cssi/SciSciGPT-SciSciNet huggingface dataset:
Molecular mechanisms of olfaction

Recent studies provide initial insights into molecular mechanisms of olfaction. The identification of an odorant-sensitive adenylate cyclase which responds to most odorants, affords a second messenger system following odorant interactions with receptors. Cyclic nucleotide- and odorant-gated ion channels have been demonstrated in olfactory cilia, providing signalling systems in place of or in addition to protein phosphorylation. A unique odorant-binding protein localized to nasal mucosa binds odorants in proportion to their odoriferous potencies. Molecular cloning of the isolated protein reveals it to be a member of a family of proteins that serve as carriers for small lipophilic molecules such as retinol and cholesterol. The odorant-binding protein is localized to lateral nasal glands whose secretions are atomized into the tip of the nose where the binding protein presumably interacts with odorants in the inspired air.
Micropillar compression of Al/SiC nanolaminates

Abstract Al/SiC nanolaminates possess an excellent combination of mechanical strength and flexibility. While nanoindentation provides a reasonable estimate of the mechanical properties such as Young’s modulus and hardness of these materials, the stress state under nanoindentation is extremely complex. Micropillar compression has become an attractive method of studying the mechanical properties of materials at small length scales in a nominally homogeneous stress state. In this work, micropillars of Al/SiC nanolaminate were fabricated using focused ion beam milling. Compression testing was carried out using a flat-end nanoindenter head. The actual displacement of the pillar during micropillar compression was deconvoluted by subtracting the “extraneous” displacements of the system. Fractographic analysis showed that Al squeezes out between the SiC layers and that a mutual constraint is observed between the hard and soft layers. Numerical finite element modeling was also employed to provide physical insight into the deformation features of the multilayered pillar structure and agreed well with the experimental observations.
Interference-Aware Power Allocation in Cognitive Radio Networks with Imperfect Spectrum Sensing

This paper investigates the problem of downlink power allocation in a Cognitive Radio (CR) network that operates by opportunistically utilizing vacant licensed Primary User (PU)spectrum, where it is assumed the PU employs an OFDMA scheme. We first analyze the interference to the PU caused by the CR network due to imperfect spectrum sensing and out-of-band (OOB) emissions from CR subcarrier side-lobes. The power allocation algorithm aims to maximize the CR network capacity under interference constraints, while considering the effect of spectrum sensing errors such as false alarm and misdetection probabilities. The power allocation solution for a single-user CR network is the waterfilling criteria with a variable water level in different subcarriers. For a multiple-user CR network, we employ a heuristic algorithm to solve the power allocation problem, with a significantly reduced computational complexity as compared to the optimal solution.
Ethnic Differences in Profiles of Mother–Child Interactions and Relations to Emerging School Readiness in African American and Latin American Children

SYNOPSISObjective. This article examines ethnic similarities and differences in profiles of mother–child interaction qualities for low-income African American and Latin American mothers and associations with preschoolers’ emerging school readiness. Design. Videotaped mother–child interactions were collected at age 2.5 years from a sample of African American (n = 192) and Latin American (n = 210) families. Profiles of maternal behavior were identified in person-centered within-group analyses of five ratings of maternal behavior from the videotaped interactions. Mothering profile groups were examined for relations to child receptive language, behavior problems, and pre-academic school readiness measured at age 3.5 years. Results. Latent class analyses yielded three similar profiles in the two ethnicities identified as Child-Oriented, Directive, and Harsh-Intrusive mothering, and a fourth profile of Withdrawn mothering only among the African American mothers. For African American children, Child-Oriented and...
Improved methods for typing nontypeable isolates of group B streptococci.

Abstract Group B streptococci (GBS) are classified by capsular polysaccharide (CPS) type and by cell surface-expressed proteins (c and R). Isolates lacking detectable CPS are considered nontypeable (NT) although they frequently express surface proteins. Immunological and genetic methods were used to study 91 NT GBS isolates collected during surveillance studies for invasive disease or colonization in pregnant or non-pregnant women and neonates less than seven days of age. CPS production was upregulated by the addition of glucose and sodium phosphate to Todd-Hewitt broth (THB) and cells were extracted using hot HCl or mutanolysin. Extracts were tested with antisera for specific CPS types Ia, Ib, and II – VIII by double immunodiffusion (DD) in agarose. By mutanolysin extraction, 12 (13.2%) of the 91 isolates were typeable. In contrast, only four of these 12 newly typeable isolates tested positive for CPS with the HCl extracts of cells grown in modified THB. DNA was analyzed by pulsed-field gel electrophoresis (PFGE) using SmaI restriction with NT isolates grouped by protein profile to facilitate analysis. PFGE results of the NT isolates were compared to DNA profiles of typeable isolates and were correlated with the DD results. The DNA profiles of the newly typeable isolates were similar to profiles of isolates with corresponding defined CPS type. Of the remaining 78 NT isolates digested by SmaI, 63 (80.8%) had DNA profiles that resembled those of specific types of GBS. These approaches will be useful for classification of NT isolates in continued epidemiological surveillance associated with GBS vaccine trials.
Opportunistic multi-access: multiuser diversity, relay-aided opportunistic scheduling, and traffic-aided smooth admission control

We study multi-access control in opportunistic communication systems, and propose two new schemes to address channel asymmetry and throughput-guaranteed admission control, respectively. We first devise a relay-aided opportunistic scheduling (RAOS) scheme, in which a user can choose to communicate with the base station either directly or using multiple hops (relay transmissions). We develop relay/direct link construction algorithms using either a channel-capacity-based criterion or a throughput-based criterion, and devise opportunistic scheduling schemes accordingly. Our results show that in the presence of channel asymmetry across users, the RAOS scheme performs significantly better than Qualcomm's HDR scheme. Next, we propose a traffic-aided smooth admission control (SAC) scheme that aims to guarantee throughput provisioning. Simply put, in the SAC scheme, the admission decision is "spread" over a trial period, by increasing gradually the amount of the time resource allocated to incoming users. Specifically, using the modified weighted proportional fair (WPF) scheduling, we devise a QoS driven weight adaptation algorithm, and the weights assigned to new users are increased in a guarded manner. Then an admission decision is made based on the measured throughput within a time-out window. A key feature is that we exploit explicitly the traffic information and throughput requirements in devising the back-off time. Our results show that the proposed SAC scheme works well in opportunistic communication systems.
Systemic lupus erythematosus in three ethnic groups: V. Acculturation, health-related attitudes and behaviors, and disease activity in Hispanic patients from the LUMINA Cohort

Objective To assess the relationship between acculturation and clinical, socioeconomic–demographic, and behavioral/psychosocial features in Hispanic patients with systemic lupus erythematosus (SLE) from the LUMINA (Lupus in Minority Populations, Nature versus Nurture) cohort. Methods An empirically derived questionnaire was administered to 67 Mexican American SLE patients participating in a longitudinal study of outcome. This questionnaire inquired about place of birth, upbringing and length of stay in the United States, language (proficiency, usage, and preferences; English/bilingual versus Spanish), type of neighborhood, self-identity, and social interactions. Responses to this questionnaire and an informal interaction with a single bilingual, bicultural Mexican American research assistant were used to generate a score on a 10-cm anchored visual analog scale (VAS) (0 = no acculturation and 10 = maximum acculturation). The responses to the questionnaire were then quantified and scored by a physician who was unaware of the VAS. A composite score was then obtained utilizing 4 of the 6 components of the instrument. The VAS was found to have adequate sensitivity (91%), specificity (88%), and overall predictive value (89%) when the composite score was used as the validity criterion. Therefore, the VAS was used in all subsequent analyses; the median in this VAS separated patients into high and low acculturation groups. The relationship between acculturation and sociodemographic, behavioral/psychosocial (social support, abnormal illness-related behaviors, and helplessness) and clinical variables (disease duration, onset type, number of American College of Rheumatology criteria met, disease activity, and damage) at study entry was then explored. Results Patients in the low acculturation group had fewer years of education, were less likely to have private health insurance, and had less social support as compared with those in the high acculturation group; they also exhibited less disease activity as determined by the overall physician and patient global assessments of the Systemic Lupus Activity Measure. Abnormal illness-related behaviors and helplessness were not increased in the low acculturation group. Conclusions Low levels of acculturation were associated with indicators of low socioeconomic status, but also with less disease activity at enrollment into LUMINA; they were, however, not associated with more abnormal illness-related behaviors or with helplessness, as measured in this study. The possible impact of acculturation and of its mediators in the course and outcome of SLE among Hispanic patients needs to be determined longitudinally.
Nucleon and delta masses in twisted mass chiral perturbation theory

We calculate the masses of the nucleons and deltas in twisted mass heavy baryon chiral perturbation theory. We work to quadratic order in a power counting scheme in which we treat the lattice spacing, $a$, and the quark masses, ${m}_{q}$, to be of the same order. We give expressions for the mass and the mass splitting of the nucleons and deltas both in and away from the isospin limit. We give an argument using the chiral Lagrangian treatment that, in the strong isospin limit, the nucleons remain degenerate and the delta multiplet breaks into two degenerate pairs to all orders in chiral perturbation theory. We show that the mass splitting between the degenerate pairs of the deltas first appears at quadratic order in the lattice spacing. We discuss the subtleties in the effective chiral theory that arise from the inclusion of isospin breaking.
Liquid ion exchange membranes of extreme ionic selectivity and high transmissivity.

Liquid, “oil,” membranes in electrolytic systems have been extensively studied, particularly their electromotive behaviour. Nernst and Riesenfeld [1] considered concentration cells, c1 A+L- | Membrane |c2 A+L-, in which the electrolyte concentrations within the membrane phase at the phase boundaries are c1 • k and c2 • k, where k is the distribution coefficient. The two phase boundary potentials are identical in magnitude and opposite in signs. Thus, the effective electromotive force of the cell is the diffusion potential c1 • k||c2 • k within the liquid membrane. The ionic selectivities of such membranes, the ratio of their transmissivities for the anions over that for cations or vice versa, are computed from the concentration potentials. The latter are ordinarily low because the mobilities of most ions differ only within a limited range; correspondingly, the ionic selectivities of such membranes are rather limited.
HIV-1 non-specifically stimulates production of transforming growth factor-β1 transfer in primary astrocytes

Abstract HIV-1 expression in monocytes/macrophages can be controlled by transforming growth factor-beta l (TGF-β1). TGF-β1 is present in astrocytes surrounding HIV-1-infected monocyte/macrophages in brain tissue from patients with AIDS but not from seronegative, normal individuals. We sought to determine whether or not production of TGF-β1 can be directly stimulated by HIV-1 in astrocytes. Astrocytes from neonatal rat cortex grown in primary culture were exposed to HIV-1 virions for 24 h. One day later, TGF-β1 was measured in culture supernatants by a biological assay. HIV-1 caused 1.7-2.1-fold increase in extracellular concentration of TGF-β1. TGF-β1 production also was stimulated by recombinant HIV-1 proteins gp120, p66 and p24. Gpl20 labeled with fluorescein was visualized inside astrocytes and its stimulatory effect was not blocked by antibodies against rat CD4. The effect was not specific to HIV-1 and its proteins, because non-opsonized Latex particles and leucine methyl ester (LME) (known to be phagocytosed and endocytosed, respectively, by astrocytes) also stimulated TGF-β1 production. The effect was inhibited by two inhibitors of the phago/endocytotic pathway, chloroquine and leupeptin. These results may be relevant to the neuropathogenesis of HIV-1 infection.
The structure and thermal properties of synthetic realgar (As4S4)

Abstract Thermal analysis and X-ray powder diffraction data have been used to show that realgar synthesized directly from arsenic and sulfur exists in the high temperature β phase, which is metastable at room temperature. The X-ray powder data indicated that the metastable β phase is orthorhombic with lattice constants a = 9·95 A , b = 13·49 A and c = 7·07 A . The enthalpy of the α to β transition and the enthalpy of fusion were measured as 0·83 kcal/mole and 6·0 kcal/mole respectively. The observed stability of β realgar relative to decomposition to As2S3 was greater than that reported in the literature for α realgar.
Effects of Chronic Nanoparticulate Silver Exposure to Adult and Juvenile Sheepshead Minnows (Cyprinodon variegatus)

The use of nanoparticulate silver (AgNP) is increasingly widespread and recently has been shown to have a plausible release route into aquatic environments. To date, relatively little research has examined the effects of AgNP on estuarine fish. The authors present data indicating that chronic exposure to low levels of AgNP induces significant adverse effects in both juvenile and adult sheepshead minnows (Cyprinodon variegarus; SHMs). Chronic exposure to low levels of AgNP produced significant increases in tissue burdens in both juvenile and adult SHMs, resulting in significant thickening of epithelia gill tissue and in dramatically altered gene expression profiles. The results do not appear to be attributable to the release of silver ions through particle dissolution. The alteration in gene expression was greatest in adult gonads, but no evidence of AgNP-related dysfunction was found at the tissue level. In contrast, the authors found a significant effect on gill morphology, but very little evidence of effect on gill transcription profiles. Environ. Toxicol. Chem. 2012;31:160–167. © 2011 SETAC
Controlled radical polymerization

Fundamentals of controlled/“living” radical polymerization are given together with a discussion of selected initiating/catalytic systems which provide structural, compositional, and functionality control during radical polymerization. Four systems which enable the synthesis of polymers with low polydispersities (Mw/Mn 10 000), and high degrees of functionality are: nitroxide-mediated polymerization of styrene and styrene copolymers; organometallic compounds used for polymerization of acrylates; atom transfer radical polymerization of various monomers; and the degenerative transfer process. Also important in this field are new structural features and potential applications of controlled radical polymerization.
4552 Non contrast helical computed tomography versus endosonography for suspected choledocholithiasis and common bile duct dilation: a prospective comparative study.

Background: Since Biliary gallstone disease is common in the U.S. population, various imaging modalities are utilized preoperatively for establishing the diagnosis as well as localizing gallstones in the biliary system.Some previous data suggest that a thin cut unenhanced HCT provides improved imaging of the common bile duct.EUS has been shown to have a high sensitivity and specificity for CBD stone.To date,there has been no direct comparison between Endoscopic Ultrasound and non-contrast HCT in evaluating the gall bladder disease. Aim:To prospectively compare thin cut non-contrast HCT and EUS for evaluating patients with suspected biliary disease(ie;common bile duct dilation and choledocholithiasis). Methods:Fifteen subjects were evaluated for EUS for suspected biliary disease.Fourteen of the subjects were confirmed with EUS to have CBD stone.All patients underwent 3mm cuts non-contrast HCT within 72 hours of Endoscopic Ultrasound(EUS). Using EUS as the gold standard,the sensitivity,specificity,and accuracy for dectecting CBD stones and bile duct dilation were calculated for patients in the HCT group. Results: When comparing CBD stone and bile duct dilation to the gold standard EUS,the accuracy for detecting CBD stone in the HCT group was 21%(3/14 paitients),and the sensitivity and specificity were 57% and 36% respectively.However,the accuracy of identifying ductal dilation on noncontrast HCT was 50%,and the sensitivity and specificity were 64% and 36% respectively. Conclusion: Endoscopic Ultrasound appears to be a superior imaging modality for detecting CBD stones and ductal dilation compared to non-contrast HCT.Although both methods(EUS and HCT) appear to be relatively safe and comaparable in cost,EUS seems to be a preferred means of evaluating the diseases associated with the biliary system. This is an ongoing study,and in future, a larger sample will help delinate the best diagostic modality for evaluating biliary disease.
Incidence-based cost estimates require population-based incidence data. A critique of Mahan et al.

Incidence-based cost estimates require population-based incidence data. A critique of Mahan et al. -
Approaches to Solving Health Disparities Panel Reflections

The articles on approaches to solving health disparities1–4 in this supplement to Pediatrics address 2 overarching themes: 1. The paucity of research on interventions to reduce child disparities: Most intervention research has focused on adults, and most medical or clinical care research has focused on general quality improvement rather than disparities. 2. The need to directly or indirectly address disparities in health status and in health care. Addressing health care disparities will not eliminate health-status disparities, but failure to address health care disparities could worsen health-status disparities. Addressing disparities in health care is, in part, about equity goals, but it is also about accountability in the health system. Third-party payers in the public and private sectors expect that people with similar needs will receive similar treatment. This is a matter of basic fairness. The articles point out that disparities related to race/ethnicity, socioeconomic status, generation, and geography are closely intertwined. Disentangling this web could be useful for developing more tailored interventions, but it is not critical for making progress in reducing racial disparities. For example, Ochoa and Nash3 discuss … Address correspondence to Marsha Lillie-Blanton, DrPH, George Washington University School of Public Health and Health Services, Department of Health Policy, Ross Hall, Washington, DC 20010. E-mail: lblanton{at}gwu.edu
Free and constrained concept learning and subsequent recall

Four different arrays of materials ranging from high-frequency words to random patterns were presented to two groups of Ss. A “free” group was required to impose their own categorization on the 52 stimulus instances and to show consistency in their sorting behavior; a “constrained” group, yoked with the free group, learned the concepts used by the free Ss as target concepts. The free Ss attained criterion significantly faster, with fewer errors and less time per trial, than the constrained Ss. Nearly half of the free Ss imposed a consistent categorization before they had seen all the instances. Free Ss used about four categories regardless of stimulus complexity. Recall of high-frequency words was a linear function of the number of categories used.
Application-Level Scheduling on Distributed Heterogeneous Networks

Heterogeneous networks are increasingly being used as platforms for resource-intensive distributed parallel applications. A critical contributor to the performance of such applications is the scheduling of constituent application tasks on the network. Since often the distributed resources cannot be brought under the control of a single global scheduler, the application must be scheduled by the user. To obtain the best performance, the user must take into account both application-specific and dynamic system information in developing a schedule which meets his or her performance criteria. In this paper, we define a set of principles underlying application-level scheduling and describe our work-in-progress building AppLeS (application-level scheduling) agents. We illustrate the application-level scheduling approach with a detailed description and results for a distributed 2D Jacobi application on two production heterogeneous platforms.
On the dipole moment of three identical spherical atoms

Martin's perturbation theory result [2] for the dipole moment of three identical spherical atoms at large separations is shown to simplify: There are two contributions to this three-atom dipole and the strength of each factors into a product of the dipole polarizability of one atom and a two-atom average of dipole and quadrupole matrix elements. The simplified results are used to obtain an improved evaluation of the three-atom dipole of three He atoms, employing extensive pseudo-spectral representations of the dipole and quadrupole excitations.
Association between cancer prevalence and use of thiazolidinediones: results from the Vermont Diabetes Information System.

Peroxisome proliferator-activated receptors (PPARs) have emerged as important drug targets for diabetes. Drugs that activate PPARγ, such as the thiazolidinediones (TZDs), are widely used for treatment of Type 2 diabetes mellitus. PPARγ signaling could also play an anti-neoplastic role in several in vitro models, although conflicting results are reported from in vivo models. The effects of TZDs on cancer risk in humans needs to be resolved as these drugs are prescribed for long periods of time in patients with diabetes. A total of 1003 subjects in community practice settings were interviewed at home at the time of enrolment into the Vermont Diabetes Information System, a clinical decision support program. Patients self-reported their personal and clinical characteristics, including any history of malignancy. Laboratory data were obtained directly from the clinical laboratory and current medications were obtained by direct observation of medication containers. We performed a cross-sectional analysis of the interviewed subjects to assess a possible association between cancer diagnosis and the use of TZDs. In a multivariate logistic regression model, a diagnosis of cancer was significantly associated with TZD use, even after correcting for potential confounders including other oral anti-diabetic agents (sulfonylureas and biguanides), age, glycosylated hemoglobin A1C, body mass index, cigarette smoking, high comorbidity, and number of prescription medications (odds ratio = 1.59, P = 0.04). This association was particularly strong among patients using rosiglitazone (OR = 1.89, P = 0.02), and among women (OR = 2.07, P = 0.01). These data suggest an association between TZD use and cancer in patients with diabetes. Further studies are required to determine if this association is causal.
Normative Legitimacy: Rules of Appropriateness in Citizens’ Assessments of Individual Judicial Decisions

This study investigates the interaction between rules of appropriateness, popular support for judicial decisions, and policy preferences in assessments of the legitimacy of court decisions. We conduct two 3 × 2 × 2 experiments examining participants’ perceptions of legitimacy in cases involving the tort liability of gun manufacturers (Experiment 1) and same-sex marriage (Experiment 2). By manipulating the explanation for the judge's decision (bribe, political contribution, ideology, and law), we examine how participants assess the legitimacy of motivations suggesting compliance with, and deviations from, rules of appropriate judicial behavior in relation to one another. We also analyze how such rules interact with other factors theorized to influence assessments of legitimacy. Our findings demonstrate that rules of appropriateness matter most in participants’ assessments of the legitimacy of court decisions. Moreover, as hypothesized, the influence of other variables is conditioned on compliance with deci...
Modeling the rally event in presidential politics: Toward conceptual and methodological clarity

Abstract This research provides conceptual clarity both to the modeling of rally events in presidential politics by introducing the stimulus-cognitive response model and to the measurement of rally events by presenting the steps necessary for proper specification and empirical analysis using the time-series method. The utility of stimulus-cognitive response modeling in conjunction with time-series is demonstrated by an examination of the attempted assassination of President Ronald Reagan. Several of the specific findings are counterintuitive and have implications for the presidency-congress literature.
SYNTHESES OF FERROCENYLFLUOROPHOSPHINIC ACID AND RELATED COMPOUNDS1

Abstract Ferrocenylfluorophosphinic acid (η5-C5H5)Fe(η5-C5H4POH(O)F), ferrocenyldifluorophosphine oxide (η5-C5H5)Fe(η5-C5H4POF2) and ferrocenyltetrafluorophosphorane (η5-C5H5)Fe(η5-C5H4PF4) are prepared from the reaction of ferrocene with PF5 in CH2Cl2 and are characterized by proton, carbon, fluorine and phosphorus resonance spectra.
Multiple forms of serum cholinesterase

Abstract Two additional molecular forms of serum cholinesterase have been demonstrated in one of two purified enzyme sources. The other preparation revealed five components and occasionally revealed the extra bands. All components were converted to one major form by concentration. All forms hydrolyzed four substrates by the zymogram technique. Each molecular component was completely susceptible to eserine (10 −5 m ) inhibition by spectrophotometric assay. The determination of inhibitor susceptibility in starch gels revealed partial susceptibility of the major form to eserine. A hypothesis was presented that described the multiple components of serum cholinesterase as a series of polymers and/or conformational isomers. The evidence indicated that the multiple forms of serum cholinesterase were isozymes as demonstrated by their source (serum or plasma), similar substrate specificity, complete susceptibility to eserine, and interconvertibility.
Degradation of perfluoropolyether lubricants on magnetic recording disks during sliding

AbstractDegradation of perfluoropolyether lubricants (Fomblin Z-Dol and Fomblin AM 2001) on the magnetic recording thin-films disks are studied during sliding with an Al2O3-TiC slider under high vacuum. Gaseous products generated from the head/disk interfaces are detected and monitored as a function of sliding distance using a quadrupole mass spectrometer. Effects of overcoats and surface roughnesses of disks on degradation of lubricants and coefficient of friction were also studied. Experimental results show that the gaseous products generated from Z-Dol and AM 2001 lubricants during sliding are quite similar. Degradation of both lubricants is found to take place from the beginning of sliding, and the evolution rate of decomposition fragments decreases with the sliding distance. Removal of the lubricants is accompanied by a rapid rise in the coefficient of friction of the interfaces, followed by gaseous products from the tribochemical reaction of the overcoat material. Surface roughness of the disk has a...
Energy and civilization

Abstract Dr. Dixy Lee Ray is a distinguished scientist with a long and outstanding career. She was successively a Commissioner and Chairman of the U.S. Atomic Energy Commission. Later on, she served as the Assistant Secretary of State responsible for international aspects of oceans and environment and was elected Governor of the State of Washington. Dr. Ray's career has included the promotion of energy and the protection of the environment. In her entire career she has insisted that scientific facts must be used as the basis for decision making whenever applicable. Dr. Ray was the keynote speaker during the workshop dealing with waste containing alpha emitting radionuclides held in Gaithersburg, Maryland, in August of 1982. Her extemporaneous presentation was later on transcribed and edited. Following is an excerpt of her talk.
Dynamics and anisotropy of the Earth's inner core

Macroscopic processes which may be responsible for the anisotropic structure in the Earth's inner core are examined. It is concluded that the magnetic interaction with the outer core plays the most important role in the dynamics of the inner core. Deformation due to the magnetic interaction causes cumulative strain at least for a period of one magnetic polarity (-0.1-10my), and can result in a large strain (-1-103) leading to the formation of anisotropic structures. The flow caused by the magnetic field results in continuing melting and solidification at the inner-outer core boundary which gives rise to a large energy release (or absorption). The present model shows that the pattern of energy release (or absorption) due to this mechanism is consistent with that of dynamo models, indicating that the energy release (or absorption) caused by this mechanism enhances convection in the outer core and hence stabilizes the magnetic field which is otherwise highly unstable.
Canine Morphology: Hunting for Genes and Tracking Mutations

In this essay, Abigail Shearin and Elaine Ostrander discuss the proposed genomic mechanisms for the extraordinary level of phenotypic variation observed in the domestic dog and the evidence detailing the variants responsible for the many shapes, sizes, textures, and colors of man's best friend.
Sexual revictimization among sexual minorities: A preliminary study

The present study examined patterns of sexual assault and its psychological correlates among gay men, lesbians, and bisexual men and women (GLB). A community sample of 342 GLB individuals completed questionnaires assessing victimization history and psychological functioning. Nearly 63% of participants reported some form of sexual assault, and nearly 40% reported sexual revictimization, defined as contact or penetrative sexual assault reported in both childhood and adulthood. Gay men and bisexual men and women were more likely to report sexual revictimization than lesbians. Sexual victimization was associated with greater psychological distress, with sexually revictimized individuals reporting the highest levels of psychological symptomatology. The implications of these findings are discussed, and suggestions for future directions are offered.
Direct Recordings from the Auditory Cortex in a Cochlear Implant User

Electrical stimulation of the auditory nerve with a cochlear implant (CI) is the method of choice for treatment of severe-to-profound hearing loss. Understanding how the human auditory cortex responds to CI stimulation is important for advances in stimulation paradigms and rehabilitation strategies. In this study, auditory cortical responses to CI stimulation were recorded intracranially in a neurosurgical patient to examine directly the functional organization of the auditory cortex and compare the findings with those obtained in normal-hearing subjects. The subject was a bilateral CI user with a 20-year history of deafness and refractory epilepsy. As part of the epilepsy treatment, a subdural grid electrode was implanted over the left temporal lobe. Pure tones, click trains, sinusoidal amplitude-modulated noise, and speech were presented via the auxiliary input of the right CI speech processor. Additional experiments were conducted with bilateral CI stimulation. Auditory event-related changes in cortical activity, characterized by the averaged evoked potential and event-related band power, were localized to posterolateral superior temporal gyrus. Responses were stable across recording sessions and were abolished under general anesthesia. Response latency decreased and magnitude increased with increasing stimulus level. More apical intracochlear stimulation yielded the largest responses. Cortical evoked potentials were phase-locked to the temporal modulations of periodic stimuli and speech utterances. Bilateral electrical stimulation resulted in minimal artifact contamination. This study demonstrates the feasibility of intracranial electrophysiological recordings of responses to CI stimulation in a human subject, shows that cortical response properties may be similar to those obtained in normal-hearing individuals, and provides a basis for future comparisons with extracranial recordings.
A genome-wide affected sibpair linkage analysis of hypertension: the HyperGEN network

Results are reported here from a genome-wide linkage analysis of hypertension in a large sample of hypertensive (affected) sibpairs (650 African American and 915 white sibpairs) recruited by the HyperGEN Network of the National Heart, Lung and Blood Institute (NHLBI) Family Blood Pressure Program (FBPP). Analysis using MAPMAKER/SIBS suggests one interesting region with a LOD score of 2.08 at 63 cM from the p telomere on chromosome 2 in the African American sibpairs, which may harbor hypertension susceptibility genes.
Patterns of 3,3′,5′-Triiodothyronine Monodeiodination in Hypothyroidism and Nonthyroid Illnesses*

Available evidence suggests that outer ring monodeiodination of T4 is reduced in nonthyroidal illnesses (NTI), whereas it is normal or increased in hypothyroid patients. To determine whether a similar abnormality also occurs in rT3 metabolism, we have studied serum concentration of 3,3′-diiodothyronine (T2) after oral administration of 300 µg rT3 to 13 normal, 7 hypothyroid, and 12 NTI individuals. Also, we studied serum concentrations of 3′,5′-T2 after rT3 administration in order to examine the effect of hypothyroidism and NTI on inner ring monodeiodination of rT3. The mean increments above baseline serum concentrations of rT3 and 3′,5′-T2 did not differ significantly in normal, NTI, and hypothyroid groups at anytime during 4 h after rT3 administration. However, increments above baseline serum 3,3′-T2 concentrations 1 and 2 h after rT3 administration were significantly lower (P < 0.05) in the NTI group (mean ± SE, 0.7 and 0.9 ± 0.7 ng/dl, respectively) than in the normal group (2.7 ± 0.7 and 3.8 ± 0.9 ng...
Studies of Jet Fuel Thermal Stability in a Flowing System

A flowing, single-pass heat exchanger test rig, with a fuel capacity of 189 liters, has been developed to evaluate jet fuel thermal stability. This “Phoenix Rig” is capable of supplying jet fuel to a 2.15 mm i.d. tube at a pressure up to 3.45 MPa, fuel temperature up to 900 K, and a fuel-tube Reynolds number in the range 300–11,000. Using this test rig, fuel thermal stability (carbon deposition rate), dissolved oxygen consumption, and methane production were measured for three baseline jet fuels and three fuels blended with additives. Such measurement were performed under oxygen-saturation or oxygen-starved conditions. Tests with all of the blended fuel samples showed a noticeable improvement in fuel thermal stability. Both block temperature and test duration increased the total carbon deposits in a nonlinear fashion. Interestingly, those fuels that need a higher threshold temperature to force the consumption of oxygen exhibited greater carbon deposits than those that consume oxygen at a lower temperature. These observations suggested a complicated relationship between the formation of carbon deposits and the temperature-driven consumption of oxygen. A simple analysis, based on a bimolecular reaction rate, correctly accounted for the shape of the oxygen consumption curve for various fuels. This analysis yielded estimates of global bulk parameters of oxygen consumption. The test rig yielded quantitative results, which will be very useful in evaluating fuels additives, understanding the chemistry of deposit formation, and eventually developing a global chemistry model.
Social serendipity: mobilizing social software

Many mobile devices incorporate low-power wireless connectivity protocols, such as Bluetooth, that can be used to identify an individual to other people nearby. We have developed an architecture that leverages this functionality in mobile phones - originally designed for communication at a distance - to connect people across the room. Serendipity is an application of the architecture. It combines the existing communications infrastructure with online introduction systems' functionality to facilitate interactions between physically proximate people through a centralized server. A new mobile-phone-based system uses Bluetooth hardware addresses and a database of user profiles to cue informal, face-to-face interactions between nearby users who don't know each other, but probably should.
Learning Disabilities Occurring Concomitantly with Linguistic Differences

This article discusses characteristics of educational environments that facilitate success for culturally and linguistically diverse (CLD) learners, thereby reducing inappropriate referrals to special education, and offers recommendations for adapting referral and assessment processes to better serve CLD students suspected of having learning disabilities. Effective instructional practices are considered, and competencies needed by teachers who serve CLD students with learning disabilities are suggested. Specific attention is given to identifying and serving students with learning disabilities who are also limited English proficient.
Kinetic evaluation of the propranolol-quinidine combination.

The kinetics of quinidine and propranolol, administered singly and in combination, were evaluated in 5 healthy subjects. The orally administered doses resulted in plasma concentrations within the therapeutic range. For each drug the average steady-slate plasma concentration, maximal plasma concentration, and time of maximum plasma concentration were not altered by the presence of the other drug. This study shows no kinetic interaction between quinidine and propranolol in normal subjects. Clinical Pharmacology and Therapeutics (1980) 27, 450–453; doi:10.1038/clpt.1980.62
Segmentation of rat brain MR images using a hybrid fuzzy system

We have developed a magnetic resonance (MR) image segmentation system which consists of a fuzzy ruled-based system and a fuzzy c-means algorithm (FCM). The first stage of the system is the fuzzy ruled-based system which classifies most pixels of MR images into several known classes and one "unclassified" class. In the second stage, the classified result of the first stage is used to find the initial prototypes for FCM and the "unclassified" pixels are classified by FCM. The result of this combination is a very robust classification system. Rat brain MR images with stroke lesions are segmented. This system successfully identified the penumbra area of the rat brain. >
Altered erythrocyte membrane phosphorylation in psoriasis.

SUMMARY Autophosphorylation by [y-32P]ATP of erythrocyte membranes from controls, psoriatic patients and patients with skin disorders other than psoriasis was compared by polyacrylamide gel electrophoresis. Compared with controls, membranes from psoriatic patients showed significantly less 32P incorporation in the band 2 region (nomenclature of Fairbanks et al., 1971). In addition, psoriasis and some of the other skin diseases examined displayed decreased phosphorylation in the region of bands 2.9-3 and 4.5-4.8. A new polypeptidc band in the 18-20,000 dalton region was also observed in the diseases examined. Altered epidermal plasma membranes have been implicated in the pathogenesis of psoriasis, and our findings suggest the defective plasma membranes may be a generalized phenomenon in this disorder. Mahrle & Orfanos (1977) have suggested that psoriasis may be a result of alteration or failure in control mechanisms pertaining to the epidermal plasma membrane system. Evidence in support of this hypothesis comes from observations of functional deficiency in some of the plasma membrane-associated enzymes and other components of skin. The most readily recognized alterations are in connection with the adenosine 3′,5′-cyclic monophosphate (cyclic AMP) and guanosine 3′,5′-cyclic monophosphate (cyclic GMP) balance (Voorhees & Duell, 1975). Although cyclic AMP levels are not altered in psoriatic skin (Adachi ei al., 1981,1980; Marcelo, et al., 1979), adenylate cyclase is modified in terms of its response to epinephrine, prostaglandin E, histamine, AMP, adenosine and sodium fluoride (Wright et al., 1973; lizuka et al., 1978), whereas the cyclic GMP level is increased (Adachi et al., 1981, 1980; Marcelo et al., 1979). Cytochemical methods have revealed a decrease in membrane-bound ATPase and phosphomonoesterase activities in psoriatic epidermis (Mahrle & Orfanos, 1975) and notable changes in the distribution of compartmcntation of membrane-bound glycoconjugates (Orfanos, Mahrle 6k Runne, 1976). Recently, an increased uptake of radioactively labelled sugars into the
Anamnestic Recall of Stroke Related Deficits – An Animal Model

Background and Purpose— Anamnestic recall of stroke-related deficits is a common clinical observation, especially during periods of systemic infection. The pathophysiology of this transient re-emergence of neurological dysfunction is unknown. Methods— Male Lewis rats underwent 3 hours middle cerebral artery occlusion and were treated with lipopolysaccharide or saline at the time of reperfusion. The delayed-type hypersensitivity (DTH) response to myelin basic protein was examined 28 days after middle cerebral artery occlusion. Changes in behavioral outcomes were assessed after DTH testing and repeat administration of lipopolysaccharide or saline at 34 days. At the time of euthanasia (36 days), the immunologic response of splenocytes to myelin basic protein, neuron-specific enolase, and proteolipid protein was determined by enzyme-linked immunospot assay and the number of lymphocytes in the brain determined by immunocytochemistry. Results— Animals treated with lipopolysaccharide at middle cerebral artery occlusion had a greater DTH response to myelin basic protein than animals treated with saline. Among those animals that had fully recovered on a given behavioral test before DTH testing, those treated with lipopolysaccharide at middle cerebral artery occlusion displayed more neurological deterioration after DTH testing and had more CD8+ lymphocytes within the ischemic core of the brain. Furthermore, the Th1 immune response to brain antigens in the spleen was more robust among those animals that deteriorated after DTH testing and there were more CD4+ lymphocytes in the penumbral region of animals with a Th1 response to myelin basic protein. Conclusions— Our data suggest that an immune response to the brain contributes to the phenomenon of anamnestic recall of stroke-related deficits after an infection. The contribution of the immune response to this phenomenon deserves further investigation.
In vivo imaging of synapse formation on a growing dendritic arbor

The form of a neuron's dendritic arbor determines the set of axons with which it may form synaptic contacts, thus establishing connectivity within neural circuits. However, the dynamic relationship between dendrite growth and synaptogenesis is not well understood. To observe both processes simultaneously, we performed long-term imaging of non-spiny dendritic arbors expressing a fluorescent postsynaptic marker protein as they arborized within the optic tectum of live zebrafish larvae. Our results indicate that almost all synapses form initially on newly extended dendritic filopodia. A fraction of these nascent synapses are maintained, which in turn stabilizes the subset of filopodia on which they form. Stabilized filopodia mature into dendritic branches, and successive iterations of this process result in growth and branching of the arbor. These findings support a 'synaptotropic model' in which synapse formation can direct dendrite arborization.
Modeling the development of the component surface fractions of polycrystalline metals during ion implantation

Abstract Ion beam bombardment of metallic materials has become an accepted technique for the modification of the surface for the enhancement of particular properties. Recent literature on sputtering and materials modification reports little on the manner in which the surface develops or on the relationship of factors controlling the surface development and the end surface configuration. This paper attempts to establish a logical relationship between four of these factors and the surface configuration that evolves during the sputtering process. The four factors considered include the atomic density, the nuclear stopping power, the surface binding energy, and low energy channeling effects. A computer simulation of the implantation process was developed using these factors to modify the amorphous sputtering yields. Modified diffusion factors were applied for internal transport of atoms to the surface region. Results from the simulation have been compared with reported experiments and the predictions of the model compare favorably with the experimental results.
Background subtraction in highly dynamic scenes

A new algorithm is proposed for background subtraction in highly dynamic scenes. Background subtraction is equated to the dual problem of saliency detection: background points are those considered not salient by suitable comparison of object and background appearance and dynamics. Drawing inspiration from biological vision, saliency is defined locally, using center-surround computations that measure local feature contrast. A discriminant formulation is adopted, where the saliency of a location is the discriminant power of a set of features with respect to the binary classification problem which opposes center to surround. To account for both motion and appearance, and achieve robustness to highly dynamic backgrounds, these features are spatiotemporal patches, which are modeled as dynamic textures. The resulting background subtraction algorithm is fully unsupervised, requires no training stage to learn background parameters, and depends only on the relative disparity of motion between the center and surround regions. This makes it insensitive to camera motion. The algorithm is tested on challenging video sequences, and shown to outperform various state-of-the-art techniques for background subtraction.
Experimental observation and computational simulation of dynamic void collapse in single crystal cooper

Hollow circular cylinders of single crystal copper are subjected to externally applied explosive loads that cause the collapse of the cylinder. Then numerical simulations are performed to understand the deformation process that leads to localized deformation and tensile cracking, observed in partially collapsed cylinders of fcc single crystals. The results of experiments and numerical simulations are in good agreement.