cssi/SciSciGPT-SciSciNet huggingface dataset:
Evaluation of mercury in urine as an indicator of exposure to low levels of mercury vapor.

We conducted a pooled analysis to investigate the relationship between exposure to elemental mercury in air and resulting urinary mercury levels, specifically at lower air levels relevant for environmental exposures and public health goals (i.e., < 50 microg/m3 down to 1.0 microg/m3). Ten studies reporting paired air and urine mercury data (149 samples total) met criteria for data quality and sufficiency. The log-transformed data set showed a strong correlation between mercury in air and in urine (r = 0.774), although the relationship was best fit by a series of parallel lines with different intercepts for each study R2 = 0.807). Predicted ratios of air to urine mercury levels at 50 microg/m3 air concentration ranged from 1:1 to 1:3, based on the regression line for the studies. Toward the lower end of the data set (i.e., 10 microg/m3), predicted urinary mercury levels encompassed two distinct ranges: values on the order of 20 microg/L and 30-60 microg/L. Extrapolation to 1 microg/m3 resulted in predicted urinary levels of 4-5 and 6-13 microg/L. Higher predicted levels were associated with use of static area air samplers by some studies rather than more accurate personal air samplers. Urinary mercury predictions based primarily on personal air samplers at 1 and 10 microg/m3 are consistent with reported mean (4 microg/L) and upper-bound (20 microg/L) background levels, respectively. Thus, although mercury levels in air and urine are correlated below 50 microg/m3, the impact of airborne mercury levels below 10 microg/m3 is likely to be indistinguishable from background urinary mercury levels.
Contracting in Academe: Universities and International Services Entrepreneurship

This research considers the contracting practices of universities to suggest that they are increasingly using practices similar to those used by private sector organizations, which have been the traditional focus of contracting research. Existing theory from the fields of organizational economics, law and entrepreneurship is used to explore the management of international relationships between schools of management. It contends that the pursuit of international relationships is a special case of institutional entrepreneurship. It relies on transactions cost economics (Williamson, 1979) and agency theory (Eisenhardt, 1989) approaches to evaluate the details of agreements between the parties involved in the context of conditions that influence the creation of those agreements. Under this approach, faculty members as agents and educational institutions are principals. Issues that must be considered by institutions and agents who are parties to an exchange, and the types of contractual mechanisms that must be...
Outcome of open massive rotator cuff repairs with double-row suture knotless anchors: case series

The aim of the present study was to evaluate functional and quality of life outcomes after transosseous equivalent (TOE) double row suture technique for massive rotator cuff (RTC) tear repair using validated subjective and objective measures. This technique has shown promising preliminary results in RTC repair; however, a paucity of evidence regarding these outcomes in massive RTC (MRTC) tear repair exists. Patients were identified using the Hospital Inpatient Enquiry Scheme. Pre-operative MRI and medical records were reviewed. A massive RTC tear was defined as the detachment of two or more tendons from their point of insertion on the humeral head. The Constant and Oxford Shoulder Scores (OSS) and SF-12 questionnaire were used for evaluation. Twenty-two patients were studied (72.7 % male; mean age at surgery, 62.6 years). Mean follow up was 14 (range six to 30) months. At six weeks postoperatively, 68 % achieved good or excellent shoulder function as measured by the OSS and Constant score. The cohort’s mean SF-12 physical and emotional scores were significantly lower (p = 0.0002 and 0.037) and the vitality and mental health scores were higher (p = 0.005 and 0.006) than the reference norm scores. The TOE double row surgical repair for MRTC tears provides good to excellent functional outcomes and is associated with high vitality and mental health scores at a mean of 14 months. Physical and emotional scores were lower than reference norm. These results suggest this repair technique is appropriate for massive rotator cuff tears, and future randomised control studies are warranted.
Rapid activation of NF-κB and AP-1 and target gene expression in postischemic rat intestine

Abstract Background & Aims: The molecular mechanisms underlying intestinal mucosal damage-repair processes induced by ischemia-reperfusion (IR) remain unknown. We determined nuclear factor–κB (NF-κB) and activator protein 1 (AP-1) activities and the expression of potential target genes relevant to damage-repair events. Methods: Rat jejunal segment was subjected to ischemia for 30 minutes followed by reperfusion for defined times. NF-κB and AP-1 activities; mucosal p105, p50, and inhibitor κB-α (IκB-α) levels; and c-fos, neurotensin, and ferritin H expression were determined by electrophoretic mobility shift assay and Western and Northern analyses, respectively. Results: NF-κB and AP-1 activities were significantly elevated from 1 to 12 hours after reperfusion. The activated NF-κB in the nuclear extract consisted of solely p50 homodimers. Activation of p50 was associated with a decrease of p105, generation of p50, and increased phosphorylation and degradation of IκB-α. The activated AP-1 contained c-fos but not c-jun, fosB, and Fra-1. Reperfusion induced a transient elevation of c-fos, prolonged increase of neurotensin, and early reduction followed by recovery of ferritin H messenger RNA. Conclusions: The intestine shows organ-specific responses to IR, characterized by prolonged NF-κB and AP-1 activation involving NF-κB p50 dimers and excluding AP-1 c-jun protein. Degradation of the IκB-γ component of p105 and partial reduction IκB-α selectively activate p50/p50 dimers. Temporal patterns of target gene expression reflect functional relevance to mucosal damage-repair processes after IR. GASTROENTEROLOGY 2000;118:525-534
A practical synthesis of the serotonin 5-HT2a receptor antagonist mdl 100907, its enantiomer and their 3-phenolic derivatives as precursors for [11c]labeled pet ligands

A practical synthesis of the 3-phenolic precursor of MDL 100907, a selective 5-HT2A receptor antagonist, is described. The route was also applied to the enantiomeric series, thus affording the direct precursors of both 3-[11C]MDL 100907 and its enantiomer as ligands for positron emission tomography. Similar methodology was developed for the direct synthesis of MDL 100907 and its enantiomer, MDL 100009. The routes utilized classical optical resolution of the N-nor intermediates in at least 98% enantiomeric excess and easily afforded multigram amounts of the chiral precursors of a variety of N- and 3-O-substituted enantiomers.
The effects of slight premixing on fuel decomposition and hydrocarbon growth in benzene-doped methane nonpremixed flames

Abstract Experimental measurements have been made in a series of non-premixed and slightly premixed benzene-doped methane flames to investigate the effect of fuel-side air on soot concentrations and to determine whether the self-reaction of cyclopentadienyl radical is a significant source of naphthalene under these conditions. The flames were generated by adding increasing amounts of primary air to the benzene-doped methane fuel mixture in a co-flowing axisymmetric non-premixed flame. The molar benzene/methane ratio was 2%, which was high enough for the benzene to dominate the production of aromatic hydrocarbons and soot. Measurements were made on the centerline of gas temperature with thermocouples, of soot volume fraction with laser-induced incandescence, and of major species and C1 to C13 hydrocarbon concentrations with online mass spectrometry. The maximum centerline soot volume fraction in the flames decreased strongly and monotonically as air was added to the fuel, with a reduction of one half from the non-premixed flame to a flame with a primary equivalence ratio of 15. This observation shows that even the small amounts of fuel-side air produced by ‘accidental’ mechanisms such as entrainment at the flame base can significantly impact soot concentrations. The hydrocarbon measurements showed that premixing caused a greater amount of benzene in the pyrolysis zone to be consumed through phenoxy formation, such that the concentrations of the phenoxy decomposition product cyclopentadienyl increased, whereas the concentrations of substituted benzenes such as phenylacetylene and toluene decreased. The naphthalene concentrations also decreased monotonically, which indicates that most of the naphthalene was formed from phenylacetylene by the HACA mechanism (or from benzyl by propargyl addition), and that negligible amounts of naphthalene were formed from cyclopentadienyl.
A preliminary study of the application of Background Oriented Schlieren (BOS) for the qualitative imaging of methane emissions from coal

Methane presents a pervasive risk in most coal mines, its dilution being one of the primary objectives of the ventilation system. Although many different types of detectors and techniques exist for quantifying methane, little is known about the qualitative aspects of methane, such as visualising how this gas flows from coal. Background Oriented Schlieren (BOS) provides a potential method from qualitative analysis of methane emissions. BOS is an imaging technique designed to visualise normally invisible flows in transparent media. This paper is a preliminary investigation of the feasibility of using the BOS technique for imaging methane release from coal.
Carbon ion charge states and energy distributions for DLC ablation plumes from 100-fs 780 nm laser pulses

Abstract A time-of-flight, sector-field, electrostatic analyzer has been used to obtain detailed information about the ionic charge states of carbon and their associated energy distributions for laser ablation plumes typical of those used for depositing diamond-like carbon (DLC) films. It is observed that for 100 fs laser pulses in the 10 14 to 10 16 W/cm 2 intensity range, the characteristics of these distributions are highly dependent on the peak-to-background contrast ratio of the laser pulse. Ion energies are observed and examined in the kinetic energy range from 100 eV to 20 keV. Energy distributions are compared with numerical results for hydrodynamic expansion and for effects of plasma ambipolar layers.
On the Cognition in Cognitive Development.

Abstract I argue that Demetriou and Raftopoulos have presented a complex and thought-provoking model of cognitive developmental change, but one that is based on a false and misleading assumption about the nature of representation. This assumption—roughly, that representation is encoding—cannot work and has induced serious problems in the model. An alternative model of representation is outlined, in part for contrast and in part to demonstrate that the aporia of encodingist assumptions can be avoided. The encodingist assumption about representation, however, is one that Demetriou and Raftopoulos share with the majority of psychologists, developmentalists included, so the stakes here are not limited to this model alone.
Business Ethics Training: Face-to-face and at a Distance

An 11-week hybrid distance learning/personal contact ethics training program, customized for a leading information technology firm, is described in the format of a sequential process. The process is grounded on discourse ethics and the ethics training guidelines premised by the Hastings Institute. Indications from the firm and from the program’s participants are that the training has been beneficial.
Carbon monoxide methanation over nickel/alumina thin-film model catalysts

Abstract A new method for model surface preparation of nickel/alumina catalysts, compatable with an ultrahigh vacuum environment, is described. The model system consists of a tungsten substrate, an evaporated aluminum film which is subsequently oxidized, and an evaporated, submonolayer coverage of nickel. This thin-film model has been used to study carbon monoxide methanation. The specific reaction rates and activation energy associated with this reaction compare favorably with the corresponding values found for high-area, supported nickel catalysts. Advantages and possible applications of the model system are discussed.
Acid saline fluid inclusions: examples from modern and Permian extreme lake systems

Some of the Earth’s most extreme aqueous chemistries are found at acid saline lakes and associated shallow groundwaters. Modern lakes and groundwaters in Western Australia have pHs as low as 1.5, total dissolved solids as high as 32%, unusually high concentrations of Al, Si, Fe, As, and Sb, and many other chemical characteristics atypical of natural waters. Analogous Permian red bed and evaporite lake deposits in the US midcontinent also had extreme water compositions, including negative pH. Fluid inclusions in chemical sediments from modern and Permian acid saline lakes record specific physical, chemical, and biological conditions. Primary inclusions in this bedded halite and gypsum are trapped shallow lake water, air bubbles, crystals of other minerals, and microorganisms and organic compounds. Isolated fluid inclusions in early diagenetic phases of halite are remnants of shallow groundwaters and can be analyzed to determine chemical compositions of past groundwaters. A variety of traditional methods, including petrography, freezing–melting microthermometry and laser Raman spectroscopy, and innovative variations, such as homogenization of artificially nucleated vapor bubbles and UV-vis petrography, produce data detailing environmental conditions. Other traditionally used methods, such as laser ablation ICPMS, are not effective due to the inclusions’ high and complex salinity, extremely low pH and/or low pressure. Making synthetic solutions that match the complexity of natural acid saline inclusions is another challenge. Fluid inclusions in acid-precipitated halite have proven to be excellent repositories for past surface chemical, physical, and biological conditions. Although the methods used and data obtained from acid-precipitated halite and gypsum are not exactly the same as for neutral-alkaline evaporites, acid inclusions provide high-resolution environmental data for modern and ancient extreme environments. These extreme fluids may also have similarities to other past extreme environments, to ore mineralizing fluids, and to past liquids on Mars.
Current outcomes and risk factors for the Norwood procedure.

Objective Tremendous strides have been made in the outcomes for hypoplastic left heart syndrome and other functional single-ventricle malformations over the past 25 years. This progress relates primarily to improvements in survival for patients undergoing the Norwood procedure. Previous reports on risk factors have been on smaller groups of patients or collected over relatively long periods of time, during which management has evolved. We analyzed our current results for the Norwood procedure with attention to risk factors for poor outcome. Methods A single-institution review of all patients undergoing a Norwood procedure for a single-ventricle malformation from May 1, 2001, through April 30, 2003, was performed. Patient demographics, anatomy, clinical condition, associated anomalies, operative details, and outcomes were recorded. Results Of the 111 patients, there were 23 (21%) hospital deaths. Univariate analysis revealed noncardiac abnormalities (genetic or significant extracardiac diagnosis, P = .0018), gestational age ( P = .03), diagnosis of unbalanced atrioventricular septal defect ( P = .017), and weight of less than 2.5 kg ( P = .0072) to be related to hospital death. On multivariate analysis, only weight of less than 2.5 kg and noncardiac abnormalities were found to be independent risk factors. Patients with either of these characteristics had a hospital survival of 52% (12/23), whereas those at standard risk had a survival of 86% (76/88). Conclusions Although improvements in management might have lessened the effect of some of the traditionally reported risk factors related to variations in the cardiovascular anatomy, noncardiac abnormalities and low birth weight remain as a future challenge for the physician caring for the patient with single-ventricle physiology.
Utilizing the IEEE 802.16 standard for homeland security applications

The authors are developing a flexible sensor network with numerous potential uses. This paper presents one constructive application of the sensor integration platform and network. The theory of operation is as follows. Multiple sensing/processing nodes are scattered about a 30-­mile radius on land. Each node has the capability to handle up to a few different sensors based on user needs. The nodes operate autonomously while continuously acquiring data and process the information locally. The information deemed relevant to the system operator is uplinked to a base station at optimal intervals. Further data collection takes place at the base station where an operator can take appropriate action. Communication between the base station and nodes is based upon the emerging IEEE 802.16 standard. This enables broadband level information transfer at ranges capable of covering entire metropolitan areas. The application discussed in this paper is a homeland security monitoring system. This system would make use of a variety of nodes to collect data from surveillance cameras at border crossings and high value assets, water contamination sensors, weather sensors, and other sensors the user sees necessary. A technical description of the system architecture, its benefits, and limitations will be included. The utility of the 802.16 standard will also be incorporated in the paper.
DNA adducts as exposure biomarkers and indicators of cancer risk.

Quantitation of DNA adducts in human tissues has been achieved with highly sensitive techniques based on adduct radiolabeling, antisera specific for DNA adducts or modified DNA, and/or adduct structural characterization using chemical instrumentation. Combinations of these approaches now promise to elucidate specific adduct structures and provide detection limits in the range of 1 adduct/10(9) nucleotides. Documentation of human exposure and biologically effective dose (i.e., chemical bound to DNA) has been achieved for a wide variety of chemical carcinogens, including polycyclic aromatic hydrocarbons (PAHs), aromatic amines, heterocyclic amines, aflatoxins, nitrosamines, cancer chemotherapeutic agents, styrene, and malondialdehyde. Due to difficulties in exposure documentation, dosimetry has not been precise with most environmental and occupational exposures, even though increases in human blood cell DNA adduct levels may correlate approximately with dose. Perhaps more significant are observations that lowering exposure results in decreasing DNA adduct levels. DNA adduct dosimetry for environmental agents has been achieved with dietary contaminants. For example, blood cell polycyclic aromatic hydrocarbon-DNA adduct levels were shown to correlate with frequency of charbroiled meat consumption in California firefighters. In addition, in China urinary excretion of the aflatoxin B1-N7-guanine (AFB1-N7-G) adduct was shown to increase linearly with the aflatoxin content of ingested food. Assessment of DNA adduct formation as an indicator of human cancer risk requires a prospective nested case-control study design. This has been achieved in one investigation of hepatocellular carcinoma and urinary aflatoxin adducts using subjects followed by a Shanghai liver cancer registry. Individuals who excreted the AFB1-N7-G adduct had a 9.1-fold adjusted increased relative risk of hepatocellular carcinoma compared to individuals with no adducts. Future advances in this field will be dependent on chemical characterization of specific DNA adducts formed in human tissues, more-precise molecular dosimetry, efforts to correlate DNA adducts with cancer risk, and elucidation of opportunities to reduce human DNA adduct levels.
An Attempted Clarification of the Psychological Distance Construct

Summary In order to determine whether Kuethe's social schemata technique reflects more the actual or desired patterns of social transactions, 107 Ss were administered two versions of this schematic space method and several measures of social preference. They were also observed in actual verbal and nonverbal social transactions in a number of situations. Males' free-placements were related to overt physical social responses; their replacements corresponded to social needs. Females' free-placements reflected social needs.
Cross-Layer Self-Adaptive/Self-Aware System Software for Exascale Systems

The extreme level of parallelism coupled with the limited available power budget expected in the exascale era brings unprecedented challenges that demand optimization of performance, power and resiliency in unison. Scalability on such systems is of paramount importance, while power and reliability issues may change the execution environment in which a parallel application runs. To solve these challenges exascale systems will require an introspective system software that combines system and application observations across all system stack layers with online feedback and adaptation mechanisms. In this paper we propose the design of a novel self-aware, selfadaptive system software in which a kernel-level Monitor, which continuously inspects the evolution of the target system through observation of Sensors, is combined with a user-level Controller, which reacts to changes in the execution environment, explores opportunities to increase performance, save power and adapts applications to new execution scenarios. We show that the monitoring system accurately monitors the evolution of parallel applications with a runtime overhead below 1-2%. As a test case, we design and implement a runtime system that aims at optimizing application's performance and system power consumption on complex hierarchical architectures. Our results show that our adaptive system reaches 98% of performance efficiency of manually-tuned applications.
Group properties of a one-dimensional system of equations for wave propagation in various media

Abstract The group properties and Lie algebra are derived for a one-dimensional system of equations that model wave propagation in various media including viscoelastic and viscoplastic materials. The differential constitutive relation in this model contains an arbitrary function which affects the group structure. The restrictions of the group analysis imposed on the form of this constitutive law are described. Special attention is given to a quasi-linear differential form that models materials exhibiting a rate effect. In addition, the actions of specific one-parameter sub-groups of the full Lie group on this system of equations are discussed.
Relative merits of mri, transrectal endosonography and ct in diagnosis and staging of carcinoma of prostate

Abstract Magnetic resonance imaging (MRI) and transrectal sonography of 27 patients with biopsy-proved carcinoma of the prostate were performed to compare the sensitivity of these modalities each other for diagnosis and to computed tomography (CT) for staging. Sonography was superior to MRI for the detection of intraglandular carcinoma and capsular disruption. MRI was superior to both sonography and CT for evaluating seminal vesicle invasion, and slightly better than CT for detecting lymphadenopathy.
Visual homing with a pan-tilt based stereo camera

Visual homing is a navigation method based on comparing a stored image of the goal location and the current image (current view) to determine how to navigate to the goal location. It is theorized that insects, such as ants and bees, employ visual homing methods to return to their nest. Visual homing has been applied to autonomous robot platforms using two main approaches: holistic and feature-based. Both methods aim at determining distance and direction to the goal location. Navigational algorithms using Scale Invariant Feature Transforms (SIFT) have gained great popularity in the recent years due to the robustness of the feature operator. Churchill and Vardy have developed a visual homing method using scale change information (Homing in Scale Space, HiSS) from SIFT. HiSS uses SIFT feature scale change information to determine distance between the robot and the goal location. Since the scale component is discrete with a small range of values, the result is a rough measurement with limited accuracy. We have developed a method that uses stereo data, resulting in better homing performance. Our approach utilizes a pan-tilt based stereo camera, which is used to build composite wide-field images. We use the wide-field images combined with stereo-data obtained from the stereo camera to extend the keypoint vector described in to include a new parameter, depth (z). Using this info, our algorithm determines the distance and orientation from the robot to the goal location. We compare our method with HiSS in a set of indoor trials using a Pioneer 3-AT robot equipped with a BumbleBee2 stereo camera. We evaluate the performance of both methods using a set of performance measures described in this paper.
Policy-making by different means: The chief justice's attempts to shape policy through the judicial conference of the United States

Formal theories of majority voting suggest that the organizing rules of the Judicial Conference of the United States (JCUS) present the Chief Justice of the Supreme Court with the opportunity to sway the policy statements of the JCUS in favor of his preferred language. Existing political science literature on the Chief Justice demonstrates that Chiefs use their authority to pursue their policy agendas in a variety of other settings. The membership of the JCUS Executive Committee - a particularly important committee in the Conference - is examined over the 1970-98 period. Both Chiefs during this period consistently stacked the committee with conservative policy outliers, and did so in a sophisticated strategic fashion.
Assembly of mesoscale particles over large areas and its application in fabricating tunable optical filters

This paper describes a method for the crystallization of mesoscale particles over areas as large as ∼1 cm2. We injected an aqueous dispersion of spherical particles into a cell formed by two glass substrates and a square frame of photoresist that had been patterned on the surface of one of the substrates. One side of the frame had channels on its surface that could retain the particles while letting the solvent flow through. External gas pressure and sonication drove the particles into a cubic-close-packed (ccp) assembly with the (111) face parallel to the surfaces of the glass substrates. The smallest particles that have been crystallized by this method are polystyrene beads of ∼60 nm in diameter. The procedure presented here offers a number of attractive features: (i) It is relatively fast. For example, polystyrene beads of 0.48 μm in diameter can be crystallized into a 25 layer assembly over an area of ∼1 cm2 in ∼48 h. (ii) It has a tight control over the surface morphology and the number of layers of...
Incidence of apoptosis in parthenogenetic porcine embryos generated by using protein kinase or protein synthesis inhibitors.

Abstract In mammals, embryonic development can be artificially initiated by activating the oocyte using a number of methods. In the present research, we investigated whether butyrolactone I and cycloheximide, two chemicals frequently used in combined oocyte activation protocols, have any detrimental effect on programmed cell death in the developing porcine embryo. Parthenogenetic porcine blastocysts were generated by the following methods: (1) electroporation followed by blocking the activity of specific protein kinases with butyrolactone I; (2) electroporation followed by inhibition of protein synthesis using cycloheximide; and (3) electroporation only (control). The viability of the embryos was evaluated by monitoring the frequency of cells with early and late signs of programmed cell death. There was no difference between the embryos in terms of blastocyst formation (ranging from 27.5 ± 3.8 and 33.3 ± 3.5%) and total nuclear number (ranging from 23.5 ± 1.1 and 31.8 ± 4.4). In addition, the occurrence of apoptosis was also similar in the three experimental groups. The proportion of cells with active caspase-9 (a sign of early apoptosis) in the blastocysts produced by the different activation methods was between 19.4 ± 1.9 and 23.0 ± 2.4%. The annexin V assay revealed that phosphatidylserine flip (another early apoptotic event) took place in 24.4 ± 2.1 to 32.3 ± 2.4% of the blastomeres. Finally DNA fragmentation, a sign of late stage apoptosis determined by the TUNEL assay, occurred in 8.5 ± 2.4 to 10.1 ± 3.0% of the cells. The results indicate that temporary inhibition of specific protein kinases or protein synthesis does not increase the onset of apoptosis in parthenogenetic porcine blastocysts.
Efficient synthesis methodology for optimal inverter-based transimpedance amplifiers

In this paper, we present a new synthesis methodology that facilitates the design automation of maximum bandwidth transimpedance amplifier (TIA) for optical communications under the constraint of a specific bit error rate. Our synthesis methodology is based on newly developed models that characterize the input referred noise and bandwidth. Our technique provides the optimal parameters of the transimpedance amplifier for maximizing the bandwidth. These optimal parameters are mapped to equivalent circuit parameters to achieve the optimal sizing of the TIA. Our methodology is characterized by its very fast design convergence as well as better results compared to conventional design techniques. We applied our synthesis methodology in designing a TIA for optical interconnect systems using the 0.25?m and 0.18?m CMOS technologies.
Therapeutic Boundaries or Barriers: Thoughts on Emotional Distance in Psychiatric Mental-Health Nursing

Edited byMona M. Shattell, RN, PhD, FAANDePaul University, School of Nursing, Chicago, Illinois, USAEdited byMichelle Cleary, RN, PhDSchool of Nursing and Midwifery, University of Western Sydney, A...
Superparamagnetic Au-Fe 3 O 4 Nanoparticles: One-Pot Synthesis, Biofunctionalization and Toxicity Evaluation

Superparamagnetic Au-Fe3O4 bifunctional nanoparticles have been synthesized using a single step hot-injection precipitation method. The synthesis involved using Fe(CO)5 as iron precursor and HAuCl4 as gold precursor in the presence of oleylamine and oleic acid. Oleylamine helps in reducing Au3+ to Au0 seeds which simultaneously oxidizes Fe(0) to form Au-Fe3O4 bifunctional nanoparticles. Triton? X-100 was employed as a highly viscous solvent to prevent agglomeration of Fe3O4 nanoparticles. Detailed characterization of these nanoparticles was performed by using x-ray powder diffraction, transmission electron microscopy, scanning tunneling electron microscopy, UV-visible spectroscopy, M?ssbauer and magnetometry studies. To evaluate these nanoparticles? applicability in biomedical applications, L-cysteine was attached to the Au-Fe3O4 nanoparticles and cytotoxicity of Au-Fe3O4 nanoparticles was tested using CHO cells by employing MTS assay. L-cysteine modified Au-Fe3O4 nanoparticles were qualitatively characterized using Fourier transform infrared spectroscopy and Raman spectroscopy; and quantitatively using acid ninhydrin assay. Investigations reveal that that this approach yields Au-Fe3O4 bifunctional nanoparticles with an average particle size of 80 nm. M?ssbauer studies indicated the presence of Fe in Fe3+ in A and B sites (tetrahedral and octahedral, respectively) and Fe2+ in B sites (octahedral). Magnetic measurements also indicated that these nanoparticles were superparamagnetic in nature due to Fe3O4 region. The saturation magnetization for the bifunctional nanoparticles was observed to be ?74 emu g?1, which is significantly higher than the previously reported Fe3O4 nanoparticles. M?ssbauer studies indicated that there was no significant Fe(0) impurity that could be responsible for the superparamagnetic nature of these nanoparticles. None of the investigations showed any presence of other impurities such as Fe2O3 and FeOOH. These Au-Fe3O4 bifunctional nanoparticles showed no significant cytotoxicity to the CHO cells up to 48 h even at concentrations of 1 mg ml?1 making them suitable for biomedical applications such as local heat generators (hyperthermia) for cancer treatment and drug delivery vehicles.
The Lack of Favorable Responses of an Endangered Pitcher Plant to Habitat Restoration

Restoring habitat structure that existed before active and inadvertent fire suppression is thought to be critical to maintaining populations of some rare plants in fire-suppressed habitats. Nevertheless, the impacts of habitat restoration on most endangered plants are poorly understood. Current theory predicts and empirical studies have shown that the reduction of shade or competition (frequently a goal of many habitat restoration projects in degraded fire-dependent ecosystems) benefits plants adapted to nutrient-poor soils by increasing the benefit-to-cost ratio of adaptations for enhanced nutrient capture. Here, I examined how experimental reduction of neighboring plants in a wet longleaf pine community dominated in the ground cover by shrubs and stump sprouts influenced the growth, the reproduction, the carnivorous effort, and the benefits of carnivory in a U.S. federally endangered species, Sarracenia rubra ssp. alabamensis. Two years of data showed no significant effects of neighbor reduction or prey exclusion on any of several indicators of plant performance, nor was there any evidence of a hypothesized morphological trade-off between shade avoidance and prey capture. These results were unexpected. Inadequate replication and atypical precipitation patterns were ruled out as possible explanations. The population studied here (unlike that of a different, but morphologically similar, species growing in a fire-maintained pine grass–sedge savanna) did not exhibit the ability to respond to variation in competition from neighboring plants.
Do Frontal Cyclones Change Size? Observed Widths of North Pacific Lows

Abstract Wavelet transforms in the longitudinal and latitudinal directions are applied to sea level pressure data for 12 extratropical cyclones. Each low is tracked over time from a stage of small amplitude to a stage of large amplitude. The wavelet transform provides a quantitative, localized estimate of the size of the low pressure. Separate one-dimensional transforms are taken in the longitudinal and latitudinal directions; these are averaged to reduce scale variations created as circular asymmetries rotate around a low center. On average, the size of the lows increases such that the diameter doubles over a 4-day period. These results pass a standard “f test” with greater than 99% confidence. Some implications for theoretical studies are included.
Combined forced and free convective diffusion in vertical semipermeable parallel plate ducts

The effect of natural convection on polarization and flow patterns in liquid phase convective diffusion in a vertical duct with semipermeable membrane walls has been investigated theoretically. It is found that at low flow rates, gravitational fields can play a significant role in distorting the velocity profiles and thereby they affect the transition from laminar to turbulent flow. Natural convection also significantly affects mass transfer rates and therefore the extent of polarization at low flow rates. Results are presented for both momentum and mass transfer in upward and downward flows for different wall Peclet numbers. The hydrodynamic stability of the system also has been investigated and critical values of the buoyancy parameters are reported. Also, these results enable one to estimate when natural convection may create errors in membrane testing systems. The analysis and results are of practical interest in reverse osmosis and other membrane separation processes. The more productive the system, the more likely it will be that buoyancy effects are important.
Pericaval and periannular intra-atrial reentrant tachycardias in patients with congenital heart disease.

Pericaval IART in CHD. Introduction: Intra-atrial reentrant tachycardia (IART) is a frequent late sequel of congenital heart surgery, often involving the cavotricuspid isthmus. In this report, we characterize pericaval reentry, a novel mechanism of isthmus-dependent IART in congenital heart patients, and compare its electrophysiologic characteristics with periannular atrial flutter. Methods and Results: Electrophysiologic and electroanatomic mapping data and acute outcomes were reviewed in postoperative patients with congenital heart disease who underwent electrophysiologic study/radiofrequency catheter ablation at The Children's Hospital, Boston between January 1999 and November 2000. The study included all congenital heart patients with IART and who had undergone (1) the Fontan procedure and (2) a biventricular surgical repair other than atrial switch procedures. Thirty-seven IARTs were mapped in 22 Fontan patients. Twelve of 37 IARTs (33%) that revolved about the inferior vena cava (IVC) and involved the isthmus between the IVC and the tricuspid dimple/right-sided AV valve were identified in 12 patients (48%). Mean pericaval IART cycle length was 332 ± 60 msec (range 240–410). An adjacent or surrounding area of scarring was observed in 10 of 12 IARTs. Slow zones (mean activation latency 39%± 11% IART cycle length) were detected in 8 of 12 circuits. The boundaries of the zone of slow conduction were scar-low crista (6) and scar-IVC (2). Periannular IART with CL 289 ± 65 ms was observed in 14 of 20 patients with 4-chambered hearts. Slow zones (mean activation latency 28 ± 9% IART cycle length) were found in 8 of 14 circuits. In both forms of IART, the predominant direction of activation of the isthmus was lateral to septal; 83% in pericaval IART and 87% in periannular IART. Radiofrequency catheter ablation successfully terminated 11 of 11 pericaval and 13 of 14 periannular IARTs. Conclusion: Pericaval reentry is a novel and ablatable mechanism of IART in patients specific to the Fontan procedure. It is distinguished from periannular atrial reentry by its association with Fontan anatomy, longer cycle lengths, and occurrence of a prominent discrete zone(s) of slow conduction. Both pericaval and periannular reentry show a marked preference for utilization of the isthmus in a lateral-to-septal direction. (J Cardiovasc Electrophysiol, Vol. 14, pp. 119-125, February 2003)
Denitrification from nitrogen-fixing biologically crusted soils in a cool desert environment, southeast Utah, USA

Nitrogen fixation by microorganisms within biological soil crust (“biocrust”) communities provides an important pathway for N inputs in cool desert environments where soil nutrients are low and symbiotic N-fixing plants may be rare. Estimates of N fixation in biocrusts often greatly exceed that of N accretion rates leading to uncertainty regarding N loss pathways. In this study we examined nitrogen fixation and denitrification rates in biocrust communities that differed in N fixation potential (low N fixation = light cyanobacterial biocrust, high N fixation = dark cyanolichen crust) at four temperature levels (10, 20, 30, 40°C) and four simulated rainfall levels (0.05, 0.2, 0.6, 1 cm rain events) under controlled laboratory conditions. Acetylene reduction rates (AR, an index of N fixation activity) were over six-fold higher in dark crusts relative to light crusts. Dark biocrusts also exhibited eight-fold higher denitrification rates. There was no consistent effect of temperature on denitrification rates, but there was an interactive effect of water addition and crust type. In light crusts, denitrification rates increased with increasing water addition, whereas the highest denitrification rates in dark crusts were observed at the lowest level of water addition. These results suggest that there are no clear and consistent environmental controls on short-term denitrification rates in these biologically crusted soils. Taken together, estimates of denitrification from light and dark biocrusts constituted 3 and 4% of N fixation rates, respectively suggesting that losses as denitrification are not significant relative to N inputs via fixation. This estimate is based on a previously published conversion ratio of ethylene produced to N fixed that is low (0.295), resulting in high estimates of N fixation. If future N fixation studies in biologically crusted soils show that these ratios are closer to the theoretical 3:1 ratio, denitrification may constitute a more significant loss pathway relative to N fixed.
Relationships between Climate Parameters and Forest Vegetation At and Near Digya National Park, Ghana

This paper evaluates the effect of three climate parameters on forest cover in Ghana and the normalized difference vegetation index (NDVI) at Digya National Park derived from Landsat image data. Climate data (temperature, humidity, dewpoint, rainfall) are assembled from statistics provided by Ghana's Meteorological Agency. The study introduces a weighted averaging method by computing weather information from neighbouring stations. Also, this research introduces a model of dewpoints, enabling the direct calculation of dewpoints from temperature and humidity data. The major finding is that while temperature significantly affects forest cover and Park vegetation, dew-points and rainfall do not. The paper suggests where future research may be more fruitful in analyzing the effects of climate on vegetation.
A Paradigm for Practice

Lack of consensus on a paradigm for practice inhibits the cumulative development of practical knowledge and skills. It also encourages devolution of these and other paradigm functions by default to the established paradigm in the policy movement, reductionism, which includes positive methodology. But reductionism is insufficient for practice. It tends to displace practical aims and expectations, and discount and delegitimize practical and other ways of knowing. This gives rise to problems in practice, illustrated here by problems in psychotherapy, global climate change, and various ‘high-modern’ schemes to improve the human condition. To help alleviate such problems eventually, this article outlines a contextual paradigm for practice based on examples of good practice, the policy sciences, and related sources. The immediate purpose is to stimulate policy scientists, other practitioners, and other contextualists to make explicit and compare their paradigms.
Potent protection against aflatoxin-induced tumorigenesis through induction of Nrf2-regulated pathways by the triterpenoid 1-[2-cyano-3-,12-dioxooleana-1, 9(11)-dien-28-oyl]imidazole

Synthetic triterpenoid analogues of oleanolic acid are potent inducers of the phase 2 response as well as inhibitors of inflammation. We show that the triterpenoid, 1-[2-cyano-3-,12-dioxooleana-1,9(11)-dien-28-oyl]imidazole (CDDO-Im), is a highly potent chemopreventive agent that inhibits aflatoxin-induced tumorigenesis in rat liver. The chemopreventive potency of CDDO-Im was evaluated by measuring inhibition of formation of putative preneoplastic lesions (glutathione S-transferase P positive foci) in the liver of rats exposed to aflatoxin B1. CDDO-Im produces an 85% reduction in the hepatic focal burden of preneoplastic lesions at 1 micromol/kg body weight and a >99% reduction at 100 micromol/kg body weight. CDDO-Im treatment reduces levels of aflatoxin-DNA adducts by approximately 40% to 90% over the range of 1 to 100 micromol/kg body weight. Additionally, changes in mRNA levels of genes involved in aflatoxin metabolism were measured in rat liver following a single dose of CDDO-Im. GSTA2, GSTA5, AFAR, and EPHX1 transcripts are elevated 6 hours following a 1 micromol/kg body weight dose of CDDO-Im. Microarray analysis using wild-type and Nrf2 knockout mice confirms that many phase 2 and antioxidant genes are induced in an Nrf2-dependent manner in mouse liver following treatment with CDDO-Im. Thus, low-micromole doses of CDDO-Im induce cytoprotective genes, inhibit DNA adduct formation, and dramatically block hepatic tumorigenesis. As a point of reference, oltipraz, an established modulator of aflatoxin metabolism in humans, is 100-fold weaker than CDDO-Im in this rat antitumorigenesis model. The unparalleled potency of CDDO-Im in vivo highlights the chemopreventive promise of targeting Nrf2 pathways with triterpenoids.
Face emotion labeling deficits in children with bipolar disorder and severe mood dysregulation

Children with narrow phenotype bipolar disorder (NP-BD; i.e., history of at least one hypomanic or manic episode with euphoric mood) are deficient when labeling face emotions. It is unknown if this deficit is specific to particular emotions, or if it extends to children with severe mood dysregulation (SMD; i.e., chronic irritability and hyperarousal without episodes of mania). Thirty-nine NP-BD, 31 SMD, and 36 control subjects completed the emotional expression multimorph task, which presents gradations of facial emotions from 100% neutrality to 100% emotional expression (happiness, surprise, fear, sadness, anger, and disgust). Groups were compared in terms of intensity of emotion required before identification occurred and accuracy. Both NP-BD and SMD youth required significantly more morphs than controls to label correctly disgusted, surprised, fearful, and happy faces. Impaired face labeling correlated with deficient social reciprocity skills in NP-BD youth and dysfunctional family relationships in SMD youth. Compared to controls, patients with NP-BD or SMD require significantly more intense facial emotion before they are able to label the emotion correctly. These deficits are associated with psychosocial impairments. Understanding the neural circuitry associated with face-labeling deficits has the potential to clarify the pathophysiology of these disorders.
Needle insertion and radioactive seed implantation in human tissues: simulation and sensitivity analysis

To facilitate training and planning for medical procedures such as prostate brachytherapy, we are developing an interactive simulation of needle insertion and radioactive seed implantation in soft tissues. We describe a new 2D dynamic FEM model based on a reduced set of scalar parameters such as needle friction, sharpness, and velocity, where the mesh is updated to maintain element boundaries along the needle shaft and the effects of needle tip and frictional forces are simulated. The computational complexity of our model grows linearly with the number of elements in the mesh and achieves 24 frames per second for 1250 triangular elements on a 750 MHz PC. We use the simulator to characterize the sensitivity of seed placement error to physician-controlled and biological parameters. Results indicate that seed placement error is highly sensitive to physician-controlled parameters such as needle position, sharpness, and friction, and less sensitive to patient-specific parameters such as tissue stiffness and compressibility.
Temporal structure coding with and without awareness

In order to interpret a constantly changing environment, visual events far apart in space and time must be integrated into a unified percept. While spatial properties of invisible signals are known to be encoded without awareness, the fate of temporal properties remains largely unknown. Here, we probed temporal integration for two distinct motion stimuli that were either visible or rendered invisible using continuous flash suppression. We found that when invisible, both the direction of apparent motion and the gender of point-light walkers were processed only when defined across short time periods (i.e., respectively 100 ms and 1000 ms). This limitation was not observed under full visibility. These similar findings at two different hierarchical levels of processing suggest that temporal integration windows shrink in the absence of perceptual awareness. We discuss this phenomenon as a key prediction of the global neuronal workspace and the information integration theories of consciousness.