cssi/SciSciGPT-SciSciNet huggingface dataset:
Surgical Management of Morbid Obesity

Obesity imposes devastating health and financial tolls on society and those who suffer from it. Despite the growing awareness of the problem, the obesity epidemic, along with its associated complications, continues to expand at an alarming rate (1). The current nomenclature used to measure an individuals degree of obesity is BMI, which is calculated by dividing weight (in kilograms) by the square of height (in meters) (Table 1). Based on these criteria, the CDC (Centers for Disease Control and Prevention) reports a doubling of the obese population (BMI ≥30 kg/m2) in the period between 1976–1980 and 2001–2002 to reach an estimated number of 63 million obese people. Currently in the U.S., nearly two-thirds of adults are overweight (BMI >25 kg/m2), nearly one-third are considered obese (BMI ≥30 kg/m2), and 4.7% are extremely obese (BMI ≥40 kg/m2) (2). The financial cost of obesity in the U.S. is estimated to be in excess of $100 billion/year (3). In addition to increased risk of diabetes and other comorbid diseases, obese individuals may expect significant decreases in life expectancy (4) (Table 2). This obesity-related diminution in longetivity directly contributes to 280,000 deaths annually in the U.S. (5). Medical (nonsurgical) weight loss therapies include combinations of diet, exercise, behavioral therapies, and medications. In 1998, an NIH (National Institutes of Health) expert panel, upon critical review of the literature, concluded that these modalities, either alone or in combination, can induce modest weight loss that confers health benefits to the patients (6). However, the weight loss induced by these therapies is often short lived. Furthermore, medical management must continue indefinitely to be effective, or weight regain is common. Such medical therapies have not been shown to be effective in maintaining long-term weight loss in a morbidly obese patient population. Thus, most physicians …
An XAS study of the binding and reduction of Au(III) by hop biomass

Previous studies have shown that hop biomass is capable of adsorbing significant amounts of Au(III) from aqueous solutions. Hop biomass was chemically modified to determine the contributions that the different functional groups on the biomass have on the binding and reduction of Au(III). Previously, performed batch studies showed that Au(III) binding is fast, occurring within the first 5 min of contact and in a pH dependent manner. However, esterified hop biomass behaved in a pH independent manner and the binding was found not to change with changing pH. However, the hydrolyzed biomass had a similar Au(III) binding to the native hops biomass, showing a pH dependent binding trend. X-ray absorption spectroscopy (XAS) analysis, XANES (X-ray absorption near edge structure), and EXAFS (extended X-ray absorption fine structure) were used to determine the oxidation state, coordination environment, and the average radii of the gold nanoparticles bound to the hops biomass. The XAS data confirmed the presence of Au(0) in both the native and chemically modified hop biomasses. XANES fittings show that the Au(III) was reduced to Au(0) by approximately 81%, 70%, and 83% on the native, esterified, and hydrolyzed hop biomass, respectively. In addition, the calculation of the particle radius was also in agreement with the results of previously performed transmission electron microscopy studies. The average particle could only be calculated for the native and esterified hops biomass, which showed average particle radii of 17.3 A and 9.2 A, respectively.
Vertex-disjoint quadrilaterals in graphs

Let k be a positive integer and G a graph of order n. In (Discrete Math. 203 (1999) 229), we proved that if n=4k and @d(G)>=2k then G contains k-1 vertex-disjoint quadrilaterals. In this paper, we investigate vertex-disjoint quadrilaterals in G with n@?0(mod4), and we have found the best minimum degree condition @d(G)>=@?12n@? such that G contains @?14n@? vertex-disjoint quadrilaterals. As a result of our method, we have improved our previous result as follows: If n=4k and @d(G)>=2k-1 then G contains k-1 vertex-disjoint quadrilaterals.
Cooling molecules in a cell for FTMW spectroscopy

Gas phase benzonitrile, acetone, 1-2 propanediol, fluorobenzene, and anisole molecules are produced in a cell at a temperature of 8 K, and detected via Fourier transform microwave spectroscopy (FTMW). Helium buffer gas is used to cool the molecules originating from a high flux room temperature beam. This general, continuous source of cold molecules offers comparable spectral resolution to existing seeded pulsed supersonic beam/FTMW spectroscopy experiments but with higher number sensitivity. It is also an attractive tool for quantitative studies of cold molecule–helium and molecule–molecule elastic and inelastic collisions. Preliminary data on helium–molecule low temperature rotational and vibrational relaxation cross-sections are presented. Applications of the technique as a sensitive broad spectrum mixture analyser and a high resolution slow-beam spectrometer are discussed.
Simulation of cyber attacks with applications in homeland defense training

We describe a tool to help exercise and train IT managers who make decisions about IP networks in the midst of cyber calamity. Our tool is interactive, centered around a network simulation. It includes various modes of communications one would use to make informed decisions. Our tool is capable of simulating networks with hundreds of components and dozens of players. Test indicate that it could support an exercise an order of magnitude larger and more complex.
High level expression, purification, and characterization of the Kunitz-type protease inhibitor domain of protease nexin-2/amyloid β-protein precursor

The protease inhibitor, protease nexin-2 (PN-2), is the secreted isoform of the Alzheimer's amyloid β-protein precursor (AβPP) that contains the Kunitz-type protease inhibitor (KPI) domain. Here we describe the use of the methylotrophic industrial yeast Pichia pastoris as a host system for the large scale production of the KPI domain of PN-2AβPP. In addition to the 57 amino acid KPI domain, the expression product contained an additional four amino acid residues at its amino terminus that correspond to amino acids 285–288 of AβPP (Ponte et al. 1988 Nature 311:525–527). This expression system generated yields of greater than 1.0 gram of KPI domain per liter of fermentation media. The secreted 61 amino acid product was purified to homogeneity and biochemically characterized. Amino acid analysis and sequencing of the entire expressed KPI domain verified its integrity. Similar to native PN-2AβPP, the purified KPI domain potently inhibited trypsin, chymotrypsin, and coagulation factor XIa. Although heparin augments the inhibition of factor XIa by native PN-2AβPP it had no effect on the inhibition of factor XIa by expressed KPI domain suggesting that heparin binds to regions on native PN-2AβPP outside of the protease inhibitory domain. This KPI domain expression product should be useful in studying the physiologic and pathophysiologic functions of PN-2AβPP.
Atypical squamous metaplasia of seromas in breast needle aspirates from irradiated lumpectomy sites: A potential pitfall for false-positive diagnoses of carcinoma

The presence of squamous metaplasic cells is an uncommon finding in fine-needle aspiration (FNA) biopsies of the breast. We report that FNA smears containing atypical squamous metaplastic cells derived from the lining of seroma-type cavities following lumpectomy and irradiation in patients with breast cancer can be a potential pitfall for a false-positive diagnosis of recurrent malignancy. Four fine-needle breast aspirates from two adult patients with previous histories of invasive breast carcinoma were retrieved. One specimen was from a 56-yr-old female, while the remaining three FNAs aspirates were from a 75-yr-old female. Both patients presented with indurated cystic lesions arising at irradiated lumpectomy sites. The cytospins from the 56-yr-old patient showed markedly atypical cells having enlarged, degenerating, hyperchromatic nuclei and surrounding dense cytoplasm with sharp borders that were suspicious for carcinoma. A mastectomy revealed irradiation changes and atypical squamous metaplastic cells lining a cystic cavity consistent with a seroma, but there was no evidence of residual cancer. After three aspirations yielded "atypical" diagnoses, the second patient underwent core needle biopsies that also revealed changes consistent with a seroma cavity lined by atypical squamous metaplastic cells. We believe this is the first report of squamous metaplasia occurring in a seroma cavity following lumpectomy and irradiation of the breast. The squamous metaplastic cells in aspirates of these cystic lesions may display significant cellular atypia that can potentially result in a false-positive diagnosis of malignancy.
Zinc oxide nanowires for biosensing applications

In this work, we demonstrate the immobilization of carboxylic acid moieties on the surface of ZnO nanowires and its potential for biosensing applications. ZnO nanowires were synthesized via Chemical Vapor Deposition (CVD) technique and appropriately characterized. Vibrational spectroscopic techniques were used to determine nature of bonding and orientation of oleic acid molecule at nanowire surface, which is used as model system. Furthermore, on the basis of photoluminescence data on modified- and unmodified ZnO nanowires with oleic acid, a generic approach to sense biomolecules along with mechanism of sensing is proposed.
The Scientific Committee on Antarctic Research, the Antarctic Treaty and Conservation in Antarctica

Abstract A Symposium on Scientific Requirements for Antarctic Conservation was jointly sponsored by the International Union for the Conservation of Nature and Natural Resources (IUCN) and the Scientific Committee on Antarctic Research (SCAR), and was held in Bonn, Federal Republich of Germany in April 1985. IUCN and SCAR are different in scope of mission, criteria for membership, and financial resources in support of their activities. The two organizations find a common ground in conservation in the Antarctic, SCAR and the Antarctic Treaty came into being as a result of the 1957–1958 International Geophysical Year, and although the Consultative Parties of the Treaty and SCAR have no formal relationship, SCAR has responded to frequent requests from the Treaty nations for scientific information and advice related to the formulation of policy. Among these requests are those related to living resources of the Southern Ocean and the environmental effects of mineral resource exploration and exploitation. SCAR also recommended the adoption of principles for Antarctic conservation and the establishment of Sites of Special Scientific Interest and Specially Protected Areas. In most cases these recommendations have been implimented by the Consultative Parties. The role of the Consultative Parties was debated in the United Nations General Assembly where some members of the Third World Nations challenged the exclusivity of the Treaty Nations in the governance of Antarctica. They proposed instead that Antarctic affairs should be regulated under a UN trusteeship because Antarctica is “the common heritage of all mankind.” To explore this controversy in all its ramifications, an informal workshop was held in a remote site in Antarctica in January 1985. Participants included scientists, diplomats, international lawyers, environmental advocates, conservationists, and representatives from industry and the United Nations. The views of both the Consultative Parties and the Third World Nations were presented and informally debated at length. The conservation of Antarctic resources and the protection of the environment were two themes on which all agreed. The differences related to the manner in which conservation of resources and environmental protection should be carried out and under what authority.
Determination of Lipid Layer Thickness with Broadband Diffuse Optical Spectroscopy

Broadband Diffuse Optical Spectroscopy (DOS) measurements performed on the forearm of ten subjects with varying lipid layer thicknesses are correlated with skin fold calipers values to show that DOS can be used independently to measure lipid layer thickness.
High-magnetic-field magnetization and magnetoresistance of a transition-metal-base spin glass: Zr-Mn

The magnetization M and electrical resistivity rho have been measured at 0 T/sub 0/, high H >> k/sub B/T/g..mu../sub B/, Larkin-Khmel'nitskii (LK) prediction ..delta..M (LK) = ..delta..M/sub s/(1more » - H/sub 0//H) (..delta..M/sub s/ is the impurity saturation magnetization, H/sub 0/ proportional cV/sub 0/, V/sub 0/ is the RKKY coefficient) does not account for the (i) T-dependence of ..delta..M, (ii) relatively low fields 40 9 or approx. = H/sub s/ 9 or approx. = 130 kG (at 520 < or = c < or = 3100-ppm Mn) required for saturation of the impurity magnetization at 1.2 K; (f)« less
UnstructuringChinese Society: The Fictions of Colonial Practice and the Changing Realities of "Land" in the New Territories of Hong Kong

UnstructuringChinese Society: The Fictions of Colonial Practice and the Changing Realities of "Land" in the New Territories of Hong Kong. Allen Chun. Amsterdam: Harwood Academic Publishers, 2000. xi. 348 pp., tables, map, bibliography, appendix, index.
Dynamic constitutive behavior of Hastelloy X under thermo-mechanical loads

An experimental investigation has been conducted to study the dynamic constitutive behavior of Hastelloy X (AMS 5754) at room and elevated temperatures under varying rates of loading. A split Hopkinson pressure bar (SHPB) apparatus was used in conjunction with an induction coil heating system for applying dynamic loads at elevated temperatures. Experiments were carried out at different temperatures ranging from room temperature (25 °C) to 1,100 °C at an average strain rate of 5000/s. Room temperature experiments were carried out at varying strain rates from 1000 to 4000/s. The results show that as the strain rate increases from quasi-static to 4000/s, the yield strength increases by approximately 50%. Also, under dynamic loading, the yield stress decreases with temperature up to 700 °C, after which it shows a peak at 900 °C before beginning to decrease again as the temperature is further increased. The Johnson–Cook model was used to predict the dynamic plastic response under varying rates of loading and at different temperatures.
On the stability of obliquely propagating whistlers

By means of an energy conservation approach, this paper analyzes the growth rates of whistlers with arbitrary frequency and direction of propagation in a cold plasma permeated by a dilute energetic electron population. Numerical results are obtained for whistler frequencies and plasma characteristics prevailing at the onset of artificially stimulated emissions. It is found that the growth rates do not in general maximize for propagation along the static magnetic field, and a criterion for the existence of maximal growth at this direction is derived. An application to artificially stimulated emissions is discussed.
A new 3D mass diffusion---reaction model in the neuromuscular junction

A three-dimensional model of the reaction-diffusion processes of a neurotransmitter and its ligand receptor in a disk shaped volume is proposed which represents the transmission process of acetylcholine in the synaptic cleft in the neuromuscular junction. The behavior of the reaction-diffusion system is described by a three-dimensional diffusion equation with nonlinear reaction terms due to the rate processes of acetylcholine with the receptor. A new stable and accurate numerical method is used to solve the equations with Neumann boundaries in cylindrical coordinates. The simulation analysis agrees with experimental measurements of end-plate current, and agrees well with the results of the conformational state of the acetylcholine receptor as a function of time and acetylcholine concentration of earlier investigations with a smaller error compared to experiments. Asymmetric emission of acetylcholine in the synaptic cleft and the subsequent effects on open receptor population is simulated. Sensitivity of the open receptor dynamics to the changes in the diffusion parameters and neuromuscular junction volume is investigated. The effects of anisotropic diffusion and non-symmetric emission of transmitter at the presynaptic membrane is simulated.
African American Administrators in Community/Migrant Health Centers

Community and migrant health centers (CHC/MHCs) play a secondary role as avenues for the development of minority and women health care professionals, groups traditionally underrepresented in admin- istrative and managerial positions within the health care system. This paper focuses on the role of CHC/MHCs in eliminating the barriers that typically limit the professional advancement of these groups. In a survey of both rural and urban CHC/MHC administrators, it was found that CHC/MHCs have higher percentages of minorities in top management positions than general management but do not necessarily reflect the minority composition of those being served. Of the CHC/MHC adminis- trators, 10 percent were African American, less than the population served (31 percent) but greater than the percentage of African Americans in the general U.S. population (12 percent). This suggests that CHC/MHCs have partially met the original goal of upward mobility and that there is room for improvement.
Longitudinal dissociation within the posterior AV nodal input of the rabbit: a substrate for AV nodal reentry.

Background—Longitudinal dissociation of an anatomic pathway into 2 electrophysiologically distinct pathways has been hypothesized as a basis for localized AV nodal reentry and supraventricular arrhythmias. Methods and Results—Extracellular bipolar and intracellular microelectrodes were used to record activation in the superfused rabbit AV junction. A subset of rabbit hearts (n=19 of 72) demonstrated dissociation of the posterior AV nodal input into ≥2 functional pathways. Antegrade AH conduction was maintained by a pathway just inferior to the tendon of Todaro. Rate-dependent conduction block was observed in a second pathway just superior to the tricuspid annulus, allowing retrograde activation of the distal portion of the inferior posterior AV nodal input and leading to the formation of apparent “dead-end” pathways. The superior (antegrade) and inferior (retrograde) pathways were separated by a band of well-polarized but poorly excitable transitional cells. Additional decreases in the atrial cycle length...
Chemical vapor deposition of large area few layer graphene on Si catalyzed with nickel films

Abstract We present the results of a systematic study of chemical vapor deposition of graphene on silicon substrates. The silicon substrate is covered with SiO 2 and capped with an electron-beam evaporator deposited nickel film, which serves as the catalyst for carbon precursor decomposition. Methane is used as the carbon precursor. Three key parameters of CVD growths, the growth temperature, time, and the post-growth cooling rate are studied and the optimized combination of the three allowed for the reproducible fabrication of single layer graphene of larger than 100 μm 2 covering more than 50% of the surface of 1-in. diameter Si wafers. We further demonstrate the transfer of CVD graphene onto SiO 2 /Si surfaces with higher than 95% success rate. Our result together with those reported by other research groups shows real promise of the integration of carbon electronics with silicon integrated circuit technology.
Rhizobactin, a siderophore from Rhizobium meliloti

Abstract Iron is required at a number of stages in the biological fixation of dinitrogen. Environmental iron occurs in an oxidized and polymerized state which is quantitatively insoluble at biological pH. Consequently, most aerobic and facultative anaerobic microorganisms have evolved specific carriers, termed siderophores, for the dissolution and uptake of iron (III). We have investigated the symbiotic nitrogen fixing bacterium, Rhizobium meliloti DM4, for the presence of a siderophore system of iron assimilation. The bacterium when cultured on low‐iron media was observed to form a substance which corrects iron starvation imposed by the synthetic chelating agent ethylenediamine‐di‐(o‐hydroxyphenyl acetic acid) (EDDA). The compound, designated rhizobactin, was extracted and obtained in crystalline form. A structural analysis of rhizobactin by means of mass and nuclear magnetic resonance spectroscopic techniques indicates that it is not a member of either the catechol or hydroxamate type families of sidero...
Heterogeneity of hair cells in the bullfrog sacculus.

Morphometric and electrophysiological features of hair cells in the sacculus of the bullfrog (Rana catesbeiana) were studied. Confocal microscopy observations of hair cells in situ revealed that three classes of hair cells can be distinguished by their somata shape and macular location. Two of these, termed central cylindrical (CCHCs) and central flask-shaped (CFHCs) hair cells, were found in the central part of the macula. The third class, termed peripheral elongated hair cells (PEHC), was only found around the perimeter of the sacculus. Using the whole-cell patch-clamp technique CCHCs and CFHCs were distinguished by the amplitude of their voltage-activated calcium currents (ICa). The mean amplitudes of steady-state ICa at –20 mV were –900 ± 500 pA (n = 18) for CCHCs and –160 ± 70 pA (n = 10) for CFHCs. The two hair-cell types also differed in the possession of a Cs+-resistant, apamin-sensitive, calcium-sensitive potassium current, found only the CFHCs. This study indicates that several populations of hair cells with distinct morphological features exist in the bullfrog sacculus, and that at least two of these differ in their complement of membrane conductances.
Molecular Dynamics Simulations of Protein Unfolding and Limited Refolding: Characterization of Partially Unfolded States of Ubiquitin in 60% Methanol and in Water

Extensive experimental data are available on the native, partially and fully unfolded states of ubiquitin. Two and three-dimensional NMR experiments of a partially unfolded form of the protein in 60% methanol indicate that approximately one-half of the molecule contains disrupted but native-like structure while the other half is unstructured and/or contains non-native structure. In contrast, the interpretation of hydrogen-exchange data have led to the conclusion that this state is native-like. Thus, there are discrepancies between the experimental studies, or interpretations based on the data. We compare the results of molecular dynamics simulations, under varying conditions, with the experimental results. The simulations extend past 0.5 ns and include explicit solvent molecules: either pure water or 60% methanol. To begin with, ubiquitin was thermally denatured in water (at 498 K). Two particular structures, or "aliquots", during the unfolding process were selected for further study (60 and 198 ps). These structures were then simulated separately in water and 60% methanol at a lower and experimentally meaningful temperature (335 K). The conformations generated from the structure extracted later in the simulation contained significant amounts of non-native structure in the presence of methanol while satisfying both the NMR and hydrogen exchange data. In fact, clearly non-native regions of the structure yielded the desired protection from hydrogen exchange. In contrast, an earlier, more native-like, intermediate did not do as well at predicting the hydrogen-exchange behavior and was inconsistent with the NMR data. These data suggest that the results and interpretations using the different experimental techniques can be reconciled by a single state. This finding also brings into question the practice of interpreting protection to hydrogen exchange in terms of native secondary and tertiary structure, especially when one has weak patterns and low protection factors. When the partially unfolded states were placed in pure water, the protein collapsed and began to refold. Therefore, the desired solvent-dependent properties were observed: the partially unfolded conformations with increased exposure of hydrophobic residues remained expanded in methanol but collapsed in water as the non-polar groups minimized their exposure to solvent.
Nonskeletal peloidal precipitates in Upper Triassic reefs, Yukon Territory (Canada)

ABSTRACT Peloidal sediments and crusts form up to 75 percent of framework limestones in Upper Triassic reefs in the Yukon Territory. The peloids are spherical to irregular in shape, 20-250 µm in size, and are commonly surrounded by one or more rims of sparry calcite. The peloidal sediments occur in confined cavities and in open spaces between reef framebuilders; the peloidal crusts generally coat calcareous sponges and tabulozoans. Internal evidence suggests that the peloids are not detrital grains or fecal pellets, and comparisons with Mg calcite peloids and peloidal crusts in modern environments suggest that they are precipitates, possibly resulting from bacterial activity.
Evidence for ferromagnetism in alloys formed between uranium tetraboride and yttrium tetraboride

Experimental results are presented showing an apparent inducement of ferromagnetism in UB/sub 4/ by alloying this compound with nonmagnetic YB/sub 4/. The appearance of ferromagnetism in the UB/sub 4/- YB/sub 4/ alloy may be the result of an effective increase in the average U-U atom spacing in the lattice due to dilution by YB/sub 4/. (JRD)
Hate Crimes in the Workplace: Worker-to-Worker Victimisation and Policy Responses

This paper addresses the phenomenon of hate crimes in the workplace. While workplace crime has been given considerable attention, less attention has been given specifically to bias-motivated offences and policy recommendations within the work environment. Further, little attention has been given to the social psychological profiles of potential offenders and how such knowledge might be used in formulating policy within organisations to address bias-motivated worker-to-worker crime. This paper addresses the current state of knowledge concerning workplace hate crime, what characteristics might typify offenders, and the role organisations might take in risk, security and prevention.
Overexpression of Secretory Phospholipase A2 Causes Rapid Catabolism and Altered Tissue Uptake of High Density Lipoprotein Cholesteryl Ester and Apolipoprotein A-I

Plasma levels of high density lipoprotein (HDL) cholesterol and its major protein component apolipoprotein (apo) A-I are significantly reduced in both acute and chronic inflammatory conditions, but the basis for this phenomenon is not well understood. We hypothesized that secretory phospholipase A(2) (sPLA(2)), an acute phase protein that has been found in association with HDL, promotes HDL catabolism. A series of HDL metabolic studies were performed in transgenic mice that specifically overexpress human sPLA(2) but have no evidence of local or systemic inflammation. We found that HDL isolated from these mice have a significantly lower phospholipid and cholesteryl ester and significantly greater triglyceride content. The fractional catabolic rate (FCR) of (125)I-HDL was significantly faster in sPLA(2) transgenic mice (4.08 +/- 0.01 pools/day) compared with control wild-type littermates (2.16 +/- 0.48 pools/day). (125)I-HDL isolated from sPLA(2) transgenic mice was catabolized significantly faster than (131)I-HDL isolated from wild-type mice after injection in wild-type mice (p < 0.001). Injection of (125)I-tyramine-cellobiose-HDL demonstrated significantly greater degradation of HDL apolipoproteins in the kidneys of sPLA(2) transgenic mice compared with control mice (p < 0.05). The fractional catabolic rate of [(3)H]cholesteryl ether HDL was significantly faster in sPLA(2)-overexpressing mice (6.48 +/- 0.24 pools/day) compared with controls (4.80 +/- 0.72 pools/day). Uptake of [(3)H] cholesteryl ether into the livers and adrenals of sPLA(2) transgenic mice was significantly enhanced compared with control mice. In summary, these data demonstrate that overexpression of sPLA(2) alone in the absence of inflammation causes profound alterations of HDL metabolism in vivo and are consistent with the hypothesis that sPLA(2) may promote HDL catabolism in acute and chronic inflammatory conditions.
More than a sidekick: glia and homeostatic synaptic plasticity.

Homeostatic synaptic plasticity is thought to have a crucial role in stabilizing the activity of neurons and networks, but the mechanisms are poorly understood. In a recent study, Stellwagen and Malenka have shown that synaptic scaling can be induced by activity-dependent changes in release of the cytokine tumor necrosis factor-α (TNF-α) and, surprisingly, that the source of TNF-α is glia rather than neurons. In addition to provide insight into the mechanisms of homeostatic plasticity, these data argue for the first time for an equal partnership between glial cells and neurons in the generation of an important form of synaptic plasticity.
Lead isotopic compositions of South Sandwich Island volcanic rocks and their bearing on magmagenesis in intra-oceanic island arcs

Pb isotope ratios have been measured in 12 volcanic rocks from the South Sandwich Islands. The ranges are 206Pb204Pb = 18.51–18.66; 207Pb204Pb = 15.55–15.64; 208Pb204Pb = 38.42–38.64. In 207Pb204Pb-206Pb204Pb and 208Pb204Pb-206Pb204Pb correlation diagrams, the South Sandwich data plot distinctly above the fields for ocean ridge basalts, and yield trends showing apparent mixing with a sedimentary end member similar to South Atlantic pelagic sediments as reported by Chow and Patterson (1962) and this study. Armstrong and Cooper (1971) have likewise shown that volcanics from the Lesser Antilles show mixing trends with North Atlantic sediments in Pb isotope correlation diagrams. The North Atlantic sediments have distinctly higher 206Pb204Pb and 208Pb204Pb ratios compared to the South Atlantic sediments. The parallel relationships between sediments and volcanic island arc rocks of the North and South Atlantic provide strong evidence for a component of Pb from subducted sediments in the lavas of the west Atlantic basin. In contrast to these data, lavas from the Mariana Arc in the western Pacific show little or no component of Pb from pelagic sediments. The reason for the different behaviors in the two settings is speculative.
ASSESSING THE RELATIVE EFFICIENCY OF AIRCRAFT MAINTENANCE TECHNOLOGIES: AN APPLICATION OF DATA ENVELOPMENT ANALYSIS

This study focuses on discretionary maintenance strategies and their relationship to aircraft reliability, as measured by the percentage of scheduled flights delayed because of mechanical problems. The methodology of Data Envelopment Analysis is employed to identify the various strategies employed by the major airlines over the time period 1990-1994. Additionally, this methodology allows for a normative assessment as to which strategies are relatively efficient. Furthermore, the specific strategies utilized by efficient and inefficient airlines can be compared at a micro-level and thus quantifiable recommendations for the latter group can be suggested.
C-kit-positive gastric metastasis of lobular carcinoma of the breast masquerading as gastrointestinal stromal tumor

A 61-year-old woman with no significant past history underwent gastric biopsies demonstrating a strongly c-kit-positive epithelioid malignancy, initially thought to represent gastrointestinal stromal tumor (GIST). Subsequent clinical and immunohistochemical evaluation proved the neoplasm to represent metastatic lobular carcinoma. This case illustrates that although c-kit is highly specific and sensitive for GIST, its expression may occur in a variety of other neoplasms, some of which morphologically resemble GIST and may present in the gastrointestinal tract as metastases. Therefore, a review of other c-kit-positive lesions is also highlighted.
(Step)Parenting Attitudes and Expectations: Implications for Stepfamily Functioning and Clinical Intervention

Stepfamilies face many challenges. Research and clinical work with stepfamilies have tended to use the family systems or developmental perspectives, while overlooking how cognitive processes may influence stepfamily functioning. We fill this gap in the literature by analyzing a sample from the Relationship Evaluation (RELATE) questionnaire database to examine the influence of (step)parenting cognitions on stepparenting issues and relationship satisfaction. Results indicate that individuals who report placing top priority on their own biological children expect their stepchildren to be obedient to them, and those who believe that the children interfere with the new parental relationship report higher levels of stepparenting issues and lower levels of relationship satisfaction. Clinical implications and limitations are discussed.
Circadian rhythm of anaerobiosis in a polychaete annelid.

ALTHOUGH intertidal organisms which cannot breathe air must be regularly subjected to tidal conditions in which they must respire anaerobically, there are no known cases in which these or other animals reduce environmental conditions to the point at which they must respire anaerobically. Indeed such reduction of microhabitat conditions would not be expected because of the relative inefficiency of known anaerobic energy-generating pathways. This report describes a rhythm of alternating aerobic and anaerobic metabolism in the polychaete Nereis virens. The rhythm is circadian under low intensity constant illumination.
The growth of WI-38 cells in a serum-free, growth factor-free, medium with elevated calcium concentrations.

The growth of WI-38 cells in serum-free growth medium with and without hormone supplementation in the presence of elevated Ca2+ concentrations was investigated. At 5 mM CaCl2, WI-38 cells seeded at low density without serum or hormone supplementation showed up to a 12-fold increased in cell number at saturation density over that obtained at day 1. Saturation densities were comparable when either 5 mM CaCl2 or epidermal growth factor (1 mM CaCl2) was used in the presence of insulin, dexamethasone and transferrin. Combining suboptimal doses of epidermal growth factor and CaCl2 resulted in an additive effect on saturation density. Thus, nornal human diploid cells are capable of substantial growth in serum-free, hormone-free growth medium. In contrast, confluent cultures refed with the same medium are not responsive to elevated Ca2+ concentrations. In fact, elevated Ca2+ concentrations inhibited the proliferative response of confluent cultures to epidermal growth factor, but enhanced their response to the combined treatment of insulin, transferrin and dexamethasone.
State hospital social work staff: Role conflict and ambiguity

Relatively few social workers want to work in state psychiatric hospitals (Davis, Harris, Farmer, Reeves, & Segal, 1989; Horsley, 1989; Rubin & Johnson, 1984). One possible explanation is that positions are structured in ways that practitioners s e e as inappropriate, thereby making it hard to achieve results they value. Little is known however, about how job structure affects the professionals who are employed in these settings. The present study began when hospital administrators sought assistance in clarifying what they saw as confusing social work functions in the wake of an increased need for accountability and an increasing proportion of chronically impaired patients. In particular, care and therapy roles were problematic. Many staff members seemed unable to perform in a manner commensurate with their training and professional desires; "grumbling" was as common as it was hard to pinpoint. Supervisory staff therefore wanted information about how
SU‐E‐T‐211: Optical Fluorescence Monitoring during External Beam Radiation Therapy Using Cerenkov Emission as Excitation Source

Purpose: Cerenkov emission is induced when a charged particle travels faster than the speed of light in a given medium. The Cerenkov effect occurs in everyday radiation therapy of tissue, yet this phenomenon has never been quantitatively characterized. In this study, an investigation of high‐energy radiation from a linear accelerator was carried out, to quantify the induced Cerenkov emission in biological media. Furthermore, we demonstrate that the Cerenkov emission can excite a molecularly produced fluorophore, protoporphyrin IX (PpIX), embedded in biological phantoms. Methods: Electrons at 6–18 MeV energies and photons at 6 or 18 MV energies, from a linear accelerator, were used to induce Cerenkov emission in aqueous phantoms. First, a CMOS camera imaged a water tank in order to investigate the dose distribution of external beamradiation. Secondly, the fluorescent photosensitizer PpIX was mixed into the phantom. An optical fiber bundle, positioned at the phantom surface, collected the Cerenkov emission and the Cerenkov‐induced optical fluorescence. Results: Images acquired in a water tank clearly shows the cross section of the electron (or photon)beam at all energies using a dose rate of approximately 4Gy/min. As expected from the Cerenkov theory the intensity increases as the energy of the radiation increases. Spectra acquired, either with photons or electrons, reveal that the Cerenkov emission excites the PpIX molecule, leading to optical fluorescence in the red spectral region. Conclusions: The results here indicate that molecular fluorescence monitoring during external beamradiotherapy is possible. This could potentially be used as a tool for treatment assessment through the evaluation PpIX production from e.g. high‐grade glioma. This work has been funded by NIH grants RO1CA120368 and PO1CA084203.
Allosteric control of the RNA polymerase by the elongation factor RfaH

Efficient transcription of long polycistronic operons in bacteria frequently relies on accessory proteins but their molecular mechanisms remain obscure. RfaH is a cellular elongation factor that acts as a polarity suppressor by increasing RNA polymerase (RNAP) processivity. In this work, we provide evidence that RfaH acts by reducing transcriptional pausing at certain positions rather than by accelerating RNAP at all sites. We show that 'fast' RNAP variants are characterized by pause-free RNA chain elongation and are resistant to RfaH action. Similarly, the wild-type RNAP is insensitive to RfaH in the absence of pauses. In contrast, those enzymes that may be prone to falling into a paused state are hypersensitive to RfaH. RfaH inhibits pyrophosphorolysis of the nascent RNA and reduces the apparent Michaelis-Menten constant for nucleotides, suggesting that it stabilizes the post-translocated, active RNAP state. Given that the RfaH-binding site is located 75 A away from the RNAP catalytic center, these results strongly indicate that RfaH acts allosterically. We argue that despite the apparent differences in the nucleic acid targets, the time of recruitment and the binding sites on RNAP, unrelated antiterminators (such as RfaH and lambdaQ) utilize common strategies during both recruitment and anti-pausing modification of the transcription complex.
Self-esteem, social competence and psychopathology in boys without friends

Abstract Very little is known about relationships between children's self-reported self-esteem and their behavior. In order to evaluate this relationship, the Piers-Harris Self Concept (PHS) Scale was administered to 59 non-psychotic boys referred to an outpatient children's social skills program. The Child Behavior Checklist (CBCL; Achenbach & Edelbrock, 1983) was administered to the mother and the Pupil Evaluation Inventory (PEI; Pekarik, Prinz, Liebert, Weintraub & Neil, 1976) to the teacher. Social competence, as reflected in CBCL and PEI measures, and externalizing behavior, as measured by the CBCL Externalizing Behavior scale were positively related to self-esteem. Relationships to conceptions of self-esteem and implications for assessment of treatment outcome were discussed.
Dietrich receives 2010 G. K. Gilbert Award: Citation

[1] William E. Dietrich received the 2010 G. K. Gilbert Award at the 2010 AGU Fall Meeting, held 13–17 December in San Francisco, Calif. The award recognizes “a scientist who has either made a single significant advance or sustained significant contributions to the field of Earth and planetary surface processes, and who has in addition promoted an environment of unselfish cooperation in research and the inclusion of young scientists into the field.”
International variations in expected equity premia: Role of financial architecture and governance.

Abstract Estimates of ex-ante equity premia are important in planning investments in pension funds, life insurance pools, and for other long-term financial obligations or goals. However, while global cross-border investment positions and flows have been rising, there is little research on non-US ex-ante equity premia or on their determinants in a global setting. This paper uses data on a recent 8-year period from 33 countries and models simultaneously our estimate of the ex-ante equity premium as a dependent variable and our measure of financial architecture as an instrumental variable. We document that ex-ante equity premia are larger in countries that have a more bank-oriented financial architecture, are wealthier, and have better governance. These results are robust to alternative model specifications and estimation techniques. Given the importance of equity premia and financial architecture, these results should be of much interest to scholars, managers, regulators, and policy makers.
Finite element modeling approaches of human cervical spine facet joint capsule

The human cervical spine facet joint capsule was modeled using four nonlinear finite element approaches: slideline, contact surface, hyperelastic, and fluid models. Slideline elements and contact surface definitions were used in the first two models to simulate the synovial fluid between the articulating cartilages. Incompressible solid elements approximated the synovial fluid in the hyperelastic model. Hydrostatic fluid elements idealized the synovial fluid in the fluid model. The finite element analysis incorporated geometric, material and contact nonlinearities. All models were subjected to compression, flexion, extension, and lateral bending. The fluid model idealization better approximates the actual facet joint anatomy and its behavior than the gap assumption in the slideline and contact surface models, and the solid element simulation in the hyperelastic model.
Plasma selenium levels in patients with advanced upper gastrointestinal cancer

Plasma selenium levels were determined at various intervals during hospitalization of 71 patients with upper gastrointestinal and other malignancies. These patients often require frequent nutritional as well as surgical or medical intervention. Attempts were made to identify, evaluate, and compensate for numerous confounding variables at each of the 374 plasma selenium determinations. Selenium levels in stable patients who were neither receiving aggressive antineoplastic therapy, nor septic, nor taking corticosteroids and who had no clinically significant metabolic imbalance were then separately analyzed. In 55 stable patients selenium levels were 28% lower than those found in 20 normal controls (mean 61.8 micrograms/L, P less than 0.0005). An analysis of all the readings showed that selenium levels were substantially decreased by recent radiotherapy or sepsis, by regional tumor spread and increased tumor burden, and by intravenous and/or enteral hyperalimentation and intravenous lipids. In contrast to these findings, levels were relatively higher in patients with an adequate oral diet or with a lesser tumor burden. The comparison between selenium levels in stable and in aggressively treated or septic patients supports the importance of the relationship of nutrition to selenium levels in cancer patients.
Note---Estimating Geographic Customer Densities Using Kernel Density Estimation

This paper shows how kernel density estimation may be used to estimate flexibly the geographic distribution of customers in a market. In addition it shows how a density-based product positioning methodology may be applied to site selection, using the estimated geographic customer density to help locate a new or relocated store or distribution center. This application provides a conceptual basis for more complicated site selection and spatial demand models which might involve several predictor variables.
Developing a Critical Lens: Using Photography to Teach Sociology and Create Critical Thinkers

Sociology instructors strive not only to teach their students the essential aspects of sociology but also to help students develop their critical thinking abilities. One way to help students become better critical thinkers is to assign projects that encourage students to critically assess their world by relating the course content to their everyday world. This article details a photography project that has been assigned in lower level sociology courses at a four-year university and a community college. The project has been successful in encouraging students to develop their critical thinking skills and locate course material within the context of their everyday lived experiences. Examples from projects and a content analysis of 87 anonymous reflection papers demonstrate that the project allows students to (1) relate the course material to their everyday world, (2) engage in an intellectually challenging assignment, (3) critically examine their taken-for-granted worlds, and (4) have fun while completing a challenging academic exercise.
Alteration in Lung Particle Translocation, Macrophage Function, and Microfilament Arrangement in Monocrotaline-Treated Rats

Individuals with preexisting cardiopulmonary disease are thought to be more susceptible to acute episodes of particulate pollution resulting in increased morbidity and mortality. Our study was designed to evaluate particle fate and macrophage function in an animal model of monocrotaline (MCT)-induced pulmonary hypertension. Two weeks following a single MCT injection, Sprague-Dawley rats were exposed sequentially to two different colored fluorescent microspheres 1.0 micron in diameter by aerosolization. Morphometric evaluation of lung sections was performed 0 and 24 h following the final particle exposure to determine the intrapulmonary location of inhaled microspheres. A decrease in the number of particles phagocytized by alveolar macrophages and an increase of free particles overlying the epithelium were found in MCT-treated animals compared with control. Pulmonary macrophages recovered by bronchoalveolar lavage were evaluated for chemotactic and phagocytic ability. Macrophage chemotaxis was significantly impaired following MCT treatment compared with controls, whereas phagocytic activity of macrophages lavaged from MCT and control treatment groups was similar. Macrophages were stained for filamentous (F) and globular (G) actin using Texas-Red-labeled phalloidin and Oregon-green-labeled DNase I, respectively. The area of microfilament staining for F and G actin increased, but the ratio of F/G actin was significantly decreased in animals with MCT treatment compared with control. While the responses observed with MCT treatment, such as pulmonary edema, polymorphonuclear leukocytes influx, and unique macrophage morphology may contribute to impaired macrophage function, the change in microfilament arrangement suggests that MCT may inhibit macrophage chemotaxis and impair particle clearance from the lungs.