cssi/SciSciGPT-SciSciNet huggingface dataset:
Astrophysics: Hidden chaos in cosmic order

“Galaxies, like elephants, have long memories,” says an influential article from the 1980s. Tapping into these memories has revealed some surprising facts about the history of our neighbouring Andromeda galaxy. A panoramic survey of the region around our nearest galactic neighbour, the well known Andromeda galaxy M31, has detected stars and coherent structures that are almost certainly remnants of dwarf galaxies destroyed by M31's tidal field. The brightest companion, the Triangulum galaxy (M33), is surrounded by a previously unknown prominent stellar structure that provides evidence for a recent encounter with M31. This new view of galactic structures is consistent with hierarchical cosmological models in which galaxies grow in mass by the accretion of smaller ones.
Exogenous Fungal Endophthalmitis

The authors report 19 cases of exogenous fungal endophthalmitis managed between 1969 and 1986. These developed after ocular surgery (5 cases), after trauma (6 cases), by intraocular spread from fungal keratitis (4 cases), after therapeutic keratoplasty for keratitis (3 cases), and by spontaneous infection of a filtration bleb (1 case). The diagnosis of endophthalmitis was made from 3 days to 4 months after surgery or trauma. In patients with preexisting keratitis, endophthalmitis was noted 2 weeks to 5 months after the onset of keratitis. Seventeen cases were caused by filamentous fungi; two were caused by yeast. Fusarium (6 cases) and Acremonium (3 cases) accounted for approximately one half of the isolates. Forty-two percent of the patients recovered 20/400 or better acuity (3 of 5 postoperative cases, 4 of 6 trauma cases, and 1 of 4 keratitis cases). The clinical and microbiologic features of these cases are presented, and recommendations for management are offered.
Analysis of clinical trials involving non-cavitated caries lesions.

Treatments to halt or reverse the progression of noncavitated caries lesions are of increasing interest. Diagnostic technologies under development offer potential for the assessment of gradual progression and regression of such lesions. Many therapies directed at correcting demineralization-remineralization imbalance should, in principle, protect enamel similarly across lesion severities from initiation to near cavitation. If this is so, and if acceptable reproducibility and predictive validity can be demonstrated for a diagnostic of acceptable cost, then clinical trials of agents to prevent cavitation can become more efficient by the use of outcome indices that reflect, in addition to cavitation, the expansion and regression of non-cavitated lesions. However, to achieve such a benefit will require data analyses that fully exploit ordinal or continuous-scale outcome measures. We consider comparison of such measures of lesion status between treatment groups, with most attention to ordinal categorical data....
Easterly waves over Africa. Part I: The seasonal cycle and contrasts between wet and dry years

Abstract The nature of African easterly waves (AEWs) and the easterly wave season over West Africa are examined using the National Centers for Environmental Prediction (NCEP) reanalysis. The study is carried out with two objectives in mind. The first goal is to describe the seasonal cycle of wave activity and to determine if it has a distinctive signature. To achieve this, the temporal evolution of wave period, amplitude, and structure are examined with wavelet analysis. This analysis is carried out at a grid point (15°N, 0°) that is at located where AEWs are well developed. The second goal is to determine differences in the wave characteristics and the wave season between wet and dry years. Regarding the seasonal cycle, it was found, in accordance with previous research, that AEW activity typically occurs between May and October. Disturbances have a periodicity between 4 and 8 days. At the level (600 mb) of the African easterly jet (AEJ) there was a broad peak in the magnitude of the variance over the mo...
Changes in catecholamine levels and turnover rates in hypothalamic, vocal control, and auditory nuclei in male zebra finches during development

The catecholamines norepinephrine (NE) and dopamine (DA) have been implicated in the sexual differentiation of brain and behavior and in species-specific learning in several species. To determine if these neurotransmitters might be involved in sexual differentiation of the vocal control system and song learning in male zebra finches, NE and DA levels and turnover rates were quantified in 10 behaviorally relevant brain nuclei [6 vocal control (VCN), 2 auditory (AN), and 2 hypothalamic (HN)] at four critical points during sexual differentiation of the VCN and the period of song learning, 25, 35, 55, and 90 days of age. Some birds were pretreated with α-methyl-para-tyrosine (αMPT) to allow estimation of NE and DA turnover rates. NE and DA levels in microdissected nuclei were quantified using high-performance liquid chromatography with electrochemical detection. αMPT treatment suppressed catecholamine synthesis just as effectively in juveniles as it does in adults and proved an effective method for estimating NE and DA turnover rates. Patterns of NE and DA function in most VCN and AN over development were quite different from those in HN in which NE and DA function changed gradually and showed no striking peaks. NE turnover rates changed significantly over development in all six VCN [nucleus interfacialis (Nlf), high vocal center (HVC), nucleus robustus of the archistriatum (RA), dorsomedial portion of the intercollicular nucleus (DM), Area X of the parolfactory lobe, and lateral portion of the magnocellular nucleus of the anterior neostriatum (IMAN)]; one AN [nucleus mesencephalicus lateralis pars dorsalis (MLd)], and one HN [preopticus anterior (POA)]. NE levels changed significantly in two VCN (Nlf and Area X). In Nlf, RA, Area X, IMAN, and MLd, NE levels and/or turnover rates showed a striking peak at day 25, which was not seen in HN. Both DA levels and turnover rates changed profoundly over development in 5 of 6 VCN (Nlf, RA, DM, Area X, and IMAN) and both AN (MLd and Field L). These nuclei showed striking peaks in DA levels and turnover rates, primarily on day 35 and/or 55, which then declined profoundly by day 90. This contrasted with the minimal change in DA turnover rates seen in one HN (POA) and the sixth VCN, HVC. In several VCN and AN, NE and DA levels and turnover rates during development reached levels never seen in adult males. Previous research has shown that catecholamine function is heightened in VCN during development compared to surrounding tissues. Our data demonstrate that NE and DA function during development shows pronounced peaks in most VCN not seen in HN. This is interesting because both VCN and HN are hormone sensitive, and both show hormone-modulated NE and DA function in adult males. The timing of these peaks suggests that increased catecholaminergic function may be involved in sexual differentiation of the VCN and song learning in finches. © 1998 John Wiley & Sons, Inc. J Neurobiol 34: 329–346, 1998
The Effect of Bovine Growth Hormone, Desoxycorticosterone Acetate, and Cortisone Acetate on the White Blood Cell Counts of 2-Week-Old Chickens

Abstract IN A recent paper by the author, Glick (1960a), bovine growth hormone was reported to stimulate the growth of the adrenals and bursa of Fabricius. Also, bovine growth hormone appeared to counteract the depressive influence of cortisone acetate on the size of the adrenals and bursa of Fabricius. One of the conclusions in this paper was that the bovine growth hormone acted directly on the adrenal glands without causing an increased release of glucocorticoids. The purpose of this experiment was to collect additional data concerning the relationship of bovine growth hormone injections and hormonal release by the adrenal gland in the chicken. PROCEDURE At hatching, fifty New Hampshire broiler-type chicks were equally divided into ten groups and placed in battery brooders. There were 3 males and 2 females in each group. Bovine growth hormone (.4 ml.), desoxycorticosterone acetate (.2 ml.), cortisone acetate (.05 ml.), all combinations of the three hormones…
A procedure for implementing the fast Fourier transform on small computers

A technique has been developed that adapts the Fast Fourier Transform algorithm for implementation on computers having relatively long multiplication times. The technique is particularly well suited to real-time processing on a small data acquisition computer such as the IBM System/7. Four basic ideas are utilized to improve the performance of the original Cooley-Tukey algorithm on such a machine: 1) The real-valued nature of the input data is exploited. 2) The number of multiplications that must be carried out is minimized at the expense of additions. 3) The calculations are performed in a carefully ordered sequence. 4) Special multiplication algorithms are used. This technique has reduced by more than an order of magnitude the time required to carry out 1024-point transformations on a small computer. A program is developed for calculating these transforms in real time on an IBM System/7 computer. With this program, a maximum sampling rate in excess of 10 kHz is obtained.
Theory of two-phase detonation—Part II: Structure

Abstract The structure of a two-phase steady detonation in a granulated solid propellant studied, and existence conditions for a one-dimensional, steady two-phase detonation are given. Ordinary differential equations from continuum mixture theory are solved numerically to determine steady wave structure. In the limiting case where heat transfer and compaction effects are negligible, the model reduces to two ordinary differential equations that have a clear geometrical interpretation in a two-dimensional phase plane. This two-equation model predicts results that are quite similar to those of the full model. This suggests that in the limited parameter space studied heat transfer and compaction are not important mechanisms in determining the detonation structure. It is found that strong and Chapman-Jouguet (CJ) detonation solutions with a leading gas phase shock and unshocked solid can be admitted, as can weak and CJ solutions with an unshocked gas and solid. As for one-phase materials, the CJ wave speed is the speed of propagation predicted for an unsupported, one-dimensional, two-phase detonation. It is predicted that there is no admissible CJ structure with a single leading gas phase shock and unshocked solid below a critical value of initial bulk density. This result cannot be predicted from equilibrium end state analysis. Thus it is concluded that it is essential to consider reaction zone structure when assissing potential solutions.
Local Labor Market Structure and Male Employment Stability in Large Metropolitan Areas

The stability of employment (total hours worked) is a critical (but sometimes ignored) variable in the stratification process in American society. This article analyzes the determinants of(log)hours worked for a sample of male household heads (taken from the Panel Study of Income Dynamics), who participated in the labor force for at least 49 weeks in 1976. After controlling for sample selection bias, the structural features of the labor market of residence were among the more important determinants of hours worked for black men. For example, black men worked more hours when they lived in service-oriented metropolitan areas, although this was not true of low-skilled black men. In addition, government participation in local labor and product markets stabilized the employment experiences of black men. For white men, their labor supply was chiefly determined by the status of their occupations and whether or not they received unemployment benefits. The theoretical and policy implications of these findings are ...
Thermoelectric Study of Cobaltous Oxide Defect Structure

The thermoelectric coefficient of cobaltous oxide was measured as a function of temperature and oxygen activity between 1000° and 1400°C. Results conform to ideal point defect theory at high temperature and high oxygen activity. Minority electrons are detected near the low-oxygen activity phase boundary. At low temperature and high oxygen activity, deviations from ideality are detected in that oxygen exponents of the hole concentration exceed that predicted by Ideal point defect theory.
In Vitro Leukocyte Endogenous Mediator Production Is Not Impaired following Surgical Stress in Moderately Malnourished Patients

Leukocyte endogenous mediator (LEM), a protein produced by phagocytizing cells, plays a critical role in the metabolic response to injury and infection. There is an important interaction between protein-calorie malnutrition and the capacity of cells to produce LEM, since severely malnourished or severely stressed individuals, have a reduced capacity to produce LEM. The leukocytes of 10 mildly to moderately malnourished patients undergoing elective major surgery, a moderate stress, had an intact ability to produce LEM on preoperative assessment. This ability was not affected by a 5-day postoperative period of hypocaloric nutrient intake despite a significant loss of body protein in one-half of the patients and a significant fall in serum protein concentrations. These results suggest a high biologic priority for LEM production during the metabolic response to injury and for infection. (Journal of Parenteral and Enteral Nutrition 8:174-177, 1984)
Integrating the Dirichlet-multinomial and multinomial logit models of brand choice

This paper discusses the interpretative benefits that arise from merging the Dirichlet-multinomial (DM) model as a loyalty variable in the multinomial logit (MNL) model of brand choice. The estimated parameters of this hybrid model compare favorably to those of a “pure” DM model (with no marketing mix variables) as well as those of a standard MNL model with an exponentially smoothed loyalty measure. The hybrid model offers an index of consumer heterogeneity and estimates of each brand's “preference share,” adjusted for the effects of price and promotional activities. We illustrate the unique interpretations offered by these parameters across four different product categories, showing how changes in heterogeneity (across categories or model specifications) are closely related to changes in the overall impact of marketing mix variables.
VALIDATION OF THE TRANSIENT STRUCTURAL RESPONSE OF A THREADED ASSEMBLY

This paper will demonstrate the application of model validation techniques to a transient structural dynamics problem. The problem of interest is the propagation of an explosive shock through a complex threaded joint that is a surrogate model of a system assembly. The objective is to validate the computational modeling of the key mechanical phenomena in the assembly, so that the component can be represented with adequate fidelity in the system-level model. A set of experiments was conducted on the threaded assembly where the acceleration and strain responses to an explosive load were measured on mass-simulators representing payloads. A significantly detailed computational model of the threaded assembly was also created. Numerical features that represent the important characteristics of the response were defined and calculated for both the experimental and computational data. Each step of the model validation process will be described as applied to this problem. Fundamental issues regarding the nature of model validation and the role of model validation in the engineering analysis process will also be discussed.
Cross-Border Interest Group Learning in Canada and the United States

Many of the most prominent US interest groups have formal or informal relationships with Canadian groups. Yet groups in the two countries often have little incentive to share political strategies – to learn from each other. This article proposes that such learning can take place only when four factors are present: a stable relationship with governmental institutions; the resources to acquire useful political information; shared issues of concern; and a sense of being part of a well-defined cross-border region. The presence of these factors can promote the creation of enduring group networks, which in turn make cross-border political learning possible. The article presents case studies of environmental and business organizations in the New England/Atlantic Canada region to show the relationship between these determinants.
Isolation of a nuclear ribonucleoprotein fraction from chick oviduct containing ovalbumin messenger RNA sequences

Abstract A method was developed for the isolation of a ribonucleoprotein fraction from chick oviduct nuclei that contains 70% of the pulse-labeled RNA. These fractions also contain about 1% of the nuclear DNA and have an average RNA to DNA ratio of about 4:1. The major nuclear RNP proteins of 32,000 M r are present along with many additional proteins including histories. However, polysomal proteins and major oviduct cytoplasmic proteins are absent. Nuclei from fully stimulated chick oviduct contain about 3000 copies of ovalbumin messenger RNA sequences of which about 200 are in the RNP complexes: these complexes have sedimentation coefficients of 30 to 350 S and are resistant to disruption by EDTA. The level of ovalbumin mRNA sequences in these complexes reflects the overall rate of synthesis of this RNA. Withdrawal of estrogen leads to a parallel decline of nuclear estrogen receptors and ovalbumin mRNA sequences in the RNP complexes and a subsequent loss of cytoplasmic ovalbumin mRNA about three hours later. The 300-fold decrease in the level of ovalbumin mRNA sequences in these complexes and the eightfold decrease in stability of cytoplasmic ovalbumin mRNA account for the 2500-fold decrease in the level of cytoplasmic ovalbumin mRNA observed during withdrawal. Upon stimulation with estrogen, the kinetics of reappearance of ovalbumin mRNA sequences in the RNP complexes apparently accounts for the accumulation of cytoplasmic ovalbumin mRNA. Thus the nuclear RNP has some of the properties expected of nascent RNP complexes. The levels of ovalbumin and conalbumin mRNA sequences increase in the nuclear RNP with markedly different kinetics: conalbumin mRNA sequences reach half maximum by 1.5 hours, whereas ovalbumin mRNA sequences in these complexes reach half maximum at about eight hours. In the analysis in the accompanying Appendix, we show that the immediate increase of conalbumin mRNA sequences in the nuclear RNP may be accounted for by interaction of the hormone receptor complex with a single regulatory site, whereas the delayed increase of ovalbumin mRNA sequences in the RNP may be due to a requirement for interaction of the hormone receptor complex with multiple regulatory sites.
Residual Supplier Model of Coarse Grains Trade

The influence of domestic agricultural policies on trade in agricultural commodities has been discussed at length by economists. Some have emphasized the interaction of policy-determined residual supplies and demands of all participants in world trade. For example, McCalla concludes, "Therefore, the international market in grains is the interaction of policy-induced residuals from national markets, and the principal objective is to export domestic instability" (McCalla 1980, p. 39). Other analyses have emphasized the role of the United States in world trade. In this context, the United States often has been described as the residual supplier. For example, Kelly Harrison, then general sales manager of the U.S. Department of Agriculture (USDA), presented the following view of the United States as the residual supplier:
Aspects of One-Stage Voting Rules

Under the assumption that voters have linear preference orders, this study investigates the propensity of simple weighted scoring rules to yield a winning alternative which is the same as the alternative if any which would win using a norm rule such as the simple-majority rule or the Borda rule. The scoring rules examined are of the types implemented by ballot instructions such as “vote for two of the following seven alternatives” and “indicate your first 1, second 2, and third 3 choices from the following list of ten candidates.” The results, which apply only to situations where one of a number of alternatives is to be chosen on the basis of a single ballot, may be useful in designing balloting and scoring procedures for these types of situations.
Preliminary analysis of shuttle multispectral radiometer data for Southern Egypt

The Shuttle Multispectral Infrared Radiometer (SMIRR) is a spectroradiometer covering the region from 0.5 to 2.5 microns in 10 channels that acquired data from spots 100 m in diameter along the subspacecraft ground track. It was flown aboard the second flight of the Space Shuttle Columbia, November 12-14, 1981. Data collected during orbit 16 over southern Egypt show that carbonate rocks, kaolinite, and possibly montmorillonite can be identified by their SMIRR spectral signatures and limited knowledge of the lithologic units present. Detailed analysis of SMIRR data for this area indicates that calcite, kaolinite, and montmorillonite rocks give rise to absorption features that result in characteristic 10 channel spectra.
Accounting for crime

Abstract The major aim of this paper is to explore how crime has been re-presented in the late 20th century. The work is part of broad critical accounting research. Accounting and issues regarding fraud are part of our complex social fabric: including issues of regulation, governance, economic crises, poverty, race, youth, politics, and class. We examine how crime is infused with these issues by revealing the statistics and strategies of managing crime outside the walls of Wall Street—in prisons—and inside the walls of Wall Street—white-collar crime. In revealing how the state, the media, and accounting have managed crime, we support the lineage of others who see crime as a social phenomena and as a social construction. We conclude in accepting the importance of assessing the power of institutions—including accounting—in creating reality and reconstructing the frailties and errors of humans. As we reflect on the resilience of accounting to maintain its role in the regulatory apparatus of business, and on the lack of significant change in power relations and in the distribution of wealth, it behooves accounting activists to work both within its terrain, and also with broader social movements in global justice.
Electron diffraction evidence of domain twinning in graphite-bromine single crystals

The in-plane electron diffraction pattern from single crystals of graphite-bromine intercalation compound has been interpreted in terms of a three-fold twinned monoclinic unit cell having in-plane lattice translations a=8.87 A, b=4.26 A, and the angle between them γ=103.9°, commensurate with the graphite lattice. The resulting twinned-domain model has been verified by observation of electron diffraction from individual domains.
Palæomagnetism of Sediments from the Colorado Plateau

ON the Colorado Plateau of Arizona and Utah there are exposed, as a result of erosion, sedimentary strata substantially undisturbed since deposition, representing almost every period of geological time. In the Grand Canyon of the Colorado River, for example, there are sediments ranging in age from the late Pre-Cambrian or Algonkian to the Permian, and in Zion Canyon and the Painted Desert Mesozoic sediments are found. Thus this part of the southwestern United States is ideal for palaeomagnetic work, and I had long wished to make a collection of rocks there for this purpose.
The impact of tobacco control policies on disparities in children's secondhand smoke exposure: a comparison of methods.

To examine the impact of cigarette excise taxes and smoke-free legislation on tobacco use among households with school-age children and adolescents as well as disparities in children’s secondhand smoke exposure. We compare the results from models using causal inference techniques to those from cross-sectional models. We linked families of 6–17-year-olds from the 2003 (N = 67,607) and 2007 (N = 62,768) contacts of the National Survey of Children’s Health with state-level cigarette excise taxes and smoke-free legislation total score (0 [none]–32 [very strong]) in 2001 and 2005. Parents reported whether anyone in the household used tobacco products. In adjusted causal inference models every $1.00 increase in cigarette excise tax between 2001 and 2005 was associated with a 4 percentage point decrease in household tobacco use between 2003 and 2007 (p = 0.008); however, there was no effect of smoke-free legislation on household tobacco use. Significant interactions revealed that cigarette tax increases were only associated with reductions in household tobacco use for parents of white children and, separately, lower income households. In contrast, in adjusted cross-sectional models, a higher smoke-free legislation total score was associated with a lower prevalence of household tobacco use. Stronger cigarette excise taxes decrease tobacco use among households with school-age children and adolescents, but smoke-free legislation at the state level does not change parental smoking. Since cross-sectional models cannot assess the direction of causality, evaluations should employ causal inference methods to help inform policy decisions to reduce disparities in adult smoking and, ultimately, protect children from secondhand smoke.
The effects of list-method directed forgetting on recognition memory

University of Illinois at Urbana-Champaign, Urbana, Illinois It is an almost universally accepted claim that the list-method procedure of inducing directed forgetting does not affect recognition. However, previous studies have omitted a critical comparison in reaching this conclusion. This article reports evidence that recognition of material learnedafter cue presentation is superior for conditions in which the material that preceded cue presentation was designated as to-be-forgotten. Because the absence of an effect of directed-forgetting instructions on recognition is the linchpin of the theoretical claim that retrieval inhibition and not selective rehearsal underlies that effect, the present results call into question the need to postulate a role for inhibition in directed forgetting.
Analysis of fatty acid ethyl esters in hair as possible markers of chronically elevated alcohol consumption by headspace solid-phase microextraction (HS-SPME) and gas chromatography-mass spectrometry (GC-MS)

Fatty acid ethyl esters (FAEE) are products of the nonoxidative ethanol metabolism, which are known to be detectable in blood only about 24h after the last alcohol intake. After deposition in hair they should be suitable long-term markers of chronically elevated alcohol consumption. Therefore, a method for the analysis of ethyl myristate, ethyl palmitate, ethyl oleate and ethyl stearate from hair was developed based on the extraction of the hair sample by a dimethylsulphoxide (DMSO)/n-hexane mixture, separation and evaporation of the n-hexane phase and application of headspace solid-phase microextraction (HS-SPME) in combination with gas chromatography-mass spectrometry (GC-MS) to the extract. For use as internal standards, the corresponding D(5)-ethyl esters were prepared. The HS-SPME/GC-MS measurements were automatically performed using a multi-purpose sampler. The detection limits of the FAEE were between 0.01 and 0.04ng/mg and the reproducibility was between 3.5 and 16%. By application of the method to hair samples of 21 fatalities with known heavy alcohol abuse 0.045-2.4ng/mg ethyl myristate, 0.35-13.5ng/mg ethyl palmitate, 0.25-7.7ng/mg ethyl oleate and 0.05-3.85ng/mg ethyl stearate were measured. For social drinkers (30-60g ethanol per week), the concentrations were about one order of magnitude smaller. For 10 teetotalers negative results or traces of ethyl palmitate were found. It was shown by supplementary investigations in single cases that FAEE are also present in sebum, that there is no strong difference in their concentrations between pubic, chest and scalp hair, and that they are detectable in hair segments after a 2 months period of abstinence. From the results follows that the measurement of FAEE concentrations in hair is a useful way for a retrospective detection of alcohol abuse.
Ultrastructure of Phytophthora megasperma f. sp. glycinea oospores parasitized by Actinoplanes missouriensis and Humicola fuscoatra

Transmission electron microscopy of hyperparasitism of Phytophthora megasperma f.sp. glycinea oospores by Actinoplanes and Humicola has shown that invasion occurred without appressorial or haustorial formation, and apparently without changes in oospore morphology or internal structure.
What should be the blood pressure target for diabetic patients

PURPOSE OF REVIEW: To summarize the pros and cons of a lower-than-usual blood pressure goal (e.g., <130/80 mmHg) for diabetic patients. RECENT FINDINGS: Aside from general socioeconomic and preventive medicine principles that either support or reject potential benefits associated with a lower blood pressure goal, clinical trial data from the last millennium have been challenged by the results of the prospective, randomized, National Institutes of Health-sponsored Action to Control Cardiovascular Risk in Diabetes trial, which found no significant benefit for a systolic goal of less than 120 mmHg, compared with less than 140 mmHg. Updated meta-analyses of five clinical trials are presented that show a significant (P < 0.05) reduction in the risk of stroke or major cardiovascular events. SUMMARY: Although a major clinical trial has shown that it is possible to lower blood pressure to a very low goal in a large number of diabetic patients, it remains to be seen whether those who are preparing the Eighth Report of the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure will agree with the American Diabetes Association and continue to recommend the less than 130/80 mmHg target for all diabetic patients.
Mechanism of Phospholipid Binding by the C2A-Domain of Synaptotagmin I†

Synaptotagmin I is a synaptic vesicle membrane protein that probably functions as a Ca2+ sensor in neurotransmitter release and contains two C2-domains which bind Ca2+. The first C2-domain of synaptotagmin I (the C2A-domain) binds phospholipids in a Ca2+-dependent manner similar to that of the C2-domains of protein kinase C, cytoplasmic phospholipase A2, and phospholipase Cdelta1. Although the tertiary structure of these C2-domains is known, the molecular basis for their Ca2+-dependent interactions with phospholipids is unclear. We have now investigated the mechanisms involved in Ca2+-dependent phospholipid binding by the C2A-domain of synaptotagmin I. Our data show that the C2A-domain binds negatively charged liposomes in an electrostatic interaction that is determined by the charge density of the liposome surface but not by the phospholipid headgroup. At the tip of the C2A-domain, three tightly clustered Ca2+-binding sites are formed by five aspartates and one serine. Mutations in these aspartate and serine residues demonstrated that all three Ca2+-binding sites are required for phospholipid binding. The Ca2+ binding sites at the top of the C2A-domain are surrounded by positively charged amino acids that were shown by mutagenesis to be also involved in phospholipid binding. Our results yield a molecular picture of the interactions between a C2-domain and phospholipids. Binding is highly electrostatic and occurs between the surfaces of the phospholipid bilayer and of the tip of the C2A-domain. The data suggest that the negatively charged phospholipid headgroups interact with the basic side chains surrounding the Ca2+-binding sites and with bound Ca2+ ions, thereby filling empty coordination sites and increasing the apparent affinity for Ca2+. In addition, insertion of hydrophobic side chains may contribute to phospholipid binding. This model is likely to be general for other C2-domains, with the relative contributions of electrostatic and hydrophobic interactions dictated by the exposed side chains surrounding the Ca2+-binding region.
Dolomitization by Ground-Water Flow Systems in Carbonate Platforms: ABSTRACT

Dolomite occurs throughout the subsurface of modern carbonate platforms such as the Bahamas. Groundwater flow systems must be responsible for delivery of reactants needed for dolomitization. Reflux, freshwater lens flows, and thermal convection are large-scale flow systems that may be widespread in active platforms. I have evaluated some End_Page 1219------------------------------ aspects of the dynamics and characteristics of these processes with ground-water flow theory and by scaled sandbox experiments. Reflux is not restricted to hypersaline brines, but can occur with bankwaters of only slightly elevated salinity such as those found on the Bahama Banks today (42 ^pmil). The lack of evaporites in a stratigraphic section, therefore, does not rule out the possibility that reflux may have operated. Flows associated with freshwater lenses include flow in the lens, in the mixing zone, and in the seawater beneath and offshore of the lens. Upward transfer of seawater through the platform margins occurs when surrounding cold ocean water migrates into the platform and is heated. This type of thermal convection ("Kohout convection") has been studied by Francis Kohout n south Florida. The ranges of mass flux of magnesium in these processes are all comparable and are all sufficient to account for young dolomites beneath modern platforms. Each process yields dolomitized zones of characteristic shape and location and perhaps may be distinguishable in ancient rocks. The concepts presented here may have application to exploration for dolomite reservoirs in the Gulf Coast and elsewhere. End_of_Article - Last_Page 1220------------
Minisequencing with acyclonucleoside triphosphates tethered to lanthanide(III) chelates

Four acyclic nucleoside triphosphates (derivatives of cytosine, thymine, 7-deazaadenine, and 7-deazaguanine) labeled with nonluminescent europium, terbium, dysprosium, and samarium chelates of 2,2',2'',2'''-[[4-(4-isothiocyanatophenyl)ethyl]pyridine-2,6-diyl]bis(methylenenitrilo)]tetrakis(acetic acid) were applied to minisequencing using two mutations (Delta F 508 and 1717-1 G to A) of cystic fibrosis as a model system. When synthetic targets were used, all four alleles involved could be analyzed in a single reaction using four terminating substrates labeled with four different lanthanide(III) chelates and DELFIA technology for detection. Blood spot samples without DNA isolations were used for PCR amplification and genotyping the target mutations by minisequencing. The single- and dual-labeled minisequencing assays were robust, while the four-label assay still requires further optimization of the multiplexed PCR amplification.
The devil’s in the details: evidence from the GED on large effects of small differences in high stakes exams

Abstract As part of standards-based educational reform efforts, more than 40 states will soon require students to achieve passing scores on standardized exams in order to obtain a high school diploma. Currently, many states are struggling with the design of their examination systems, debating such questions as which subjects should be tested, what should be the minimum passing scores, and what should be the rules regarding options for failing students to retake the exams. In this paper, we use data from a long-standing examination system, the General Educational Development (GED) exams, to illustrate the importance of the answers to these questions to both the number and composition of passers. We show that, among school dropouts in Florida and Texas who attempted the GED examinations, the option of retaking the examination upon initial failure was especially important for dropouts of color, and that the mathematics exam posed the greatest obstacle to females and the writing exam to males. We also show that an increase in the passing standard had a marked short-run impact on the number of school dropouts in Texas who attempted the GED exams, but that the number of test-takers recovered over several years.
Market linkages with fragmented production

Abstract I use a Ricardian model to analyze the transmission of technology shocks between countries when production processes are fragmented. The analysis emphasizes the role of three factors in determining how the gains from technical progress are shared between the innovating country and the rest of the world: the elasticity of substitution in consumption of final goods, the elasticity of substitution between intermediate and final production stages, and the pattern of production. In contrast to models with trade in final goods only, a high elasticity of substitution in consumption may be associated with losses for the innovating country when there is complete vertical specialization in production. I also examine the transmission of shocks in a three-country world where two countries are linked in a vertical production relationship.
Speciation of aryloxyethoxyethyl benzyl dimethyl ammonium salts by glass capillary gas chromatography and high-performance liquid chromatography

Abstract Using glass capillary gas chromatography (GC) and ion-pair reversed-phase high-performance liquid chromatography (HPLC), a pair of structurally similar microbicides, benzyl diisobutylphenoxyethoxyethyl dimethyl ammonium chloride and its cresoxy-analogue, were effectively resolved and accurately quantified with a high degree of selectivity and specificity. Optimization of conditions in the chromatographic systems to attain desirable baseline separations of the components of interest is described. The minimum detectable quantities as determined are in the neighborhood of 10 ng for the quaternary ammonium salts by HPLC-UV detection, 0.1 ng for the cyanamide derivatives of the salts by GC-alkaline flame-ionization detection and 1–2 pg for the trichloroethyl carbamate derivatives of the salts by GC-electron-capture detection. In conjunction with cation-exchange chromatography for sample enrichment and purification, the glass capillary GC and ion-pair reversed-phase HPLC methods presented here are particularly suitable to separate and simultaneously analyze for the aryloxyethoxyethyl benzyl dimethyl ammonium compounds concerned in environmental samples. It appears that these chromatographic techniques possess potential applicability to the separation and quantification of other classes of quaternary ammonium compounds with closely related structures that are not separable by other methods.
Proteinase inhibitor activity in connective tissues.

Extrakte verschiedener Bindegewebe wurden auf ihre Proteasehemmung hin elektrophoretisch untersucht. Alle Gewebe zeigten kationisch wandernde Aktivitat und ihre Anwesenheit im zellfreien Dentin lasst den Schluss zu, dass das Material extrazellular lokalisiert ist.
Functional properties of human ferroportin, a cellular iron exporter reactive also with cobalt and zinc

Iron homeostasis is achieved by regulating the intestinal absorption of the metal and its recycling by macrophages. Iron export from enterocytes or macrophages to blood plasma is thought to be medi...
Lesions and nodes of the thoracic inlet

The anatomy of the thoracic inlet and lesions of the thyroid gland, parathyroid glands, and brachial plexus are discussed in depth in other articles in this issue. The focus of this article is to review lesions of the remaining structures and spaces that abut or traverse through the plane of the thoracic inlet. Although this junction of the neck with the chest is relatively easy to define on coronal or sagittal MR, determining this level with axial CT and MR is actually a bit of a challenge. Depending on neck length, degree of neck extension, shoulder thickness, arm position, thoracic kyphosis, and scan angle, the appearance of this area is extremely variable. For the purpose of this article, the thoracic inlet is better regarded as a zone or volume extending several centimeters both above and below this plane. In addition, this zone is very prone to CT beam hardening artifacts from the thickness of the shoulders as well as MR pulsation, respiratory, and bulk susceptibility artifacts, often resulting in less than esthetic images.
Conditions that affect binding of DNA by cultured plant cells and protoplasts: An autoradiographic analysis

The binding of the14C-labelledSalmonella typhimurium DNA or3H-labelled soybean SB-1 DNA to cultured soybean cells (Glycine max L. Merr.) (SB-1) could be increased at least 100-fold by choosing the proper incubation conditions. The uptake of DNA by cells could completely be inhibited by the addition of an excess of unlabelled thymidine, indicating that the observed uptake of DNA by cells most probably is simply uptake of DNA degradation products. Autoradiograms, prepared from SB-1 protoplasts that were previously incubated with DNA, showed that the DNA was not associated with the protoplasts, but only with aggregates of cell wall material contaminating the protoplast preparation. When protoplasts and DNA were incubated in the presence of DEAE-dextran, the amount of DNAse resistant radioactivity increased 40 times. Again, the autoradiograms showed that most if not all DNAse-resistant material was associated with cell wall materials. Our observation that it is cell wall contaminants in protoplast preparations which account for most of the DNA binding demonstrates the need for caution in interpreting experiments on the binding and uptake of DNA by plant protoplasts.
Child Support, Fatherhood, and Marriage: Findings from the First 5 Years of the Fragile Families and Child Wellbeing Study

In this article, we review what has been learned to date from the first 5 years of the Fragile Families and Child Wellbeing study about child support, fatherhood, and marriage. The article first describes the parents’ circumstances at the time of the child’s birth, then examines the trajectories of parents’ relationships (with each other and others), fathers’ financial contributions and other indicators of fathers’ involvement with their children 5 years later; and finally reviews what has been learned about the effect of child support enforcement on these three aspects of families’ lives. We find that most unmarried parents are either cohabiting or romantically involved at the time of the child’s birth, but are a distinctly disadvantaged group as compared with married parents. Five years later, most of these parents are no longer romantically involved, however, most of the fathers are still seeing their children on a regular basis, and about half are contributing either formally or informally to their support. Strong child support enforcement appears to increase formal and decrease informal support from fathers, reduce marriage among parents, and have a weak positive effect on father involvement. More research is necessary to understand whether these findings are robust over time and across samples of unmarried parents.
Cryogenic ambient air vaporizers: frost growth, wind and seismic design for safety.

Abstract A popular method of vaporizing cryogenic industrial gases is to utilize the ‘free’ energy in the ambient air. This leads to very large free-standing vaporizer modules some now measuring up to 3 m × 3 m × 9 m high. As initially designed, catastrophic failures occurred due to excessive ice loading, thermal cycling, high wind loads and seismic forces. Faced with these failures, comprehensive design criteria and sound engineering practice are required to produce a safely operating ambient air vaporizer. This paper presents examples of actual operating failures and several present day module designs, and outlines the sound criteria for proper design now required for such equipment.
Synthesis and characterization of meso-[Ru(NO)Cl(dioxocyclam)] and the 1H NMR comparison with [MII(dioxocyclam)] complexes (MII=NiII and PdII) (dioxocyclam=1,4,8,11-tetraazacyclotetradecane-5,7-dione)

Abstract trans -[Ru(NO)X(dioxocyclam)], X=Cl − and OH − , dioxocyclam=(1,4,8,11-tetraazacyclotetradecane-5,7-dione) have been prepared and characterized by NMR, IR and ESI-MS techniques. The trans -[Ru(NO)Cl(dioxocyclam)] shows the nitrosyl stretch at 1846 versus 1875 cm −1 in the cyclam analogue, indicative of strong π-donation from the deprotonated dioxocyclam ligand to the Ru II center and, in turn, to the NO + group. Upon coordination, the dioxocyclam ligand no longer undergoes facile H/D exchange of the NH and C-6 protons. The methylene protons exist in symmetric patterns indicative of the meso isomer with both C-12 and C-14 methylene carbons projecting below the RuN 4 plane toward the side of the axial Cl − for the major product. A lesser amount of the rac isomer, wherein the C-12 and C-14 methylene carbons reside on opposite sides of the RuN 4 coordination plane, is detected. mmff 94 calculations determined that the meso form is more stable than rac by 3.33 kcal mol −1 . The Ru II –N(amide) bonds were calculated as having normal lengths (2.07 A), but the calculated Ru II –N(amine) bonds are elongated to 2.35 and 2.36 A. (It is known that molecular mechanics can overestimate bond lengths for second and third row metal centers by 0.10–0.15 A). Even after correcting for the over-calculated bond distance factor, it is seen that the amine–ruthenium distances are longer, and hence the bonds are weaker, than for ‘normal’ Ru II –amines. The presence of the axial Cl − is established by the ESI-MS ion fragments at m / z =394 for {d 2 -[Ru(NO)Cl(dioxocyclam)]H} + . Ions for {[Ru(NO)(H 2 O)(dioxocyclam)]} + ( m / z =377) and {[Ru(NO)(dioxocyclam)]} + ( m / z =359), the latter from loss of HCl or H 2 O from the 394 and 377 ions, are detected. 1 H and 13 C NMR data for meso -[Ru(NO)Cl(dioxocyclam)] are compared to the meso -[Pd II (dioxocyclam)] complex, and to the Ni II derivative that was synthesized at lower temperature than in previous literature reports. The meso -[Ni II (dioxocylam)] complex was identified previously. In the present work, it is shown that below 50°C the product for the Ni II system is rac -[Ni II (dioxocyclam)]. The assignments for the {Ru(NO)} 3+ , Ni II and Pd II dioxocyclam complexes as having the dominant isomeric forms as meso for {Ru(NO)} 3+ and Pd II , and rac for Ni II are supported by the H–H COSY spectrum for {RuNO)} 3+ , H–H and C–H COSY spectra for Ni II and the H–H COSY spectrum for Pd II derivatives.
Differential Effects of l-Dopa and Apomorphine on Glucagon Secretion in Man: Evidence Against Central Dopaminergic Stimulation of Glucagon

In 6 normal subjects, l-dopa (500 mg PO) and apomorphine (0.6 mg sc) increased circulating growth hormone and suppressed prolactin levels in a parallel and quantitatively similar fashion, but only l-dopa induced a rise in plasma glucagon, glucose, and insulin levels. The failure of apomorphine to affect glucagon secretion, despite a substantial effect on growth hormone and prolactin, was also observed in insulin-dependent diabetics known to exhibit A-cell hyperresponsiveness to various stimuli. In view of the highly dissimilar molecular and pharmacologic characteristics of l-dopa and apomorphine, these data do not exclude a local dopaminergic effect of l-dopa at the pancreatic level, but strongly militate against a central dopaminergic pathway for glucagon stimulation.
Adenoviral bronchopneumonia in an immunocompetent adult: computed tomography and pathologic correlations.

ABSTRACT Acute febrile lung disease associated with “patchy ground-glass pattern” on high-resolution computed tomography (HRCT) of the lung in an immunocompromised patient is suggestive of Pneumocystis carinii pneumonia; however, in an immunocompetent young person, it is suggestive of an atypical pneumonia, including viral bronchopneumonia. We studied a 31-year-old man who presented with fever, cough and hypoxemia. HRCT showed bilateral patchy ground-glass opacification. HIV test was negative and lung biopsy specimen grew adenovirus on viral culture. Histopathology of the lung was compatible with bronchopneumonia. In patients without HIV who present with acute lower respiratory infections and patchy ground-glass opacification on HRCT, adenoviral bronchopneumonia should be included in the differential diagnosis.