cssi/SciSciGPT-SciSciNet huggingface dataset:
Circular inhibition: a new concept in long-range interactions in the mammalian visual cortex

Horizontal long-range interactions are strongly involved in the generation of the receptive fields of visual cortical cells. Structurally imposed limitations of long-range interactions are demonstrated. In particular, it is shown that the cross-orientation inhibition scheme leads to inhomogeneous input for different cell populations which is experimentally not observed. This is not the case for circular inhibition, a new connection scheme proposed for long-range interaction. This is shown by computer simulation of the early visual system of the cat and by a simpler but analytically solvable model. The results are confirmed by applying the methods to the experimentally determined structure of the orientational hypercolumns in area 18 of the cat
The design of modern instrumentation for the measurement of gas expired from the lung.

A computational technique which leads to a manyfold reduction in the time required to obtain accurate measurements of gas volumes in pulmonary function studies is described. The function-of-function rule, used here to achieve an indirect analogue implementation of the integral of one variable with respect to another which is not time, is the basis for the design of new computer circuitry. Errors and other trade-offs inherent in this and earlier methods used to perform multiple breath nitrogen washout studies are compared.
Inhibitory effect of a hydrophilic alpha-tocopherol analogue, MDL 74,405, on generation of free radicals in stunned myocardium in dogs.

A previous study has demonstrated that the hydrophilic (α-tocopherol analogue, MDL 74, 405, attenuates postischemic myocardial dysfunction (“stunning”) in dogs. The present study was undertaken to determine directly whether the salutary effect of this drug on myocardial stunning results from inhibition of the generation of oxygen-derived free radicals. Open-chest dogs undergoing a 15-min coronary artery occlusion and 3 h of reperfusion received an intravenous infusion of either saline (controls, n = 7) or MDL 74, 405 (n = 6) starting 30 min before coronary occlusion and ending 60 min after reflow at a dose of 0.3 mg/kg/h. To measure free radical production, all dogs received an intravenous infusion of the spin trap α-phenyl N-tert-butyl nitrone (PBN) and local coronary venous plasma was analyzed by electron paramagnetic resonance (EPR). In control dogs, the myocardial production of PBN adducts exhibited an initial burst immediately after the onset of reflow and remained elevated until 10 min after reperfu...
Presence of direct thrombin inhibitors can affect the results and interpretation of lupus anticoagulant testing.

In vitro experiments were conducted to determine whether the direct thrombin inhibitors argatroban and lepirudin can interfere with the results of lupus anticoagulant (LA) testing. Concentration-response curves were generated to calculate the concentration of anticoagulant that prolongs the activated partial thromboplastin time (aPTT) to 75 seconds (2.5 times the baseline average). Corresponding concentrations of anticoagulant were added to plasma samples before running dilute Russell viper venom time (DRVVT) and LA-sensitive aPTT (PTT-LA) tests. Because the DRVVT test system contains an antiheparin agent, DRVVT results were not prolonged in the presence of heparin. With argatroban added to normal plasma samples, neither the DRVVT percent correction of ratio nor the DRVVT test/confirm ratio was elevated, but when added to LA-positive plasma, some false-negative results were observed. Lepirudin increased the DRVVT percent correction of ratio and the DRVVT test/confirm ratio into a range that could lead to false-positive identifications of LAs. In sharp contrast to the DRVVT test system, distinction between LA-positive and LAnegative plasma samples was maintained and possibly even enhanced in the platelet neutralization procedure correction phase of the PTT-LA test system. The antiphospholipid antibody syndrome is a clinical diagnosis characterized by vascular thrombosis or pregnancy morbidity observed in combination with laboratory evidence of antiphospholipid antibodies or lupus anticoagulants (LAs). 1-4 The term antiphospholipid antibody is a misnomer because the antibodies likely are directed toward phospholipid-binding proteins such as β2-glycoprotein I or prothrombin in combination with phospholipids such as cardiolipin,
Incidence of meningeal involvement by rhabdomyosarcoma of the head and neck in children. A report of the intergroup rhabdomyosarcoma study (IRS)

141 patients with embryonal rhabdomyosarcoma (RMS) of the head and neck are reviewed. 57/141 had lesions of para-meningeal sites. 20/57 (35%) developed evidence of direct meningeal extension. 18/20 (90%) died of this complication. Radiation portals and doses were limited in 42% and 32%, respectively. All patients had chemotherapy for 6 weeks prior to radiation. The significance of the adequacy of radiation factors and the timing of chemotherapy are reviewed. Recommendations for managing these patients include earlier use of radiation and increased coverage of adjacent meninges by radiation including total craniospinal axis radiation when brain meningeal involvement exists.
Sputter-deposited nanocrystalline Cr and CrN coatings on steels

Abstract Chromium and chromium-nitride coatings on steels have been deposited with a magnetron sputter-deposition system. The deposition power was 200 W pulsed DC with a frequency of 185 kHz and 96% deposition duty. The substrate temperature was maintained at 200°C. The sputtering gas was argon mixed with 0, 3, 5 or 7% nitrogen. Results show that the average deposition rate was 1.2 μm/h and was not affected by the nitrogen content in the sputtering gas. Using X-ray diffraction analysis, it was observed that the deposited Cr under pure argon condition, was nanocrystalline bcc chromium with a particle size in the range of 7–8 nm. With an increasing nitrogen content in the sputtering gas the amount of CrN increased. The measured microhardness of the chromium-coated steel increases with the increasing nitrogen content. With less than a 2-μm Cr coating, the steel hardness increases from 129 to 255 HV when the nitrogen content in the gas is 7%. The microhardness of Cr/CrN-coated steel prepared with sputter deposition is superior to that prepared with electroplating. The hardness of the coating layer calculated from these data is 1270 HV. Scratch tests were used to characterize coating adhesion. The critical load was determined to be the applied load under which an acoustic noise was found and cracks in the scratch track were first observed. The critical loads of deposited films with 0, 3, 5 and 7% N 2 in the gas, were 1.57, 5.68, 8.33 and 20.29 N, respectively.
Functional identification and characterization of sodium binding sites in Na symporters

Sodium cotransporters from several different gene families belong to the leucine transporter (LeuT) structural family. Although the identification of Na+ in binding sites is beyond the resolution of the structures, two Na+ binding sites (Na1 and Na2) have been proposed in LeuT. Na2 is conserved in the LeuT family but Na1 is not. A biophysical method has been used to measure sodium dissociation constants (Kd) of wild-type and mutant human sodium glucose cotransport (hSGLT1) proteins to identify the Na+ binding sites in hSGLT1. The Na1 site is formed by residues in the sugar binding pocket, and their mutation influences sodium binding to Na1 but not to Na2. For the canonical Na2 site formed by two –OH side chains, S392 and S393, and three backbone carbonyls, mutation of S392 to cysteine increased the sodium Kd by sixfold. This was accompanied by a dramatic reduction in the apparent sugar and phlorizin affinities. We suggest that mutation of S392 in the Na2 site produces a structural rearrangement of the sugar binding pocket to disrupt both the binding of the second Na+ and the binding of sugar. In contrast, the S393 mutations produce no significant changes in sodium, sugar, and phlorizin affinities. We conclude that the Na2 site is conserved in hSGLT1, the side chain of S392 and the backbone carbonyl of S393 are important in the first Na+ binding, and that Na+ binding to Na2 promotes binding to Na1 and also sugar binding.
Non-line-of-sight identification via phase difference statistics across two-antenna elements

This study proposes and investigates the performance of a new non-line-of-sight (NLOS) identification technique for multiple antenna systems that is based on the phase difference across two antenna elements. In order to avoid any confusion in the position location process, NLOS identification techniques should be implemented in the localisation systems. A phase wrapping selection algorithm is proposed to calculate the phase difference variance across two-antenna elements. A theoretical relationship is maintained between the phase difference variance and the Rician K -factor. The proposed K estimator requires an uncorrelated phase across antenna elements. The validity of this assumption is verified via channel modelling simulations. Then, a hypothesis test on the K -factor is formed to identify NLOS situations. The prior distributions of K -factor under line-of-sight (LOS) and NLOS conditions, and the K -factor threshold that are used to distinguish LOS and NLOS situation are derived. The impact of shadowing on the performance of the proposed NLOS identification method is studied. The performance of the proposed phase difference K estimator technique is compared with the envelope-based K estimator.
Dogs and horses with antibodies to outer-surface protein C as on-time sentinels for ticks infected with Borrelia burgdorferi in New York State in 2011.

Abstract Reported cases of Lyme disease (a chronic disease caused by infection with Borrelia burgdorferi ) in humans increased more than two-fold between 1992 and 2006 in the United States. Recently, the annual number of reported human Lyme disease cases stabilized (according to the Center for Disease Control and Prevention) but the geographic distribution seemed to increase. In New York (NY) State, USA, a spread from the original Lyme disease focus in southeastern parts of the state has occurred. We determined incidence risks of new companion animal infection in 2011 with B. burgdorferi by county in 451 dog and 2100 horse sera; the samples were non-randomly collected by referring veterinarians in NY State between June 15, 2011 and January 31, 2012 because of suspicion of infection with B. burgdorferi or during annual health checks. All samples were submitted to the New York State Animal Health Center; the samples were submitted from 50 out of 62 counties in the state. Incident infections were determined by measuring antibodies to outer surface protein C (OspC; a marker of early infection that is detectable in serum from 3 weeks to 5 months after infection). Incident infections with B. burgdorferi were detected in 23% (95% confidence interval (CI): 19, 27) of canine samples and in 8% (95%CI: 7, 10) of equine samples. In 21 counties, samples were submitted from only one species (i.e. only dogs or only horses) that indicated incident infection. Recognition of incidence infections in dogs and horses might serve as a sentinel for infected ticks in different NY State counties; detection of the OspC antigen can provide a sensitive, new tool to allow recognition of risk for possible human and animal infection with B. burgdorferi by geographic region. We recommend that both dogs and horses be part of such a passive surveillance system.
Pressure Sensitivity of a Thermal Shear Stress Sensor

This paper reports on the pressure sensitivity testing of MEMS thermal shear stress sensors. The MEMS sensor is a micromachined, vacuum-cavity insulated, thermal shear stress sensor for underwater applications. This paper is focused on the combined experimental and numerical study carried out to examine the effects of changing environmental pressure on the MEMS-based shear stress sensors. Four different sensors were tested experimentally and numerically. The silicon nitride diaphragms for each sensor are 4-μm thick. The length of each diaphragm is 210-μm while the widths are 210-μm, 150-μm, 100-μm, and 75-μm respectively. It is found that reducing the surface area size and increasing the thickness of the sensor diaphragms are effective in minimizing the pressure sensitivity.Copyright © 2003 by ASME
Biology and Potential Host Range of Pediobius ni (Hymenoptera: Eulophidae) as a Novel Resident Parasitoid of Light Brown Apple Moth (Lepidoptera: Tortricidae) in California

ABSTRACT Pediobius ni Peck (Hymenoptera: Eulophidae) is a eulophid parasitoid indigenous to North America that was found attacking the invasive light brown apple moth, Epiphyas postvittana (Walker) (Lepidoptera: Tortricidae), in California. We investigated host age suitability, fecundity, and temperature-dependent developmental time for P. ni as a parasitoid of E. postvittana. Parasitoid offspring survival was higher on E. postvittana presented as prepupa or young pupa ( 3d old), and P. ni would not attack mature E. postvittana larva. Parasitoid developmental time increased with advanced host age. At 24°C, P. ni parasitized 6.8 ± 0.7 hosts, and produced 119.5 ± 16.8 offspring during a 21.5 2± 3.0 d adult lifetime when provided food and host pupae. The developmental rate of P. ni was a positive linear relationship between 15–28°C, but it failed to develop at constant temperatures >29°C. The estimated lower developmental threshold is 13.0°C, and degree-day requirements (DD) are 27...
Inhibitory interactions between multimodal behavioural responses may influence the evolution of complex signals

Most animal displays make use of multiple sensory modalities (visual, acoustic and chemical signals) to convey similar information. Although multimodal displays may allow producers to use displays in a wider variety of social and physical contexts, it is difficult to explain their evolution because of the likely increased costs to senders and receivers. In this study, playback experiments in two contexts were used to study the behavioural responses to visual (headbob displays) and chemical (femoral pore secretions) signals in sagebrush lizards, Sceloporus graciosus. Lizards in the field tended to headbob in response to headbob displays and to engage in chemical exploratory behaviour when presented with chemical secretions. Territorial residents produced fewer headbob displays and head-turns in response to a combined signal produced by a robotic lizard than they did to either signal presented alone. This inhibition was confirmed in the laboratory, where presentation of a visual stimulus alone decreased chemical exploratory behaviour and presentation of a chemical stimulus alone decreased the number of headbob displays produced. The absolute cost of this interaction between sensory modalities may be low because the two behavioural responses are redundant, both allowing the receiver to acquire additional information, either by engaging a second lizard in a bout of interactive visual displays or by absorbing more of their scent. Thus, in sagebrush lizards, multiple signals may be evolutionarily maintained because behavioural responses to different sensory modalities are redundant and, hence, the cost of negative interactions between those responses is low.
Calcaneal Ultrasound Bone Densitometry Is Not a Useful Tool to Screen Patients With Inflammatory Bowel Disease at High Risk for Metabolic Bone Disease

Background: Up to 42% of patients with inflammatory bowel disease (IBD) have significant metabolic bone disease. The current method of screening for osteopenia or osteoporosis involves dual-energy x-ray absorptiometry (DXA). This is relatively costly and involves radiation exposure. What is needed is a safe, inexpensive, and quick screening tool to identify patients who would benefit from DXA testing. This would reduce the number of patients undergoing DXA testing unnecessarily. We tried to determine if calcaneal ultrasound bone densitometry is a useful tool in screening high-risk patients with IBD for metabolic bone disease. Methods: Patients with IBD who presented to the clinic between August 29, 2003 and December 22, 2003 were enrolled in this prospective study. All patients underwent calcaneal ultrasound bone densitometry screening using a GE Lunar Achilles Insight quantitative ultrasound densitometry machine (QUS). Patients who were at high risk for significant metabolic bone disease (i.e., significant previous prednisone use or a long history of severe IBD) or who had a T-score on QUS less than or equal to −0.7 had DXA testing performed. The DXA results and QUS results were compared. The radiologist was blinded to the results of QUS. Results: One hundred twenty-four patients with IBD were enrolled. Fifty (40%) were considered high risk for metabolic bone disease. This cohort was comprised of 29 men (58%), of which 21 (73%) had Crohn's disease (CD). Eighty percent of this high-risk group had CD, and in both groups, the majority had used corticosteroids. The overall risk of significant metabolic bone disease in this high-risk group was 62% (DXA ≤ −1.0). Heel density (T-score) correlated poorly with DXA (T-score) at either hip or spine at 0.40 even when 2 outlier patients (QUS = −2.9, DXA spine = 0.7, DXA hip = 0.8 and QUS = −3.6, DXA spine = −3, DXA hip = −4) were excluded. Likewise, no association in osteopenia or osteoporosis was seen between multiple variables. These included sex, disease type (ulcerative colitis or CD), smoking, and prior intestinal resection. The sensitivity of QUS to identify patients with significant metabolic bone disease was 74%, and specificity was 63%. A positive predictive value of 81% and negative predictive value of 53% were also less than ideal. The Altman-Bland analysis showed that the agreement between QUS and DXA was poor (−2.0, 2.1). Based on this analysis, QUS cannot replace DXA in the individual patient with IBD. Conclusions: Calcaneal ultrasound bone densitometry is not a useful tool to screen high-risk patients with IBD for metabolic bone disease.
Glycoalkaloids in solanaceae

Abstract The glycoalkaloid composition of eggplants, tomatoes, and potatoes is discussed with specific reference to history, occurrences, factors affecting levels, control of accumulation, analysis, and toxicity.
Use of digitonin-permeabilized cells in studies of steroid receptor subnuclear trafficking.

The application of a cell permeabilization technique to the analysis of nuclear import has led to many major breakthroughs in our understanding of this trafficking pathway. Digitonin permeabilization maintains the nucleus in a state competent for faithful, signal-dependent translocation through the nuclear pore complex. This system has also been used to probe the mechanism of hormone-regulated nuclear import through the use of glucocorticoid receptors (GR) as a model substrate. In this report we provide detailed descriptions of the digitonin-permeabilized cell system for use in studies of GR nuclear import. In addition, we present several novel applications that expand the utility of this system to probe for mechanisms of nuclear protein export and subnuclear trafficking.
Semi-empirical calculation of H atom interaction with a 12 atom iron cluster

Calculations have been made using the MINDO/SR procedure for Fe2, Fe12, FeH and Fe12H. The order of stability for H on Fe(100) symmetric sites is bridge > 4-fold > linear. Adsorption on edges is favored over center sites. The most stable plane site was a displaced bridge site. The H atom charges in the 4-fold, bridge and linear sites are + 0.16, + 0.03 and −0.17e respectively. The vibrational frequencies are 1150, 1340 and 1950 cm−1, respectively. No simple correlation of H binding energies with coordination numbers was found to exist. The calculations correlate the binding energy, vibrational frequency, work function change, photelectron spectra and LEED data into a consistent view.
On total variation diminishing schemes for pressure transients

A higher-order numerical procedure is applied to simulate typical transient phenomena in natural gas transportation. Reliable modeling and prediction of transients features in transmission pipelines are desirable for optimal control of gas deliverability, design and implementation of active controls, and modeling of operational behavior of network peripheral equipment (e.g., chokes, valves, compressors, etc.). As an alternative to the method of characteristics (MOC) that has been widely used for modeling these systems, higher-order total variation diminishing (TVD) methods are used to model some transient problems. This class of methods has the capability of capturing fine-scale phenomena, and they do provide a better resolution of frontal discontinuities. In this study, the TVD schemes are utilized in conjunction with upwind methods. Also, in order to ensure a stable time-stepping scheme over a wide range of Courant-Friedrich-Lewy (CFL) number, a special Runge-Kutta method is employed as the base solution algorithm to integrate the highly nonlinear, hyperbolic equations which govern the transportation of natural gas in pipelines. The overall procedure is stable, robust, and accurate when applied to solve practical problems with dynamic pressure waves.
Robotic radical prostatectomy: A technique to reduce pT2 positive margins

Abstract Objectives To describe a technique using the da Vinci robotic system that enhances one’s ability to visualize and dissect the apex and reduce surgical margins. An important outcome of radical prostatectomy is the reduction of iatrogenic positive margins in organ-confined prostate cancer. Technical considerations The clinical data of our first 140 consecutive robot-assisted radical prostatectomies were divided into two groups: group 1, cases 1 to 50; and group 2, cases 51 to 140. After reviewing the surgical margin data and appropriate video clips of our initial 50 patients, we altered our technique. Initially, we had used two sutures to control the dorsal venous complex (DVC), one proximally and distally. The prostate was freed, and, finally, the DVC and urethra were divided. However, a bundle of fat obscured the apex, leading to positive apical margins. We developed the following method. First, we removed all of the fat overlying the DVC and prostate. Second, we divided the puboprostatic ligaments and dissected the levator fibers to expose and increase the DVC length fully. Finally, we stapled and divided the DVC using a vascular stapler. Results The two groups were clinically comparable. Overall, the pathologic margin rate improved from 36% in group 1 to 16.7% in group 2. In group 1, 9 (27.3%) of 33 pT2 tumors had positive margins versus 3 (4.7%) of 64 pT2 tumors in group 2 ( P = 0.003). Conclusions The data demonstrate that this change in technique for robotic prostatectomy resulted in a more defined apical dissection and a statistically significant reduction in positive margins in patients with organ-confined disease.
Structure and propagation of triple flames in partially premixed hydrogen-air mixtures

Abstract The characteristics of triple flames in a hydrogen–air mixing layer are studied using direct numerical simulation with detailed chemistry. Triple flames are initiated by imposing a temperature ignition source in the center of a scalar mixing layer of nonuniform thickness, thereby forming a pair of freely propagating triple flames. Two different fuel streams are studied: pure hydrogen and hydrogen diluted with nitrogen. During the ignition stage, the initial ignition runaway is followed by a secondary peak as the ignition kernel transitions to a triple flame, consistent with previous observations. For both diluted and undiluted cases, the triple flame structure exhibits more similarity with a diffusion flame than with a premixed flame, such that the triple point, defined as the location of maximum heat release, is always in the proximity of the stoichiometric mixture fraction line. Similar to a previous study of methanol–air triple flames, the enhancement in the stabilization speed is attributed mainly to flow divergence, and its value is proportional to the square root of the density ratio across the flame. In the undiluted case, however, the asymmetric flame structure results in distinct locations where the stabilization speed and the displacement speed are maximum. The effect of unsteady strain rate is also studied by imposing a pair of vortices on the propagating triple flames. The negative strain rate results in the collapse of the premixed flame branches onto the diffusion flame, forming an edge flame structure. Excessive compressive strain and curvature at the triple flame tip leads to a negative displacement speed. A mixture fraction/temperature parameterization is shown to be useful in representing the structure of a triple flame subjected to unsteady strain rate.
Airborne lidar for fisheries applications

An airborne lidar using commercial, off-the-shelf components was developed by the National Oceanic and Atmospheric Administration for fisheries' surveys. We make several test flights of the system and develop several signal processing techniques to discriminate between the returns from fish and from small particles in the water. We use these techniques to produce several products of use to fisheries' biologists. Examples are presented of gray-scale images similar to those produced by acoustic echo sounders, of maps of spatial distributions of fish, and of vertical profiles of fish biomass. © 2001 Society of Photo-Optical Instrumentation Engineers. (DOI: 10.1117/1.1348000)
AIDS prevention in the United States: lessons from the first decade.

AIDS prevention programs in the United States have been relatively successful in providing accurate information on AIDS to a wide cross-section of the population, but less successful in helping people to change their risk behavior. The most significant changes have been reported in urban gay men, with lower levels of change in drug users, and the least change in young adult heterosexuals. Various obstacles to effective AIDS prevention interventions have been identified, including too great an emphasis on information; a reliance on one-way rather than interactive communication; a narrow categorical approach to AIDS; a failure to integrate prevention and treatment services; an unwillingness to acknowledge widespread distrust of government, scientists, and health officials; and a focus on individual behavior rather than the social and political factors that shape behavior. To address these obstacles, AIDS educators should identify and strengthen those cultural forces that support prevention while also challe...
3-D Velocity Imaging in the Shallow Subsurface using Multi-well, Multi-offset, VSP Data: A Case Study from the Lawrence Livermore National Laboratory Site

A vertical seismic profiling (VSP) method was developed to produce compressional (p-wave) velocity sections in a 3-D survey volume, down to a maximum depth of 57m. The VSP method consisted of a multilevel hydrophone tool deployed down several wells. Multiple offset surface shotpoints were recorded at multiple azimuths around each well head, using an impact source. The VSP data were processed and inverted to produce p-wave interval velocities. These velocity sections were then projected into a model of the survey volume, together with borehole log information and other geologic information, to produce a 3-D visualization which aided the location and interpretation of aquifer boundaries below the water table. The final image displayed several low velocity zones, and these were attributed to partially saturated pore spaces, possibly both natural, or pump induced by air suction. Low velocity layers appeared above several actively pumped aquifers, and it was concluded that the multi-offset, multi-azimuth, VSP ...
Exchange and Correlation in the Electron Gas

Recent theories of Singwi et al. for the dielectric response beyond the random-phase approximation are examined in the density-functional formalism. Their approximation and another from the perturbation expansion in the electron-electron interaction are used to calculate the correction to the local-density approximation of the exchange energy in atoms. The latter gives better results.
Cow as co-therapist: Utilization of farm animals as therapeutic aides with children in residential treatment

Using a mixed methodological approach, this exploratory study investigates the experiences of children who are placed in a residential treatment center that utilizes farm animals as one of its treatment approaches. The findings indicate that the children utilized the farm animals, like one would utilize the services of a therapist. Respondents indicated that they spoke to the animals, without fear that what they said would be repeated; that they visited the animals to feel better when they felt sad or angry; and that they learned about nurturing and caring for other living things. This article highlights a unique and novel approach to treatment that has not, as yet, been fully explored by the child welfare profession.
Glutamine synthetase is a genetic determinant of cell type-specific glutamine independence in breast epithelia.

Although significant variations in the metabolic profiles exist among different cells, little is understood in terms of genetic regulations of such cell type–specific metabolic phenotypes and nutrient requirements. While many cancer cells depend on exogenous glutamine for survival to justify the therapeutic targeting of glutamine metabolism, the mechanisms of glutamine dependence and likely response and resistance of such glutamine-targeting strategies among cancers are largely unknown. In this study, we have found a systematic variation in the glutamine dependence among breast tumor subtypes associated with mammary differentiation: basal- but not luminal-type breast cells are more glutamine-dependent and may be susceptible to glutamine-targeting therapeutics. Glutamine independence of luminal-type cells is associated mechanistically with lineage-specific expression of glutamine synthetase (GS). Luminal cells can also rescue basal cells in co-culture without glutamine, indicating a potential for glutamine symbiosis within breast ducts. The luminal-specific expression of GS is directly induced by GATA3 and represses glutaminase expression. Such distinct glutamine dependency and metabolic symbiosis is coupled with the acquisition of the GS and glutamine independence during the mammary differentiation program. Understanding the genetic circuitry governing distinct metabolic patterns is relevant to many symbiotic relationships among different cells and organisms. In addition, the ability of GS to predict patterns of glutamine metabolism and dependency among tumors is also crucial in the rational design and application of glutamine and other metabolic pathway targeted therapies.
Channels on Mars

By showing that parts of equatorial and mid-latitudinal Mars have a variety of channels and channel-like forms, Mariner 9 photographs provide a basis for speculations concerning surface processes, crustal events, climatological environment, and evolutionary history. Some large outflow channels display characteristics suggesting scour and plucking by torrential floods similar to the Spokane and Bonneville events of western United States, although such channels are probably not solely the product of flood action. Other channels with dendritic tributaries suggest runoff fed by seepage and headward growth and enlargement by sapping. Some Martian channels and channel-like forms were probably created or initiated by endogenic processes such as faulting, subsidence, volcanism, fracturing, and crustal extension; others may be due to wind or lava erosion, but the features and relationships of many channels are best accounted for by fluvial action. Reconciliation of fluvial erosion and the current hostile Martian environment may be possible if the channels are as old as 3 b.y. Such an age is suggested by recent re-evaluations of meteoroidal flux impacting Mars, Moon, and Earth and the chronology of lunar maria. A residual primitive atmosphere possibly congenial to running water on Mars may have permitted fluvial erosion 3 to 3.5 b.y. ago. Haphazard scattering of channels and the likelihood of seepage and sapping suggest that water was supplied to the Martian surface from the lithosphere, not the atmosphere.
Time-resolved kinetic monte-carlo simulation study on Si (111) etching

In this paper, we have extended the kinetic Monte Carlo simulation method to study the etching dynamics of Si (111) surfaces in NH 4 F on a time-resolved basis. We have examined the step-flow dynamics of Si (111) etching using various simulation window sizes for a variety of miscut angles and miscut orientations as well as other parameters which affect the formation of etch pits. The simulation results have been compared with published experimental data to derive an absolute time scale. Using the absolute time scale, we have further investigated the evolution of the initial surface morphology under two different miscut configurations. These results have been compared with a previously published experimental study.
Analog Storage of M-Mode Echocardiograph Signals Using Video Tape

Wide-band electrical signals representing the intensity of returning ultrasound echoes as a function of time may be stored and reproduced with excellent fidelity using standard videotape equipment, by adding appropriate synchronization pulses during intervals when the echo signal itself is quiescent. These pulses control the speed of the tape heads relative to the tape during recording, and the generation of a transverse sweep signal during playback. This technique permits repetitive generation of variously formatted displays of the same information, and computer editing of long echocardiograph records to produce abridged displays showing features chosen by appropriate selection algorithms. It may also be used to facilitate the digitization of echocardiograph signals for computer analysis.
An IgM-secreting cell line derived from the mouse plasmacytoma 104E expresses a different VH gene.

Abstract The BALB/c plasmacytoma 104E has been maintained in histocompatible mice for more than ten years. It secretes an IgM which binds α-1,3-dextran. The amino acid sequence of its λ light chain and μ heavy chain have been completely determined. Attempts to adapt 104E to continuous growth in culture led to the isolation of a ‘variant’ cell line (104-76), which produced IgM (μ,κ) and lacked dextran-binding specificity. We have purified the heavy chains from 104-76 and compared them with 104E μ. The 104-76 does secrete fully assembled IgM pentamers but the isolated μ chain has a different isoelectric focusing pattern from 104E μ. The cyanogen bromide fragments which orginate from the constant regions of 104E and 104-76 are the same size, but three of the four have a different charge, perhaps a result of the carbohydrate they bear. The cyanogen bromide fragments which originate all or in part from the variable region of 104-76 μ are completely different in both size and charge from the variable region fragments of 104E. These results indicate that 104E and 104-76 express completely different V h genes. Therefore, 104-76 is unlikely to be a simple mutational derivative of 104E. Alternative explanations for the origin of 104-76 are considered.
Use of the Wiener—Hermite expansion for nearly normal turbulence

The turbulence problem is formulated using the Wiener stochastic expansion. The expansion is useful for processes which are in some sense nearly normal, and can be used for non-linear non-Gaussian processes such as many turbulent fluid flows. Here we present the general formulation for statistically inhomogeneous and anistropic processes.The transfer term in the energy equation, or equivalently the third-order velocity correlation, forms a sensitive measure of the amount of non-Gaussianity present in real fluid flows. Experimental evidence shows that in many flows this component is small compared with the Gaussian part. It is shown that a homogeneous and isotropic flow which has but a small non-Gaussian part possesses a distribution at one point which is Gaussian to terms of second order. The experiments suggest that immediately behind a grid in a wind tunnel the flow is very nearly normal. The non-Gaussian part grows at a moderate rate, at least within the range of distance downstream (or decay time) available in the usual experiments. This growth is probably due to the relative increase in the amount of energy in the smallest eddies, which are non-normal.A necessary criterion for the validity of the zero-fourth-cumulant approximation is suggested: the transfer term in dimensionless form should be small. It is shown that calculations using the zero-fourth-cumulant approximation have given negative energy spectra when this condition is violated, probably for the reason that the process is no longer nearly Gaussian. However, even when this condition is fulfilled, it is shown that that approximation must be corrected.It is suggested that the present theory is valid for quite large times of decay if initial energy spectra are chosen which are not too far from the actual physical values for fluid in turbulent flow. Equations are given for the next-higher-order term in a nearly normal approximation. The expansion is also used in § 6 to describe turbulent mixing problems and is compared with the zero-fourth-cumulant approximation for these problems. Computational results are presented in § 7 and compared with experiments by Stewart and Townsend.
Potential Anti-Atherosclerotic Effects of Dipeptidyl Peptidase-4 Inhibitors in Type 2 Diabetes Mellitus

Cardiovascular disease (CVD) is the leading cause of mortality in patients with diabetes. Pharmacotherapy that can reduce hyperglycemia and also exhibit pleiotropic effects that can result in a reduction in cardiovascular disease will be a major advance. Recently, the dipeptidyl-peptidase-4 inhibitors were introduced as ant-hyperglycemic therapy. Studies from numerous groups have reported effects that could potentially result in a reduction in CVD. Some of the drugs in this class, especially vildagliptin and sitagliptin, have been shown to reduce postprandial hyperlipidemia following a fat load, improve endothelial function as evidenced by increased forearm blood flow, and also display anti-inflammatory effects. Their effects on platelet function, blood pressure, and oxidative stress are very preliminary and need to be confirmed. Finally, they have been shown to reduce subclinical atherosclerosis by reducing carotid intimal-medial thickness. However, the final arbiter with respect to a reduction in CVD will be the ongoing clinical trials.
The Relational Power of Education: The immeasurability of knowledge, value and meaning

Recognizing the challenge of adequate evaluation in higher education, this essay introduces some of the critical, alternative-seeking conversation about educational measurement. The thesis is that knowledge, value, and meaning emerge in the relational dynamics of education, thus requiring complex approaches to evaluation, utilizing relational criteria. The method of the essay is to analyse two educational case studies – a travel seminar and a classroom course – in dialogue with educational literature and a process-relational philosophy of education. Building from this analysis, the essay concludes with proposals for relational criteria of evaluation: relations with self, community and culture, difference, earth, and social structures.
The Aggressive and Territorial Behaviour of the Mantis Shrimp Gonodactylus Bredini Manning (Crustacea: Stomatopoda)

In the stomatopod Gonodactylus bredini when two individuals of the same sex encounter each other, they exhibit marked aggressive interaction. One animal usually becomes dominant over the other in approximately 10-20 minutes, and the frequency of aggressive acts declines steadily during the course of an hour. Dominance is influenced, although not necessarily determined, by size, stage in the reproductive cycle (females), stage in the moult cycle, and individual differences in level of aggressiveness. Aggressive behaviour involves a variety of fixed motor actions including spreading of the raptorial meri, antennular flicking, lunging with the meri spread, coiling of the body, and attacking and striking with the raptorial second maxillipeds. The meral expansion reveals conspicuous white spots on the inner surfaces of the raptorial meri and also silver streaks along the borders of the small first maxillipeds while the remaining maxillipeds are extended to form a rosette. This posture seems to serve as a threat. Because of structural modifications of the cuticle, especially on the dorsal surface of the telson, and of the frequent assumption of a coiled position during aggression, the strikes of attacking animals are seldom severely injurious. In nature G. bredini occupies cavities in rocks in shallow water from just below low tide line, and the aggressive behaviour is well suited to the defence of these cavities. The meral spread, for example, effectively fills the entrance and hence blocks encroachment by an intruder. The occupant may leave briefly to strike another animal or attack prey, but quickly returns to its home. The behaviour with respect to cavities thus seems to be territorial with the territory including the occupied rock plus a small area surrounding it. A resident animal undertakes several "housekeeping" activities including cleaning its chamber and closing the entrances at night with small bits of debris and reopening them the following morning. Only a particularly aggressive and dominant animal is capable of dislodging a cavity occupant, but eviction takes place rapidly when it does ocrur. Aggressive displays from outside alone seem insufficient to cause a def ender to leave a chamber ; takeover occurs when the attacker enters the cavity and drives the defender out.
EXPLORING THE KUIPER BELT : AN EXTENDED PLUTO MISSION

Abstract A robotic flyby mission to the planet Pluto is being planned for launch early in the next decade. The spacecraft will continue on out of the solar system in an almost radial direction traveling at about four AU per year and begin transiting the Kuiper Belt shortly after Pluto encounter. Recent discoveries and observations of Kuiper Belt objects have generated increased interest in the characteristics of these bodies. This paper examines the opportunities and requirements for extending the Pluto mission to include the search for, and encounters with, objects in the Kuiper Disk at 40+ AU. The trajectory and ΔV requirements will be presented. An automated, on-board sky survey will be proposed to inventory the Kuiper objects in the vicinity of the flight path and to identify which objects are candidates for altering the trajectory for a close flyby. A possible Kuiper object encounter science scenario will be described.
Colors of reflection nebulae. III - Ultraviolet scattering by small particles in reflection nebulae associated with 17, 20, and 23 Tauri

New surface brightness measurements in the reflection nebulae associated with the Pleiades stars 17, 20, and 23 Tau have been carried out with the IUE satellite. Each nebula was observed at two angular offsets south of the respective illuminating star. At the larger offsets (40, 40, and 60 arcsec respectively) each nebula exhibits a flux distribution which rises much more steeply with decreasing wavelengths than the corresponding stellar spectrum. At the smaller offsets (20 arcsec) the nebular spectra are more similar to those of the stars and fail to show the steep rise at wavelengths less than 2200 A. Independent observations of interstellar absorption lines as well as theoretical arguments by several previous authors lead to a model wherein the reflection nebulosity near the Pleiades stars is caused by a thin sheet of interstellar matter in front of the stars, at an approximate distance of a few x 10 to the -2nd pc. In the context of such a model the nebular spectra obtained near 17, 20, and 23 Tau can be understood only if the phase-function asymmetry of scattering declines with decreasing wavelengths throughout the spectral range. This result indicates that the role of scattering in the UV by particles in the 10 to the -6th cm size range appears more important than is generally recognized by current models.
Socioeconomic Disparities in Elementary School Practices and Children's Physical Activity during School

Abstract Purpose. To examine school socioeconomic status (SES) in relation to school physical activity-related practices and children's physical activity. Design. A cross-sectional design was used for this study. Setting. The study was set in 97 elementary schools (63% response rate) in two U.S. regions. Subjects. Of the children taking part in this study, 172 were aged 10.2 (standard deviation (SD) = 1.5) years; 51.7% were girls, and 69.2% were White non-Hispanic. Measures. School physical education (PE) teachers or principals responded to 15 yes/no questions on school physical activity-supportive practices. School SES (low, moderate, high) was derived from the percent of students eligible for free and reduced-price lunch. Children's moderate to vigorous physical activity (MVPA) during school was measured with accelerometers. Analysis. School level analyses involved linear and logistic regression; children's MVPA analyses used mixed effects regression. Results. Low-SES schools were less likely to have a ...
Geminate recombination of X-ray excited carriers in organic solids: Poly-n-vinylcarbazole

Abstract Experimental evidence is given to show that the yield of carriers bulk excited by X rays in films of poly-N-vinylcarbazole is dominated by geminate (initial) recombination of the electron-hole pairs. This mechanism has been verified for high pressure gases and some liquids, but this is the first unambiguous confirmation of geminate carrier recombination in a low mobility solid. The carrier yield versus applied field curve also allows an estimate of about 60A for the thermalization length of the hot electrons.
Morphine-Tolerant Mice Exhibit a Profound and Persistent Cardioprotective Phenotype

Background— Morphine and other opioids continue to be used as the major treatment for acute pain both before and after surgery. In this regard, much research has focused on the mechanisms of morphine tolerance and dependence in the central nervous system; however, few studies have examined the effect of morphine on peripheral organs, such as the heart, in morphine-tolerant animals. Here, we examine the effect of tolerance to the analgesic effect of morphine on ischemic tolerance in mice after prolonged morphine exposure and withdrawal. Methods and Results— Male C57/BL6 mice were implanted subcutaneously with either placebo or morphine pellets (25 or 75 mg). After prolonged exposure to and/or withdrawal from morphine or placebo, the hearts were excised and subjected to 25 minutes of ischemia and 45 minutes of reperfusion. Morphine-tolerant mice exhibited a markedly improved functional recovery compared with placebo and mice subjected to acute morphine. Lactate dehydrogenase release was also significantly reduced. The protection observed was equieffective 48 hours after withdrawal of pellet, whereas the onset of protection preceded analgesic tolerance. Conclusions— These data demonstrate that chronic exposure to morphine unexpectedly results in a profound and persistent cardioprotective phenotype. Received December 10, 2003; revision received January 9, 2004; accepted January 21, 2004.