cssi/SciSciGPT-SciSciNet huggingface dataset:
The influence of age of onset and acute anabolic steroid exposure on cognitive performance, impulsivity, and aggression in men.

A growing translational literature suggests that adolescent exposure to anabolic-androgenic steroids (AASs) leads to increased aggression and impulsivity. However, little is known about the cognitive effects of AASs among AAS users or the differences between adolescent- and adult-onset users. This study provides a test of the effects of acute naturalistic AAS use and age of onset (adolescent vs. adult) on measures of inhibitory control, planning and attention, and decision making. Seventy-one active adult male AAS users completed self-report measures of impulsivity and aggression, and a subsample (11 adolescent onset vs. 11 adult onset) matched on current age were administered 4 computerized tests from the Cambridge Neuropsychological Test Automated Battery (CANTAB) (Cambridge Cognition, 2002) and the Iowa Gambling Task (Stanton, Liening, & Schultheiss, 2011). Multiple regression analyses and a series of 2 (adolescent vs. adult) × 2 (on-cycle vs. off-cycle) analyses of variance (ANOVAs) were used to examine the differential effects of age of onset and acute drug use on cognition and behavior. Regression analyses revealed larger on-cycle effects for adolescent users than adult users. Subsample analyses indicated that on-cycle users performed less well on cognitive measures of inhibitory control and attention, but not on tests of planning or decision making. Adolescent onset was associated with greater impulsivity and more acute sensitivity to AAS effects on attention. These preliminary findings suggest the possibility that acute AAS use is associated with some differences in inhibitory control and impulsivity and to a lesser degree, aggression. These effects may be more potent for those initiating AAS use in adolescence. (PsycINFO Database Record (c) 2014 APA, all rights reserved). Language: en
Secondary reinforcement in infants

Abstract A spatial discrimination was successfully formed by 10-month-old infants during a single experimental session on the basis of secondary reinforcement. In the first task, S s received paired presentations of a tone and cereal for touching a target. After each reinforcement, 23 sec elapsed before another could be received and S heard a second tone during this period. In the second task, S s heard the food-paired tone ( T + ) each time they touched one of 2 new targets and heard the second tone ( T n ) each time they touched the other target. The number of responses producing T + was reliably greater than the number producing T n , thus demonstrating a genuine secondary reinforcement effect.
The use of dummy variables to compute predictions, prediction errors, and confidence intervals

Abstract This paper presents a method for computing predictions, prediction error variances, and confidence intervals, which can be implemented with any regression program. It demonstrates that a regression estimated for an augmented data set, obtained by (1) combining n sample points with r forecast points, and (2) including r dummy variables (each equalling one only for the corresponding forecast point), will yield r dummy variable coefficients and variances which equal the corresponding prediction errors and prediction error variances. Since most programs lack special routines to calculate these magnitudes, while manual computation is cumbersome, the proposed method is of considerable practical value.
Optical Detection of Brain Cell Activity Using Plasmonic Gold Nanoparticles

Metal nanoparticles are being actively explored for applications that use localized surface plasmon (LSP) resonance for optical sensing. Here we report an electrostatic field sensing technique which has been applied to detection of mammalian brain cell activity, by optically measuring the cellular potential induced shift in the SP resonance mode of an adjacent planar gold nanoparticle array. An experimental scheme was first devised which enables a quantitative calibration of the field-induced plasmon resonance modulation in air. Hippocampal (brain) neural cells were then grown onto the nanoparticle template and cellular level individual transient signals were detected optically when the chemically triggered neurons switched their potential. Experimental data are compared with calculations using the Drude model for the dielectric response of gold and the Stern model for the metal-electrolyte junction, with good agreement.
The Effect of Omitting a Limited Number of Subtests on the Full Scale Reliability of the WISC-R.

Changes in the full scale reliability of the WISC-R were computed at three age levels when each subtest was omitted by itself. Reliability was then determined when combinations of the two to five subtests which independently lowered the full scale reliability the most were omitted. The same procedure was followed with those subtests which independently had the smallest effect in lowering full scale reliability. The deletion of any one subtest had a negligible effect on reliability. Only when the combination of the five subtests having the greatest independent effect on full scale reliability was omitted did the reliability drop below.90. Cautions were rioted concerning the exclusion of sub-tests even when reliability remains acceptably high.
When the King Crosses the Line: Royal Deviance and Restitution in Levantine Ideologies:

Plagues and famines were recurring problems for people of the ancient Levant (eastern Mediterranean); and since these phenomena were perceived to be the actions of the gods, they required interpretation by authorized prophets and diviners. The seven passages discussed here all articulate a common behavioral pattern (with a king identified as the culpable deviant) and character-set with regard to these catastrophes. The motifs manifested are: breach of the sacred, divine punishment in the form of plague or famine, prophetic interpretation, restitution, and blood-sacrifice. The character-set is: the deity, the king/s, the prophet/s, and the suffering population. These Israelite, Hittite, and Greek narratives, while in the form of stories, prayer, and play, I identify as "Royal Deviance Narratives" (1 Sam 5:1-7:1; 2 Sam 21:1-14; 2 Sam 24:1-25; 1 Kgs 16:29-18:45; KUB xiv, 8; Iliad 1.1-475; and Oedipus Tyrannus), and I analyze them in terms of their motifs and their cultural scripts.
Organization of face and object recognition in modular neural network models

There is strong evidence that face processing in the brain is localized. The double dissociation between prosopagnosia, a face recognition deficit occurring after brain damage, and visual object agnosia, difficulty recognizing other kinds of complex objects, indicates that face and non-face object recognition may be served by partially independent neural mechanisms. In this paper, we use computational models to show how the face processing specialization apparently underlying prosopagnosia and visual object agnosia could be attributed to (1) a relatively simple competitive selection mechanism that, during development, devotes neural resources to the tasks they are best at performing, (2) the developing infant's need to perform subordinate classification (identification) of faces early on, and (3) the infant's low visual acuity at birth. Inspired by de Schonen, Mancini and Liegeois' arguments (1998) [de Schonen, S., Mancini, J., Liegeois, F. (1998). About functional cortical specialization: the development of face recognition. In: F. Simon & G. Butterworth, The development of sensory, motor, and cognitive capacities in early infancy (pp. 103-116). Hove, UK: Psychology Press] that factors like these could bias the visual system to develop a processing subsystem particularly useful for face recognition, and Jacobs and Kosslyn's experiments (1994) [Jacobs, R. A., & Kosslyn, S. M. (1994). Encoding shape and spatial relations-the role of receptive field size in coordination complementary representations. Cognitive Science, 18(3), 361-368] in the mixtures of experts (ME) modeling paradigm, we provide a preliminary computational demonstration of how this theory accounts for the double dissociation between face and object processing. We present two feed-forward computational models of visual processing. In both models, the selection mechanism is a gating network that mediates a competition between modules attempting to classify input stimuli. In Model I, when the modules are simple unbiased classifiers, the competition is sufficient to achieve enough of a specialization that damaging one module impairs the model's face recognition more than its object recognition, and damaging the other module impairs the model's object recognition more than its face recognition. However, the model is not completely satisfactory because it requires a search of parameter space. With Model II, we explore biases that lead to more consistent specialization. We bias the modules by providing one with low spatial frequency information and the other with high spatial frequency information. In this case, when the model's task is subordinate classification of faces and superordinate classification of objects, the low spatial frequency network shows an even stronger specialization for faces. No other combination of tasks and inputs shows this strong specialization. We take these results as support for the idea that something resembling a face processing "module" could arise as a natural consequence of the infant's developmental environment without being innately specified.
WE‐E‐201C‐03: Plate‐Specific Gain Map Correction for the Improvement of DQE in Computed Radiography

Purpose: To improve the NPS, and thus DQE, of CR images by correcting for pixel‐to‐pixel gain variations specific to each plate. Method and Materials: Ten high‐exposure, open field images were taken with an RQA5 spectrum, with a sixth generation CR plate suspended in air without a cassette. Image values were converted to exposure, the plates registered using fiducial dots on the plate, ten images averaged, and then high‐pass filtered to remove low frequency contributions from field inhomogeneity. A gain‐map was then produced by converting all pixel values in the average into fractions with mean of one. The resultant gain‐map of the plate was used to normalize subsequent single images to correct for pixel‐to‐pixel gain fluctuation. The normalized NPS (NNPS) for all images was calculated both with and without the gain‐map correction. Results: The NNPS with correction showed improvement over the non‐corrected case over the range of frequencies from 0.15 – 2.5 mm−1. At high exposure (40 mR), NNPS was 50–90% better with gain‐map correction than without. A small further improvement in NNPS was seen from careful registering of the gain‐map with subsequent images using small fiducial dots, because of slight misregistration during scanning. Conclusion:CR devices have not traditionally employed gain‐map corrections common with DR detectors because of the multiplicity of plates used with each reader. This study demonstrates that a simple gain‐map can be used to correct for the fixed‐pattern noise and thus improve the DQE of CR imaging. Such a method could easily be implemented by manufacturers because each plate has a unique bar code and the gain‐map could be stored for retrieval after plate reading. These experiments indicated that an improvement in NPS (and hence, DQE) is possible, depending on exposure level, over all frequencies with this technique.
A low power high noise immunity boost DC-DC converter using the differential difference amplifiers

A new boost converter using the differential difference amplifiers (DDAs) in the control loop is proposed. Compared with the traditional current mode boost converters, the circuitry of this controller is much simpler and consumes less power by eliminating the loop compensation, current sensing, and slope compensation circuits. A large duty ripple voltage generated by an Rr-Cr network is compared with the DDAs' outputs to get the duty cycles and changes the boost converter from a second order to a first order system. The large noise margin of the duty ripple voltage also gives this control excellent noise immunity performance.
Pulse-coupled neural network as a computer

Abstract. The biological neuronal model is an electrically polarized membrane capacitor with numerous ionicchannels for synaptic inputs and leakage currents. It is generally a complex system whose geometrical,electronic, and chemical substructures synergestically determine its temporal dynamics in response to itsinput distributions. The integrate-and-fire pulse generator resets a local internal voltage activity, which inturn interacts with the other voltage distributions in the dendrites. A recent closed-form solution to acompartmental neuronal model shows that it is a fully chaotic system with algorithmic properties that provide a new approach to object-oriented data processing.Introduction. The biological neuron is an electro-chemical system enclosed by an electrically polarized membrane thatmaintains a small potential difference between the interior and the surrounding sea of chemicals. The neuronis modelled as a simple capacitor. The membrane is not perfect, and so there are leakage currents. Thecellular chemistry works to compensate for these leaks and maintain the potential difference, but the manycomplex chemical interactions within and around the cell constantly generate leakage channels. Sometimesthe membrane fails altogether and a current of ions flows into the cell, and the electronic dynamics as thecell attempts to regain its stability (and its potential difference) causes a wave of voltage to flow over themembrane. The wave interacts with the delicate chemical balance around the cell. If another cell is nearby,it can be affected by these transient dynamics and develop a temporary leak in its membrane also. Worse,even when the cell manages to recover, it usually suffers some damage in the form of a change in itsleakage current capacity at the point of breakdown. The situation is complicated by multiple contactsamong adjacent cells, by the complex geometrical structure of the cells, and the all-prevading chemicalreactions and dynamical interactions.The biological neuronal model's task is to make sense of all this, which it does. However, there are furtherlevels of abstraction and generalization which interpert the biological system in terms of its functional
Interface catalytic effect: Cr at the Si(111)-Au interface

Synchrotron radiation photoemission studies of the effect of Cr interlayers on Si(111)-Au interface reaction show that Cr concentrations below 1\ifmmode\times\else\texttimes\fi{}${10}^{15}$ atoms/${\mathrm{cm}}^{2}$ retard Si-Au intermixing, concentrations between 1 and 7.5\ifmmode\times\else\texttimes\fi{}${10}^{15}$ atoms/${\mathrm{cm}}^{2}$ promote Si-Au intermixing, and concentrations in excess of 8\ifmmode\times\else\texttimes\fi{}${10}^{15}$ atoms/${\mathrm{cm}}^{2}$ sharply reduce intermixing. These variations are shown to depend on the three formation stages of the Si-Cr junction. Cr itself is shown only to be indirectly involved in the Si-Au reaction and Si is to be the only moving species.
Acute pain in the tip of the index finger

52-year-old female physician with stage I hypertension (avrage seated blood pressure, 146/98 mm Hg) developed suden-onset sharp throbbing pain in the tip of the left index finger ollowed by the development of splinter hemorrhages in the ail bed and cyanosis of the tuft of the same finger. A local ardiologist in the community administered amlodipine (5 mg aily), both to treat the hypertension and what he presumed as an atypical manifestation of Raynaud phenomenon. There as no history of collagen vascular disorder, fever, chills, ental work, skin lesions, or intravenous lines. Despite extenive medical history-taking, she could not recollect any trauma ccurring to her finger or hand before the development of the ain.
Review: In CKD, novel oral anticoagulants do not differ from vitamin K antagonists for efficacy or bleeding

Source Citation Harel Z, Sholzberg M, Shah PS, et al. Comparisons between novel oral anticoagulants and vitamin K antagonists in patients with CKD. J Am Soc Nephrol. 2014;25:431-42. 24385595
Detection of minimal residual disease in acute leukemia by flow cytometry.

Patients with acute leukemia in clinical remission may still have up to 10(10) residual malignant cells (the upper limit of detection by standard morphologic techniques). Sensitive techniques to detect minimal residual disease (MRD) may allow better estimates of the leukemia burden and help the selection of appropriate therapeutic strategies. Flow cytometry and polymerase chain reaction have emerged as the most promising methods for detecting submicrospopic levels of leukemia. Flowcytometric detection of MRD is based on the identification of immunophenotypic combinations expressed on leukemic cells but not on normal hematopoietic cells. It affords the detection of one leukemic cell among 10,000 normal bone marrow cells, and can be currently applied to at least two thirds of all patients with acute leukemia. Prospective studies in large series of patients have demonstrated a strong correlation between MRD levels during clinical remission and treatment outcome. Therefore, MRD assays can be reliably used to assess early response to treatment and predict relapse. In this review, we discuss methodologic aspects and clinical results of flowcytometric detection of MRD in patients with acute leukemia.
Age differences in response time to verbal and symbolic traffic signs

It is well established that verbal skills are maintained at a high level into old age while visuo-spatial skills begin to decline at an earlier age. it was hypothesized that the elderly would therefore respond more quickly to verbal traffic signs than to symbolic ones. In a test of this hypothesis, response times (RT's) to symbolic and verbal traffic signs were obtained from subjects in two age groups (19-29 and 65-77 years). While the elderly responded more slowly than the young subjects, they were an average of .2 seconds quicker in response to verbal traffic signs than symbolic ones. There were no differences in RT for symbolic and verbal signs for the young subjects. It is clear that the impact of traffic signs changes on the elderly deserves more attention than it is currently being given.
Age and origin of the Cortlandt Complex, New York: Implications from Sm-Nd data

Sm-Nd systematics for nine whole-rock samples of hornblende norites, pyroxenites and a lamprophyre from various parts of the Cortlandt Complex were analyzed. Six of these samples from the central and eastern parts of the complex give an isochron age of 430±34 (2σ) Ma with an ɛ Nd value of −2.9±0.5, and the other three samples from the western part, including the lamprophyre, define a similar age of 394±33 (2σ) Ma but with a distinctly different ɛ Nd value of −1.4±0.4. The two different initial 143Nd/144Nd ratios corresponding to these ɛ-values are interpreted to reflect continental crustal contamination of the lamprophyric parental liquid prior to final emplacement and crystal fractionation to produce the different rock types of the complex. The intrusion age of 430 Ma for the complex clearly post-dates the major metamorphic event of the Taconic orogeny. The Nd-isotopic data also suggest a relationship between the Cortlandt Complex and a belt of lamprophyric dike rocks to the west, known as the Beemerville trend, which cuts across the metamorphic trends of the Taconic (Ratcliffe 1981).
Application of open-ended rectangular waveguides for detecting surface cracks

Surface crack detection in metallic structures is an important issue in many environments (such as steel bridge members) and industries. A relatively new microwave method of detection using an open-ended rectangular waveguide has shown great practical promise. This method is quite versatile and may be applied to long, finite, filled, and covered cracks. Furthermore, crack dimensional analysis is also possible with this method. The measured and theoretical results of several exposed, filled, and covered cracks/slots are shown in this paper. Furthermore, a new theoretical approach to model the interaction of the waves incident at the waveguide aperture and a metal surface with a crack are very briefly mentioned as well. The results show the utility of this method for detecting filled and covered cracks as well as cracks separated from the waveguide aperture by a slight amount of airgap (i.e. noncontact approach).© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Insulin-stimulated GLUT4 Translocation in Adipocytes Is Dependent upon Cortical Actin Remodeling ,

Rhodamine-labeled phalloidin staining of morphologically differentiated 3T3L1 adipocytes demonstrated that F-actin predominantly exists juxtaposed to and lining the inner face of the plasma membrane (cortical actin) with a smaller amount of stress fiber and/or ruffling actin confined to the cell bottom in contact with the substratum. The extent of cortical actin disruption with various doses of either latrunculin B or Clostridium difficile toxin B (a Rho family small GTP-binding protein toxin) directly correlated with the inhibition of insulin-stimulated glucose uptake and GLUT4 translocation. The dissolution of the cortical actin network had no significant effect on proximal insulin receptor signaling events including insulin receptor autophosphorylation, tyrosine phosphorylation of insulin receptor substrate and Cbl, or serine/threonine phosphorylation of Akt. Surprisingly, however, stabilization of F-actin with jasplakinolide also resulted in a dose-dependent inhibition of insulin-stimulated glucose uptake and GLUT4 translocation. In vivo time-lapse confocal fluorescent microscopy of actin-yellow fluorescent protein demonstrated that insulin stimulation initially results in cortical actin remodeling followed by an increase in polymerized actin in the peri-nuclear region. Importantly, the insulin stimulation of cortical actin rearrangements was completely blocked by treatment of the cells with latrunculin B, C. difficile toxin B, and jasplakinolide. Furthermore, expression of the dominant-interfering TC10/T31N mutant completely disrupted cortical actin and prevents any insulin-stimulated actin remodeling. Together, these data demonstrate that cortical actin, but not stress fibers, lamellipodia, or filopodia, plays an important regulatory role in insulin-stimulated GLUT4 translocation. In addition, cortical F-actin does not function in a static manner (e.g. barrier or scaffold), but insulin-stimulated dynamic cortical actin remodeling is necessary for the GLUT4 translocation process.
A diurnal and seasonal study of the resting behaviour of Glossina pallidipes Aust.

In conjunction with an investigation of the diurnal and seasonal feeding behaviour of Glossina pallidipes Aust. in dense riverine vegetation in the Zambezi Valley, Southern Rhodesia, gorged flies caught on a stationary ox were marked and released and their subsequent resting places recorded. Fallen logs, a rot hole, boles and branches were found to be utilised in the late hot dry season (November), but in the rainy season (February), the cool season (May) and the early dry season (August), flies were found almost entirely on branches. Of the total resting flies observed, 89 per cent, were at heights of 0 to 9 ft., but whereas in November 49 per cent, of resting flies were at heights between 0 and 3 ft., only 10 to 19 per cent, rested at this level in the other seasons. The choice of more deeply shaded resting sites in November is thought to be due to a reversal, at temperatures over 35°C., of a normally positive reaction to light. The resting behaviour did not appear to differ greatly between sexes, although females do not move so readily as do males on to sites other than branches.In November, a diurnal pattern of resting behaviour was noted. A branch type of site was preferred in the early morning, but a shift to the rot hole and boles was evident during the middle of the day, followed by a return to branches in the evening; there was evidence that flies rested in yet another type of site at night. In May, searches from 1930 to 2100 hr. for flies marked with reflecting paint revealed some on leaves and small twigs.
Experimental comparison of the dynamic performance for steel, aluminum and glass-fiber-reinforced-polymer light poles

This study is conceived as the second part of an experimental analysis and focused on the performance of tapered highway light poles under dynamic excitation. The original motivation coincides with a forensic investigation for the definition of the most plausible collapse cause for aluminum-alloy highway light poles during a wind and winter storm. The comparison of the performances is based on frequency and damping ratios corresponding to first- and second-mode vibration. Experimental testing is employed to derive the dynamic characteristics of the units; moreover, the behavior of a damping device, previously proposed for mitigation of vulnerable units, is analyzed. Previous results, derived for a limited set of cases, are extended in this study to other configurations, including different materials and geometry. Discussion on the derivation of frequency and damping in the presence of closely spaced modes, typical of these systems, is provided. In particular, the effectiveness of several methods for the identification of such quantities is carefully compared.
Brain space for a learned task

Forty-six adult male and female canaries were sacrificed, their brains were weighed and the volume of several brain nuclei reconstructed from the cresyl violet-stained material. Two forebrain vocal control nuclei, hyperstriatum ventrale, pars caudale (HVc) and nucleus robustus archistriatalis (RA), were approximately 4 and 3 times larger, respectively, in males than in females, confirming previous findings. There was no consistent right-left asymmetry in the volume of these nuclei in males and females. Twenty-five male birds in this study had their song repertoire recorded during the peak of the singing season. They were sacrificed 3 to 4 months later. The size of the song repertoire, measured as number of different syllable types, showed a positive and significant correlation with the size of HVc and RA. There was no significant correlation between size of the syllable repertoire and age, brain weight or the volume of two brain nuclei not involved in song control. This is the first time that the amount of brain allotted to a specific learned skill has been shown to correlate positively with the amount of that skill that is learned. Interestingly, too, there was a positive and significant correlation between testis weight at the end of the breeding season and the volume of RA at that time, suggesting a hormone-mediated seasonal modulation of part of the brain space occupied by song control pathways. This material seems well suited for studying the relation between space and learning, and the manner in which this relation is influenced by gonadal hormones.
Assistive embedded technologies

Embedded computing technologies are not only an integral part of traditional safety- critical applications such as jet engine and automotive brake control, they are also being used to improve people's quality of life. Trinetra integrates embedded devices to let blind users enjoy cost-effective, independent shopping. The day-to-day needs of a typical blind user greatly influenced our design and evaluation of the Trinetra system. From the beginning, the user of our system also proved instrumental in helping design and tests the system
Stimulatory effect of vitamins and glutamine on the differentiation of germ cells in rat testes organ culture grown in chemically defined media

Abstract Testes from 4-day-old rats were grown as organ cultures in completely chemically defined media. Spermatogenesis was initiated and progressed to pachytene stage of the meiotic division in complete absence of pituitary gonadotropins. In the presence of combined vitamins A, E and C, or 4 mM-concentration of glutamine, gonocytes differentiated into pachytene spermatocytes at a slightly slower rate than in vivo. Qualitative and quantitative differences were observed between cultures nourished by various media. The possible role of glutamine as an essential factor in differentiation is discussed.
A surface phospholipase is involved in the migration of plasmodium sporozoites through cells.

Plasmodium sporozoites, injected by mosquitoes into the skin of the host, traverse cells during their migration to hepatocytes where they continue their life cycle. The mechanisms used by the parasite to rupture the plasma membrane of the host cells are not known. Here we report the presence of a phospholipase on the surface of Plasmodium berghei sporozoites (P. berghei phospholipase; Pb PL) and demonstrate that it is involved in the establishment of a malaria infection in vivo. Pb PL is highly conserved among the Plasmodium species. The protein is about 750 amino acids, with a predicted signal sequence and a carboxyl terminus that is 32% identical to the vertebrate lecithin:cholesterol acyltransferase, a secreted phospholipase. Pb PL contains a motif characteristic of lipases and a catalytic triad of a serine, aspartate, and histidine that is found in several phospholipases. We have verified its lipase and membrane lytic activity in vitro, using recombinant baculovirus-expressed protein. To study its role in vivo, we have disrupted the P. berghei PL open reading frame and generated mutants in its active site. During an infection through mosquito bite, the infectivity of the knock-out parasites in the liver is decreased by ∼90%. The prepatent period of the resulting blood infection is 1 day longer as compared with wild type. Further, the mutant sporozoites are impaired in their ability to cross epithelial cell layers. Thus, the Pb PL functions as a lipase to damage cell membranes and facilitates sporozoite passage through cells during their migration from the skin to the bloodstream.
Remnants of a fossil alluvial fan landscape of Miocene age in the Atacama Desert of northern Chile using cosmogenic nuclide exposure age dating

We have used cosmogenic nuclides to estimate limits on the surface exposure durations and erosion rates of alluvial fans and bedrock surfaces in the Atacama Desert in Chile. The oldest landforms we studied are extensive alluvial fans referred to as “Atacama gravels”. With the exception of samples collected in Antarctica, the cobbles collected on these alluvial surfaces have the lowest erosion rates of any samples, as determined by cosmogenic nuclides, analyzed to date. The oldest cobble has a model surface exposure age of 9 Myr, based on combined measurements of cosmogenic 10Be, 26Al, and 21Ne concentrations. Cobbles from the alluvial fans are eroding slower than the surrounding steep mountainous bedrock surfaces. Maximum erosion rates for cobbles on alluvial surfaces are uniformly < 0.1 m/Myr. The survival of these gravels, specifically, and more generally, the stability of landform features in this geographic area is made possible by the attainment of hyperarid conditions in the Atacama Desert resulting from global climatic cooling about 15 Myr ago combined with the rain shadow effect caused by uplift of the Central Andes. The landform features observed presently in the Atacama Desert are remarkably stable and, despite the inevitable erosion that is detectable using cosmogenic nuclides, undoubtedly bear considerable resemblance to conditions as they existed in the Miocene. Over geologic time, the Atacama landscape is evolving in such a manner as to erode the higher bedrock ridges relative to the more stable, but stratigraphically lower depositional surfaces through which clastic detritus now travels occasionally along the floors of incised drainage systems leaving the older permeable alluvial fan surfaces largely intact as widespread remnants of a Miocene fossil landscape.
Selecting Bacterial Mutants by the Penicillin Method

Certain improvements are described in the use of penicillin for isolating auxotrophic mutants of bacteria. By obtaining exponential growth before the penicillin is added, and by minimizing the duration of the treatment, cross-feeding is decreased and much denser populations can be screened. These modifications have made it possible to obtain, with regularity, mutants of Escherichia coli blocked in a desired step in arginine biosynthesis.
Variations in phosphoryl substituents in extracellular peptidophosphogalactomannans fromPenicillium charlesii G. Smith

Abstract Soluble extracellular peptidophosphogalactomannans released by Penicillium charlesii were obtained from filtrates of cultures grown in 48 different defined liquid media containing varied sources and levels of carbon, nitrogen, sulfur, and phosphorus nutrilites. Glycopeptides were separated into four well-resolved fractions by chromatography on DEAE-cellulose-borate. Gross chemical analyses of the four glycopeptide fractions revealed modest, though consistent, differences in peptidyl, galactosyl, mannosyl, and phosphate contents and in amino acyl compositions. Carbon-13 nuclear magnetic resonance spectrometry (NMR) revealed the presence of phosphocholine in Fractions I and II and apparent near absence from Fractions III and IV but otherwise similar compositions. Phosphorus-31 NMR revealed markedly varying ratios of phosphoryl substituents. Fractions I to IV contained progressively lower ratios of phosphorylcholine to other phosphodiester-linked components, notably phosphoryl- N -methylethanolamine, phosphorylethanolamine, and as-yet-unidentified phosphoryl substituents. These differences between glycopeptide fractions in phosphoryl substituents appeared consistently in preparations from cultures grown upon a wide variety of media, and seem the major features distinguishing the chromatographically separated glycopeptide species.
Novel programmable built-in current-sensor for analog, digital and mixed-signal circuits

The paper presents a novel programmable BICS topology in IBM 65 nm CMOS technology. Programmability, which is the main motivation of this approach, is shown on three different CUTs, simultaneously. It is shown that proposed topology has 473 MHz bandwidth, 200.6ps detection time with 1.5µA sensitivity. Moreover, these specifications are achieved with only one control pin. The advantage on area overhead becomes more significant, as the number of CUTs increases in the system. These results show that proposed programmable BICS is superior when it is compared with recent works.
Research and Solutions: Sustainable Urban Governance: Lessons from Katrina and the Lean Six Sigma

Discussions about sustainability are often confined to the subject of natural resources, such as water and fossil fuels, and how to preserve them for the future. This is too limited, particularly in the case of cities, which depend on other resources for their existence. These resources include man-made public assets, defined by this author as flood control levees, roads, water supply and sewerage systems, bridges, roads, other urban infrastructure, and monetary wealth. A major threat to the sustainability of cities is the decline of public assets and the inability of governments to maintain them for generations to come. A case in point is the broken levees in New Orleans after Hurricane Katrina. Other examples from around the world demonstrate that such failures of infrastructure and government are epidemic. These problems cannot be solved by merely applying green technology. This article proposes a system of sustainable urban governance, based on the concepts of Lean Six Sigma, a structured problem-solv...
Iron oxidation and its impact on MR behavior

The oxidation of particles in MR fluids and its impact on rheology are investigated. The oxidation of iron spheres in an aliphatic oil follows a linear growth law, suggesting that the oxide forms a nonadherent layer. The magnetic field-induced yield stress decreases with increasing extent of oxidation. The rheological behavior is consistent with that predicted using a core-shell model.
Rubber‐modified polystyrene impact as a function of flame‐retardant additive solubilization

Thermal optical analysis (TOA) is employed to study the solubilization of organic flame-retardant additives in high-impact polystyrene. The TOA approach (1) indicates the minimum temperature at which solubilization will occur; (2) yields information on how the composite will process; and (3) can be used to generate an equation that describes the kinetics of solubilization. Multiaxial impact strength increases proportionally as additive solubilization increases. The fundamental significance of the kinetic equation is discussed. Other applications of TOA are suggested.
Inhibin and activin modulate transforming growth factor-β-induced immunosuppression

Inhibin, activin, and transforming growth factor β (TGFβ) inhibited lipopoly-saccharide (LPS)-induced lymphocyte proliferation in a dose-dependent fashion. These induced suppressions were neutralized by coincubation of a preparation of antibodies to inhibin and TGFβ, respectively. Inhibin and activin also facilitated TGFβ-mediated immunosuppression of LPS-induced proliferation of splenocytes. These gonadal proteins showed no effect on phytohemagglutinin-or concanavalin A (Con-A)-induced proliferation of lymphocytes. However, inhibin facilitated and activin inhibited the TGFβ-mediated immunosuppression in thymocytes stimulated by Con-A. These findings suggest that inhibin or activin by itself, and/or together with TGFβ, may play an important role in immune response.
Comorbidities of Diabetes and Hypertension: Mechanisms and Approach to Target Organ Protection

Up to 75% of adults with diabetes also have hypertension, and patients with hypertension alone often show evidence of insulin resistance. Thus, hypertension and diabetes are common, intertwined conditions that share a significant overlap in underlying risk factors (including ethnicity, familial, dyslipidemia, and lifestyle determinants) and complications. These complications include microvascular and macrovascular disorders. The macrovascular complications, which are well recognized in patients with longstanding diabetes or hypertension, include coronary artery disease, myocardial infarction, stroke, congestive heart failure, and peripheral vascular disease. Although microvascular complications (retinopathy, nephropathy, and neuropathy) are conventionally linked to hyperglycemia, studies have shown that hypertension constitutes an important risk factor, especially for nephropathy. The familial predisposition to diabetes and hypertension appears to be polygenic in origin, which militates against the feasibility of a "gene therapy" approach to the control or prevention of these conditions. On the other hand, the shared lifestyle factors in the etiology of hypertension and diabetes provide ample opportunity for nonpharmacologic intervention. Thus, the initial approach to the management of both diabetes and hypertension must emphasize weight control, physical activity, and dietary modification. Interestingly, lifestyle intervention is remarkably effective in the primary prevention of diabetes and hypertension. These principles also are pertinent to the prevention of downstream macrovascular complications of the two disorders. In addition to lifestyle modification, most patients will require specific medications to achieve national treatment goals for hypertension and diabetes. Management of hyperglycemia, hypertension, dyslipidemia, and the underlying hypercoagulable and proinflammatory states requires the use of multiple medications in combination.
On the interaction of palladium with olefinic systems

We have performed all electron Hartree–Fock gradient calculations and geometry optimizations on systems composed of one to three palladium atoms and: CH3 cation and anion, C2H4, C2H3NH2, C4H4, NH3, and (NH3) + (C2H4). Several basis set considerations are discussed and the binding energies of Pd to these small molecules are reported. We find the counterpoise correction to the binding energies of these systems to be large. We also present MP2 calculations of the palladium binding energy with a large uncontracted palladium spd basis set in the PdC2H4 and PdNH3 systems. The binding interaction between ethylene and palladium results in a mixing of the 4d–π* and 5s–π orbitals, and, is dissociative to the ethylene. The palladium-butadiene and palladium-cyclobutene relative stabilites and structures are interesting since these molecules could form from acetylene on a palladium surface. We find the Pd-butadiene cyclic structure to be 43 kcal/mol more stable than the Pd-cyclobutene product.
MINORITIES IN GEOGRAPHY: SOME DISTURBING FACTS AND POLICY MEASURES∗

This study reveals some disturbing facts about the status of minorities in geography in the United States. The three underrepresented minority groups comprise only about 3% of the total geography p...
Administrative Slavery in the Ancient Roman Republic: The Value of Marcus Tullius Tiro in Ciceronian Rhetoric

Urban slave life in ancient Rome was unlike the absolute bondage and physical labor historically associated with the term slavery. Cicero's administrative slave Tiro was a literary collaborator, a debt collector, a superintendent of sorts, a secretary, a financial overseer, a political strategist, a recipient and content-generator of Cicero's famed practice of letter-writing, and a connected component of Cicero's social scheming. Cicero's correspondence with Tiro praises him for his value and loyalty, but it also shows previously unrevealed rhetorical aspects of the ancient orator and his relationship with his slave, colleague, and friend.
Oxidized Low-Density Lipoprotein–Dependent Endothelial Arginase II Activation Contributes to Impaired Nitric Oxide Signaling

Oxidized low-density lipoprotein (OxLDL) impairs NO signaling and endothelial function, and contributes to the pathogenesis of atherosclerosis. Arginase reciprocally regulates NO levels in endothelial cells by competing with NO synthase for the substrate l-arginine. In human aortic endothelial cells, OxLDL stimulation increased arginase enzyme activity in a time- and dose-dependent manner. Arginase activity reached its maximum as early as 5 minutes, was maintained for a period of more than 48 hours, and was associated with a reciprocal decrease in NO metabolite (NOx [nitrite and nitrate]) production. Furthermore, OxLDL induced arginase II mRNA expression after 4 hours. Small interfering RNA targeted to arginase II decreased both the quantity and the activity of arginase from baseline, prevented OxLDL-dependent increases in arginase activity, and induced an increase in NOx production. Immunofluorescence analysis revealed an association of arginase II with the microtubule cytoskeleton. Microtubule disruption with nocodazole caused a dramatic redistribution of arginase II to a diffuse cytosolic pattern, increased arginase activity, and decreased NOx production, which was restored in the presence of the specific arginase inhibitor ( S )-(2-boronoethyl)-l-cysteine (BEC). On the other hand, epothilone B prevented microtubule disruption and inhibited OxLDL-dependent increases in arginase activity and attenuated OxLDL-dependent decreases in NOx. Preincubation of rat aortic rings with OxLDL resulted in an increase in arginase activity and a decrease in NOx production. This was reversed by arginase inhibition with the BEC. Thus, OxLDLs increase arginase activity by a sequence of regulatory events that involve early activation through decreased association with microtubules and a later increase in transcription. Furthermore, increased arginase activity contributes to OxLDL-dependent impairment of NOx production. Arginase, therefore, represents a novel target for therapy in atherosclerosis.
The Company File Project

The Company File Project is a group-oriented, semester-long research exercise in which students are expected to gather and analyze data pertaining to a U.S.-based, publicly traded corporation and to tie this information to the managerial topics covered in the textbook and lecture. Students who participate in the company research project express overwhelming support for the continued use of the company file. They find that the project increases their understanding of managerial concepts and allows them the benefits of meeting and working with many different people.
A screening method for large information retrieval systems

This paper is addressed primarily to describing a method for reducing the excessive processing times sometimes encountered in large information retrieval systems. Two tools are suggested: (1) a screening system to allow multi-level processing of material and (2) pre-processing of the files to allow block rejection of documents not answering a retrieval request.A screen using descriptors to constitute the first level of screening is described in detail, and a pre-processing technique, based upon clustering of descriptors, is developed. Two methods of implementation on high-speed data processors are described based on serial access type storage and random access "dynamic storage," respectively.This screening technique is compared for efficiency against two other familiar methods of employing descriptors: the ordinary serial descriptor list method and the inverted file technique.
The characterization of a cyclic-di-GMP (c-Di-GMP) pathway leads to a new tool for studying c-Di-GMP metabolic genes.

Second messengers play an integral role in regulating a wide variety of pathways in response to triggers from the extracellular milieu. The intracellular second messenger cyclic diguanylate (c-di-GMP) has been shown to regulate microbial adaptation to extracellular environments in myriad ways. Primarily studied in Gram-negative bacteria thus far, c-di-GMP regulates motility, biofilm formation, virulence, and more (reviewed in references 1 to 3). Specifically, elevated c-di-GMP favors a sessile lifestyle, often stimulating biofilm formation. Conversely, reduced c-diGMPpromotesbiofilmdispersalandmotility,andlowc-di-GMP can activate virulence pathways in numerous bacterial pathogens. Incomparison,littleisknownaboutthefunctionsofc-di-GMPin Gram-positive bacteria. Determining how and under what circumstances bacteria regulate c-di-GMP levels, and the outcomes ofc-di-GMPmodulation,isimportantforunderstandingtherole ofc-di-GMPinbacterialcellsignalingandadaptationtochanging extracellular cues. Yet a full appreciation of c-di-GMP signaling pathways is often hindered by the fact that many bacterial genomesencodemultiple,sometimesseveraldozen,c-di-GMPsyn
Use of Electrophoretic Karyotyping in the Evaluation of Candida Infections in a Neonatal Intensive-Care Unit

OBJECTIVE To evaluate a possible common-source outbreak of Candida infections in the neonatal intensive-care unit. Systemic Candida infections increased from 6 to 11 cases (0.71 to 1.34 per 1,000 patient-days). In addition, Candida parapsilosis infections increased from 1 in 1992 to 10 in 1993. DESIGN AND SETTING Tertiary-care, teaching, pediatric institution with a 40-bed neonatal intensive-care unit (NICU). Clinical characteristics, associated conditions, and antimicrobial therapy were obtained from the medical records of all NICU patients with positive blood cultures for Candida during 1992 and 1993. Nineteen Candida isolates from 15 infants were studied retrospectively using contour-clamped homogeneous electric-field (CHEF) electrophoresis. RESULTS CHEF revealed eight karyotypes of C parapsilosis. Five isolates recovered from four patients shared one karyotype. The remaining isolates from seven infants all had distinctly different karyotypes. CONCLUSIONS The evidence was insufficient to implicate a single source of infection, even though four patients in the same unit had identical strain types. However, identical strains of C parapsilosis were associated geographically, suggesting that nosocomial acquisition of C parapsilosis through indirect patient contact in the NICU was possible. The CHEF technique yields unique patterns that may be used to delineate clinical isolates and to study the molecular epidemiology of candidal infections.