cssi/SciSciGPT-SciSciNet huggingface dataset:
Magnesium intake is related to improved insulin homeostasis in the framingham offspring cohort.

Objective: Higher dietary intake of magnesium may protect against development of type 2 diabetes. The aim of this study was to examine the association between dietary magnesium intake and metabolic risk factors for diabetes.Methods: We examined cross-sectional associations between magnesium intake and fasting glucose and insulin, 2-hour post-challenge plasma glucose and insulin, and insulin resistance assessed by the homeostasis model (HOMA-IR) in 1223 men and 1485 women without diabetes from the Framingham Offspring cohort. Magnesium intake was assessed by a food frequency questionnaire and magnesium intake was categorized into quintile categories. Geometric mean insulin, glucose, 2-hour post challenge plasma glucose and insulin concentrations and HOMA-IR were estimated across quintile categories of magnesium intake using Generalized Linear Models.Results: After adjustment for potential confounding factors, magnesium intake was inversely associated with fasting insulin (mean: 29.9 vs 26.7 μU/mL in the lo...
Periaqueductal gray matter projections to midline and intralaminar thalamic nuclei of the rat.

The periaqueductal gray matter (PAG) projections to the intralaminar and midline thalamic nuclei were examined in rats. Phaseolus vulgaris-leucoagglutinin (PHA-L) was injected in discrete regions of the PAG, and axonal labeling was examined in the thalamus. PHA-L was also placed into the dorsal raphe nuclei or nucleus of Darkschewitsch and interstitial nucleus of Cajal as controls. In a separate group of rats, the retrograde tracer cholera toxin beta-subunit (CTb) was injected into one of the intralaminar thalamic nuclei-lateral parafascicular, medial parafascicular, central lateral (CL), paracentral (PC), or central medial nucleus-or one of the midline thalamic nuclei-paraventricular (PVT), intermediodorsal (IMD), mediodorsal, paratenial, rhomboid (Rh), reuniens (Re), or caudal ventral medial (VMc) nucleus. The distribution of CTb labeled neurons in the PAG was then mapped. All PAG regions (the four columns of the caudal two-thirds of the PAG plus rostral PAG) and the precommissural nucleus projected to the rostral PVT, IMD, and CL. The ventrolateral, lateral, and rostral PAG provided additional inputs to most of the other intralaminar and midline thalamic nuclei. PAG inputs to the VMc originated from the rostral and ventrolateral PAG areas. In addition, the lateral and rostral PAG projected to the zona incerta. No evidence was found for a PAG input to the ventroposterior lateral parvicellular, ventroposterior medial parvicellular, caudal PC, oval paracentral, and reticular thalamic nuclei. PAG --> thalamic circuits may modulate autonomic-, nociceptive-, and behavior-related forebrain circuits associated with defense and emotional responses.
JAPANESE INDUSTRIAL POLICY IN AIRCRAFT MANUFACTURING

Marketing and corporate risk‐taking are always included as elements of industrial competitiveness and yet discussions of industrial policy are strangely silent on these important determinants of firm performance. The inability of Japanese industrial policy to develop these skills has been an important factor in determining the competitive position of the Japanese commercial airplane manufacturing industry. In this industry where domestic demand was not guaranteed, and where the Japanese competitors were not prepared to assume the risk‐taking position common to successful foreign competitors, Japanese industrial policy was unable to match its earlier success in basic industries.
Lithium-Ion Battery Electrode Inspection Using Flash Thermography

Pulse thermography was used to experimentally evaluate lithium-ion battery electrode quality. Lab manufactured electrodes with gross defects, thickness variation, and composition variation all were detectable with this method. Thickness variation was shown to have a one to one ratio percent change in thickness to percent change in thermal response. A thickness difference of 4 μm (4 % of total) was detectable with the method. Lab electrodes were compared with commercial electrodes with comparable results. Both types of electrodes showed a significant thickness oscillation that has not previously been reported regarding lithium-ion battery electrodes.
On the admissibility of some sequential confidence intervals for the negative exponential location parameter

With reference to a general class of sequential procedures, this paper shows the admissibility of fixed-width confidence intervals, based on the smallest sample observation, for the location parameter of a negative exponential population with an unknown scale parameter.
Response of Hosts of Varying Susceptibility to a Recombinant Baculovirus Insecticide in the Field

Abstract In an attempt to improve the effectiveness of nucleopolyhedroviruses (NPV) as bioinsecticides of lepidopteran pests, the NPV of Autographa californica (AcMNPV) has been genetically modified to include a gene that expresses an insect-selective scorpion toxin, AaHIT. In a field trial, we compared the response of a highly susceptible ‘target’ host ( Trichoplusia ni ) and a representative less susceptible species ( Mamestra brassicae ), following spraying with wild-type AcMNPV and the genetically modified virus. Mortality and therefore risk of infection were significantly lower in the less susceptible species but did not differ between the wild-type and the recombinant viruses. Speed of kill was consistently faster in T. ni infected with the recombinant virus for samples collected 1, 3, and 5 days following spray application. The results for M. brassicae were more variable; time to death induced by both viruses was longer in M. brassicae than in T. ni but the genetically modified virus acted faster only in larvae taken 3 and 5 days following spraying. This contrasts with laboratory assays in which the recombinant virus took longer than the wild-type virus to kill M. brassicae. The results demonstrate that there are differences in virus productivity, distribution, and timing of virus release when two hosts with different susceptibilities are treated with wild-type and recombinant baculoviruses, which will impact on further rounds of virus replication. Thus, the effects of recombinant baculoviruses on less susceptible, potentially nontarget, hosts are not likely to be easy to predict, and they highlight the need for both more information on the behavior of baculoviruses in hosts of varying susceptibility and further studies on the impact of these factors on secondary transmission.
Exchange kinetic energy, contragradience, and chemical binding

Abstract The energy components of the G1 wavefunction for H 2 are carefully analyzed. It is found that the binding is dominated by the exchange part of the kinetic energy and that this term is dominant because of the contragradience of the orbitals in the bond region.
On the rank of apparition of composite N in the Lehmer sequences

Abstract The rank of apparition of a number N in an underlying recursively defined Lehmer sequence is the index of the first term that contains N as a divisor. In this paper, we state the conjecture that if ( N ± 1 ) / 2 is the rank of apparition of N then N is prime. Evidence of its truth is supplied by demonstrating the impossibility of ( N ± 1 ) / 2 as being the rank of apparition of any composite number defined by the product of distinct odd primes. The conjecture, if true, will provide an extension to the primality result of D. Lehmer which states that if N ± 1 is the rank of apparition of N then N is prime.
Stem Cell Response to Spatially and Temporally Displayed and Reversible Surface Topography

The dynamic alignment of cells and matrix is critical in many biological processes, including during tissue development and in the progression of a variety of diseases; yet, nearly all in vitro models are static. Thus, it is of great interest to temporally and spatially manipulate cellular alignment to better understand and develop strategies to control these biological processes. Here, strain-responsive buckling patterns on PDMS substrates are used to dynamically and spatially control human mesenchymal stem cell (hMSC) organization. The results indicate that cellular alignment and pattern recognition are strongly diminished with culture time, which can be overcome by limiting cellular proliferation. Preferential alignment of the hMSCs is completely eliminated after the topography switch from patterned to flat, and can be reversibly repeated for at least 8 cycles. The hMSCs are responsive to dynamic changes in pattern size, where the distribution of the cells with preferential alignment increase with increasing pattern amplitude and decreasing wavelength. Furthermore, by introducing a biaxial stretching system, dynamic control is introduced over the cellular orientation angle and order, and by controlling the UV-ozone exposure of the PDMS, the topographical features can be spatially patterned.
Isolation of sterol mutants inChlamydomonas reinhardi: Chromatographic analyses

Several sterol mutants ofChlamydomonas reinhardi were isolated by selecting for single colonies resistant to the polyene antibiotic, nystatin. The sterol profiles of three isolates-KD7, KD16, and KD21-as well as a wild type strain (137C) were determined by gas liquid chromatography and mass spectrometry. The wild type strain contained ergosterol (C28-5,7,22-triene) as the predominant sterol, with smaller amounts of a C28-5,7-diene, a C28-7-ene, and C-24 ethyl analogs of these three sterols. The three mutants had altered sterol composition, but none required exogenous sterol for growth. KD7 contained a C28-5,7,22,25-tetraene, a C28-5,7,25-triene, a C28-7,25-diene, and three C-24 ethyl analogs. The lesion in KD7 is apparently an inability to reduce the C-25 double bond required for the biosynthesis of ergosterol and an ethyl analog. The predominant sterols accumulated by KD16 and KD21 were a C28-5,7-diene, a C28-7-ene, and C-24 ethyl versions of these two sterols, suggesting that these strains are 22(23)-desaturase mutants.
Microvascular thermal equilibration in rat spinotrapezius muscle.

The current study investigates heat exchange in the thermally significant countercurrent paired vessels of the rat spinotrapezius muscle. Detailed tissue surface temperatures under normal (after the microvascular surgery) and pharmacologically vasodilated states were measured using high-resolution infrared thermography. During vasodilation, a measurable thermal disturbance was observed above the first-order feeding vessel pair. The measured tissue temperatures were compared with those predicted by modifying the theoretical model for two-dimensional muscle preparations given by Zhu et al. (Zhu, L., D. E. Lemons, and S. Weinbaum. Ann. Biomed. Eng. 24:109–123, 1996). They were found in good agreement. The Weinbaum–Jiji keff theory (Weinbaum, S., and L. M. Jiji. J. Biomech. Eng. 107:131–139, 1985) for heat exchange between the paired vessels and their surrounding tissue was also examined in this muscle. A close agreement was obtained between the theoretically predicted keff and the measured value calculated using a fin approximation for the tissue layer. This experimental study revealed for the first time the nonequilibration between blood vessels and the surrounding tissue, where the enhancement in keff due to the incomplete countercurrent heat exchange is comparable to the tissue axial conduction. © 1999 Biomedical Engineering Society.
Models of travel demand with endogenous preference change and heterogeneous agents

In the literatures of regional science, urban economics, and urban development planning, a working assumption is that individuals respond to incentives and regulations, given their preferences. Models for planning and policy analyses are used to consider what might occur if the incentives or regulations were different. In these models, however, preferences are usually assumed to be given and stable, and agents are usually assumed to be homogeneous. This paper focuses on the implications of making preferences in models of policy implementation endogenously determined and time varying heterogeneous agents. We consider first the recent literature on intertemporal choice and preference change, which cuts across many disciplines, and more briefly the literature on norm-regarding behavior. We then elaborate a simple model of transportation demand—from a static to a dynamic orientation, from fixed and exogenously given preferences of strictly self-regarding agents to endogenously determined and policy-induced preferences of heterogeneous agents—and illustrate its characteristics with simple numerical examples.
Restoration of MRI Data for Field Nonuniformities using High Order Neighborhood Statistics

MRI at high magnetic fields (> 3.0 T ) is complicated by strong inhomogeneous radio-frequency fields, sometimes termed the “bias field”. These lead to nonuniformity of image intensity, greatly complicating further analysis such as registration and segmentation. Existing methods for bias field correction are effective for 1.5 T or 3.0 T MRI, but are not completely satisfactory for higher field data. This paper develops an effective bias field correction for high field MRI based on the assumption that the nonuniformity is smoothly varying in space. Also, nonuniformity is quantified and unmixed using high order neighborhood statistics of intensity cooccurrences. They are computed within spherical windows of limited size over the entire image. The restoration is iterative and makes use of a novel stable stopping criterion that depends on the scaled entropy of the cooccurrence statistics, which is a non monotonic function of the iterations; the Shannon entropy of the cooccurrence statistics normalized to the effective dynamic range of the image. The algorithm restores whole head data, is robust to intense nonuniformities present in high field acquisitions, and is robust to variations in anatomy. This algorithm significantly improves bias field correction in comparison to N3 on phantom 1.5 T head data and high field 4 T human head data.
SPECTROFLUOROMETRIC DETERMINATION OF Mg-PROTOPORPHYRIN MONOESTER AND LONGER WAVELENGTH METALLOPORPHYRINS IN THE PRESENCE OF Zn-PROTOPORPHYRIN†

Abstract. Greening tissues accumulate Mg-protoporphyrin monoester and a group of metalloporphyrins that exhibit fluorescence emission and excitation properties which are red-shifted with respect to Mg-protoporphyrin monoester. These metalloporphyrins are collectively termed longer wavelength metalloporphyrins and are presumed to be metabolic intermediates between Mg-protoporphyrin monoester (MPE) and protochlorophyllide. The longer wavelength metalloporphyrins, together with Mg-protoporphyrin monoester, are referred to as the MPE-equivalent. During the study of the biosynthesis of the components of the MPE-equivalent and the study of their conversion to protochlorophyllide in vitro, it was observed that Zn-protoporphyrin and its monoester were also formed. The latter compounds interfered with the determination of the MPE-equivalent. Simultaneous equations were derived and solved to yield an equation which permitted the determination of the amount of MPE-equivalent in the presence of Zn-protoporphyrins from the fluorescence emission spectrum of the mixture. Such determinations were made without prior segregation of the metalloporphyrins.
Capabilities of Ultrasonic Phased Arrays for Far-Side Examinations of Austenitic Stainless Steel Piping Welds

A study was conducted to assess the ability of advanced ultrasonic techniques to detect and accurately determine the size of flaws from the far-side of wrought austenitic piping welds. Far-side inspections of nuclear system austenitic piping welds are currently performed on a “best effort” basis and do not conform to ASME Code Section XI Appendix VIII performance demonstration requirements for near side inspection. For this study, four circumferential welds in 610mm (24inch) diameter, 36mm (1.42inch) thick ASTM A-358, Grade 304 vintage austenitic stainless steel pipe were examined. The welds were fabricated with varied welding parameters; both horizontal and vertical pipe orientations were used, with air and water backing, to simulate field welding conditions. A series of saw cuts, electro-discharge machined (EDM) notches, and implanted fatigue cracks were placed into the heat affected zones of the welds. The saw cuts and notches ranged in depth from 7.5% to 28.4% through-wall. The implanted cracks ranged in depth from 5% through-wall to 64% through-wall. The welds were examined with phased array technology at 2.0 MHz, and compared to conventional ultrasonic techniques as a baseline. The examinations showed that phased-array methods were able to detect and accurately length-size, but not depth size, the notches and flaws through the welds. The ultrasonic results were insensitive to the different welding techniques used in each weld.Copyright © 2006 by ASME
On Spectrum-Efficient Green Optical Backbone Networks

We propose an orthogonal frequency division multiplexing (OFDM) based backbone optical network design. We focus on minimizing the total energy consumption of the network i.e., to make the network green. OFDM is a promising technology for next- generation optical networks with per-wavelength capacities higher than or equal to 100 Gbps. In addition, it can support heterogeneity in network traffic by having flexible bandwidth allocation per wavelength. The flexibility comes through the multiple subcarriers in an OFDM signal which can be modulated with the client data signals. Another paradigm for supporting traffic heterogeneity and high bandwidth demands is mixed-line-rate (MLR) networks where wavelengths can have discrete capacities of 10/40/100 Gbps which are single carrier based. In this study, we compare the energy efficiency of an OFDM-based network versus a MLR network. Our results show that OFDM outperforms MLR in terms of energy efficiency.
Impact of Markov Random Field optimizer on MRI-based tissue segmentation in the aging brain

Automatically segmenting brain magnetic resonance images into grey matter, white matter, and cerebrospinal fluid compartments is a fundamentally important neuroimaging problem whose difficulty is heightened in the presence of aging and neurodegenerative disease. Current methods overlap greatly in terms of identifiable algorithmic components, and the impact of specific components on performance is generally unclear in important real-world scenarios involving serial scanning, multiple scanners, and neurodegenerative disease. Therefore we evaluated the impact that one such component, the Markov Random Field (MRF) optimizer that encourages spatially-smooth tissue labelings, has on brain tissue segmentation performance. Two challenging elderly data sets were used to test segmentation consistency across scanners and biological plausibility of tissue change estimates; and a simulated young brain data set was used to test accuracy against ground truth. Belief propagation (BP) and graph cuts (GC), used as the MRF optimizer component of a standardized segmentation system, provide high segmentation performance on aggregate that is competitive with end-to-end systems provided by SPM and FSL (FAST) as well as the more traditional MRF optimizer iterated conditional modes (ICM). However, the relative performance of each method varied strongly by performance criterion and differed between young and old brains. The findings emphasize the unique difficulties involved in segmenting the aging brain, and suggest that optimal algorithm components may depend in part on performance criteria.
Stability of the solid-liquid interface of semi-transparent materials

Abstract The pertinent features of the mathematical formulation for heat flow by coupled radiation and conduction are reviewed with particular emphasis on its relationship to the physical process of crystal growth in semi-transparent systems. The results of numerical solution to the resultant integro-differential equations are given and are discussed relative to the model. Regarding the question of interface stability, the most important conclusion of these calculations is that the temperature gradient at the interface is invariably steeper in combined radiative and conductive systems as compared to the pure conduction case. As a result, it is concluded that an interface is, in fact, stabilized during crystal growth in the presence of radiative heat transfer relative to the pure conductive (opaque) case.
Genetic variation in marine fishes as a test of the niche-variation hypothesis

SINCE the discovery of large and variable amounts of protein polymorphism in natural populations1, biologists have attempted to determine what, if any, biological significance is associated with this particular form of phenotypic variation. Many population geneticists and ecologists2–5 have adopted a selectionist point of view which states that allelic diversity is a strategy for increasing population fitness in a temporally and spatially heterogeneous habitat. This hypothesis, known as the “nichevariation hypothesis”, predicts a positive correlation between the protein polymorphism and morphological variation in a population and the relative heterogeneity of the most relevant physical (for example, temperature) and biological (for example, food and competition) variables of the habitat. The basic assumption underlying this hypothesis is that the presence of more than one variant of a given protein broadens the tolerance limits or the optimal functioning range of the structures and/or reactions associated with the protein. For example, the presence of multiple forms of an enzyme, each with a different thermal optimum, may broaden the thermal tolerance range of an ectothermic (poikilothermic; cold blooded) organism6.
Mitochondrial pathobiology in ALS

Amyotrophic lateral sclerosis (ALS) is the third most common human adult-onset neurodegenerative disease. Some forms of ALS are inherited, and disease-causing genes have been identified. Nevertheless, the mechanisms of neurodegeneration in ALS are unresolved. Genetic, biochemical, and morphological analyses of human ALS as well as cell and animal models of ALS reveal that mitochondria could have roles in this neurodegeneration. The varied functions and properties of mitochondria might render subsets of selectively vulnerable neurons intrinsically susceptible to cellular aging and stress and overlying genetic variations. Changes occur in mitochondrial respiratory chain enzymes and mitochondrial programmed cell death proteins in ALS. Transgenic mouse models of ALS reveal possible principles governing the biology of neurodegeneration that implicate mitochondria and the mitochondrial permeability transition pore. This paper reviews how mitochondrial pathobiology might contribute to the mechanisms of neurodegeneration in ALS.
Assessment of Hybrid RANS/LES Turbulence Models for Aeroacoustics Applications

Predicting the noise from aircraft with exposed landing gear remains a challenging problem for the aeroacoustics community. Although computational fluid dynamics (CFD) has shown promise as a technique that could produce high-fidelity flow solutions, generating grids that can resolve the pertinent physics around complex configurations can be very challenging. Structured grids are often impractical for such configurations. Unstructured grids offer a path forward for simulating complex configurations. However, few unstructured grid codes have been thoroughly tested for unsteady flow problems in the manner needed for aeroacoustic prediction. A widely used unstructured grid code, FUN3D, is examined for resolving the near field in unsteady flow problems. Although the ultimate goal is to compute the flow around complex geometries such as the landing gear, simpler problems that include some of the relevant physics, and are easily amenable to the structured grid approaches are used for testing the unstructured grid approach. The test cases chosen for this study correspond to the experimental work on single and tandem cylinders conducted in the Basic Aerodynamic Research Tunnel (BART) and the Quiet Flow Facility (QFF) at NASA Langley Research Center. These configurations offer an excellent opportunity to assess the performance of hybrid RANS/LES turbulence models that transition from RANS in unresolved regions near solid bodies to LES in the outer flow field. Several of these models have been implemented and tested in both structured and unstructured grid codes to evaluate their dependence on the solver and mesh type. Comparison of FUN3D solutions with experimental data and numerical solutions from a structured grid flow solver are found to be encouraging.
Crystal structure of the eukaryotic origin recognition complex

Initiation of cellular DNA replication is tightly controlled to sustain genomic integrity. In eukaryotes, the heterohexameric origin recognition complex (ORC) is essential for coordinating replication onset. Here we describe the crystal structure of Drosophila ORC at 3.5 A resolution, showing that the 270 kilodalton initiator core complex comprises a two-layered notched ring in which a collar of winged-helix domains from the Orc1–5 subunits sits atop a layer of AAA+ (ATPases associated with a variety of cellular activities) folds. Although canonical inter-AAA+ domain interactions exist between four of the six ORC subunits, unanticipated features are also evident. These include highly interdigitated domain-swapping interactions between the winged-helix folds and AAA+ modules of neighbouring protomers, and a quasi-spiral arrangement of DNA binding elements that circumnavigate an approximately 20 A wide channel in the centre of the complex. Comparative analyses indicate that ORC encircles DNA, using its winged-helix domain face to engage the mini-chromosome maintenance 2–7 (MCM2–7) complex during replicative helicase loading; however, an observed out-of-plane rotation of more than 90° for the Orc1 AAA+ domain disrupts interactions with catalytic amino acids in Orc4, narrowing and sealing off entry into the central channel. Prima facie, our data indicate that Drosophila ORC can switch between active and autoinhibited conformations, suggesting a novel means for cell cycle and/or developmental control of ORC functions. The crystal structure of the heterohexameric origin recognition complex (ORC), essential for coordinating DNA replication onset in eukaryotes, is resolved at 3.5 A resolution. Eukaryotic organisms use a six-subunit DNA binding complex — the origin recognition complex (ORC) — to initiate DNA replication. James Berger and colleagues have solved the structure of this 270 kDa complex at 3.5 A resolution. The notched ring structure of the ORC would be able to encircle duplex DNA, and the domain face that engages the mini-chromosome maintenance 2–7 (MCM2–7) helicase complex is identified. The position of the Orc1 subunit suggests how this subunit may regulate an autoinhibited state of the complex, allowing initiation to be responsive to cell cycle or developmental cues.
PET versus PEN: what difference can a ring make?

Abstract Poly(ethylene terephthalate) (PET) and poly(ethylene 2,6-naphthalate) (PEN) are structurally related polyesters. In each polymer, the ethylene glycol diesters are separated by rigid rings and are attached to the 1,4-positions of the phenyl and the 2,6-positions of the naphthyl rings in PET and PEN, respectively. Because neighboring ethylene glycol units of each polyester are separated by phenyl or naphthyl rings, their conformations are independent of each other. As a consequence, their RIS conformational models should be identical, with the same populations of trans, gauche +, and gauche− conformations about the –O–CH2–, –CH2–CH2–, and –CH2–O– bonds. This means that PET and PEN are equally flexible as judged by their conformational partition functions. However, because they differ geometrically, properties such as the mean-square end-to-end distance (〈r2〉0) or characteristic ratio (Cr=〈r2〉0/n〈l2〉), though averaged over identical conformations, are not expected to be coincident. The terephthaloyl portion of PET can be considered to consist of the , the –C1⋯C4–, and bonds, which are collinear and only the conformations about the carbonyl carbon to phenyl ring carbon bonds may be altered. This results in the terephthaloyl unit acting as a freely rotating link in both the statistical and dynamic senses. In the naphthaloyl residue, on the other hand, the carbonyl carbon to C2 and C6 to carbonyl carbon bonds are connected to a collinear, non-rotatable virtual bond between C2 and C5 and to the non-collinear, non-rotatable real bond between C5 and C6, respectively. These geometrical differences between PET and PEN result in distinctly different values for properties like 〈r2〉0 and Cr, even though they are averaged over the same conformational populations. Additionally, volumes occupied by their segments when confined to extended conformations and interconversions between these extended conformers were found to be particularly sensitive to the geometrical distinctions between PET and PEN and several differences in their physical properties are discussed in this context.
Perceptions of attention deficit hyperactivity disorder and its treatment among children and adolescents

Little is known about how children and adolescents conceptualize psychiatric disorders and psychiatric treatment. In the current study, children and adolescents diagnosed with Attention Deficit Hyperactivity Disorder (ADHD) were interviewed about their understanding of ADHD and the medication used to treat their disorder. The participants were all taking Ritalin and ranged in age from 5 to 16 years. With increasing age, children improved in their ability to name their condition and the medication. Latency-aged children often did not perceive Ritalin as helpful while adolescents recognized some value in taking medication. Some of the adolescents were also able to describe medication side effects. The implications of these findings for patient education are discussed.
Effect of Cortisone and Thyroxine on Aromatic Amino Acid Decarboxylation

The decarboxylation of o-tyrosine and 5-hydroxytryptophan has been studied in tissue homogenates of different organs of both normal and pyridoxinedeficient rats. In pyridoxine-supplemented rats, the apodecarboxylase of liver and brain was more saturated with coenzyme than the kidney apoenzyme. When animals were fed a pyridoxinedeficient diet, the liver and kidney apodecarboxylase was markedly reduced, although that of the brain remained intact. The decreased decarboxylating capacity of tissues from pyridoxine-deficient animals was attributable to depletion of the coenzyme and also to loss of the protein moieties of the enzymes in liver and kidney. The degree of saturation of apoenzyme with coenzyme was greater with 5-hydroxytrypotophan than with 0-tyrosine as substrate in tissues from both normal and pyridoxine-depleted animals. Cortisone administration increased the inherent hepatic decarboxylating activity for both substrates in normal and deficient animals. However, when these activities were measured ...
Chemical compositions and classifica tion of five thermally altered carbonaceous chondrites

To establish the chemical group provenance of the five thermally altered carbonaceous chondrites Asuka (A-) 881551, Asuka-882113, Elephant Moraine (EET) 96026, Mulga (west), and Northwest Africa (NWA) 3133, we quantified 44 trace elements in each of them. We also analyzed Larkman Nunatak (LAR) 04318 (CK4), Miller Range (MIL) 090001 (CR2), Roberts Massif (RBT) 03522 (CK5) as reference samples as their chemical group affinity is already recognized. We conclude that Asuka-881551, Asuka-882113, and Mulga (west) are thermally metamorphosed CK chondrites. Compositionally, Elephant Moraine 96026 most resembles the CV chondrites. NWA 3133 is the most significantly thermally altered carbonaceous chondrite in our suite of samples. It is completely recrystallized (no chondrules or matrix remain), but its bulk composition is consistent with a CV–CK clan provenance. The thermally labile element (e.g., Se, Te, Zn, and Bi) depletion in NWA 3133 indicates a chemically open system during the heating episode. It remains unclear if the heat necessary for its thermal alteration of NWA 3133 was due to the decay of 26Al or was impact related. Finally, we infer that MIL 090001, Mulga (west), and NWA 3133 show occasional compositional signatures indicative of terrestrial alteration. The alteration is especially evident within the elements Sr, Ba, La, Ce, Th, U, and possibly Sb. Despite the alteration, we can still confidently place each of the altered chondrites within an established chemical group or clan.
Malignant teratoid medulloepithelioma: clinical-echographic-histopathologic correlation.

Abstract Introduction: Medulloepithelioma is a rare congenital intraocular neoplasm. The authors describe a case involving a 6-year-old girl who presented with leukocoria and an inflamed red eye. The important clinical and histopathologic features of this condition are reviewed in correlation with echographic findings. (J AAPOS 2001;5:395-7)
Late rupture of the flexor tendons as a complication of replacement arthroplasty

A case of attritional rupture of the flexor tendons secondary to metacarpophalangeal (MP) replacement arthroplasty for treatment of rheumatoid arthritis is reported. This complication is thought to be the result of resection of the palmar plate during the arthroplasty that was performed 5 1/4 years previously. Although not previously reported, it could be an expected late result if the palmar plate is excised during arthroplasty.
An embryonic nation

Liberal views on human-embryo technology make China ideal to become a world leader in this field. Xiangzhong Yang explores its potential.
Ribosomal Protein L9 is the Product of GRC5, a Homolog of the Putative Tumor Suppressor QM in S. cerevisiae

Genes encoding members of the highly conserved QM family have been identified in eukaryotic organisms from yeast to man. Results of previous studies have suggested roles for QM in control of cell growth and proliferation, perhaps as a tumor suppressor, and in energy metabolism. We identified recessive lethal alleles of the Saccharomyces cerevisiae QM homolog GRC5 that increased GCN4 expression when present in multiple copies. These alleles encode truncated forms of the yeast QM protein Grc5p. Using a functional epitope-tagged GRC5 allele, we localized Grc5p to a 60S fraction that contained the large ribosomal subunit. Two-dimensional gel analysis of highly purified yeast ribosomes indicated that Grc5p corresponds to 60S ribosomal protein L9. This identification is consistent with the predicted physical characteristics of eukaryotic QM proteins, the highly biased codon usage of GRC5, and the presence of putative Rap1p-binding sites in the 5' sequences of the yeast GRC5 gene.
HIV-1 infection: fooling the gatekeeper

Why are humans particularly susceptible to HIV-1, whereas our monkey cousins are impervious to the virus? Part of the answer may lie with the virus' interaction with a cellular system of defense ( pages 1138–1143 ).
Large-Scale Simulations of Fluctuating Biological Membranes

We present a new computational model for lipid bilayers that allows the simulation of membrane systems on the micrometer scale. In our model, each ∼25 nm2 patch of bilayer is represented by a spherical particle. Mimicking the forces of hydrophobic association, many-body interactions suppress the exposure of each sphere's equator to the implicit solvent. This driving force towards high equatorial density stabilizes two-dimensional aggregates without necessitating crystalline order. This allows us to match both the surface fluidity and bending elasticity of natural lipid membranes. We illustrate the usefulness of our model by computing the response of a bilayer to mechanical perturbations, such as deformations caused by an extending filopod.View Large Image | View Hi-Res Image | Download PowerPoint Slide
Xylitol enhances bacterial killing in the rabbit maxillary sinus.

Objectives: Factors that alter airway surface liquid (ASL) ionic concentrations may influence the course of sinusitis. Xylitol has been shown to effect ASL ionic composition in vitro and to reduce nasal bacterial carriage, otitis media, and dental caries in vivo. We examined the effect of xylitol on experimental sinusitis in the rabbit model. Study Design: Prospective randomized controlled study of xylitol, saline, and Pseudomonas aeruginosa administration to the rabbit maxillary sinus. Methods:P. aeruginosa was administered to the sinuses of 26 New Zealand white rabbits. Saline was placed in the left maxillary sinus and xylitol in the right. The rabbits were randomly assigned to one of three groups: one, simultaneous administration of bacteria and solutions with bacterial analysis at 20 minutes, 11 rabbits; two, preadministration of solutions 1 hour before bacterial infection with analysis at 20 minutes, 11 rabbits; three, established sinusitis, 4 rabbits had daily injections of solutions for 5 days starting 7 days after P. aeruginosa administration. Results: In group 1, 6.96% of injected bacteria were retrieved on the left (saline), whereas 0.095% were retrieved on the right (xylitol) (P = .034). In group 2, 5.64% of inoculum was recovered from the left and 2.89% from the right (P = .188). Group 3 demonstrated evidence of sinusitis with recovery of noninoculate bacteria. with no difference between right and left. Conclusions: Xylitol reduces experimental sinusitis when administered simultaneously with bacteria. Its effect in established sinusitis is less clear. A role may exist for xylitol in nasal irrigation fluid in human disease.
A note on the efficiency of the cochrane-orcutt estimator of the ar(1) regression model

Abstract This paper shows that the Cochrane-Orcutt transformation which deletes the initial observation of the AR(1) regression model with known autocorrelation is strictly less efficient than a weighted generalized least squares estimator which gives the initial observation less weight than the true model requires, and may be more or less efficient than an estimator which gives the initial observation more weight than required. It also shows that the estimator based on the Cochrane-Orcutt transformation is strictly less efficient than one based on the Prais-Winsten transformation, if the AR(1) process has a finite past. These results give further support to the conclusion that, whenever possible, the estimator based on Prais-Winsten transformation should be used.
Facile Route to Organoboron Quinolate Polymers through Boron-Induced Ether Cleavage

Two new organoboron quinolate polymers were prepared under exceptionally mild conditions via a novel polycondensation reaction involving boron-induced ether cleavage. The polymers, which contain both the boron and quinolato moieties in the main chain, were characterized by multinuclear and 2D NMR, gel permeation chromatography, and matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. They are readily soluble in common organic solvents and thermally stable to >300 °C according to thermogravimetric analysis. The photophysical properties strongly depend on the nature of the conjugated bridge connecting the organoboron quinolato groups. Therefore, with a highly delocalized Th−C6H4−Th (Th = thiophene) linker, the lowest energy absorption corresponds to intramolecular charge transfer (ICT) from this conjugated linker to the pyridyl moiety. In contrast, with a less delocalized biphenyl linker, ICT occurs from the fluorene moiety of the diboron monomer to the pyridyl rings on ...
Predictors of disability in migraineurs referred to a tertiary clinic: neck pain, headache characteristics, and coping behaviors.

Objective.— The aim of this retrospective study was to determine if neck pain, select headache characteristics, and migraine-related coping response predicted disability in migraineurs referred to a tertiary headache clinic. Methods.— Patients seeking treatment at a neurology-based headache clinicwere included if they met diagnostic criteria for migraine with or without aura according to the International Headache Society (1.1, 1.2). Subjects completed a self-report headache history form and a detailed headache and neurologic examination. The headache history form assessed: 1)weekly headache frequency; 2) number ofweekly severe headaches; 3) presence of migrainerelated neck pain; 4) photophobia; 5) phonophobia; 6) headache duration; 7) vomiting; 8) monthly headache-free days; and 9) behavioral coping style. Disability was assessed using a self-report inventory (HIT-6). Results.— Self-reported headache severity, frequency, and headache-free days were strongly associated with disability. The presence of neck pain during migraine and one's coping response to migraine significantly predicted disability independent of headache characteristics. Conclusions.— These data suggest the need for prospective research exploring the causal mechanisms by which neck pain and coping response influence disability and underscores the importance of multidisciplinary approaches to headache management.
No cometesimals in the inner solar system

Ultraviolet measurements made by Voyager 2, apparently showing a rapid decrease in hydrogen Lyman-alpha emission with distance from the sun, were taken by Donahue et al. (1987) as evidence for a source of atomic hydrogen in the very local interstellar medium (VLISM). The suggested source of the hydrogen is a class of small comets at solar distances of about 1 AU. This claim has been adduced as evidence for a theory that the earth is subject to a large influx of cometary material significantly affecting atmospheric evolution. The Voyager 2 data have been reanalyzed, and it is shown that no source of hydrogen in the VLISM is required other than the inflow of neutral atoms.
Selective modulation of promoter recruitment and transcriptional activity of PPARγ

Peroxisome proliferator-activated receptor gamma (PPARgamma) is a nuclear receptor regulated by the insulin-sensitizing thiazolidinediones (TZDs). We studied selective modulation of endogenous genes by PPARgamma ligands using microarray, RNA expression kinetics, and chromatin immunoprecipitation (ChIP) in 3T3-L1 adipocytes. We found over 300 genes that were significantly regulated the TZDs pioglitazone, rosiglitazone, and troglitazone. TZD-mediated expression profiles were unique but overlapping. Ninety-one genes were commonly regulated by all three ligands. TZD time course and dose-response studies revealed gene- and TZD-specific expression kinetics. PEPCK expression was induced rapidly but PDK4 expression was induced gradually. Troglitazone EC50 values for PEPCK, PDK4, and RGS2 regulation were greater than those for pioglitazone and rosiglitazone. TZDs differentially induced histone acetylation of and PPARgamma recruitment to target gene promoters. Selective modulation of PPARgamma by TZDs resulted in distinct expression profiles and transcription kinetics which may be due to differential promoter activation and chromatin remodeling of target genes.
Unraveling the Exciton Quenching Mechanism of Quantum Dots on Antimony-Doped SnO2 Films by Transient Absorption and Single Dot Fluorescence Spectroscopy

Integrating quantum dots (QDs) into modern optoelectronic devices requires an understanding of how a transparent conducting substrate affects the properties of QDs, especially their excited-state dynamics. Here, the exciton quenching dynamics of core/multishell (CdSe/CdS3MLZnCdS2MLZnS2ML) quantum dots deposited on glass, tin oxide (SnO2), and antimony (Sb)-doped tin oxide (ATO) films are studied by transient absorption and single QD fluorescence spectroscopic methods. By comparing ensemble-averaged fluorescence decay and transient absorption kinetics, we show that, for QDs on SnO2, the exciton is quenched by electron transfer from the QD to SnO2. At the QD–ATO interface, much faster exciton quenching rates are observed and attributed to fast Auger recombination in charged QDs formed by Fermi level equilibration between the QD and n-doped ATO. Single QDs on SnO2 and ATO show similar blinking dynamics with correlated fluctuations of emission intensities and lifetimes. Compared to QDs on SnO2, QDs on ATO fil...
An Ina Jo® proof manager for the formal development method

This paper describes methods for decomposing large conjectures into smaller ones in order to make their proof easier and for limiting the amount of reproving that occurs when a specification is modified. It proposes a tool, based on these methods, for managing the proofs of conjectures about an evolving specification.
Cognitive-behavioral treatment of bulimia nervosa: a controlled evaluation.

Abstract A verbal cognitive restructuring (CR) method was compared to CR plus exposure and vomit prevention (CR/EVP) in the treatment of patients with bulimia nervosa. CR/EVP was significantly more effective than CR in reducing binge eating and vomiting although the two treatments were equally credible and met with similar patient compliance. At 1-yr follow-up CR/EVP S s were completely abstinent. CR/EVP also resulted in significantly greater improvements on several measures of psychopathology. At 1-yr follow-up, CR/EVP S s showed major changes in eating habits and cognitions and feelings concerned with food. On these and general measures of psychopathology, CR/EVP S s scored in the nonproblem, nonpatient range. S s' prior lowest weights as adolescents were significantly related to treatment outcome.
The management of appendiceal mass in children: is interval appendectomy necessary?

In this study we aimed to show that performing interval appendectomy is unnecessary in the management of appendiceal mass in children. Between 1990 and 1996, 866 patients were treated for appendicitis. Abdominal ultrasonography (USG) was performed in patients who were admitted with abdominal pain, vomiting, and fever accompanying a mass in the right lower quadrant. Seventeen patients (12 boys and 5 girls, with a mean age of 9.5 years) with a mass in the appendiceal lodge and no abscess formation were treated conservatively. Appendectomy was performed on any patients with perforated or unperforated appendicitis who had an appendiceal abscess with a mass in the right iliac fossa. Three-agent antibiotic therapy was administered for at least 1 week. These patients were discharged after a mean hospital time of 9.7 days if regression of the mass was seen ultrasonographically. They were followed up for 1–60 months by physical examination and USG, and 11 of the 17 also underwent barium enema. USG demonstrated disappearance of the mass and barium enema showed a normal appendix in 10 of the 11 patients. No recurrent appendicitis was detected during follow-up for 1–7 years. This study shows that appendiceal masses that are perforated, but localized with no fluid content revealed by USG, can be treated conservatively even if they are detected late.
Fatalities from venomous and nonvenomous animals in the United States (1999-2007).

Objective To review recent (1999–2007) US mortality data from deaths caused by nonvenomous and venomous animals and compare recent data with historic data. Methods The CDC WONDER Database was queried to return all animal-related fatalities between 1999 and 2007. Rates for animal-related fatalities were calculated using the estimated 2003 US population. Inclusion criteria included all mortalities that were a consequence of bite, contact, attack, or envenomation (ICD-10 codes W53–W59 and X20–X29). Results There were 1802 animal-related fatalities with the majority coming from nonvenomous animals (60.4%). The largest percentage (36.4%) of animal-related fatalities was attributable to "other mammals," which is largely composed of farm animals. Deaths attributable to Hymenoptera (hornets, wasps, and bees) have increased during the past 60 years in the United States and now account for more than 79 fatalities per year and 28.2% of the total animal-related fatalities from 1999 to 2007. Dog-related fatalities have increased in the United States, accounting for approximately 28 fatalities per year and 13.9% of the total animal-related fatalities. Conclusions Prevention measures aimed at minimizing injury from animals should be directed at certain high-risk groups such as farmworkers, agricultural workers, and parents of children with dogs.