cssi/SciSciGPT-SciSciNet huggingface dataset:
Business Students' Choice of Short-Term or Long-Term Study Abroad Opportunities.

Recent years have seen a proliferation of short-term study abroad opportunities. Although they are both supplementing and replacing semester-long study abroad programs, research has focused primarily on semester (long-term) programs. We draw on the theory of planned behavior (TPB) to explore factors that predict why students choose long-term and short-term programs. Results indicate that students perceive more social pressure to engage in short-term programs, and higher barriers limiting participation in long-term programs. All TPB factors significantly predicted students' intentions to study abroad in both short-term and long-term programs with one exception; perceived behavioral control did not significantly predict intentions to participate in short-term programs. These findings can be used to improve marketing of short-term and long-term programs by addressing student concerns specific to each type of program, potentially increasing the number of students choosing to study abroad.
Imide-Aryl Ether Ketone Block Copolymers

Imide-aryl ether ketone block copolymers were prepared and their morphology and thermal and mechanical properties investigated. The key feature of this copolymerization is the preparation of soluble aryl ether ketimine oliogmers which may be subsequently hydrolized to the aryl ether ether ketone form. A bis(amino) aryl ether ketimine oligomer was prepared via a nucleophilic aromatic substitution reaction with a molecular weight of 6,000 g/mol. The oligomer was co-reacted with 4,4′-oxydianiline (OI)A) and pyromcllitic dianhydride (PMDA) diethyl ester diacyl chloride in N-methyl-2-pyrrolidone (NMP) in the presence of N-methylmorpholine. The copolymer compositions, determined by H-NMR, of the resulting amic ester based copolymers ranged from 8 to 20 wt% aryl ether ketimine content. Prior to imide formation, the ketimine moiety of the aryl ether ketimine block was hydrolyzed (p-toluene sulfonic acid) to the ketone form producing the aryl ether ether ketone block. Solutions of the copolymers were cast and cured to effect imidization, producing clear films. The copolymers displayed good thermal stability with decomposition temperatures in excess of 450 °C. Multiphase morphologies were observed irrespective of the co-block type or composition.
Improving online class forums by seeding discussions and managing section size

Discussion forums are an integral part of all online and many offline courses. But in many cases they are presented as an afterthought, offered to the students to use as they wish. In this paper, we explore ways to steer discussion forums to produce high-quality learning interactions. In the context of a Physics course, we investigate two ideas: seeding the forum with prior-year student content, and varying the sizes of "sections" of students who can see each other's comments.
Modulating the Copper-Sulfur Interaction in Type 1 Blue Copper Azurin by Replacing Cys112 with Nonproteinogenic Homocysteine.

The Cu–SCys interaction is known to play a dominant role in defining the type 1 (T1) blue copper center with respect to both its electronic structure and electron transfer function. Despite this importance, its role has yet to be probed by mutagenesis studies without a dramatic change in its T1 copper character. We report herein replacement of the conserved Cys112 in azurin with the nonproteinogenic amino acid homocysteine. Based on electronic absorption, electron paramagnetic resonance, and extended X-ray absorption fine structural spectroscopic studies, this variant displays typical type 1 copper site features. Surprisingly, instead of increasing the strength of the Cu–sulfur interaction by the introduction of the extra methylene group, the Cys112Hcy azurin showed a decrease in the covalent interaction between SHcy and Cu(II) when compared with the WT SCys–Cu(II) interaction. This is likely due to geometric adjustment of the center that resulted in the copper ion moving out of the trigonal plane defined by two histidines and one Hcy and closer to Met121. These structural changes resulted in an increase in reduction potential by 35 mV, consistent with lower Cu–S covalency. These results suggest that the Cu–SCys interaction is close to being optimal in native blue copper protein. It also demonstrates the power of using nonproteinogenic amino acids in addressing important issues in bioinorganic chemistry.
Experimental Canine Cholera II. Production by Cell-free Culture Filtrates of Vibrio cholerae

In an effort to increase the percentage of dogs developing experimental canine cholera [1], variations in the inoculation procedure and in the method of growing Vibrio cholerae were studied. Employed in these investigations was a known "toxin'^producing strain of Vibrio cholerae, Inaba 569B.i When grown under specified conditions, this strain produces heat-labile toxins which bring about the collection of fluid in ligated loops of rabbit ileum [2, 3], produce diarrhea and death in infant rabbits [4, 5] and cause an increase in vascular permeability when injected into the skin of guinea pigs or rabbits [6, 7]. Purification of these toxins has not yet been accomplished. The present paper will describe the production of cholera in dogs challenged with V. cholerae, Inaba 569B, grown under varying cultural conditions. Whereas the percentage of dogs developing cholera following inoculation of 5-6-hr cultures of this strain was 407o, this rate was increased to 807o when 24-hr cultures, grown under different conditions, were used for inoculation.
Marketing and non-marketing materials sent by American Colleges and Universities

This report discusses educational marketing materials used by admissions offices in a random sample of 858 American colleges and universities. Information requested and received by a potential student is described and classified as marketing or non-marketing. This paper shows why four-year institutions and those offering higher degrees are significantly more likely than two-year colleges to use marketing materials in their responses to prospective students. The value of these findings for admissions offices and marketing specialists are presented.
Signal-to-noise improvement in derived images

A method which improves the signal-to-noise ratio in derived images is discussed. It is shown that if the derived images are filtered appropriately it may be possible to improve the signal-to-noise ratio considerably. The advantage of the current method over low-pass filtering is that one may be able to retain some of the high spatial frequency detail in the processed images. The method is applied to the mapping of molecular diffusion constant by NMIR imaging. 1.
Programmed feeding as a model of chronic alcoholism in the rat.

Programmed-feeding polydipsia results in a reliable model of chronic alcoholism in the rat. High oral ethanol consumption and a predictable withdrawal reaction associated with audiogenic seizures are produced. The maintenance of high blood ethanol levels for three weeks in 18 male Charles River rats was associated with audiogenic seizures after 6 to 8 hours of withdrawal. These chronic alcoholic rats had enhanced blood clearance of ethanol. The cerebral cortical crude mitochondrial function showed a decrease in total and magnesium-dependent adenosine triphosphatase activity in alcoholic and control (water-fed) rats compared with normal rats.
Toxoplasma gondii: growth in ovine fetal kidney cell cultures

Serial, in vitro passage of Toxoplasma gondii (Rh strain) was successfully performed in a cell line derived from ovine fetal kidney cells. Invasion of this parasite into the kidney cells was easily discernible 1 hr after inoculation. The subsequent proliferation of the parasite was followed in the cytoplasm of the kidney cells. Very active endodyogeny and rosette formations, as many as 13 in a cell, were observed in the cytoplasm of the kidney cells 48 hr postinoculation. After 96 hr of incubation, the parasite population had increased about 132-fold. The virulence of T. gondii against mice was not attenuated after 2 years of in vitro growth which represented 100 serial passages through the kidney cell cultures. Although no "exotoxin" was produced by T. gondii grown in vitro, a Toxoplasma sp. agar gel immunodiffusion test antigen was isolated from the cell-free supernatant fluid of the kidney cell cultures which was identical to an antigen isolated from "toxogenic" organisms harvested from infected mice.
Vertical gas-solid transition flow with electrostatics

Abstract Choking in vertical pneumatic transport in the presence of electrostatics was examined using a 0.0254 m dia. plexiglas tube and 150 μm dia. glass particles. Electrostatics was found to make the choking transition more violent and occur at a higher air velocity.
Are Current Molecular Dynamics Force Fields too Helical

Accurate force fields are essential for the success of molecular dynamics simulations. In apparent contrast to the conformational preferences of most force fields, recent NMR experiments suggest that short polyalanine peptides in water populate the polyproline II structure almost exclusively. To investigate this apparent contradiction, with its ramifications for the assessment of molecular force fields and the structure of unfolded proteins, we performed extensive simulations of Ala(5) in water ( approximately 5 micros total time), using twelve different force fields and three different peptide terminal groups. Using either empirical or density-functional-based Karplus relations for the J-couplings, we find that most current force fields do overpopulate the alpha-region, with quantitative results depending on the choice of Karplus relation and on the peptide termini. Even after reweighting to match experiment, we find that Ala(5) retains significant alpha- and beta-populations. In fact, several force fields match the experimental data well before reweighting and have a significant helical population. We conclude that radical changes to the best current force fields are not necessary, based on the NMR data. Nevertheless, experiments on short peptides open the way toward the systematic improvement of current simulation models.
The satisfaction of patients with multiple sclerosis regarding services received from physical and occupational therapists

The purpose of this study was to describe the satisfaction of patients with multiple sclerosis regarding the services they received from their physical and occupational therapists. Eighty-one patients volunteered for the study in response to advertisements and completed the Therapist Evaluation Form (TEF). Subjects had to have been a physical or occupational therapy patient within the last year and also had to have seen the same therapist for a minimum of four treatment visits. Total score and item analysis of the results demonstrated a high degree of satisfaction among the patients surveyed. The content of two open-ended questions on the TEF also showed that patients value therapist characteristics of being friendly and caring. Patients reported less satisfaction with the therapists' technical skills as opposed to rapport issues. These results reinforce the literature, which cites the importance of interpersonal aspects of patient/professional relationships for persons with disabilities. In addition, the initial reliability and validity data on the TEF obtained in this study support its further development as an instrument to measure patient satisfaction in physical and occupational therapy.
Characteristics of HIV-infected men with low serum testosterone levels.

Low levels of serum testosterone may have negative implications on morbidity in HIV-infected men. The purpose of this study was to determine demographic and clinical characteristics that predict low serum testosterone among men attending our HIV clinic. A cross-sectional study of 587 HIV-positive male patients who presented at the Louisiana State University HIV Outpatient (HOP) Clinic between August 1997 and January 1999 was conducted. Demographic and clinical characteristics were collected and analysed. Of the 587 men studied, 119 (20.3%) had a serum testosterone level below 400ng/dl. Significantly more men with low serum testosterone levels had a presence of opportunistic infection (especially HIV wasting syndrome, oesophageal candidiasis, or dementia), CD4+ cell counts below 200 cells/mm3, or were taking megestrol acetate. Early detection of low serum testosterone will allow for expedient testosterone supplementation therapy, which could improve morbidity and quality of life for HIV-infected men.
Interrelationships between selected mechanical properties of individually‐tested polymeric fibers

Determination des proprietes de traction et de torsion (angle de torsion a la rupture, contrainte a la rupture, energie de rupture, module secant, a la duree de vie a la flexion) de fibres non traitees. Discussion des resultats
China's New Provincial Leaders: Major Reshuffling Before the 17th National Party Congress

This article surveys the profiles of current provincial leaders in order to determine the possible provincial reshuffling that may occur as a result of on-going elections for provincial Party committees in China. This is a politically significant exercise because the two chief leaders of each provincial unit — the provincial Party Secretary and the provincial governor — will likely enter the 17th Central Committee of the Chinese Communist Party in 2007 as full members. The stakes are even higher for provincial units with a seat in the Politburo because the Party Secretary of the provincial unit will probably enter the 17th Politburo.
Shark-IA: An Interference Alignment Algorithm for Multi-hop Underwater Acoustic Networks with Large Propagation Delays

A fundamental issue of underwater acoustic (UWA) communications is large propagation delays due to water medium. A new direction to address this issue is to take advantage of large propagation delays rather than enduring them as a disadvantage. Recent advances in time-based interference alignment (IA), or propagation delay (PD)-based IA, offer a new potential to turn the adverse effect of large propagation delays into something that is beneficial to throughput improvement. The goal of this paper is to investigate PD-IA in a multi-hop UWA network. We develop an analytical PD-IA model with a set of constraints that guarantee PD-IA feasibility at the physical layer. Based on this model, we develop a distributed PD-IA scheduling algorithm, called Shark-IA, to maximally overlap interference in a multi-hop UWA network. Simulation results show that Shark-IA algorithm can improve throughput performance when compared to an idealized benchmark algorithm with perfect scheduling and zero propagation delay. Further, the throughput gain increases with the amount of interference in the network.
Aggression, gender, and ethnicity

Research that considered separately the genders of the perpetrator and target of aggression found aggression and gender to be related in a number of ways. In several studies using multiple measures, men reported that they had behaved more aggressively than women, had been the target of more aggression from others, and had received more aggression from other males than from females. In other studies, respondents' evaluations of aggressive behavior and beliefs about whether others should behave aggressively were different depending on gender of the potential aggressor and target. Although these general tendencies were found for Anglos, African Americans, and Hispanics, ethnicity and other variables sometimes interacted with gender to influence aggression. These results are consistent with a view of aggressive behavior as influenced by individual, contextual, and cultural variables.
Gray-matter abnormalities in deficit schizophrenia

Deficit schizophrenia (D-SZ) has been proposed as a putative disease subtype defined by prominent, primary negative symptoms that endure as trait-like features during periods of clinical stability. In this study, we acquired magnetic resonance images of the whole brain using a 1.5 T scanner in 19 outpatients with D-SZ, 31 with non-deficit schizophrenia (ND-SZ), and 90 healthy adults. Voxel-based morphometry was used to investigate differences in regional gray-matter volume (GMV) between outpatients with D-SZ and ND-SZ, and between the combined patient subgroups and healthy adults. Compared to healthy adults outpatients with schizophrenia showed GMV reductions, especially in left frontal and temporal cortices and in the left insula. The D-SZ subgroup showed reduced GMV in the insula bilaterally and in the left superior frontal, middle temporal and occipital gyri. Regions in which GMV reductions best distinguished D-SZ from ND-SZ patients included the superior frontal gyrus (Brodmann area 8) and superior temporal gyrus (Brodmann areas 22, 38) bilaterally, the left supplementary motor area (Brodmann area 6), left anterior cingulate, left cuneus and right putamen. These results suggest that patients with deficit schizophrenia have brain abnormalities that differ from those of patients with non-deficit schizophrenia. Further, the neuroanatomic differences between these two putative subtypes of schizophrenia involve brain regions that appear to be associated with the negative symptoms that define the deficit syndrome of schizophrenia.
Reproductive biology of Cyprinella camura, the bluntface shiner, in Morganfork Creek, southwestern Mississippi

– I collected bluntface shiners, Cyprinella camura, once or twice monthly from February to November 1991 in Morganfork Creek, southwestern Mississippi. Examinations of mean largest oocyte diameter (LOD), female mean relative gonadal index (RGI), ovarian developmental condition, and male secondary sexual characteristics indicated that C. camura spawned from late March through mid-August. There were significant positive correlations between mean LOD and mean daylength, mean maximum temperature, and mean minimum temperature (environmental variable means were calculated for the 28 day period prior to each sampling date). Mean day length and mean RGI were significantly positively correlated, but there was no significant relationship between mean maximum and minimum temperatures and mean RGI. Clutch size, RGI, and mean mature oocyte diameter (MMOD) of mature females were significantly correlated with length (standard length). Mean length, clutch size, and RGI of mature females in individual collections decreased significantly over the reproductive season. The corresponding decrease in mean MMOD was not significant.
Micro-channel evaporator for space applications – 2. Assessment of predictive tools

Abstract This study is the second part of a two-part study addressing the effectiveness of micro-channel evaporators for space applications. The first part provided pressure drop and heat transfer data for FC-72 that were acquired with a test module containing 80 of 231 μm wide × 1000 μm deep micro-channels. The tests were performed in three flow orientations: horizontal, vertical upflow and vertical downflow over broad ranges of mass velocity and heat flux. The present part uses these experimental results to assess the accuracy of published predictive tools. The two-phase heat transfer coefficient data are compared to predictions of 15 popular correlations, and pressure drop data to 7 mixture viscosity relations used in conjunction of the Homogeneous Equilibrium Model ( HEM ), and 18 correlations based on the Separated Flow Model ( SFM ). These models and correlations are carefully assessed in pursuit of identifying the most accurate tools. In addition, three important criteria for implementing micro-channel flow boiling in space systems are proposed: avoiding large pressure drop, avoiding critical heat flux (CHF), and negating the influence of body force. It is shown that micro-channels require significantly smaller mass velocities to negate body force effects than macro-channels, and are therefore very effective for space applications.
Role of MT1 melatonin receptors in methamphetamine-induced locomotor sensitization in C57BL/6 mice.

Melatonin modifies physiological and behavioral responses to psychostimulants, with the MT1 and MT2 melatonin receptors specifically implicated in facilitating methamphetamine (METH)-induced sensitization in melatonin-proficient mice. The objective of the study is to assess differences in locomotor sensitization after a single dose of methamphetamine in low-melatonin-expressing C57BL/6 wild-type and MT1 receptor knockout (MT1KO) mice, comparing with melatonin-expressing C3H/HeN mice. Mice received a vehicle or methamphetamine (1.2 mg/kg, i.p.) pretreatment (day 1) during the light (ZT5-9) or dark (ZT 19–21) periods in novel test arenas. Locomotor sensitization was assessed by methamphetamine challenge after an eight-day abstinence (day 9). TH protein expression was evaluated by immunofluorescence and Western blot analysis. Methamphetamine pretreatment induced statistically significant locomotor sensitization upon challenge after eight-day abstinence in C3H and C57 wild-type mice during the light period. The magnitude of sensitization in C57 mice was diminished in the dark period and completely abrogated in MT1KO mice. No differences were observed in tyrosine hydroxylase immunoreactivity in the mesolimbic dopamine system. Additional exposures to the test arenas after methamphetamine pretreatment (nights 2–6) enhanced sensitization. Deletion of the MT1 melatonin receptor abolishes sensitization induced by a single METH pretreatment. The magnitude of sensitization is also altered by time of day and contextual cues. We conclude that the MT1 melatonin receptor is emerging as a novel target of therapeutic intervention for drug abuse disorders.
Stefan George and phonological theory

Ever since Baudouin de Courtenay (e.g. 1917 [1990: 500]), the founder of phonology, it has been customary for every new phonological theory to make claims about the particular level(s) at which rules of versification may refer to phonological representations. Baudouin himself, for example, took rhyming to be evidence of phonemic identity. The birth of generative phonology thus led to a series of claims that rules of versification may have access to underlying representations – or to various intermediate levels of representation more shallow than the underlying but still deeper than phonemic. Starting with Zeps (1963) and for the next twenty-odd years a certain number of such arguments have been published, and it appears that their validity is widely assumed in the field, as reflected in such survey articles as O'Connor (1982: 155–156) and Hayes (1988: 228–229). Presumably it is precisely the widespread acceptance of these arguments that explains the relative lull in the debate recently (but see Malone 1982,1983, 1988a, b).
Why Doesn't the Writing Cure Help Poets?

This paper examines the literature on creative writing and mental illness and relates it to the “writing cure” research that shows that expressive writing improves health. There is an abundance of ...
The Homing Tendency of Shad.

within a few minutes, whereas ryanodine alone ordinarily causes rigor in 3-4 hrs. Ryanodine-ATP injections caused a 9-fold increase in oxygen consumption in the roach, and in one case, where the ATP had been warmed to 450 C and then cooled to room temperature before mixing with the ryanodine, the oxygen consumption was increased to 18 times normal following injection. In the intact roach the ryanodine-ATP effect was reversible in the concentrations used. In the intact frog and the rectus preparations the rigor produced was irreversible. These results strengthen our belief that ryanodine acts specifically on the contractile process in striated muscle and indicate that the mode of action is probably one of interference with the phosphagen-ATP-ADP-actomyosin cycle during contraction.
The morphology and ecology of a new large agglutinated Antarctic foraminifer (Textulariina: Notodendrodidae nov.)

A now genus and species of large (up to 38 mm) arborescent foraminifer was found in abundance (100/m2) in an ice-covered embayment of the Ross Sea, Antarctica. In contrast to highly productive adjacent areas, this oligotrophic embayment is bathed with water coming from beneath the extensive Ross Ice Shelf. Analyses demonstrate no primary productivity and very low bacterial populations in the water column: however, benthic diatom productivity and bacterial populations are substantial. This arborescent foraminifer is well adapted to these unusual conditions. It is of complex construction with a subcentral double-walled bulb, a dendritic root system, and a stem which gives rise to branches. The bulb and root system reside in the sediment. The stem extends from the top of the bulb through from I to 3 mm of sediment into the overlying water, where it terminates in branches. Laboratory and in situ observations have demonstrated that the organism captures bottom sediments, which are brought into suspension by the activities of larger benthic invertebrates, in cytoplasm extending from the branches and stem. Examination of cytoplasmic composition and arrangement indicates that feeding lakes place infrequently.
The Performance of Humor in Computer‐Mediated Communication

This is the author's accepted manuscript. The definitive version is available at www.blackwell-synergy.com.
Cortical activation deficits during facial emotion processing in youth at high risk for the development of substance use disorders.

BACKGROUND: Recent longitudinal studies demonstrate that addiction risk may be influenced by a cognitive, affective and behavioral phenotype that emerges during childhood. Relatively little research has focused on the affective or emotional risk components of this high-risk phenotype, including the relevant neurobiology. METHODS: Non-substance abusing youth (N=19; mean age=12.2) with externalizing psychopathology and paternal history of a substance use disorder and demographically matched healthy comparisons (N=18; mean age=11.9) were tested on a facial emotion matching task during functional MRI. This task involved matching faces by emotions (angry, anxious) or matching shape orientation. RESULTS: High-risk youth exhibited increased medial prefrontal, precuneus and occipital cortex activation compared to the healthy comparison group during the face matching condition, relative to the control shape condition. The occipital activation correlated positively with parent-rated emotion regulation impairments in the high-risk group. CONCLUSIONS: These findings suggest a preexisting abnormality in cortical activation in response to facial emotion matching in youth at high risk for the development of problem drug or alcohol use. These cortical deficits may underlie impaired affective processing and regulation, which in turn may contribute to escalating drug use in adolescence. Language: en
Atometric Rates Read Instantaneously and an Automatic Continuous Recorder for Rate Fluctuation

All types of atmometers in general use, whether of the primitive openpan type or of a type employing a water-impregnated porous material for the evaporating surface (Livingston 'I5), require some time for the securing of a reading, for each reading is simply the difference between the amount of water in the reservoir at the beginning and the amount remaining at the end of an observation period. For ecological and physiological research, including the application of physiology in agriculture and other applied lines, this requirement has not given rise to any serious difficulty, for the usual desideratum is a measure of the mean rate of evaporation occurring from the instrument throughout a considerable time period, and the instrument is conveniently read at the end of each period. Daily rates of evaporation are frequently employed in climatological studies, and intervals longer than a single day suffice in many cases. If we wish weekly means in terms of mean daily rates, we may either read the instrument once each day and take the average of the daily readings as the weekly mean, or we may read the instrument only once a week and divide each reading by seven. Instantaneous readings or records are therefore not generally needed for this kind of study. There are, however, lines of investigation that require records showing the fluctuation of the evaporating power of the air, especially the maximum and minimum for each period, and it has thus far been impossible to meet such requirements except by means of very frequent readings of the atmometers. Of course the momentary rate usually fluctuates in any period, and the mean rate for the period consequently furnishes no information as to the manner of the fluctuations. Automatically recording atmometers of types that furnish readings for short intervals have been devised and operated by several workers but no one has hitherto succeeded in making an instrument to show momentary rates, either with or without a recorder. One form of recording instrument makes a mark on a uniformly advancing strip of paper whenever a volumetric or gravimetric unit of water has been withdrawn from the reservoir, and records thus produced require special plotting by hand if a graph showing rate fluctuations is desired. Another form employs
Measurements of selection on floral traits in black mustard, Brassica nigra

Keywords: Lifetime fitness; multiplicative fitness components; natural selection gradients; path analysis; black mustard; Brassica nigra
Internal standards for survival: increasing the accuracy for human cell mutation assays.

Abstract In mutation and cell transformation assays, it has long been recognized that the common practice of using different numbers of cells on dishes with or without selective conditions creates a source of bias in mutant fraction determination. This is simply because colony formation may be enhanced or suppressed at higher initial cell densities, depending on the assay and agent tested. We propose a solution that consists of the inclusion of an experimentally distinguishable population of cells as an internal standard for colony-forming ability at the high cell density required for detection of rare variants. This method is found to be highly satisfactory for use in measuring mutation to 6-thioguanine resistance in a diploid human B lymphoblast line. For treatment with anti -2,3-dihydroxy-1,10 b -epoxy-1,2,3-trihydrofluoranthene (FDE), N -methyl- N ′-nitro- N -nitrosoguanidine (MNNG), and 4-nitroquinoline-oxide and 4-nitroquinoline-oxide (4NQO), the calculated induced mutant fractions using the internal-standard method were significantly lower than those calculated using the conventional low-density-plating efficiency method. The results of these experiments and our analysis lead us to conclude that this approach is applicable to all single cell mutation of transformation assays and is necessary feature of assays in which an accurate knowledge of the fraction of rare variants is required.
Accumulation of exogenous polyamines in gerbil brain after ischemia

Regionally selective delayed neuronal degeneration is a characteristic sequel of cerebral ischemia. Recent evidence indicates that changes in brain polyamine metabolism may be critical for nerve cell survival after ischemia. Within hours after ischemia, intracellular putrescine levels are greatly increased and remain elevated for days, whereas only minor changes are noted in the levels of the polyamines spermine and spermidine. In contrast, the extracellular levels of all polyamines are low after ischemia. Injections of polyamines following ischemia, however, can protect neurons in the gerbil brain from delayed cell death, with spermine being the most potent of the polyamines. In the present study, therefore, we sought to determine if increased polyamine uptake occurs in the brain after ischemia. In the hippocampal slice preparation, temperature-dependent uptake was unique for spermine, but not for spermidine or putrescine. Uptake of [14C]spermine was transiently increased after ischemia, peaking at 150% of control by 12–13 h and subsiding by 24 h. Intravenous injections of [3H]spermidine resulted in a postischemic accumulation of this polyamine throughout the forebrain parenchyma. We conclude that: 1. Active cellular uptake of spermine is transiently increased early after ischemia; 2. A nonspecific accumulation of exogenous polyamines occurs early after ischemia probably owing to a compromised blood-brain barrier, and 3. The findings indicate that exogenous polyamines can exert their effect directly in the brain after ischemia.
Redox redux: revisiting PTPs and the control of cell signaling

The architecture of the active site of members of the protein tyrosine phosphatase (PTP) superfamily renders these enzymes sensitive to reversible oxidation and inactivation. The importance of reversible oxidation of PTP superfamily members in controlling the signal output following an extracellular stimulus is discussed.
Nathaniel Mackey and the Unity of All Rites

Casual readers perusing the 2006 winner of the National Book Award for poetry probably got quite a surprise when they opened Nathaniel Mackey's Splay Anthem. Their first shock would have come from the eight-page preface, an unapologetic declaration and exposition of the obsessive seriality that has possessed Mackey's poetry since he began publishing it more than twenty years ago. Bristling with neologisms and arcane references, the preface presents Mackey's entwin(n)ed sequences as a practice akin to the poetics of the Kaluli of New Guinea, a poetics that "posits poetry and music as quintessentially elegiac but also restorative, not only lamenting violated connection but aiming to reestablish connection, as if the entropy that gives rise to them is never to be given the last word" (Splay Anthem xvi). Violation and restoration, entropy and connection are precisely what readers would next encounter in the opening of Splay Anthem's first poem, "Andoumboulouous Brush?'mu fifteenth part?":
High-resolution scanning patch clamp: life on the nanosurface.

The cardiomyocyte plasma membrane has 2 jobs: to conduct the action potential along its length and to transduce that action potential into the synchronous increase of cytosolic calcium, which triggers contraction. Ion channels mediate these events at the surface sarcolemma and along highly ordered membrane invaginations known as T-tubules. The types of channels present in the membrane can be identified with immunocytochemistry or electron microscopy, but most are only approximately assigned to specific domains. Moreover, the resulting images likely represent mixed populations of both functional and silent channels, as well as those in reserve pools waiting to be recruited under changing physiological or pathological conditions. Because many disease conditions involve the coordinate perturbation of membrane microstructure and electrical activity, there is much to be learned by probing channel function with greater spatial resolution along the cardiomyocyte. In this issue of Circulation Research , Bhargava et al1 describe a novel method for doing just that and report some surprising discoveries. Article, see p 1112 Scanning ion conductance microscopy2,3 has evolved in recent years to provide a wide range of cellular landscapes reminiscent of the 3-dimensional images of scanning electron microscopy, but in living tissue. The probe is an electrolyte-filled pipette that reports its proximity to the cell membrane as a decrease in conductance. It gets close to the membrane, within a distance equivalent to the internal diameter of the pipette (<100 nm). The probe is lifted and translated (it hops) from 1 point to another along the x and y coordinates, with peaks and valleys registered as different values in the z dimension at which the conductance drops. The result is …
Electrodeposition of CuNiW alloys: thin films, nanostructured multilayers and nanowires

Electrodeposition operating conditions were determined for the deposition of copper–nickel–tungsten alloys and compositionally, multilayered deposits. Multilayered alloys with one layer rich in Cu and the other layer rich in NiW were fabricated as both thin films and nanowires. The electrolyte contained 0.6 M Na3C6H5O7, 0.2 M Na2WO4, 0.3 M NiSO4 and variable CuSO4 concentration at a pH of 8 adjusted with ammonium hydroxide at 70 ± 2 °C. The deposit composition and current efficiency were characterized using rotating cylinder electrodes with and without a Hull configuration. Addition of Cu(II) to the electrolyte lowered the tungsten partial current density and hence the W wt% in the deposit. Thin film multilayered alloys, with a modulation in composition, were fabricated with pulse current deposition and conditions to selectively etch one layer was determined with a view towards fabricating nanotemplates. Nanowires with modulated composition were also demonstrated, electrodeposited into alumina nanoporous templates. However, the nanowire deposition was confounded by the formation of oxide during the modulation, and results herein recommend that the potential of the more noble step be more negative than −0.9 V versus SCE to avoid this situation, despite metallic alloy formation in unrecessed electrodes.
Phorbol Ester Increases Plasminogen Activator Inhibitor Accumulation in Cultures of Human Granulosa Cells

Proteolytic enzymes such as plasminogen activators (PAs) and collagenases are implicated in the process of ovarian follicle rupture. Data obtained in rats support the concept that PAs are both hormonally regulated and temporally related to the ovulatory process; however, such data are lacking in the human ovary. The recent identification of a family of PA inhibitors (PAIs) adds a new dimension to the control of PA activity, and in contrast to animal studies, the human preovulatory follicle is characterized by PA inhibitory activity. To initially examine the PA and PAI system in the human ovary, granulosa cells obtained from women undergoing gonadal hyperstimulation for in vitro fertilization were cultured in the presence or absence of the protein kinase-C activator, phorbol 12-myristate 13-acetate. Reverse fibrin autography of conditioned medium from control cells revealed the presence of a putative PAI with an apparent mol wt of 50,000. Phorbol ester stimulated the accumulation of this PAI in a specific ...
On the effective viscoelastic moduli of two–phase media. III. Rigorous bounds on the complex shear modulus in two dimensions

The translation and the Hashin–Shtrikman methods are used to provide bounds on the effective complex shear modulus of a two-phase two–dimensional viscoelastic composite. They are both given by inequalities that depend on six parameters. The best bounds are obtained by optimizing these parameters over the admissible set, which is larger for the translation method than for the Hashin–Shtrikman method. Consequently, the translation method generally leads to tighter bounds than would be obtained via the standard Hashin–Shtrikman approach. Equivalence classes of two–dimensional viscoelastic composites (directly analogous to similar classes for the pure elastic problem) are found. Combination of the simplified versions of the translation or the Hashin–Shtrikman–type bounds and this equivalency results in simple algorithms for computing tight bounds for any choice of phase moduli and volume fractions. The bounds constrain the effective shear modulus to lie inside a region of the complex plane bounded by arcs of circles. The four points which correspond to the Hashin–Shtrikman–Walpole bounds on the shear modulus of an elastic composite always lie inside or on the boundary of the bounding region. In many cases the bounding region tends to hug the corresponding parallelogram in the complex compliance plane having these four points as vertices.
Removal of Carbonaceous Contamination from SERS-Active Silver by Self-Assembly of Decanethiol.

The presence of carbonaceous contamination on common surface-enhanced Raman scattering (SERS) surfaces has been a primary limitation to the analytical utility of SERS; background contamination sign...
Crystal deposition disease

Calcium pyrophosphate dihydrate crystal deposition disease and HA crystal deposition disease are two common disorders that may come to the attention of a physician because of a variety of clinical symptomatology patterns. In CPPD crystal deposition disease, characteristic radiologic features include articular and periarticular calcification and an arthropathy consisting of joint space narrowing, bone sclerosis, often prominent subchondral cyst formation, occasional severe and progressive destructive bone changes, and variable osteophyte formation. These findings are often seen in a characteristic distribution with involvement of non-weight-bearing as well as weight-bearing joints and with involvement of distinctive intraarticular sites such as the patellofemoral compartment of the knee and the radiocarpal compartment of the wrist. In HA crystal deposition disease, characteristic radiologic features consist of calcific tendinitis and periarthritis as well as a more recently described arthropathy. Awareness of the distinctive roentgenographic appearance of these two diseases should allow a specific diagnosis to be made, and an understanding of their pathologic features should aid in appropriate therapy and guide future investigation of possible etiologic factors.
Deep in budget restraints: return on investment (ROI)

The University of Missouri-Columbia's Information and Access Technology (IAT) Services division's InfoTech Training department measures IT training using the return on investment (ROI) methodology. The ROI measurement estimates a campus-wide financial return in staff productivity through more efficient use of software features. In fiscal year 2002 (July 1, 2001 to June 30, 2002), InfoTech Training's program calculated a 218% ROI.Senior IT management uses ROI methodology in part for resource allocation decisions. ROI measurement is particularly crucial during tight budget times and can help justify the investment in training staff, hardware, software, classroom maintenance, and instructional materials.The InfoTech training manager uses ROI to identify inefficient programs in need of redesign or elimination, and identify successful programs in need of expansion. This paper explores the challenges of: Collecting and Analyzing Data and Determining a Return on Investment.
Ultrashort pulse amplification in Ti:sapphire

Using chirped-pulse amplification in Ti:sapphire, we have generated pulses of 21 fs duration at an energy of 0.5 mJ. We have also demonstrated further amplification of chirped pulses to 45 mJ with a bandwidth capable of supporting 25 fs pulses. The amplifier design minimizes material path-length, spectral distortion and clipping, and compensates for higher-order dispersion by using a combination of prisms and diffraction gratings.
A Microprocessor Based Beam Intensity and Efficiency Display System for the Fermilab Accelerator

The Main Accelerator display system for the Fermilab accelerator gathers charge data and displays it including processed transfer efficiencies of each of the accelerators. To accomplish this, strategically located charge converters monitor the circulating internal beam of each of the Fermilab accelerators. Their outputs are processed via an asynchronously triggered, multiplexed analog-to-digital converter. The data is converted into a digital byte containing address code and data, then stores it into two 16-bit memories. One memory outputs the interleaved data as a data pulse train while the other interfaces directly to a local host computer for further analysis. The microprocessor based display unit synchronizes displayed data during normal operation as well as special storage modes. The display unit outputs data to the front panel in the form of a numeric value and also makes digital-to-analog conversions of displayed data for external peripheral devices.
Density matrix renormalization group algorithms with a single center site

We develop a correction to the density matrix used in density matrix renormalization group calculations to take into account the incompleteness of the environment block. The correction allows successful calculations using only a single site in the center of the system, rather than the standard two sites, improving typical computation times by a factor of two to four. In addition, in many cases where the ordinary density matrix renormalization group method can get stuck in metastable configurations, the correction eliminates the sticking. We test the method on the Heisenberg $S=1$ chain.
The EMG-Force Model of Electrically Stimulated Muscle: Dependence on Control Strategy and Predominant Fiber Composition

The EMG-force relationships of electrically stimulated muscle under a wide range of firing rate and recruitment control strategies were studied in a predominantly slow (soleus) and fast (m. gas-trocnemius) twitch muscles with the objective of applying the results in rehabilitative systems where the EMG serves as a force feedback parameter.
Predictors of Secondary Conditions in a Sample of Independently Living Adults with High-Level Spinal Cord Injury

A sample of 117 Massachusetts adults with predominately high-level spinal cord injuries (SCIs) report a mean of 6.5 (&#453.0) of 17 secondary conditions in the previous year. Hierarchical multiple regression based on a conceptual framework to examine possible contributing factors shows two independent predictors (P &#104 .05) of a greater number of secondary conditions: These predictors are more difficulty with instrumental activities of daily living (IADLs) and more difficulty with accessing medical care. In addition, three variables marginally predicted (P &#104 0.10) more secondary conditions: inadequate access to transportation, tobacco-smoking, and race (white). The findings highlight the importance of IADL difficulty and access to medical care in relation to secondary conditions among adults with SCI.
Buoyancy Induced Flow in a Vertical Internally Finned Circular Duct

Laminar buoyancy induced flow in a vertical internally finned circular tube has been analyzed by numerically integrating the governing partial differential equations. The temperature of the duct is greater than that of the surrounding fluid; hence the density of the fluid inside the duct is less than that of the fluid on the outside, which creates a hydrostatic pressure head across the duct that induces the flow (chimney effect). Results show that despite reduction in the induced flow rate due to increased friction, a finned tube can yield significant heat transfer enhancement compared to a finless tube of the same height. Depending on the parameters, the degree of enhancement can be comparable to the factor by which the heat transfer area increases due to the presence of the fins.
Experimental study of the effect of dielectric and physical properties on temperature distribution in fluids during continuous flow microwave heating

Temperature data was collected at multiple locations in tap water, saltwater, and carboxymethylcellulose (CMC) solutions heated in a continuous flow microwave system by use of custom made temperature measurement system employing a single fiber optic probe. Tap water, 3% saltwater and 0.5% CMC solution were pumped through a 915 MHz continuous flow microwave system operating at 4 kW at three flow rates of 1 lit/m, 1.6 lit/m and 2 lit/m. Saltwater absorbed most power (3940 W) out of the 4000 W incident power, followed by CMC solutions (2690 W) and tap water (2626 W). Cross-sectional temperature distribution patterns showed that saltwater had the most uniform temperature distribution followed by tap water; CMC exhibited a non-uniform temperature distribution due to viscosity changes and thermal runaway effects. The study was very useful in enhancing the understanding of continuous flow microwave heating process for a variety of material properties and flow rates.