cssi/SciSciGPT-SciSciNet huggingface dataset:
UV Raman spectroscopic studies of V/θ-Al2O3 catalysts in butane dehydrogenation

To explore the coke formation mechanism and catalyst structure under alkane dehydrogenation (DH) conditions, the DH of butane on V/θ-Al2O3 was explored by in situ UV Raman spectroscopy and reactivity tests. Studies of butane DH on V/θ-Al2O3 catalysts with various distributions of surface VOx species identify a structure–coke relationship. The deactivation of the catalysts in butane DH is due mainly to the formation of coke species. Both the nature and amount of coke formed are related to the structure of VOx species. Monovanadates make chain-like polyaromatics, whereas polyvanadates produce mainly sheet-like (two-dimensional) polyaromatics that are detrimental to catalytic activity. The amount of coke formed from butane DH follows this sequence: polymeric VOx > monomeric VOx > V2O5, Al2O3. Raman spectroscopy studies of butane, 1-butene, cis/trans-2-butenes, and 1,3-butadiene reactions on V/θ-Al2O3 catalysts enable the formulation of a coke formation pathway for butane DH, in which polystyrene is found to be a key intermediate. Although the surface of V/θ-Al2O3 is partially reduced under butane DH conditions, the structure of VOx species can be fully regenerated by oxidation of the coke species at temperatures up to 873 K.
Detecting CO2-induced temperature changes in the stratosphere

Abstract The interannual variability of the monthly and zonally averaged temperatures is calculated from seven years of global tropospheric and stratospheric analyses for January and July. The minimum detectable change in the mean temperature between the observations to date and observations of a future period of similiar length is calculated. The observed variability of the summer stratosphere is found to be substantially larger than that found in a three-dimensional model simulation as is the resulting minimum detectable change. The model is used to calculate the expected change from a doubling of the CO 2 concentration and the minimum CO 2 increase required to produce a dectectable temperature change.
Uncertainty, Isomorphism, and the Birth of a New Industry: Regulatory Policy Development in a New Health Services Sector, 1994-2004

The regulation of assisted living in the United States calls out for the attention of policy researchers, particularly in light of projected demographic changes reflecting dramatic increases in the...
Juvenile hormone bisepoxide biosynthesis in vitro by the ring gland of Drosophila melanogaster: a putative juvenile hormone in the higher Diptera

The in vitro production of juvenile hormone (JH) was investigated by using isolated ring glands from third instar Drosophila melanogaster. A JH-like molecule is secreted that comigrates with a synthetic sample of methyl 6,7;10,11-bisepoxy-3,7,11-trimethyl-(2E)-dodecenoate (JHB3) during TLC, liquid chromatography, and GC analysis. Purified product from farnesoic acid-stimulated ring glands was analyzed by electron impact GC/MS and gave a mass spectrum identical to synthetic JHB3. Additional structure confirmation was obtained following conversion of product from unstimulated biosynthesis to a derivative that comigrated on liquid chromatography with the derivative prepared from synthetic JHB3. Physiological studies revealed that JHB3 is produced solely by the corpus allatum portion of the ring gland in vitro. Isolated ring glands from other cyclorrhaphous dipteran larvae also produce JHB3 almost exclusively in vitro. Corpora allata from mosquito larvae, however, produce only JH III, indicating that JHB3 production may be restricted to the higher Diptera. Topically applied synthetic JHB3 caused developmental responses in newly formed D. melanogaster white puparia similar to those obtained with JH III. The data suggest that JHB3 is a fly juvenile hormone.
Application Of Photosensitive Material For Deformation And Vibration Analysis Of Structures Using Objective Laser Speckles

By illuminating a ground glass with a laser beam, a spatial field of speckles is created. These speckles are used as surface strain or displacement gauging elements of structures under static and vibrational deformation by coating the structural surface with photosensitive material. Equations used in obtaining the strain and displacement are shown.© (1983) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Receptor-associated protein: a specialized chaperone and antagonist for members of the LDL receptor gene family

Members of the LDL receptor gene family mediate cellular uptake of various extracellular ligands, including lipoprotein particles. Ligand interactions with these receptors can be antagonized by a 39 kDa receptor-associated protein. Recent biochemical, cellular, and genetic studies have shown that receptor-associated protein is a molecular chaperone/escort protein for LDL receptor-related protein, a member of the LDL receptor gene family that binds multiple ligands. These studies indicate that receptor-associated protein interacts with LDL receptor-related protein at multiple sites and assists the proper folding and disulfide bond formation of LDL receptor-related protein within the endoplasmic reticulum. Following the completion of folding, receptor-associated protein remains associated with the receptor during its subsequent trafficking along the early secretory pathway, thereby preventing premature ligand interaction with the receptor. The ability of receptor-associated protein to universally inhibit ligand interactions with members of the LDL receptor gene family underscores the use of this protein as a tool in the study of ligand-receptor interactions.
Metaplectic Anyons, Majorana Zero Modes, and their Computational Power

We introduce and study a class of anyon models that are a natural generalization of Ising anyons and Majorana fermion zero modes. These models combine an Ising anyon sector with a sector associated with $SO(m)_2$ Chern-Simons theory. We show how they can arise in a simple scenario for electron fractionalization and give a complete account of their quasiparticles types, fusion rules, and braiding. We show that the image of the braid group is finite for a collection of $2n$ fundamental quasiparticles and is a proper subgroup of the metaplectic representation of $Sp(2n-2,\mathbb{F}_m)\ltimes H(2n-2,\mathbb{F}_m)$, where $Sp(2n-2,\mathbb{F}_m)$ is the symplectic group over the finite field $\mathbb{F}_m$ and $H(2n-2,\mathbb{F}_m)$ is the extra special group (also called the $(2n-1)$-dimensional Heisenberg group) over $\mathbb{F}_m$. Moreover, the braiding of fundamental quasiparticles can be efficiently simulated classically. However, computing the result of braiding a certain type of composite quasiparticle is $# P$-hard, although it is not universal for quantum computation because it has a finite braid group image. This a rare example of a topological phase that is not universal for quantum computation through braiding but nevertheless has $# P$-hard link invariants. We argue that our models are closely related to recent analyses finding non-Abelian anyonic properties for defects in quantum Hall systems, generalizing Majorana zero modes in quasi-1D systems.
The Economic Cost of Farm Tractor Rollover Deaths in New York

: Farm tractor rollovers account for one quarter of all fatal farm injuries, but their economic impact has not been studied previously. This study surveyed surviving family members of people killed between 1985 and 1987 in New York farm tractor rollovers and found the average expected income lost by each death was $243,615 (response rate=46%, N=12). Fatal farm tractor rollovers may cost New York more than $2 million a year in lost income. Nonfarmers account for 33 percent of these rollover deaths. These nonfarmers were not on a farm and were not doing farm work at the time of the fatal injury. Policy responses to the dangers of farm tractors should consider the risks to nonfarmers and should be cognizant of the costs that could be averted.
Effects of Azoxystrobin Application Rate and Treatment Interval on the Control of Rhabdocline pseudotsugae on Douglas-fir Christmas Trees

Rhabdocline needlecast caused by Rhabdocline pseudotsugae is the primary disease limiting Douglas-fir Christmas tree production in the northeastern United States. Azoxystrobin (Quadris) was recently registered for control of needlecasts on conifers, but little is known about its efficacy. In 2002, azoxystrobin was applied to field-grown Lincoln N.F. Douglas-fir Christmas trees at 0.14 or 0.28 g a.i./liter as the first or second spray of a chlorothalonil-based control program. In 2003, four sequential sprays of azoxystrobin at 0.28, 0.55, and 1.10 g a.i./liter were compared to chlorothalonil treatments. Untreated trees at both Pennsylvania test sites in both years were heavily infected, confirming high inoculum levels and environmental conditions favorable for infection. The standard program that consisted of 1.29 g a.i./liter chlorothalonil applications was very effective in controlling Rhabdocline in all experiments. In 2002, application interval had a significant effect on efficacy. Trees sprayed with 0.14 and 0.28 g a.i./liter azoxystrobin 9 days prior to an infection period had a higher disease index rating than those sprayed 2 days prior to the same infection period. Application rate did not appear to have an effect on efficacy. Trees receiving 1.10 g a.i./liter azoxystrobin had the same disease index rating as trees receiving the 0.28 g a.i./liter rate. In all cases, azoxystrobin treatments had significantly higher infection rates than the standard chlorothalonil treatment. The level of natural inoculum present at each site also appeared to play a role in azoxystrobin efficacy. Azoxystrobin is more than twice the cost of chlorothalonil and the data presented does not support any cost incentive for its inclusion in a Rhabdocline control program.
Regional distribution of blood flow at the onset of right ventricular diastolic collapse during cardiac tamponade

Abstract The onset of right ventricular diastolic collapse has been shown to be a very sensitive and specific sign of cardiac tamponade in both clinical and consclous canine studies, and is associated with a decline in cardiac output of about 20%. To determine if blood flow to critical regions was affected at the time of onset of right ventricular diastolic collapse, seven unanesthetized, chronically instrumented dogs were studied during cardiac tamponade induced by the intrapericardial infusion of warm saline solution. Aortic blood pressure, heart rate, and cardiac output (electromagnetic flowprobe) were recorded at baseline (drained pericardial space) and at the onset of right ventricular diastolic collapse as seen on two-dimensional echocardiography. Regional blood flow was measured with radionuclide-labeled microspheres. Despite the expected decline in cardiac output, there was no significant change in cardiac, ronal, or cerebral cortical blood flow at the onset of right ventricular diastolic coliapse. Therefore, this noninvaslve marker of early cardiac tamponade begins before vital organ perfusion is compromised, thus strengthening its clinical value.
Atomic absorption spectrometric determination of copper, zinc, and lead in geological materials

Abstract An atomic absorption spectrometric method is described for the determination of copper, zinc, and lead in geological materials. The sample is digested with HF—HCl—H 2 O 2 ; the final solution for analysis is in 10 % (v/v) HCl. Copper and zinc are determined directly by aspirating the solution into an air—acetylene flame. A separate aliquot of the solution is used for determination of lead; lead is extracted into TOPO-MIBK from the acidic solution in the presence of iodide and ascorbic acid. For a 0.50-g sample, the limits of determination are 10–2000 p.p.m. for Cu and Zn, and 5–5000 p.p.m. for Pb. As much as 40 % Fe or Ca. and 10 % Al, Mg, or Mn in the sample do not interfere. The proposed method can be applied to the determination of copper, zinc, and lead in a wide range of geological materials including iron- and manganese-rich, calcareous and carbonate samples.
Regulation of isocitrate metabolism in peroxisomes in Tetrahymena pyriformis.

Abstract Isocitrate dehydrogenase (NADP + -dependent) and isocitrate lyase compete for substrate in peroxisomes (microbodies) in the ciliated protozoan Tetrahymena pyriformis . Thus, some of the factors that might regulate the metabolism of isocitrate in Tetrahymena peroxisomes were studied. The dehydrogenase has a much greater affinity for isocitrate than does the lyase, but is subject to a concerted feedback inhibition by oxalacetate and glyoxylate. Concentrations of 25 μ m of each cause almost complete inhibition. The degree of inhibition is greatly reduced unless NADP is present during a brief preincubation of the enzyme with the inhibitors. Either glyoxylate or oxalacetate alone is also capable of inhibiting the enzyme, although higher concentrations are required. In this case, there is no inhibition unless inhibitor and enzyme are preincubated in the presence of NADP. Neither the concerted inhibition nor that due to oxalacetate seems to be competitive with isocitrate. Properties of the enzyme from the soluble fraction of the cell were identical to those of the peroxisomal enzyme. Enzyme from mouse liver exhibited most of the properties observed with the Tetrahymena enzyme. The concerted inhibition of isocitrate dehydrogenase may be the means by which isocitrate in the peroxisome is shunted through the glyoxylate bypass.
Duplex-assisted internal carotid artery balloon angioplasty and stent placement : A novel approach to minimize or eliminate the use of contrast material

Background Carotid artery balloon angioplasty and stenting (CBAS) is emerging as an acceptable alternative to carotid endarterectomy in selected high-risk patients. Conversely, patients with pre-existing renal impairment, diabetes, or both may be harmed by the nephrotoxic contrast agents required during CBAS. We attempted to limit or eliminate the use of contrast material during CBAS. Methods Eighteen patients with severe carotid stenoses (>70%) underwent CBAS at our institution over the last 12 months with duplex scan-assisted CBAS. Of these, 12 were primary procedures, and 6 were performed for carotid re-stenosis. Fourteen patients (78%) were neurologically asymptomatic. The average age of these patients was 75 ± 11 years (range, 44–92 years). Hypertension, chronic renal insufficiency (serum creatinine level ≥1.5 mg/dL), coronary artery disease, diabetes, and smoking were present in 89%, 67%, 59%, 33%, and 28% of patients, respectively. Preoperative duplex carotid mapping was performed in all cases. All procedures were performed with patients under local anesthesia and light sedation. Results An ATL HDI 5000 scanner with the SonoCT feature was used. The common femoral artery was cannulated with a single-entry needle under direct ultrasound visualization. Fluoroscopy was used to assist passage of the guidewire into the aorta and the common carotid artery. In only four cases (22%) was an aortic arch angiogram obtained. Selective catheterization of the internal and external carotid arteries was performed under ultrasound guidance. The distal cerebral protection device (17 cases) was placed under fluoroscopic guidance. Balloon width and length were chosen according to ultrasound measurements. Balloon and stent deployment were successfully achieved with ultrasound guidance alone in all cases. Appropriate stent apposition and resolution of the stenosis was confirmed by duplex scanning in all cases. Five patients (28%) were noted to have low ( Conclusions Duplex scan-assisted CBAS is feasible and may reduce the need for intra-arterial contrast injection in selected patients deemed at high risk for renal failure from nephrotoxic contrast material. Additional advantages include direct visualization of the puncture site, precise position of the balloon and stent, and B-mode and hemodynamic confirmation of the adequacy of the technique.
Faith, Aging, and Dementia Experiences of Christian, Jewish, and Non-Religious Spousal Caregivers and Older Adults

Research consistently documents positive relationships among religion, spirituality, and outcomes related to well-being. The purpose of this study was to determine the degree to which spousal dementia caregivers and other older adults rely on religion and spirituality as coping resources. A total of 52 Christian, Jewish, and non-religious dementia caregivers - as well as matched comparison groups of non-caregivers - were interviewed. Qualitative data analysis yielded both common themes among the three religious groups as well as themes of distinction. The findings suggest that the search for meaning and purpose during stressful life events knows no religious or spiritual borders. Even among the non-religious and non-spiritual, purpose and meaning were found in other areas, including in caring for others, in friendships, or simply in the aesthetic joys of life.
Characterization of the p125 subunit of human DNA polymerase delta and its deletion mutants. Interaction with cyclin-dependent kinase-cyclins.

Abstract The catalytic subunit of human DNA polymerase (pol) δ was overexpressed in an active, soluble form by the use of a baculovirus system in insect cells. The recombinant enzyme was separated from endogenous DNA polymerases by phosphocellulose, Mono Q-Sepharose, and single-stranded DNA-cellulose chromatography. Recombinant DNA pol δ was also purified by immunoaffinity chromatography. The enzymatic properties of the purified catalytic subunit were characterized. The enzyme was active and possessed both DNA polymerase and associated 3′ to 5′ exonuclease activities. NH2-terminal deletion mutants retained polymerase activity, whereas the core and COOH-terminal deletion mutants were devoid of any measurable activities. Coinfection of Sf9 cells with recombinant baculovirus vectors for pol δ and cyclin-dependent kinase (cdk)-cyclins followed by metabolic labeling with 32Pi showed that the recombinant catalytic subunit of pol δ could be hyperphosphorylated by G1 phase-specific cdk-cyclins. When cdk2 was coexpressed with pol δ in Sf9 cells, pol δ was found to coimmunoprecipitate with antibodies against cdk2. Experiments with deletion mutants of pol δ showed that the NH2-terminal region was essential for this interaction. Coimmunoprecipitation and Western blot experiments in Molt 4 cells confirmed the interactionin vivo. Preliminary experiments showed that phosphorylation of the catalytic subunit of pol δ by cdk2-cyclins had little or no effect on the specific activity of the enzyme.
Any Teacher a Writing Teacher? The Value of “Free Writing”

In my work with faculty and teaching assistants from various disciplines, I often hear concern about the level of writing skills which students display in exams and papers. Unfortunately, a common assumption is that it takes an English teacher to deal with writing problems ?and besides, "I have enough problems just getting through my course material." The activities described below allow teachers to do something to improve their students' writing skills, and they don't involve sacrificing class time to teach some thing else ("English"). In addition, these strategies may be used to promote and focus group discussions, to assess the state of students' understanding, to encourage (with regular use) the students' coming to class prepared, or to help ensure that students have some grasp of the activities they are about to do (e.g., in a laboratory).
Carbon Dioxide Clathrate in the Martian Ice Cap

Carbon dioxide clathrate in Martian ice cap suggested from hydrate stability relative to solid phase and water ice as function of temperature
B-cell lymphomas with concurrent MYC and BCL2 abnormalities other than translocations behave similarly to MYC/BCL2 double-hit lymphomas

Large B-cell lymphomas with IGH@BCL2 and MYC rearrangement, known as double-hit lymphoma (DHL), are clinically aggressive neoplasms with a poor prognosis. Some large B-cell lymphomas have concurrent abnormalities of MYC and BCL2 other than coexistent translocations. Little is known about patients with these lymphomas designated here as atypical DHL. We studied 40 patients of atypical DHL including 21 men and 19 women, with a median age of 60 years. Nine (23%) patients had a history of B-cell non-Hodgkin lymphoma. There were 30 diffuse large B-cell lymphoma (DLBCL), 7 B-cell lymphoma, unclassifiable, with features intermediate between DLBCL and Burkitt lymphoma, and 3 DLBCL with coexistent follicular lymphoma. CD10, BCL2, and MYC were expressed in 28/39 (72%), 33/35 (94%), and 14/20 (70%) cases, respectively. Patients were treated with standard (n=14) or more aggressive chemotherapy regimens (n=17). We compared the atypical DHL group with 76 patients with DHLand 35 patients with DLBCL lacking MYC and BCL2 abnormalities. The clinicopathologic features and therapies were similar between patients with atypical and typical DHL. The overall survival of patients with atypical double-hit lymphoma was similar to that of patients with double-hit lymphoma (P=0.47) and significantly worse than that of patients with DLBCL with normal MYC and BCL2 (P=0.02). There were some minor differences. Cases of atypical double-hit lymphoma more often have DLBCL morphology (P<0.01), less frequently expressed CD10 (P<0.01), and patients less often had an elevated serum lactate dehydrogenase level (P=0.01). In aggregate, these results support expanding the category of MYC/BCL2 DHL to include large B-cell lymphomas with coexistent MYC and BCL2 abnormalities other than concurrent translocations.
Instability of Deformation

This chapter addresses the mechanisms by which instabilities can develop in rocks in the nominally ductile regime under conditions that the authors believe are relevant to Earth. We will not address brittle failure or frictional sliding processes in detail, but much of our discussion will be couched in terms of knowledge gained in studies of these processes. As a consequence, we will begin by discussing why brittle failure and frictional sliding cannot be the mechanism by which rocks become unstable at depth, despite the strong evidence that they are the underlying mechanism of earthquakes at shallow depths (e.g., Scholz 1990, 2002). Brittle shear failure in the normal sense is fundamentally a tensile process (tensile microcracks must first nucleate and self-organize via interaction of the stress concentrations at their tips). As a consequence, brittle failure and frictional sliding are strongly inhibited by pressure because work must be done against the pressure to open the Mode I cracks. The inhibition is so strong that the stress required to create a fault or initiate sliding on an existing fault becomes greater than the room-temperature flow stress of many rocks at pressures equivalent to only a few tens of kilometers in Earth. Increasing temperature has little effect on brittle processes, but in contrast, the ductile flow stress of rocks falls exponentially with temperature. Because both pressure and temperature increase with depth in Earth, earthquakes by unassisted brittle fracture mechanisms or frictional sliding can only occur at depths less than ∼30–50 km. Nevertheless, earthquakes occur to depths of almost 700 km in Earth and seismological evidence demonstrates unequivocally that they occur by displacement across a surface or narrow zone (i.e., they occur by faulting). This conundrum can be explained qualitatively by certain specific types of mineral reactions occurring under certain restricted conditions. The …
Transaction Data and Analysis: In Search of Concepts

The article focuses on two problems in the measurement of integration with transaction data. The first is the analysis procedure by which the transaction data are summarized. Different procedures affect the data in such different ways that they can actually lead to contradictory conclusions about the progress of integration. This article spells out some of the major differences in the models of analysis. The second problem is validity of transaction data as measures of integration. There are numerous different conceptualizations of integration, some centering on the development of central institutions, others on the existence of favorable attitudes among people, and still others on the existence of a highly co-operative relationship among states. It is not clear that transaction data are the most appropriate measure of any of these concepts.
SIM narrow- and wide-angle astrometric demonstration on the MAM testbed

The Space Interferometry Mission (SIM) requires fringe measurements to the level of picometers in order to produce astrometric data at the micro-arc-second level. To be more specific, it is necessary to measure both the position of the starlight central fringe and the change in the internal optical path of the interferometer to tens of picometers. The internal path is measured with a small heterodyne metrology beam, whereas the starlight fringe position is estimated with a CCD sampling a large concentric annular beam. One major challenge for SIM is to align the metrology beam with the starlight beam to keep the consistency between these two sensors at the system level while articulating the instrument optics over the field of regard. The Micro-Arcsecond Metrology testbed (MAM), developed at the Jet Propulsion Laboratory, features an optical interferometer with a white light source, all major optical components of a stellar interferometer and heterodyne metrology sensors. The setup is installed inside a large vacuum chamber in order to mitigate the atmospheric and thermal disturbances. Astrometric observations are simulated by articulating the optics over the 15 degrees field of regard to generate multiple artificial stars. Recent data show agreement between the metrology and starlight paths to 20pm in the narrow angle field and to 350pm in the full wide angle field of regard of SIM. This paper describes the MAM optical setup, the observation process, the current data and how the performance relates to SIM.
Work after retirement: intentions, realities and implications

The economic security of families in retirement is a function of levels of inflation and how well families can adjust their retirement incomes to meet inflation. One way of buffering the effects of inflation is to work part-time after retirement from one's main job. Studies of retired people, however, have indicated that levels of post-retirement work are low. This study of a near-retirement aged cohort offered a special early retirement incentive indicates that intentions to work after retirement from their main job are consistent with previous retired cohorts' work levels. On average, respondents anticipated working less than 3·5 h per week or less than 10 weeks per year. Major factors affecting the hours or weeks of work desired were age, life expectancy, perceived retirement income adequacy, marital status, health, sex, area of residence and education.
Guest Editorial: Special Section on Image and Video Databases

This PDF file contains the editorial “Guest Editorial: Special Section on Image and Video Databases” for JEI Vol. 7 Issue 02
“White Night”: Gentrification, Racial Exclusion, and Perceptions and Participation in the Arts

Art festivals are a feature of many urban districts undergoing gentrification; they help to catalyze change by drawing a set of consumers with particular cultural interests. This article examines w...
Modeling of a Two-Phase Electrochemical Reactor for the Fluorination of Organic Compounds. 2. Multiple Steady States

A three-cell, continuous-flow electrochemical reactor is numerically simulated, revealing multiple steady states in terms of production rate. The bipolar electrochemical reactor fluorinates organic compounds in liquid solution in parallel flow cells, accompanied by the generation of hydrogen gas. The mathematical model of two-phase flow, phase equilibrium, gas-phase molecular association, and thermal energy considerations by Drake et al. (Ind. Eng. Chem. Res. 2001, 40, 3109; J. Electrochem. Soc. 1998, 145, 1578) is extended to address interactive multiple cells. Necessary model extensions include intercell heat transfer through the bipolar electrodes, inlet flow-distributor connectivity, and serial current redistribution. Multiphase heat transfer, among these other cell-to-cell interactions, affects the occurrence of multiple states and profiles within differently operating parallel cells. A trifurcation point occurs at 17.3 V in the operating curve of total current versus applied potential. Here, this th...
Stratigraphic setting and mineralogy of the Arctic volcanogenic massive sulfide prospect, Ambler District, Alaska

The Arctic prospect is the largest (>36 million metric tons) volcanogenic massive sulfide deposit known within the Ambler district in northwestern Alaska. These deposits are hosted by the low-greenschist-grade, Devonian-Mississippian Ambler sequence (informal name) of bimodal, basaltic, and rhyolitic volcanic and volcaniclastic rocks, pelitic, graphitic, and calcareous metasediments. Detailed field mapping, core logging, petrography, X-ray diffractometry, and electron microprobe and whole-rock analyses of hydrothermally altered rocks were used to determine the emplacement history and setting of sulfide deposition. The Arctic prospect contains mineralization at three separate stratigraphic intervals. The largest and most economically important of these three intervals, termed the Main horizon, contains 90 to 95 percent of the known ore reserves. Main horizon minera]ization consists of one to possibly as many as 14 semimassive sulfide lenses within a well-developed, horizontally stratified sequence of alteration types, including pyritic (pyrite-phengite-calcite) and chloritic (chlorite-quartz) alteration, dolomite, phlogopite, albite, talc, and white mica. These alteration types together form a pervasively altered zone ( 3 which is asymmetric to the vent area for the ore fluids.The deposit is high in Cu and barite, has moderate amounts of Zn and Ag, and is low in pyrite, Fe, Pb, and Au. Ternary plots of Cu, Pb, and Zn abundances are very similar to those of massive sulfides formed at divergent plate boundaries, with total metal content at Arctic in the top 1 percent (Cu), 3 percent (Zn), and 4 percent (Pb and Ag) of volcanogenic massive sulfides worldwide. Strong lateral zonation of metals (Cu overlying the vent area, Zn intermediate, and Pb and Ag distal) parallels, but is offset from, an asymmetric distribution of alteration. Most sulfides were deposited not over the vent but on a relatively fiat area and in topographic channels between an elongate vent area pa]eohigh and a carbonaceous mudbearing basin to the northwest.No single volcanic unit can be genetically tied to mineralization. The onset of hydrothermal activity was apparently related to fault activity in the vent area and continued during emplacement of subsequent (postore) rhyolites. Mineralization at Arctic took place along a synvolcanic fault in a tectonically and volcanically active basin within a rifting continental margin, possibly related to an active oceanic rift. Jurassic(?) to Cretaceous, low-greenschist-grade (chlorite-muscovite subfacies) regional metamorphism was essentially isochemical on a macroscopic scale and preserved many primary features of the deposit and its host rocks.
SU‐FF‐T‐237: Exposure Rate Calculation: Effect Of Photon Divergence Near A Radioactive Source

The objective is to show that near a radioactive source the commonly used exposure rate equation has to be modified in order to take photon divergence into consideration. This is accomplished by showing the derivation of the standard equation in detail and then illustrating where photon divergence needs special consideration. The commonly used equation for calculating the exposure rate is Eq.1 and the modified equation Eq.2. The reason for the modification is that the irradiated volume per unit entrance area is larger at close proximities. This means that charge produced per unit volume per photon penetrating the entrance area is smaller at close proximities than at a distance. Since the exposure is defined as charge liberated per unit volume or unit mass of air this results in Eq.1 overestimating the exposure rate. This is of relevance (a deviation of 10% or more between expected and measured value) at distance smaller than 5 cm. At larger distances the difference between both equations becomes negligible. An experiment using a Tc‐99m point source and a calibrated exposure rate meter is performed to compare theoretical and experimental values and to show the difference between the predictions of the two equations. This comparison showed very good agreement of the measured values and the predicted values based on Eq.2 and an overestimation of the exposure rate calculated using Eq.1. This has also implications for the tabulation of Gamma factors ( ) and their units: (mR⋅cm∧2)/(mCi⋅hr) vs. (mR⋅cm∧3)/(mCi⋅hr). Eq. 1 : Ẋ [ mR hr ] = Γ Activity dis tan ce 2 Eq. 2 : Ẋ [ mR hr ] = Γ 3 Activity (dis tan ce + 1) 3 − dis tan ce 3 .
To sleep, perchance to integrate

One of the most intriguing and lasting proposals in psychological and neuroscience research is that sleep plays an important role in the consolidation of memories from a labile state into a permanent state. In recent years, there has been considerable research on this issue, and the findings have generated both supporters and skeptics locked in heated debate (1–3). A new study by Ellenbogen et al. (4) in this issue of PNAS contributes to this debate and may help us get past the superficial question of whether sleep plays a role by beginning to inform us on how sleep might contribute to information-processing that ultimately underlies memory consolidation.
Centrifugation of Mammalian Cells on Gradients: A New Rotor

A short-arm rotor increases separation of viable mammalian cells, from mixtures, by low-speed centrifugation; continuous Ficoll density gradients in tissue-culture media are used. We describe the theory and experimental demonstration of the superior separation achieved with this new rotor.
Ethnic groups' perception of physicians' attentiveness: Implications for health and obesity

Variables from the Health Tracking Household Survey 2007 were mapped to fit the "integrative model" of patient-doctor communication proposed by Ashton et al. (2003) to describe how communication patterns between patients and doctors influence patients' health outcomes. Patients' perceptions of their physician's attentiveness were examined to determine if perceived attentiveness mediated the relationship between physicians' recommendations (to diet and exercise) and health. Ethnic group differences related to these variables were explored. Overall, patient perception of physician attentiveness did significantly mediate the relationship between recommendations and patients' general health status. Hispanics and African Americans perceived their physicians as significantly less attentive to them, compared to Caucasians' perception of attentiveness. Across all ethnic groups, there was no evidence that doctors' recommendations to diet and exercise had an effect on patients' body mass index. The findings support previous research regarding the importance of physicians' communication skills and cultural sensitivity in promoting patient adherence to health recommendations.
Parent–adolescent concordance on perceived need for mental health services and its impact on service use

Abstract Mental health service underutilization among African American adolescents is well documented, yet not fully understood. Discordance between adolescents and their parents on perceived need for seeing a counselor for an emotional need or psychiatrist for psychiatric or medical services may help explain low service use among this population. This exploratory, prospective study examined the relationship between parent–adolescent concordance on perceived need for emotional counseling or psychiatric services and mental health service use. The relationships between gender and perceived service need and concordance and adolescent severity of depressive symptoms were also explored. Parent–adolescent dyads (n = 108) receiving community-based adolescent outpatient mental health services responded to interview questions concerning their perception of whether an emotional counselor and a psychiatrist were needed in the past six months. Findings revealed low parent–adolescent concordance on perceived need for an emotional counselor and a psychiatrist. A greater proportion of adolescents reported a need than parents. There was no association between gender and perceived need for an emotional counselor and a psychiatrist. Lower rates of parent–adolescent concordance were found among youth reporting elevated depressive symptoms compared to youth reporting normal range symptoms. Concordant dyads kept a higher number of appointments than discordant dyads. Implications for clinical social work practice and future research are discussed.
Predicted Folding of β‐Structure in Myelin Basic Protein

Predictions of myelin basic protein secondary structure have not previously considered a major role for beta-structure in the organization of the native molecule because optical rotatory dispersion and circular dichroism studies have provided little, if any, evidence for beta-structure, and because a polycationic protein is generally considered to resist folding into a compact structure. However, the Chou-Fasman, Lim, and Robson algorithms identify a total of five beta-strands in the amino acid sequence. Four of these hydrophobic amino acid sequences (37-45, 87-95, 110-118, and 150-158) could form a hairpin intermediate that initiates folding of a Greek-key-type beta-structure. A second fold on the more hydrophobic side, with the addition of a strand from the N-terminus (residues 13-21), would complete the five-stranded antiparallel beta-sheet. A unique strand alignment can be predicted by phasing the hydrophobic residues. The unusual triproline sequence of myelin basic protein (100-102) is enclosed in the 14-residue hairpin loop. If these prolines are in the trans conformation, models show that a reverse turn could occur at residues 102-105 (Pro-Ser-Gln-Gly). Algorithms do not agree on the prediction of alpha-helices, but each of the two large loops could accommodate an alpha-helix. Myelin basic protein is known to be phosphorylated in vivo on as many as five Ser/Thr residues. Phosphorylation might alter the dynamics of folding if the nascent polypeptide were phosphorylated in the cytoplasm. In particular, phosphorylation of Thr-99 could neutralize cationic residues Lys-106 and Arg-108 within the hairpin loop. In addition, the methylation of Arg-108 might stabilize the hairpin loop structure through hydrophobic interaction with the side chain of Pro-97. The cationic side chains of arginine and lysine residues located on the faces of the beta-sheet (Arg-43, Arg-114, Lys-13, Lys-92, Lys-153, and Lys-156) could provide sites for interaction with phospholipids and other anionic structures on the surface of the myelin lipid bilayer.
Neurologic disorders of gait.

Gait disorders are important because of their prevalence, particularly among the elderly, and the associated risk of falls and injury. Neural networks that organize locomotion and maintain balance are briefly reviewed. Gait disorders can be classified based on observational features or by etiology. Several common disorders are discussed in more detail. Recent progress includes use of botulinum toxin for spastic gait in cerebral palsy, neurosurgical treatment of Parkinson’s disease, and newer rehabilitation approaches to gait and balance training.
Analysis of the Corynebacterium diphtheriae DtxR Regulon: Identification of a Putative Siderophore Synthesis and Transport System That Is Similar to the Yersinia High-Pathogenicity Island-Encoded Yersiniabactin Synthesis and Uptake System

The diphtheria toxin repressor, DtxR, is a global iron-dependent regulatory protein in Corynebacterium diphtheriae that controls gene expression by binding to 19-bp operator sequences. To further define the DtxR regulon in C. diphtheriae, a DtxR repressor titration assay (DRTA) was developed and used to identify 10 previously unknown DtxR binding sites. Open reading frames downstream from seven of the newly identified DtxR binding sites are predicted to encode proteins associated with iron or heme transport. Electrophoretic mobility shift assays indicated that DtxR was able to bind to DNA fragments carrying the 19-bp operator regions, and transcriptional analysis of putative promoter elements adjacent to the binding site sequences revealed that most of these regions displayed iron- and DtxR-regulated activity. A putative siderophore biosynthesis and transport operon located downstream from one of the DtxR binding sites, designated sid, is similar to the yersiniabactin synthesis and uptake genes encoded on the Yersinia pestis high pathogenicity island. The siderophore biosynthetic genes in the sid operon contained a large deletion in the C. diphtheriae C7 strain, but the sid genes were unaffected in four clinical isolates that are representative of the dominant strains from the recent diphtheria epidemic in the former Soviet Union. Mutations in the siderophore biosynthetic genes in a clinical strain had no effect on siderophore synthesis or growth in low-iron conditions; however, a mutation in one of the putative transport proteins, cdtP, resulted in reduced growth in iron-depleted media, which suggests that this system may have a role in iron uptake. The findings from this study indicate that C. diphtheriae contains at least 18 DtxR binding sites and that DtxR may affect the expression of as many as 40 genes.
EXPERIMENTAL INFECTION WITH INFLUENZA A VIRUS IN MICE : THE INCREASE IN INTRAPULMONARY VIRUS AFTER INOCULATION AND THE INFLUENCE OF VARIOUS FACTORS THEREON.

Following intranasal inoculation of influenza A virus (strain PR8) there is a rapid increase of the virus in the lungs which with large doses reaches a maximum within 24 hours. With smaller doses, although the proportional increase is greater, the maximum concentration is not reached until 48 hours following inoculation. If a lethal dose is administered, the ultimate concentration of the virus in the lungs is the same, irrespective of the size of the dose. If a sublethal dose is given, the titer of the virus in the lungs does not achieve the titer reached in mice receiving a lethal dose. Within 48 hours following inoculation of a sublethal dose the lungs of a mouse may contain at least 76,000 M.L.D., yet the mouse survives. The intranasal instillation of sterile fluid (distilled water, varying concentrations of NaCl, broth, or 10 per cent normal serum) into a mouse sublethally infected produces a sharp rise in the virus content of the lung usually followed by death within 3 to 8 days. If, however, the instillate consists of 10 per cent immune serum, there is no rise in the virus titer, and no apparent harm results from the instillation. The implications of these phenomena are discussed and an hypothesis presented to explain their occurrence.
Validation of a survey instrument to assess home environments for physical activity and healthy eating in overweight children

Few measures exist to measure the overall home environment for its ability to support physical activity (PA) and healthy eating in overweight children. The purpose of this study was to develop and test the reliability and validity of such a measure. The Home Environment Survey (HES) was developed to reflect availability, accessibility, parental role modelling, and parental policies related to PA resources, fruits and vegetables (F&V), and sugar sweetened drinks and snacks (SS). Parents of overweight children (n = 219) completed the HES and concurrent behavioural assessments. Children completed the Block Kids survey and wore an accelerometer for one week. A subset of parents (n = 156) completed the HES a second time to determine test-retest reliability. Finally, 41 parent dyads living in the same home (n = 41) completed the survey to determine inter-rater reliability. Initial psychometric analyses were completed to trim items from the measure based on lack of variability in responses, moderate or higher item to scale correlation, or contribution to strong internal consistency. Inter-rater and test-retest reliability were completed using intraclass correlation coefficients. Validity was assessed using Pearson correlations between the HES scores and child and parent nutrition and PA. Eight items were removed and acceptable internal consistency was documented for all scales (α = .66–84) with the exception of the F&V accessibility. The F&V accessibility was reduced to a single item because the other two items did not meet reliability standards. Test-retest reliability was high (r > .75) for all scales. Inter-rater reliability varied across scales (r = .22–.89). PA accessibility, parent role modelling, and parental policies were all related significantly to child (r = .14–.21) and parent (r = .15–.31) PA. Similarly, availability of F&V and SS, parental role modelling, and parental policies were related to child (r = .14–36) and parent (r = .15–26) eating habits. The HES shows promise as a potentially valid and reliable assessment of the physical and social home environment related to a child's physical activity and eating habits.
Out-of-plane motion of a thrust sheet during along-strike propagation of a thrust ramp: a distinct-element approach

Abstract Using a 3D distinct-element mechanical modeling program, we examined the nature and magnitude of out-of-plane motion during along-strike propagation of a simple thrust ramp and attendant fault-related folding. Our numerical model was composed of about 83,000 spherical elastic particles that were bonded together to create an initial solid numerical rock mass, capable of macroscopic fracture and faulting in response to displacement loading. The algorithim is fully dynamic and as such allowed for the storage and sudden release of elastic strain energy in the form of seismic events. We induced progressive along-strike fault-growth and attendant non-cylindrical fold development by varying the along-strike friction within a seeded, planar zone of weakness within the aggregate, a zone that was to become the fault. The result was a well-developed, plunging ramp anticline that grew in amplitude and along-strike length as the macroscopic fault propagated from lower to higher friction regions. Lateral fault propagation was relatively rapid compared with shortening, with a ratio of thrust displacement-to-propagation length ( K ) of 6.5%. Incremental motion of the particles reflected episodic slip at both the laterally propagating fault-tip and along the existing fault. These episodes were characterized by local clusters of outward radiating velocity vectors that propagated at seismic velocities, marking the model equivalents of earthquakes. The finite displacement vectors in the hanging wall were approximately parallel to the far-field transport direction, with a strike-parallel component that ranged from one to two orders of magnitude less than the strike-perpendicular component. Furthermore, about two-thirds of the particles had strike-parallel motion in the direction of fault propagation and fold plunge. Because the far-field, shortening boundary conditions were uniformly perpendicular to fault strike, this component of motion in the plunge direction was apparently due to a topographically-induced, plunge-parallel shear stress. The along-strike motion involved slip on the main fault as well as transient strike slip on minor vertical, sometimes conjugate zones, apparently induced by the increased topographic load.