cssi/SciSciGPT-SciSciNet huggingface dataset:
Identity-Based access control for ad hoc groups

The proliferation of group-centric computing and communication motivates the need for mechanisms to provide group access control. Group access control includes mechanisms for admission as well as revocation/eviction of group members. Particularly in ad hoc groups, such as peer-to-peer (P2P) systems and mobile ad hoc networks (MANETs), secure group admission is needed to bootstrap other group security services. In addition, secure membership revocation is required to evict misbehaving or malicious members. Unlike centralized (e.g., multicast) groups, ad hoc groups operate in a decentralized manner and accommodate dynamic membership which make access control both interesting and challenging. Although some recent work made initial progress as far as the admission problem, the membership revocation problem has not been addressed. In this paper, we develop an identity-based group admission control technique which avoids certain drawbacks of previous (certificate-based) approaches. We also propose a companion membership revocation mechanism. Our solutions are robust, fully distributed, scalable and, at the same time, reasonably efficient, as demonstrated by the experimental results.
Multi-Scale Plasma Turbulence in the Diffuse Interstellar Medium

I discuss how radioastronomical observations can provide information on the turbulence that governs the propagation of cosmic rays in the Galaxy. Interstellar radio wave propagation effects, collectively referred to as interstellar scintillations, yield information on the spatial power spectra of fluctuations in plasma density and magnetic field. Results of relevance to cosmic-ray physics are the existence of interstellar turbulence over a wide range of spatial scales (which can thus interact with a wide range of cosmic ray energies), the detection of magnetic field fluctuations in association with this turbulence, and a change in the nature of the turbulence on spatial scales of about 3.5 parsecs. A number of mysteries remain, such as the apparent suppression of Fast Magnetosonic wave generation by the interstellar turbulence.
Cross-Cultural Comparison Of Stigma Toward Mental And Neurological Disorders (P6.002)

OBJECTIVE: Investigate the prevalence of stigma toward neuropsychiatric illnesses and its influencing factors across different cultures. BACKGROUND: The high social and economic burden of neuropsychiatric disorders may be further compounded by stigma. A previous study in a Hispanic community evaluating prevalence and variables associated with stigma is now expanded to study and compare results with two populations in the United States. DESIGN/METHODS: One population from Nicaragua and two from Nebraska were assessed. Participants were asked to view three videos, depicting epilepsy, schizophrenia, and dystonia. Each video was followed by a short questionnaire assessing stigma. Participants were then given additional information about the patient with dystonia and the questionnaire was repeated. Statistical analysis used Exact Chi-square, McNemar test, and more complex logistic regression models. Significance was established by a p<0.05. RESULTS: 273 participants (65.9% female) from three sites: a community health center in Leon, Nicaragua (92 participants), OneWorld Community Health Center in Omaha, Nebraska (85 participants, predominantly Hispanic), and Clarkson West Family Medicine Clinic in Omaha, Nebraska (96 participants, mostly non-Hispanic). Many variables were assessed including age, gender, location, level of education, and ethnic background. The results showed a complex relationship between these variables and level of stigma. Prevalence of stigma was alarming, with 50-to-90% of responses showing some degree of prejudice against neuropsychiatric disorders. Overall, significant differences existed between the three populations, with only minor differences between various ages and genders. Learning more about the people in the videos decreased stigma (p<0.01), a proof that unjustified preliminary harsh judgment is common. CONCLUSIONS: Stigma toward neuropsychiatric disorders is alarmingly common across all three communities studied. Age, gender, and level of education did not correspond to differences in prejudice, underlying the complexity of this problem. More studies are needed to evaluate the true implications of stigma toward neuropsychiatric diseases. Study Supported by: Carole Davis Memorial Fund Disclosure: Dr. Gharzai has nothing to disclose. Dr. Harney has nothing to disclose. Dr. Higgins has nothing to disclose. Dr. High has nothing to disclose. Dr. Xu has nothing to disclose. Dr. Reynolds has nothing to disclose. Dr. Inciarte has nothing to disclose. Dr. Torres-Russotto has received personal compensation for activities with the American Parkinson Disease Foundation, Lundbeck, Teva Neuroscience, Huntington Disease Society of America, Parkinson Disease Foundation, and Merz Pharma.
Increase in the size of chick embryo cells upon cultivation in serum-containing medium

Summary Chick embryo cells undergo a large increase in size and in size heterogeneity when placed underin vitro cultivation. The rate of increase in size is proportional to the concentration of serum in the medium and is largely due to the α- and β-globulins of the serum. The increase in size is paralleled by an increase in the protein content per cell. It is not due to a selection of the larger cells from the original population.
Bound states and the Szegő condition for Jacobi matrices and Schrödinger operators

For Jacobi matrices with a_n=1+(−1)^nαn−γ, b_n=(−1)^nβn−γ, we study bound states and the Szegő condition. We provide a new proof of Nevai's result that if γ>12, the Szegő condition holds, which works also if one replaces (−1)^n by cos(μn). We show that if α=0, β≠0, and γ<12, the Szegő condition fails. We also show that if γ=1, α and β are small enough (β^2+8α^2<1/24 will do), then the Jacobi matrix has finitely many bound states (for α=0, β large, it has infinitely many).
Morphological changes associated with furazolidone-induced cardiomyopathy: effects of digoxin and propranolol

Summary The purpose of the present study was to examine light microscopic data qualitatively as well as quantitatively from an animal model of dilated cardiomyopathy in the turkey. A previous study reported the gross cardioprotective effect of propranolol and the lack of cardioprotection with digoxin in furazolidone-induced cardiomyopathy. It was therefore important to define whether the response of the myocardium to therapeutic interventions differed from the structural responses seen in their absence. In furazolidone-treated birds with resultant cardiac dilation there was myocyte hypertrophy, enlargement of nuclei and reorientation of subepicardial myocardial fibres. Similar changes were noted in birds receiving both furazolidone and digoxin. However, birds receiving propranolol, a non-selective beta-receptor antagonist, and furazolidone did not demonstrate a hypertrophic response or reorientation of fibres. These data indicate that propranolol maintained myocardial morphology and morphometry and thus prevented the structural sequelae of the disease, which is a better achievement of therapy than simple arrest of the progress. A role for intracellular calcium is implied. The cardioprotective effect seen with beta blockade suggests that membrane related events may lead to the contractile dysfunction that results in dilation and cardiac hypertrophy.
Some Exact Results on the Superpotential from Calabi-Yau Compactifications

Abstract We prove that certain superpotential couplings in compactified string theories are given exactly by the values calculated at sigma-model tree level. In particular, the 27 3 coupling in (2,2) compactifications is a coupling of this sort. We explicitly check our results by examining the couplings in an exactly soluble model proposed by Gepner as a particular point in the moduli space of (2,2) compactifications on Y 4; 5 . We thus determine the exact values of the normalized 27 3 couplings for any value of the radius of Y 4; 5 .
Inhibition of mammalian ribonucleases by endogenous adenosine dinucleotides

The most potent low molecular weight inhibitors of pancreatic RNase superfamily enzymes reported to date are synthetic derivatives of adenosine 5(')-pyrophosphate. Here we have investigated the effects of six natural nucleotides that also incorporate this moiety (NADP(+), NADPH, ATP, Ap(3)A, Ap(4)A, and Ap(5)A) on the activities of RNase A and two of its homologues, eosinophil-derived neurotoxin and angiogenin. With eosinophil-derived neurotoxin and angiogenin, Ap(5)A is comparable to the tightest binding inhibitors identified previously (K(i) values at pH 5.9 are 370 nM and 100 microM, respectively); it ranks among the strongest small antagonists of RNase A as well (K(i)=230 nM). The K(i) for NADPH with angiogenin is similar to that of Ap(5)A. These findings suggest that Ap(5)A and NADPH may serve as useful new leads for inhibitor design. Examination of inhibition under physiological conditions indicates that NADPH, ATP, and Ap(5)A may suppress intracellular RNase activity significantly in vivo.
Phonological deficits in children with developmental language impairment.

Abstract The phonological characteristics of children with developmental language impairment were compared to those of a group of younger, normally developing children matched for general linguistic ability. Similar patterns of consonant accuracy were observed (nasals > stops > stops in clusters > continuants), and the errors of both groups could be described in terms of simplification processes commonly reported in the literature on normal child phonology. Evidence of speech characteristics suggestive of perceptual or motor programming deficits was limited.
Fermi-Surface Structure and Field Ionization

Field ionization at metal surfaces as rearrangement collision, considering anisotropic electron tunneling probabilities produced by Fermi surface
Erratum to: Further evidence for addition and numerical competence by a Grey parrot (Psittacus erithacus)

The online version of the original article can be found under doi: 10.1007/s10071-012-0470-5 .
Observed effects of mechanical grain-size reduction on the domain structure of pyrrhotite

Abstract The magnetic mineral grains that carry natural remanent magnetization (NRM) in rocks can undergo changes in volume, chemical composition, or both. Because domain structure is a function of particle size, composition, and the dominant anisotropy, a change in these properties could trigger changes in the number of domains, drive domain walls to new positions, and thus reset natural remanence. The manner in which active grain-size reduction alone affects domain state has not been studied, however. To address this problem, we have observed Bitter patterns on two mutually perpendicular surfaces of natural pyrrhotite grains, whose sizes were reduced mechanically in the laboratory. Both one-dimensional and two-dimensional thinning experiments were performed. Each grain was thinned until at least one dimension was approximately 20–50% of its original size. Domain widths, the overall positions of surviving walls, and even many small-scale details in the shapes of curved walls were remarkably insensitive to thinning. These results lead to three conclusions. First, local energy minimum (LEM) domain states in pyrrhotite could be stable across a wide range of grain sizes and shapes. Second, defects that pin domain walls could inhibit LEM–LEM transitions by impeding the wall motions required for such transitions. Third, in pyrrhotite the defects which prevent walls from adjusting to thinning-induced changes in demagnetizing field appear to be densely and rather homogeneously distributed across a wall’s surface, rather than being volumetrically rare. When viewed together, these results strongly suggest that an NRM direction, originally carried by two-domain grains, would survive grain-size attrition as the two-domain parents were reduced to stable single-domain daughters.
Selection and properties of Leishmania tropica resistant to 10-propargyl-5,8-dideazafolate, an inhibitor of thymidylate synthetase

Leishmania tropica promastigotes have been selected which are highly resistant to the thymidylate synthetase (TS) inhibitor, 10-propargyl-5,8-dideazafolate (CB3717). As reported for L. tropica resistant to methotrexate (MTX), an inhibitor of dihydrofolate reductase (DHFR), CB3717-resistant organisms have high levels of the bifunctional TS-DHFR and amplified DNA sequences. TS-DHFR represents up to 2% of the protein in cell extracts and does not appear to have a structural alteration that contributes to drug resistance. The amplified unit of DNA has a uniform restriction-site map throughout the selection and is nearly identical to the 30 kb amplified unit of R-region DNA found in MTX-resistant cells, except for a small increase in size of the fragment that contains a junction believed to be the site of DNA rearrangements generated during amplification. CB3717-resistant cells do not possess the amplified H-region DNA found in MTX-resistant cells. The amplified DNA in cells resistant to low levels of CB3717 appears as a 30-kb extrachromosomal circle, similar to the amplified DNA of MTX-resistant organisms. In cells resistant to higher levels of drug, the amplified DNA appeared as higher molecular weight forms. When resistant cells were grown in the absence of drug, the amplified DNA and levels of TS-DHFR gradually fell to approximately 10% of the resistant levels. These findings support the proposal that the R-region DNA possesses the sequences that encode the bifunctional protein.
Canonical equation sets for classes of concordant polytopes

Abstract For natural polytopes presented by means of a combinatorial description, we develop minimal sets of equations describing their affine hulls. Our approach extends the spectral methodology used to determine the dimension of a polytope.
Symphysectomy in the Cat and use of a Steel Insert to Increase Pelvic Diameter

— A 3–year-old castrated male blue point Siamese cat suffering from severe constipation as a result of narrowing of the pelvic canal from an old fracture, was treated successfully by removal of the ventral portion of the pubis and ischium, and placement of a metal insert. Narrowing of the pelvic canal following certain fractures causes numerous complications, among which is the inability to pass normal sized stools. This results in the accumulation of massive amounts of feces in the colon, with straining, pain, and discomfort. The animal remains hunched up, repeatedly tries to defecate and passes only small amounts of mucous and soft stool. Alleviation is obtained by special diet, mineral oil, milk of magnesia, and medications to soften the stool. Often the only effective palliative treatment is repeated enemas given under a short acting anesthesia. A colotomy may be required. The condition can be relieved surgically. Resume—LJn chat siamois a extremites bleues, castre, âge de 3 ans atteint d'une grave constipation comme reultat du retrecissement du canal pelvien apres une fracture ancienne, a ete traite avec succes par le deplacement de la partie ventrale du pubis et de I'ischium et la mise en place d'une prothese metallique. Le retrecissement du canal pelvien apres certaines fractures entraine de nombreuses complications parmi lesquelles il faut compter l'impossibilite de laisser passer des selles de taille normale. Ceci permet l'accumulation de quantites importantes de feces dam le colon, ce qui entraine des efforts de l'animal et des sensations de douleur et d'inconfort. L'animal reste le dos vowst, fait des essais repetes pour defequer et rejette seulement de petites quantites de mucus et de selles dessechees. L'allongement de la douleur est obtenue par un regime special a base d'huile minerale, de lait de magneie et de medicaments pour ramollir les selles. Souvent, le seul traitement palliatif est constitue par des lavements repetes donnes sous anesthesie de courte duree. Une colotemie peut ere necessaire. Cette affection peut etre guerie chirurgicalement. Zusammenfassung— Ein dreijahriger kastrierter Blue-Point-Siamkater litt an starker Konsti-pation infolge einer Verengung des Beckenkanals durch eine alte Fraktur und wurde erfolgreich durch Ischiopubotomie und Anbringung einer Metallbrucke behandelt. Die Verengung des Beckenkanals nach bestimmten Frakturen verursacht zahlreiche Kompli-kationen, zu denen die Undurchlassigkeit fur normaldimensionierten Kot gehort. Dies hat die Ansammlung grosser Mengen von Faeces im Colon mit Dehnungen, Schmerzen und Unbehagen zur Folge. Das Tier halt sich zusammengekrummt und versucht wiederholt, sich zu erleichtern, gibt aber nur kleine Mengen eines schleimigen und weichen Kots von sich. Eine Linderung lasst sich mit besonderer Ernahrung, Paraffinol, Magnesia und koterweichenden Medikamenten erzielen. Oft ist die einzig wirksame lindernde Behandlung die wiederholte Verabreichung von Einlaufen unter kurzpirkender Narkose. Eine Colotomie kann erforderlich sein. Der Zustand lasst sich chirurgisch beheben.
Fetal lamb pulmonary hypoplasia: Pulmonary vascular and myocardial abnormalities

Neonatal pulmonary hypoplasia resulting from a congenital diaphragmatic hernia (CDH) produces hemodynamic changes and morphologic abnormalities of the pulmonary vasculature. To characterize the myocardial and pulmonary vascular status of the fetus with pulmonary hypoplasia, we studied four chronically instrumented, near-term fetal lambs with pulmonary hypoplasia, induced by producing a diaphragmatic hernia. We found an elevation in the pulmonary arterial pressure (control, 43.8 +/- 5.9 mmHg; CDH, 58.8 +/- 9.1 mmHg; p < 0.05), an elevation in the systemic arterial pressure (control, 43.8 +/- 0.48 mmHg; CDH, 58.6 +/- 6.7 mmHg; p < 0.05), and an elevation in the pulmonary vascular resistance (control, 0.47 +/- 0.11; CDH, 3.87 +/- 1.9; p < 0.05). In addition, though the total pulmonary blood flow was reduced (control, 83.5 +/- 32.9 mL/min; CDH, 22.2 +/- 17.6 mL/min; p < 0.05), the blood flow reduction was proportional to the reduction in the lung mass (control, 79.8 +/- 28.1 [in flow per 100-g lung weight]; CDH, 85.4 +/- 71.7). The increase in the pulmonary vascular resistance in relation to the unit lung mass (control, 0.55 +/- 0.33; CDH, 0.99 +/- 0.5) was not as pronounced as its increase in relation to the total pulmonary blood flow.(ABSTRACT TRUNCATED AT 250 WORDS)
Identification of a new sertoli cell metabolite of testosterone: 5α-androstane-3α,16α,17β-triol, by HPLC and GC-MS

Testosterone metabolism by isolated rat Sertoli cells cultured in vitro was investigated using HPLC and GC-MS techniques. Monolayer cultures of Sertoli cells (greater than 90% pure and free of Leydig cells) were incubated for 3-day periods with a stable labeled [2,2,4,6,6-d5]testosterone prepared and used in a 1:1 proportion with unlabeled testosterone as the substrate (5 X 10(-7)M). After incubation, the metabolites were extracted from the media and reacted with oestradiol-antibodies. The antibody-bound components were separated on reverse phase HPLC and the fraction corresponding to oestradiol was analyzed by GC-MS in the form of TMS-ether. One of the metabolites whose mass spectrum contained d0 + d5 species was detected and interpreted to be a triol with a mol. wt of 308. Mass spectra data indicated that this testosterone metabolite is one of the sixteen possible isomers of 3,16,17-trihydroxy androstane. This substance was identified based on the Vm value (27.81) closely resembling that of 5 alpha-androstane-3 alpha,16 alpha,17 beta-triol TMS-ether (Vm reported = 27.78) [1] and when compared directly with synthesized compounds [2-3]. Recently we have demonstrated that similar Sertoli cell preparations contain two 16 alpha-hydroxylases by their ability to convert oestradiol to oestriol [4] and 5 alpha-androstane-3 alpha,17 beta-diol to 5 alpha-androstane-3 alpha,16 alpha,17 beta-triol [3], where the former conversion is not affected by FSH, the latter is significantly stimulated by the presence of FSH. Presence of this new product represents the first example of testosterone conversion to 5 alpha-androstane-3 alpha,16 alpha,17 beta-triol and confirms our previous observation that 16 alpha-hydroxylation of 5 alpha-reduced androgens can occur in the rat testis.
Corneal Astigmatism from Conjunctival Cysts

Two patients had decreasing visual acuity because of corneal astigmatism induced by a conjunctival cyst. In both cases, surgical removal of the cyst resulted in marked improvement because of a reduction in astigmatism. In one case, the cause of decreased visual acuity was unknown for two years; keratometry and a careful examination of the eyelids disclosed the cyst.
Response to intensity of reproduction in mouse lines resistant or susceptible to fescue toxicosis.

Summary Our objective was to examine whether mouse lines divergently selected for response to fescue toxicosis differed in the impact of increasing reproductive intensity on growth, final weight or first and second parity reproduction. Resistant (R) and susceptible (S) females were never mated (NR), mated only once (low reproduction, LR), mated after their first litter was weaned (moderate reproduction, MR) or paired continuously with a male (high reproduction, HR), allowing concurrent pregnancy and lactation. Final weight was significantly higher in mated than in not mated females (31.6 ± 0.6, 35.9 ± 0.6, 36.8 ± 0.6 and 37.2 ± 0.5 g for NR, LR, MR and HR females respectively), but the effect of increasing reproductive intensity was similar in both lines. Neither genetic line, reproductive treatment (LR and MR versus HR) nor their interaction affected first parity traits of dams or pups. In second parity, S dams produced larger litters at birth and weaning and heavier litters at birth than R dams, and MR dams produced more pups and heavier litters than HR dams. As with first litters, however, line by reproductive treatment interactions were not significant or important. Concurrent pregnancy and lactation (the HR treatment) had a similar dampening impact on the expected increase in litter size between first and second parity of both lines. Thus, lines divergently selected for toxicosis response did not differ significantly in the impact of increasing reproductive intensity on dam or pup growth, reproductive output through two parities or mature size. This conclusion should not be generalized. Selection responses in livestock should be monitored to ensure that improvement in one trait does not lead to deterioration in others.
Reaction of Some Rabbit Tissues to Graded Quantities of Trypan Blue

ConclusionsFollowing the administration of total graded doses of 5 to 100 c.cm. of 1% trypan blue to rabbits, the epithelium of the convoluted renal tubules, of the liver, of the pulmonary alveoli and of the adrenal cortex stored dye in decreasing amounts in the order named. The quantity of dye stored in a given tissue varied with the total quantity of dye administered.In highly stained rabbits minute amounts of dye were observed also in the bronchiolar epithelium, in the endothelium of the medullary sinusoids of the adrenal and in the mesothelium of the liver, while larger amounts were present in the germinal epithelium of the ovary.
Self-directed learning: Philosophy and implementation

An account is given of the instruction of university-level introductory physics courses according to an educational framework in which (1) curiosity-driven inquiry is recognised as an essential activity of both science and science teaching; (2) the principal role of the instructor is to provide students the incentive to learn science through their pursuit of personally meaningful questions; (3) the commission of errors is regarded as a natural concomitant to learning and is not penalised; (4) emphasis is placed on laboratory investigations that foster minimally restrictive free exploration rather than prescriptive adherence to formal procedure; (5) research skills are developed through out-of-class projects that involve literature search, experiment, and the modeling of real-world physical phenomena; (6) the precise and articulate use of language is regarded as seminal to communication in science (as it is in the humanities) and is promoted through activities that help develop written and verbal language skills; (7) the evaluation of student performance is based on a portfolio of accomplished work rather than on the outcome of formal testing.
Conjugated polymers in an arene sandwich.

A series of poly(p-arylene butadiynylene)s containing zero, one, and two co-facial π−π interactions per repeat unit were synthesized and characterized. A surprisingly selective and high-yielding Diels−Alder cycloaddition of anthracene and nonsymmetric, sterically hindered anhydrides proved essential to generating the cofacial arene-containing monomers. Single-crystal X-ray structures display nearly parallel cofacial arenes that are within the van der Waals contact distances. The precursor molecules with cofacial arenes undergo reversible one- and two-electron oxidations to the radical cation and dication in CH2Cl2. The anhydrides were converted to N-alkyl imides to increase the solubility. High-molecular weight poly(p-arylene butadiynylene)s were prepared via Pd/Cu(I)/benzoquinone oxidative coupling of the diacetylene monomers. The resulting polymers are highly emissive in solution and thin films. The ionization potentials were measured using ultraviolet photoelectron spectroscopy with thin films. Last, f...
Model-Free Reconstruction of Three-Dimensional Myocardial Strain From Planar Tagged MR Images

A technique is presented for reconstructing a three-dimensional myocardial strain map from a set of parallel-tagged MR images. Radial strains were reconstructed from in vivo data from an anesthetized dog with values between .05 and .1 with a precision of ± .003 for a tag detection accuracy of .1 mm and a tag spacing of 2.5 mm. The reconstruction spatial resolution was demonstrated by reconstructing a localized displacement abnormality. In the circumferential direction, the abnormality that resulted in 5O% displacement attenuation had a full width at half maximum of 5.4 ± .4 mm (mean ± SD). Graphs are presented showing the relationship between the size of an abnormality and the ability of the method to reconstruct that abnormality. The combination of high resolution parallel-tagged MR images and the model-free, coordinate system-free strain reconstruction technique presented in this paper is capable of producing accurate, high resolution strain maps of the myocardium.
Cocaine use and HIV infection in intravenous drug users in San Francisco.

We assessed risk factors for human immunodeficiency virus (HIV) infection in 633 heterosexual intravenous drug users. The HIV seroprevalence was 26% in blacks, 10% in Hispanics, and 6% in whites. Intravenous cocaine use significantly increased the risk of HIV infection, with a seroprevalence of 35% in daily cocaine users (odds ratio, 6.4; 95% confidence interval, 3.0 to 13.3). Black subjects were more likely to use cocaine regularly. Drug use in shooting galleries and sharing of drug injection equipment were also associated with HIV infection and were more common in cocaine users. By multivariate analysis, black race, daily cocaine injection by blacks and Hispanics, all other cocaine injection, heavy use prior to entry into methadone treatment by blacks, and use of drugs in shooting galleries were independent predictors of HIV infection. Methadone therapy was associated with substantial reductions in heroin use and some reduction in cocaine use, but 24% of cocaine users receiving methadone began or increased cocaine injection after entry into treatment. ( JAMA 1989;261:561-565)
Hydroxylation of 10-deoxoartemisinin to 15-hydroxy-10-deoxoartemisinin by Aspergillus niger

The microbial hydroxylation of 10-deoxoartemisinin was investigated with the aim of obtaining preparative yields of hydroxy derivatives. During 14 d at 28 degrees C and pH 6.5 Aspergillus niger transformed 10-deoxoartemisinin (500 mg l(-1)) to 15-hydroxy-10-deoxoartemisinin (26%) and 7beta-hydroxy-10-deoxoartemisinin (69%).
Pencil-like sketch rendering of 3D scenes using trajectory planning and dynamic tracking

Objective: We present a new non-photorealistic rendering method to render 3D scenes in the form of pencil-like sketches. Methods: This work is based on the observation that the dynamic feedback mechanism involving the human visual system and the motor control of the hand collectively generates the visual characteristics unique to hand-drawn sketches. At the heart of our approach is a trajectory planning and tracking algorithm that generate the sketch in multiple layers using a dynamic pen model. On each layer, a set of target strokes are generated from the silhouette lines, edges, and shaded regions which serve as the target trajectory for a closed-loop dynamic pen model. The pen model then produces the rendered sketch, whose characteristics can be adjusted with a set of trajectory and tracking parameters. This process continues in several layers until the tonal difference between the sketch and the original 3D render is minimized. Results: We demonstrate our approach with examples that are created by controlling the parameters of our sketch rendering algorithms. Conclusion: The examples not only show typical sketching artifacts that are common to human-drawn sketches but also demonstrate that it is capable of producing multiple sketching styles.
Radioactive iodine treatment of angina pectoris and congestive heart failure.

This 66-year-old man with angina pectoris for 17 years before treatment, incapacitated for several years despite long periods of rest and other therapy, showed significant improvement 2 months after I131 therapy and for the past 18 months he has been maintained in the hypometabolic state, free of pain despite greatly increased activity.
Monte Carlo simulations in the isoenthalpic-isotension-isobaric ensemble.

We discuss simulations using a recently derived Monte Carlo method which generates the isoenthalpic-isotension-isobaric ensemble or HtN ensemble of classical statistical physics. This method is the Monte Carlo counterpart of the Andersen-Parrinello-Rahman HtN form of molecular dynamics. As an example of the use of HtN Monte Carlo calculations we discuss the calculation of the adiabatic elastic constants and other related thermodynamic properties of a crystalline solid from fluctuation formulas specific to the HtN ensemble and compare with the HtN molecular-dynamics calculation of these same quantities. The agreement of the results with earlier calculations of these quantities using other ensembles supports the inference that our probability density generates the HtN ensemble. For the elastic constants, the HtN Monte Carlo calculations have better convergence properties than the HtN molecular-dynamics calculations but are slower, by at least an order of magnitude, than the ThN and EhN molecular-dynamics and Monte Carlo methods.
Taking charge of self: breast health practices of older rural women.

ABSTRACT The purpose of this grounded theory study was to explore breast health practices of older Vermont women residing in rural communities. Although the three components of breast health-mammography, clinical breast exam, and self-breast exam-are recommended for women 40 years and over, minimal research has empirically analyzed the breast health practices of healthy women to ascertain if, in fact, these procedures are followed, and if so, what the motivation is for doing so. Twelve women, 50–64 years, participated in face-to-face, audiotaped interviews. Data analysis, including line-by-line and constant comparative approaches, occurred concurrently with data collection. Taking Charge of Self, the generated theory, describes participants' engagement in a process of learning how to take charge of their lives. The analysis indicates that health care providers have a powerful role in the lives of women in this age group. With an increasing emphasis on health promotion and disease prevention, health care p...
Quantitative determination of thiourea

Abstract Thiourea treated with alkaline solutions of hydrogen peroxide is converted to urea and the latter determined by means of urease. A procedure for the quantitative determination of thiourea in the presence of proteins and of urea is described. By this method thiourea can be determined in blood serum. The only substances found to interfere with the results were thiourca derivatives.
cGMP signaling as a target for the prevention and treatment of breast cancer

One in eight women in the United States will be diagnosed with invasive breast cancer in her lifetime. Advances in therapeutic strategies, diagnosis, and improved awareness have resulted in a significant reduction in breast cancer related mortality. However, there is a continued need for more effective and less toxic drugs for both the prevention and the treatment of breast cancer in order to see a continued decline in the morbidity and mortality associated with this disease. Recent studies suggest that the cGMP signaling pathway may be aberrantly regulated in breast cancer. As such, this pathway may serve as a source of novel targets for future breast cancer drug discovery efforts. This review provides an overview of cGMP signaling in normal physiology and in breast cancer as well as current strategies being investigated for targeting this pathway in breast cancer.
The solvent denaturation of double-stranded RNA from poliovirus infected HeLa cells.

Abstract A double-stranded RNA intermediate has been implicated in the replication of viruses containing a single-stranded RNA genome for animal ( Montagnier and Sanders, 1963 , Baltimore et al., 1964 ), bacterial ( Weissman et al., 1964 , Kelly and Sinsheimer, 1964 , Nonoyama and Ikeda, 1964 ) and plant ( Shipp and Haselkorn, 1964 ) viruses. In most systems, the duplex nature of this species of RNA has been demonstrated indirectly by its resistance to enzymatic cleavage by RNAase, although hyperchromism ( Ammann, Delius and Hofschneider, 1964 ) and X-ray diffraction ( Langridge, Billeter, Borst, Burdon and Weissman, 1964 ) have been utilized when very large quantities were available. Because of the very high melting temperature (90–105°C) exhibited by these structures, some degradation invariably accompanies melting, making it difficult to assess the physical integrity of the virus-like strand and of its compliment. We present here a method for achieving strand separation under mild conditions which does not degrade the single strands thus released, and permits one to examine the duplex structure for single-strand breaks. Using this method, we show that the replicative form of poliovirus RNA, which sediments as a single species at 20S can be completely transformed into a more rapidly sedimenting species, whose behavior is the same as single-stranded RNA extracted from mature virus, sedimenting at 35S.
High-power laser system multiplexing for x-ray backlighting

Spatial and temporal multiplexing of a 10-TW Nd:glass amplifier chain is described. A method of sharing the laser aperture between an x-ray backlighter pulse and a target heating pulse is demonstrated.
Androgen and estrogen (α) receptor localization on periaqueductal gray neurons projecting to the rostral ventromedial medulla in the male and female rat

The periaqueductal gray (PAG) is involved in many gonadal steroid-sensitive behaviors, including responsiveness to pain. The PAG projects to the rostral ventromedial medulla (RVM), comprising the primary circuit driving pain inhibition. Morphine administered systemically or directly into the PAG produces greater analgesia in male compared to female rats, while manipulation of gonadal hormones alters morphine potency in both sexes. It is unknown if these alterations are due to steroidal actions on PAG neurons projecting to the RVM. The expression of androgen (AR) and estrogen (ERalpha) receptors in the PAG of female rats and within this descending inhibitory pathway in both sexes is unknown. The present study used immunohistochemical techniques (1) to map the distribution of AR and ERalpha across the rostrocaudal axis of the PAG; and (2) to determine whether AR and/or ERalpha were colocalized on PAG neurons projecting to the RVM in male and female rats. AR and ERalpha immunoreactive neurons (AR-IR, ERalpha-IR) were densely distributed within the caudal PAG of male rats, with the majority localized in the lateral/ventrolateral PAG. Females had significantly fewer AR-IR neurons, while the quantity of ERalpha was comparable between the sexes. In both sexes, approximately 25-50% of AR-IR neurons and 20-50% of ERalpha-IR neurons were retrogradely labeled. This study provides direct evidence of the expression of steroid receptors in the PAG and the descending pathway driving pain inhibition in both male and female rats and may provide a mechanism whereby gonadal steroids modulate pain and morphine potency.
Sparse Matrix Computations Arising in Distributed Parameter Identification

A penalized least squares approach known as Tikhonov regularization is commonly used to estimate distributed parameters in partial differential equations. The application of quasi-Newton minimization methods then yields very large linear systems. While these systems are not sparse, sparse matrices play an important role in gradient evaluation and Hessian matrix-vector multiplications. Motivated by the spectral structure of the Hessian matrices, a preconditioned conjugate gradient method is introduced to efficiently solve these linear systems. Numerical results are also presented.
Hemodynamic Sequelae of Cardiac Arrhythmias

The hemodynamic consequences of cardiac arrhythmias depend on various factors, including the ventricular rate and the duration of the abnormal rate, the temporal relationship between atrial and ventricular activity, the sequence of ventricular activation, the functional state of the heart, the irregularity of the cycle length, associated drug therapy, the peripheral vascular vasomotor system, disease in organ systems other than the heart, and the degree of anxiety caused by the disease processes. Sinus bradycardia, even with rates as low as 40 beats/min, may not be associated with significant hemodynamic consequences unless the stroke volume is limited by myocardial or valvular disease, as in acute myocardial infarction. Cardiac output usually, but not invariably, falls when atrial fibrillation replaces normal sinus rhythm, even at comparable ventricular rates, both at rest and during exercise. Similar observations have been made during the development of atrial flutter despite the persistence of effectiv...
Racial/Ethnic Residential Sorting in Spatial Context: Testing the Explanatory Frameworks1

There are four major explanatory frameworks on racial/ethnic segregation and its changes: Assimilation, Stratification, Resurgent Ethnicity, and Market-Led Pluralism. Previous efforts to evaluate the significance of each framework, mainly relying on cross-urban metrics, pay less attention to intraurban residential patterning even though each framework leads to a different expectation about it. In response, this paper examines the validity of each framework in terms of intraurban segregation and changes. Following Brown and Chung's (2006) suggestion, this investigation utilizes a set of local segregation measures—Location Quotient and Local Moran's I—that shows where segregation occurs within a city. They are applied to the Columbus, Ohio MSA for 1990 and 2000. The overall findings support Resurgent Ethnicity and Market-Led Pluralism as the most relevant of the four frameworks.
Role of tumor necrosis factor–α in wound repair in human vocal fold fibroblasts

Objectives/Hypothesis Tumor necrosis factor-alpha (TNF-α) is an inflammatory cytokine and apoptotic molecule that appears to be a mediator in inflammation and fibrosis. The objective of this investigation was to examine the effects of TNF-α on three-dimensional (3D) Carbylan-GSX in vitro cultured human vocal fold fibroblasts (hVFF), to provide insight into the mechanism responsible for improved vocal fold wound healing that has been previous reported with Carbylan-GSX treatment.
Nd, Sr, and Pb isotopic characteristics of Cretaceous intrusive rocks from deep levels of the Sierra Nevada batholith, Tehachapi Mountains, California

The Cretaceous gabbroic to granitic intrusive rocks of the Tehachapi Mountains were emplaced at depths of 25–30 km and thus afford a view of deep processes in the Sierra Nevada batholith. They consist of the ∼115 Ma Tehachapi suite and the ∼100 Ma Bear Valley suite; new zircon U-Pb age data reveal the presence of the latter as far west as Grapevine Canyon. The Nd, Sr, Pb, and O isotopic whole-rock data and zircon Pb inheritance patterns for the bulk of the suites suggest an origin by mixing between depleted mantle-derived magmas and metasedimentary material with a substantial component of old continental material. However, this mixing is not evident in variations between isotopic ratios and chemical and lithologic parameters. This implies that isotopic hybridization of magmas took place deeper than 30 km, and that fractionation processes are likely responsible for the bulk of the chemical variation in this part of the Sierra Nevada batholith. Consideration of the isotopic data in the context of the Sierra Nevada batholith as a whole suggests that the well-known east-to-west isotopic gradients in the batholith may reflect a change in the average isotopic character of the preintrusive framework rather than a change in amount of crustal component. On the other hand, the lack of areal gradients in Sr and Nd isotopic ratios in the main study area may indicate a lack of pronounced gradation at deep levels, at least within the western batholith.
Align and conquer: moving toward plug-and-play color imaging

The rapid evolution of the low-cost color printing and image capture markets has precipitated a huge increase in the use of color imagery by casual end users on desktop systems, as opposed to traditional professional color users working with specialized equipment. While the cost of color equipment and software has decreased dramatically, the underlying system-level problems associated with color reproduction have remained the same, and in many cases are more difficult to address in a casual environment than in a professional setting. The proliferation of color imaging technologies so far has resulted in a wide availability of component solutions which work together poorly. A similar situation in the desktop computing market has led to the various `Plug-and-Play' standards, which provide a degree of interoperability between a range of products on disparate computing platforms. This presentation will discuss some of the underlying issues and emerging trends in the desktop and consumer digital color imaging markets.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Domains and anomalous adsorption isotherms of dipalmitoylphosphatidylcholine membranes and lipophilic ions : pentachlorophenolate, tetraphenylborate, and dipicrylamine

Dipalmitoylphosphatidylcholine (DPPC) vesicles acquire negative surface charge on adsorption of negatively charged pentachlorophenolate (PCP-), and lipophilic ions tetraphenylborate (TPhB-), and dipicrylamine (DPA-). We have obtained (a) zeta-potential isotherms from the measurements of electrophoretic mobility of DPPC vesicles as a function of concentration of the adsorbing ions at different temperatures (25–42 degrees C), and (b) studied the effect of PCP- on gel-to-fluid phase transition by measuring the temperature dependence of zeta-potential at different PCP- concentrations. The zeta-potential isotherms of PCP- at 25, 32, and 34 degrees C correspond to adsorption to membrane in its gel phase. At 42 degrees C the zeta-potential isotherm corresponds to membrane in its fluid phase. These isotherms are well described by a Langmuir-Stern-Grahame adsorption model proposed by McLaughlin and Harary (1977. Biochemistry. 15:1941–1948). The zeta-potential isotherm at 37 degrees C does not follow the single-phase adsorption model. We have also observed anomalous adsorption isotherms for lipophilic ions TPhB- and DPA- at temperatures as low as 25 degrees C. These isotherms demonstrate a gel-to-fluid phase transition driven by ion adsorption to DPPC membrane during which the membrane changes from weakly to a strongly adsorbing state. The anomalous isotherm of PCP- and the temperature dependence of zeta-potential can be described by a two-phase model based on the combination of (a) Langmuir-Stern-Grahame model for each phase, (b) the coexistence of gel and fluid domains, and (c) depression of gel-to-fluid phase transition temperature by PCP-. Within the anomalous region the magnitude of zeta-potential rapidly increases concentration of adsorbing species, which was characterized in terms of a Esin-Markov coefficient. This effect can be exploited in membrane-based devices. Comments are also made on the possible effect of PCP, as an uncoupler, in energy transducing membranes.
Trends in environmental analysis.

This article discusses developments in environmental analytical chemistry that occurred in the years of 2003 and 2004. References were found by searching the ''Science Citation Index and Current Contents''. As in our review of two years ago (A1), techniques are highlighted that represent current trends and state-of-the-art technologies in the sampling, extraction, separation, and detection of trace concentrations, low-part-per-billion and less, of organic, inorganic, and organometallic contaminants in environmental samples. New analytes of interest are also reviewed, the detections of which are made possible by recently developed analytical instruments and methods.
Clozapine, but not olanzapine, disrupts conditioned avoidance response in rats by antagonizing 5-HT2A/2C receptors.

The present study was designed to assess the role of 5-HT2A/2C receptors in the acute and repeated effect of clozapine and olanzapine in a rat conditioned avoidance response model, a validated model of antipsychotic activity. Male Sprague–Dawley rats that were previously treated with either phencyclidine (0.5–2.0 mg/kg, sc), amphetamine (1.25–5.0 mg/kg, sc), or saline and tested in a prepulse inhibition of acoustic startle study were used. They were first trained to acquire avoidance response to a white noise (CS1) and a pure tone (CS2) that differed in their ability to predict the occurrence of footshock. Those who acquired avoidance response were administered with clozapine (10.0 mg/kg, sc) or olanzapine (1.0 mg/kg, sc) together with either saline or 1-2,5-dimethoxy-4-iodo-amphetamine (DOI, a selective 5-HT2A/2C agonist, 1.0 or 2.5 mg/kg, sc), and their conditioned avoidance responses were tested for four consecutive days. After two drug-free retraining days, the long-term repeated effect was assessed in a challenge test during which all rats were injected with a low dose of clozapine (5 mg/kg, sc) or olanzapine (0.5 mg/kg). Results show that pretreatment of DOI dose-dependently reversed the acute disruptive effect of clozapine on both CS1 and CS2 avoidance responses, whereas it had little effect in reversing the acute effect of olanzapine. On the challenge test, pretreatment of DOI did not alter the clozapine-induced tolerance or the olanzapine-induced sensitization effect. These results confirmed our previous findings and suggest that clozapine, but not olanzapine, acts on through 5-HT2A/2C receptors to achieve its acute avoidance disruptive effect and likely its therapeutic effects. The long-term clozapine tolerance and olanzapine sensitization effects appear to be mediated by non-5-HT2A/2C receptors.