cssi/SciSciGPT-SciSciNet huggingface dataset:
Genetic studies of complex human diseases: Characterizing SNP-disease associations using Bayesian networks

Background: Detecting epistatic interactions plays a significant role in improving pathogenesis, prevention, diagnosis, and treatment of complex human diseases. Applying machine learning or statistical methods to epistatic interaction detection will encounter some common problems, e.g., very limited number of samples, an extremely high search space, a large number of false positives, and ways to measure the association between disease markers and the phenotype. Results: To address the problems of computational methods in epistatic interaction detection, we propose a score-based Bayesian network structure learning method, EpiBN, to detect epistatic interactions. We apply the proposed method to both simulated datasets and three real disease datasets. Experimental results on simulation data show that our method outperforms some other commonly-used methods in terms of power and sampleefficiency, and is especially suitable for detecting epistatic interactions with weak or no marginal effects. Furthermore, our method is scalable to real disease data. Conclusions: We propose a Bayesian network-based method, EpiBN, to detect epistatic interactions. In EpiBN, we develop a new scoring function, which can reflect higher-order epistatic interactions by estimating the model complexity from data, and apply a fast Branch-and-Bound algorithm to learn the structure of a two-layer Bayesian network containing only one target node. To make our method scalable to real data, we propose the use of a Markov chain Monte Carlo (MCMC) method to perform the screening process. Applications of the proposed method to some real GWAS (genome-wide association studies) datasets may provide helpful insights into understanding the genetic basis of Age-related Macular Degeneration, late-onset Alzheimer’s disease, and autism.
Defective gamma-interferon production in peripheral blood leukocytes of patients with acute tuberculosis

Production of interferon (IFN)-gamma by peripheral blood leukocytes (PBL) was examined in cultures of unseparated fresh whole blood exposed to phytohemagglutinin (PHA), concanavalin A (Con A), or pokeweed mitogen (PWM). The yield of IFN-gamma was measured by a newly developed immunoradiometric assay. Nine of 14 patients with acute pulmonary tuberculosis (TB) showed a depressed IFN-gamma response to Con A and/or PWM. Only four of these TB patients also showed a depressed IFN-gamma response to PHA. Stimulation of the patients' PBL cultures with PHA in the presence of exogenous interleukin 2 (IL 2) produced normal IFN-gamma yields in all but the most severely depressed patients. PBL cultures of TB patients with defective IFN-gamma production in response to mitogenic lectins also produced less IFN-gamma after stimulation with tuberculin PPD. Although some patients showed a moderate degree of lymphopenia, their OKT4/T8 lymphocyte ratios were mostly normal or close to normal, with the notable exception of one TB patient who has been diagnosed to have the acquired immune deficiency syndrome (AIDS).
Spinal Activation of the cAMP-PKA Pathway Induces Respiratory Motor Recovery Following High Cervical Spinal Cord Injury

The present study investigated the involvement of the adenosine 3'5'-cyclic monophosphate-dependent protein kinase A (cAMP-PKA) pathway in the activation of the crossed-phrenic pathways after left C2 spinal cord hemisection. Experiments were conducted on left C2 spinal cord hemisected, anesthetized, vagotomized, pancuronium paralyzed, and artificially ventilated male Sprague-Dawley rats. One week post-injury, the ipsilateral phrenic nerve exhibited no respiratory-related activity indicating a functionally complete hemisection. Intrathecal spinal cord administration of the cAMP analog, 8-Br-cAMP at the level of the phrenic nucleus resulted in an enhancement of contralateral phrenic nerve output and a restoration of respiratory-related activity in the phrenic nerve ipsilateral to the hemisection. Furthermore, pre-treatment with Rp-8-Br-cAMP, a PKA inhibitor, abolished the effects of 8-Br-cAMP. These results suggest that PKA activation is necessary for the cAMP-mediated respiratory recovery following high cervical spinal cord injury and that activation of intracellular signaling cascades may represent an important strategy for improving respiratory function after spinal cord injury.
Statistically representative three-dimensional microstructures based on orthogonal observation sections

Techniques are described that have been used to create a statistically representative three-dimensional model microstructure for input into computer simulations using the geometric and crystallographic observations from two orthogonal sections through an aluminum polycrystal. Orientation maps collected on the observation planes are used to characterize the sizes, shapes, and orientations of grains. Using a voxel-based tessellation technique, a microstructure is generated with grains whose size and shape are constructed to conform to those measured experimentally. Orientations are then overlaid on the grain structure such that distribution of grain orientations and the nearest-neighbor relationships, specified by the distribution of relative misorientations across grain boundaries, match the experimentally measured distributions. The techniques are applicable to polycrystalline materials with sufficiently compact grain shapes and can also be used to controllably generate a wide variety of hypothetical microstructures for initial states in computer simulations.
A rheological model for particulate ceramic slurries at low temperatures

Ceramic particulate reinforced metal- and ceramic-matrix composites are increasingly being used in a wide range of applications in the electronics packaging, automotive and aerospace industries. This article presents an empirical correlation for the viscosity of particulate ceramic slurries in terms of the viscosity of the suspension medium, [mu][sub o], volume fraction of the solids in the slurry, [phi], shear rate, [gamma], and slurry temperature, T[sub sl]. The correlation was obtained from extensive rheological characterization of silicon carbide (SiC) slurry formulations, and is based on physical consistency validations. The proposed rheological model is valid over the range of shear rates between 6 and 96 sec[sub [minus]1], solids loading up to approximately 70 percent, and slurry temperatures between 0 and 25 C. The model predictions are shown to be in good agreement with the experimental data.
An improved synthesis of NHS-MAG3 for conjugation and radiolabeling of biomolecules with 99m Tc at room temperature

The mercaptoacetyltriglycine (MAG3) chelator has been shown to stably complex technetium-99m (99mTc) for nuclear imaging and radiorhenium (186/188Re) for tumor radiation therapy studies. The bifunctional N-hydroxysuccinimidyl ester of MAG3 with S-acetyl protection (N-hydroxysuccinimidyl S-acetylmercaptoacetyltriglycinate (NHS-MAG3)) has been successfully used to covalently conjugate a MAG3 chelator to primary amine functionalized biomolecules. We describe herein a simplified synthesis of NHS-MAG3 that begins with the preparation of the N-hydroxysuccinimidyl ester of S-acetylmercaptoacetic acid (N-succinimidyl S-acetylmercaptoacetate (SATA)) from mercaptoacetic acid and is followed by the synthesis of S-acetylmercaptoacetyltriglycine from SATA, together requiring about 14 days. Finally, the synthesis of NHS-MAG3 from S-acetylmercaptoacetyltriglycine requires a further 5 days. We had earlier described a method for the preparation of MAG3-conjugated and 99mTc-radiolabeled biomolecules that required elevated temperatures during postconjugation purification. We now report a modified method for the preparation that is accomplished at room temperature and therefore applicable to temperature-sensitive biomolecules. The conjugation and radiolabeling of bovine serum albumin is used as an example. The conjugation and purification requires about 2–3 h and the radiolabeling and postlabeling purification requires about an additional 2 h.
Test-retest reliability and the minimal detectable change for achilles tendon length: a panoramic ultrasound assessment

The purpose of the present study was to examine test-retest reliability and minimal detectable change (MDC) values for Achilles tendon (AT) length determined using panoramic ultrasound (US) imaging. Seventeen men (age = 21.0 ± 2.3 y) visited the laboratory on two separate days, where AT length was examined along the mid-longitudinal axis of the right lower leg with a portable B-mode panoramic US device. These measures were found to have acceptable reliability with intra-class correlation coefficient (ICC) and standard error of measurement (SEM) values of 0.954 and 4.43 mm (SEM% of the mean = 2.37%), respectively. In addition, the MDC for the panoramic US assessment of AT length was 12.27 mm (MDC% of the mean = 6.57%). These findings suggest that panoramic US imaging is a reliable technique for detection of clinically relevant changes in AT length and may therefore be a practical and time-efficient clinical tool for future studies examining AT length in vivo.
Impact Resistance and Fracture Toughness of Vanadium-Based Microalloyed Forging Steel in the As-Forged and Q&T Conditions

Microalloyed (MA) steels are a family of steels which are becoming an increasingly important economic alternative to the traditional quenched and tempered (Q and T) steels. Impact resistance and fracture toughness of vanadium-based MA forging steel, which is the most commonly produced MA steel, are investigated in this study. To compare the behavior with the Q and T steel, both the as-forged and the Q and T conditions are evaluated. Experimental results from Charpy V-notch impact and fracture toughness (K{sub R}-curve and J{sub IC}) tests are presented and discussed. Correlations between fracture resistance properties based on several proposed equations in the literature are also examined.
Presence and location of adrenergic nerve endings in the dental pulps of mouse molars

In all, 30 adult (45-day-old) Swiss Webster mice were used for light and electron microscopic examination of the presence, number, and location of adrenergic endings in the first molar teeth. Prior to sacrifice, 10 animals received i.p. injections at 8, 6, 4, and 2 hours of 0.5 cc of 20 mg/kg solution of 5-hydroxydopamine (5-OH-DA) as a label for adrenergic endings. The animals were then anesthetized, perfused with Karnovsky's fixative, and the teeth were postfixed in Osmic acid, decalcified, embedded in methacrylate, and serial-sectioned. The sections were surveyed by light microscopy, and the number and location of nerve endings containing the reduced 5-OH-DA were recorded. Ten control mice were injected with the vehicle solution and prepared in the same manner. A third series of mice were given a single injection of 5-OH-DA, sacrificed, and prepared for ultrastructural study. The molar pulps were divided into four areas to facilitate examination: pulp horns, coronal pulp, bifurcation area, and root pulp. These four areas were further divided into three zones: odontogenic, vascular-related, and nonvascular-associated. The location and number of endings were evaluated, and an average of approximately 70 endings containing the 5-OH-DA were found in each tooth using light microscopy. These represented 35.5 +/- 5.2 in the pulp horns; 26.1 +/- 2.4 in the central coronal; 5.4 +/- 0.7 in the bifurcation, and 5.6 +/- 0.9 in the root pulp per tooth. Vascular related endings were found in greatest number, the odontogenic zone next, and free endings lease. Verification of location of 5-OH-DA by ultrastructural analysis revealed the false transmitter in vesiculated endings in the four areas and zones of the pulp.
Nonperturbative Length Scale in High Temperature {QCD}

The string tension of spacelike Wilson loops is computed in SU(3) lattice gauge theory in the high-temperature deconfined phase. Its physical value is extracted following the continuum limit. An upper bound for the length scale where nonperturbative fluctuations become dominant is computed. The value of the string tension and the nonperturbative length scale are very close to their zero-temperature counterparts.
Tempo and Mode of Evolutionary Radiation in Iguanian Lizards

Identification of general properties of evolutionary radiations has been hindered by the lack of a general statistical and phylogenetic approach applicable across diverse taxa. We present a comparative analytical framework for examining phylogenetic patterns of diversification and morphological disparity with data from four iguanian-lizard taxa that exhibit substantially different patterns of evolution. Taxa whose diversification occurred disproportionately early in their evolutionary history partition more of their morphological disparity among, rather than within, subclades. This inverse relationship between timing of diversification and morphological disparity within subclades may be a general feature that transcends the historically contingent properties of different evolutionary radiations.
THE EFFECTS OF DIETARY α‐TOCOPHEROL AND SURFACE APPLICATION OF OLEORESIN ROSEMARY ON LIPID OXIDATION AND CHOLESTEROL OXIDE FORMATION IN COOKED RAINBOW TROUT (Oncorhynchus mykiss) MUSCLE

The inhibitory effect of dietary α-tocopherol supplementation (100 and 500 mg α-tocopheryl acetate/kg diet) and an oleoresin rosemary dip on lipid and cholesterol oxidation in cooked rainbow trout (Oncorhynchus mykiss) during storage at 4C for 48 h was investigated. The 2-thiobarbituric acid-reactive substances (TBARS) values of cooked fish muscle increased during storage for all treatments. Dietary α-tocopherol supplementation partially inhibited lipid oxidation. Surface application of oleoresin rosemary further enhanced this protective effect. Cholesterol oxides were formed in all the samples following cooking and storage. The major cholesterol oxidation products (COPS) were identified as 7 β-hydroxycholesterol, α- and β-epoxides, and 7-ketocholesterol. Formation of COPS was reduced by dietary supplementation with α-tocopherol and surface application of oleoresin rosemary. Statistical analysis revealed a highly significant (p < 0.01) inhibitory effect of oleoresin rosemary on COPS formation.
Graphical Approximation Model for Velocity Characteristics of Local Exhaust Inlets

The purpose of this study was to prepare a computer design model for approximating velocity characteristics of local exhaust inlets. The model provides approximate constant velocity contours for plain and flanged exhaust inlets having circular, rectangular and narrow slot end shapes. Configurations include single inlets, two identical inlets, a single inlet with a nearby boundary surface, and a single inlet in the presence of a crossdraft. The model is designed for use on a personal computer by individuals having a basic understanding of local exhaust inlet design. The model applies several major approximations to obtain mathematical representations of velocity contours and to utilize and expand the application of existing empirical data for centerline velocity gradients for different shapes of exhaust inlets. A graphical “contour displacement” method is used to minimize and hasten computations for user-specified velocity contours. The model also provides comparisons of the empirical results of different ...
Characteristics of participants in water exercise programs compared to patients seen in a rheumatic disease clinic.

Purpose. To determine if community-based water exercise programs are serving people with significant levels of disability and pain. Methods. Eighty-seven participants in water exercise classes and 174 patients from a rheumatic disease clinic were matched for age, sex, and diagnosis and comparisons were made between the groups for the study variables. Results. Patients had significantly higher disability, pain, global disease severity, anxiety, and depression and lower grip strength than participants. Osteoarthritis (OA) patients (n = 126) compared to OA participants (n = 63) had similar significant differences for all variables. Rheumatoid arthritis (RA) patients' (n = 48) scores were all more severe than RA participants' scores (n = 24), and these differences were similar in magnitude to OA differences, but only global disease severity and grip strength were statistically significantly different. Conclusions. Water exercise classes are reaching persons with important levels of dysfunction and pain, but more severely affected patients are underrepresented in such programs.
Double-spray counterflow diffusion flame model

In this spray model we consider two gaseous streams approaching each other from opposite directions in a counterflow. The two opposed streams each carry a distribution of liquid droplets. The sprays vaporize, and the vaporized fuel and oxidizer gases diffuse and convect toward a chemical reaction region near the stagnation plane, at which the reactants burn. A set of steady-state ordinary differential equations is derived to describe the temperature of the gas flow and the mass fractions of each reactant. We solve the differential equations in three consequent cases, each more complicated than the previous one: (i) fast vaporization and fast chemistry; (ii) finite-rate vaporization and fast chemistry; and (iii) finite-rate vaporization and finite-rate chemistry. Comparisons are made of our model results to previous fuel-spray-only and purely gaseous counterflow diffusion flame models. The parametric dependences of vaporization-zone movement, flame movement, temperature rise and degree of reactant leakage ...
Properties of Ascaris muscle mitochondria. I. Cytochromes

Abstract 1. The cytochrome system in Ascaris muscle mitochondria was further characterized using purer preparations. 2. Difference spectra (at 22 °C and −196 °C) of the mitochondrial preparations using succinate and ascorbate plus N , N , N ′, N ′-tetramethyl- p -phenylenediamine show that Ascaris muscle mitochondria contain cytochromes c 1 , c and aa 3 , and also at least three b -type cytochromes. The b -type cytochrome is the predominant component. 3. Cytochrome c and Ascaris cytochrome b -560 can be extracted from the mitochondrial preparations with 150 mM KCl, leaving the membrane-bound cytochromes c 1 , b and aa 3 in the KCl residue.
Dispositional, Ecological and Biological Influences on Adolescent Tranquilizer, Ritalin, and Narcotics Misuse.

Abstract The primary purpose of this study was to examine the extent to which two of the three sources of risk-taking—dispositional and ecological—in adolescence and demographic variables were related to Ritalin, tranquilizer and narcotics misuse. The secondary aim of this study was to distinguish subgroups of Ritalin, tranquilizer, and narcotics misusers using dispositional, ecological and demographic variables. An archival dataset containing 1672 participants (11–18 years old) was used. Ritalin, tranquilizer, and narcotics misuse were dichotomized and hierarchical logistic regressions were computed for dispositional and ecological sources of risk-taking and demographics. To distinguish subgroups of misusers, hierarchical multinomial regressions were computed. Dispositional, ecological, and demographic variables were related to Ritalin, tranquilizer, and narcotics misuse and distinguished among non-users, experimenters/occasional misusers, and frequent misusers. Prescription drug prevention programs should incorporate demographic, dispositional, and ecological variables and should parallel the guidelines currently used for developing effective substance abuse prevention programs.
On the scalability of IEEE 802.11 ad-hoc-mode timing synchronization function

The IEEE 802.11 standards support the peer-to-peer mode Independent Basic Service Set (IBSS), which is an ad hoc network with all its stations within each other's transmission range. In an IBSS, it is important that all stations are synchronized to a common clock. Synchronization is essential for the MAC layer power management. Also, if frequency hopping spread spectrum is used in the physical layer, synchronization is needed to ensure that all stations "hop" at the same time. This paper evaluates the synchronization mechanism as specified in the IEEE 802.11 standards. Through rigorous analysis, it is shown that when the number of stations in an IBSS is not very small, there is a non-negligible probability that stations may get out of synchronization. The more stations, the higher probability of asynchronism. In this sense, the current IEEE 802.11 synchronization algorithm does not scale; it cannot support a large-scale IBSS.To alleviate the asynchronism problem, this paper proposes a simple remedy to the 802.11 algorithm. The resulting algorithm enjoys many nice properties--it is compatible, scalable, effective, mobility-friendly and simple. We are able to exceed the industry expectation of time accuracy (maximum clock offset under 12 µs) without any change of beacon format.
G protein-coupled receptors in HIV and SIV entry: New perspectives on lentivirus–host interactions and on the utility of animal models

Entry of primate lentiviruses into target cells has recently been shown to depend upon the interaction of the viral envelope glycoprotein with CD4 and one or more members of the G protein-coupled receptor (GPCR) family of transmembrane proteins. In vivo, the transmission of HIV-1 infection generally requires viral strains that utilise chemokine recep- tor CCR5, and these strains prevail during the early course of infection. Strains isolated later, in the course of progression to immunodeficiency, are often CXCR4-tropic or are dual tropic for both chemokine receptors. SIV isolates also use CCR5 but are only rarely specific for CXCR4. Instead, SIVs use two orphan members of the GPCR family, named Bonzo/STRL33/TYMSTR and BOB/GPR15. Strains of HIV-2, which are closely related to the SIVs, also often utilise CXCR4, CCR5, BOB and/or Bonzo. Additional GPCR family members have also been shown to be utilised by various strains of HIV and SIV, albeit less efficiently and less frequently. Here we discuss the potential relationship between receptor specificity and viral pathogenesis as well as efforts to develop animal model systems to study the mechanism of disease progression.
Identification of genes that interact with the sina gene in Drosophila eye development.

Abstract The sina gene encodes a nuclear protein that is required for the correct development of R7 photoreceptor cells in the Drosophila eye. We conducted a genetic screen for mutations that reduce the activity of sina and found mutations that define nine genes whose products may be required for normal sina activity. Three of these genes also appear to be essential for signaling by the Sevenless-Ras pathway in R7 cells, of which one gene corresponds to the rolled locus (rl). The rl gene is known to encode a mitogen-activated protein kinase necessary for signaling by Ras. These results suggest that the products of these three genes may participate in a signaling pathway involving both Ras and Sina, possibly by functionally linking these two proteins.
An Investigation of Noise Amplitude Spectra Produced by a Direct-Current Plasma

Noise amplitude spectra for direct-current plasma atomic emission spectrometry (DCP-AES) were acquired. Flicker (1/f) noise dominates the signal at low frequencies, and white noise prevails at higher frequencies. Broad-band audio-frequency (af) noise was observed in the plasma continuum emission when the nebulizer gas was directed into the discharge. By increasing the electrode-gas flows, it was possible to narrow the frequency range and increase the amplitude of this af noise. The introduction of an easily ionized element into the plasma had little effect on the noise characteristics of the source.
Rethinking Al Qaeda: Leaderless jihad: terror networks in the twenty-first century

Leaderless jihad: terror networks in the twenty-first century, by Marc Sageman. Philadelphia: University of Pennsylvania Press, 2008, viii + 178 pp., notes to 184, bibliography to 191, index to 197...
Vertical forces induced in a 1/5 scale Mark I BWR toroidal wetwell under LOCA conditions

Abstract During a hypothetical loss-of-coolant-accident (LOCA) in a Mark I boiling water reactor (BWR) power plant, air, followed by steam, is injected into a toroidal wetwell about half-filled with water. Injection occurs below the water surface in a vertically downward direction through 0.6-m dia. open-end pipes called downcomers. A downward load is induced on the toroidal wetwell as the water that is initially inside the downcomers is forced into the water pool below them. The magnitude of this downward load increases for about 0.25 sec, until just after gas bubbles appear in the pool. The water surface inside the toroidal wetwell then moves rapidly upward, particularly in the region adjacent to the outside of the downcomers, as water is displaced by the gas bubbles. The gas bubbles over-expand, because the flow of gases from the downcomers is not sufficient to counteract the upward displacement of the water. The direction of net load on the toroidal wetwell now shifts upward and reaches a peak of approximately half the magnitude of the maximum downward load in about 0.5 sec. The vertical load then decreases in an oscillatory manner to static conditions in about 1 sec. We designed a 1/5-scale facility to experimentally verify the predicted loading function and to study the ensuing fluid dynamics phenomena. Analytical results were used to modify the design of the experimental apparatus so that the fluid-sturcture interaction in the toroidal wetwell did not adversely affect measurements. Using dimensional analysis, we developed scaling relationships that show the dimensionless grouping F pgL 3 and t 2 g L are invariant. Here, F is force, p is liquid density, g is the gravitational constant, L is length, and t is time. If water is used as the working fluid in the 1/5-scale experimental apparatus, the anticipated magnitude of forces would be 1/125 of that present in a full-scale BWR power plant and would occur in 1/√5 the time. For a structural analysis of the 1/5-scale facility, the toroidal wetwell, supports, and base structure were considered to be a spring-mass system excited by an appropriate loading function. The loading function was determined by use of the scaling relationships indicated and by anticipating full-scale BWR power plant forces. Frequency response of the toroidal wetwell was examined with finite-element computer techniques and also closed-form solutions. Required changes in the design of the experimental apparatus were incorporated so that load measurements accurately represented the loading function. Predicted vertical force-time signatures are presented.
Inhibition of a peripheral sympathetic-cholinergic system by presynaptic α2-adrenoceptors

Intravenous administration of catecholamines produced dose-related inhibition of electrodermal responses (EDRs) evoked by electrical stimulation of the post-ganglionic sciatic nerve in anaesthetized rats, with relative potencies being (−)-adrenaline > (±)-adrenaline > (−)-noradrenaline = (+)-adrenaline. The suppression of EDRs by (±)-adrenaline and (−)-noradrenaline was blocked by pretreatment with yohimbine (0.75 mg/kg i.v.) but not by prazosin (0.3 mg/kg i. v.). The selective α2-adrenoceptor agonist B-HT 920 also inhibited neurally evoked skin potential responses. This effect of B-HT 920 was antagonized by the selective α2-adrenoceptor antagonist idazoxan (0.1 mg/kg i. v.) but was insensitive to prazosin. Idazoxan was more potent than yohimbine in blocking (±)-adrenaline-induced suppression of EDRs. Methacholine administered into the femoral artery evoked EDRs by an atropine-sensitive mechanism. Methacholine-induced EDRs were not suppressed by intravenous administration of (−)-adrenaline (1 μg/kg or 3 μg/ kg) whereas EDRs evoked by the sciatic nerve stimulation on the other hindpaw were inhibited. Increase in the endogenous catecholamines by asphyxia strongly inhibited EDRs by a mechanism which was also sensitive to yohimbine but not to prazosin. These results suggest that peripheral presynaptic α2-adrenergic mechanisms are involved in inhibition of transmitter release in this sympatheticcholinergic system.
Bloom syndrome: an analysis of consanguineous families assigns the locus mutated to chromosome band 15q26.1

Abstract By the principle of identity by descent, parental consanguinity in individuals with rare recessively transmitted disorders dictates homozygosity not just at the mutated disease-associated locus but also at sequences that flank that locus closely. In 25 of 26 individuals with Bloom syndrome examined whose parents were related, a polymorphic tetranucleotide repeat in an intron of the protooncogene FES was homozygous, far more often than expected (P < 0.0001 by chi 2). Therefore, BLM, the gene that when mutated gives rise to Bloom syndrome, is tightly linked to FES, a gene whose chromosome position is known to be 15q26.1. This successful approach to the assignment of the Bloom syndrome locus to one short segment of the human genome simultaneously (i) demonstrates the power of homozygosity mapping and (ii) becomes the first step in a "reverse" genetics definition of the primary defect in Bloom syndrome.
From the library of record to the library as gateway: An analysis of three electronic table-of-contents services

It is widely recognized that a major transition is taking place in libraries, particularly in research libraries. The role and purpose of libraries is debated by policy makers and budget allocators. What exactly is the value of the library? How does the institution called “the library” serve its 1994 users? Some label the current situation one of “crisis,” while others believe it to be one of opportunity unparalleled in our history [l]. Four factors have come together in today’s environment to generate this crisis or opportunity for reexamination of the library. First, changes in the political climate of the United States have generated a new look at government services [2]. A combination of population, economic, and social factors have created a tight-budget situation within the public sector. As the budgetary pressure has increased, the role of government is being questioned. The issue of what services are essential has become a major topic of public policy debate. Funding for what are often considered nonessential services (education, libraries) as opposed to services considered essential (prisons, police, fire, garbage) has been increasingly questioned. However, it is not just the lack of financial resources that affects this conversation with political leaders, it is also accountability. Increasingly, legislators and board members are asking for a clear demonstration of the libraries’ value. What is it that libraries do that warrants such expenditures? What does a library contribute to the common good?
Potential of polycapillary optics for hard x-ray medical imaging applications

Polycapillary optics are shaped arrays of tiny hollow tubes through which x rays are guided by total external reflection at grazing incidence. In previous work, it has been demonstrated that a small prototype optic can provide nearly total scatter rejection at mammographic energies with simultaneous resolution enhancement due to geometrical-blur- free magnification. Recent measurements on straight capillaries and lenses show that capillary optics could possibly be applied to higher energy imaging applications, such as angiography and chest radiography. Transmission efficiency for straight bundles was measured to be fairly flat out to 60 keV and in excess of 30% at 80 keV. Extensive simulations and measurements have been performed for prototype capillary optics at photon energies from 20 to 100 keV. Transmission of the central part (0.5 mm diameter) of a 166 mm long prototype tapered lens was as high as 60% near 30 keV and in excess of 40% up to 70 keV. The reduction of transmission at high energies was found to be caused by optic profile defects: surface waviness and centerline bending. Absorption and scatter rejection measurements indicate that almost total scatter rejection is achievable at high energies. Scatter transmission of the tapered borosilicate glass lens is around 5% at 60 keV. Even better scatter rejection could be achieved by using lead glass capillaries. By estimating the contrast improvement factor and Signal to Noise Ratio (SNR) with the scaled up lenses, this paper demonstrates the potential for polycapillary optics in various medical x-ray imaging applications.
RNA polymerase III and RNA polymerase II promoter complexes are heterochromatin barriers in Saccharomyces cerevisiae

The chromosomes of eukaryotes are organized into structurally and functionally discrete domains. Several DNA elements have been identified that act to separate these chromatin domains. We report a detailed characterization of one of these elements, identifying it as a unique tRNA gene possessing the ability to block the spread of silent chromatin in Saccharomyces cerevisiae efficiently. Transcriptional potential of the tRNA gene is critical for barrier activity, as mutations in the tRNA promoter elements, or in extragenic loci that inhibit RNA polymerase III complex assembly, reduce barrier activity. Also, we have reconstituted the Drosophila gypsy element as a heterochromatin barrier in yeast, and have identified other yeast sequences, including the CHA1 upstream activating sequence, that function as barrier elements. Extragenic mutations in the acetyltransferase genes SAS2 and GCN5 also reduce tRNA barrier activity, and tethering of a GAL4/SAS2 fusion creates a robust barrier. We propose that silencing mediated by the Sir proteins competes with barrier element-associated chromatin remodeling activity.
Reverse engineering the lordosis behavior circuit

Reverse engineering takes the facts we know about a device or a process and reasons backwards to infer the principles underlying the structure-function relations. The goal of this review is to apply this approach to a well-studied hormone-controlled behavior, namely the reproductive stance of female rodents, lordosis. We first provide a brief overview on the considerable amount of progress in the analysis of female reproductive behavior. Then, we propose an analysis of the mechanisms of this behavior from a reverse-engineering perspective with the goal of generating novel hypotheses about the properties of the circuitry elements. In particular, the previously proposed neuronal circuit modules, feedback signals, and genomic mechanisms are considered to make predictions in this manner. The lordosis behavior itself appears to proceed ballistically once initiated, but negative and positive hormonal feedback relations are evident in its endocrine controls. Both rapid membrane-initiated and slow genomic hormone effects contribute to the behavior's control. We propose that the value of the reverse-engineering approach is based on its ability to provide testable, mechanistic hypotheses that do not emerge from either traditional evolutionary or simple reductionistic perspectives, and several are proposed in this review. These novel hypotheses may generalize to brain functions beyond female reproductive behavior. In this way, the reverse-engineering perspective can further develop our conceptual frameworks for behavioral and systems neuroscience.
Mothers' amygdala response to positive or negative infant affect is modulated by personal relevance.

Understanding, prioritizing and responding to infant affective cues is a key component of motherhood, with long-term implications for infant socio-emotional development. This important task includes identifying unique characteristics of one’s own infant, as they relate to differences in affect valence—happy or sad—while monitoring one’s own level of arousal. The amygdala has traditionally been understood to respond to affective valence; in the present study, we examined the potential effect of personal relevance on amygdala response, by testing whether mothers’ amygdala response to happy and sad infant face cues would be modulated by infant identity. We used functional MRI to measure amygdala activation in 39 first-time mothers, while they viewed happy, neutral and sad infant faces of both their own and a matched unknown infant. Emotional arousal to each face was rated using the Self Assessment Manikin Scales. Mixed-effects linear regression models were used to examine significant predictors of amygdala response. Overall, both arousal ratings and amygdala activation were greater when mothers viewed their own infant’s face compared with unknown infant faces. Sad faces were rated as more arousing than happy faces, regardless of infant identity. However, within the amygdala, a highly significant interaction effect was noted between infant identity and valence. For own-infant faces, amygdala activation was greater for happy than sad faces, whereas the opposite trend was seen for unknown-infant faces. Our findings suggest that the amygdala response to positive and negative valenced cues is modulated by personal relevance. Positive facial expressions from one’s own infant may play a particularly important role in eliciting maternal responses and strengthening the mother-infant bond.
A fast navigator-gated 3D sequence for delayed enhancement MRI of the myocardium: comparison with breathhold 2D imaging.

Purpose To develop a rapid navigator-gated three-dimensional (3DNAV) delayed-enhancement MRI (DE-MRI) sequence for myocardial viability assessment, and to evaluate its performance with breathhold two-dimensional (2DBH) DE-MRI sequence as the reference standard. Materials and Methods 2DBH DE-MRI was initiated 10 minutes after contrast administration and followed by 3DNAV DE-MRI in 23 patients at 1.5 T. Comparison was performed using three qualitative criteria (image quality score, diagnostic outcome, relative diagnostic confidence score) in all patients, and three quantitative criteria (infarct volume, infarct signal-to-noise ratio [SNRinf], and infarct-viable myocardium contrast-to-noise ratio [CNRinf-myo]) in patients with hyperenhanced myocardium. Results Compared to 2DBH DE-MRI, 3DNAV DE-MRI provided slightly better image quality, the same final diagnostic outcomes, and better relative diagnostic confidence score with 79% SNRinf improvement (P = 0.002) and 90% CNRinf-myo improvement (P = 0.004) in 39% less scan time (414 ± 118 seconds for 2DBH and 251 ± 93 seconds for 3DNAV). The measured infarct volumes demonstrated excellent correlation (18.9 ± 19.0 mL for 2DBH DE-MRI vs. 17.6 ± 19.0 mL for 3DNAV DE-MRI, r2 = 0.998, P < 0.001, N = 7) and narrow limits of agreement (–1.3 ± 1.8 mL). Conclusion 3DNAV DE-MRI provides improved image quality and similar infarct detection in less scan time compared to the standard 2DBH DE-MRI. J. Magn. Reson. Imaging 2008. © 2008 Wiley-Liss, Inc.
Relic H ii regions and radiative feedback at high redshifts

Ultraviolet (UV) radiation from early astrophysical sources could have a large impact on subsequent star formation in nearby protogalaxies, and in general on the progress of cosmological reionization. Theoretical arguments based on the absence of metals in the early Universe suggest that the first stars were likely massive, bright, yet short-lived, with lifetimes of a few million years. Here we study the radiative feedback arising from such stars using hydrodynamical simulations with transient UV backgrounds (UVBs) and persistent Lyman-Werner backgrounds (LWBs) of varying intensity. We extend our prior work in Mesinger et al., by studying a more typical region whose protogalaxies form at lower redshifts, z ∼ 13-20, in the epoch likely preceding the bulk of reionization. We confirm our previous results that feedback in the relic H n regions resulting from such transient radiation is itself transient. Feedback effects dwindle away after ∼30 per cent of the Hubble time, and the same critical specific intensity of J UV ∼ 0.1 × 10 ―21 erg s ―1 cm ―2 Hz ―1 sr ―1 separates positive and negative feedback regimes. This suggests that overall feedback is fairly insensitive to the large-scale environment, overdensity and redshift-dependent halo parameters, and can accurately be modelled in this regime with just the intensity of the impinging UVB. Additionally, we discover a second episode of eventual positive feedback in haloes which have not yet collapsed when their progenitor regions were exposed to the transient UVB. When exposed to the transient UVB, this gas suffers relatively little density depletion but a significant enhancement of the molecular hydrogen abundance, thus resulting in net positive feedback. This eventual positive feedback appears in all runs, regardless of the strength of the UVB. However, this feedback regime is very sensitive to the presence of Lyman-Werner radiation, and notable effects disappear under fairly modest background intensities of J LW ≳ 10- 3 × 10 ―21 erg s ―1 cm ―2 Hz ―1 sr ―1 , assuming the region is optically thin for LW photons. Nevertheless, when exposed to the same LWB, haloes inside relic HII regions always have a higher H 2 abundance and shorter cooling times than haloes outside relic HII regions, allowing gas to cool faster once it finally begins to collapse on to the halo. We conclude that UV radiative feedback in relic HII regions, although a complicated process, seems unlikely to have a major impact on the progress of cosmological reionization, provided that present estimates of the lifetime and luminosity of a Population III star are accurate. More likely is that the build-up of the LWB ultimately governs the feedback strength until a persistent UV background can be established.
Mid‐life and older workers: job displacement and health care coverage

The purpose of this study was to explore factors influencing the likelihood that workers would have health care coverage following job displacement. The sample was drawn from the Current Population Survey: Displaced Worker Supplement (January 1988) and consisted of 840 workers aged 45 years and older. The workers lost jobs because of plant closings, relocations or because of slack work At the time of the survey, 567 displaced workers indicated that they had health care coverage. Logistic analysis revealed that prior health care coverage, new earnings of males and family incomes of $20,000 or more impacted the likelihood that these displaced workers would have health care coverage. However, workers subsequently re-employed in new jobs (over 35 hours a week) were less likely to have health care coverage.
Ketamine, Phencyclidine, and MK‐801 Protect Against Kainic Acid‐Induced Seizure‐Related Brain Damage

Recent evidence implicates the endogenous excitotoxin, glutamate (Glu), in several neurologic disorders, including seizure-related brain damage. Ketamine, phencyclidine, and MK-801, which are noncompetitive antagonists of the N-methyl-D-aspartate (NMDA) subtype of Glu receptor (but do not antagonize kainic acid receptors) were tested in the present study for their effects on behavioral and/or electrographic seizures and seizure-related brain damage induced by kainic acid. Behavioral seizure activity was reduced by these agents, as was spread of electrographic seizures to neocortex, but seizures recorded from deep brain regions such as hippocampus, piriform cortex, and amygdala were not significantly diminished. All three agents prevented seizure-related brain damage in the amygdala, piriform cortex, thalamus, and CA1 region of the hippocampus but conferred little or no protection in the lateral septum and CA3 region of the hippocampus. The regional selectivity of the neuroprotective effect suggests that NMDA receptors may play a more dominant role in seizure-related brain damage in some brain regions than in others. The ability of NMDA antagonists to prevent seizure-related damage in several brain regions without suppressing seizure activity suggests that in these brain regions persistent seizure activity can be maintained by other transmitter systems, with or without NMDA receptor participation, but that seizure-related brain damage is critically dependent on NMDA receptor participation.
Critical parameters and saturation densities of 1,1-dichloro-2,2,2-trifluoroethane

Abstract An optical cell has been used to determine the critical parameters, Tc and ϱc, and densities along the liquid—vapor phase boundary of 1,1-dichloro-2,2,2-trifluoroethane (Refrigerant 123). The critical temperature was found to be 456.87 K and the critical density is 550 kg/m3. The critical pressure was calculated from vapor pressure data to be 36.74 bar, which yields a value of 0.269 for the critical compressibility factor, Zc. Measurement temperatures varied from 298 K to the critical point for the saturated liquid and from 433 K to the critical point for saturated vapor.
The roving palate: North America's ethnic restaurant cuisines

Abstract Although patterns of food consumption, and foodways in general, have profound social, cultural and economic implications, geographers and other social scientists have accorded the topic minimal attention. By examining the identity, number and location of restaurants in the United States and Canada offering self-consciously ‘ethnic’ and regional cuisines, i.e. a form of gastronomic tourism, to largely non-ethnic and extra-regional patrons, we can begin to explore the shifting connotations of ethnicity and the general transnationalization of culture in recent years, as well as changing food preferences. The information available in classified telephone directories for 271 metropolitan areas (the SMSAs of the U.S. and their Canadian equivalents) enables us to chart the larger outlines of the North American ethnic restaurant scene ca. 1980. Analysis of all recent Pennsylvania directories and those of Philadelphia over the period 1920–1980 provides insight into the nonmetropolitan and historical dimensions of the phenomenon. Ethnic restaurant cuisines are now both quite numerous and widespread throughout the continent, and contain dietary items from virtually all the many immigrant groups present, be they major or minor. But the incidence of the cuisines relative to total number of inhabitants or restaurants varies greatly among regions and by category of metropolis. Furthermore, there is usually at best only a weak relationship between the geographic pattern of a given cuisine and that of the related immigrant stock. On the other hand, socioeconomic class, regional culture and volume of affluent visitors seem to be significant determinants. Of special interest are the patterns for the three dominant cuisines, Chinese, Italian and Mexican, and their variants, and the two most important elite cuisines, the French and Japanese.
A Limit on Relative Genericity in the Recursively Enumerable Sets

Work in the setting of the recursively enumerable sets and their Turing degrees. A set X is low if X′, its Turing jump, is recursive in ∅′ and high if X′ computes ∅″. Attempting to find a property between being low and being recursive, Bickford and Mills produced the following definition. W is deep, if for each recursively enumerable set A, the jump of A ⊕ W is recursive in the jump of A. We prove that there are no deep degrees other than the recursive one.Given a set W, we enumerate a set A and approximate its jump. The construction of A is governed by strategies, indexed by the Turing functionals Φ. Simplifying the situation, a typical strategy converts a failure to recursively compute W into a constraint on the enumeration of A, so that (W ⊕ A)′ is forced to disagree with Φ(−;A′). The conversion has some ambiguity; in particular, A cannot be found uniformly from W.We also show that there is a “moderately” deep degree: There is a low nonzero degree whose join with any other low degree is not high.