cssi/SciSciGPT-SciSciNet huggingface dataset:
Electric source localization of the auditory P300 agrees with magnetic source localization

Abstract The event-related cortical potential elicited in the context of auditory target detection tasks includes the N1, P2 and P3 components. The aim of the present study was to identify the sources of these scalp-recorded components using an electrical multiple dipole model. Nine healthy adults volunteered for the study. An auditory oddball paradigm was used. Stimuli (18% target and 82% non-target tones) were delivered through ear-phones and subjects were required to silently count the targets. Event-related potentials (ERPs) to these stimuli were recorded by 30 electrodes placed on the scalp. The identification of the sources of the ERP was attempted using the brain electric source analysis (BESA) program. The instantaneous source locations of N1, P2 and P3 reported in magnetoencephalographic (MEG) literature were used as initial starting locations for the spatio-temporal multiple dipole modeling of the EEG data. First the auditory long latency responses were modeled separately. Bilateral superior temporal plane sources with almost vertical orientations explained the first 250 msec window of the non-target tone recording including N l P 2 complex. This agrees with MEG source localization of N 1 m P 2 m . Two slightly deeper dipoles in superior temporal gyri and bilateral dipoles in hippocampi or parahippocampal areas explained P3 (analysis window 250–600 msec). The final model explained the complete epoch of 600 msec with 6 dipoles and the residual variances of individual models ranged from 3.83% to 7.77%. The concordance between MEG and BESA source localization results supports the notion of generators in temporal lobes for the N l P 2 complex and generators in temporal and hippocampal areas for the P3 component.
Immunohistochemical localization of gonadotropin-releasing hormone (GnRH) in the brain and infundibulum of the sheep

The distribution of gonadotropin-releasing hormone (GnRH) was studied in the brain and infundibulum (INF) or median eminence of sheep utilizing a peroxidase-antiperoxidase immunohistochemical method. This procedure utilized a specific antiserum generated against GnRH conjugated to bovine serum albumin. In the rostral INF, the greatest concentration of GnRH positive axons was found in the medial region, mostly in the external layer dorsal to the hypophysial portal plexus. In the intermediate portion of the INF, the hormone was mainly observed in the external layer at the more dorsolateral areas ventral to the tuberoinfundibular sulcus. GnRH was generally located medially in the caudal portion of the INF and dorsomedially in the rostral infundibular stalk. Substantial amounts of reaction product were also noted in the internal layer throughout the entire rostrocaudal extent of the INF. The hormone was localized in axons throughout the brain from the septal and medial preoptic areas to the mammillary bodies. GnRH-positive perikarya were scattered in various regions of the infundibular (arcuate) and for the first time in the ventromedial nuclei of sheep hypothalamus.
Channelopathies and dendritic dysfunction in fragile X syndrome

Dendritic spine abnormalities and the metabotropic glutamate receptor theory put the focus squarely on synapses and protein synthesis as the cellular locus of fragile X syndrome. Synapses however, are only partly responsible for information processing in neuronal networks. Neurotransmitter triggered excitatory postsynaptic potentials (EPSPs) are shaped and integrated by dendritic voltage-gated ion channels. These EPSPs, and in some cases the resultant dendritic spikes, are further modified by dendritic voltage-gated ion channels as they propagate to the soma. If the resultant somatic depolarization is large enough, action potential(s) will be triggered and propagate both orthodromically down the axon, where it may trigger neurotransmitter release, and antidromically back into the dendritic tree, where it can activate and modify dendritic voltage-gated and receptor activated ion channels. Several channelopathies, both soma-dendritic (L-type calcium channels, Slack potassium channels, h-channels, A-type potassium channels) and axo-somatic (BK channels and delayed rectifier potassium channels) were identified in the fmr1-/y mouse model of fragile X syndrome. Pathological function of these channels will strongly influence the excitability of individual neurons as well as overall network function. In this chapter we discuss the role of voltage-gated ion channels in neuronal processing and describe how identified channelopathies in models of fragile X syndrome may play a role in dendritic pathophysiology.
What Do Fifth Graders Read

What do fifth graders read? This reading interest inventory was based on lists of books that 1079 Iowa fifth graders read for pleasure during the five-year period from 1978-1983. More girls (589) than boys (490) participated in the voluntary program and read more books (two more per year). A sample group of 100 boys and 100 girls was analyzed. Sex differentiation was apparent in the analysis. Fiction was the most frequently selected genre by both sexes. Realistic fiction was chosen twice as often as fantasy. Girls selected fiction in much greater numbers than boys, but nonfiction was selected much more frequently by the boys. The other genre were chosen in greatly reduced numbers and were not significantly sex-differentiated. The most popular titles and authors were identified and differences in theme choices were noted. Such information can aid the adult in selecting appropriate reading materials to stimulate the desire to read.
An Initial Examination of Religious Coping in Children With Asthma

This study evaluated the relations between positive religious coping (PRC) and negative religious coping (NRC) strategies and adjustment in 87 children and adolescents (described as “children”) hospitalized for asthma. Children's adjustment during hospitalization and at follow-up was correlated with and regressed onto measures of PRC and NRC. After controlling for relevant variables, religious coping predicted up to 50% of the variance in adjustment measures. Religious coping also significantly predicted adjustment after controlling for established measures of secular coping. PRC did not predict adjustment as hypothesized, other than predicting spiritual growth. NRC predicted poorer adjustment during hospitalization and at follow-up, and an increase in anxiety over time suggesting potential risk to children's adjustment. Although methodological limitations are noted, these initial findings provide a foundation on which to further examine the palliative and potentially harmful effects of children's religio...
High Resolution AMLCD made with a‐Si:H TFTs and with an Al‐Gate and IZO Last Structure

Using a low-cost a-Si:H-TFT process with an Al gate and IZO last structure a direct-view active matrix display with the highest information content has been fabricated in a phase-2 mass production line in DTI Himeji. The display, a 16.3″ diagonal 200ppi-QSXGA (Quad SXGA) incorporates 7680 columns and 2048 rows. Each subpixel measures 42μm(h)x126μm(v).
Public Awareness of Congressional Representatives Recall Versus Recognition

The ability of the mass public to recall the name of the incumbent congressional repre sentative is compared to the ability to recognize their congressman's name. Name recog nition is substantially...
The Range and Validity of the Field Current Equation

Field currents from cold cathodes under high vacuum conditions were investigated over a range from ${10}^{\ensuremath{-}17}$ to ${10}^{\ensuremath{-}5}$ ampere. Electrometer measurements of currents below ${10}^{\ensuremath{-}10}$ ampere showed no deviation from the empirical equation of Millikan and Lauritsen. Precise measurements in the higher range exhibited a consistent deviation from the Millikan and Lauritsen equation, proportional to the fourth power of the field. This deviation is shown to be not necessarily in disagreement with the basis of the Fowler-Nordheim theoretical field current equation.
Trusted P2P computing environments with role-based access control

A P2P computing environment can be an ideal platform for resource-sharing services in an organisation if it provides trust mechanisms. Current P2P technologies offer content-sharing services for non-sensitive public domains in the absence of trust mechanisms. The lack of sophis- ticated trust mechanisms in the current P2P environment has become a serious constraint for broader applications of the technology although it has great potential. Therefore in this work an approach for securing transactions in the P2P environment is introduced, and ways to incorporate an effective and scalable access control mechanism - role-based access control (RBAC) - into current P2P computing environments has been investigated, proposing two different architectures: requesting peer-pull (RPP) and ultrapeer-pull (UPP) architectures. To provide a mobile, session- based authentication and RBAC, especially in the RPP architecture, lightweight peer certificates (LWPCs) are developed. Finally, to prove the feasibility of the proposed ideas, the RPP and UPP RBAC architectures are implemented and their scalability and performance are evaluated.
Calibration of Accelerometer Output for Ambulatory Adults With Multiple Sclerosis

Abstract Motl RW, Snook EM, Agiovlasitis S, Suh Y. Calibration of accelerometer output for ambulatory adults with multiple sclerosis. Objectives To examine the association between the rates of accelerometer activity counts and energy expenditure during walking in persons with multiple sclerosis (MS) versus controls and then to calibrate the output of accelerometers for computing time spent in light, moderate, and vigorous physical activity based on common metabolic equivalent unit categories in persons with MS. Design Mixed-model design. Setting Laboratory. Participants People with MS (n=24) and people without MS (n=24) who were similar in age, sex, height, and weight. Interventions The participants undertook three 6-minute periods of walking at 3.2, 4.8, and 6.4km·h −1 on a motor-driven treadmill. Main Outcome Measures Activity counts and energy expenditure were measured with an accelerometer worn on the right hip and open-circuit spirometry, respectively. Results The results indicated that (1) persons with MS had greater energy expenditure, but not activity counts, during walking on a treadmill than did controls; (2) there was a strong linear relationship between activity counts and energy expenditure during treadmill walking, but the slope of the relationship was steeper in persons with MS than in controls; and (3) the cut-points for light, moderate, and vigorous physical activity were lower in persons with MS than in controls. Conclusions Such findings provide evidence for a strong linear relationship between activity counts and energy expenditure during walking in persons with MS and cut-points based on counts per minute for quantifying time spent in light, moderate, and vigorous physical activity using accelerometers in this population.
Remote data checking using provable data possession

We introduce a model for provable data possession (PDP) that can be used for remote data checking: A client that has stored data at an untrusted server can verify that the server possesses the original data without retrieving it. The model generates probabilistic proofs of possession by sampling random sets of blocks from the server, which drastically reduces I/O costs. The client maintains a constant amount of metadata to verify the proof. The challenge/response protocol transmits a small, constant amount of data, which minimizes network communication. Thus, the PDP model for remote data checking is lightweight and supports large data sets in distributed storage systems. The model is also robust in that it incorporates mechanisms for mitigating arbitrary amounts of data corruption.We present two provably-secure PDP schemes that are more efficient than previous solutions. In particular, the overhead at the server is low (or even constant), as opposed to linear in the size of the data. We then propose a generic transformation that adds robustness to any remote data checking scheme based on spot checking. Experiments using our implementation verify the practicality of PDP and reveal that the performance of PDP is bounded by disk I/O and not by cryptographic computation. Finally, we conduct an in-depth experimental evaluation to study the tradeoffs in performance, security, and space overheads when adding robustness to a remote data checking scheme.
Baseline conditions and subtractive logic in neuroimaging.

Discrepancies in the patterns of cortical activation across studies may be attributable, in part, to differences in baseline tasks, and hence, reflect the limits of the subtractive logic underlying much of neuroimaging. To assess the extent of these effects, three of the most commonly used baseline conditions (rest, tone monitoring, and passive listening) were compared using phoneme discrimination as the experimental task. Eight participants were studied in a fMRI study with a 4.1 T system. The three baseline conditions systematically affected the amount of activation observed in the identical phoneme task with major affects in Broca's area, the left posterior superior temporal gyrus, and the left and right inferior parietal regions. Two central findings were: 1) a differential effect of baseline within each region, with the rest baseline condition producing the greatest amount of activation and the passive listening condition producing the least, and 2) systematic baseline task activation in the inferior parietal regions. These results emphasize the relativity of activation patterns observed in functional neuroimaging, and the necessity to specify the baseline processes in context to the experimental task processes.
Dielectric relaxation of surface adsorbed water

Abstract The dielectric behavior of water adsorbed on Na-montmorillonite and γ-alumina oxide is determined at a microwave frequency of 9.8 × 10 9 Hz and over the temperature range from +20°C to −100°C. The dielectric data are correlated with results from previous experiments showing the changes that take place in the sample upon freezing. At temperatures below −10°C all water in excess of two layers between the clay plates has formed ice. Nevertheless, when dielectric data at these temperatures are compared with measurements on similar samples at radiofrequencies, it becomes evident that a dispersion in two layer thick films of adsorbed water, takes place at a frequency of about 10 9 Hz. The variation of the log of the dielectric loss versus the reciprocal of the absolute temperature is linear, and enables one to make the calculation of the Arrhenius activation energy. At radiofrequencies the activation energy in the temperature region from −15°C to −80°C is approximately 12 kcal/mole; at microwave frequencies and in the temperature range from −15°C to −52°C the activation energy is 6 kcal/mole. Various models to explain the results are discussed.
Central Bank Independence, Inflation Variability, and the Revenue Smoothing Hypothesis

This paper examines the revenue-smoothing hypothesis, which posits that an optimizing government will adjust both taxes and inflation to meet shocks to government spending. Our contribution is to examine this through the lens of a new methodology that relates both the first and second moments of inflation rates to central bank independence (CBI) measures. Unlike existing least-squares-based CBI papers, this study uses a maximum likelihood framework that facilitates the direct inclusion of CBI parameters in the residual covariance matrix. This new approach allows for a more intensive use of information contained in the CBI indexes and the estimates obtained are better reflective of CBI influences. Our results provide stronger evidence confirming the revenue-smoothing hypothesis, in particular for those countries with more independent central banks.
Note on the influence of impurity-induced strain on the de Haas-van Alphen effect

Abstract This note points out an error in an earlier paper by the author and shows why the estimates of the influence of impurity induced strain in that paper are typically something like 10 times too large for oscillations due to the belly of the Fermi surface for the noble metals and 5 times too large for those due to the neck.
Heat Shock Protein 72 Response to Exercise in Humans

Heat shock protein (Hsp) 72 is a unique, ubiquitous molecule. In vitro and in vivo animal models have shown that increased Hsp 72 is associated with improved cellular survivability and tolerance to stressors. The primary focus of this article is to review the Hsp 72 protein response to exercise in humans. Various mechanisms regulate post-transcriptional activity and therefore measurement of messenger RNA (mRNA) does not necessarily represent the level of functional Hsp 72. For this reason, this article incorporates only a few studies that assessed Hsp 72 mRNA response to exercise. Although this article focuses on human studies, it also includes some key animal studies to provide insight into the mechanisms of the response of Hsp 72 to stress. Intra-(IC) and extracellular (EC) Hsp 72 have different functions. IC Hsp 72 confers cellular protection from subsequent stressors, while EC Hsp 72 has a whole-body systemic role in antigen presentation and immunity. An acute exercise bout stimulates an increase in both IC and EC Hsp 72. Long-term training and improved fitness increases the rate of availability of IC Hsp 72 in response to stress. Other factors that affect Hsp 72 production include environmental factors, exercise mode, duration and intensity, age, estrogen, and anti-oxidant and glycogen availability. The functions and roles of Hsp 72 also depend on the tissue of origin. This article describes the Hsp 72 response to exercise in relation to the tissue assayed (i.e. skeletal muscle vs lymphocyte) and the origin of the sample (i.e. venous vs arterial serum). Collectively, the reviewed studies reveal exciting and novel research that encourages future investigation in this area.
Atomic co-ordinates for dogfish M4 apo-lactate dehydrogenase.

Abstract Atomic co-ordinates for one subunit of LDH are given in A with respect to a Cartesian co-ordinate system corresponding to the molecular two-fold axes.
A simple bond charge model for vibrations in covalent crystals

Abstract The model of Parr and Borkman for diatomic molecules is extended to covalent crystals givng dispersion curves in good agreement with experiment for diamond. The relation to Phillips' microscopic dielectric bond-charge theory is discussed.
An omnidirectional electromagnet for remote manipulation

An Omnimagnet is an omnidirectional electromagnet comprised of a ferromagnetic core inside of three orthogonal nested solenoids. It generates a magnetic dipole-field with both a variable dipole-moment magnitude and orientation with no moving parts. The design of an Omnimagnet, in which each solenoid has the same dipole moment and minimizes the differences between each of the solenoid's fields, is provided and optimized for strength by tailoring the size of the spherical core used to amplify the solenoids' field. This design is then analyzed using FEA tools and shown to be dipole-like in nature. Various magnetic control methods are then motivated by providing the necessary equations relating the three applied currents to applied field, torque, or force on an adjacent magnetic device. Finally, the optimal design is constructed and its utility is demonstrated by driving a helical capsule endoscope mockup through a transparent lumen.
Montessori Improved Cognitive Domains in Adults with Alzheimer's Disease

Montessori materials were used in two adult day-care centers to slow cognitive decline in adults with Alzheimer's disease. Using a within-subject design, participants in one adult day care received...
A red/white selection for Saccharomyces cerevisiae auxotrophs

Red pigment production in yeast cells with adel or ade2 mutations has been exploited to develop a method of identifying specific amino acid auxotrophs. Amino acid auxotrophs carrying mutations in adel or ade2 show delayed pigment production at sub-optimal amino acid levels. This delay allows selection of amino acid auxotrophs following mutagenesis, since red pigment is produced in prototrophs whilst auxotrophs remain white. This differential colour reaction has been applied to select leucine, lysine and serine auxotrophs. Large numbers of colonies could easily be screened without the need for extensive replica plating.
Ability of GLP-1 to decrease food intake is dependent on nutritional status

Abstract Gut-derived glucagon like peptide-1 (GLP-1) acts in the postprandial period to stimulate insulin secretion and inhibit gastrointestinal motor and secretory function; whether endogenous peripheral GLP-1 inhibits food intake is less clear. We hypothesized that GLP-1 inhibits food intake in the fed, but not fasted, state. There is evidence that GLP-1 acts via stimulation of vagal afferent neurons (VAN); we further hypothesized that the satiating effects of endogenous GLP-1 in the postprandial period is determined either by a change in GLP-1 receptor (GLP-1R) expression or localization to different cellular compartments in VAN. Methods Food intake was recorded following administration of GLP-1 (50 μg/kg or 100 μg/kg) or saline (IP) in Wistar rats fasted for 18 h or fasted then re-fed with 3 g chow. GLP-1R protein expression and localization on VAN were determined by immunocytochemistry and immunoblots in animals fasted for 18 h or fasted then re-fed for 40 min. GLP-1R mRNA level was detected in animals fasted for 18 h or fasted and re-fed ad libitum for 2 h. Results GLP-1 (100 μg/kg) significantly reduced 40 min food intake by 38% in re-fed but not fasted rats (p Conclusion Feeding changes the ability of peripheral GLP-1 to inhibit food intake. GLP-1Rs are trafficked to the plasma membrane in response to a meal. GLP-1 may play a role in regulating food intake in the postprandial period.
Stride smoothness evaluation of runners and other athletes

The purpose of this study was to compare an objective measurement of smoothness between a group of runners and a group of non-runners during running and fast walking. Smoothness was quantified by evaluating the endpoint jerk-cost (JC) at the heel. Subjects walked at a speed of 1.75 m.s(-1) and ran at a speed of 3.35 m.s(-1) on a motor driven treadmill while 2-D kinematic data (60 Hz) were collected from a sagittal plane view. The runners were found to be smoother than the non-runners during both gait conditions, suggesting that this group was inherently smoother in gait related tasks. This study demonstrated that the smoothness of gait can be quantified objectively by evaluating the end-point JC at the heel, and that competitive runners tend to exhibit smoother strides than recreational runners during both running and fast walking.
ENERGETIC PARTICLE INTENSITIES AND ANISOTROPIES NEAR THE SOLAR WIND TERMINATION SHOCK

We address the physics of intensity and anisotropy variations in energetic particles near the solar wind termination shock. We show that rapid, large-amplitude, and highly anisotropic particle events seen upstream of the shock can be understood in terms of the passage across the spacecraft of different filled and unfilled magnetic flux tubes. These are created by large-scale magnetic irregularities that are advected passed the spacecraft and compress as they cross the termination shock. We find significant streaming anisotropies of 50 keV-1 MeV protons in the unshocked solar wind, with front-to-back intensity ratios exceeding a factor of 2, for 5 day averaged values. In contrast, downstream of the shock, our results indicate that the particle distributions are much more uniform and isotropic. However, there is a large-scale, nonzero azimuthal particle anisotropy downstream of the shock. This is caused by the nonradial heliosheath plasma flow necessitated by the nonspherical shock. Our results are consistent with recent Voyager 1 observations.
A Note on Geometric 3-Hypergraphs

In this note, we prove several Turan-type results on geometric hypergraphs. The two main theorems are (1) every n-vertex geometric 3-hypergraph in the plane with no three strongly crossing edges has at most O(n 2) edges, and (2) every n-vertex geometric 3-hypergraph in 3-space with no two disjoint edges has at most O(n 2) edges. These results support two conjectures that were raised by Dey and Pach, and by Akiyama and Alon.
Mental rotation of directional tactile stimuli

Several researchers have developed haptic devices capable of rendering directional stimuli. When these devices are integrated into mobile or handheld devices, it becomes possible for a user to hold the haptic device in any orientation and thereby receive directional stimuli that may be out of alignment with rest of the world. In such cases, it becomes necessary for the user to perform a mental transformation of the directional stimuli, so that the stimuli may be understood in a fixed or global reference frame. This paper addresses two questions: 1. can users perform such transformations and successfully interpret stimuli, and 2. what cognitive processes are involved in these transformations? In our experiments, users performed timed identification of directional tactile stimuli with their hand in a variety of orientations around a single axis. The results show that: 1. users can successfully identify directional stimuli both quickly and accurately, even when the stimuli are rendered in a rotated reference frame, and 2. these tasks involve the mental rotation of a spatial mental representation of the stimulus, and also show evidence of embodiment effects. Furthermore, small angles of rotation (up to ∼40°) incur very little cognitive cost, suggesting that tactile direction stimuli delivered through a handheld device would be robust to variations in user hand orientation.
A COMPARISON OF THE HETEROGENEOUS NUCLEAR RNA OF HELA CELLS IN DIFFERENT PERIODS OF THE CELL GROWTH CYCLE

HeLa cells synthesize heterogeneous nuclear RNA (HnRNA) in the G1, S, and G2 portions of the cell cycle. HnRNA prepared from these various periods was compared by RNA-DNA hybridization experiments. The results indicated that some of the HnRNA molecules were equivalent at all times in the cell cycle, but limitations in the sensitivity of the hydridization reactions, as well as in the spectrum of hybridizing molecules, restrict the conclusions that can be drawn from these comparisons.
Using iPad Technologies To Support Teaching and Learning in CSD

In a clinical project, 37 undergraduate students in a language disorders course with an academic service learning orientation reviewed iPad applications for use in language intervention activities. In this paper, I outline the process for implementing the project, as well as student perceptions of how their involvement in the project affected mastery of course-specific information.
Developing Student, Family, and School Constructs From NLTS2 Data

The purpose of this study was to use data from the National Longitudinal Transition Study–2 (NLTS2) to (a) conceptually identify and empirically establish student, family, and school constructs; (b) explore the degree to which the constructs can be measured equivalently across disability groups; and (c) examine latent differences (means, variances, and correlations) in the constructs across disability groups. Conceptual analysis of NLTS2 individual survey items yielded 21 student, family, and school constructs, and 16 were empirically supported. Partial strong metric invariance was established across disability groups, and in the latent space, a complex pattern of mean and variance differences across disability groups was found. Disability group moderated the correlational relationships between multiple predictor constructs, suggesting the key role of disability-related characteristics in understanding the experiences of youth with disabilities. Implications for future research and practice are discussed.
Micromethod for Determining Total Iron-Binding Capacity by Flameless Atomic Absorption Spectrophotometry

Because of the large quantities of venous blood required, assays of total iron-binding capacity (TIBC) and serum iron are often omitted in diagnostic tests involving small children. As an alternative to the conventional method of assessing TIBC, we developed a micromethod based on flameless atomic absorption spectrophotometry (flameless AAS). Additionally, the standard microprocedure for determining serum iron was modified so that iron concentration could be estimated from the same iron standards used to calculate TIBC. With these procedures, only 20 µl of serum is required to prepare protein-free supernate for measurement of TIBC or serum iron with an atomic absorption spectrophotometer equipped with a graphite furnace and a recorder. The resulting TIBC, serum iron, and computed transferrin saturation values compared well with those obtained by conventional flame atomic absorption spectrophotometry. The correlation was statistically significant at the 99% confidence level. These flameless AAS micromethods provide an accurate and sensitive means of determining both TIBC and serum iron in a total of 40 µl of serum, a quantity easily collected from a fingertip puncture, and hence are appropriate for routine laboratory work in pediatric clinics and for large-scale nutrition surveys.
Equivocation in nonlinear digital carrier synchronizers

The nonlinear (nondecision-aided) digital phase estimator provides rapid phase estimation of an M-ary phase-shift-keyed modulated carrier. This carrier synchronization technique exhibits an anomaly, dubbed equivocation, which can degrade performance. A statistical description of equivocation, a jump in the reference phase trajectory of approximately=2 pi /M rad in a carrier synchronization technique, for the simple case of negligible frequency offset and additive white Gaussian noise is derived. Equivocation is shown to significantly degrade the bit error probability performance even in this benign channel. Since the algorithm as proposed is unsuitable for general use, a modified nonlinear (nondecision-aided) equivocation-free phase estimator is presented. The results of a simulation of this modified architecture developed to demonstrate the improved performance are presented. >
The effect of truncation reduction in fan beam transmission for attenuation correction of cardiac SPECT

A limitation of fan beam transmission imaging using a 40 cm field-of-view scintillation camera is the data truncation that occurs when imaging medium to large-sized patients. With filtered backprojection, truncation may cause bright rings in the reconstructed image. The primary objective of this study is to evaluate a method to extrapolate the truncated transmission data under clinically relevant count density conditions. The method involves obtaining the patient contour by processing the scatter and photopeak emission data, filling the contour with the attenuation coefficient for soft tissue, reprojecting the contour image, extrapolating the truncated projection set with the projections. A long focal length (114 cm) fan collimator is used on one head of a triple camera SPECT system to acquire transmission data. The two remaining detectors are equipped with low energy, ultra high resolution parallel hole collimators. A large thorax phantom (38 cm/spl times/26 cm) and patient data are used to evaluate the method. For SPECT image reconstruction, non-uniform attenuation correction is performed with a truncated attenuation map, an extrapolated attenuation map and the untruncated attenuation map. The SPECT results indicate that image uniformity changes very little using any of the three different attenuation maps when a long focal length fan beam collimator is used for transmission data acquisition. Truncation artifacts that are apparent in the transmission image can be substantially reduced for objects up to 40 cm wide.
Comparison of correlator configurations for FSK demodulation

A new theoretical approach is presented to calculate the error performance of correlator receivers for noncoherent frequency shift keying (FSK) demodulation, which takes arbitrary IF bandlimiting into account and which does not involve any computations beyond a few numerical integrations and the calculation of a few FFTs. This approach is used to compare the performances of different types of correlator configurations. For an optimum choice of IF bandwidth (B=1/T) and deviation ratio
Utility of Silicone Esophageal Bypass Stents in the Management of Delayed Complex Esophageal Disruptions

Background The objective of this study was to review the clinical experience of temporarily placing an endoesophageal silicone salivary bypass stent and its value in managing patients with life-threatening esophageal disruptions. Methods Clinical records of patients undergoing placement of silicone Montgomery salivary bypass stents from June 1998 to September 2007 were reviewed. Seventeen patients had a proven esophageal disruption in the absence of malignancy and with life-threatening sepsis refractory to conventional management. Underlying conditions were iatrogenic trauma from prior pulmonary surgery (4 patients), significant anastomotic leaks after an esophagogastrectomy (4 patients), delayed presentation (> 24 hours) of a perforated esophagus (4 patients), leak after esophageal surgery (3 patients), and esophagobronchial fistula secondary to inflammation and infection (2 patients). Stents were placed without securing, were sutured in place to the esophageal wall at the time of thoracotomy, or were secured by bringing holding sutures through the nostrils and tied over the bridge of the nose. Results In all cases, placement of the esophageal stent led to prompt improvement of the leak and, within a week, improvement of the sepsis. Supportive measures were continued after placement of the stent. Sixteen patients overcame the sepsis with ultimate healing of the esophageal disruption (13 patients) or maturation of the perforation into a chronic fistula (3 patients). Endoscopic stent removal was performed 2 to 16 weeks after placement. No patient had a stricture develop at the disruption site. One patient died of ruptured thoracic aorta. Conclusions Silicone salivary bypass stents serve as an effective way of diverting and excluding the oral-alimentary stream, thereby providing optimal conditions for sepsis control. They are a useful adjunct in the management of complex esophageal conditions.
Changes in Ocular Flora in Eyes Exposed to Ophthalmic Antibiotics

Purpose To determine changes in ocular flora in individuals repeatedly exposed to topical macrolide or fluoroquinolone antibiotics. Design Prospective, controlled, longitudinal study with 1-year follow-up. Participants Forty-eight eyes of 24 patients undergoing serial unilateral intravitreal injection for choroidal neovascularization. Methods Patients received 4 consecutive monthly unilateral intravitreal injections and were then treated as needed. Each patient was randomized to 1 of 4 antibiotics (azithromycin 1%, gatifloxacin 0.3%, moxifloxacin 0.5%, ofloxacin 0.3%) and used only their assigned antibiotic for 4 days after each injection. Conjunctival cultures of the treated eye and untreated fellow eye (control) were taken at baseline and before each injection. All bacterial isolates were tested for antibiotic susceptibility to 16 different antibiotics using the Kirby–Bauer disc diffusion technique. Main Outcome Measures Changes in bacteria composition of the conjunctiva over time. Results In azithromycin-treated eyes, Staphylococcus epidermidis and Staphylococcus aureus accounted for 54.5% and 18.2% of cultured isolates, respectively, at baseline and 90.9% ( P P S epidermidis and S aureus, respectively, but these percentages increased to 63.4% ( P P = 0.24), respectively, after fluoroquinolone exposure. In contrast, the percentage of gram-negative species decreased from 8.7% at baseline to 1.6% ( P S epidermidis isolated from azithromycin-treated eyes was significantly greater when compared with fellow control eyes ( P P Conclusions The percentage of S epidermidis isolated from the conjunctival surface significantly increases after repeated exposure to azithromycin and to a lesser degree fluoroquinolone antibiotics at the expense of other commensal flora. Financial Disclosure(s) The author(s) have no proprietary or commercial interest in any materials discussed in this article.
Overexpression of manganese superoxide dismutase protects against ATP depletion-mediated cell death of proximal tubule cells

We have previously shown that in vivo renal ischemia/reperfusion results in ATP depletion, oxidant production, and manganese superoxide dismutase (MnSOD) inactivation. Current studies were designed to compare the effect of ATP depletion (Antimycin A treatment) on cell death pathways using renal proximal tubular cells and identical cells that overexpress MnSOD. ATP depletion in wild-type cells induced an apoptotic cascade that involved caspase 9 activation; MnSOD overexpressing cells afforded protection against apoptosis. This protection did not appear to involve a cytochrome c-related mechanism, but may be related to altered levels of nitric oxide within the cell. Further studies suggested that nitric oxide was required to protect the renal cells from caspase-mediated cell death. Interestingly, treatment of renal cell extracts with reductants (DTT and ascorbate) enhanced caspase activation. Taken together, these results suggest that cysteine nitrosylation may be playing a role in caspase dysfunction in cells overexpressing MnSOD following ATP depletion.
Charged particle spectra from U-235 and B-10 micropellets and slab coatings

A novel method of utilizing fluorescence generated from the products of nuclear reactions offers the prospect of compact, high efficiency, multi-megajoule lasers. To overcome the problems associated with traditional laser (or energy converter)-fissile material interfaces, such as a uranium coating (low power density and low efficiency) or a gaseous uranium compound (low power density and deleterious effects on the laser kinetics and photon transport), a method suggested elsewhere of employing a reactor using a uranium aerosol fuel, interspersed with a fluorescer medium, is briefly reviewed. The charged particles produced by nuclear reactions in the fuel produce fluorescence in the core region of the reactor, through interactions with the fluorescer. This fluorescence can then be concentrated, to increase the effective power density in the laser medium, and used to drive a photolytic laser.One key issue in the above process is the charged particle spectrum from the fissile aerosol. These issues can be addressed theoretically based on the Dirac chord length distribution technique and an Arcen's function. The charged particle spectrum from a UO2 coating has been generated and benchmarked with the experimental data of Kahn et al., and Redmond et al. Agreement is generally good except near the end of the fission fragment tracks. The validity of this simple technique in approximating the rate of ion energy loss lends confidence to the generation of fission fragment spectra for other geometries (i.e. spherical in which transport efficiencies of over 60% appear achievable) using U, UO2 and U3O8. Work is also extended to the case of B-10 in a variety of configurations which are frequently used in modern energy conversion experimental devices.
Combinatorial evolution of site- and enantioselective catalysts for polyene epoxidation

Selectivity in the catalytic functionalization of complex molecules is a major challenge in chemical synthesis. The problem is magnified when there are several possible stereochemical outcomes and when similar functional groups occur repeatedly within the same molecule. Selective polyene oxidation provides an archetypical example of this challenge. Historically, enzymatic catalysis has provided the only precedents. Although non-enzymatic catalysts that meet some of these challenges became known, a comprehensive solution has remained elusive. Here, we describe low molecular weight peptide-based catalysts, discovered through a combinatorial synthesis and screening protocol, that exhibit site- and enantioselective oxidation of certain positions of various isoprenols. This diversity-based approach, which exhibits features reminiscent of the directed evolution of enzymes, delivers catalysts that compare favourably to the state-of-the-art for the asymmetric oxidation of these compounds. Moreover, the approach culminated in catalysts that exhibit alternative-site selectivity in comparison to oxidation catalysts previously described.
A moderate decrease in temperature inhibits the calcium signaling mechanism(s) of the regulatory volume decrease in chick embryo cardiomyocytes.

Chick cardiomyocytes, when submitted to hyposmotic swelling, exhibit a partial regulatory volume decrease (RVD). A Ca2+ influx by stretch-activated channels signals a taurine efflux and the RVD at 37°C. We evaluated the cell's performance at room temperature. Cardiomyocytes isolated and cultured from 11-day-old chick embryos were submitted to a hyposmotic solution (180 mOsm/kg H2O) at 37°C and at room temperature (26°C). Under these conditions we measured the changes in cell volume as well as the intracellular free Ca2+ (using fura-2). During hyposmotic swelling, cells at 37°C displayed a peak relative volume of 1.61 ± 0.03 and recovery to 1.22 ± 0.04 (N = 14), while cells at 26°C presented a peak swell relative volume of 1.74 ± 0.06 and did not recover (1.59 ± 0.09, N = 9). Transient increases in intracellular Ca2+, which are characteristic of the normal RVD, were observed at both temperatures (29.1 ± 4.5% (N = 8) and 115.2 ± 42.8% (N = 5) increase at 37° and 26°C (P<0.05), respectively). A delay in the Ca2+ transient increase was also observed when the cells were at 26°C (109 ± 34 s compared to 38 ± 9 s at 37°C, P<0.05). At room temperature the RVD does not occur because the calcium transient increase, which is an early event in the signaling of the RVD, is delayed. Also, free calcium is not cleared as in the 37°C RVD. In the normal RVD the free calcium returns to baseline levels. The very high and persistent free calcium levels seen at room temperature can lead to unregulated enzyme activities and may promote irreversible injury and cell death.
Perception of melodic intonation in performances with and without vibrato

We compared perception of mistuned intervals in unaccompanied melodies performed by trumpet, violin, and voice, and examined whether there were differences between the three timbres in performances with and without vibrato. Participants were 144 university music students. Listeners heard the three unaccompanied solo performers in two vibrato conditions (with and without vibrato), and three intonation conditions (selected melodic intervals were in tune, sharp 25 cents, or flat 25 cents relative to equal temperament). All three stimuli were perceived as more out of tune when there was no vibrato compared to vibrato. In performances without vibrato, violin was judged as more out of tune than voice and trumpet across all three tuning conditions. Melodies performed with vibrato were judged differently: Violin was judged as least in tune for intervals mistuned in the flat direction, trumpet was heard as least in tune for intervals mistuned sharp, and voice was judged least in tune when intervals were in tune (r...
Papulopustular skin lesions are seen more frequently in patients with Behçet's syndrome who have arthritis: a controlled and masked study

Objective—To determine the prevalence of acneiform skin lesions (comedones, papules, and pustules) in patients with Behcet’s syndrome (BS) with arthritis. Methods—Study groups included 44 patients with BS with arthritis (32 men, 12 women, mean (SD) age 37.8 (8.9)), 42 patients with BS without arthritis (31 men, 11 women, mean age 35.5 (6.4)), 21 patients with active rheumatoid arthritis (five men, 16 women, mean age 48.8 (14)), and 33 healthy volunteers (28 men, five women,mean age 40.1 (8.1)).All probands and controls were examined by a rheumatologist and a dermatologist, in a prospective and masked protocol. An ophthalmological evaluation was performed if necessary. Skin lesions, including comedones, papules, and pustules, were counted and scored as 0: absent, 1: 1‐5, 2: 6‐10, 3: 11‐15, 4: 16‐20, and 5: >20. Results—Although there was no significant diVerence between the four groups in the prevalence of comedones, the number of papules and pustules was significantly higher in patients with BS with arthritis (p=0.0037 for papules and p<0.0001 for pustules) than in the remaining three groups. Conclusion—Acneiform skin lesions (papules and pustules) seem to be more frequent in patients with BS with arthritis. This suggest that the arthritis seen in BS may possibly be related to acne associated arthritis. (Ann Rheum Dis 2001;60:1074‐1076)
Perspectives on utilizing unique features of microfluidics technology for particle and cell sorting.

Sample preparation is often the most tedious and demanding step in an assay, but it also plays an essential role in determining the quality of results. As biological questions and analytical methods become increasingly sophisticated, there is a rapidly growing need for systems that can reliably and reproducibly separate cells and particles with high purity, throughput and recovery. Microfluidics technology represents a compelling approach in this regard, allowing precise control of separation forces for high performance separation in inexpensive, or even disposable, devices. In addition, microfluidics technology enables the fabrication of arrayed and integrated systems that operate either in parallel or in tandem, in a capacity that would be difficult to achieve in macro-scale systems. In this report, we use recent examples from our work to illustrate the potential of microfluidic cell- and particle-sorting devices. We demonstrate the potential of chip-based high-gradient magnetophoresis that enable high-purity separation through reversible trapping of target particles paired with high-stringency washing with minimal loss. We also describe our work in the development of devices that perform simultaneous multi-target sorting, either through precise control of magnetic and fluidic forces or through the integration of multiple actuation forces into a single monolithic device. We believe that such devices may serve as a powerful “front-end” module of highly integrated analytical platforms capable of providing actionable diagnostic information directly from crude, unprocessed samples - the success of such systems may hold the key to advancing point-of-care diagnostics and personalized medicine.
Assessing the Distraction Potential of Changeable Highway Message Signs

Two experiments were conducted to assess how changeable message signs (CMS) within the right-of-way affect driver behavior and attention. Experiment 1 evaluated whether repeated exposure to irrelevant messages would cause drivers to fail to respond to a safety critical message. Experiment 2 evaluated whether the presence of a driving irrelevant message designed to attract attention would cause drivers to fail to respond to a hazard in the roadway. In both experiments, drivers completed a lengthy (about 50 min) driving simulation in a freeway scenario with CMS every 0.8 km (0.5 mi). Dependent measures were gaze location, response to safety critical message (Exp. 1), and response to spilled load in roadway (Exp. 2). It was found that (1) when headways were short, drivers tend to focus on the roadway and not on a CMS; (2) repeated exposure to irrelevant messages did not cause drivers to miss safety critical messages; (3) salient CMS images (changing faces) did not cause failures to detect a roadway hazard, and (4) the frequency and duration of looks to salient images and travel time messages were similar.