cssi/SciSciGPT-SciSciNet huggingface dataset:
Does the prognostic value of dobutamine stress echocardiography differ among different age groups

Background Age is associated with reduced exercise capacity and greater prevalence of coronary artery disease. Whether the prognostic information obtained from dobutamine stress echocardiography (DSE), a stress test commonly used for patients unable to perform an exercise test, provides differential information based on age is not well known. Methods We studied 6,655 consecutive patients referred for DSE. Patients were divided into 3 age groups: (1) 3 months) coronary revascularization. Results Peak stress wall motion score index was an independent predictor of cardiac events in all age groups ( P = .02; 60-74 years: HR 1.70, P P = .006). In patients ≥75 years, peak wall motion score index (HR 1.10, P P = .03) were independent predictors of death. In patients aged 60 to 74 years, abnormal left ventricular end-systolic volume response (HR 1.43, P = .0003) was independently related to death, whereas in patients Conclusions Dobutamine stress echocardiography provided independent information predictive of cardiac events among all age groups and death in patients ≥60 years. However, among patients
Physical and structural studies on the cryocooling of insulin crystals.

Reflection profiles were analyzed from microgravity-grown (µg) and earth-grown insulin crystals to measure mosaicity (η) and to reveal mosaic domain structure and composition. The effects of cryocooling on single-domain and multi-domain crystals were compared. The effects of cryocooling on insulin structure were also re-examined. Microgravity crystals were of larger volume, were more homogeneous and were of higher quality than earth crystals. Several µg crystals contained a single mosaic domain which encompassed all or nearly all of the crystal with an ηavg of 0.005°. The earth crystals varied in quality and all contained multiple domains with an ηavg of 0.031°. Cryocooling caused a 43-fold increase in η for µg crystals (ηavg = 0.217°) and an eightfold increase for earth crystals (ηavg = 0.246°). These results indicate that very well ordered crystals are not completely protected from the stresses associated with cryocooling, especially when structural perturbations occur. However, there were differences in the reflection profiles. For multi-mosaic domain crystals, each domain individually broadened and separated from the other domains upon cryocooling. Cryocooling did not cause an increase in the number of domains. A crystal composed of a single domain retained this domain structure and the reflection profiles simply broadened. Therefore, an improved signal-to-noise ratio for each reflection was measured from cryocooled single-domain crystals relative to cryocooled multi-domain crystals. The improved signal from µg crystals, along with the increase in crystal size, facilitated the measurement of the weaker high-resolution reflections. The observed broadening of reflection profiles indicates increased variation in unit-cell parameters, which may be linked to cryocooling-associated structural changes and disorder.
Performance analysis of power management policies in wireless networks

It has long been recognized that energy conservation usually comes at the cost of degraded performance such as longer delay and lower throughput in stand-alone systems and communication networks. However, there have been very few research efforts in quantifying such trade-offs. In this paper, we develop analytical models to characterize the relationships among energy, delay and throughput for different power management policies in wireless communication. Based on the decision when to put nodes to low-power states, we divide power management policies into two categories, i.e., 1) time-out driven and 2) polling-based. M/G/1/K queues with multiple vacations and an attention span are used to model time-out driven policies while transient analysis is applied to derive the state transition probability in polling-based systems. We find that For time-out driven power management policies, the "optimal" policy exhibits a threshold structure, i.e., when the traffic load is below certain threshold, a node should switch to the low-power state whenever possible and always remain active otherwise. From our analysis, contrary to general beliefs, polling-based policies such as the IEEE 802.11 PSM are not energy efficient for light traffic load
Thiazolidinedione Treatment Decreases Oxidative Stress in Spontaneously Hypertensive Heart Failure Rats Through Attenuation of Inducible Nitric Oxide Synthase–Mediated Lipid Radical Formation

The current study was designed to test the hypothesis that inducible nitric oxide synthase (iNOS)-mediated lipid free radical overproduction exists in an insulin-resistant rat model and that reducing the accumulation of toxic metabolites is associated with improved insulin signaling and metabolic response. Lipid radical formation was detected by electron paramagnetic resonance spectroscopy with in vivo spin trapping in an obese rat model, with or without thiazolidinedione treatment. Lipid radical formation was accompanied by accumulation of toxic end products in the liver, such as 4-hydroxynonenal and nitrotyrosine, and was inhibited by the administration of the selective iNOS inhibitor 1400 W. The model showed impaired phosphorylation of the insulin signaling pathway. Ten-day rosiglitazone injection not only improved the response to an oral glucose tolerance test and corrected insulin signaling but also decreased iNOS levels. Similar to the results with specific iNOS inhibition, thiazolidinedione dramatically decreased lipid radical formation. We demonstrate a novel mechanism where a thiazolidinedione treatment can reduce oxidative stress in this model through reducing iNOS-derived lipid radical formation. Our results suggest that hepatic iNOS expression may underlie the accumulation of lipid end products and that reducing the accumulation of toxic lipid metabolites contributes to a better redox status in insulin-sensitive tissues.
The Importance of Atmospheric Dynamics in the Northern Hemisphere Wintertime Climate Response to Changes in the Earth's Orbit.

Milankovitch proposed that variations in the earth’s orbit cause climate variability through a local thermodynamic response to changes in insolation. This hypothesis is tested by examining variability in an atmospheric general circulation model coupled to an ocean mixed layer model subjected to the orbital forcing of the past 165 000 yr. During Northern Hemisphere summer, the model’s response conforms to Milankovitch’s hypothesis, with high (low) insolation generating warm (cold) temperatures throughout the hemisphere. However, during Northern Hemisphere winter, the climate variations stemming from orbital forcing cannot be solely understood as a local thermodynamic response to radiation anomalies. Instead, orbital forcing perturbs the atmospheric circulation in a pattern bearing a striking resemblance to the northern annular mode, the primary mode of simulated and observed unforced atmospheric variability. The hypothesized reason for this similarity is that the circulation response to orbital forcing reflects the same dynamics generating unforced variability. These circulation anomalies are in turn responsible for significant fluctuations in other climate variables: Most of the simulated orbital signatures in wintertime surface air temperature over midlatitude continents are directly traceable not to local radiative forcing, but to orbital excitation of the northern annular mode. This has paleoclimate implications: during the point of the model integration corresponding to the last interglacial (Eemian) period, the orbital excitation of this mode generates a 1°–2°C warm surface air temperature anomaly over Europe, providing an explanation for the warm anomaly of comparable magnitude implied by the paleoclimate proxy record. The results imply that interpretations of the paleoclimate record must account for changes in surface temperature driven not only by changes in insolation, but also by perturbations in atmospheric dynamics.
THE ROLE OF OFFER RATES IN CONTROLLING SHARING BY YOUNG CHILDREN1

The effects of different reinforcement contingencies on the rates of offers to share and their corresponding rates of acceptance by two small groups of preschool children were investigated in two experiments. In the first experiment, food and praise were given after a 5-min play period to any subject who had made one or more offers to share during the play period. This procedure increased the rate of share-offers by all subjects. However, as share-offers increased, the percentage of offers accepted decreased. In the second experiment, reinforcement was made contingent on a subject reducing offers to share to only one or two per 5-min period. This led to a higher percentage of the offers being accepted. The results suggest that by controlling the rate of a social behavior, the manner in which other persons in the environment respond to the behavior may also be influenced.
All-atom ab initio energy minimization of the kaolinite crystal structure

Calculations that minimize the energy and optimize the geometry of all atomic coordinates for two proposed kaolinite crystal structures were performed using a first-principles, quantum chemical code based on local density functional theory. All calculations were performed using published unit-cell parameters. Inner- and interlayer H atom positions agree well with those determined by Bish (1993) from neutron diffraction data and confirm a unit cell with C1 symmetry.
Work in progress: analysis of reliability of the fluid mechanics concept inventory

A fluid mechanics concept inventory (FMCI) has been developed via a cooperative effort between faculty at the University of Wisconsin-Madison and the University of Illinois, Champaign-Urbana. This concept inventory has been developed to assess student understanding of undergraduate fluid mechanics as taught in mechanical engineering. Now in the third version, the FMCI has been tested in precourse and postcourse assessment. As a result of this testing, the reliability of the inventory is being evaluated through item examination of specific questions included on the FMCI.
MAC Protocol Adaptation in Cognitive Radio Networks: An Experimental Study

This paper presents an adaptive MAC (AMAC) protocol for supporting MAC layer adaptation in cognitive radio networks. MAC protocol adaptation is motivated by the flexibility of emerging software-defined radios which make it feasible to dynamically adjust radio protocols and parameters. Dynamic changes to the MAC layer may be useful in wireless networking scenarios such as tactical or vehicular communications where the radio node density and service requirements can vary widely over time. A specific control framework for the proposed AMAC is described based on the "CogNet" protocol stack which uses a "global control plane (GCP)" to distribute control information between nearby radios. A proof-of-concept AMAC prototype which switches between CSMA and TDMA is implemented using GNU radio platforms on the ORBIT radio grid testbed. Experimental results are given for both UDP and TCP with dynamic traffic variations. The results show that adaptive MAC can be implemented with reasonable control protocol overhead and latency, and that the adaptive network achieves improved performance relative to a conventional static system.
Limits on focused ultrasound for deep hyperthermia

It becomes increasingly difficult for ultrasound to noninvasively heat larger tumor volumes at depth without overheating intervening normal tissues. For a given acoustic window, there exists a maximum tumor volume at a given depth which can be treated effectively without causing lhot spotsr in the normal tissues, even if lidealr applicators and power deposition techniques are applied. In this paper, the upper bound on the radii of treatable spherical volumes under given physical, anatomic, and physiological constraints is determined. Parametric studies are performed to determine relationships between the upper bound radius and constraints such as acoustic window size, tumor depth, attenuation rate, the tolerable temperature in normal tissues, and blood perfusion rate
Photonic crystals from step and flash imprint lithography

Photonic crystals are structures which exhibit a band gap in the electromagnetic spectrum as a result of dielectric periodicity. These structures present the potential to control electromagnetic waves in a similar manner to the way electrons are controlled by semiconductors. To obtain a photonic band gap in a specific region of the spectrum, there are two important characteristics of the photonic crystal that must be considered. The first is the length scale of the periodicity of the crystal, which governs the frequency range in which the band gap falls. The second is the dielectric contrast between the two media which comprise the crystal, which controls the size of the bang gap. Therefore, to construct a photonic crystal which could be used as an optical device, such as a waveguide or filter, the features should be on the order of optical wavelengths, or nanometers. The dielectric contrast through the visible region should also be large enough to open a band gap. Lithography techniques are ideally suited to pattern such structures. This work focused on the use of step and flash imprint lithography as an ideal patterning technology for two dimensional photonic crystals because of its capability for sub-50 nm patterning. Another attractive aspect of using step and flash imprint lithography is the potential to pattern a functional polymer as the crystal. The feasibility of printing structures needed for photonic crystals using imprint lithography was first demonstrated. Then, a strategy to raise the index of refraction of imprint compatible polymer formulations for large dielectric contrast using metal oxide nanoparticles was investigated. A maximum index of n = 1.65 was achieved, but at the high nanoparticle concentrations needed to reach this value, the formulations would not photocure. At low concentrations, imprints were obtained and uses for the resulting moderate index polymer composites as partial band gap photonic crystals were suggested.
Neurotransmitter- and Growth Factor-Induced cAMP Response Element Binding Protein Phosphorylation in Glial Cell Progenitors: Role of Calcium Ions, Protein Kinase C, and Mitogen-Activated Protein Kinase/Ribosomal S6 Kinase Pathway

To understand how extracellular signals may produce long-term effects in neural cells, we have analyzed the mechanism by which neurotransmitters and growth factors induce phosphorylation of the transcription factor cAMP response element binding protein (CREB) in cortical oligodendrocyte progenitor (OP) cells. Activation of glutamate receptor channels by kainate, as well as stimulation of G-protein-coupled cholinergic receptors by carbachol and tyrosine kinase receptors by basic fibroblast growth factor (bFGF), rapidly leads to mitogen-activated protein kinase (MAPK) phosphorylation and ribosomal S6 kinase (RSK) activation. Kainate and carbachol activation of the MAPK pathway requires extracellular calcium influx and is accompanied by protein kinase C (PKC) induction, with no significant increase in GTP binding to Ras. Conversely, growth factor-stimulated MAPK phosphorylation is independent of extracellular calcium and is accompanied by Ras activation. Both basal and stimulated MAPK activity in OP cells are influenced by cytoplasmic calcium levels, as shown by their sensitivity to the calcium chelator bis(2-aminophenoxy)ethane-N,N,N',N'-tetra-acetic acid. The kinetics of CREB phosphorylation in response to the various agonists corresponds to that of MAPK activation. Moreover, CREB phosphorylation and MAPK activation are similarly affected by calcium ions. The MEK inhibitor PD 098059, which selectively prevents activation of the MAPK pathway, strongly reduces induction of CREB phosphorylation by kainate, carbachol, bFGF, and the phorbol ester TPA. We propose that in OPs the MAPK/RSK pathway mediates CREB phosphorylation in response to calcium influx, PKC activation, and growth factor stimulation.
Osmoadaptation and osmoregulation in archaea.

The response of archaea to changes in external NaCl is reviewed and compared to what is known about osmoadaptation and osmoregulation in bacteria and eukaryotes. Cells placed in altered external NaCl exhibit short term and long term responses. The earliest events are likely to be water movement through aquaporin-like channels (efflux if external NaCl has been increased, influx into the cell if the external NaCl has been decreased) and ion movement (e.g., K+ moving in the direction opposite to water flow) through channels sensitive to osmotic pressure. Accumulation of organic solutes, either by uptake from the medium or de novo synthesis, is triggered after these initial changes. Archaea have some unique organic solutes (osmolytes) that are not used by other organisms. These as well as other more common solutes have a role in stabilizing macromolecules from denaturation. Many osmolytes are distinguished by their stability in the cell and their lack of strong interactions with cellular components. A cell may respond by accumulating one or more temporary osmolytes, then over time readjust the intracellular solute distribution to what is optimal for cell growth under the new conditions. Coupled with the movement and accumulation of solutes is the induction of stress proteins (e.g., chaperonins) and, in some cases, transcriptional regulation of key enzymes. The response to NaCl stress of Methanococcus thermolithotrophicus is presented as an example of how one particular archaeon responds and adapts to altered osmotic pressure. Clearly, the detailed response of other archaea to osmotic stress will be needed in order to identify features (aside from some of the organic osmolytes) unique to the organisms in this kingdom.
The Identification of a Glutamic Acid Residue as Part of the Active Site of Ribonuclease T1

Abstract The experiments described in this communication were carried out in order to compare certain aspects of the chemistry of ribonuclease T1 from Aspergillus oryzae with those of bovine pancreatic ribonuclease A. The primary structures of these enzymes of different specificities are known and are very dissimilar; ribonuclease A is a basic protein whereas ribonuclease T1 is acidic. Ribonuclease T1, like the bovine enzyme, is inactivated by reaction with a 180- to 300-fold molar excess of iodoacetate at pH 5.5 and 37°, but not by iodoacetamide. The time for 50% inactivation is 1 hour, which is considerably longer than that for ribonuclease A, and the rate of inactivation is maximal at pH 5.5. Use of 14C-labeled reagent has shown that inactivation is accompanied by the incorporation of 1 carboxymethyl group per molecule of enzyme. The reaction is inhibited by the presence of polyvalent anions such as citrate or phosphate, by metallic cations such as Cu++ or Zn++, and by substrate analogues such as 2'- or 3'-guanylic acids. The inactivation reaction is also inhibited by 8 m urea and thus requires the native three-dimensional structure of the enzyme. Amino acid analyses of acid hydrolysates of the inactivated protein are indistinguishable from analyses of the parent enzyme; hence no reaction has occurred with residues of histidine or lysine which yield acid-stable carboxymethyl derivatives, and which are the sites of alkylation in pancreatic ribonuclease A. One equivalent of glycolic acid can be detected in the hydrolysate. The glycolic acid can be released from the protein by 1 m hydroxylamine at pH 9 in 8 m urea. Upon the working hypothesis that an ester had been formed on the carboxyl group of an aspartic or a glutamic acid residue, the aklylated protein was hydrolyzed by Nagarse to permit chromatographic isolation of a 14C-labeled peptide. The peptide proved to have been derived from Residues 57 to 62: Tyr-Glu-Trp-Pro-Ile-Leu. Hydrolysis of the peptide by aminopeptidase M yielded most of the expected amino acids (but no glutamic acid) plus a new ninhydrin-positive component which has been proved by synthesis to be the γ-carboxymethyl ester of glutamic acid. These experiments establish the presence of a highly reactive γ-carboxyl group at Glu-58 at the active center of ribonuclease T1. The failure of iodoacetamide to inactivate the enzyme indicates that there may be a positively charged group in the molecule which attracts the iodoacetate anion toward the active center and helps to orient the alkylating agent so as to cause the unexpected carboxymethylation of an essential carboxyl group in a glutamic acid residue. The enzyme is inactivated by the relatively small change involved in moving a carboxyl group about 4 A (from —COO- to —COOCH2COO-).
Altered metabolism of progesterone by hepatic microsomes from rats following dietary exposure to polybrominated biphenyls

Abstract Polybrominated biphenyls (PBBs) have produced a variety of effects including alterations in the endocrine system and in activity of microsomal mixed function oxidases (MFOs). Since steroid sex hormones are substrates for MFOs, certain effects of PBBs on the endocrine system may be a consequence of enhanced steroid sex hormone catabolism. Therefore, the purpose of this investigation was to determine the effects of PBBs on hepatic microsomal metabolism of progesterone in vitro. Hepatic microsomes were prepared from rats exposed to 0 or 100 ppm PBBs from Day 8 of gestation until they were killed at 4 (male and female), 12 (male), or 21 (female) weeks of age. Progesterone and its metabolites were identified and quantified utilizing high-pressure liquid chromatography and/or thin-layer chromatography with liquid scintillation spectrometry. Steroid identification was confirmed with gas chromatography/mass spectrometry. Metabolism of progesterone to 16α- or 6β-hydroxyprogesterone was increased by pretreatment with PBBs. Effects of PBBs on progesterone metabolism were dependent on sex. Alterations in metabolism of progesterone by PBBs were compared to effects of phenobarbital or 3-methylcholanthrene. Stimulation of hepatic 16α- and 6β-progesterone hydroxylase following PBBs resembled that produced by phenobarbital. These results support the contention that effects of PBBs on the endocrine system may be due, at least in part, to accelerated metabolism of steroid sex hormones.
Acoustics of attached and unattached flow for simplified OTW configurations with 5:1 slot nozzle

The acoustics of simple engine over-the-wing configurations, with complete and partially attached jet flow to the shielding surface were studied with scale models. The nozzle used consisted of a 5:1 slot nozzle operated at a nominal jet Mach number of 0.6, with the flow directed parallel to and at angles up to 10 deg toward the shielding surface. The flow field at the trailing edge of each nozzle/surface configuration was mapped. the results indicate that, with attached flow, the jet flow field is stretched in the flow direction resulting in locally higher velocities than those for partially attached flow or nozzle only flow. The stretching of the flow field increases the noise levels for the attached flow cases compared to those with only partially attached flow. With attached flow, the shielding benefits are substantially reduced compared with fully detached flow.
Utilizing Self Perception Theory to Explain Social Media Behavior Relative to Print Advertisement 2-D Codes

Marketers are using more traditional marketing channels to drive traffic to the social media platforms. Embedding two-dimensional (“2-D”) barcodes, also known as QR codes, in print advertising is one example. In an effort to provide marketers some guidance on how best to implement such a strategy, reported in this article is the study of the effects of this tactic on consumer response. We draw upon self-perception theory to derive three key insights: 1) the use of 2-D barcodes can elicit pro-brand behavior (snapping), and self-perception of this behavior can enhance attitudes; 2) conversely, a failure to engage in snapping behavior may actually undermine attitudes; 3) any boost in attitudes may be confined to light users of a brand, who do not have strongly established attitudes, and to situations where snapping behavior is perceived to be voluntary, such as when prizes or rewards are absent. Data from two experiments, utilizing two different product category contexts, support this theorizing.
A Brief History of Alcohol Use and Abuse in Human History

There is clear archaeological evidence that dates the production and consumption of alcoholic beverages back ~20,000 years. Over the millennia the techniques of fermenting various organic materials have been gradually refined, and now there are thousands of different alcohol beverages that are produced, both commercially and noncommercially, throughout the world. Mankind’s relationship with alcohol has been decidedly mixed, with its use associated both with celebration and with despair. The perceived salutary effects of alcohol in human culture have been celebrated in song and prose. In contrast, the negative effects of alcohol on behavior have led to its prohibition by various societies and religions since its use first became widespread in human culture many thousands of years ago. Independently of the arguments for and against the ingestion of alcoholic beverages, it is clear that its prohibition in free societies is not only impossible but in fact may also have unintended consequences such as the growth in organized crime and tragic side effects of consuming unsafe homemade products. Therefore, even with a growing public awareness of the adverse consequences of alcohol use and a justifiable tightening of laws that regulate its sale and distribution and punish dangerous alcohol-related activities such as driving while under the influence, it is clear that alcohol consumption will remain common throughout the world for the foreseeable future.
Readmissions after major gynecologic oncology surgery

Abstract Objectives To examine the underlying indications, timing, and risk factors associated with unplanned hospital readmissions after major surgery for a gynecologic malignancy. Methods This is a retrospective database cohort study utilizing the National Surgical Quality Improvement Program database (NSQIP). The association between risk factors with respect to 30-day unplanned readmission was modeled using logistic regression. Timing of readmission and the primary reason of readmission was abstracted from the database. Results Overall, the unplanned readmission rate was 6.5% (832/12,804). On multivariate analysis, operative time≥3h (OR 1.39, p Conclusions Efforts to reduce readmission rates should focus on identifying patients at a high risk of readmission and reducing surgical site infections. Additionally, prospective evaluation of interventions targeted at reducing readmissions should focus on the first two weeks after discharge from the hospital.
Separating the Devil from the Diabolos: A Fresh Reading of Wisdom of Solomon 2:24

The typical English translation of Wisdom of Solomon 2.24 reads: ‘But through the devil's envy death entered the world, and those who belong to his company experience it’ (nrsv). Most scholarship on the passage has taken for granted the devil's place in this text and has understood this verse as one of the first references to the devil as the serpent of the Genesis 3 narrative. Unfortunately, this has given the devil a place in a text where he does not belong. Through philological and textual analyses, this article seeks to give a reading of Wis. 2.24 that is both more congruent to the Greek text and more consistent with the overall worldview of the author. This reading will help to foster greater understanding of such fundamental aspects of this text's ideology as theodicy, soteriology, and its overall conceptions of life and death.
The Rhetoric of Black and White in Othello

black in our language and literature had reached an explosive pitch, I found the preparation of Othello an arduous but illuminating exercise. The repeated use of the terms black and white, with various but always polarized meanings, and the relationship of those terms to other suggested and dramatized elements of the play required, indeed demanded, a full explication of the terms and of Shakespeare's use of them in Othello. Such an explication suggests that the complex and confusing values of black and white are used to reinforce the theme of man's tragic blindness in Othello. The terms black and white have been complex and confusing since the beginning of the language, and Shakespeare seems to have fully exploited their complexity within Othello. According to the OED, the origin of the word black is obscure, but seems to be related to the verb Blaekan, "to burn, or scorch," and is used for that color of charcoal which is the total absorption, or the total absence of light; however, the original term, blac, is so close to bl4c, meaning shining white-the total reflection or presence of light-that the meanings of the two are not always distinguishable,' even by context. This early confusion of the literal, denotative meanings of the terms is a vivid precursor of possible confusions available by Shakespeare's day when both black and white could be accurately used for a wide variety of specific denotations, each with its own range of connotations. Shakespeare not only employed various meanings of the terms and their connotations literally and metaphorically, but also persistently applied the connotations of one meaning of black to another meaning of black. In addition, the conflated and confusing values of black that resulted from this treatment are heightened by a similar treatment of the opposite values of white, or, more often, fair. Within Othello, black is used with five explicit denotations, and white or fair is posed in each instance, either explicitly or by suggestion, as the opposite quality. First, black is used as a color designation for the darkest hue, "an old black ram" (I. i. 88)2; white, as the opposite, designates the lightest hue: "white ewe" (I. i. 89). Second, black. is used to designate a Moor, a Negro, one of
Initial Survey of Arthropod Predators of the European Red Mite in South-Central Pennsylvania

The study was conducted in preparation for intensive examination of some of the principal predators of the European red mite, Panonychus ulmi (Koch), under a USDA, Agr. Res. Serv. grant. The study was necessary, since no list of predators of P. ulmi , in Pennsylvania had previously been compiled.
Cerebrovascular transit characteristics of DyDTPA-BMA and GdDTPA-BMA on normal and ischemic cat brain.

PURPOSE To compare the efficacy of two nonionic T2*-shortening contrast agents, DyDTPA-BMA dysprodiamide injection and GdDTPA-BMA gadodiamide injection, as perfusion-sensitive MR imaging agents in normal and acutely ischemic brain. METHODS The magnetic susceptibility effects of intravenous injections of 0.10-0.50 mmol/kg of each contrast agent were quantified on T2-weighted spin-echo images of cat brain before and after unilateral occlusion of the middle cerebral artery by measuring signal intensity changes in the same regions-of-interest in parietal cortex. RESULTS In normal brain, DyDTPA-BMA produced a significantly greater loss of signal intensity than equimolar doses of GdDTPA-BMA. The magnitude of the signal intensity attenuation was dosage-dependent and proportional to the square of the magnetic moments of the two contrast agents. Restoration of baseline image signal intensity was observed within 30 min after each injection. However, injection of GdDTPA-BMA also produced a delayed, persistent hyperintensity on T2-weighted images, presumably due to its underlying T1-shortening effect. Following unilateral occlusion of the middle cerebral artery, unenhanced T2-weighted images failed to show evidence of cerebral injury for 1.5-3 hours. Administration of 0.10-1.0 mmol/kg DyDTPA-BMA shortened the time for detection of perfusion deficits (residual hyperintensity) in 22 of 36 (61%) treated cats, often to within 30 min after arterial occlusion. DyDTPA-BMA enhancement also improved lesion conspicuity in 26 of 36 (72%) cases, and disclosed very small infarcts that were not visible on T2-weighted precontrast images. Perfusion deficits in areas of partial ischemia were seen more clearly on DyDTPA-BMA-enhanced images than after equimolar injections of GdDTPA-BMA. CONCLUSIONS Magnetic susceptibility contrast-enhanced MR imaging enables detection of perfusion deficits associated with acute cerebral ischemia well in advance of conventional T2-weighted spin-echo MR imaging without contrast. DyDTPA-BMA appears to delineate regions of ischemic damage better than GdDTPA-BMA.
Exercise and beta-adrenergic regulation of rat cardiac myosin isoforms.

Background. The purpose of this experiment was to examine the effects of both exercise and β-adrenergic receptor blockade on the expression of native cardiac myosin isoforms. Specifically, this experiment tested two hypotheses: 1) treatment of sedentary rats with the beta blocker, propranolol, will promote increased ventricular V 3 (slow) native myosin content with a concomitant reduction of V 1 (fast) myosin isoforms; and 2) endurance exercise training will result in an increased sympathetic drive and therefore will retard the propranolol-induced shift in cardiac myosin isoform expression. Methods. Adult, male Sprauge-Dawley rats (120 days old) were randomly divided into 4 groups: 1) exercise-sham (ES); 2) exercise-propranolol (EP); 3) sedentary-sham (SS); and 4) sedentary-propranolol (SP). Propranolol (30 mg drug/kg body wt) and sham (saline) injections (IP) were administered 30 minutes prior to daily exercise. Both ES and EP groups completed six weeks (5 day/wk) of treadmill running at approximately 65-70% VO 2 max. Results. Data analysis revealed that exercise training did not alter (p>0.05) ventricular myosin isoforms in the sham injected animals. In contrast, propranolol treatment resulted in a significant (p<0.05) increase in the slow (V 3 ) myosin isoform and a concomitant decrease in the V 1 isoform in both sedentary and exercise trained animals. Conclusions. The observed increase in V 3 myosin isoform in propranolol treated rats supports the notion that β-adrenergic stimulation is an important regulator of cardiac myosin isoform expression. However, our hypothesis that exercise training would retard the propranolol-induced shift in cardiac myosin was not supported.
Childhood weight status and timing of first substance use in an ethnically diverse sample

Abstract Background We examined associations between weight status during childhood and timing of first cigarette, alcohol, and marijuana use in an ethnically diverse sample. Methods Data were drawn from child respondents of the 1979 National Longitudinal Survey of Youth, including 1448 Hispanic, 2126 non-Hispanic Black, and 3304 non-Hispanic, non-Black (White) respondents aged 10 years and older as of last assessment. Cox proportional hazards regression was conducted predicting age at first use from weight status (obese, overweight, and underweight relative to healthy weight) assessed at ages 7/8, separately by substance class, sex, and race/ethnicity. Tests of interactions between weight status and respondent sex and race/ethnicity were also conducted. Results Compared to healthy-weight females of the same race/ethnicity, overweight Hispanic females were at increased likelihood of alcohol and marijuana use and overweight White females were at increased likelihood of cigarette and marijuana use. Compared to healthy-weight males of the same race/ethnicity, obese White males were at decreased likelihood of cigarette and alcohol use and underweight Hispanic and Black males were at decreased likelihood of alcohol and marijuana use. Significant differences in associations by sex and race/ethnicity were observed in tests of interactions. Conclusions Findings highlight childhood weight status as a predictor of timing of first substance use among Hispanic and Non-Hispanic Black and White female and male youth. Results suggest that collapsing across sex and race/ethnicity, a common practice in prior research, may obscure important within-group patterns of associations and thus may be of limited utility for informing preventive and early intervention efforts.
Value-Based Resource Management in High-Performance Computing Systems

We introduce a new metric, Value of Service (VoS), which enables resource management techniques for high-performance computing (HPC) systems to take into consideration the value of completion time of a task and the value of energy used to compute that task at a given instant of time. These value functions have a soft-threshold, where the value function begins to decrease from its maximum value, and a hard-threshold, where the value function goes to zero. Each task has an associated importance factor to express the relative significance among tasks. We define the value of a task as the weighted sum of its value of performance and value of energy, multiplied by its importance factor. We also consider the variation in value for completing a task at different time; the value of energy reduction can change significantly between peak and non-peak periods. We define VoS for a given workload to be sum of the values for all tasks that are executed during a given period of time. Our system model is based on virtual machines (VMs), where each dynamically arriving task will be assigned to a VM with a resource configuration based on number of homogenous cores and amount of memory. Based on VoS, we design, evaluate, and compare different resource management heuristics. This comparison is done over various simulation scenarios and example experiments on an IBM blade server based system.
Early Management of Severe Thermal Injury

Fluid resuscitation regimens, inhalation injury, and acute gastroduodenal ulceration in the severely burned patient are considered.
Using tablet computers to teach preschool children to write letters

With the increasing popularity of touchscreen devices, using technology to support young children's learning has become more accessible. However, given the relative novelty of tablet computers, the research regarding their effectiveness in education is limited. The current study extends findings of current research demonstrating that tablet computers helped students improve writing, reading, and math abilities of elementary students by examining how tablet computers could support the development of preschool children's writing ability. We explored the effects of two types of feedback afforded by tablet computers: concurrent, extrinsic feedback (i.e., feedback provided by a tablet computer as soon as an error was made) and intrinsic feedback (i.e., naturally occurring sensory information resulting from practicing writing with one's finger). Preschool children (ages 41-65 months) learned to write eight uppercase letters in small groups three times a week for eight weeks in one of three ways: paper and pencil, tablet computer and finger, or tablet computer and stylus. The number of letters correctly written on a paper-and-pencil posttest depended on the instructional condition. Those who practiced writing with a stylus on a tablet computer wrote a similar number of letters correctly at posttest as those who practiced using paper and pencil. This result suggests that concurrent, extrinsic feedback did not provide an additional benefit over the visual feedback in this context. More interestingly, those who practiced writing with their finger on a tablet computer wrote more letters correctly at posttest than those who practiced using a stylus on a tablet computer. This finding indicates that an enhanced tactile experience was more beneficial for learning to write on a tablet computer than increasing the similarity between the practice tasks and the transfer task. However, whether the use of tablet computers is superior to practicing with one's finger on paper worksheets remains an open question. Several future directions are offered. Immediate feedback provided by an iPad did not improve learning to write.Haptic feedback (via a finger on the iPad) was conducive to learning how to write.Preschoolers benefited more from using a finger than a stylus.Tablet computers appear to hold promise for teaching young children how to write.
A Perspective on Catalytic Strategies for Deoxygenation in Biomass Pyrolysis

Biomass fast pyrolysis is a technology that is able to convert biomass, a low-density solid, into primarily a liquid bio-oil product that is denser and more easily storable and transportable. However, utilizing raw bio-oil is difficult, mainly due to its high oxygen content. Bio-oil must be upgraded and deoxygenated first before it can be co-fed into a petroleum refinery. One method of upgrading involves condensing the pyrolysis vapors into bio-oil and then hydrotreating the bio-oil. Significant deoxygenation can be achieved; however, the hydrotreatment is typically performed under high pressure (>6900 kPa) and with multiple temperature stages. Also, lignin-derived phenolic compounds can be prone to polymerize and plug reactors. Generally, the catalysts that have been tested are expensive noble metals or transition metal sulfides. Another upgrading approach is to react the pyrolysis vapors over a catalyst to produce a deoxygenated liquid product upon condensation. Common petroleum refining catalysts, such as zeolites, have been found to produce hydrocarbons although their yields are generally low to moderate whereas the yields of solids (char/coke) and gases (CO and CO2) can be high. In addition, zeolites can suffer rapid deactivation through coking and loss of acidity. Other, new catalysts that have been tested for vapor-phase deoxygenation include noble-metal and transition-metal catalysts. Noble metals are active but are also prone to saturating aromatic rings. More cost-effective catalysts, that is, transition metal-based catalysts, have also been tested for hydrodeoxygenation efficacy. Particularly, two molybdenum-based catalysts, MoO3 and Mo2C, were found to deoxygenate biomass model compounds under low pressure and moderate temperatures. In addition, MoO3 has been shown to deoxygenate pyrolysis vapors obtained from complete biomass. From our perspective, the most feasible upgrading strategy would likely involve catalytically upgrading pyrolysis vapors under low pressure, moderate temperature, and with minimal hydrogen consumption to produce unsaturated alkenes and aromatics, which can then be further processed and refined in a traditional petroleum refinery.
Paradoxes of Restorative Justice in the Workplace

Proponents of restorative justice argue that restorative practices are more effective than legalistic practices at addressing detrimental personal and relational outcomes of hurtful behavior. Follo...
A frequency-shift-filtering approach to cyclostationary noise modeling in MIMO NB-PLC

In this paper, we propose a cyclostationary noise model for multi-input multi-output (MIMO) narrowband power line communication (NB-PLC) based on frequency-shift (FRESH) filtering. The MIMO FRESH filters are designed to shape a multi-input white noise spectrum to a muti-output cyclic spectrum extracted from experimental noise measurements of three-phase low-voltage power lines. The noise modeling problem is formulated as a system identification problem that minimizes the time-averaged mean square error (TA-MSE) between a reference measured noise waveform and the model-generated noise waveform. We propose the normalized mean-square-error (NMSE) for both the cyclic auto-correlation and cyclic cross-correlation between the measured and the generated noise waveforms as a performance measure. The noise waveform generated by the proposed model shows a good agreement with that of the measured noise in terms of the cyclic auto/cross-correlation NMSE. Moreover, the proposed model provides a scalable performance-complexity tradeoff.
Toward political ecologies of environmental education

ABSTRACTDrawing a causal line between educational practice and ecological impact is a difficult intellectual task given the complexity of variables at work between educational event and ecological effect. This is further complicated by the anthropological fact that diverse peoples interact with nature in myriad ways. Our environmental interactions are socially organized and the result of political processes. Dominant approaches in educational research literature pay scant attention to the political-ecological aspects of producing knowledge about the environment, although recent work has begun to challenge such apolitical and acultural research paradigms. We therefore comment on the special issue articles and situate them within larger conversations currently shaping environmental anthropology and human geography. We conclude with considerations for future work toward developing political ecologies of environmental education and its research.
Ligand Design toward Multifunctional Substrate Reductive Transformations

The synthesis of bis(N1-phenyl-5-hydroxypyrazol-3-yl)pyridines ("L") is described, and these are silylated to achieve analogues ("Si2L") without the variable of the hydroxyl proton mobility. One hydroxyl example is characterized in its bis-pincer iron(II) complex, which shows every OH proton involved in hydrogen bonding. The steric bulk of the silylated N-phenyl-substituted ligands allows the synthesis and characterization of paramagnetic (Si2L)FeCl2 complexes, and one of these is reduced, under CO, to give the diamagnetic (Si2L)Fe(CO)2 species. Structural comparison and density functional theory calculations of the dichloride and dicarbonyl species show that much, but not all, of the reduction occurs at both the ligand pyridine and pyrazole rings, and thus this ligand type is more resistant to reduction than the simpler bis(iminopyridines). The OSiR3 substituent offers a useful diagnostic of reduction at pyrazole via the degree of π-donation to pyrazole by the oxygen lone pairs, and the stereoelectronic features of the NPh moiety are analyzed. The X-ray photoelectron spectroscopy binding energies of both iron and nitrogen are analyzed to show details of the locus of reduction.
Serializing the Political Spectrum: Post-9/11 Television, from Left to Right

Abstract:This essay examines post-9/11 television that dramatizes the interplay between proto-leftist and neoconservative political values. These series are able to represent terrorist antiheroes, anti-capitalist utopias, and other radical scenarios because the temporal reach of serial viewing allows for an oscillation across the political spectrum, from left to right.
ϕ Meson Production at Forward Rapidity with the PHENIX Detector at RHIC

The ϕ meson production in p +p collisions is an important tool to study QCD, providing data to tune phenomenological QCD models, while in high-energy heavy-ion collisions it provides key information on the hot and dense state of the strongly interacting matter produced in such collisions. It is sensitive to the medium-induced effects such as strangeness enhancement, a phenomenon associated with soft particles in bulk matter. Measurements in the dilepton channels are especially interesting since leptons interact only electromagnetically, thus carrying the information from their production phase directly to the detector. Measurements in different nucleus-nucleus collisions allow us to perform a systematic study of the nuclear medium effects on ϕ meson production. The PHENIX detector provides the capabilities to measure the ϕ meson production in a wide range of transverse momentum and rapidity to study various cold nuclear effects such as soft multiple parton rescattering and modification of the parton distribution functions in nuclei.In this proceeding, we report the most recent PHENIX results on ϕ meson production in p +p , d +Au and Cu+Au collisions.
Using Super Bowl 2017 Commercials to Teach about Diversity

This paper examines the idea of using advertising to facilitate difficult conversations about diversity, politics, race and gender in the classroom. In our current tense political climate, I explor...