cssi/SciSciGPT-SciSciNet huggingface dataset:
1183 LUNG PRESSURE VOLUME CURVE IN PREMATURE INFANTS WITH PDA

The effects of a left to right shunt through a patent ductus arteriosus (PDA) on the mechanical properties of the lung were evaluated in 16 premature infants, mean BW 1130 g, GA 30 weeks. All infants required mechanical ventilation and pressure volume (P/V) curves were constructed using the difference between airway and esophageal pressure as transpulmonary pressure (PL) and the tidal volume measured simultaneously at different peak inspiratory pressures. Results of lung compliance (CL) (ml/cmH20×kg) were compared with those obtained in normal infants and prematures with hyaline membrane disease (HMD).
Heat transfer from continuous moving fibers in a micropolar fluid

The laminar micropolar boundary layer in axial flow along a continous moving fiber is studied using the theory of micropolar fluids formulated by Eringen. The fiber filament, is taken as a cylindrical cone that moves steadily through an otherwise quiescent environment. The governing equations for momentum angular momentum and energy have been solved numerically. It has been found that the heat transfer rate increases with increasing values of the dimensionless material parameters of the fluid as well as a reduction in the diameter of the filament.
Pathophysiology of endolymphatic hydrops.

Endolymphatic hydrops of the nonprogressive type occurs in response to a single traumatic or toxic insult of limited duration and although it may result in permanent deficits in sensorineural function, there is total subsidence of vestibular symptoms. Endolymphatic hydrops of the progressive type, on the other hand, appears to be the result of permanent impairment of endolymph resorption and is caused principally by disorders of the endolymphatic sac. It occurs in Meniere's disease, syphilitic labyrinthitis and the delayed hydrops syndrome. In addition to deafness of varying extent, it is characterized by episodic vertigo and sometimes by Hennebert's sign. Histological studies suggest that the acute vertiginous episodes are caused by potassium intoxication following ruptures of the membranous labyrinth and that Hennerbert's sign is caused by vestibular fibrosis.
Cartographic Interaction Primitives: Framework and Synthesis

AbstractA cartographic interaction primitive is a basic unit of interactivity that is combined with other primitives in sequence when using interactive maps. The construction of a taxonomy of these basic interaction primitives is considered the ‘grand challenge of interaction’, as such taxonomies provide a consistent lexicon for describing map-based interaction strategies and interface designs, inform the design of scientific experiments to investigate the nature of cartographic interaction, and ultimately lead to design and use guidelines for interactive maps. The purpose of this research is not to offer a new framework of interaction primitives—as there are many in existence—but to organize and synthesize extant strategies for parsing interaction within Cartography and the related fields of Human–Computer Interaction, Information Visualisation, and Visual Analytics into a logical framework. Norman’s stages of action model provides a useful foundation for conceptualizing interaction primitives, with orga...
Direct simulation Monte Carlo aerosol dynamics: Collisional sampling algorithms

Abstract The computation of nuclear aerosol evolution is complicated, and a study of the direct simulation Monte Carlo (DSMC) technique to elucidate the role of various physical phenomena that influence the evolution has been undertaken. In our previous works, we explored important new directions by including most coagulation mechanisms like Brownian, gravitational, turbulence, and reduced the computation time using the Metropolis sampling algorithm for collisional sampling. In this paper, we further explore other sampling algorithms – the no time counter (NTC) and modified direct sampling algorithms. A comparison study on the four sampling algorithms – direct, the Metropolis, the NTC and modified direct sampling algorithms has been made and the results are discussed in this work. From the results, we are able to conclude that the Metropolis sampling algorithm can be used for the simulations as it provides more accurate results and is also time efficient in comparison to the NTC and modified direct sampling algorithms.
A second order singular linear system arising in electric power systems analysis

Abstract The linear system Mx¨ + (∝ M+ β) K)[xacute] + KX= F with M singular, is decomposed into two linear systems, one singular and one non-singular. The singular ono is solved explicitly in terms of M, K, f, a, S and analysed.
A high-temperature superconducting receiver for nuclear magnetic resonance microscopy

A high-temperature superconducting-receiver system for use in nuclear magnetic resonance (NMR) microscopy is described. The scaling behavior of sources of sample and receiver-coil noise is analyzed, and it is demonstrated that Johnson, or thermal, noise in the receiver coil is the factor that limits resolution. The behavior of superconductors in the environment of an NMR experiment is examined, and a prototypical system for imaging biological specimens is discussed. Preliminary spin-echo images are shown, and the ultimate limits of the signal-to-noise ratio of the probe are investigated.
The effects of season, temperature and salinity on the oxygen consumption of bivalve gill tissue

Abstract 1. 1. Oxygen consumption of gill tissue from Crassostrea virginica, Mercenaria mercenaria, Modiolis demissus and Mytilus edulis was measured at salinities of 5, 10, 15, 20, 25 and 30 ppt and at temperatures of 10, 18 and 26°C during winter and summer. 2. 2. The seasonal differences were variable, i.e. winter values greater than, the same as and less than the corresponding summer values were observed. 3. 3. Oxygen consumption was greater at higher temperatures. Summer as compared to winter Q 10 values tended to be higher from 10–18°C and lower from 18–26°C. 4. 4. Season and experimental temperature modified only slightly the effects of experimental salinity. 5. 5. Oxygen consumption was relatively constant from 5–30 ppt for Crassostrea and Mytilus , but was greater at low salinities for Mercenaria and Modiolus . The effect of salinity on oxygen consumption of isolated gill does not appear to be correlated with the lower salinity boundaries of the whole animals.
Waveform modeling of the slab beneath Japan

[1] The tomographic P wave model for the Japan subduction zone derived by Zhao et al. (1994) has two very striking features: a slab about 90 km thick with P wave velocities 3– 6% higher than the surrounding mantle and a mantle wedge with 6% low-velocity anomalies. We study three-component seismograms from more than 600 Hi-net stations produced by two earthquakes which occurred in the downgoing Pacific Plate at depths greater than 400 km. We simulate body wave propagation in the three-dimensional (3-D) P wave model using 2-D finite difference (FDM) and 3-D spectral element (SEM) methods. As measured by cross correlation between synthetics and data, the P wave model typically explains about half of the traveltime anomaly and some of the waveform complexity but fails to predict the extended SH wave train. In this study we take advantage of the densely distributed Hi-net stations and use 2-D FDM modeling to simulate the P-SV and SH waveforms. Our 2-D model suggests that a thin, elongated low-velocity zone exists atop the slab, extending down to a depth of 300 km with an S wave velocity reduction of 14% if a thickness of 20 km is assumed. Further, 3-D SEM simulations confirm that this model explains a strong secondary arrival which cannot easily be imaged with standard tomographic techniques. The low-velocity layer could explain the relatively weak coupling associated with most subduction zones at shallow depths (<50 km), generally involving abundant volcanic activity and silent earthquakes, and it may also help to further our understanding of the water-related phase transition of ultramafic rocks, and the nature of seismicity at intermediate depths (70–300 km).
Three-Dimensional Lattice Logic Circuits, Part I: Fundamentals

Fundamentals of regular three-dimensional (3D) lattice circuits are intro- duced. Lattice circuits represent an important class of regular circuits that allow for local interconnections, predictable timing, fault localization, and self-repair. In ad- dition, three-dimensional lattice circuits can be potentially well suited for future 3D technologies, such as nanotechnologies, where the intrinsic physical delay of the irreg- ular and lengthy interconnections limits the device performance. Although the current technology does not offer a menu for the immediate physical implementation of the proposed three-dimensional circuits, this paper deals with three-dimensional logic cir- cuit design from a fundamental and foundational level for a rather new possible future directions in designing digital logic circuits.
Fabrication of Nanoscale Bioarrays for the Study of Cytoskeletal Protein Binding Interactions Using Nanoimprint Lithography

The authors describe a high-throughput patterning process used to create arrays of molecular-scale features for the study of cytoskeletal protein binding interactions. The process uses a shadow-evaporated metal mask to facilitate lift-off of features defined by nanoimprint lithography. This simple and robust approach alleviates difficulties in pattern transfer of ultrasmall features and results in arrays of highly ordered sub-10 nm features which are then functionalized with extracellular matrix proteins. Application of these arrays is demonstrated in cell spreading assays.
Gas hydrate that breaches the sea floor on the continental slope of the Gulf of Mexico

We report observations that concern formation and dissociation of gas hydrate near the sea floor at depths of ∼540 m in the northern Gulf of Mexico. In August 1992, three lobes of gas hydrate were partly exposed beneath a thin layer of sediment. By May 1993, the most prominent lobe had evidently broken free and floated away, leaving a patch of disturbed sediment and exposed hydrate. The underside of the gas hydrate was about 0.2 °C warmer than ambient sea water and had trapped a large volume of oil and free gas. An in situ monitoring device, deployed on a nearby bed of mussels, recorded sustained releases of gas during a 44 day monitoring period. Gas venting coincided with a temporary rise in water temperature of 1 °C, which is consistent with thermally induced dissociation of hydrate composed mainly of methane and water. We conclude that the effects of accumulating buoyant force and fluctuating water temperature cause shallow gas hydrate alternately to check and release gas venting.
Ultra-wideband optically addressed transmitting phased array

In this paper we present an ultra-wideband optically addressed transmitting phased array antenna, consisting of ultra-wideband and tunable RF synthesizer, optically addressed phase feeding network, and high-speed photodetector integrated wideband antenna array. RF source generation and optical feed network are capable of cover the frequency range up to 50GHz. A set of 4×4 antenna arrays, such as horn and patch antennas in Ka band are designed, fabricated and characterized, ready for the further integration to the 1×4 ultra-wideband transmitting array system. The array is designed to able to sweep over ±30° from the broadside. Embedded electronic control is developed for both RF synthesizer and optical feed network control. The system is consolidated into a portable cart for field test.
The metadata approach to accessing government information

Abstract This introductory essay provides an overview of the articles in this special issue. In addition, it provides a brief historical sketch of the development of GILS and offers several perspectives on the critical importance of metadata for resource description and resource discovery. Interoperability is presented as a key challenge in integrating access to the various government information locator services being deployed at state and Federal levels.
Post-Release Displacement Uncertainty of Micro-Cantilevers Due to Anchor Over/Under Etching

In this paper we follow an analytical and finite element modeling approach to study the effect of anchor over/under-etch on the post-release tip displacement of MEMS cantilever beams. We show that the last release step is particularly critical in controlling the beam’s post-release displacement, which is of primary importance in a variety of applications. In this paper we isolate the effects of mean stress and imperfect anchor. We assume negligible gradient stress since its effect has been studied in detail in the literature. Beams with perfect anchors and zero under-etch are also presented for comparison. The results emphasize that through careful control of the fabrication parameters and anchor structure, the initial displacement profile and thus performance of micro-cantilevers can be accurately controlled.Copyright © 2008 by ASME
Pathogenesis of Experimental Ebola Virus Infection in Guinea Pigs

The subtype Zaire of Ebola (EBO) virus (Mayinga strain) was adapted to produce lethal infections in guinea pigs. In many ways, the disease was similar to EBO infections in nonhuman primates and humans. The guinea pig model was used to investigate the pathologic events in EBO infection that lead to death. Analytical methods included immunohistochemistry, in situ hybridization, and electron microscopy. Cells of the mononuclear phagocyte system, primarily macrophages, were identified as the early and sustained targets of EBO virus. During later stages of infection, interstitial fibroblasts in various tissues were infected, and there was evidence of endothelial cell infection and fibrin deposition. The distribution of lesions, hematologic profiles, and increases in serum biochemical enzymes associated with EBO virus infection in guinea pigs was similar to reported findings in experimentally infected nonhuman primates and naturally infected humans.
The effect of variation of molecular geometry of a transition metal oxide cluster on the valence band density of states

Abstract Past investigations have correlated XPS valence band broadening with the increase in size of clusters of supported atoms on inert substrates. The theoretical effects of geometrical variation for a given cluster size has not been reported. In this report we show that the broadening effect can be due to size, but can also occur due to the geometrical variation within a given cluster. If a valence band density of states curve for the geometrical variations of the smallest possible cluster of MnO, namely (MnO) 2 , is constructed, it is bulk like in appearance.
Subendocardial resection for refractory ventricular tachycardia: effects on ambulatory electrocardiogram, programmed stimulation and ejection fraction, and relation to outcome

The inducibility of ventricular tachycardia by programmed stimulation was correlated with ventricular ectopic activity on ambulatory electrocardiogram, ejection fraction and clinical outcome in 36 patients after endocardial resection for medically refractory ventricular tachycardia. Ventricular tachycardia was nonin-ducible postoperatively in 25 patients and was inducible in 11. After administration of antiarrhythmic drugs, ventricular tachycardia could no longer be induced in four patients and remained inducible in the other seven patients. All 36 patients had postoperative and 20 had preoperative ambulatory electrocardiograms obtained while they were not receiving drug therapy. Pre- and postoperative ambulatory electrocardiograms did not differ in mean hourly ventricular premature depolarization frequency, Lown arrhythmia grade or change in grade (pre- vs. postoperative). The majority of postoperative patients had repetitive forms of ventricular arrhythmia postoperatively and there was no difference between patients with inducible and noninducible ventricular tachycardia in regard to Holter monitoring characteristics. There was no significant difference in postoperative ejection fraction between patients with inducible and noninducible ventricular tachycardia postoperatively. Ventricular tachycardia has recurred in 2 of 29 patients who had no inducible tachycardia at the time of hospital discharge and were followed up for a mean of 1 year; it has recurred in one of seven patients in whom it was still inducible at the time of hospital discharge and who were followed up for a mean of 7 months. It is concluded that: 1) the performance of subendocardial resection does not affect the level of ventricular ectopic activity; 2) ventricular ectopic activity measured by postoperative 24 hour electrocardiographic monitoring is not related to postoperative inducibility of ventricular tachycardia; and 3) the presence of inducible ventricular tachycardia despite antiarrhythmic therapy or high grade ventricular ectopic activity does not preclude a good outcome after subendocardial resection for refractory ventricular tachycardia.
Radionuclide scanning--new applications in urology

The current status of nuclear renal scanning and function evaluation is summarized. The indications for renal imaging are discussed. Techniques for measurement of split and total renal function are reviewed. Special attention is given to the role of renography (conventional and diuretic) in the evaluation of the obstructed kidney.
Dosimetric guidance on using brachytherapy (low-dose-rate or high-dose-rate) to offset a flawed permanent prostate implant.

Abstract Purpose To provide practical dosimetric advice on mending suboptimal permanent implants using low-dose-rate (LDR) or high-dose-rate (HDR) brachytherapy. The problem is to make the combination of the two radiation treatments (the initial, flawed one and the compensatory boost) clinically isoeffective with the planned dose. Methods and Materials The device of isoeffective dose is the appropriate tool for this purpose as it accounts for the physical (temporal distribution of dose) and biologic (radiosensitivity, repair kinetics, proliferation rate) treatment settings. Results I give, as a function of separation time from the initial, flawed treatment, and stratified by risk group representative values for the additional dose (low-dose-rate or high-dose-rate) needed to make the combined treatment isoeffective with a prescription of 144 Gy of permanently implanted 125 I seeds. Conclusions Although the isoeffective dose concept, within the constraints stated in the text, is rigorously valid, its practical implementation depends importantly on the relevant radiobiologic parameters, and in this respect the reader is urged to use his own critical judgment.
Relativistic many-body theory, quantum chromodynamics and neutron stars/supernova

Abstract A systematic account of relativistic many-body theory is presented with particular emphasis on the renormalization of finite temperature and density Green's functions and the thermodynamic potential. This is then applied to Quantum Chromodynamics (QCD), the non-Abelian gauge theory of the strong interaction (quarks and gluons), to demonstrate the applicability of perturbation theory of the strong force at high baryon number densities. For an accepted range of the elementary particle parameters, the quark mass and the quark-gluon structure constant, it is shown that QCD determines the major characteristics of heavy mass neutron stars and predicts two supernova mechanisms: hydrodynamic bounce and hyperonization.
Low Polarization Voltage and High Sensitivity CMOS Condenser Microphone Using Stress Relaxation Design

Abstract In this paper, a CMOS condenser microphone with high sensitivity and low polarization voltage was designed, simulated and fabricated. Due to CMOS process temperature variant and lattice defects, the poly-membrane would be invoked normal stress and gradient stress. These two residual stresses would deform the membrane and increase the membrane's rigidity. For these concerns, an interlace slots design is utilized to reduce the normal stress up to 90%, and the annealing process is applied to decrease the gradient stress. The acoustical sensitivity was increased considerably to -45dBV at 2.7V bias voltage, and, the noise level is -85dBV at 1KHz.
Dependence of Cooled Reverse-Flow Reactor Dynamics on Reactor Model

Extensive simulations indicate that in most but not all cases the single- and two-phase models predict similar dynamic behavior of a reverse-flow reactor, when catalyst pellet multiplicity does not occur at any point in the reactor. Differences in the predictions are found in some cases close to the dynamic bifurcation loci of a cooled RFR, or in others when the qualitative dynamic behavior is very sensitive to the value of the parameters, such as close to a transition to chaotic behavior. The two models can lead to rather different predictions of the dynamic features when there are large differences between the feed and coolant temperatures.
Sensing of gaseous HF at low part-per-trillion levels using a tunable 2.5-µm diode laser spectrometer operating at ambient pressure

We demonstrate a sensor based on tunable diode laser absorption spectroscopy for the detection of hydrogen fluoride (HF) gas at ambient pressure. Absorption from the HF R(1) ro-vibrational peak at ν = 4038.962 cm−1 (2.476 µm) in the fundamental (Δν = 1) band is measured. A quantitative spectral fit based on HITRAN data is used to account for overlapping spectral peaks of HF and water vapor, with an rms residual noise of 5 × 10−4 absorbance units. The sensor is optimized for the detection of transient variations in HF concentration. We measure noise-equivalent concentrations for HF of 38 parts-per-trillion by volume (ppt) for 1-s integration times and 2.3 ppt for 10-min integration times.
Microbial Pathogenicity in Oral Soft Tissue Diseases

Recent work implicating microbial factors in the pathogenesis of several oral soft tissue diseases is discussed. These conditions include recurrent aphthous ulceration, oral cancer, Sjogren's syndrome, and the oral lesions of AIDS (the acquired immune deficiency syndrome). This paper reviews some recent work on these topics, with emphasis on investigations in our laboratory.
How RNs rescue patients: a qualitative study of RNs' perceived involvement in rapid response teams

Background Patients are admitted to hospitals everyday with clinical conditions that can change dynamically resulting in adverse outcomes. The rapid response team (RRT) intervention is a formalised resource to respond to the nurse's concerns about such patients before code arrest occurs. Registered nurses (RNs) are in a position to recognise critical changes and to rescue patients at the most opportune moments, but little is known about how RNs rescue patients using these increasingly popular teams. Our aims were to investigate how RNs rescue patients in hospitals where RRTs are in place. Methods Fifty participants involved with RRTs participated in semistructured individual interviews in six California hospitals. Data were analysed using coding and constant comparison methods. Results Overall, RNs view RRTs as a helpful and effective safety intervention. RRT RNs and bedside RNs support one another in a synergistic way to prevent adverse patient events during the rescuing process. However, traditional hierarchies and relationships with physicians and supervisors impede some components of RN decision-making during rescuing. Conclusions RNs find the RRT supportive when their patient is at risk or care needs are changing. They benefit from a formalised mechanism that enables immediate access to resources. RRT RNs in this study applied their expertise with critically ill patients to rescue medical and surgical patients. The RRT RN and bedside RNs' interaction influenced the rescuing process. Their role synergy was a value-added contribution to preventing adverse events and to improving patient safety by RNs.
A randomized, controlled, prospective study evaluating the effect of patellar eversion on functional outcomes in primary total knee arthroplasty.

Background: Patellar mobilization technique during total knee arthroplasty has been debated, with some suggesting that lateral retraction, rather than eversion, of the patella may be beneficial. We hypothesized that patients with knees surgically exposed using patellar lateral retraction would have comparable outcomes with patients with knees surgically exposed using patellar eversion. Methods: After an a priori power analysis, 120 patients with degenerative arthrosis were prospectively enrolled and were randomized to one of two patellar exposure techniques during the primary total knee arthroplasty: lateral retraction or eversion. The primary outcome measure was one-year, dynamometer-measured quadriceps strength. The secondary outcome measures evaluated during hospital stay included the ability to straight-leg raise, visual analog scale in pain, walking distance, and length of stay. The secondary outcome measures that were evaluated preoperatively and through a one-year follow-up included the Short Form-36 Physical Component Summary and Mental Component Summary scores, range of motion, quadriceps strength, and radiographic rate of patella baja and tilt. Results: A mixed-model analysis of variance showed no significant differences between the two groups in the one-year outcome measures. At one year postoperatively, quadriceps strength was not different between groups (p = 0.77), and the range of motion significantly improved (p < 0.01) from preoperative values by a mean value (and standard deviation) of 6° ± 17°, with no significant difference (p = 0.60) between groups. The Short Form-36 Physical Component Summary score and Mental Component Summary score significantly improved (p < 0.01) for both study groups from preoperatively to one year postoperatively with no significantly different effects between groups (time × group, p = 0.85 for the Physical Component Summary score and p = 0.71 for the Mental Component Summary score), and the scores were not different at one year after surgery. There were no significant differences between groups in the change in frequency of the radiographic patella baja (p = 0.99) or the radiographic patellar tilt (p = 0.77) from before surgery to one year after surgery. Conclusions: Lateral retraction of the patella did not lead to superior postoperative results compared with eversion of the patella during total knee arthroplasty as evaluated using our primary outcome measure of one-year, dynamometer-measured quadriceps strength or our secondary outcome measures. Level of-Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.
A new beamformer design algorithm for microphone arrays

This paper presents a generic beamformer design algorithm for arbitrary microphone array geometry. It makes efficient use of noise models for ambient and instrumental and microphone directivity patterns. By using a new definition of the target criterion and replacing a multi-dimensional optimization with a much simpler one-dimensional search, we can compute near-optimal solutions in reasonable time. The designed beams achieve noise suppression levels between 10 and 15 dB, for microphone arrays with four to eight elements, and linear and circular geometries. The fast beamformer real-time processing engine consumes less than 2% of the CPU power of a modern personal computer, for a four-microphone array.
The reverse shoulder: Promises and pitfalls

Superior humeral escape, typically seen in patients with cuff tear arthropathy who have loss of the coracoacromial arch, has presented a significant problem for shoulder surgeons. No surgical technique has adequately addressed this problem until the design of the Grammont reverse prosthesis. Although previous constrained and reverse designs have failed, the unique aspect of this device is that it minimizes the forces acting on the glenoid component fixation. Although it should still be considered a salvage device in older, less active patients, it has provided an excellent alternative for this previously hopeless problem.
Tolerance of skin homografts induced in adult mice by multiple injections of homologous spleen cells.

Summary1. Adult mice of the Z(C3H) strain have been made tolerant of skin homo-grafts of the(A X Z) F1 hybrid strain by repeated intravenous and intraperitoneal injections of homologous spleen cells. 2. Repeated intraperitoneal injections of homologous spleen cells generally failed to induce a tolerant state, although 3/75 recipients accepted the homologous skin homotransplant.
L’ostéoclaste et les mécanismes moléculaires de la résorption osseuse

Des trois cellules assurant le remodelage osseux, l’osteoclaste, responsable de la resorption osseuse, est celle dont la fonction et la regulation sont le mieux connues sur le plan cellulaire et moleculaire. L’osteoclaste est d’origine hematopoietique et la differenciation de pre-monocytes en precurseurs osteoclastiques se deroule dans la moelle osseuse, sous le controle de trois facteurs cles, M-CSF, RANKL, le ligand du recepteur RANK et son antagoniste, l’osteoprotegerine (OPG), identifies au cours de la derniere decennie. L’osteoclaste fonctionne de maniere cyclique, alternant des phases migratoires le long de la surface osseuse et des phases de resorption active creant des lacunes osseuses. L’osteoclaste en phase de resorption se caracterise par sa bipolarite morphologique et fonctionnelle. Le pole apical s’attache a la matrice osseuse, possede une pompe a protons ATPasique particuliere, et secrete a travers une bordure en brosse des enzymes lysosomiales et des metalloproteases. Le pole basolateral, en rapport avec le micro-environnement, a pour fonction essentielle le maintien de l’equilibre electrochimique de l’osteoclaste par la coordination de pompes a ions electrogenes, de canaux et d’echangeurs ioniques. En pathologie, une anomalie genetique ou acquise de la regulation de la resorption osseuse peut conduire a une osteoporose, une osteogenese imparfaite ou une osteopetrose selon que la resorption excede la formation osseuse ou au contraire est anormalement diminuee.
Positive enteric contrast material for abdominal and pelvic CT with automatic exposure control: what is the effect on patient radiation exposure?

Abstract Objective To assess the effect of positive enteric contrast administration on automatic exposure control (AEC) CT radiation exposure in (1) a CT phantom, and (2) a retrospective review of patients. Materials and methods We scanned a CT phantom containing simulated bowel that was sequentially filled with water and positive enteric contrast, and recorded the mean volume CT dose index (CTDIvol). We also identified 17 patients who had undergone 2 technically comparable CT scans of the abdomen and pelvis, one with positive enteric contrast and the other with oral water. Paired Student's t-tests were used to compare the mean CTDIvol between scans performed with and without positive enteric contrast. Both the phantom and patient CT scans were performed using AEC with a fixed noise index. Results The mean CTDIvol for the phantom with simulated bowel containing water and positive enteric contrast were 8.2 ± 0.2 mGy, and 8.7 ± 0.1 mGy (6.1% higher than water, p = 0.02), respectively. The mean CTDIvol for patients scanned with oral water and with positive enteric contrast were 11.8 mGy and 13.1 mGy, respectively (p = 0.003). This corresponded to a mean CTDIvol which was 11.0% higher (range: 0.0–20.7% higher) in scans with positive enteric contrast than those with oral water in patients. Conclusions When automatic exposure control is utilized for abdominopelvic CT, the radiation exposure, as measured by CTDIvol, is higher for scans performed with positive enteric contrast than those with oral water.
Software Acoustic Modems for Short Range Mote-based Underwater Sensor Networks

Most recent work in underwater network development has relied on using expensive commercial acoustic modems or on building custom transceivers for each application to establish acoustic communication links among the sensors. Using commercial modems or designing custom hardware may require prohibitive monetary or time investment for many applications. Our work proposes the design of software acoustic modems that can utilize built-in microphones and speakers on the relatively cheap Tmote Invent platforms. The built-in Tmote hardware and the software modem enable acoustic communication in a short range shallow water network. In this paper, we present the initial design and architecture of our acoustic communication system which targets environmental monitoring applications. Our experiments with generic acoustic hardware to profile this underwater communication channel reveal that the channel favors frequencies below 3 Khz, a result which guides the design choices for our FSK software modem. We perform experiments with our software modem/generic hardware system to explore the system's data transfer capability. The data communications experiments confirm the system's capability of transferring information in the order of tens of bits per second for a communications range of up to 10 meters.
Protamine reduces bleeding complications associated with carotid endarterectomy without increasing the risk of stroke

Objectives Controversy persists regarding the use of protamine during carotid endarterectomy (CEA) based on prior conflicting reports documenting both reduced bleeding as well as increased stroke risk. The purpose of this study was to determine the effect of protamine reversal of heparin anticoagulation on the outcome of CEA in a contemporary multistate registry. Methods We reviewed a prospective regional registry of 4587 CEAs in 4311 patients performed by 66 surgeons from 11 centers in Northern New England from 2003-2008. Protamine use varied by surgeon (38% routine use, 44% rare use, 18% selective use). Endpoints were postoperative bleeding requiring reoperation as well as potential thrombotic complications, including stroke, death, and myocardial infarction (MI). Predictors of endpoints were determined by multivariate logistic regression after associated variables were identified by univariate analysis. Results Of the 4587 CEAs performed, 46% utilized protamine, while 54% did not. Fourteen patients (0.64%) in the protamine-treated group required reoperation for bleeding compared with 42 patients (1.66%) in the untreated cohort (P = .001). Protamine use did not affect the rate of MI (1.1% vs 0.91%, P = .51), stroke (0.78% vs 1.15%, P = .2), or death (0.23% vs 0.32%, P = .57) between treated and untreated patients, respectively. By multivariate analysis, protamine (odds ratio [OR] 0.32, 95% confidence interval [CI], 0.17-0.63; P = .001) and patch angioplasty (OR 0.46, 95% CI, 0.26-0.81; P = .007) were independently associated with diminished reoperation for bleeding. A single center was associated with a significantly higher rate of reoperation for bleeding (OR 6.47, 95% CI, 3.02-13.9; P Conclusion Protamine reduced serious bleeding requiring reoperation during CEA without increasing the risk of MI, stroke, or death, in this large, contemporary registry. In light of significant complications referable to bleeding, liberal use of protamine during CEA appears warranted.
Simple expressions for diffraction loss in open resonators

In this article simple closed-form are presented expressions to compute the diffraction loss of open resonators composed of spherical mirrors of circular cross-section. These expressions, which are based on the numerical results of scalar theory, should be useful in designing mirror size for open resonators. Experiments are conducted at W band to demonstrate the accuracy of the expressions. © 1992 John Wiley & Sons, Inc.
Optimal minmax estimation and the development of minmax estimation error bounds

It is often desired to create an optimal estimator of some parameter theta given the observation x. However, the relationship between theta and x may depend on another parameter phi which is unknown to the processor and not of direct interest. In this case, an estimator which performs well for one value of phi may perform poorly for another value of phi . One approach to dealing with this problem is to develop an estimator whose worst case performance evaluated over some range of phi is as good as possible. Such an optimal minmax estimator is derived. The derivation of this estimator also motivates an approach to developing lower bounds on the minmax estimation error achievable by any estimator. >
Attribute Noise-Sensitivity Impact: Model Performance and Feature Ranking

Developing robust and less complex models capable of coping with environment volatility is the quest of every data mining project. This study attempts to establish heuristics for investigating the impact of noise in instance attributes data on learning model volatility. In addition, an alternative method for determining attribute importance and feature ranking, based on attribute sensitivity to noise is introduced. We present empirical analysis of the effect of attribute noise on model performance and how it impacts the overall learning process. Datasets drawn from different domains including Medicine, CRM, and security are employed by the study. Using proposed technique has practical implications by supporting building low volatile, high performance predictive models prior to production deployment. Also the study has implications for research by filling the gap in attribute noise research and its impact.
Oncogenic mutations in melanomas and benign melanocytic nevi of the female genital tract

Background The genetic heterogeneity of melanomas and melanocytic nevi of the female genital tract is poorly understood. Objective We aim to characterize the frequency of mutations of the following genes: BRAF , NRAS , KIT , GNA11 , and GNAQ in female genital tract melanomas. We also characterize the frequency of BRAF mutations in female genital tract melanomas compared with melanocytic nevi. Methods Mutational screening was performed on the following female genital tract melanocytic neoplasms: 25 melanomas, 7 benign melanocytic nevi, and 4 atypical melanocytic nevi. Results Of the 25 female genital tract melanoma specimens queried, KIT mutations were detected in 4 (16.0%), NRAS mutations in 4 (16.0%), and BRAF mutations in 2 (8.0%) samples. Two of the tumors with KIT mutations harbored double mutations in the same exon. No GNAQ or GNA11 mutations were identified among 11 melanomas screened. BRAF V600E mutations were detected in 7 of 7 benign melanocytic genital nevi (100%) and 3 of 4 atypical genital nevi (75%). Limitations Our study is limited by the small sample size of this rare subset of melanomas. Conclusion KIT , NRAS , and BRAF mutations are found in a subset of female genital tract melanomas. Screening for oncogenic mutations is important for developing and applying clinical therapies for melanomas of the female genital tract.
Preparation, structure, growth mechanisms and properties of siloxane composites containing silica, titania or mixed silica–titania phases

Abstract Poly(dimethylsiloxane) (PDMS) [–Si(CH 3 ) 2 O–] networks were prepared by tetrafunctionally endlinking hydroxyl-terminated chains with tetraethoxysilane. Composites were prepared by in situ base-catalysed hydrolysis of an organosilicate and an organotitanate, resulting in the formation of reinforcing silica, titania or silica–titania mixed-oxide fillers within the networks. The growth processes and resulting structures of the reinforcing fillers were studied by small-angle X-ray scattering. Both systems were found to yield dense particles with fractally rough surfaces. Some of the scattering results were used to interpret previously reported mechanical properties obtained on such composites using equilibrium stress–strain measurements in elongation. Of particular interest were mixed silica–titania fillers, since in at least some cases these are known to reinforce PDMS networks better than either silica or titania alone. The scattering results suggest that the corresponding growth processes proceed by the formation of relatively uniform titania particles, followed by the formation of significantly larger silica particles.
Public enemy number one: the US Advertising Council's first drug abuse prevention campaign.

This article explores the Advertising Council's first national drug abuse prevention campaign in the s. Scholarship thus far has demonstrated the ways in which the issue of drug abuse represented a chief political strategy for President Nixon. Evidence from major trade press publications, congressional hearings, and an array of archival sources suggest that this campaign was also part of a public relations crusade on behalf of the advertising industry in response to public criticism of its role in abetting a culture of drug dependence. These institutional and political pressures helped shape drug abuse prevention in the s and for the decades that followed.
Mediators in infrastructure survivability enhancement

Abstract : A key research priority for the next decade is the protection of critical, software-intensive infrastructures (e.g., electric power, banking, telecommunications, and transportation). The problem is complicated by the need to enhance existing systems. The authors describe one approach to survivability enhancement. In 1997, the Internet failed when corrupt data was disseminated at the top level of the Domain Name Service. The authors replicated this failure and developed a solution based on transparent insertion of mediators to enforce survivability policies. Their approach promises to ease survivability enhancement in two ways: (1) transparent insertion eases system architectural evolution, and (2) modularization of survivability policy implementations eases the evolution of both survivability policies and the systems into which their mediators are inserted.
METASTEREOTYPES AND THE BLACK-WHITE DIVIDE: A Qualitative View of Race on an Elite College Campus

We employ qualitative in-depth and focus group data to examine how racial stereotypes affect relations between Black and White undergraduates at the University of Pennsylvania. Specifically, we employ the concept of metastereotypes—Blacks' knowledge and perceptions of the racial attitudes that Whites have of Blacks. Our interest is in the accuracy of Black students' beliefs about Whites' racial attitudes to their group, and the consequences of metastereotypical thinking for Black students' academic performance. We find that the Black students in our sample possess some clear and largely negative metastereotypes concerning how Whites generally think about Blacks, and these metastereotypes are quite accurate. Moreover, these negative group images are at the heart of a key campus “problem”—Whites' hostility to affirmative action and the assumption that Blacks are not qualified to be at the university; and, ironically, most Blacks seem to have internalized a piece of these negative stereotypes. These results are a tangible manifestation of double-consciousness—Blacks' perceptions of themselves both through their own eyes and through the eyes of Whites, and evidence of Steele's theory of stereotype threat, in as much as Black students expend considerable energy attempting to debunk the myth of Black intellectual inferiority.
Hyaluronidase 1 is a vital mediator of brain metastasis in melanoma.

3672 Melanoma has a high propensity to metastasize to the CNS and patients with brain metastases have a poor prognosis. The difficulty of treating these patients is exacerbated by the tendency of melanoma to produce multiple tumors throughout the brain by intracranial metastasis from the initial brain lesion. Both tumor growth within the brain and the seeding of additional lesions requires degradation and remodeling of the brain extracellular matrix. The composition of the brain’s unique extracellular matrix is incompletely understood but its structural organization is based on long strands of very high molecular weight hyaluronic acid decorated with a variety of aggregated proteins and proteoglycans which form networks of crosslinked fibers. Using the human melanoma cell line, MDA MB 435, we found that variant sub-lines derived from lung, bone and brain metastases from orthotopically implanted cells in SCID mice, share a significant upregulation of the hyaluronic acid degrading enzyme, hyaluronidase 1 (Hyal1). Hyaluronic acid zymography showed that the parental 435 cell line expresses barely detectable amounts of Hyal1 and the level of enzyme secreted by cells cultured from the experimental primary tumors at the site of orthotopic implantation is also very low. The striking metastasis-associated up-regulation of Hyal1 suggested that this enzyme might be a central mediator of the metastatic process in melanoma. Our laboratory is especially interested in developing a molecular profile of the events underlying survival and dissemination of tumor cells in the brain. In this study, brain-metastatic variants of luciferase-tagged MDA MB 435 cells (435/Brain) were established in tissue culture and used to examine the role of Hyal1 during tumor growth in the brains of SCID mice. We generated a panel of stable knockdowns of Hyal1 in 435/Brain cells using shRNA in a lentiviral vector. Knockdown of Hyal1 was confirmed by PCR, hyaluronic acid zymography and by analysis of HA digestion products by agarose gel electrophoresis. A control shRNA sequence which has no homology to known human gene sequences was used as a baseline comparison in all experiments. In vivo imaging of luciferase tagged 435/Brain cells was used to visualize growth and metastasis of control and Hyal1 knockdowns after stereotactically guided implantation in the brain striatum of SCID mice. Control and knockdown cells formed tumors at the site of implantation. However, Hyal 1 knockdown strongly diminished the capacity of the cells to migrate from the initial tumor location, in contrast to control cells which rapidly seeded metastases in multiple locations in the brains and spines of the injected animals. These data imply that tumor-derived Hyal1, an enzyme which has been shown to be important in the metastatic spread of several tumor types, can also degrade the form of hyaluronic acid found in the brain extracellular matrix and mediate intra-cranial migration of cancer cells.
Managing Multiple Risks in Dairy Sector

Risks management studies in agrarian and dairy sector predominately focus on the technical methods and the capability to perceive, prevent, mitigate, and recover from a particular type of risk. In related literature, the risk is usually studied as other commodities regulated by market supply and demand, and the farmer’s willingness to pay for an insurance contract. At the same time, risk management analysis largely ignores the significant human nature-based risks, the critical factors for the managerial choice such as the institutional environment and the transaction costs, and diversity of alternative (market, private, collective, public, and hybrid) modes of risk management. This paper incorporates the interdisciplinary New Institutional Economics and presents a comprehensive framework for analyzing risk management in agrarian and dairy sector. The analysis of the modes, efficiency and challenges of risk management in Bulgarian dairy sector brings forth a number of academic, business and policy recommendations.