cssi/SciSciGPT-SciSciNet huggingface dataset:
Pathogenetic sequence for aneurysm revealed in mice underexpressing fibrillin-1

Dissecting aortic aneurysm is the hallmark of Marfan syndrome (MFS) and the result of mutations in fibrillin-1, the major constituent of elastin-associated extracellular microfibrils. It is yet to be established whether dysfunction of fibrillin-1 perturbs the ability of the elastic vessel wall to sustain hemodynamic stress by disrupting microfibrillar assembly, by impairing the homeostasis of established elastic fibers, or by a combination of both mechanisms. The pathogenic sequence responsible for the mechanical collapse of the elastic lamellae in the aortic wall is also unknown. Targeted mutation of the mouse fibrillin-1 gene has recently suggested that deficiency of fibrillin-1 reduces tissue homeostasis rather than elastic fiber formation. Here we describe another gene-targeting mutation, mgR, which shows that underexpression of fibrillin-1 similarly leads to MFS-like manifestations. Histopathological analysis of mgR/mgR specimens implicates medial calcification, the inflammatory–fibroproliferative response, and inflammation-mediated elastolysis in the natural history of dissecting aneurysm. More generally, the phenotypic severity associated with various combinations of normal and mutant fibrillin-1 alleles suggests a threshold phenomenon for the functional collapse of the vessel wall that is based on the level and the integrity of microfibrils.
Lymphocyte deactivation by (potential immunosuppressant) alkylating metabolites of cyclophosphamide.

The potential immunosuppressant activity of the following compounds derived from cyclophosphamide (CPA) was evaluated: 8 known metabolites, oxidation products and hydrolytic products of CPA containing the mustard moiety; the mixture of alkylating products formed from CPA by chemical and biological oxidation in vitro; acrolein. Mechlorethamine (HN2) and mannomustine were included in this survey as reference compounds.
A Numerical Study on the Effect of Water Addition on NO Formation in Counterflow CH4/Air Premixed Flames

The effect of water addition on NO formation in counterflow CH4 /air premixed flames was investigated by numerical simulation. Detailed chemistry and complex thermal and transport properties were employed. The results show that the addition of water to a flame suppresses the formation of NO primarily due to the flame temperature drop. Among a lean, a stoichiometric and a rich premixed flame, the effectiveness of water addition is most significant for the stoichiometric flame and least for the rich flame, since the dominant NO formation mechanism varies. The addition of water also reduces the formation of NO in a flame because of chemical effect that increases the concentration of OH, while reduces the concentrations of O and H. Compared to the stoichiometric flame, the chemical effect is intensified in the lean and rich flames.Copyright © 2005 by National Research Council of Canada
A quantitative method for measuring protein phosphorylation

We have developed a novel method for quantitating protein phosphorylation by a variety of protein kinases. It can be used with purified kinases and their substrates in vitro or in combination with cell extracts. The method is based on the knowledge that protein kinase C (PKC) adds three phosphates to each molecule of its preferred substrate, myelin basic protein (MBP). A time course is performed in which a kinase is allowed to phosphorylate its preferred substrate or the protein under investigation in the presence of [gamma-32P]ATP. At the same time PKC is allowed to fully phosphorylate MBP. After resolving the products by SDS-PAGE, electrophoretic transfer, and determining the degree of incorporation of 32P by phosphorImager analysis, the data are converted to moles phosphate/mole protein by normalization with phosphorylated MBP. The method is both sensitive and relatively rapid and all the steps are commonly available in the biochemistry laboratory. We have used this method to confirm and extend information on the relationship of MEK1 and MAPK/Erk2 in rat lung fibroblasts exposed to V(2)O(5). A 4-h exposure to V(2)O(5) results in partial phosphorylation of MAPK/Erk2 such that 25% of the potential phosphorylation sites are occupied. We also demonstrate that despite multiple potential phosphorylation sites, recombinant human AP endonuclease is weakly phosphorylated in vitro (4% at best) by PKC, cGMP-dependent protein kinase, casein kinase II, and casein kinase I and not at all phosphorylated by MAPK. Furthermore we are unable to demonstrate phosphorylation in cell extracts from HeLa cells, mouse fibroblasts after oxidative damage with H(2)O(2) or alkylation damage with methylmethane sulfonate, or rat lung fibroblasts after oxidative damage with V(2)O(5).
A study of the unsteadiness of crossing shock wave turbulent boundary layer interactions

The unsteadiness of crossing shock wave turbulent boundary layer interactions at a nominal Mach number of 3 was examined by measuring wall pressure fluctuations using multiple, high frequency response, pressure transducers. The unsteadiness in the initial part of the interaction for all the interactions is similar to that of single fin interaction as studied by Tran and Bogdonoff (1987). However, for stronger interactions, flow downstream of the inviscid shock crossing position has a significant unsteady characteristic. In this unsteady region of the interaction, mean surface pressure rises significantly over the value obtained from the inviscid shock approximation. The energy spectrum of the fluctuating pressure signal shows a significant increase in the energy level at the higher frequencies.
Effects of detergent concentration and ethylene oxide chain length of the detergent molecule on stress-cracking of low-density polyethylene

Stress-cracking behaviour of low-density polyethylene is investigated using a fracture mechanics approach. It is experimentally observed thatK l independent crack speed is directly proportional to the concentration of Igepal CO-630 up to 25% concentration.K ISCC is found to increase with detergent concentration; and the increase inK ISCC is attributed to the larger amounts of detergent absorption in the higher concentrations, which decreases the strain localization at the crack tip. Micelle formation of detergents in water is thought to enhance the rate of cracking because of their ability to increase plasticization efficiency at the local area because the micelles contain larger amounts of aggressive molecules. In contrast to Williams' model, the cracking behaviour in the constant crack speed region is found to be not controlled by the flow properties of the environment.
Effect of microcapsules of luteinizing hormone‐releasing hormone antagonist SB‐75 and somatostatin analog RC‐160 on endocrine status and tumor growth in the dunning R‐3327H rat prostate cancer model

Inhibitory effects of sustained delivery systems (microcapsules) of the modern antagonist of luteinizing hormone-releasing hormone [Ac-D-Nal(2)1, D-Phe(4Cl)2, D-Pal(3)3, D-Cit6, D-Ala10]LH-RH (SB-75) or the potent somatostatin analog D-Phe-Cys-Tyr-D-Trp-Lys-Val-Cys-Trp-NH2 (RC-160) were investigated in the Dunning R-3327H rat prostate cancer model. In the first experiment, the treatment was started 4 months after tumor transplantation, when the tumors measured approximately 2 cm3. Tumor volumes and weights were significantly reduced by SB-75 microcapsules releasing 48 micrograms/day or RC-160 microcapsules releasing 38 micrograms/day given alone, as compared with the control. The combination of these two analogs showed a synergistic effect. In the second experiment, the treatment was started 7 months after tumor transplantation, when the tumors were well developed and measured about 16 cm3. In addition to a significant reduction in volume, weight, and growth rate of tumors, histological signs of tumor regression were found in the groups treated with SB-75 microcapsules releasing 72 micrograms/day given alone or in combination with RC-160 microcapsules releasing 76 micrograms/day, but not with RC-160 alone. No synergistic effect of the combination therapy was found in the second experiment. Serum testosterone levels decreased to undetectable levels and LH levels were also diminished within 2 weeks by administration of SB-75 alone or in combination with RC-160. In both experiments, the weights of testes, ventral prostate, and seminal vesicles were greatly reduced by administration of SB-75 alone or in combination with RC-160. Our results suggest that the combined therapy with microcapsules of SB-75 and RC-160, started soon after the diagnosis of prostate cancer is made, could improve therapeutic response.
State P-20 Councils and Collaboration Between K-12 and Higher Education

For decades, numerous observers have agreed on the value of collaboration between K-12 and higher education—especially as these sectors work toward increasing college readiness and success. While most states maintain separate agencies for K-12 and higher education, many states have worked to foster collaboration through state P-20 councils. Policy makers’ interest in these councils has waned somewhat as evidenced by the decreasing number of state councils over the past few years. This may be because while collaboration is easy to initiate, it is difficult to do well and sustain. Therefore, understanding the mechanics of collaboration through P-20 council operations may help to improve their functioning and possibly become a more fruitful tool for states. In this study, three state P-20 councils are examined to understand what, if any, catalysts in the organizational structure of the councils promote collaboration.
Vacuum-assisted closure for complicated neonatal abdominal wounds

Abstract Background Neonatal experience in vacuum-assisted closure (VAC) for complex abdominal wounds remains scant. Methods A neonatal VAC protocol was instituted in 2004. The medical records of patients treated with this protocol for the ensuing 3 years were retrospectively reviewed. Continuous data are reported as mean ± SD (range). Results Ten VAC applications occurred in 8 neonates for a 3-year period. Gestational age and age at VAC application were 30 ± 6.9 (24-40) weeks and 84.5 ± 51 (21-165) days, respectively. Birth weight and weight at VAC application were 1495 ± 1118 (615-3415) g and 3515 ± 2118 (989-7965) g, respectively. All wound complications occurred after laparotomies (7 elective, 3 emergent). Three wounds included intestinal stomas, and 3 included enterocutaneous fistulae. Average wound area at VAC initiation was 13.6 ± 6.0 (8.5-25) cm 2 . Duration of VAC use was 19.1 ± 15.3 (7-60) days. Vacuum-assisted closure resulted in complete wound closure in all cases and did not result in any local or systemic complications. Five patients (63%) survived to discharge. Conclusions Vacuum-assisted closure for complicated abdominal wounds is safe and successful in neonates of any gestational age and birth weight. It provides effective wound management, even in the presence of stomas or enterocutaneous fistulae.
Color exchange in near-forward hard elastic scattering

We study the large-t small-angle behavior of quark-quark elastic scattering. We employ a factorization procedure previously developed for fixed-angle scattering, which depends on the color structure of the factorized hard subprocess. We find an evolution in t that (in leading logarithmic approximation) becomes diagonal in a singlet-octet basis in the t-channel as s → ∞. Octet exchange in the hard scattering is associated with the familiar “reggeized”, sαg(t) behavior, which arises from s-dependence in Sudakov suppression. In contrast, Sudakov suppression for t-channel singletexchange in the hard scattering is s-independent. In general, these contributions are mixed by soft corrections, which, however, cancel in many experimental amplitudes and cross sections.
Enhancement of cold fusion in metal "hydrides" by screening of proton and deuteron charges.

The production of fusion heat in a metal hydride (deuteride) lattice is problematic, since the reported ratio of power to neutron or \ensuremath{\gamma}-ray flux of some workers is much larger than that for any known conventional complement of fusion reactions. However, enhanced screening of the deuteron or proton charge in the lattice cages might enhance to modest levels the standard d+d${\ensuremath{\rightarrow}}^{3}$He+n,T+p and p+d${\ensuremath{\rightarrow}}^{3}$He+\ensuremath{\gamma} fusion reactions. By lowering the effective deuteron-deuteron and proton-deuteron Coulomb barriers, the effective Gamov penetration factor is increased substantially in metals in general, transition metals in particular, and perhaps enough to produce modest neutron fluxes and tritium yields.
Conversion of a power to a series of Chebyshev polynomials

Even slowly convergent power series can be rearranged as series in Chebyshev polynomials if appropriate sequence transformations are used in evaluating the coefficients. The method is illustrated by computing the coefficients for the expansion of the logarithm and dilogarithm.
Preliminary Clinical Evaluation of Hard and Soft Copy Digitized Chest Radiography

The digital applications in radiology are a controversial advanced which potentially will influence all areas of patient imaging. It is utilized and accepted in angiography, computed tomography, magnetic resonance, nuclear imaging and sonography. More recently Computed Radiography has gained credibility in mobile scenarios as well as specific applications from cervical spine radiography to digital fluoroscopy. Usually this acceptance is related to benefits of lesser radiation exposure or an improved presentation with an incorrect radiographic technique. One advantage of interpreting from digital information is the potential manipulation of the image presentation to the observer through windowing, leveling and edge enhancement pre and/or during image review. Additionally this digital data can be transmitted over distance and represented as hard and/or soft copy for primary or consultative review. The number and quality of the images to be viewed, the environment of the review station as well as the observer experience with conventional radiographic as well as digital image evaluation are important aspects of delivering the radiologist's product i.e. the final interpretation. This paper assesses that product, specifically addressing the question `Is the radiologist's report the same whether derived from the original analog image or from its digitized image.' The object of this study is to determine whether a digital system (3M PACS) designed for consultative viewing in a satellite department can also be used directly for primary diagnosis of conventional chest exams.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Microfluidic Chemotaxis Platform for Differentiating the Roles of Soluble and Bound Amyloid-β on Microglial Accumulation

Progressive microglial accumulation at amyloid-β (Aβ) plaques is a well-established signature of the pathology of Alzheimer's disease, but how and why microglia accumulate in the vicinity of Aβ plaques is unknown. To understand the distinct roles of Aβ on microglial accumulation, we quantified microglial responses to week-long lasting gradients of soluble Aβ and patterns of surface-bound Aβ in microfluidic chemotaxis platforms. We found that human microglia chemotaxis in gradients of soluble Aβ42 was most effective at two distinct concentrations of 23 pg.mL−1 and 23 ng.mL−1 Aβ42 in monomers and oligomers. We uncovered that while the chemotaxis at higher Aβ concentrations was exclusively due to Aβ gradients, chemotaxis at lower concentrations was enhanced by Aβ-induced microglial production of MCP-1. Microglial migration was inhibited by surface-bound Aβ42 in oligomers and fibrils above 45 pg.mm−2. Better understanding of microglial migration can provide insights into the pathophysiology of senile plaques in AD.
Two Decades of Homage to Santa Rosalia: Toward a General Theory of Diversity

In 1959, in his seminal paper “Homage to Santa Rosalia,” G. E. Hutchinson asked, Why are there so many kinds of organisms? This paper focused attention on problems of species diversity and community organization that have occupied many theoretical and empirical ecologists for the last two decades. In the present paper I evaluate the attempt to answer Hutchinson's question by considering three topics. First, I reexamine the main themes which Hutchinson developed in “The Homage” and call attention to the central importance of energetic relationships in his view of ecological communities. Second, I examine the development of theoretical community ecology over the last two decades in an attempt to determine why some avenues of investigation, such as competition theory, have proven disappointing, whereas others, such as the theory of island biogeography, have enjoyed at least modest success. Finally, I suggest that future attempts to understand patterns of species diversity might focus on developing two kinds of theoretical constructs: capacity rules, which describe how characteristics of the physical environment determine its capacity to support life, and allocation rules, which describe how limited energetic resources are subdivided among species.
Sequence organization of the origins of DNA replication in lambdoid coliphages.

We have determined the sequences of the ori region DNA of several phage lambda mutants and hybrids, which shed light on the mechanism of DNA replication in the lambdoid phages. These include the heterologous substitution hybrids lambda rep82:lambda and lambda rep80:lambda, a pseudorevertant of the ori-r93 mutant lambda r93hot5, and the insertion mutant lambda pk35. The ori regions of the three lambdoid phages, lambda, phi 80 and 82, all have repeated sequences, termed iterons, and A . T-rich zones. We note that a similar arrangement of DNA is also found in several other prokaryotic origins of replication. lambda and phi 80 have four iterons, and 82 has five. The origin of lambda r93hot5 is unusual in that contains only three iterons, yet the phage grows normally. Analysis of this mutant indicates that the spacing of iterons is crucial to ori function, whereas their number is not. This argues against the cloverleaf model for lambda ori structure (Hobom et al., 1979). In lambda pk35 the drug resistance element Tn903 is inserted into the "inceptor" (ice) site, proposed to be crucial for lambda replication initiation (Hobom et al., 1979); yet this phage grows normally.
Protective effect of intravenous mumps vaccine in early neonatal mice.

SummaryA striking degree of protection from fatal mumps encephalitis is afforded mice if they are injected intravenously with mumps vaccine when less than 4 hours old. A less marked but very significant degree of protection is also afforded by influenza vaccine used in this same way, but none at all using the formalin diluent alone. With advancing age above the four-hour group this sparing effect diminishes. These results may be due to combined effects of viral interference and antibody production.
Reversal of clonidine-induced hypotension by beta-adrenoceptor blocking drugs.

The interaction between clonidine, propranolol and sotalol was investigated using conscious normotensive and spontaneously hypertensive rabbits as well as conscious normotensive and spontaneously hypertensive rats. Clonidine (20 micrograms/kg) administration into the marginal ear vein of rabbits produced persistent hypotension and bradycardia. In propranolol (0.5 mg/kg, i.v.)-pretreated animals, clonidine-induced hypotension was prevented. In rats, daily oral or subcutaneous clonidine as well as propranolol produced hypotension and bradycardia. Significant antagonism of the observed hypotensive effects resulted when clonidine was given to propranolol-pretreated animals or when propranolol was added to the treatment regimen of animals being maintained on clonidine. No antagonism between sotalol and clonidine was demonstrable. In view of the known central site of action of clonidine, and the failure of sotalol to antagonize clonidine-induced hypotension it would appear that the central nervous system is a possible site of the observed drug interaction.
Internet resources integrating many small-molecule databases1

New data, tools and services recently made available on the web server (http://cactus.nci.nih.gov) of the Computer-Aided Drug Design (CADD) Group, NCI, NIH, developed in the context of chemoinformatics and drug development work, are presented. These tools are designed for searching for structures in very large databases of small molecules. One of them is a web service–the Chemical Structure Lookup Service (CSLS)–for very rapid structure lookup in an aggregated collection of more than 80 databases comprising more than 27 million unique structures at the time of this writing. CSLS contains pointers to the entries in toxicology-related databases, catalogues of commercially available samples, drugs, assay results data sets, and databases in several other categories. CSLS allows the user to find out very rapidly in which one(s) of all these databases a given structure occurs independent of the representation of the input structure, by making use of InChIs as well as new CACTVS hashcode-based identifiers. These...
Cutting Edge: Paradoxical Roles of BST2/Tetherin in Promoting Type I IFN Response and Viral Infection

Bone marrow stromal Ag 2 (BST2) is a transmembrane protein that prevents virus release from infected cells. It was also reported that BST2 inhibits type I IFN production by plasmacytoid dendritic cells. To determine BST2 impact on antiviral responses in vivo, we generated BST2(-/-) mice. Following infection with a murine retrovirus, BST2(-/-) mice had slightly elevated viral loads; however, infection with other enveloped viruses revealed unexpected roles of BST2. BST2(-/-) mice showed reduced type I IFN production by plasmacytoid dendritic cells. Moreover, BST2(-/-) mice had lower viral titers in lungs following intranasal infection with vesicular stomatitis virus expressing OVA and influenza B and increased numbers of virus-specific CD8 T cells in the lungs, suggesting that BST2 may facilitate entry and/or replication of enveloped viruses and modulate priming of CD8 T cells. These findings suggest complex roles of BST2 beyond retroviral control in vivo, possibly reflecting the involvement of BST2 in endocytosis and intracellular trafficking of viruses, viral nucleic acids, and Ags.
The Maritime Labour Convention, 2006—reflections on challenges for flag State implementation

This paper begins by providing a brief overview of the International Labour Organization’s Maritime Labour Convention, 2006 (MLC, 2006), noting that this Convention, often called the “Seafarers’ bill of rights”, seeks to achieve both social and labour rights (“decent work”) for seafarers and fair competition (achieving a level-playing field) for shipowners. It has been described as the “fourth pillar” of the international maritime regulatory regime complementing the major International Maritime Organization conventions. The paper provides a brief update on international efforts to achieve the 30/33 formula needed to bring the Convention into force [at present, the tonnage element, 33% has been achieved already with coverage now at 54% of the world fleet (by gross tonnage), with 18 ratifications]. It then explores challenges faced by flag States in connection with capacity to implement the ship inspection and certification system under the MLC, 2006 and other difficulties with respect to legal implementation by the flag States. The paper also comments on some challenges in connection with port State, coastal State and labour-supplying State responsibilities. The paper points out that the MLC, 2006 is a comprehensive code that covers diverse issues and a wider range of both ships and seafarers than previous conventions. It often requires interdepartmental cooperation to implement its requirements at the national level. The paper concludes that, despite the slower pace of ratification in some regions, largely because of the recent economic and other crises, it appears that many actors in the maritime sector are already actively engaged in MLC, 2006 implementation, often ahead of governments. The question is not “if” but “when” the formula will be achieved to allow the MLC, 2006 to enter into force.
Monolithically Patterned Wide–Narrow–Wide All-Graphene Devices

We investigate theoretically the performance advantages of all-graphene nanoribbon field-effect transistors (GNRFETs) whose channel and source/drain (contact) regions are patterned monolithically from a 2-D single sheet of graphene. In our simulated devices, the source/drain and interconnect regions are composed of wide GNR sections that are semimetallic, while the channel regions consist of narrow GNR sections that open semiconducting bandgaps. Our simulation employs a fully atomistic model of the device, contact, and interfacial regions using tight-binding theory. The electronic structures are coupled with a self-consistent 3-D Poisson's equation to capture the nontrivial contact electrostatics, along with a quantum kinetic formulation of transport based on nonequilibrium Green's functions. Although we only consider a specific device geometry, our results establish several general performance advantages of such monolithic devices (besides those related to fabrication and patterning), namely, the improved electrostatics, suppressed short-channel effects, and Ohmic contacts at the narrow-to-wide interfaces.
Counting substructures II: Hypergraphs

For various k-uniform hypergraphs F, we give tight lower bounds on the number of copies of F in a k-uniform hypergraph with a prescribed number of vertices and edges. These are the first such results for hypergraphs, and extend earlier theorems of various authors who proved that there is one copy of F. A sample result is the following: Furedi-Simonovits [11] and independently Keevash-Sudakov [16] settled an old conjecture of Sos [29] by proving that the maximum number of triples in an n vertex triple system (for n sufficiently large) that contains no copy of the Fano plane is p(n)=( 2 ?n/2? )?n/2?+( 2 ?n/2? ?n/2?). We prove that there is an absolute constant c such that if n is sufficiently large and 1 ≤ q ≤ cn 2, then every n vertex triple system with p(n)+q edges contains at least $6q\left( {\left( {_4^{\left\lfloor {n/2} \right\rfloor } } \right) + \left( {\left\lceil {n/2} \right\rceil - 3} \right)\left( {_3^{\left\lfloor {n/2} \right\rfloor } } \right)} \right)$ copies of the Fano plane. This is sharp for q≤n/2---2. Our proofs use the recently proved hypergraph removal lemma and stability results for the corresponding Turan problem.
Optimization of Structures and LJ Parameters of 1-Chloro-1,2,2-trifluorocyclobutane and 1,2-Dichlorohexafluorocyclobutane

The structures and the Lennard-Jones (LJ) parameters of anesthetic 1-chloro-1,2,2-trifluorocyclobutane (F3) and nonimmobilizer 1,2-dichlorohexafluorocyclobutane (F6) were optimized by using ab initio calculations in conjunction with liquid and gas phase molecular dynamics simulations. Geometry optimization of various isomers of F3 and F6 was carried out with MP2/6-311+G(2d,p) that reproduced the experimental pucker angles of the precursors perfluorocyclobutane and cyclobutane more accurately than with B3LYP/6-311+G(2d,p). Frequency calculations were performed to ensure that the optimized structures were at minimums of the potential energy surfaces. The partial atomic charges of F3 and F6 from the Merz−Singh−Kollman MP2/6-311+G(2d,p) calculations and the LJ parameters optimized previously for other halogenated compounds were used to start molecular dynamics simulations. The LJ parameters were then optimized through iterative adjustments to regenerate the heat of vaporization and the densities of F3 and F6 ...
Vitamin A supplementation and morbidity among preschool children in south India.

A randomized, double-blind, placebo-controlled trial was conducted in an ongoing Growth Monitoring Research project in TamilNadu, India, to assess the impact of high-dose vitamin A supplementation on morbidity among mildly to moder- ately malnourished children aged < 3 y. Every 4 mo, the treatment group received 60 mg vitamin A (200 000 IU) whereas the control group received a placebo. Cases of xerophthalmia and severe malnutrition were excluded. Anthropometric measurements and serum retinol determinations were made at baseline and at the end of 1 y. Morbidity data were collected by trained village-level workers throughout the study period by using the weekly recall method. The two groups had similar nutritional status, serum retinol concentrations, age-sex composition, and other sociodemo- graphic indicators at baseline. The mean number of episodes per child-year was 2.62 ± 2.95 and 2.56 ± 2.5 for respiratory illness and 1.9 ± 2.2 and 1.77 ± 1.77 for diarrhea for the vitamin A (n = 309) and placebo (n 274) groups, respectively. The differences in respiratory and diarrheal morbidity between the two groups were not statistically significant and these findings remained un- altered after multivariate analysis in which the effects of age, sex, socioeconomic status, sanitation, etc, were considered. These find- ings are similar to other recent findings and indicate that vitamin A supplementation does not reduce common morbidity in children with mild-to-moderate vitamin A deficiency in areas where access to health care and immunization are good. Am J Clin Nutr 1995;61 :1295-303.
CONFORMATIONAL ANALYSIS OF COPPER(II) 1,4,8,11-TETRAAZACYCLOTETRADECANE MACROCYCLIC SYSTEMS

Abstract A search of the Cambridge Structure Database for all copper (II) complexes with a 1,4,8,11-tetraazacyclotetradecane backbone was conducted. Eighty nine crystal structures were found which were analyzed using an agglomerative, hierarchical, single-link cluster analysis method. The cluster analysis effectively separated the different conformations and configurations of the macrocyclic complexes. Molecular mechanics was used to establish the effect of macrocyclic substituents on the conformations and configurations adopted by the copper(II) macrocyclic complexes.
Life history trait diversity of native freshwater fishes in North America

Freshwater fish diversity is shaped by phylogenetic constraints acting on related taxa and biogeographic constraints operating on regional species pools. In the present study, we use a trait-based approach to examine taxonomic and biogeographic patterns of life history diversity of freshwater fishes in North America (exclusive of Mexico). Multivariate analysis revealed strong support for a tri-lateral continuum model with three end-point strategies defining the equilibrium (low fecundity, high juvenile survivorship), opportunistic (early maturation, low juvenile survivorship), and periodic (late maturation, high fecundity, low juvenile survivorship) life histories. Trait composition and diversity varied greatly between and within major families. Finally, we used occurrence data for large watersheds (n = 350) throughout the United States and Canada to examine geographic patterns of life history variation. Distinct patterns of life history strategies were discernible and deemed congruent with biogeographic processes and selection pressures acting on life history strategies of freshwater fishes throughout North America.
Comparison of PCR, Antigenemia Assay, and Rapid Blood Culture for Detection and Prevention of Cytomegalovirus Disease after Lung Transplantation

The goal of this study was to evaluate serial cytomegalovirus (CMV) blood culture, antigenemia testing, and qualitative and quantitative plasma CMV PCR for their ability to predict CMV disease and thus to direct preemptive therapy after lung transplantation. Forty-one patients provided 414 samples for blood culture, 290 samples for antigenemia testing, and 432 samples for PCR. Seven patients developed 11 episodes of CMV disease. CMV PCR had sensitivity, specificity, and positive predictive and negative predictive values of 79, 99, 84, and 99%, respectively, compared with 48, 99, 85, and 98%, respectively, for antigenemia testing, and 8, 100, 100, and 97%, respectively, for culture. Only quantitative CMV PCR correlated with disease stage: asymptomatic patients had a mean of 1,500 CMV DNA copies/ml, whereas patients who developed CMV disease had 5,087 copies/ml 12 to 4 weeks before symptoms and 32,000 copies/ml at diagnosis. Furthermore, CMV PCR-measured DNA increased 5- to 10-fold immediately preceding symptoms. PCR and antigenemia test values decreased with anti-CMV therapy. CMV DNA (as detected by PCR), but not antigenemia, persisted in patients who later developed recurrent CMV disease. The data indicate that lung transplant recipients will benefit from monitoring of CMV disease by plasma CMV PCR.
Evaluation of the safety and efficacy of deep sedation for electrophysiology procedures administered in the absence of an anesthetist

UNLABELLED Several procedures performed in the electrophysiology laboratory (EP lab) require surgical manipulation and are lengthy. Patients undergoing such procedures usually receive general anesthesia or deep sedation administered by an anesthesiologist. In 536 consecutive procedures performed in the EP lab, we assessed the safety and efficacy of deep sedation administered under the direction of an electrophysiologist and in the absence of an anesthetist. Patients were monitored with pulse oximetry, noninvasive blood pressure recordings, and continuous ECGs. The level of consciousness and vital signs were evaluated at 5-minute intervals. Deep sedation was induced in 260 patients using midazolam, phenergan, and meperidine, then maintained with intermittent dosing of meperidine at the following mean doses: midazolam 0.031 +/- 0.024 mg/kg; phenergan 0.314 +/- 0.179 mg/kg; and meperidine 0.391 +/- 0.167 mg/kg per hour. In the remaining 276 patients, deep sedation was induced with midazolam and fentanyl and maintained with a continuous infusion of fentanyl at a mean dose of 2.054 +/- 1.43 micrograms/kg per hour. Fourteen patients experienced a transient reduction in oxygen saturation that was readily reversed following administration of naloxone. An additional 11 patients desaturated secondary to partial airway obstruction, which resolved after repositioning the head and neck. Fourteen patients experienced hypotension with fentanyl. All but one returned to baseline blood pressures following an infusion of normal saline. No patient required intubation and no death occurred. Only three patients had recollection of periprocedure events. No patient remembered experiencing pain with the procedure. Hospital stays were not prolonged as a result of the sedation used. IN CONCLUSION (1) deep sedation during EP procedures can be administered safely under the guidance of the electrophysiologist without an anesthetist present; (2) the drugs used should be readily reversible in case of respiratory depression; and (3) this approach may reduce the overall cost of the procedures in the EP lab, maintaining adequate patient comfort.
A refined monoclinic structure for a variety of “hydrohematite”

In ferruginous soils, nano- to microscale hematite (α-Fe 2 O 3 ) plays a central role in redox processes and contaminant cycling. Hematite is known to incorporate structural OH − and water, and the requisite charge balance is achieved by iron vacancies. Prior researchers have suggested that the defective hematite structures form unique phases called “protohematite” and “hydrohematite.” Infrared and Raman spectroscopic studies have assigned a lower-symmetry space group to “hydrohematite” ( R 3 c ) relative to that of stoichiometric hematite ( R 3 c ). However, the existence and structure of these phases have been contentious, largely due to the lack of in situ X-ray diffraction data Here we present a new structure refinement for “hydrohematite” precipitated hydrothermally at 200 °C in a monoclinic space group ( I 2/ a ) using time-resolved synchrotron X-ray diffraction (TR-XRD) data collected during the in situ hydrothermal precipitation of akaganeite and its transformation to stoichiometric hematite. Distinct peak splitting was observed in the “hydrohematite” diffraction patterns, indicating a violation of the threefold rotational symmetry. A monoclinic unit cell with parameters of a = 7.3951(10), b = 5.0117(5), c = 5.4417(7) A, β = 95.666(5)° provided a good fit and significant reduction in χ 2 and R wp relative to space group R 3 c . Rietveld analyses revealed that water concentrations in the first-formed crystals of “hydrohematite” were comparable to water contents of akaganeite and goethite. Thus, the hydrothermal transformation of akaganeite to “hydrohematite” is promoted not by dehydration but by reconstruction of the oxygen framework.
A Goal for Reform: Make Elections Worth Stealing

Election reforms have attracted substantial attention since the troubled elections of 2000. Some address problems in the administration of elections. Others aim to regulate the conduct of elected officials and lobbyists. A third category affects the structure by which elections are conducted. It is not clear whether the same over-arching problem motivates interest in these reforms. One common theme may be that public confidence in representation suffers as a result of actual or perceived deficiencies in the conduct of elections and elected officials. The failure to count votes accurately, the fact that eligible voters find they are unable to vote, the inability of minor parties to access ballots, revelations of scandalous relations between representatives and lobbyists, the power of wealthy donors, the lack of “civility” in political discourse, the uncompetitive nature of many elections, may all somehow act together to erode public trust, and reduce participation and engagement with representative democracy.
Cigarette Smoke Components Induce Matrix Metalloproteinase-1 in Aortic Endothelial Cells through Inhibition of mTOR Signaling

Smoking is a major risk factor for heart disease, but the molecular effects of cigarette smoke on vascular cells are poorly understood. In this study, we demonstrate that matrix metalloproteinase-1 (MMP-1), a collagenase expressed in atherosclerosis and aneurysms but not in the normal vessel wall, is induced in the aortic endothelium of rabbits exposed to cigarette smoke. In vitro cigarette smoke extract (CSE) and one of its components, acrolein, inhibit the mammalian target of rapamycin (mTOR)/p70S6K pathway in human endothelial cells, and chemical inhibition of this pathway by rapamycin resulted in elevated MMP-1. Moreover, the tissue inhibitor of metalloproteases-3 (TIMP-3), a major regulator of angiogenesis, is significantly downregulated in aortic endothelial cells treated with CSE, acrolein, or rapamycin. These data indicate that inhibition of mTOR by cigarette smoke components is a key event in the modulation of endothelial MMP-1 and TIMP-3 expression. Our study suggests that circulating smoke components, including acrolein, contribute to vascular diseases through enhanced MMP-1 and decreased TIMP-3 secretion in the endothelium, potentially leading to impaired angiogenesis, matrix disruption, and vessel injury.
Chemoenzymatic synthesis and lectin array characterization of a class of N-glycan clusters.

N-glycans are major components of many glycoproteins. These sugar moieties are frequently involved in important physiological and disease processes via their interactions with a variety of glycan-binding proteins (GBP). Clustering effect is an important feature in many glycan-lectin interactions. We describe in this paper a chemoenzymatic synthesis of novel N-glycan clusters using a tandem endoglycosidase-catalyzed transglycosylation. It was found that the internal β-1,2-linked GlcNAc moieties in the N-glycan core, once exposed in the non-reducing terminus, was able to serve as acceptors for transglycosylation catalyzed by Endo-A and EndoM-N175A. This efficient chemoenzymatic method allows a quick extension of the sugar chains to form a class of glycan clusters in which sugar residues are all connected by native glycosidic linkages found in natural N-glycans. In addition, a discriminative enzymatic reaction at the two GlcNAc residues could be fulfilled to afford novel hybrid clusters. Lectin microarray studies revealed unusual properties in glyco-epitope expression by this panel of structurally well-defined synthetic N-glycans. These new compounds are likely valuable for functional glycomics studies to unveil new functions of both glycans and carbohydrate-binding proteins.
Animating a continuous family of two-site Voronoi diagrams (and a proof of a bound on the number of regions)

A two-site distance function defines a "distance" measure from a point to a pair of points; mathematically, it is a mapping D:R2×(R2×R2)R+. A Voronoi diagram for a two-site distance function D and a set S of planar point sites has a region V (p, q) for each pair of sites p,q-S , where V(p,q) is defined as the set of all points in the plane "closer" to (p, q)"under distance function D"than to any other pair of sites in S. Two-site distance functions and their Voronoi diagrams have been explored by Barequet et al. (2002) and animated by Barequet et al. (2001), who givethe complexity of the Voronoi diagram for the two-site sum function (among others), and leave as an open question the complexity of the diagram for the two-site perimeter function. In this video, we introduce and animate a new continuous family of two-site distance functions Dc defined for any constant ce-1. This family includes both the sum and perimeter distance functions, providing a unifying model. We also present and animate in this video a new proof that the perimeter function Voronoi diagram has O(n) non-empty regions. The proof generalizes to any function in the Dc family when ce0. The animation also shows how the various functions in the family relate to one another.
Identification of osteopontin-dependent signaling pathways in a mouse model of human breast cancer

Background Osteopontin (OPN) is a secreted phosphoprotein which functions as a cell attachment protein and cytokine that signals through two cell adhesion molecules, αvβ3-integrin and CD44, to regulate cancer growth and metastasis. However, the signaling pathways associated with OPN have not been extensively characterized. In an in vivo xenograft model of MDA-MB-231 human breast cancer, we have previously demonstrated that ablation of circulating OPN with an RNA aptamer blocks interaction with its cell surface receptors to significantly inhibit adhesion, migration and invasion in vitro and local progression and distant metastases.
Brownfields and Greenfields: The Intersection of Sustainable Development and Environmental Stewardship

The recent growth of urban brownfield redevelopment and greenfield protection initiatives is a positive indicator of the redirected priorities of the public and private sectors to restore and regen...
Dynamics of propranolol dosing schedules

Kinetic and dynamic data from 27 healthy male subjects were evaluated in a double-blind, randomized, double-crossover study to test the hypothesis that 180 mg/day propranolol twice and three times a day would provide much the same plasma levels and β1-blockade. The data indicate that propranolol twice rather than three times a day should be favored when β1-blockade is needed in therapy. The dynamic efficacy of the two schedules was the same and maximum concentration, AUC0–24, and 0-hr plasma propranolol values were higher after twice-than after three-times-daily dosing. The degree of β1-blockade (reduction in exercise tachycardia) was much the same on both dosing regimens at trough concentrations. These data indicate that both twice- and three-times-a-day dosing schedules provide well-sustained 24-hr β-blockade and are probably interchangeable for therapeutic purposes. Clinical Pharmacology and Therapeutics (1983) 34, 440–447; doi:10.1038/clpt.1983.195
Mars Science Laboratory Rover System Thermal Test

On November 26, 2011, NASA launched a large (900 kg) rover as part of the Mars Science Laboratory (MSL) mission to Mars. The MSL rover is scheduled to land on Mars on August 5, 2012. Prior to launch, the Rover was successfully operated in simulated mission extreme environments during a 16-day long Rover System Thermal Test (STT). This paper describes the MSL Rover STT, test planning, test execution, test results, thermal model correlation and flight predictions. The rover was tested in the JPL 25-Foot Diameter Space Simulator Facility at the Jet Propulsion Laboratory (JPL). The Rover operated in simulated Cruise (vacuum) and Mars Surface environments (8 Torr nitrogen gas) with mission extreme hot and cold boundary conditions. A Xenon lamp solar simulator was used to impose simulated solar loads on the rover during a bounding hot case and during a simulated Mars diurnal test case. All thermal hardware was exercised and performed nominally. The Rover Heat Rejection System, a liquid-phase fluid loop used to transport heat in and out of the electronics boxes inside the rover chassis, performed better than predicted. Steady state and transient data were collected to allow correlation of analytical thermal models. These thermal models were subsequently used to predict rover thermal performance for the MSL Gale Crater landing site. Models predict that critical hardware temperatures will be maintained within allowable flight limits over the entire 669 Sol surface mission.
On the Threshold Effect in FM Data Systems

The threshold noise performance of a limiter-discriminator, with input signal uniformly distributed over the full scale frequency deviation range, is analyzed in terms of an evaluation criterion which specifies the system resolution (\pm R) and the probability ( P ) with which output noise exceeds that resolution. This criterion, meaningful above and below threshold, forms a basis for a precise definition of threshold, the location of which is determined equally precisely and found to lie between 6 dB and 10 dB input signal-to-noise ratio (SNR) for the range of ( R, P ) values considered. The channel efficiency of FM relative to Shannon's law is also determined approximately in light of this criterion, from which the ultimate FM threshold follows.
A Re-examination of Query Expansion Using Lexical Resources

Query expansion is an effective technique to improve the performance of information retrieval systems. Although hand-crafted lexical resources, such as WordNet, could provide more reliable related terms, previous studies showed that query expansion using only WordNet leads to very limited performance improvement. One of the main challenges is how to assign appropriate weights to expanded terms. In this paper, we re-examine this problem using recently proposed axiomatic approaches and find that, with appropriate term weighting strategy, we are able to exploit the information from lexical resources to significantly improve the retrieval performance. Our empirical results on six TREC collections show that query expansion using only hand-crafted lexical resources leads to significant performance improvement. The performance can be further improved if the proposed method is combined with query expansion using co-occurrence-based resources.