cssi/SciSciGPT-SciSciNet huggingface dataset:
Human liver acid phosphatases: Purification and properties of a low-molecular-weight isoenzyme

A low-molecular-weight human liver acid phosphatase was purified 2580-fold to homogenity by a procedure involving ammonium sulfate fractionation, acid treatment, and SP-Sephadex ion-exchange chromatography with ion-affinity elution. The purified enzyme contains a single polypeptide chain and has a molecular weight of 14,400 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The amino acid composition of this enzyme (E) is reported. A pH dependence study using p-nitrophenyl phosphate as a substrate (S) revealed the effect of substrate ionization (pKa 5.2) and the participation of a group in the ES complex having a pKa value of 7.8. The enzyme is readily inactivated by sulfhydryl reagents such as heavy metal ions. Alkylation of the enzyme with iodoacetic acid and iodoacetamide causes complete inactivation of the enzyme and this inactivation is prevented by the presence of phosphate ion. The enzyme is also inactivated by treatment with diethyl pyrocarbonate; protection against this reagent is afforded by phosphate ion. The substrate specificity of this enzyme is unusual for an acid phosphatase. Of the many alkyl and aryl phosphomonoesters tested, the only possibly physiological substrate hydrolyzed by this enzyme was flavin mononucleotide, which exhibits a V which is 3-fold larger at pH 5.0 and 6-fold larger at pH 7.0 than that for p-nitrophenyl phosphate. However, the enzyme also catalyzes the hydrolysis of acetyl phosphate at pH 5.0 with a velocity eight times larger than that reported for an acyl phosphatase from human erythrocytes.
Do People Serve as Cues to Smoke

Introduction: Recent research has identified that the environments in which smoking has previously occurred can alone, in the absence of any explicit smoking stimuli (e.g., cigarettes, lighters), serve as cues that induce robust craving to smoke. The goal of the present study was to determine if people can similarly function as smoking and nonsmoking cues capable of directly affecting smokers’ cue-induced craving.
PKCθ is required for alloreactivity and GVHD but not for immune responses toward leukemia and infection in mice

When used as therapy for hematopoietic malignancies, allogeneic BM transplantation (BMT) relies on the graft-versus-leukemia (GVL) effect to eradicate residual tumor cells through immunologic mechanisms. However, graft-versus-host disease (GVHD), which is initiated by alloreactive donor T cells that recognize mismatched major and/or minor histocompatibility antigens and cause severe damage to hematopoietic and epithelial tissues, is a potentially lethal complication of allogeneic BMT. To enhance the therapeutic potential of BMT, we sought to find therapeutic targets that could inhibit GVHD while preserving GVL and immune responses to infectious agents. We show here that T cell responses triggered in mice by either Listeria monocytogenes or administration of antigen and adjuvant were relatively well preserved in the absence of PKC isoform theta (PKCtheta), a key regulator of TCR signaling. In contrast, PKCtheta was required for alloreactivity and GVHD induction. Furthermore, absence of PKCtheta raised the threshold for T cell activation, which selectively affected alloresponses. Most importantly, PKCtheta-deficient T cells retained the ability to respond to virus infection and to induce GVL effect after BMT. These findings suggest PKCtheta is a potentially unique therapeutic target required for GVHD induction but not for GVL or protective responses to infectious agents.
Histological studies of California red scale (Homoptera: Diaspididae) feeding on citrus.

Citrus leaves, fruit, and green twigs infested with adult California red scale, Aonidiella aurantii (Maskell), were sectioned. Numerous observations were made, including length and width of the stylet bundle, proportion of stylet length found in different plant tissues, frequency of stylets terminating in different tissues, frequency of stylet tracks in different tissues, and the pattern of damaged and healthy cells in relation to the path of the stylets. Stylet bundle width and length significantly increased with instar, making it possible to distinguish the stylet bundles of different instars in the plant. The path of the stylets was intracellular, and most of the path travelled through and terminated in parenchyma cells (palisade and spongy mesophyll of leaves, cortex of twigs, and flavedo of fruit), suggesting that parenchyma is the major feeding site of California red scale. Vascular tissue seemed to be avoided by the stylets, especially in leaves; penetration of vascular tissue was more common in twigs. A high frequency of empty stylet tracks (indicating stylet withdrawal) was found in oil glands, suggesting that they were not satisfactory feeding sites. Damaged cells were frequently observed adjacent to but not pierced by the stylets, suggesting that the damage was caused by diffusion of saliva from the stylet path. Interestingly, some of the pierced cells appeared healthy.
SU‐FF‐J‐14: X‐Ray Scatter in a Clinical CBCT System

Purpose: To investigate the magnitude of x‐ray scatter, and to evaluate the effects of scatter related artifacts on a clinical cone‐beam CT(CBCT) system. Method and Materials: The scattered to primary energy fluence ratio (SPR) was measured as a function of cone angle using lead disks of 3 mm thickness placed on a stack of solid water phantom with thickness of 0, 5, 10, 18, 29 cm, representing air (couch only), extremity, chest, abdomen, and pelvis, respectively. The measurement was repeated with and without bowtie filter in the x‐ray beam. The variation of scatter was evaluated by comparing the measurements with the lead disk placed at different positions in the x‐ray field. The effectiveness of increase air‐gap to reduce SPR was also tested using thickness of 18 and 29 cm of solid water phantom. The air‐gap was increased from the minimum allowance of a clinical scan of about 30 cm to the maximum achievable approximately 42 cm for 18 cm phantom and 38 cm for 29 cm phantom. Results: SPR of the CBCT system increases with thickness of the phantom, from 8% for couch only, to 64% for 29 cm depth of solid water phantom at the maximum cone angle with bowtie. For the depth of 29 cm, SPR varies from 26% at 2° cone angle to 64% at 12° with bowtie. The scatter fluence at different locations of the x‐ray field remains constant without a bowtie filter, indicating the scatter kernel is space invariant. However, when using the half‐fan geometry, the scatter increases with fan angles. As the air‐gap increases, the SPR decreases almost linearly. Conclusion: In CBCTimaging, scatter degrades image quality, especially for large body size, even with an anti‐scatter grid. Scatter removal or correction is necessary for quantitative CBCT measurements. Conflict of Interest: Supported by Varian.
Efficacy of intravenous immunoglobulin in the prevention of pneumonia in patients with common variable immunodeficiency.

Abstract Background: Common variable immunodeficiency (CVID) is a primary immune disorder characterized by antibody deficiency and a decrease in serum IgG and IgA, IgM, or both levels at least 2 SDs below the mean for age and not attributed to other known immunologic disorders. These patients often present with frequent and severe episodes of pneumonia before diagnosis. The standard treatment, intravenous immunoglobulin (IVIG), has been available for the past 20 years. No large-scale study has compared the incidence of pneumonia in these patients before and after IVIG treatment. Objective: The aim of this study was to document the effectiveness of intravenous immunoglobulin treatment on the incidence of pneumonia in patients with CVID. Methods: We performed chart reviews and interviews of patients with laboratory-confirmed CVID seen at our clinical center. The number of episodes of pneumonia was documented before and after treatment with immunoglobulin replacement therapy. Results: The histories of 50 patients were reviewed (mean current age, 42 ± 16.3 years; age range, 10-78 years; 20 male and 30 female patients). Forty-two (84%) of the 50 patients with CVID had pneumonia at least once before receiving immunoglobulin treatment, and 11 of 42 of these patients had multiple episodes. After treatment with gamma globulin over a mean period of 6.6 ± 5.2 years (range,
Role of the midbrain in interhemispheric integration.

1. At the mesencephalic level there are three systems of structural connections responsible for functional relations between the two halves of the forebrain. 2. One of these systems of connections (commissural connections between the superior colliculi) conducts afferent modality-specific (visual) influences, the second (reticular connections) conducts efferent (effector) influences, and the third system (colliculo-reticular connections) evidently conducts efferent and coordinating influences. 3. At the mesencephalic level a system of structural connections is distinguished which participate in functional integration of the forebrain as a single entity. It consists of functional projections of each superior colliculus to the contralateral posterior thalamic group of nuclei through the reticular formation alone and (or) through the reticular formation and contralateral superior colliculus.
Internet robotics: an educational experiment

Robotics is a subject which captures the imagination of undergraduate students in many disciplines including Computer Science and Mechanical Engineering. Despite this interest, when the topic is covered at all in an undergraduate program, the critical hands-on component of the course is often omitted. This is due to a number of causes ranging from the complexity of the subject to the availability of equipment. This paper describes a project to allow experimentation with robots through the Internet for the purpose of undergraduate education. An experimental system has been developed which links computer science students at the University of Wisconsin/LaCrosse with robots and Mechanical Engineering Students at Wilkes University, Wilkes-Barre PA. Unlike such systems constructed for the purpose of experimentation with time delay for shallow space or undersea manipulation, the focus of this system is the education of undergraduate students. This paper discusses how the educational goals affect the design of this system as well as the selection of tasks. Although there are clear advantages in capital and maintenance costs to sharing equipment, the emphasis here is on the significant educational benefits of this type of system. We show that remote operation leads to an understanding of the complexity and difficulty in specifying robot motions for an uncontrolled environment. This understanding is very difficult to achieve in a simulated or local settings where students have much greater control over the execution environment of the robot. The system was constructed in the summer of 1995, with experiments performed during the fall semester of 1995. Results of the experiments run by the joint undergraduate research groups as well as the associated educational outcomes are presented.
In vitro Analysis and Quantitative Prediction of Efavirenz Inhibition of Eight Cytochrome P450 (CYP) Enzymes: Major Effects on CYPs 2B6, 2C8, 2C9 and 2C19

In order to quantitatively predict drug interactions associated with efavirenz-based anti-HIV therapy, we evaluated reversible and time-dependent inhibitions of efavirenz on eight cytochrome P450 (CYP) enzymes in vitro. The present study showed that efavirenz was a potent competitive inhibitor of CYP2B6 (average K(i) = 1.68 µM in HLMs and K(i) = 1.38 µM in expressed CYP2B6) and CYP2C8 (K(i) = 4.78 µM in pooled HLMs and K(i) = 4.80 µM in HLMs with CYP2C8*3/*3 genotype). Efavirenz was a moderate inhibitor of CYP2C9 (K(i) = 19.46 µM) and CYP2C19 (K(i) = 21.31 µM); and a weak inhibitor of CYP3A (K(i) = 40.33 µM). No appreciable inhibition was observed on CYP1A2, CYP2A6 or CYP2D6. No time-dependent inhibition of the CYPs by efavirenz was observed in this study. Quantitative predictions showed that single dose of efavirenz may substantially slow the elimination of drugs predominantly cleared by CYP2B6, CYP2C19 or by both enzymes and may also lower the area under the plasma concentration time curve (AUC) of active metabolites of some pro-drugs (e.g., clopidogrel and proguanil) by up to 30%. Depending on substrates, chronic administration of efavirenz may increase the AUC of CYP2C8 and CYP2C9 substrates about 3.5-4.4-fold and 1.7-2.0-fold at steady state.
Temperature and Salt Dependence of Higher Order Structure Formation by Antisense c-myc and c-myb Phosphorothioate Oligodeoxyribonucleotides Containing Tetraguanylate Tracts

The use of complementary RNA or DNA sequences to selectively interfere with the utilization of mRNA of a target gene is an attractive therapeutic strategy. Two well-studied targets for oligonucleotide therapy are the c-mycand c-mybproto-oncogenes. It has been reported that sequences which contain four contiguous Gs can elicit a non-antisense response, due to the formation of a homotetrameric G quartet structure. Therefore, it was of interest to determine whether anti-c-mycand anti-c-mybphosphorothioate DNAs including tetraguanylate form higher order structures under physiologically relevant salt conditions and temperature. First, the identity of the higher order structure was established and was found to be a tetraplex. Employing intracellular (high K+), extracellular (low K+) and normal saline (no K+) salt mixtures, native gel electrophoresis revealed no tetraplex formation at 37 degrees C, the physiologically relevant temperature. On the other hand, tetraplex structure formation was observed at 4 and 23 degrees C. Hence, the potential for these sequences to form tetraplex structures at lower temperatures may not be relevant for their activity in cells and animals at physiological temperature.
Interaction of fatty acid with myoglobin

Upon titration with palmitate, the (1)H NMR spectra of metmyoglobin cyanide (MbCN) reveal a selective perturbation of the 8 heme methyl, consistent with a specific interaction of myoglobin (Mb) with fatty acid. Other detectable hyperfine shifted resonances of the heme group remain unchanged. Mb also enhances fatty acid solubility, as reflected in a more intense methylene peak of palmitate in Mb solution than in Tris buffer. Ligand binding analysis indicates an apparent palmitate dissociation constant (K(d)) of 43microM. These results suggest that Mb can bind fatty acid and may have a role in facilitating fatty acid transport in the cell.
Explosive Diffusion And Phonon Screening By Photogenerated Carrier Density

Photoluminescence kinetics measured by streak camera at high photogenerated carrier density in CdSe is attributed to screening of electron phonon interaction and enhanced diffusion.
Perceived discrimination, depressive symptoms, and substance use in young adulthood

Perceived discrimination is an important health-related stressor. As suggested by the stress-coping model, substance use often serves as a means to reduce the negative effects of perceived discrimination. This study uses data from the National Survey of American Life-Adults to examine the structural relationship of perceived discrimination and depressive symptoms with lifetime and recent substance use among African American and African Caribbean young adults. Respondents (N=1910) were 18-35 years old. Compared with African Caribbeans, African Americans report significantly higher levels of depressive symptoms and both lifetime and recent substance use. Multiple-group structural equation modeling is used to evaluate model fit and test hypothesized models. Results show good fit of the hypothesized models in both African Americans and African Caribbeans. Full measurement and structural invariance is found across ethnicity. Mediation models explain 18.5% and 47.4% of the variance in lifetime substance use for African Americans and African Caribbeans, respectively, and 23.5% and 35.0% of the variance in recent substance use for African Americans and African Caribbeans, respectively. Mediation tests indicate depressive symptoms partially mediate the relationship between perceived discrimination and lifetime substance use and fully mediated this relationship for recent substance use. This study is the first to demonstrate a positive association between perceived racial discrimination and substance use among African Caribbean young adults. Study findings illuminate the influence of perceived discrimination on substance use and the mechanisms of this relationship among African American and African Caribbean young adults.
Prediction of blood loss during surgery on the lumbar spine with the patient supported prone on the Jackson table.

Abstract Background context To date, many studies have examined the effects of one or several factors on blood loss during lumbar spine surgery. The nature and extent of the operation, patient position, blood pressure, and a variety of factors related to patient size have been touted as predictors of blood loss. Purpose To measure multiple factors implicated as determinants of blood loss and develop a multivariable statistical model capable of predicting blood loss. Study design An observational study of patients undergoing lumbar spine surgery in the prone position on the Jackson table. Patient sample A total of 71 healthy adult men and women undergoing lumbar spine surgery in a university hospital setting. Outcome measure Blood loss during surgery. Methods We observed 35 surgeries and recorded demographic and body habitus data on each patient as well as surgical variables, blood pressure, and peripheral venous pressure. We measured bladder pressure intermittently as a surrogate for intra-abdominal pressure. We constructed a statistical model with the results and validated that model in a separate set of 36 subjects. Results The Jackson table supported all our patients regardless of body dimensions without causing an increase in bladder pressure. Blood loss during surgery averaged 1,167±998 mL (mean±1 standard deviation, range 32–3,745). The statistical model was able to account for about 75% of the variability in blood loss using four variables: the number of laminectomies, whether bone was harvested from the iliac crest, experience of the surgeon doing the initial exposure and closure, and distension of the epidural veins. Data on these variables that were collected in the validation study found a multiple correlation coefficient (R 2 ) of 0.66 between predicted and observed blood loss. Conclusions This is the first study to build a successful multivariable predictive model of blood loss during spine surgery. The Jackson table was effective in supporting patients with different body sizes and shapes, thus removing raised intra-abdominal pressure as an important factor.
Comparative genomics and site-directed mutagenesis support the existence of only one input channel for protons in the C-family (cbb3 oxidase) of heme-copper oxygen reductases.

Oxygen reductase members of the heme−copper superfamily are terminal respiratory oxidases in mitochondria and many aerobic bacteria and archaea, coupling the reduction of molecular oxygen to water to the translocation of protons across the plasma membrane. The protons required for catalysis and pumping in the oxygen reductases are derived from the cytoplasmic side of the membrane, transferred via proton-conducting channels comprised of hydrogen bond chains containing internal water molecules along with polar amino acid side chains. Recent analyses identified eight oxygen reductase families in the superfamily: the A-, B-, C-, D-, E-, F-, G-, and H-families of oxygen reductases. Two proton input channels, the K-channel and the D-channel, are well established in the A-family of oxygen reductases (exemplified by the mitochondrial cytochrome c oxidases and by the respiratory oxidases from Rhodobacter sphaeroides and Paracoccus denitrificans). Each of these channels can be identified by the pattern of conserve...
Recent results and fabrication of micro-pocket fission detectors (MPFD)

Micro-Pocket Fission Detectors (MPFD) have been developed as real-time in-core neutron flux monitors. Tests have demonstrated linear operation with neutron flux varying through six orders of magnitude while surviving neutron fluences greater than 10 16 n . cm -2 . Their design is naturally background insensitive with high signal to noise pulses. Built from alumina ceramics, these devices are relatively simple to build and are inexpensive. They have been designed for fabrication into large arrays to facilitate 3-D mapping of a reactor core.
Absorption of Inhaled NO2

Nitrogen dioxide (NO_2), a sparingly water-soluble π-radical gas, is a criteria air pollutant that induces adverse health effects. How is inhaled NO_2(g) incorporated into the fluid microfilms lining respiratory airways remains an open issue because its exceedingly small uptake coefficient (γ 10^(−7)−10^(−8)) limits physical dissolution on neat water. Here, we investigate whether the biological antioxidants present in these fluids enhance NO_2(g) dissolution by monitoring the surface of aqueous ascorbate, urate, and glutathione microdroplets exposed to NO_2(g) for 1 ms via online thermospray ionization mass spectrometry. We found that antioxidants catalyze the hydrolytic disproportionation of NO_2(g), 2NO_2(g) + H_2O(l) = NO_3^−(aq) + H^+(aq) + HONO, but are not consumed in the process. Because this function will be largely performed by chloride, the major anion in airway lining fluids, we infer that inhaled NO_2(g) delivers H^+, HONO, and NO_3^− as primary transducers of toxic action without antioxidant participation.
Loss of cables is associated with development of endometrial hyperplasia and cancer

Background: Cables is a cell cycle regulatory protein and tumor suppressor(1,2). Cables can interact with cyclin dependent kinases (cdk)(2,3) and it appears to modulate cdk activity by enhancing cdk phosphorylation. Loss of Cables has been associated with the development of squamous cancers of the head and neck(4) and colon(4), ovarian(5) and endometrial cancer (EC)(1). Furthermore, there is a coordinate loss of Cables associated with endometrial hyperplasia suggesting that Cables my play an early role in the transformation of the endometrium. The functional importance of Cables was only recently realized in the Cables mutant mouse which developed endometrial hyperplasia and following exposure to chronic estrogen developed endometrial adenocarcinoma(1). These results combined with the finding that Cables expression is elevated during the progesterone dominant secretory phase of the menstrual cycle would suggest that loss of Cables may serve to promote type 1 endometrial cancer(6,7). It is not known, however, if Cables is lost in the high-grade endometrioid, serous and/or clear cell cancers. High-grade endometrioid, serous and/or clear cell endometrial cancer (EC) are often referred to as type 2 EC(6,7). In addition, it is not known whether Cables inhibits cell proliferation in EC cell lines and/or whether its expression in well-differentiated and poorly differentiated EC cells is hormonally regulated. Objective: Experiments were conducted to address whether Cables is lost in high-grade EC, its expression is hormonally regulated and whether it had the potential to inhibit proliferation in well-differentiated and/or poorly differentiated EC cells in vitro and in vivo. Results: Cables expression is lost in the high-grade endometrioid, serous and clear cell carcinoma similar to what is observed in low-grade endometrioid cancer with greater than 80% showing either complete or partial Cables loss. Treatment with progesterone increased cables expression in well-differentiated EC cells (Ishikawa) whereas it had no effect on cables expression in poorly differentiated EC cells (SK-UT2). The progesterone-induced increase in cables was abrogated in the presence of a progesterone receptor (PR) antagonist, suggesting the PR mediates the increase through the classical nuclear receptor. Immunocompromised mice which hosted well-differentiated EC cells overexpressing Cables had little to no evidence of tumor whereas the majority of the animals which hosted the parent cell line developed excessive tumor burden. Conclusions: Collectively these results suggest that Cables is an important regulator of cell proliferation and an early loss of Cables expression may contribute to the development of EC.
Analysis of electrical equivalent circuit of quartz crystal resonator loaded with viscous conductive liquids

An electrical equivalent circuit of quartz crystal resonator (QCR), with modified electrodes, loaded with a viscous conductive liquid is proposed. The electrode in contact with the liquid is modified so as to create an unmetallized crystal surface in contact with the liquid and thus to introduce an acoustoelectric interaction at the crystal | liquid interface. The admittance—impedance characteristics of the equivalent circuit of the loaded QCR are analyzed to obtain expressions for the changes in the series and parallel resonant frequencies in terms of the liquid viscosity ηL, density ϱL, dielectric constant ϵL, and conductivity σ, as well as the quartz parameters and electrode area geometry. Using a network analyzer, the S parameters of the equivalent circuit of various conductive liquid-loaded QCRs are measured and analyzed. It is shown that in addition to being a well-known detector of mechanical properties of liquids, a QCR, when properly designed, can be used to monitor the electrical properties of dilute ionic solutions.
BLINC: A testbed for nulling interferometry in the thermal infrared

A key technology in NASA's plans for a Terrestrial Planet Finder is nulling interferometry in the thermal infrared. This technique suppresses the overwhelming light from a star in order to study its immediate surroundings. To further develop nulling interferometry we have built the BracewelL Infrared Nulling Cryostat (BLINC). The instrument is designed to achieve high precision cancellation of an artificial source in the lab and of starlight on the telescope. Our goal is to achieve suppression of > 10,000 both with a laser source and a broadband source over a 20% bandwidth. This is sufficient for ground-based observations with even short baseline interferometers since the finite diameter of the star does not allow suppression greater than that for most nearby sources. BLINC uses two parts of the MMT pupil to create an interferometer of 2.7 m diameter elements separated by 4 m. Active compensation for phase variations between the two apertures will be used to maintain the cancellation of the starlight in the presence of atmospheric turbulence. When combined with the adaptive secondary of the MMT to remove high order aberrations, BLINC will be able to achieve suppression of 10,000. This will allow detection of zodiacal dust around nearby stars as faint as 10 times the solar level and detection of companions large than 10 Jupiter masses for systems less than one billion years old. BLINC serves as a prototype for nulling with the Large Binocular Telescope which will be able to see zodiacal dust as faint as solar level and Jupiter mass or larger companions. Thus both in technological and scientific background BLINC will help begin the search for Earth-like planets.
Creativity as Flexible Cognitive Control

Creative individuals have been described in terms suggestive of greater automatic processing (e.g., defocused attention, looser associations) and greater controlled processing (e.g., greater abilities to focus while working on a creative task). Both views cannot be correct from a static ability-related perspective. On the other hand, both views could be correct if creative individuals are better able to modulate the functioning of their cognitive control system in a context-sensitive manner. The present study (N 50) assessed individual differences in creativity in terms of original responses on the Torrance Test of Creative Thinking (Torrance, 1974) and also in terms of creative behavior on the Creative Achievement Questionnaire (Carson, Peterson, & Higgins, 2005). The same participants performed a color–word Stroop task. Creative individuals were neither more nor less capable of overriding cognitive conflicts on incongruent (relative to congruent) Stroop trials. On the other hand, creative individuals displayed more flexible cognitive control, as defined by greater cognitive control modulation from trial to trial. Implications for theories of creativity and its underlying processing basis are discussed.
Technical Note The footprint: a method for checking femoral tunnel placement

Anterior placement of the femoral tunnel during anterior cruciate ligament reconstruction results in nonisometric placement, and posterior placement can lead to posterior tunnel blow out or troughing. Creating a pretunnel footprint before final placement and drilling allows the surgeon to visually verify that proper femoral tunnel placement has been obtained.
Pb(II) coordination and synergistic ion-exchange extraction by combinations of sulfonamide chelates and 2,2'-bipyridine.

The disulfonamide ligands 1,2-C6H4(NH2SO2C6H5)2 (1) and 1,2-C6H4(NH2SO2C6H4-p-But)2 (2), which are readily available in good yields from o-phenylenediamine and the corresponding sulfonyl chlorides, efficiently extract Pb(II) from water into 1,2-dichloroethane when used in synergistic combinations with 2,2‘-bipyridine via an ion-exchange mechanism. The extraction was shown to proceed via the formation of a ternary Pb-sulfamido-2,2‘-bipyridine complex. The X-ray crystal structure of the binary Pb-sulfamido complex 3 shows a coordination polymer with a stereochemically active lone pair on Pb formed by SOPb axial coordination.
The impact of ethnicity, gender, and marital status on periodontal and systemic health of older subjects in the Trials to Enhance Elders' Teeth and Oral Health (TEETH).

Background: Few studies have examined the association between periodontitis risk, gender, and marital status in older adults. The purpose of this study was to assess if the oral health status of older subjects could be explained by differences in: 1) marital status; 2) gender; and 3) ethnicity. Methods: Clinical and radiographic periodontal oral conditions were studied in 701 older subjects from the TEETH clinical trial. Medical conditions as well as ethnic and marital status and smoking habits were considered. Results: A total of 89 married couples were identified; 40.7% of these were of European descent and 48.1% of Chinese descent. The mean age was 67.7 years (SD ± 4.7). The men were older than the women (mean difference: 1.5 years, SD ± 4.6, 95% confidence interval [CI]: 0.5 to 2.5, P <0.01). No significant differences in periodontal conditions were found between spouses or by marital status. Chinese descent was associated with a higher risk for periodontitis, regardless of marital status (odds ratio:...
Computational procedure for the sensitivity of an eigenvalue

An easily computable formula is given for calculating the sensitivity of an eigenvalue to changes in the matrix. This formula depends only on the eigenvalue of interest, the matrix and the changes in the matrix.
Fluorescence correlation spectroscopy simulations of photophysical phenomena and molecular interactions: a molecular dynamics/monte carlo approach.

Fluorescence correlation spectroscopy (FCS) is being applied increasingly to study diffusion and interactions of fluorescently labeled macromolecules in complex biological systems. Fluctuations in detected fluorescence, δF(t), are expressed as time-correlation functions, G(τ), and photon-count histograms, P(k;ΔT). Here, we developed a generalized simulation approach to compute G(τ) and P(k;ΔT) for complex systems with arbitrary geometry, photophysics, diffusion, and macromolecular interactions. G(τ) and P(k;ΔT) were computed from δF(t) generated by a Brownian dynamics simulation of single-molecule trajectories followed by a Monte Carlo simulation of fluorophore excitation and detection statistics. Simulations were validated by comparing analytical and simulated G(τ) and P(k;ΔT) for diffusion of noninteracting fluorophores in a three-dimensional Gaussian excitation and detection volume. Inclusion of photobleaching and triplet-state relaxation produced significant changes in G(τ) and P(k;ΔT). Simulations of...
Strategies for Improving Power in School-Randomized Studies of Professional Development.

Objectives:Group-randomized designs are well suited for studies of professional development because they can accommodate programs that are delivered to intact groups (e.g., schools), the collaborative nature of professional development, and extant teacher/school assignments. Though group designs may be theoretically favorable, prior evidence has suggested that they may be challenging to conduct in professional development studies because well-powered designs will typically require large sample sizes or expect large effect sizes. Using teacher knowledge outcomes in mathematics, we investigated when and the extent to which there is evidence that covariance adjustment on a pretest, teacher certification, or demographic covariates can reduce the sample size necessary to achieve reasonable power.Method:Our analyses drew on multilevel models and outcomes in five different content areas for over 4,000 teachers and 2,000 schools. Using these estimates, we assessed the minimum detectable effect sizes for several s...
Serpin-Derived Peptides Are Antiangiogenic and Suppress Breast Tumor Xenograft Growth

Angiogenesis is the formation of neovasculature from preexisting microvessels. Several endogenous proteins regulate the balance of vessel formation and regression in the body including pigment epithelium-derived factor (PEDF), which has been shown to be antiangiogenic and to suppress tumor growth. Using sequence homology and bioinformatics, we previously identified several peptide sequences homologous to an active region of PEDF existing in multiple proteins in the human proteome. These short 11-mer peptides are found in a DEAH box helicase protein, CKIP-1 and caspase 10, and show similar activity in altering endothelial cell adhesion, migration and inducing apoptosis.We tested the peptide derived from DEAH box helicase protein in a triple-negative MDA-MB-231 breast orthotopic xenograft model in severe combined immunodeficient mice and show significant tumor suppression.
Robust initialization of active shape models for lung segmentation in CT scans: a feature-based atlas approach

Model-based segmentation methods have the advantage of incorporating a priori shape information into the segmentation process but suffer from the drawback that the model must be initialized sufficiently close to the target. We propose a novel approach for initializing an active shape model (ASM) and apply it to 3D lung segmentation in CT scans. Our method constructs an atlas consisting of a set of representative lung features and an average lung shape. The ASM pose parameters are found by transforming the average lung shape based on an affine transform computed from matching features between the new image and representative lung features. Our evaluation on a diverse set of 190 images showed an average dice coefficient of 0.746 ± 0.068 for initialization and 0.974 ± 0.017 for subsequent segmentation, based on an independent reference standard. The mean absolute surface distance error was 0.948 ± 1.537 mm. The initialization as well as segmentation results showed a statistically significant improvement compared to four other approaches. The proposed initialization method can be generalized to other applications employing ASM-based segmentation.
Generalized coherent-potential method for disordered systems. II. Numerical results

An elaboration and numerical study is presented for a coherent-potential-alloy (CPA) theory which gives the next step beyond the single-site CPA by including nearest-neighbor correlations. The theory includes all aspects of disorder including short-range order. Although the theory does not strictly have the Herglotz property, it gives physically reasonable results. Numerical results are presented for the electron density of states of binary alloys which show the effects of diagonal and off-diagonal disorder, nearest-neighbor correlations, shielding of the potential, and short-range order. Short-range order is shown to have the largest effect on the shape of the density of states.
Protonation-deprotonation of purines and purine nucleosides

Abstract The protonation of purines and purine nucleosides at N7 and the HC8 acidity of the cations have been explored by semi-empirical and ab initio MO calcul
Recent results from HELIOS

Transfer and inelastic scattering reactions using light-ion beams and stable or long-lived targets have traditionally provided detailed information on the structure of nuclei near the line of beta stability. Such studies can now be extended to nuclei away from the line of β -stability as radioactive beams are becoming available at a number of facilities around the world, including the CARIBU facility at Argonne. These measurements must, however, be carried out in inverse kinematics, resulting in a loss of the effective experimental resolution when conventional detection schemes are employed. The HELIOS spectrometer is based on a new concept, that is especially well suited for such studies by reducing the resolution problem, providing simple particle identiﬁcation, and giving high detection eﬃciency with moderate Si detector area. In this talk, the HELIOS concept and results from the ﬁrst series of experiments will be presented.
Cadmium-induced changes in deer mouse seminiferous tubules

Twenty-four male deer mice, 10–12 weeks old, were exposed to drinking water containing cadmium chloride (CdCl2) at 20 ppm for 30 days. At that point, the weighed mice were sacrificed and testes were excised, weighed, and processed for routine histologic evaluation. Compared to control animals, there was no change in the body or testis weights of mice exposed to CdCl2. Tailless spermatozoa were observed in some seminiferous tubules of testes from CdCl2-treated mice. Some tubules of CdCl2-treated mice displayed exaggerated intercellular spaces; in certain tubules, this cellular separation was profound. There appeared to be a reduction in the number of Sertoli cells.
Pathogenicity of Clinical Acinetobacter baumannii Isolates in a Galleria mellonella Host Model according to blaOXA-40 Gene and Epidemiological Outbreak Status

Clinical studies have suggested that blaOXA-40-positive Acinetobacter baumannii isolates are associated with poor patient outcomes; however, reasons for unfavorable outcomes are difficult to discern in clinical studies. The objective of this study was to assess the virulence of carbapenem-resistant A. baumannii according to blaOXA-40 and epidemiological outbreak status in a Galleria mellonella model. Eight isolates of A. baumannii were studied. Nonoutbreak isolates and blaOXA-40-negative isolates more rapidly killed infected G. mellonella (P < 0.01).
Fast Parallel Algorithms for QR and Triangular Factorization

We present a family of new fast algorithms for QR factorization of certain structured matrices, including rectangular Toeplitz matrices and a variety of other Toeplitz-like matrices. It possesses a very regular structure, and appears to be very convenient for parallel implementation. Moreover it is shown that the same architecture can be used for either triangular factorization or QR factorization. Our approach separates the conceptual and implementational aspects of the problem. Our analysis reveals a variety of algorithmic implementations of the basic procedure, all with potentially different numerical properties that need further examination.Our approach is based on the observations that the matrix ${\bf R}$ in ${\bf A} = {\bf {QR}}$ is the Cholesky factor of ${\bf A}^T {\bf A}$ and that fast algorithms for Cholesky factorization of positive definite Toeplitz and certain “close-to-Toeplitz” matrices are readily obtained via a so-called displacement representation of matrices. In this paper we show that if ${\bf A}$ is Toeplitz or is expressed in suitable displacement form then ${\bf A}^T {\bf A}$ also has such a displacement representation, so that ${\bf R}$ can be obtained by a suitable fast Cholesky algorithm. The matrix ${\bf Q}$ is then found by extending a result, also presented in this paper, that ${\bf R}$ and ${\bf R}^{ - 1} $ can be found simultaneously by appropriate circular and hyperbolic rotations applied to a matrix (with Toeplitz blocks) constructed from the elements of ${\bf A}$.
Egress Simulation Incorporating Social Relationships by Using Scalar Field Method

Research on human evacuation is heavily dependent on simulation. However, many of the models developed to date lack realism because of their inability to adequately simulate social relationships. In order to create a better tool for studying human response during evacuation, an agent-based model is proposed based upon a new technique termed Scalar Field Method (SFM). Drawing on analogy to a charged particle in an electromagnetic field, both human will and social relationships are converted into virtual potential energies (VPEs) to simulate the interactions that occur between an agent and its surrounding entities. Each agent has stochastic characteristics, is independent and makes autonomous decisions on behavior by minimizing the VPE. Preliminary tests show the ability of the new model to mimic reasonable evacuation behavior, and its potential for exploring the significance of social relationships during egress.
High-speed multiplier for digital signal processing

A high-speed optical system capable of performing n -bit multiplication in a time proportional to log 2 n is presented. The simultaneous generation and the optical regrouping of all the partial products and the pairwise addition of the partial products by means of a binary tree of adders capable of adding any two numbers in a single stage (by completely eliminating the carry propagation chain) are unique features of this multiplier. The input data to the multiplier can be in either a binary or a modified signed digit number system. The simultaneous generation and the pairwise addition of the partial products are accomplished by means of the principle of symbolic substitution logic that was originally proposed by Brenner.
Adiabatic demagnetization refrigerators for small laboratory experiments and space astronomy

An overview is given of the general principles and techniques used for the design and construction of compact, portable adiabatic demagnetization refrigerators (ADRs). The paper covers methods of salt pill suspension, magnet technology, lead design, heat switches and temperature readouts, as well as considerations for space qualification. Performance specifications are given for an ADR which was originally developed for cooling infrared detectors on the Space Infrared Telescope Facility (SIRTF). This ADR is presently used on the balloon-borne Millimeter Wave Anisotropy Experiment (MAX) for measuring anisotropy in the cosmic microwave background. Comparisons are made with other ADRs under development for use in space or on rockets.
Sequence of the Candida albicans erg7 gene

The nucleotide sequence of the Candida albicans erg7 gene, which complements erg7 mutants of Saccharomyces cerevisiae and restores oxidosqualene cyclase activity, was determined. The gene encodes a 728-aa protein that displays homology with squalene-hopene cyclase, providing further evidence that erg7 is the gene encoding 2,3-oxidosqualene cyclase.
Some formulas for estimating tracking errors

Abstract Universal curves and approximate formulas for the elements of the track parameter error matrix are derived for homogeneous tracking detectors in the continuous measurement limit.
Separation of liquid mixtures by capillary distillation

Abstract Capillary distillation utilizes the effects of the solid-liquid interfacial molecular forces, i.e. dispersion interactions and polar interactions, to alter the vapor-liquid equilibria of liquid mixtures to be separated by distillation using capillary plates -fractionating plates having capillary-type passages (1, 1a, 1b, 1c and 1d). Several azeotropic systems have been investigated and their separations have been demonstrated to various industries in the U.S.A. interested in liquid separation thus showing the practicality and usefulness of this radically new separation technology (16–18). Numerous binary solutions have been investigated for their separation by capillary distillation resulting in unusually high separation and thermal efficiencies with very small pressure drops (2–5, 9–15, 19). In this paper, only some typical separation experiments and their results are reported to show the very unique nature of capillary distillation. The systems reported herein include: acetic acid-water mixtures and azeotropic mixtures of ethyl alcohol-water, of 1-propyl alcohol-water, of acetone-methyl alcohol, and of acetonitrile-ethylene dichloride. Very high Murphree plate efficiencies exceeding 100% (often several hundreds or thousands percent) were obtained in most cases due to the fact that the concentration of the vapor leaving the capillary plate, yn, is higher than that which would have been obtained if the vapor leaving the plate had been in equilibrium with the liquid leaving the plate, ynsu*. In many instances, Murphree plate efficiencies(%) obtained were negative numbers due to the fact that the concentration of the vapor from the plate below, yn+1, is higher than ynsu* indicating that the vapor-liquid equilibria have been altered by the solid-liquid interfacial molecular forces. The effects of the vapor rate and liquid height upon Murphree plate efficiencies and pressure drop per plate, and the thermal efficiencies of capillary plate reported earlier (1, 20) are recapitulated to illustrate the very unique operational characteristics of capillary distillation. The separation characteristics, especially mechanisms of capillary distillation , is not completely understood at this time.
What can be inferred about the ion-transporting properties of a membrane from measurements of resting potential, tangential resistance, and tracer flux?

Abstract The term transport ionophore is introduced and defined as a membrane inclusion which facilitates the passage of ions between the two aqueous phases bounding a bilayer membrane. This concept is then used to derive formulations for the membrane currents and the undirectional ion fluxes in terms of the several species of transport ionophores (which are presumed to be biochemically unambiguous) rather than in terms of the more traditional ion-specific channels and pumps (which are commonly thought to be of less than ideal selectivity). It is shown how membrane currents so defined can be reduced, by imposing a few simple but explicit conditions, to the usual simple equivalent circuit models or dichotomized into passive fluxes versus active fluxes; however, it is also shown that many experiments which seek such models or dichotomies fail to satisfy one or more of the imposed conditions and thus are not rigorously interpretable. Finally, it is concluded that the transport ionophore approach, though it fits much more naturally with the biochemical reality of the membrane than the more traditional approaches, will achieve its full potential only when the isolation and characterization of the several individual transport ionophores of an arbitrary membrane becomes more routinely possible.