cssi/SciSciGPT-SciSciNet huggingface dataset:
Covalent chemistry on distended proteins

Among the challenges in this postgenomic era are reliable predictions of protein conformation and conformational changes. Because the crystallographic database is relatively small and intrinsically limited to statically equilibrated conformations of proteins, experimental data sets are clearly needed for key dynamic states and their energetics. To begin filling this knowledge gap, several new methods have emerged over the last decade, especially at the single-molecule level, where distinct dynamical states are not blurred by bulk averaging. In the present context, Nobel Laureate Steven Chu has pointed out the flaw of such blind averaging by saying that the average human is a mixed sex type, which obviously describes no one individual's anatomical features.‡
USEFULNESS OF THE GROUP-COMPARISON METHOD TO DEMONSTRATE SEX DIFFERENCES IN SPATIAL ORIENTATION AND SPATIAL VISUALIZATION IN OLDER MEN AND WOMEN

This paper reports an analysis of sex differences in cognitive test scores covering the dimensions of spatial orientation and spatial visualization in groups of 6 older men and 6 women matched for speed of performance on a maze test and level of performance on a spatial relations task. Older men were more proficient solving spatial problems using the body as a referent, whereas there was no significant difference between the sexes in imagining spatial displacement. Matched comparisons appear a useful adjunct to population research to understand the type(s) of cognitive processes where differentia] performance by the sexes is observed.
Introduction to the special issue on ‘Frontiers in Gas Geochemistry’

Abstract The study of the geochemistry of gases pervades the Earth and Environmental Sciences. This is due in no small measure to the well-established thermodynamic properties of gases which allow their application to a variety of processes occurring over a wide spectrum of natural conditions. In this respect, both major and associated minor gases have been proven useful: indeed, the trace gases have been particularly important given their role as sensitive geochemical tracers. Examples where gas geochemistry places key constraints on geochemical processes include the degassing history of the solid Earth to form the atmosphere and oceans, the origin and migration characteristics of hydrocarbon deposits, the scale of climate variability, the P–T characteristics of geothermal reservoirs, and the dynamics of the earthquake cycle and volcanic activity, to name but a few. This volume continues this rich tradition with an eclectic selection of papers aimed at exploring and exploiting gas geochemistry over a myriad set of research themes.
Gray Matters: A Deployed Physician’s Perspective on Combat Medicine in Iraq

A female physician who was serving as a first-year medicine resident in Manhattan in September 2001 writes this paper. It details her experience of signing up for military service as a result of the September 11th attack on the United States. She lays out the surroundings, atmosphere, and reactions of those around her during the attack and details her own personal motivations for joining the military, her need to take control and help those in need heal while also trying to heal herself. Grateful, yet haunted by her experience, she provides an intimate glimpse into her time serving as a combat physician at a trauma hospital in Balad, Iraq during the 2007 military surge. A trained geriatrician and palliative care physician she recounts the stories of several patients that have forever shaped her life and explores the contradictions and ethical challenges she faced while caring for them ultimately struggling with the uncertainty of whether what she was truly doing was good for those she served or herself.
Reduction of Antiarrhythmic Drug Use in Patients Receiving Implantable Cardioverter Defibrillators

Widespread use of implantable cardiovertfir defibrillators (ICDs) for the treatment of ventricular tachycardia (VT) and ventricular fibrillation (VF) occurred in the late 1980s and early 1990s. Additionally, there has been increasing appreciation during this time for both the lack of efficacy and praarrhythmic activity of antiarrhythmic drugs to treat these cardiac arrhythmias. We evaluated the use of antiarrhythmic drugs from 1987 to 1991 (5-year period) at the time of ICD implantation in 25,450 patients. The use of all classes of antiarrhythmic agents decreased from 61% to 24% during this time period (P < 0.05), In addition, there was a significant reduction in antiarrhythmic agent use for each drug class (P < 0.05) with the exception of Class II agents (beta blockers). These changes in drug use occurred independent of any changes in age, sex, ejection fraction, prevalence of coronary artery disease, or type of ventricular arrhythmia (VT vs VF).
Risk Reduction Strategies Used by Leisure Travelers in the New-Buy Hotel Selection Purchase Situation

Services are perceived by consumers as possessing greater purchase risk than goods. This is especially true for new-buy situations. This research addresses risk reduction strategies used by leisure travelers when purchasing hotel services in the new-buy situation. To reduce purchase risk, travelers look for cues that will indicate the type of senlice they can anticipate. Specific cues that lowered purchase risk in the new-buy situation included the hotel's physical appearance, its reputation, and the anticipated behavior of the staff. Based on the results of this study. The authors recommend marketing and promotional strategies to attract the leisure traveler in the new-buy situation.
Bacteriological Examination of Shells and Contents of Eggs Laid by Turkeys Naturally or Artificially Infected with Salmonella typhimurium

Abstract EVIDENCE suggesting transmission of Salmonella typhimurium to turkey poults by means of infected eggs has been presented by Cherrington, Gildow, and Moore (1937) who recovered the organisms from ovaries of reacting turkeys and from “dead in shell” embryos. Lee, Holm and Murray (1936) reported the isolation of S. typhimurium from ovaries of artificially infected turkey hens. Hinshaw (1943) reported the recovery of the organisms from the ovary and oviduct of turkey hens. Pomeroy and Fenstermacher (1941) reported the isolation of parathyphoid organisms from 7 of 200 eggs that were incubated and failed to hatch, and they reported that S. typhimurium was isolated from the ovaries of 2 out of 9 reactors laying these eggs. These same workers (1941) showed that S. typhimurium passed through the unbroken shell and infected the embryos. Schalm (1937) showed that this same mode of infection can occur in chicken eggs. In the studies here presented . . .
Humanitarian intervention and post-conflict reconstruction in the post-Cold War era: a provisional balance-sheet

It is over twenty years since the ‘international community’ embarked on what seems to be an increasingly regular policy of intervening in the internal affairs of states on humanitarian grounds. A massive literature has developed that analyses the theoretical, political, legal, normative and strategic dimensions of humanitarian intervention. This article engages with that literature and attempts to draw a provisional balance sheet for this twenty-first-century activity by examining a number of key cases and analysing the motivations and drivers behind the decision to intervene as well as the practical consequences of the intervention itself. In the context of the recent crises in Libya, Syria and Mali, which are seemingly comparable situations but which have produced significantly different policy preferences on the part of the international community, the article concludes that there are few clear prescriptions as to when intervention is and is not appropriate or justified. The cases examined suggest that...
Effects of pH on inactivation of maize phosphoenolpyruvate carboxylase.

Abstract Maize leaf phosphoenolpyruvate carboxylase (PEPC) is inactivated by incubation at pH's above neutrality. Both the amount and the rapidity of inactivation increase as the pH rises. The presence of phosphoenolpyruvate (PEP), malate, glucose 6-phosphate and dithiothreitol in the incubation medium give protection to the enzyme. While the presence of PEP during incubation at pH 8 prevents inactivation, the level of PEP in the assay after incubation has no effect on the relative inactivation. When the enzyme is incubated at pH 7 with 5 m m malate (a treatment known to cause dimerization) subsequent assay at saturating levels of MgPEP completely restores activity while assay at 99% inhibition of the same sample, showing that high PEP concentration has reconverted the PEPC to the malate-resistant tetramer. Thus the protective effect of PEP against inactivation at high pH probably is not related to its effect on the aggregation state of the enzyme but rather is due to the presence of PEP at the active site. Protection of PEPC at pH 8 by EDTA and its inactivation by low concentrations of Cu2− indicates that the loss of activity at high pH probably is in a sense an artifact resulting from the binding to a deprotinated cysteine of heavy metal ions contaminating the enzyme preparation or present in reagents. This suggests that caution should be used in the interpretation of experiments involving PEPC activity at alkaline pH's.
Durability of latent heat storage tube-sheets

Abstract Compatibility and durability of phase change materials (PCM) and packaging laminate films were tested in this study. The objective was to identify viable component materials for heat storage tube-sheets. The tube-sheets are the essential part of a patented latent heat storage device. The unique feature of the device is its offset arrangement of mass-producible units. The results of cycling tests on two PCMs and one laminate are presented in this paper. After more than 1000 accelerated cycles of charging and discharging tests, the tubes maintained operable stability and showed no sign of deterioration. The PCMs displayed the same temperature-time pattern during the entire cycling test. The packaging laminate was compatible with the PCM's and capable of maintaining satisfactory strength.
Is renal ultrasound a reliable indicator of a nonobstructed duplication anomaly

Twelve kidneys which had a non-obstructed duplication anomaly on excretory urography were studied sonographically. Ten of the twelve kidneys had a single central renal sinus echo complex; only two kidneys had a split sinus complex typical of duplication. Sonography is not a reliable technique to identify a nonobstructed duplication anomaly.
Abstract A43: PPARδ promotes colonic inflammation and inflammation-associated tumorigenesis

Although epidemiologic and experimental evidence strongly indicates chronic inflammation as a risk factor for cancer, it remains unclear how chronic inflammation contributes carcinogenesis. Here we show that deletion of PPARδ diminishes colonic inflammation by reducing infiltration of immune cells via downregulation of pro-inflammatory chemokines and cytokine in a mouse model of colon inflammation. These chemokines are responsible for recruitment of leukocytes from the circulation to local inflammatory sites. Our results further reveal that COX-2 is a downstream target of PPARδ and COX-2-derived PGE2 stimulates macrophages to produce pro-inflammatory chemokines and cytokine. PGE2 is a crucial mediator of colorectal carcinogenesis. More importantly, loss of PPARδ attenuated colonic inflammation-associated adenoma growth in two mouse models of inflammation-associated colorectal cancer. Our results demonstrate that PPARδ promotes chronic colonic inflammation and colitis-associated tumorigenesis. Collectively, these findings indicate that PPARδ plays a pivotal role in connecting colonic inflammation to cancer progression and may represent a potential therapeutic target for prevention or treatment of colorectal cancer. Citation Information: Cancer Prev Res 2011;4(10 Suppl):A43.
Enhanced Thermoelectric Figure-of-merit at Room Temperature in Bulk Bi(Sb)Te(Se) With Grain Size of ∼100nm

Grain boundaries are known to be able to impede phonon transport in the material. In the thermoelectric application, this phenomenon could help improve the figure-of-merit (ZT) and enhance the thermal to electrical conversion. Bi2Te3 based alloys are renowned for their high ZT around room temperature but still need improvements, in both n- and p-type materials, for the resulting power generation devices to be more competitive. To implement high density of grain boundaries into the bulk materials, a bottom-up approach is employed in this work: consolidations of nanocrystalline powders into bulk disks. Nanocrystalline powders are developed by high energy cryogenic mechanical alloying that produces Bi(Sb)Te(Se) alloy powders with grain size in the range of 7 to 14 nm, which is about 25% finer compared to room temperature mechanical alloying. High density of grain boundaries are preserved from the powders to the bulk materials through optimized high pressure hot pressing. The consolidated bulk materials have been characterized by X-ray diffraction and transmission electron microscope for their composition and microstructure. They mainly consist of grains in the scale of 100 nm with some distributions of finer grains in both types of materials. Preliminary transport property measurements show that the thermal conductivity is significantly reduced at and around room temperature: about 0.65 W/m-K for the n-type BiTe(Se) and 0.85 W/m-K for the p-type Bi(Sb)Te, which are attributed to increased phonon scattering provided by the nanostructure and therefore enhanced ZT about 1.35 for the n-type and 1.21 for the p-type are observed. Detailed transport properties, such as the electrical resistivity, Seebeck coefficient and power factor as well as the resulting ZT as a function of temperature will be described.
Transonic Flow Quality Improvements in a Blowdown Wind Tunnel

The development and evaluation of a new type of flow conditioning system between the control valve and stilling chamber of the Vought Systems Division 4 X 4-ft transonic-supersonic wind tunnel are reported. The new system results in a series of normal shocks created by four perforated plates to dissipate total pressure differences between the reservoir and stilling chamber. Data are presented which demonstrate flow quality improvements obtained by using the new design, including a significant reduction in test section flow unsteadiness and elimination of flow angularity induced by the control valve at transonic Mach numbers. Design methods are developed which insure no loss in run time at transonic Mach numbers and minimum run time losses at higher supersonic Mach numbers.
Coherent effects of a weak neutral current

If there is a weak neutral current, then the elastic scattering process $\ensuremath{\nu}+A\ensuremath{\rightarrow}\ensuremath{\nu}+A$ should have a sharp coherent forward peak just as $e+A\ensuremath{\rightarrow}e+A$ does. Experiments to observe this peak can give important information on the isospin structure of the neutral current. The experiments are very difficult, although the estimated cross sections (about ${10}^{\ensuremath{-}38}$ ${\mathrm{cm}}^{2}$ on carbon) are favorable. The coherent cross sections (in contrast to incoherent) are almost energy-independent. Therefore, energies as low as 100 MeV may be suitable. Quasi-coherent nuclear excitation processes $\ensuremath{\nu}+A\ensuremath{\rightarrow}\ensuremath{\nu}+{A}^{*}$ provide possible tests of the conservation of the weak neutral current. Because of strong coherent effects at very low energies, the nuclear elastic scattering process may be important in inhibiting cooling by neutrino emission in stellar collapse and neutron stars.
Congenital subglottic hemangiomas: a treatment update.

Congenital subglottic hemangiomas are rare lesions associated with a significant degree of morbidity and mortality. Although various methods of treatment have been proposed, no one single modality has yet been shown to be uniformly effective in treating this life-threatening condition. Amongst the myriad of suggested treatments, the carbon dioxide laser, as originally proposed by Healy, et al.,1 appears to have the highest degree of success with the lowest incidence of complications. The purpose of this paper is to review a large experience at a single institution with the use of the carbon dioxide laser for treatment of congenital subglottic hemangiomas.
Baseline study of the concentration of molybdenum in bottom sediments of the major rivers in Colorado, U.S.A.

Abstract A study has been completed of the baseline concentrations of Mo in bottom sediments of the major rivers in Colorado. Three hundred and seventy-nine samples were taken from 14 rivers in the state. The geometric means for the concentration of Mo in the minus 80-mesh fraction of the sediment were found to vary from 1.2 to 14.0 ppm. The geometric mean for each river can be logically grouped according to the presence or absence of mineralization upstream in the drainage basin. This grouping results in three categories according to the extent and type of mineralization in the drainage basin. A grouping on the basis of mineralization accounts for 15% of the total variation in the concentration of Mo in the sediment, suggesting that Mo-rich sediment is transported downstream from mineralized areas and exerts a major influence on the baseline concentration. Multiple samples are required to characterize each river because the withinstream component of variance comprises 54% of the total variance. Bottom sediment (minus 80 mesh) is a sensitive indicator of Mo mineralization; values of molybdenum as low as 2 ppm were considered anomalous for several rivers. A precise analytical procedure permits detection of concentrations of Mo in sediment approximately 2 ppm below the detection limit of the usual potassium pyrosulfate-thiocyanate procedure.
X-ray Laue Diffraction from Protein Crystals

In conventional x-ray diffraction experiments on single crystals, essentially monochromatic x-rays are used. If polychromatic x-rays derived from a synchrotron radiation spectrum are used, they generate a Laue diffraction pattern. Laue patterns from single crystals of macromolecules can be obtained in less-than 1 second, and significant radiation damage does not occur over the course of an exposure. Integrated intensities are obtained without rotation of the crystal, and individual structure factors may be extracted for most reflections. The Laue technique thus offers advantages for the recording of diffraction patterns from short-lived structural intermediates; that is, for time-resolved crystallography.
What is life

If we encountered alien life, chances are we wouldn't recognise it – not even if it was here on Earth
SEASONAL PATTERNS OF RIVER CONNECTIVITY AND SALTWATER INTRUSION IN TIDAL FRESHWATER FORESTED WETLANDS

Hydrology can be difficult to interpret in tidal freshwater forested wetlands because of several influencing factors including river discharge, tidal stage, local precipitation, evapotranspiration, groundwater and prevailing winds. River discharge and tidal stage are considered the primary factors affecting these wetlands and both vary on a seasonal basis and have potential implications for wetland saltwater intrusion. We examined the hydrologic patterns of tidal freshwater swamps along the lower reach (20 km) of the Apalachicola River system in northwest Florida, USA. Water level recorders were installed in five wetlands along this reach and recorded ground and surface water levels at 15-min intervals from December 2006 to April 2009 (non-continuously). Seasonal trends related to flooding frequency and duration were compared to long term (2000–2008) records of creek and river salinities measured in the tidal freshwater forested zone. Tidal freshwater swamps tended to maintain a narrow water level range (often ±20 cm of the ground surface) except during high river flows (>680 cms or 24 000 cfs) when levels increased 1 to 2 m above ground and dampened tidal effects. All tidal forested wetlands had the highest mean water levels and most days tidally pulsed during the Jul–Oct season which coincided with peak river/creek salinities and low river-flows associated with drought conditions. We explored the implications for the timing of salt water intrusion in these swamps and potential changes related to sea level rise and water management in the Apalachicola River drainage basin. Copyright © 2011 John Wiley & Sons, Ltd.
Structural health monitoring of marine composite structural joints using embedded fiber Bragg grating strain sensors

This paper presents a method for the health monitoring of composite joints based on strain measurements using distributed embedded fiber Bragg grating (FBG) sensors. Secondary bonded woven E-glass/vinyl ester composite doubler plate joints were subjected to fatigue tension loading to induce stable crack propagation. A finite element (FE) model was developed to correlate experimental strain measurements prior to cyclic loading with the numerical predictions and to determine the sensitivity of the sensors to changes in longitudinal strain due to crack growth. Initial quasi-static tension tests demonstrated satisfactory correlation between the strains from the FBG sensors and FE predictions. The changes in longitudinal strain distribution during the fatigue tests were correlated with crack growth. A progressive shift in the strain distribution in the vicinity of the crack was observed. The experimental results demonstrated that a strain-based methodology can be utilized to detect crack propagation in this type of composite joints.
Cytochrome P450 Initiates Degradation of cis-Dichloroethene by Polaromonas sp. Strain JS666

Polaromonas sp. strain JS666 grows on cis-1,2-dichoroethene (cDCE) as the sole carbon and energy source under aerobic conditions, but the degradation mechanism and the enzymes involved are unknown. In this study, we established the complete pathway for cDCE degradation through heterologous gene expression, inhibition studies, enzyme assays, and analysis of intermediates. Several lines of evidence indicate that a cytochrome P450 monooxygenase catalyzes the initial step of cDCE degradation. Both the transient accumulation of dichloroacetaldehyde in cDCE-degrading cultures and dichloroacetaldehyde dehydrogenase activities in cell extracts of JS666 support a pathway for degradation of cDCE through dichloroacetaldehyde. The mechanism minimizes the formation of cDCE epoxide. The molecular phylogeny of the cytochrome P450 gene and the organization of neighboring genes suggest that the cDCE degradation pathway recently evolved in a progenitor capable of degrading 1,2-dichloroethane either by the recruitment of the cytochrome P450 monooxygenase gene from an alkane catabolic pathway or by selection for variants of the P450 in a preexisting 1,2-dichloroethane catabolic pathway. The results presented here add yet another role to the broad array of productive reactions catalyzed by cytochrome P450 enzymes.
Identification of resonance features within the rings of Saturn

The Voyager 2 UV spectrometer observed a stellar occultation by the rings of Saturn, which located ring features with an accuracy of 12 km. A high-resolution (3 km) optical depth atlas of the rings shows at least nine features, including four density wave patterns, identified with satellite resonances. Analysis of these density wave patterns yields the first surface mass densities for the A ring and, together with the optical depth atlas, a total ring mass of 6.4 x 10 to the -8th Saturn masses.
Changes in gastric sodium-iodide symporter (NIS) activity are associated with differences in thyroid gland sensitivity to perchlorate during metamorphosis.

Abstract We investigated stage-dependent changes in sensitivity of the thyroid gland to perchlorate during development of African clawed frog tadpoles ( Xenopus laevis ) in relation to non-thyroidal iodide transporting tissues. Perchlorate-induced increases in thyroid follicle cell size and colloid depletion were blunted when exposures began at Nieuwkoop–Faber (NF) stage 55 compared to when exposures began at NF stages 49 or 1–10. To determine if the development of other iodide transporting tissues may contribute to this difference we first examined which tissues expressed transcripts for the sodium dependent iodide symporter (NIS). RT-PCR analysis revealed that NIS was expressed in stomach and small intestine in addition to the thyroid gland of X. laevis tadpoles. NIS mRNA was not detected in lung, kidney, skin, gill, muscle, heart or liver. Perchlorate sensitive 125 I uptake was found in stomach, lung, kidney, gill, and small intestine but not muscle, liver, or heart. Perchlorate-sensitive 125 I uptake by stomach was 6–10 times greater than in any other non-thyroidal tissue in tadpoles. While NF stage 49 tadpoles exhibited perchlorate-sensitive uptake in stomach it was roughly 4-fold less than that observed in NF stage 55 tadpoles. Although abundance of NIS gene transcripts was greater in stomachs from NF stage 55 compared to NF stage 49 tadpoles this difference was not statistically significant. We conclude that gastric iodide uptake increases between NF stages 49 and 55, possibly due to post-translational changes in NIS glycosylation or trafficking within gastric mucosal cells. These developmental changes in gastric NIS gene expression may affect iodide availability to the thyroid gland.
Trapping of transiently formed quinone methide during enzymatic conversion of N-acetyldopamine to N-acetylnorepinephrine

We have demonstrated that quinone methide formation is an important aspect of insect physiology and proposed that enzymatically generated quinone methides react nonenzymatically with water or other nucleophiles to form Michael-1,6-addition products [(1988) Adv. Insect Physiol. 21, 179–231; (1989) J. Cell. Biochem. suppl. 13C, 58]. Using a purified o-quinone isomerase from the larval cuticle of Sacrophaga bullata and mushroom tyrosinase, we now demonstrate that transiently formed N-acetyldopamine quinone methide from N-acetyldopamine can be trapped by methanol to produce β-methoxy N-acetyldopamine. The methanol adduct thus formed was found to be a racemic mixture and can be resolved into the optical isomers on cyclodextrin chiral column. These results confirm our contention that enzymatically generated quinone methides are nonenzymatically and nonstereoselectively transformed to Michael-1,6-adducts by reaction with water or other nucleophiles.
Dilepton (e + e - ) production at Bevalac energies

Abstract The use of dilepton production in p-A and A-A collisions as a probe of nuclear matter under extreme conditions is described. Recent results from the DLS collaboration at the Bevalac are presented.
Stochastic Volatility in Interest Rates and Nonlinearity in Velocity

In this study it is shown that money velocity in a monetary equilibrium model is deterministically nonlinear when there are no exogenous uncertainties. Under some conditions, the asymptotic motion of money velocity is chaotic. When interest rates are stochastic and money and income growth are uncertain, the dynamics of money velocity are nonlinear and its coefficients are stochastic. We simulate the slope coefficient of the money velocity function and find that it is quite volatile. The Swamy and Tinsley (1980) random coefficient model is then estimated to compare the results with those from model simulation. It is found that the estimated stochastic slope coefficient has important similarity with the simulation results. The findings of this paper provide some useful information on the nature of the instability of money velocity.
Mechanisms of inflammatory pain: therapeutic implications.

Abstract:The study and treatment of clinical pain has historically identified particular pain syndromes and linked their etiology with disease factors. Missing in this approach is consideration of the mechanisms accounting for the pain that is experienced by the patient. The recent increase in our u
The association of chronic obstructive pulmonary disease, disability, engagement in social activities, and mortality among US adults aged 70 years or older, 1994–2006

Purpose To assess associations among chronic obstructive pulmonary disease (COPD), disability as measured by activities of daily living (ADL) and instrumental ADL (IADL), engagement in social activities, and death among elderly noninstitutionalized US residents.
Cathodoluminescence of Ce : La2Be2O5 single crystals

Abstract Ce 3+ : Y 3 Al 5 O 12 (Ce : YAG) is an important phosphor in high intensity CRT displays since it does not saturate at high electron beam power. The saturation power level is of the order of 1 W/cm 2 for most cathodoluminescent materials, and this limits the maximum surface brightness of a typical cathode ray tube. However, Ce 3+ : YAG has been found to be linear to at least 10 4 W/cm 2 . This performance has encouraged our examination of another cerium activated phosphor, lanthanum beryllate, Ce : La 2 Be 2 O 5 (Ce : BEL). A crystal of lanthanum beryllate activated with a cerium concentration of 410 18 atoms/cm 3 was grown by the Czochralski crystal growth technique. Wafers were prepared from the crystal and analyzed in both the as-grown state and after annealing in a flowing atmosphere of 10% by volume hydrogen in argon at 1150 °C for 4 h. Cathodoluminescent measurements revealed a broadband blue emission of 100 nm width centered at 480 nm, a blue-shifted analog of the Ce : YAG spectrum. A linear efficiency of 0.13 lm/W was found to a power loading of 8 W/cm 2 . Pulsed excitation of a Ce : BEL crystal by 375 nm radiation produced by frequency doubling of a 750 nm laser demonstrated a decay time of the fluorescence of the order of 50 ns. All these data show that Ce : La 2 Be 2 O 5 is an excellent candidate as a blue phosphor for high intensity CRT applications, particularly for high resolution projection displays using single crystal faceplates.
Generalized Holds, Ripple Attenuation, and Tracking Additional Outputs in Learning Control

Iterative discrete-time learning control can be very effective at improving the tracking performance of control systems. Three different limitations or potential dife culties of discrete-time learning control are addressed. 1 ) The number of output variables for which zero tracking error can be achieved is limited by the number of input variables. 2 ) Every variable for which zero tracking error is sought must be a measured variable. 3 ) Because the control action is digital, the intersample behavior may have undesirable error from ripple. The e rst issue is addressed by two approaches, either by seeking zero error for different output variables at alternating time steps or by skipping time steps. The latter corresponds to using a generalized hold device. To address the second issue, it isshown howthesetechniques can becombined with an observerwhen onewishesto haveimproved tracking ofnot only measured outputs but also unmeasured output variables. To improve ripple, one can ask for good tracking of theoutput,andinadditiongoodtrackingofitsderivativeorderivatives,anditisshownhowmethodsdevelopedhere can accomplish this. These generalizations are made for three different effective learning control laws: integral control-based learning with zero phase e ltering, which is particularly simple; a contraction mapping learning control, which is particularly robust; and a phase cancellation learning control, which is particularly effective at producing small e nal error levels in experiments.
A whole series of breakthroughs

The three men whose names are most closely linked with the invention of the transistor are Bardeen, Brattain and Shockley, and in 1956 they received the Nobel Prize for Physics for their work. Now, 25 years after their early remarkable experiments, the author looks back to those exciting days at Bell Telephone Laboratories.
Effects of pyrethroids on nicotinic acetylcholine receptor binding and function

Abstract The mechanism of interaction of two pyrethroids with the nicotinic acetylcholine (ACh) receptor was investigated by means of their effects on binding of radioligands to Torpedo electric organ receptor and its tracer ion flux, as well as by means of their effects on ACh sensitivity of denervated rat soleus muscle. Allethrin and fluvalinate had no effect on the equilibrium binding of 125 I-labeled α-bungarotoxin (α-BGT) to the ACh receptor, but both decreased its initial rate of binding in presence of carbamylcholine (carb). In absence of carb, only allethrin decreased the rate of 125 I-α-BGT binding slightly. Binding of [ 3 H]perhydrohistrionicotoxin (H 12 -HTX) to the channel sites of the ACh receptor was inhibited more by allethrin than by fluvalinate, but unlike H 12 -HTX, neither pyrethroid had much effect on receptor-activated 22 Na + influx into Torpedo microsacs, nor did fluvalinate reduce ACh sensitivity in denervated rat soleus muscle. Thus, it is suggested that the pyrethroids bind to a site that is different from the agonist or H 12 -HTX binding sites. Both fluvalinate and allethrin were potent in inhibiting receptor-activated 45 Ca 2+ uptake, and their effect increased with time. The RS fluvalinate isomer was more potent than the RR in inhibiting 45 CA 2+ uptake, in agreement with their relative toxicities to insects. Fluvalinate and allethrin (1 μ m ) increased the affinity of ACh receptors for carb at low concentrations and decreased it at high concentrations, suggesting that binding of pyrethroids affects agonist-induced conformational changes. The ACh sensitivity of denervated soleus muscle fibers was greatly depressed when the buffer was Na + free and contained 95 m m Ca 2+ , but fluvalinate significantly increased the ACh sensitivity. Thus, it is suggested that the pyrethroids bind to the nicotinic ACh receptor and interfere with receptor desensitization.
Particle Counting by Čerenkov Radiation

\ifmmode \check{C}\else \v{C}\fi{}erenkov radiation particle counters of a number of types are in satisfactory use in this laboratory for the counting of high energy mesons, electrons, and protons. The problems associated with \ifmmode \check{C}\else \v{C}\fi{}erenkov counting and some of the uses are discussed together with the design and performance of several types of counters. The uses include high energy electron counting with the exclusion of neutrons and protons, measurement of the velocity of mesons, and the detection of high energy neutrons in the presence of lower energy neutrons by the \ifmmode \check{C}\else \v{C}\fi{}erenkov threshold counting of recoil protons.
Nuclear medicine studies of aging--V. Uptake of 67Ga and 111In in the femoral vessels.

Fifty-nine males who had gallium-67-citrate or indium-111-oxine WBC scintigraphy (Ga/In) had the images reviewed to determine if increased activity was present in the femoral vessels and, if so, whether this was age related. The 59 subjects showed an age-associated increasing bilateral uptake (13% of 15 patients younger than 40 years, to 71% of the 7 who were older than 69 years). The combined unilateral and bilateral femoral uptake rose from 27% in those under age 40, to 86% in those over age 69. The group of 59 males included 30 (51%) who had bone scintigraphy with 99m Tc-MDP within 3 months of the Ga/In examination. These men showed the expected increase in femoral vessel 99m Tc-MDP uptake with age. Femoral vessel activity was more commonly observed with 99m Tc-MDP than with Ga/In. Thus both Ga/In and 99m Tc-MDP accumulate more frequently in the femoral vessels with advancing age. Ga/In displays this age-related phenomenon to a lesser extent than 99m Tc-MDP.
A Lexical-Functional approach to Japanese for the purpose of machine translation

Cette etude presente un ensemble de regles structurales de la phrase japonaise et une analyse du groupe verbal, dans le but d'en definir un traitement unique pour la traduction automatique
Marketing Meal Solutions

Abstract To regain sales lost to restaurants, many supermarkets developed meal solution programs. Inadequate marketing planning and execution contributed to the disappointing performance of many of these prepared food initiatives. Trends suggest that prepared food will continue to be a growth area and more restaurants are providing takeout and delivery services. By following sound marketing principles, supermarkets may be able to compete with both existing and emerging food-service meal solution concepts.
Luminescence Excitation Spectroscopy in Poly(p-Phenylene-Vinylene) Derivatives: Implications for a Semiconductor Band VS. Exciton Model in Conjugated Polymers

Abstract High-resolution luminescence excitation spectroscopy (site-selective flourescence) results are presented for two soluble derivatives of poly(p phenylene-vinylene): poly(2-methoxy-5-(2′-ethylhexyloxy)-p-phenylene vinylene) (MEH-PPV), and poly(2,5-bis(cholestanoxy)-p-phenylene vinylene) (BCHA-PPV). Measurements have been performed on both thin films of these polymers, and dilute blends in polyethylene oriented by tensile drawing. By examining the effects of oxygen exposure in cast films, and the energy- dependence of the luminescence anisotropy in the oriented blends, we provide evidence that the electronic states in the absorption tail arise from localized states in an amorphous semiconductor.
Subdural metastases from prostatic adenocarcinoma

Adenocarcinoma of the prostate commonly metastasizes to lymph nodes and bones, with occasional visceral deposits; lesions in the brain are rare. Although leptomeningeal carcinomatosis secondary to prostatic tumor has been reported, discrete cranial dural metastases from prostatic adenocarcinoma have not been described previously. The case of a patient having a unique adenocarcinoma of the prostate with bone, lymph node, and subdural metastatic lesions is presented.
Youth Developmental Assets and Perceived Life Satisfaction: Is There a Relationship?

This study explored associations between youth developmental assets (i.e., support by parents/other adults; accountability to adults; empowerment; school support; values regarding risk behaviors; quantity of other adult support; empathetic relationships) and adolescents’ perceptions of overall life satisfaction. Public high school students (N = 3,477) completed a self-report questionnaire. Analyses were conducted to examine relationships between developmental assets and perceived life satisfaction while controlling for socioeconomic status. Results indicated that significant (p ≤ .05) associations were established for perceived support by parents/other adults for all four race/gender groups, self and peer values regarding risk behavior for black females, quality of other adult support for black males and white females and life satisfaction for adolescents. Significant (p ≤ .05) associations were also established for perceived support by parents/other adults for White males and Black males, accountability to parents/other adults for White females, quality of other adult support for White males and Black females and for empathetic relationships for all four race/gender groups. Results suggest that perceived life satisfaction is related to youth developmental assets, although moderated by gender and race differences. Further research is necessary to identify the particular characteristics of youth and specific aspects of adolescent life satisfaction associated with youth developmental assets in order to develop gender appropriate and culturally sensitive health promotion programs.
Microstructural and electromagnetic characterization of La2−xSrxCuO4

Abstract A microstructural electromagnetic characterization of samples of La2xSrxCuO4 has been made. Evidence of percolative behaviour was seen in a.c. and d.c. magnetization measurements. Transport current densities were of the order of 1 A cm 2, about ten times smaller than the magnetization current density. The superconducting cluster size was estimated to be of the order of 1 1 μm. A detailed microchemical analysis was made over multiple regions of the sample, both within grains and at grain boundaries. No evidence was seen for the second phase, nor was there any large variation in chemical composition. Isolated dislocations and sub-grain boundaries were seen within the grains. We were not able to find any convincing microstructural evidence for percolative behaviour.
Design of streaming media server based on softswitch platform

According to the fact that Session Initiation Protocol (SIP) has been mainly used as a signaling protocol in the softswitch system, this paper discusses the implementation of a streaming media server based on SIP. Firstly, this paper presents the concept of streaming media and SIP. Secondly, it discusses the operating principle of a streaming media server and designs the architecture of it. Finally, it introduces a ReSIProcate, SIP protocol stack, and gives steps to implement a signaling module of the streaming media server using ReSIProcate.
Hippocampal long-term potentiation increases mitochondrial calcium pump activity in rat.

45Ca2+ pump activity was measured in hippocampal homogenates after the induction of long-term potentiation (LTP) of perforant path-dentate gyrus synapses in vivo. The mitochondrial poison, sodium azide, was used to separate mitochondrial from non-mitochondrial45Ca2+ uptake. High-frequency stimulation of the perforant path input produced a selectively increased mitochondrial uptake of calcium. This increased pump activity may permit granule cells to more effectively buffer higher intracellular calcium levels associated with LTP.
Magnetic field and temperature dependence of magnetic flux creep in c-axis-oriented YBa2Cu3O7 powder.

Creep of magnetic flux lines in a c-axis-oriented powder specimen of ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ was measured at temperatures of 5T50 K for fields in the range 0.1H4.0 T. Under most conditions, the magnetization M(T,H) was found, after sufficiently long times t, to decrease linearly with lnt. But at higher temperatures, this linearity was not observed up to t\ensuremath{\simeq}1.2\ifmmode\times\else\texttimes\fi{}${10}^{4}$ sec. An apparent flux-pinning potential ${U}_{0}^{\mathrm{*}}$ can be calculated using the relationship ${U}_{0}^{\mathrm{*}}$=kT{dM/[M d(lnt${)]\mathrm{}}}^{\mathrm{\ensuremath{-}}1}$. The value of ${U}_{0}^{\mathrm{*}}$ at 1.0 T was found to vary from \ensuremath{\sim}20 to \ensuremath{\sim}130 meV at 5 and 35 K, respectively, and also to increase with H. These results are not consistent with the expected temperature dependence of the true pinning potential ${U}_{p}$, and the difficulties in the use of the above relationship to determine ${U}_{p}$ for ${\mathrm{YBa}}_{2}$${\mathrm{Cu}}_{3}$${\mathrm{O}}_{7}$ are identified.
Nonlinear Dynamic Response of a Wind Turbine Rotor under Gravitational Loading

T nonlinear equations of motion for an isolated 3-deg flapping-lagging-feathering rotor blade are derived using Lagrange's equations for arbitrary large angular deflections. The aerodynamic forces and the tower interaction are not considered here. A consistent set of nonlinear equations is obtained by using nonlinear terms up to third order. The limit cycle analysis for forced oscillations and the principal parametric resonance of the flap-lag blade under a periodic gravity field are studied using the harmonic balance method. For a relatively small initial coning angle (about 9 deg), the nonlinearity becomes of the softening spring type, and large coupled responses are possible for rotational frequencies significantly lower than the lagging frequency.
Photometric calibration of brief flash sources: technical note.

From prior work is derived an equation for predicting errors incurred by the sole use of luminance values (0.05 of log factor of luminance increment above the calibrated value). A simple method was described for measuring the photometric result of a brief flash where peak candlepower is unknown.
Holographic photocurrent in photorefractive crystals

A transient photo-electric current was investigated in photorefractive crystals of Sr1-xBaxNb2O6 (SBN) and Bi12TiO20 (BTO) as a response to a step-like modulation of the light grating phase. Different dependencies of the photocurrent relaxation time on the grating period were observed for SBN and BTO crystals. It is explained theoretically taking into consideration kinetics of the photoexcitation of carriers, charge transfer and trapping. A number of important parameters characterizing the crystals are estimated.© (1996) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
An electrophoretic method for the detection of chymotrypsin and trypsin activity directly in whole blood

In biomedical research and clinical diagnostics, it is a major challenge to measure disease-related degradative enzyme activity directly in whole blood. Present techniques for assaying degradative enzyme activity require sample preparation, which makes the assays time-consuming and costly. This study now describes a simple and rapid electrophoretic method that allows detection of degradative enzyme activity directly in whole blood using charge-changing fluorescent peptide substrates. Charge-changing substrates eliminate the need for sample preparation by producing positively charged cleavage fragments that can be readily separated from the oppositely charged fluorescent substrate and blood components by electrophoresis. Two peptide substrates have been developed for pancreatic a-chymotrypsin and trypsin. For the first substrate, a detection limit of 3 ng for both a-chymotrypsin and trypsin was achieved in whole rat blood using a 4% agarose gel. This substrate had minimal cross-reactivity with the trypsin-like proteases thrombin, plasmin, and kallikrein. For the second substrate (trypsin-specific), a detection limit of about 10‐20 pg was achieved using thinner higher resolution 20 and 25% polyacrylamide gels. Thus, the new charge changing peptide substrates enable a simple electrophoretic assay format for the measurement of degradative enzyme activity, which is an important step toward the development of novel point-of-care diagnostics.
Illegitimate Civic Participation: Supporting Community Activists on the Ground

In this paper we examine the way Information and Communications Technologies (ICTs) support forms of community activism that operate outside formal political and institutional channels. We have done fieldwork with local housing justice activists in order to gain insight into the way ICTs play a role in complementing forms of civic engagement that challenge, rather than work with, institutional authority. We argue that ICTs are instrumental in supporting and shaping three alternate information practices' situating, codification, and scaffolding? that each serve the goals of direct democratic engagement. We also show how local activist communities engage in these three practices through their varied use of ICTs, including the ways they provide mechanisms for informal but politically significant? and legitimate? civic engagement.
Brain potentials associated with structural and functional visual matching

Abstract Ten subjects were presented with a series of slides composed of three figures each. Two of the figures were structurally matched (look alikes) while two were functionally (conceptually) matched. A tone burst preceded each slide by 100 msec. In mixed mode conditions, the frequency of the tone cued which type of match was to be performed on the following slide. In fixed mode conditions, the same type of match was made for each slide; the tones conveying only temporal information. Reaction time data indicated that functional matching was a more difficult task than structural matching. Spectral analysis of the EEG indicated that less alpha power was present for functional than structural matching. Mode of matching, however, had no effect on either the performance or spectral data. Two-event-related potential components were dissociated within the preparatory interval. The first component was sensitive to the mode of matching becoming larger parietally when the warning tone conveyed task relevant information. The second component was more pronounced centrally and asymmetric in its distribution over the two hemispheres for all experimental tasks.