cssi/SciSciGPT-SciSciNet huggingface dataset:
Mycobacterium tuberculosis gene expression during environmental conditions associated with latency.

The physiological character of Mycobacterium tuberculosis (MTB) during latent disease has been difficult to investigate and remains largely unknown. The lack of accessible animal models which reproduce the full repertoire of latent disease features has made it challenging to apply conventional genetic techniques to identify key genes involved in survival of MTB during latent disease. Several studies in this issue of ‘Tuberculosis’ utilize an alternative approach which examines in vitro conditions that are thought to be part of the environment encountered by latent MTB. These studies employ expression profiling techniques to elucidate transcriptional regulatory networks that are part of MTB’s genetically programmed response. Expression networks engaged by MTB to survive in vitro conditions can provide a window into the inner workings of this notorious pathogen. In vitro models to investigate environmental conditions associated with latency
A control system approach to cardiovascular reactivity: behavioral models that behave

The control system mode of analysis of organism-environment interactions is described and used to derive an explanation of cardiovascular reactivity. This description reveals that a negative feedback control system continuously realizes a goal or purpose over time by producing output that negates the effects of unpredictable and uncontrollable disturbances on a physical variable corresponding to that purpose. Data from tracking experiments fit the control system analysis, but cannot be described by S-O-R analyses or by cognitive analyses that, unlike the control system analysis, do not correctly introduce physical time. Simple computer simulations of negative feedback control systems produce data that are almost perfectly correlated with each subject's behavior over time--these models behave. The existence of consistent behavioral results despite uncontrollable and unpredictable influences, the simple requirements for a negative feedback system, and the identification of continuously varying purposes as representing the unfolding of behavioral events over time argue for the testable hypothesis that most behavior is produced by negative feedback control. It is suggested that error in the operation of negative feedback control systems modulates cardiac performance. The ability of control systems to behave gives this explanation advantages over other theories of reactivity. A program for testing this explanation is described. Language: en
Volume and Coverage Estimation of Spray Deposition Using an Amino Nitrogen Colorimetric Reaction

A common laboratory color (ninhydrin) reaction to quantify the amount of amino acids in solution can be used to calibrate research microsprayers to deposit a desired quantity of active ingredient onto a surface. Calibration can be achieved without visible residue on equipment, operators, or targets. A modification of the technique can be used to measure canopy penetration.
Diagnostic approach to lymphoid lesions of major salivary glands

Among lesions of the major salivary glands (parotid, submandibular, and sublingual glands), those with a prominent lymphoid component are encountered frequently in the surgical pathology laboratory and range from reactive lesions to benign and malignant neoplasms. A majority of these lymphoid lesions have a co-mingled epithelial component, which also ranges from benign to malignant. As a result, many of these lesions have similar and overlapping histopathologic features, and attention to details, sometimes subtle, is required to accurately distinguish one from another. This review will discuss these lymphoid-epithelial lesions of major salivary glands, with emphasis on features that help in the differential diagnosis. Entities discussed include lymphoepithelial sialadenitis, HIV-associated salivary gland disease, extranodal marginal zone B-cell lymphoma, lymphoepithelial carcinoma, lymphadenoma, sebaceous lymphadenocarcinoma, chronic sclerosing sialadenitis, and Warthin tumour.
Research Note The Partisan Bias in Senate Elections

Recent Senate elections have seen a strong pro-Republican bias, resulting from inroads in the small population states overrepresented in the Senate and from lean victory margins. The bias allows th...
Rate Constants for Peroxidation of Polyunsaturated Fatty Acids and Sterols in Solution and in Liposomes

Rate constants for autoxidation propagation of several unsaturated lipids in benzene solution at 37 degrees C and in phosphatidylcholine liposomes were determined by a linoleate radical clock. This radical clock is based on competition between hydrogen atom abstraction by an intermediate peroxyl radical derived from linoleic acid that leads to a trans,cis-conjugated hydroxyoctadecadienoic product and beta-fragmentation of the same peroxyl that gives the trans,trans-product hydroxyoctadecadienoic acid. Rate constants determined by this approach in solution relative to linoleic acid (k(p) = 62 M(-1) s(-1)) were: arachidonic acid (k(p) = 197 +/- 13 M(-1) s(-1)), eicosapentaenoic acid (k(p) = 249 +/- 16 M(-1) s(-1)), docosahexaenoic acid (k(p) = 334 +/- 37 M(-1) s(-1)), cholesterol (k(p)= 11 +/- 2 M(-1) s(-1)), and 7-dehydrocholesterol (k(p)= 2260 +/- 40 M(-1) s(-1)). Free radical oxidations of multilamellar and unilamellar liposomes of various mixtures of glycerophosphatidylcholine molecular species were also carried out. In some experiments, cholesterol or 7-dehydrocholesterol was incorporated into the lipid mixture undergoing oxidation. A phosphatidylcholine bearing a linoleate ester at sn-2 was a component of each liposome peroxidation reaction and the ratio of trans,cis/trans,trans (t,c/t,t)-conjugated diene oxidation products formed from this phospholipid was determined for each oxidation reaction. This t,c/t,t-product ratio from linoleate was used to "clock" liposome constituents as hydrogen atom donors in the lipid bilayer. Application of this lipid bilayer radical clock gives relative autoxidation propagation rate constants of arachidonate (20:4), eicosapentaenoate (20:5), docosahexaenoate (22:6), and 7-dehydrocholesterol to be 115 +/- 7, 145 +/- 8, 172 +/- 13, and 832 +/- 86, respectively, a reactivity trend that parallels the one in solution. We also conclude from the liposome oxidations that linoleate peroxyl radicals at different positions on the eighteen-carbon chain (at C-9 and C-13) have different kinetic properties. This is in contrast to the results of solution oxidations of linoleate in which the C-9 and C-13 peroxyl radicals have similar reactivities. We suggest that peroxyl radical beta-scission depends on solvent polarity and the polarity of the local environment of peroxyl radicals in liposomal oxidations depends on the position of the peroxyl radical on the 18-carbon chain.
Peripheral blood mononuclear cells develop into multinucleated osteoclasts in tissue culture.

Background Previous studies have shown that osteoclasts are derived from mononuclear cells of hemopoietic bone marrow and peripheral blood. The purpose of this study was to demonstrate the presence of multinucleated osteoclasts after adding mononuclear cells from peripheral blood into established explants of fetal mouse calvaria in vitro. Methods In order to utilize osteoclast-free bone, the fetal calvariae were obtained from 13–14-day pregnant Swiss Webster mice and cultured in BGJb medium for 9 days. At day 9, peripheral blood mononuclear cells were isolated as a light density layer from adult Swiss Webster mice with the Ficoll-Paque density gradient separation method and co-cultured with the osteoclast-free, fetal mouse calvaria. Results After 10 days of co-culture, multinucleated cells, which have all the characteristics of osteoclasts, were found in juxtaposition to seams of woven bone. Two multinucleated osteoclasts per one million light density peripheral blood mononuclear cells were found in the experimental group; none were found in the mononuclear cell-free control group. Conclusions Peripheral blood mononuclear cells can give rise to multinucleated osteoclasts in developing bone in vitro but will not develop without bone. © 1996 Wiley-Liss, Inc.
Substrate Binding Is the Rate-limiting Step in Thromboxane Synthase Catalysis

Abstract Thromboxane synthase (TXAS) is a “non-classical” cytochrome P450. Without any need for an external electron donor, or for a reductase or molecular oxygen, it uses prostaglandin H2 (PGH2) to catalyze either an isomerization reaction to form thromboxane A2(TXA2) or a fragmentation reaction to form 12-l-hydroxy-5,8,10-heptadecatrienoic acid and malondialdehyde (MDA) at a ratio of 1:1:1 (TXA2:heptadecatrienoic acid:MDA). We report here kinetics of TXAS with heme ligands in binding study and with PGH2 in enzymatic study. We determined that 1) binding of U44069, an oxygen-based ligand, is a two-step process; U44069 first binds TXAS, then ligates the heme-iron with a maximal rate constant of 105–130 s−1; 2) binding of cyanide, a carbon-based ligand, is a one-step process with k on of 2.4m −1 s−1 andk off of 0.112 s−1; and 3) both imidazole and clotrimazole (nitrogen-based ligands) bind TXAS in a two-step process; an initial binding to the heme-iron with on-rate constants of 8.4 × 104 m −1s−1 and 1.5 × 105 m −1 s−1 for imidazole and clotrimazole, respectively, followed by a slow conformational change with off-rate constants of 8.8 s−1 and 0.53 s−1, respectively. The results of our binding study indicate that the TXAS active site is hydrophobic and spacious. In addition, steady-state kinetic study revealed that TXAS consumed PGH2 at a rate of 3,800 min−1 and that thek cat/K m for PGH2 consumption was 3 × 106 m −1 s−1. Based on these data, TXAS appears to be a very efficient catalyst. Surprisingly, rapid-scan stopped-flow experiments revealed marginal absorbance changes upon mixing TXAS with PGH2, indicating minimal accumulation of any heme-derived intermediates. Freeze-quench EPR measurements for the same reaction showed minimal change of heme redox state. Further kinetic analysis using a combination of rapid-mixing chemical quench and computer simulation showed that the kinetic parameters of TXAS-catalyzed reaction are: PGH2 bound TXAS at a rate of 1.2–2.0 × 107 m −1s−1; the rate of catalytic conversion of PGH2to TXA2 or MDA was at least 15,000 s−1 and the lower limit of the rates for products release was 4,000–6,000 s−1. Given that the cellular PGH2concentration is quite low, we concluded that under physiological conditions, the substrate-binding step is the rate-limiting step of the TXAS-catalyzed reaction, in sharp contrast with “classical” P450 enzymes.
Multiple Isoforms of Arabidopsis Casein Kinase I Combine Conserved Catalytic Domains with Variable Carboxyl-Terminal Extensions

Three cDNA clones encoding isoforms of casein kinase I (CKI) were isolated from Arabidopsis thaliana. One full-length clone, designated CKI1, contained an open reading frame of 1371 bp encoding a protein of 51,949 D with an isoelectric point of 9.7. In addition to the highly conserved catalytic domain (of about 300 amino acids), the Arabidopsis CKI isoforms contain 150 to 180 amino acid carboxyl-terminal extensions, which show among themselves a lower level of sequence conservation. These extensions do not show any sequence similarity to nonplant CKI isoforms, such as rat testis CKI[delta], which is their closest isolated homolog, or to yeast CKI isoforms. Three additional isoforms of Arabidopsis CKI were found in the data bases of expressed sequence tags and/or were isolated serendipitously in nonspecific screening procedures by others. One of them also shows a carboxyl-terminal extension, but of only 80 amino acids. Casein kinase activity was detected in the soluble fraction of Escherichia coli strains expressing the CKI1 protein. This activity showed the crucial properties of CKI, including the ability to phosphorylate the D4 peptide, a specific substrate of CKI, and inhibition by N-(2-aminoethyl)-5-chloroisoquinoline-8-sulfonamide, a specific CKI inhibitor. Like several recombinant CKI isoforms from yeast, CKI1 was able to phosphorylate tyrosine-containing acidic polymers.
A comparison of two weight management programs for adults with mobility impairments.

Background: Individuals with physical disabilities experience disparities in obesity; yet few interventions have incorporated accommodations necessary for weight loss in this population. Objective/Hypothesis: This project compared the effectiveness of two weight loss interventions among individuals with physical disabilities. Methods: Adults with physical disabilities who were overweight or obese were randomized across two diet approaches: a modified version of the MyPlate diet (usual care (UC)) and a modified Stoplight Diet (SLDm) supplemented with portion-controlled meals. Project staff met monthly with each participant to measure weight, 24-recalls of diet intake, self-tracking of foods and beverages, and physical activity during the preceding month. Results: Of 126 enrollees, 70% completed the initial 6-month diet phase and 60% of these completed a 6-month follow-up phase. Participants in the SLDm group reduced weight and BMI during the 6 month intervention, and maintained or lost more weight during the 6 month maintenance period. Alternately, the UC diet resulted in a reduction in weight and BMI only at 6 months. BMI from baseline was significantly more improved for SLDm than UC and, among those who lost weight, the SLDm group lost more weight at 6 and 12 months. Conclusions: These results demonstrate that interventions with proper design and accommodations can overcome the barriers to weight loss unique to individuals with mobility impairments with low income. Additionally, the results suggest that using portion control may be more effective than teaching portion sizes. Published by Elsevier Inc.
A characterization theorem for the Fourier transform on Rn

Abstract In this paper we develop a characterization of the Fourier transform as a continuous operator from L 2 (R n ) to L 2 (R n ) behaving like the Fourier transform under rotations, dilation, and translations. This gives a new approach to a result of A. Hertle [6] based on the Hecke-Bochner identities.
Search for a model polymer blend

The thermodynamics of binary and multicomponent mixtures comprising polymethyl-butylene, polyethylbutylene, and polymethylbutylene-block-polyethylbutylene was studied by small-angle neutron scattering. The Flory-Higgins interactions parameter, deduced from these measurements, was independent of blend composition, as well as molecular weight and molecular architecture of the components, over the accessible temperature (27-201°C) and pressure (0.01-0.86 kbar) range. At temperatures above 130°C, the interaction parameter becomes independent of pressure. These findings are compared with previous experimental studies on the thermodynamics of polymer blends. To our knowledge, this level of agreement with the Flory-Huggins theory has not been seen in any other polymer blend.
Effects of interleukin-1β on the steroid-induced luteinizing hormone surge: Role of norepinephrine in the medial preoptic area

Interleukin-1beta (IL-1beta), a cytokine, is known to inhibit the preovulatory surge of luteinizing hormone (LH); however, the mechanism by which it does so is unclear. This study was done to see if this effect is mediated through hypothalamic catecholamines. Adult female Sprague-Dawley rats were ovariectomized and implanted with a push-pull cannula in the medial preoptic area (MPA) of the hypothalamus. They were injected subcutaneously with 30 microg of Estradiol on the day 8 after surgery and with 2mg of Progesterone on day 10 at 1000 h. On the day of perfusion (day 10), the rats were injected with IL-1beta or its vehicle at 1300 h. Perfusate samples from the MPA and blood samples from a jugular catheter were collected from 1300 to 1800 h. Catecholamine concentrations in the perfusate were measured using high performance liquid chromatography (HPLC)-EC and LH levels in the serum using RIA. Norepinephrine release in the MPA of control rats increased significantly at 1530, 1600, and 1630 h paralelling an increase in LH at 1600 h. In contrast, IL-1beta treatment blocked the LH surge and the rise in norepinephrine release in the MPA. No changes were observed in dopamine release, both in control and IL-treated animals. These results demonstrate for the first time that IL-induced suppression of the LH surge is probably mediated through inhibition of norepinephrine release in the MPA.
The Accurate Solution of Poisson's Equation by Expansion in Chebyshev Polynomials

A Chebyshev expansion technique is applied to Poisson's equation on a square with homogeneous Dirichlet boundary conditions. The spectral equations are solved in two ways - by alternating direction and by matrix diagonalization methods. Solutions are sought to both oscillatory and mildly singular problems. The accuracy and efficiency of the Chebyshev approach compare favorably with those of standard second- and fourth-order finite-difference methods.
Creep behavior of nonburning Ti-35V-15Cr-xC alloys

A comparison is made between the creep behavior of the Ti-35V-15Cr and Ti-35V-15Cr-0.2C alloys at 500 to 580 °C within the stress range of 200 to 300 MPa. The creep resistance of Ti-35V-15Cr-0.2C is considerably improved by the incorporation of Ti2C particulates into the Ti-35V-15Cr-0.2C matrix.
Government borrowing and the long-term interest rate: Application of an extended loanable funds model to the Slovak Republic

Extending the open-economy loanable funds model, this paper finds that more government borrowing as a percent of GDP leads to a higher government bond yield, that a higher real money market rate, a higher expected inflation rate, a higher EU government bond yield, or a decrease in the Slovak nominal effective exchange rate would increase the Slovak government bond yield, and that the positive coefficient of the percent change in real GDP is insignificant at the 10% level. When the standard closed- economy or open-economy loanable funds model is considered, except that the positive coefficient of the ratio of the net capital inflow to GDP is insignificant at the 10% level, other results are similar.
Towards the Simple Economics of Natural Liberty: An Exploratory Analysis

Individuals with legally protected endowments have incentives to allow maximal liberties of purchase or sale to persons on the opposing sides of potential trades. Unless overtly restricted, potential buyers and sellers will be allowed freedom of entry into all markets, thereby insuring maximization of combined consumer and producer surplus or rent. Since liberty, as defined, is a valued but not a scarce good, it is optimally utilized when it is not valued at the margin. The relationship between liberty and rent is examined, and individuals have incentives to extend liberties to others as means of protecting their own rents. Copyright 1987 by WWZ and Helbing & Lichtenhahn Verlag AG
Volumetric reduction in left subgenual prefrontal cortex in early onset depression.

Abstract Background: Subgenual prefrontal cortex (SGPFC) volume reduction has been reported in middle age adults with major depression (MD) or bipolar affective disorder. In this study, the authors test the hypothesis that SGPFC reduction is present in adolescent onset MD, and examine differences in the magnitude of reduction in younger versus older women. Methods: Subgenual prefrontal cortex volume was measured from T1 weighted MR images in (1) 30 young women with early onset MD versus eight age-matched controls, and (2) 18 middle aged women with recurrent MD versus nine age- matched controls. Results: Left SGPFC volume was reduced in adolescent and middle aged females with depression. The magnitude of the difference between depressed and control groups (average 19% difference) was similar in younger and older women. Conclusions: Left subgenual cingulate volume reductions are present in young women with adolescent onset MD.
Wiener index extension by counting even/odd graph distances.

Chemical structures of organic compounds are characterized numerically by a variety of structural descriptors, one of the earliest and most widely used being the Wiener index W, derived from the interatomic distances in a molecular graph. Extensive use of such structural descriptors or topological indices has been made in drug design, screening of chemical databases, and similarity and diversity assessment. A new set of topological indices is introduced representing a partitioning of the Wiener index based on counts of even and odd molecular graph distances. These new indices are further generalized by weighting exponents which can be optimized during the quantitative structure−activity/−property relationship (QSAR/QSPR) modeling process. These novel topological indices are tested in QSPR models for the boiling temperature, molar heat capacity, standard Gibbs energy of formation, vaporization enthalpy, refractive index, and density of alkanes. In many cases, the even/odd distance indices proposed here giv...
Parametric studies for tiltrotor aeroelastic stability in high-speed flight

The influence of several system design parameters on tiltrotor aeroelastic stability is examined for the high-speed (axial) flight mode. Coupling of the rotor flapping modes with the wing elastic modes produces a whirl motion, typical of tiltrotors, that can become unstable at high speeds. The sensitivity of this instability with respect to rotor frequencies, wing stiffness, forward wing sweep, and rotor thrust level is examined. Some important new trends are identified regarding the role of blade lag dynamics and forward wing sweep in tiltrotor aeroelastic stability. The blade lag frequency may be tuned to improve tiltrotor stability, and forward wing sweep is destabilizing because of changes in rotor force components associated with the sweep.
On the spectrum of some singular equations in magnetohydrodynamics.

A class of singular differential equations that often occurs in problems in magnetohydrodynamics, plasma physics, and astrophysics is studied; first by means of the specific and fairly straightforward example of motions in a stratified magnetofluid, and secondly in terms of the nature of the eigenvalue spectrum for the more general class of problems. It is shown that in the absence of discontinuities in the basic profiles, the eigenvalue spectrum is real and continuous, and no discrete spectrum exists. Bounds are obtained on the location of the continuous spectrum.
Part II: The photic environment of clear tropical seas during the day.

Abstract The visible Spectrum of sunlight was measured in quantal units. In air, the irradiance spectrum is broad and flat under both clear and overcast conditions. Measured near the surface, the irradiance spectrum of upwelling light is narrower and more blue than that of downwelling light. The angular distribution of underwater light was determined by restricting the collection angle of the light receptor. The total intensity and the spectrum of these radiance measurements are interrelated. The radiance spectrum of downwelling light is broad, while that of horizontal light is less intense, narrower and shifted to the blue. The radiance spectrum of upwelling light depends on total depth and the proximity of a reflective substrate. Measured far from the bottom, it is narrow and blue, but broadens as the receptor approaches the substrate.
Anatomy and Dimensions of the Gluteus Medius Tendon Insertion

Purpose: The purpose of this study was to determine the area, dimensions, and orientation of the gluteus medius footprint to provide an improved understanding of its insertional anatomy. Methods: Eight fresh-frozen cadaveric hips were dissected, leaving only the most distal gluteus medius tendon attached to the greater trochanter. The tendon insertion footprint and proximal femur were digitized and mapped by use of 3-dimensional computer navigation software. The area, location, and dimensions of the tendon insertion were determined. Results: The gluteus medius tendon has 2 distinct insertion sites on the greater trochanter, the lateral facet and the superoposterior facet. The mean areas of insertion onto the lateral and superoposterior facets were 438.0 mm 2 (SD, 57.7 mm 2 ) and 196.5 mm 2 (SD, 48.4 mm 2 ), respectively. The lateral facet footprint had a mean longitudinal dimension of 34.8 mm (SD, 4.3 mm), was angled at a mean of 36.8° (SD, 6.7°) relative to the long axis of the femur, and had a mean minimum width of 11.2 mm (SD, 1.8 mm). The superoposterior facet's shape approximated that of a circle, with a mean diameter of 17 mm (SD, 2.0 mm). Conclusions: The gluteus medius tendon has 2 distinct and consistent insertion sites onto the greater trochanter. This information will provide surgeons with a better understanding of the footprint anatomy when evaluating gluteus medius tendon tears. Clinical Relevance: Gluteus medius tendon tears can be a source of significant pain and morbidity. This study describes the anatomic morphology of this tendon insertion, which should aid in its repair when necessary.
Complex, Established “Legacy” Sectors: The Technology Revolutions That Do Not Happen

given rise to a steady stream of innovations in information and communications technology, along with medicine, agriculture, military, aerospace, and many other fields. For a quarter century, innovation policy in the United States has focused on the problems encountered by innovations in these and many other areas—especially on “the valley of death,” the gap in implementing innovation that occurs as technologies bring new functions to create new markets and innovators move from research to late-stage development. In contrast, almost no research has focused on a different but critical problem in innovation: fitting new technologies into established economic sectors where innovation is needed and potentially transformational, and where the record of success is much more meager. This is the problem we confront in this article. Put another way, how do we fit discontinuous technologies into established sectoral paradigms? Complex established “legacy” sectors—like energy, health delivery, the electric grid, building, and transport—present acute needs for systemwide technological innovation. Typically, the United States launches new technologies, and the new functionality they offer, into new territory, creating new economic activities. There was nothing quite like computing, telecommunications, aviation, electricity, or railroads before their advent. It is harder to launch innovations into established sectors occupied by incumbent firms and their aging technologies because they
The multifunctional estrogen receptor-alpha F domain

The members of the nuclear receptor superfamily act as transcriptional regulatory factors and exhibit a multidomain structure characterized as domains A-E/F. This review focuses on a small, relatively understudied region at the extreme carboxy-terminus of the estrogen receptor (ER) alpha, the F domain. The F domain contributes to differences in the activity of ER alpha and beta subtypes; it is required for tamoxifen’s agonist activity on an estrogen response element, and it modifies the receptor’s interactions with coregulators including steroid receptor coactivator-1. The differences between the F domains of the ER alpha and beta subtypes and among the other members of the nuclear hormone receptor superfamily may offer opportunities for selective control of the activity of these proteins.
Improved Probes for Hybrid Voltage Sensor Imaging

Hybrid voltage sensors (hVoS) probe membrane potential by coupling the fluorescence of membrane-anchored proteins to the movement of a membrane-embedded hydrophobic anion dipicrylamine. Fluorescence resonance energy transfer between these two components transduces voltage changes into fluorescence changes, providing a signal for imaging electrical activity in genetically targeted cells. To improve hVoS signals, we systematically varied the optical properties, membrane targeting motifs, and linkages of fluorescent proteins to optimize the normalized fluorescence change (ΔF/F) and signal/noise ratio. The best results were obtained with cerulean fluorescent protein tagged N-terminally with a GAP43 motif and C-terminally with a truncated h-ras motif. With 100 mV steps in PC12 cells, this probe produced ΔF/F = 26% (4 μM dipicrylamine), which was threefold greater than that obtained with the original farnesylated EGFP construct. We also obtained a fivefold greater signal/noise ratio, which was 70% of a theoretical optimum. We designate this GAP43-CerFP-t-h-ras construct as hVoS 2.0. With the aid of a theoretical analysis, we estimated that hVoS 2.0 places its fluorophore ∼40 A from the bilayer midplane. hVoS 2.0 performed well in cultured hippocampal neurons, where single action potentials produced clear fluorescence changes in a single trial. This improved probe should help investigators image voltage in genetically targeted neurons.
Free and total insulin integrated concentrations in insulin dependent diabetes.

Abstract Studies of the 24 hr insulin concentration profiles in diabetic subjects on chronic exogenous insulin have been hampered by the presence of endogenous anti-insulin antibody, which gives spurious estimates of radioimmunoassayable insulin concentrations. The introduction of polyethylene glycol precipitation of endogenous antibody has allowed development of reliable assays for determiniation of free and total insulin concentration in subjects on insulin therapy. This article reports our observations of plasma free and total insulin concentration in 50 Type I and Type II ambulatory insulin dependent diabetics, utilizing a continuous 24 hr blood withdrawal technique. In response to exogenous insulin, study subjects had marked elevations in insulin concentrations compared to controls. Mean free insulin integrated concentration was 3.5-fold higher in diabetics than nondiabetics. Mean total insulin integrated concentration was 868 μU/ml, more than 20 times in excess of total insulin concentration in nondiabetics. There was a wide range among diabetics in the percentage of total insulin in the free insulin fraction. Neither free nor total insulin integrated concentration correlated with dose of exogenous insulin. Free and total insulin concentration profiles showed a limited range of variation in insulin concentration during the 24 hr of study, no subject having a profile that mimicked that observed in nondiabetic subjects. Glucose integrated concentration showed no correlation with free insulin integrated concentration, however, it did correlate inversely with the percentage of total insulin in the free insulin fraction. These data emphasize the difficulty in establishing normal patterns of insulin among diabetic subjects on conventional subcutaneous insulin therapy.
CIM, data and standardization within the NBS AMRF

Abstract Computer-Integrated Manufacturing ( CIM ) is key to the factory of the future, shared data is key to integration, and interface standards are key to data-sharing. Within its Automated Manufacturing Research Facility ( AMRF ), the U.S. National Bureau of Standards is addressing issues of standardized interfaces in the four principal data activities of the automated factory: data preparation, data administration, data communication, and data-driven control. By means of such interface standards, the flexibly automated, robotics-based, computer-integrated factory of the future can be realized in a modular, easily integratable, multi-vendor form.
Developmental Programming: Insulin Sensitizer Treatment Improves Reproductive Function in Prenatal Testosterone-Treated Female Sheep

Prenatal testosterone (T) excess causes reproductive and metabolic disruptions including insulin resistance, attributes of women with polycystic ovary syndrome. This study tested the hypothesis that insulin resistance contributes toward severity of reproductive disruptions in prenatally T-treated females. Pregnant sheep were injected im with 100 mg of T-propionate semiweekly from d 30–90 of gestation. Immediately after the first breeding season, a subset of controls and prenatal T-treated (TR) sheep were administered an insulin sensitizer (rosiglitazone; 8 mg/d) orally for 8 months. Untreated control and prenatal T-treated females (T group) were studied in parallel. Biochemical analyses revealed rosiglitazone to be safe for use in sheep. Glucose tolerance tests performed before and after the insulin sensitizer treatment found that insulin sensitizer decreased cumulative insulin, cumulative insulin/glucose ratio, and insulin area under the curve by about 50% and increased the insulin sensitivity index by a...
“Orphan” phenotypes in gerontological research

It is argued that, in addition to investigations of life span parameters, a large number of biomedically important phenotypes can be profitably studied from a gerontological perspective. These would include “private” patterns of aging, especially in our own species, which exhibits extraordinary genetic heterogeneity. These, as well as a number of relatively common age-associated phenotypes, have been comparatively neglected by the gerontological community, and therefore warrant the designation as “orphan” phenotypes. From a tabulation of examples from each of the major body systems, five are elaborated upon: “hyperhippocampals,” defined as individuals with intrinsically enhanced functional reserve in relevant neural circuitry; patients with a heterogeneous set of pathologies collectively referred to as “normal pressure hydrocephalus”; patients with late life activation of herpes zoster; individuals with unusually early onset of loss of olfactory function; and geriatric subjects with unusual sensitivity to “jet lag.” (Aging Clin. Exp. Res. 5: 325–332, 1993)
A method of calibrating magnetometers on a spinning spacecraft

This paper describes a procedure for quantifying and compensating for angular offsets and slow-varying drifts associated with a flux-gate magnetometer onboard a spinning spacecraft. Such magnetometers have been down on numerous spacecraft such as IMP-8, DE-1, and ISTP/GEOTAIL, and similar instruments are currently proposed to fly on the ISTP/WIND spacecraft. Consequently, slight geometric misalignment of the sensor from their chosen axes will create errors in the measured signal. These misalignments can be quantified using perturbation theory and compensated in the data analysis process. The technique is applicable to magnetometers on spinning spacecraft. Also, over long time periods, the magnetometer will develop slight drifts in the electronic components, and these too can be quantified in the data analysis process. A technique is discussed that quantifies and compensates for such perturbations from the measurements. The technique has been successfully applied for the last sixteen years to IMP-8 magnetometer data and more currently to the GEOTAIL magnetometer data, and can be applied in a general way to measurements from any magnetometer onboard a spinning spacecraft. Further improvements in the technique are also discussed. >
Use of piperacillin, a semisynthetic penicillin, in the therapy of acute exacerbations of pulmonary disease in patients with cystic fibrosis

OUR ENTHUSIASM for this manuscript and the study which it reflects is in large measure related to the important question raised by Dr. Beaudry and his colleagues. Two reviewers developed significantly different degrees of enthusiasm for the study, although each had virtually the same underlying reservations. In a critique of the study, one of the reviewers wrote as follows: "Conclusions should be based on studies which meet the following criteria: (1) They should be well controlled and double blind; (2) they should compare the effects of drugs on three separate groups of patients who appear to be infected predominantly with (a) Pseudomonas.aeruginosa, (b) Pseudomonas aeruginosa and Staphylococcus attreus, and (c) Staphylococcus attreus, (3) the choice of patients should be restricted to those with mild or moderate disease with acute exacerbations in whom the effects of antibiotic regimens are most likely to be easily and reliably assessed; and (4) a large number of patients should be studied so that reliable statistical inferences can be drawn." Meanwhile, the other reviewer indicated the following: "The manuscript does not answer all the questions that could or should be resolved; however, it does give us a start. It is high time to address ourselves to the wisdom of a therapeutic approach that has never been adequately documented. The presence of pseudomonas or staphylococci, or both, in sputum cultures has never excited me very much. These patients have the same organisms when they are sick or not so sick (they are never well!). Treatment of these patients has been more of a ritual rather than a scientific approach." Authors, reviewers, and editors will all agree that the paper is not one which will allow the practicing physician to know precisely what to do. In our view, recommendations in reference to therapy (particularly antimicrobial therapy) too often are advanced ex cathedra. A wellconceived and well-executed study, done prospectively along the lines advocated by all and possibly (ideally?) involving several centers, would be most likely to provide clear answers. The parallel between the kind of study proposed and those which are initiated in an effort to advance therapy for children with leukemia is striking. Conversely, and sadly, the present state of affairs relative to the treatment of cystic fibrosis is often, a matter of opinion rather than fact. We hope that this manuscript will serve as a stimulus to the kind of study which is advocated by all concerned. R.E.M.
Condensed Tannin Concentration of Rhizomatous and Nonrhizomatous Birdsfoot Trefoil in Grazed Mixtures and Monocultures

Condensed tannins in forage legumes can be beneficial or detrimental to ruminant livestock performance, depending on concentration. The objective of this research was to determine condensed tannin concentration in birdsfoot trefoil (Lotus comiculatus L.) without rhizomes (BFT) and with rhizomes (RBFT) from grazed monocultures and mixtures. An additional objective was to investigate possible fluctuation of condensed tannin concentrations through the spring grazing season. In 1997, 'Norcen' BET and 'ARS-2620' RBFT were sown into pastures located at Columbia, MO; pastures were pure stands or mixtures with tall fescue (TF; Festuca arundinacea Schreb). Pastures were grazed in 1998 and 1999, and the BFT and RBFI components were hand clipped every 14 d throughout the spring of 1998 and 1999. Samples were analyzed for condensed tannin concen. tration by near infrared (NIR) reflectance spectroscopy with calibrations based on the vanillin-HCl colorimetric method. Condensed tannin concentrations of grazed BFT were lower in this study than concentrations reported in other studies. Averaged over both years BFT contained 11.4 g catechin equivalents (CE) kg -1 DM, and RBFI contained (P < 0.05) three times that amount (38.6 g CE kg -1 DM) Also, condensed tannin concentrations of the BFT component were 100% higher when BFT was grown in a mixture instead of a pure stand (P < 0.10); in 1999, they were 55% higher (P < 0.05). Finally condensed tannin concentration fluctuated over the spring of 1998 (P < 0.05), but not the spring of 1999. We concluded that condenses tannins in BFT are much lower than in RBFT, that condensed tannins in BFT decrease when grown with a tall fescue companion grass, and that concentrations can fluctuate in the spring as they do in the autumn.
Intracellular magnesium and insulin resistance : results in Pima Indians and Caucasians

Intracellular magnesium is a cofactor for numerous enzymes involved in carbohydrate metabolism. Magnesium accumulation is dependent upon insulin action and correlates with insulin-mediated glucose uptake. As Pima Indians are known to be insulin resistant, we investigated whether, in response to insulin infusion, they have lower erythrocyte magnesium accumulation than Caucasians. Insulin-mediated glucose uptake was determined by a euglycemic hyperinsulinemic glucose clamp in 29 obese nondiabetic volunteers: 15 Caucasians (8 males and 7 females) and 14 Pima Indians (8 males and 6 females). Pima Indians were younger than Caucasians (mean +/- SD, 28 +/- 7 vs. 39 +/- 8 yr; P < 0.01), but had similar body mass index and fasting/2-h plasma glucose concentrations. Despite higher steady state plasma insulin levels (692 +/- 260 vs. 540 +/- 70 pmol/L; P < 0.03), Pima Indians had lower insulin-mediated glucose uptake than Caucasians (108 +/- 20 vs. 244 +/- 32 mg/m2.min; P < 0.0001). The mean fasting plasma magnesium concentration was lower in Pima Indians than in Caucasians (0.79 +/- 0.05 vs. 0.85 +/- 0.06 mmol/L; P < 0.01), whereas the mean fasting erythrocyte magnesium concentrations (1.98 +/- 0.10 vs. 2.03 +/- 0.14 mmol/L) were similar in the 2 groups. In response to insulin infusion, erythrocyte magnesium content increased less in Pima Indians than in Caucasians (0.15 +/- 0.07 vs. 0.28 +/- 0.21 mmol/L; P < 0.03). However, this increase was similar in the 2 groups when values were adjusted for insulin-mediated glucose uptake. In conclusion, nondiabetic Pima Indians have a lower erythrocyte magnesium accumulation in response to insulin infusion; this is probably due to their high degree of insulin resistance. The biochemical and physiological consequences of decreased intracellular magnesium uptake are discussed.
Beyond the End of Nature: SRM and Two Tales of Artificity for the Anthropocene

In 1989, Bill McKibben wrote a now famous book declaring that anthropogenic climate change marked the ‘end of nature.’ Like threatened species, McKibben claimed, ideas can go extinct. The idea of n...
Persistence of the Ivantsov continuum despite the existence of a length scale.

We show that the continuous family of steadily advancing, shape-preserving solutions of the Ivantsov problem for dendritic crystal growth is not necessarily broken down to a discrete set by the introduction into the model of an effect which defines a natural length scale for the problem. Specifically, we give an exact solution of a model which includes a special anisotropic heat-loss term in the liquid phase, which can be used to define length and velocity scales for the problem. The resulting needle-crystal solutions for a given undercooling of the liquid form a continuous family. There is a definite relation between tip curvature and growth velocity for these solutions, but the latter is allowed to take any value above a finite lower limit.
Long-term persistence of two-year college students

This paper employs a theoretical model to explain the long-term persistence of students who began their postsecondary education in two-year institutions. The model was estimated on a national sample of 825 students who initially enrolled in 85 two-year institutions in the fall of 1971, and who were followed over a nine-year period. Although there were differences in the factors associated with persistence for men and women, the results tend to confirm the importance of person-environment fit as a salient influence on degree persistence and completion in postsecondary education. Measures of academic and social integration had the most consistent pattern of positive direct effects, and much of the influence of student precollege traits was indirect.
Soil Organic Carbon Stocks in a Large Eutrophic Floodplain Forest of the Southeastern Atlantic Coastal Plain, USA

Anthropogenic land use has significantly altered sediment and nutrient dynamics at watershed-scales, resulting in significant redeposition within large floodplain ecosystems. Some upland land uses have had documented negative effects on soil carbon (C) stocks, although the specific impacts of these disturbances on soil organic carbon (SOC) dynamics in depositional environments are poorly understood. Assessment of SOC stocks in floodplain environments will allow for more precise estimates of C distribution at watershed and regional scales. In this study, we measured SOC pools to depths of 100 and 200 cm in four distinct floodplain landscapes (natural levee, flats, mineral wetlands, organic wetlands) in a large bottomland forest within Congaree National Park, South Carolina, USA. Mean SOC stocks to a depth of 100 cm were 108–109 Mg C ha−1 in flats and levees, 193 Mg C ha−1 in mineral wetlands, and 533 Mg C ha−1 in organic wetlands. In addition, hydric soils contained significantly more SOC in deep horizons (100–200 cm depths). At a regional scale, similar alluvial soils within large floodplains were estimated to store approximately 0.l Pg of SOC. These results highlight the importance of inclusion of deep SOC storage in alluvial settings when estimating watershed C budgets.
Sexual conflict in humans: evolutionary consequences of asymmetric parental investment and paternity uncertainty

We argue that sexual conflict was a recurrent feature of human evolutionary history, just as it has been in every sexually reproducing species that does not practice life-long genetic monogamy. We suggest that the source of much of the conflict between men and women can be reduced to an asymmetry in reproductive biology. This asymmetry—fertilization and gestation occurring within women—produces (a) sex differences in minimum obligatory parental investment and (b) paternity uncertainty. We argue that these consequences of internal fertilization and gestation are responsible for many phenomena in humans, such as sexual coercion, commitment skepticism, sexual overperception, and a host of adaptations associated with sperm competition.
The Timeliness of Accounting Earnings as an Antecedent of Disclosure Informativeness of US Multinational Firms

The objective of this paper is to investigate how disclosure informativeness of U.S. multinational corporations varies with the informativeness of numbers produced by their financial accounting systems. We predict that firms whose current accounting numbers do not capture well the effects of the firm's current activities and outcomes on shareholder value proxied by earnings timeliness will institute better disclosure systems and improve their disclosure informativeness to compensate for their less informative accounting numbers. Disclosure informativeness is measured by analyst ratings of corporate disclosures provided in the annual volumes of the Report of The Financial Analysts Federation Corporate Information Committee. The informativeness of accounting numbers is proxied by the timeliness of earnings. We investigate whether the analysts' ratings vary with the timeliness of earnings by examining the cross‐sectional relation between properties of earnings timeliness and subsequent analyst ratings of corporate disclosure of 100 firms included in FORBES' survey of the largest U.S. multinationals. The results support a significant negative relation between the timeliness metrics and subsequent values of disclosure informativeness after controlling for other firm characteristics.
A reliable synthesis of 1,1-dimethylpyrazolium 5-oxides

Reliable syntheses of compounds having the novel 1,1-dimethylpyrazolium 5-oxide ring system are reported. The method involves treating the dimethylhydrazone of a β-ketoester with a small amount of concentrated sulfuric acid or other catalyst and heating under reduced pressure for 1–24 hours. In this manner two new members of the series have been prepared and characterized.
Time-dependent first-flight leakage rates for the general case of a two-region spherical medium

Abstract Closed form analytical expressions for the time-dependent first-flight leakage rates for the general case of a two-region spherical medium have been obtained using elementary functions. Two cases were considered both for a δ-distribution in time and isotropic source emission. The first case has a spatially uniform distributed source in the outer shell region. This result complements previous time-dependent solutions obtained for a sphere containing a central black region and a sphere containing a central void region. The second case has a spatially uniform distributed source in the inner central region. This result has applications to spherical deuterium tritium inertial confinement fusion targets.