus (PVN) of the hypothalamus. Within the PVN, the majority of these hypophysiotropic neurons are located in the medial parvicellular subdivision. while a smaller number can be detected in the anterior and the periventricular subdivisions. Although many enkephalin-immunoreactive neurons are present in other hypophysiotropic areas of the hypothalamus, such as the medial preoptic area, the anterior periventricular area, and the arcuate nucleus, only a few of these can be retrogradely labeled from the ME. These results provide morphological evidence for the key role of paraventricular enkephalin-immunoreactive neurons in the regulation of neuroendocrine functions. © 1992 Wiley-Liss, Inc.
Upwind schemes for the wave equation in second-order form

We develop new high-order accurate upwind schemes for the wave equation in second-order form. These schemes are developed directly for the equations in second-order form, as opposed to transforming the equations to a first-order hyperbolic system. The schemes are based on the solution to a local Riemann-type problem that uses d'Alembert's exact solution. We construct conservative finite difference approximations, although finite volume approximations are also possible. High-order accuracy is obtained using a space-time procedure which requires only two discrete time levels. The advantages of our approach include efficiency in both memory and speed together with accuracy and robustness. The stability and accuracy of the approximations in one and two space dimensions are studied through normal-mode analysis. The form of the dissipation and dispersion introduced by the schemes is elucidated from the modified equations. Upwind schemes are implemented and verified in one dimension for approximations up to sixth-order accuracy, and in two dimensions for approximations up to fourth-order accuracy. Numerical computations demonstrate the attractive properties of the approach for solutions with varying degrees of smoothness.
Effect of startup conditions on drop breakup under shear with inertia

A spherical drop is suspended in another liquid and sheared between parallel walls. Numerical simulations for drop deformation under simple shear typically begin with the drop placed in an established flow. For Stokes flow, the drop evolves in a monotone manner to a stationary state or to breakup. Experimental and numerical studies of this result in a critical curve which delineates the capillary number for breakup at each viscosity ratio. With inertia, however, the history depends on the initial condition. Direct numerical simulations are performed to examine the effect of inertia through the influence of initial data on critical conditions. An abrupt startup induces drop oscillations which are sufficiently large to lead to breakup , while a gentle startup can allow the drop to reach a stationary state. An oscillator model is developed for the manner in which momentum is transferred to the drop and how it is distributed into surface deformation and dissipation as a function of the Reynolds number and capillary number.
Effect of repeated methamphetamine administrations on dopamine and glutamate efflux in rat prefrontal cortex.

Pretreatment with psychostimulants such as methamphetamine (METH) results in augmented mesostriatal dopamine transmission upon a challenge administration of the drug. This effect can be blocked by dopamine antagonists and excitatory amino acid antagonists. However, no direct comparisons have been made with respect to the effects of a low-dose pretreatment regimen of METH on impulse and transporter-mediated dopamine release or to what extent glutamate release is altered by a pretreatment regimen with METH. The purpose of this study was to examine dopamine and glutamate efflux in the prefrontal cortex and striatum in rats pretreated with METH following either high potassium (80 mM) infusion or after a systemic injection of a low dose of METH. Extracellular dopamine and glutamate concentrations in the prefrontal cortex and striatum were measured in vivo by microdialysis. Potassium infusion increased extracellular dopamine and glutamate concentrations to a greater extent in the prefrontal cortex than in the striatum of METH-pretreated rats compared to saline-pretreated controls. A low dose METH challenge significantly increased extracellular dopamine but not glutamate concentrations in both prefrontal cortex and striatum of all animals. Moreover, the acute METH-induced increase in cortical dopamine efflux was significantly greater in rats pretreated with METH. Overall, these data are the first evidence that repeated METH administrations can enhance cortical glutamate efflux and indicate that a low dose pretreatment regimen of METH enhances dopamine transmission in the prefrontal cortex through both transporter and depolarization-induced mechanisms.
Post-War Challenges Facing Women and Girls in Sierra Leone

The conditions that had created the need for human rights educators to address the issues pertaining to women and girls were egregious even before the onset of the war, which raged in Sierra Leone ...