cssi/SciSciGPT-SciSciNet huggingface dataset:
Variations in mean annual tropical cyclone size in the Atlantic

[1] Previous research has focused on predicting tropical cyclone (TC) size in near real time for individual storms. The purpose of this study is to develop models to explain interannual variations in mean Atlantic TC size, as measured by radius of maximum winds (RMAX) and radial extent of 34 knot winds (17 m s−1; R34), and to identify the nature of the relationship between various environmental and storm-related characteristics and TC size. Our analysis demonstrates that mean annual TC size varies systematically among the subbasins in the Atlantic and therefore it is inappropriate to develop a single model for TC size for the entire Atlantic basin. The most important variable for explaining variations in mean annual TC size is the maximum tangential wind (VMAX). VMAX is negatively related to RMAX in all subbasins and positively related to R34 in all subbasins except the Gulf of Mexico, suggesting that years with more intense TCs tend to have smaller (larger) than average RMAX (R34). Other factors, such as the relationships between sea surface temperature, sea level pressure, and Nino 3.4 suggest that environmental factors may play a secondary role in modulating mean annual TC size. Although there are some similarities with the models developed for predicting short-term changes in TC size, our results indicate that it is not appropriate to apply these models to explain variations in TC size at larger spatial scales and longer temporal scales.
Quantum logic for genuine quantum simulators

Recently we proved that there are two non-isomorphic models of the calculus of quantum logic corresponding to an infinite-dimensional Hilbert space representation: an orthomodular lattice and a weakly orthomodular lattice. We also discovered that there are two non-isomorphic models of the calculus of classical logic: a distributive lattice (Boolean algebra) and a weakly distributive lattice. In this work we consider implications of these results to a quantum simulator which should mimic quantum systems by giving precise instructions on how to produce input state, how to evolve them, and how to read off the final states. We analyze which conditions quantum states of a quantum computer currently obey and which they should obey in order to enable full quantum computing, i.e., proper quantum mathematics. In particular we find several new conditions which lattices of Hilbert space subspaces must satisfy.
Persistent Truncus Arteriosus, A Clinical Correlation with the Pathologic Anatomy

(1) In 20 cases of true persistent truncus arteriosus the clinical, radiologic and surgical aspects of the defect have been correlated with the four major anatomic types. (2) From a clinical standpoint, mild cyanosis, a continuous murmur, a single accentuated second heart sound and roentgen evidence of increased pulmonary vascularity should strongly suggest the diagnosis. (3) The diagnosis was established by selective angiocardiography in 13 cases, by surgery in two and by necropsy in six. (4) The prognosis although poor does not appear to be as ominous as previously supposed. Nine of the 20 patients are living at present. Five patients are over five years of age and three patients are ten years or older. (5) A number of surgical procedures are available. Use of pulmonary artery banding in Type I truncus to diminish pulmonary blood flow and a Blalock anastomosis in Type IV with diminished blood flow appears to be beneficial. 1. En 20 casos de tronco arterioso verdadero persistente los aspectos clinico, radiologico y quirurgico del defecto se han correlacionado con cuatro tipos anatomicos principales. 2. Desde un punto de vista clinico, la cianosis moderada, el murmullo continuo, un segundo ruido acentuado y evidencia radiologica de vascularidad pulmonar deben sugerir fuertemente el diagnostico. 3. El diagnostico se establecio por angiocardiografia selectiva en 13 casos, por la cirugia en 2 y por necropsia en 6. 4. El pronostico aunque malo, no parece serlo tanto como se penso antes. Nueve de los 20 enfermos estan vivos hasta ahora. Cinco son mayores de 5 anos y 3 de 10 o mas anos. 5. Hay cierto numero de procedimientos quirurgicos. Parecen beneficos el use del cintado del tronco tipo I para disminuir el flujo sanguineo pulmonar y la anastomosis de Blalock en el tipo IV con flujo aminorado.
Foliar elemental composition of spruce-fir in the southern blue ridge province

Data are presented for what we believe to be the first assessment of the elemental foliar status of red spruce (Picea rubens Sarg.) and Fraser fir [Abies fraseri (Pursh.) Poir.] trees in the high elevation forests of the southern Appalachian mountans.
Controversies in Cardioembolic Stroke

Cardioembolic (CE) stroke mechanisms account for a significant number of ischemic strokes; however, the true burden is likely underestimated. It is critically important to identify patients with CE strokes because these individuals have high recurrence rates and represent a subgroup of patients who may benefit from targeted therapy in the form of anticoagulation or device based treatments. Current guidelines offer recommendations for diagnosis and treatment of these patients; however, important questions remain. First, appropriate cardiac testing in the setting of CE must be individualized and the optimal duration of electrocardiographic monitoring to rule out atrial fibrillation (AF) is unclear. Second, risk stratification tools for AF remain understudied, and there is controversy about which anticoagulant agents are most appropriate. Lastly, important potential CE sources of stroke such as patent foramen ovale have garnered significant attention recently, and debate regarding how to manage these patients persists. In this review, we discuss some of the important controversies in diagnosing and treating patients with possible CE stroke, pointing to areas where future research might be particularly valuable.
Selective use of sentinel lymph node surgery during prophylactic mastectomy.

BACKGROUND. Patients with invasive cancer identified at the time of prophylactic mastectomy (PM) will require axillary lymph node dissection for staging; therefore, many surgeons advocate sentinel lymph node (SLN) surgery at the time of PM. The current study investigates the invasive cancer rate in PM and evaluates factors associated with invasive cancer to guide SLN surgery use. METHODS. Patients undergoing PM at the M. D. Anderson Cancer Center between January 2000 and July 2005 were identified from a prospective database. Clinical, radiographic, and pathologic data were collected. RESULTS. A total of 409 patients (436 PM cases) were identified; 382 underwent contralateral PM (CPM) and 27 underwent bilateral PM (BPM). Cancer was identified in 22 of 436 PM cases (5%). Of these, 14 patients (64%) had ductal carcinoma in situ (DCIS). Only 8 patients (1.8%) had invasive cancer, with a mean tumor size of 5 mm (range, 2–9 mm). There was no difference in the occult cancer rate between CPM and BPM. No cases of invasive cancer were identified in the 23 patients with BRCA mutations. Significantly increased risk of invasive cancer in the PM breast was seen in postmenopausal patients (3.7%; P = .007), patients age >60 years (7.5%; P = .008), and patients with history of invasive lobular carcinoma (9.7%; P = .0002) or lobular carcinoma in situ (LCIS) (7.7%; P = .008). CONCLUSIONS. The frequency of cancer in PM is very low and the majority represents DCIS. Therefore, routine use of SLN surgery in all patients undergoing PM is not warranted. However, patients at higher risk for whom SLN surgery should be considered include older women and patients with a history of lobular cancer or LCIS. Cancer 2006. © 2006 American Cancer Society.
Temperature-dependent minority-carrier lifetime measurements of red AIGaAs light emitting diodes

Electroluminescent decay and internal quantum efficiency measurements are made as a function of temperature on two double heterostructure AIGaAs light emitting diodes (LEDs) that emit in the visible (red) portion of the spectrum. The electroluminescent lifetimes increase by more than a factor of ten and the internal quantum efficiency falls by a factor of three as the temperature is raised from 90 to 400K. By analyzing the data with a model that accounts for the transfer with increasing temperature of the minority-carrier electrons from the direct-gap to the indirect-gap minima in the p-type active layer of these near-crossover LEDs, values for the radiative and nonradiative lifetimes as a function of temperature are obtained. A fit to the radiative-lifetime data results in an estimate of 1.3 × 10−10 cm3s−1 for the room-temperature radiative recombination coefficient of Al0.39Ga0.61As, which is very similar to values reported for GaAs. The nonradiative lifetimes are found to be nearly independent of temperature from 220 to 400K and provide upper limits of 940 and 1250 cms−1 for the interface recombination velocities of the two samples. These values are roughly an order of magnitude lower than any previously reported values for high-Al-content (x > 0.3) AlxGa1−xAs heterostructures.
Modeling of marginal burning state of fire spread in live chaparral shrub fuel bed

Prescribed burning in chaparral, currently used to manage wildland fuels and reduce wildfire hazard, is often conducted under marginal burning conditions. The relative importance of the fuel and environmental variables that determine fire spread success in chaparral fuels is not quantitatively understood. Based on extensive experimental study, a two-dimensional numerical model for vegetation fire spread was developed to simulate laboratory-scale fires. This model is based on a detailed description of the complex heat transfer processes and a simple combustion mechanism contributing to the ignition of solid fuel and fire spread. The fuel bed is described as a porous medium, and the heterogeneous nature of foliage and branch is considered via specific physical properties such as surface area-to-volume ratio, density, and volume fraction. The burning of solid fuel is computed by solving mass and energy equations, including the effects of drying, pyrolysis, and char combustion and the exchanges of mass, momentum, and energy with the surrounding gas. The effects of wind, slope, fuel moisture content, fuel bed arrangement, environmental temperature, and humidity are considered in the numerical model. Computations were performed to compare successful and unsuccessful fire spread cases to highlight the effects of various factors. Numerical results were consistent with the experimental observations of the transition between no fire spread and spread under different fuel and environmental conditions. The simulated heat transfer processes and combustion mechanism in the fuel bed are helpful in identifying factors that determine fire spread success. It was found that the relative importance of modeled convective and radiative heat transfer processes to ignition of solid fuel differed with particle location, and could be switched depending on the wind speed, terrain slope, and fuel bed arrangement.
Preliminary analysis of the relationship between cultural diversity and technology in corporate America

Addresses the issue of cultural diversity in the workplace. Covers the subjects of gender, multiculturalism and age‐related issues, providing a number of statistics for examples. Looks at the impact of technology in areas such as intranets, e‐mail and Web marketing, customer relationship management, virtual offices, automation and virtual teams. Examines the implications of these relationships for corporate America today and in the future.
Fine-needle aspiration biopsy of the distal extremities: a study of 141 cases.

We reviewed our cytopathology databases for an 11-year period to identify all fine-needle aspiration biopsy (FNAB) cases of palpable masses of the hand, wrist, ankle, or foot. Cases were included only if there was a subsequent tissue biopsy or a minimum 1-year clinical follow-up. Of 141 aspirates, 41, 23, 34, and 43 were from the hand, wrist, ankle, and foot, respectively. Specific benign or malignant diagnoses were achievable in 71.6% of cases, whereas the remaining cases were given a descriptive diagnosis (26.2%) or, infrequently, a “suspicious for” diagnosis (2.1%). Overall
Attitudes of Interior Designers toward CADD and CADD Education1

Across the nation, institutions that teach interior design are adding computer-aided drafting and design (CADD) classes to their curriculum with the assumption that the courses will enhance their graduates' marketability. In July 1987, a questionnaire was mailed to practicing interior designers to assess their attitudes toward CADD training for interior design students and toward CADD in general. By understanding the attitudes of practicing interior designers, teaching institutions can better determine if the need for CADD classes exists and what attitudes toward CADD the graduates will encounter when they enter the design field. Responses from a nationwide random sample indicate that practicing interior designers have positive attitudes toward CADD and toward CADD training for students.
Global impact of RNA splicing on transcriptome remodeling in the heart

In the eukaryotic transcriptome, both the numbers of genes and different RNA species produced by each gene contribute to the overall complexity. These RNA species are generated by the utilization of different transcriptional initiation or termination sites, or more commonly, from different messenger RNA (mRNA) splicing events. Among the 30 000+ genes in human genome, it is estimated that more than 95% of them can generate more than one gene product via alternative RNA splicing. The protein products generated from different RNA splicing variants can have different intracellular localization, activity, or tissue-distribution. Therefore, alternative RNA splicing is an important molecular process that contributes to the overall complexity of the genome and the functional specificity and diversity among different cell types. In this review, we will discuss current efforts to unravel the full complexity of the cardiac transcriptome using a deep-sequencing approach, and highlight the potential of this technology to uncover the global impact of RNA splicing on the transcriptome during development and diseases of the heart.
Burning rates of pressed strands of a stoichiometric magnesium-sodium nitrate mix

Abstract : The burning rate of pressed strands made from a stoichiometric mix of magnesium and sodium nitrate was measured in nitrogen over the pressure range 0. 1 to 8.6 MPa. A plot of the logarithm of burning rate vs logarithm of pressure reveals two distinct regions with the 'slope break' occurring near 2 MPa. At the lower pressures, the slope is 0.3; at higher pressures, the slope is 0.05. The burning rate measured at 3.4 MPa was unchanged when oxygen replaced nitrogen; thus, gas-phase reactions do not affect the burning rate.
Modal estimates for the physical parameters of a programmable structure

This work considers the limits of modal analysis based identification of the coefficients on a partial differential equation model of a programmable structure. The programmable structure considered here consists of a cantilevered beam with embedded self sensing piezoceramic actuators and surface mounted control module. A Euler Bernoulli beam model is used as the basic equation of motion. This model is modified to include internal (strain rate) and external (linear viscous) damping mechanisms. In order to model the effects of the embedded piezoceramic as well as the control module, the modulus (EI), density, and damping coefficients are modeled as piecewise constant. An assumed mode approximation is used with off diagonal terms neglected. This numerical approach is then used along with measured frequencies and damping ratios to estimate the various damping and stiffness coefficients. The consistency of the estimates is compared with increasing mode number and the limitations of the procedure are discussed.
Impeding insurgent attacks: The information management agenda

Recent confrontations in Iraq between coalition forces and insurgents have caused much havoc in the way of economic and political reforms. Insurgents use a wide range of tactics, from suicide bombings to kidnappings, to cause tension between the local factions and the Iraqi populace, and between the locals and the coalition forces. The strength of the insurgent strategy emerges from the nature of their attacks: highly erratic, yet potent. All-out-assault on these insurgents is impossible as they cloak themselves and exploit the advantages of guerrilla warfare tactics. In this paper, we will highlight the informational issues that the coalition forces must appreciate in order to curb and curtail these insurgent attacks. While we do not aim to propose any grand strategy to eradicate all insurgent attacks, we do believe that the true weapon that needs to used optimally (effectively and efficiently) against such attacks is information. Whether the insurgents or the coalition forces, the side that is more successful at managing and deploying information potently and with intent will ultimately prevail.
Reply to “Comment on ‘Mechanics of tidally driven fractures in Europa's ice shell’ ”

Abstract Both Lee et al. and Qin et al. consider propagation of a surface initiated tensile crack oriented vertically in an ice sheet of finite thickness with gravitational overburden. Lee et al. assume the crack walls are always in contact and bear normal stress from overburden. In this closed crack scenario, overburden stress increases linearly with depth just as in an ice half-space. Crack walls cannot sustain tension, so the effect of far field tension is concentrated in the material below the crack walls. This leads to the deep crack penetrations of Lee et al. Qin et al., however, assume an open crack scenario. They inappropriately apply normal stress to open crack walls which are exposed to vacuum and so physically cannot sustain a normal stress [Timoshenko, S.P., Goodier, J.N., 1970. Theory of Elasticity, third ed. McGraw–Hill, New York, p. 191]. Since this inappropriate normal stress is horizontally oriented it has the effect of artificially concentrating compressive stress in the material below the open crack. The severely limited crack propagation depths of Qin et al. result from this inappropriate boundary condition on an open crack wall.
Automatic word recognition

Separately spoken individual words can be automatically recognized using a two-dimensional pattern of spectral density versus a nonlinear time base. The pattern for a given word differs from person to person and must be adaptively learned by the machine for each speaker. Simple circuitry is described that learns a word with a single utterance and recognizes it thereafter. The scheme is potentially economical for the spoken equivalent of key entry of data and data inquiry, and a limited vocabulary of commands to the equipment.
Extended hückel β parameters applied to diatomic molecules

From international symposium on atomic, molecular, solidstate theory, and quantum statistics; Sanibel lsland, Florida, USA (20 Jan 1974). Atom-atom separations predicted by extended Huckel theory using four BETA parameter approximations are compared for 15 diatomic molecules. Equilibrium separations R/ sub e/ determined from a new proposed formula for the BETA parameter are compared with R/sub e/'s resulting from the Mulliken-Wolfsberg-Helmholtz, Cusachs, and Jug BETA formulas. Results show that the new BETA formula is best in its prediction of R/sub e/'s. The new formula has the required property of yielding rotationally invariant results. (auth)
Chemistry By Design: A Web-Based Educational Flashcard for Exploring Synthetic Organic Chemistry

Chemistry By Design is a new educational Web site that contains a continuously growing database of natural product and pharmaceutical syntheses. It focuses on providing visitors with an opportunity to learn about the wonders of synthetic organic chemistry by browsing published sequences and viewing each synthetic step individually. Emphasis has been placed on exploiting the wonderful graphical language of organic chemistry to most effectively communicate the educational content as well as to allow visitors to test their knowledge in a variety of different ways. Chemistry By Design is also available as a free application for both Apple iOS and Android devices.
Noncovalent complexes of water-soluble polymers and organoplatinum compounds as potential time-release antitumor agents

Preparation des complexes du platine par reaction de la poly (N-vinyl pyrrolidone) et de la polyoxazolidone en solution aqueuse avec le cis-dichloro (o-phenylenediamine substituee en 4) platine(II). Le (catecholato substitue en 4) (diamino-1,2 cyclohexane) platine(II) et le (phtalato substitue en 4) (diamino-1,2 cyclohexane) platine(II)
Diversity and Technology: The Impact of Diversity on the Role of Civil and Environmental Engineers in Bridging the Digital Divide

After producing statistics illustrating the width of the divide, the authors point out that those on the wrong side of the gap are not only cut off from the benefits of science and technology but also deprived of the opportunity to learn about and perhaps pursue a career in science or engineering. It is argued that if some of these individuals could be brought into the field of civil and environmental engineering, the workforce shortages expected in the coming years could be avoided. An additional benefit to the field would be an increase in diversity, which could pay dividends in the area of creativity. Steps that could be taken by civil and environmental engineers and by local ASCE groups to bridge the divide are outlined.
An Epidemic Model of Violence and Public Support in Civil War

How do civilians respond to violence in civil war, and how do these responses shape combatants' coercive strategies? Conventional wisdom expects civilian victimization to backfire, as a security-minded public "balances" against the side posing the greatest threat to its livelihood and survival. Yet combatants often expect a terrorized population to do the opposite, "bandwagoning" with those most willing and capable to inflict harm. Using an epidemic model of popular support dynamics, I explore the logic of balancing and bandwagoning in irregular civil war. I argue that when civilian strategy is clearly communicated to combatants, civilians are always better off balancing, and combatants are better off avoiding punishment. When civilian choice is not observed, the balancing equilibrium breaks down and patterns of violence depend on the local balance of power. The model's results challenge the view that selective violence is most common in areas of incomplete control. Due to uncertainty over civilian behavior, violence in both divided and perfectly controlled areas can occur in equilibrium, inflicting great costs on civilians. I compare these predictions against the historical record of Soviet counterinsurgency in Western Ukraine, using new micro-level data from the declassified archives of the Soviet secret police. Language: en
Self-management improves asthma

Methods: The study was a single-center, randomized controlled trial of 95 adults (ages 18–55 years) with moderate to severe persistent asthma conducted over 22 weeks. The patients were randomly assigned to receive individualized self-management education or usual asthma care. The three self-management intervention sessions occurred during 30 minutes and were provided by an advanced practice nurse or respiratory therapist who was a certifi ed asthma educator. The sessions included general asthma education, assessment and correction of inhaler technique, initiation of an individualized action plan, and individualized environmental control strategies.
Cooled silicon crystal monochromator test results

High energy insertion devices, used as x-ray monochromators on synchrotron storage rings, require high performance cooling of the primary optic. Monocrystalline materials, such as silicon, inherently provide crystal lattice properties suitable for x-ray diffraction. Silicon, provides excellent thermal and structural properties as well. Free electron lasers also require high performance heat exchanger technology for mirrors. A highly efficient approach to cooling, called `pin post cell,' was developed and fully validated in silicon. However, an additional criteria is imposed on the optic when used as a diffractive crystal. The crystalline structure of the material must not be altered during any step of fabrication. A test program has been completed which evaluated the existing fabrication technology for crystal lattice distortion. X-ray diffraction test results are presented. Currently, we are fabricating an actively cooled crystal that will undergo dynamic testing on the CHESS F2 beamline later this summer.
Targeting Virological Core Groups: A New Paradigm for Controlling Herpes Simplex Virus Type 2 Epidemics

Background. Classic modeling of sexually transmitted diseases has focused on modeling behavioral heterogeneity and designing epidemic control strategies targeted at behavioral core groups. Methods. We analyzed a new mathematical model of herpes simplex virus type 2 (HSV-2) epidemics that includes virological core groups (i.e., groups of individuals with high rates of viral reactivation) and suggest a new paradigm for epidemic control. We used our model, in conjunction with virological data, to determine the potential role of virological core groups in contributing to transmission and the effect that daily antiviral therapy (DAT) could have on reducing transmission if virological core groups were targeted. Results. We estimated that a virological core group (11% of infected individuals) can cause a disproportionately large percentage (44%) of new infections and that a median of only 6.4 person-years of DAT would be necessary to prevent 1 HSV-2 infection. We determined that relatively few individuals would need to receive DAT to substantially reduce the incidence of HSV-2 infection. Conclusion. Identifying and targeting individuals in the virological core group could be an effective and practical public health strategy for reducing transmission. Treating individuals who are high-frequency viral shedders should be evaluated as a strategy for reducing HSV-2 transmission.
Biological Warfare: An Historical Perspective

d d f w n b a M A d b v i v t d n war, the objective is to render the opponent incapable of offering resistance. Conventionlly, this is performed by killing as many soldiers s possible through force of arms. Artillery, bulets, bombs, hand grenades, and land mines all do heir bloody duty. However, the idea that biologial material can kill more effectively and with less ffort, cost, and destruction than bullets makes it n attractive alternative weapon. Indeed, the reease of certain bacteria within the water supply of major city has been the plot of many a spy hriller. Biologic weapons are not new. Most genrals fear the use of “biologicals,” because if the onditions are right, then the biological weapon ay infect the troops unleashing the weapon upon hemselves instead of the enemy. There is also a ultural issue with the use of biologicals; a superior ulture looses them upon an inferior one. Finally, iological weapons, like nuclear ones, can contamnate the battleground for many years to come. hese weapons are ideal for terrorists, because hey strike fear into the target population. A small ial of agent, easily concealed, may be enough to ndanger an entire city. Indeed, biological weapns have made the headlines in our early twentyrst-century world. The use of biological weapons can be broken own into several different ages and categories. he Bible may contain the earliest employment of iologic weapons. Another “common” use of bioogicals, “contamination,” whereby drinking water s tainted through the use of carrion and corpses, oes back to ancient times. Specific agents, such as mallpox, anthrax, and cholera have been used
Sequential versus standard neural networks for pattern recognition: An example using the domain of coronary heart disease

The goal of this study was to compare standard and sequential neural network models for recognition of patterns of disease progression. Medical researchers who perform prognostic modeling usually oversimplify the problem by choosing a single point in time to predict outcomes (e.g. death in 5 years). This approach not only fails to differentiate patterns of disease progression, but also wastes important information that is usually available in time-oriented research data bases. The adequate use of sequential neural networks can improve the performance of prognostic systems if the interdependencies among prognoses at different intervals of time are explicitly modeled. In such models, predictions for a certain interval of time (e.g. death within 1 year) are influenced by predictions made for other intervals, and prognostic survival curves that provide consistent estimates for several points in time can be produced. We developed a system of neural network models that makes use of time-oriented data to predict development of coronary heart disease (CHD), using a set of 2594 patients. The output of the neural network system was a prognostic curve representing survival without CHD, and the inputs were the values of demographic, clinical, and laboratory variables. The system of neural networks was trained by backpropagation and its results were evaluated in test sets of previously unseen cases. We showed that, by explicitly modeling time in the neural network architecture, the performance of the prognostic index, measured by the area under the receiver operating characteristic (ROC) curve, was significantly improved (p < 0.05).
Middle Response Scale Options are Inappropriate for Ideal Point Scales

Purpose The purpose of this study is to provide a theoretical rationale for the inappropriateness of middle response options on the response scales offered on ideal point scales, and to provide empirical support for this argument to assist ideal point scale development.
Sorting with adversarial comparators and application to density estimation

We consider the problems of sorting and maximumselection of n elements using adversarial comparators. We derive a maximum-selection algorithm that uses 8n comparisons in expectation, and a sorting algorithm that uses 4n log2 n comparisons in expectation. Both are tight up to a constant factor. Our adversarial-comparator model was motivated by the practically important problem of density-estimation, where we observe samples from an unknown distribution, and try to determine which of n known distributions is closest to it. Existing algorithms run in Ω(n) time. Applying the adversarial comparator results, we derive a density-estimation algorithm that runs in only O(n) time.
Optical dielectric function of hydrogenated amorphous silicon: Tetrahedron model and experimental results.

A Si-centered tetrahedron model is developed for the determination of the effect of hydrogen on the visible\char21{}near-ultraviolet dielectric function \ensuremath{\epsilon} of a-Si:H. Infrared-absorption and film-density measurements on the a-Si:H films studied here have been utilized to obtain the concentrations and relative fractions of the four tetrahedra, Si-${\mathrm{Si}}_{4\mathrm{\ensuremath{-}}\ensuremath{\nu}}$${\mathrm{H}}_{\ensuremath{\nu}}$ (\ensuremath{\nu}=0\char21{}3), considered in the model and present in the films. These results have indicated that random bonding of hydrogen, with no excess of the dihydride Si-${\mathrm{Si}}_{2}$${\mathrm{H}}_{2}$ tetrahedron, occurs for a-Si:H films deposited at ${\mathit{T}}_{\mathit{s}}$=250 and 450 \ifmmode^\circ\else\textdegree\fi{}C, but that nonrandom bonding with an excess of dihydride occurs for the ${\mathit{T}}_{\mathit{s}}$=110 \ifmmode^\circ\else\textdegree\fi{}C film and for the annealed 250 \ifmmode^\circ\else\textdegree\fi{}C film. The results of the Si-centered tetrahedron model have been used in the effective-medium approximation to obtain predictions for \ensuremath{\epsilon}=${\ensuremath{\epsilon}}_{1}$+i${\ensuremath{\epsilon}}_{2}$ that are in good agreement with experimental results presented here for the a-Si:H films studied. This model has thus been shown to provide a very useful framework for predicting ${\ensuremath{\epsilon}}_{1}$ and ${\ensuremath{\epsilon}}_{2}$ in the visible\char21{}near-uv region and for interpreting the nature of the bonding of hydrogen in these a-Si:H films.
Defensive secretion production in the tenebrionid beetle,Zophobas atratus : Effects of age, sex, and milking frequency.

Beetles were milked of their abdominal defensive secretion at three different frequencies over the first 36 days of adult life. Secretion production decreased greatly with age from a maximum of 94 nmol/day at 4–6 days to a basal level of about 25 nmol/day at 30–40 days. Ethyl- and methylquinone comprised the bulk of the secretion and were most strongly affected by age. Benzoquinone was most strongly affected by milking frequency. An average adult produced an estimated 4445 nmol of total secretion in its 5-month life-span but had reservoirs large enough to store 11,000 nmol. Males produced more secretion than females because of their larger size and inherent sexual differences. As they aged, mated females showed a more rapid decrease in production that virgin females. The defensive system appears to be programed to charge glands rapidly with secretion early in adult life and fall of to a low recharge rate little affected by discharge.
Paraoxonase status and plasma butyrylcholinesterase activity in chlorpyrifos manufacturing workers.

Chlorpyrifos is an organophosphorus (OP) anticholinesterase insecticide. Paraoxonase (PON1) is an enzyme found in liver and plasma that hydrolyzes a number of OP compounds. PON1 polymorphisms include a glutamine (Q)/arginine (R) substitution at position 192 (PON1Q192R) that affects hydrolysis of OP substrates, with the PON1192Q allotype hydrolyzing chlorpyrifos oxon less efficiently than the PON1192R allotype, a variation potentially important in determining susceptibility to chlorpyrifos. We studied 53 chlorpyrifos workers and 60 referents during 1 year and estimated chlorpyrifos exposure using industrial hygiene and employment records and excretion of the chlorpyrifos metabolite 3,5,6-trichloro-2-pyridinol (TCP). Plasma butyrylcholinesterase (BuChE) activity, which may by inhibited by chlorpyrifos exposure, was measured monthly. In addition, plasma samples were assayed for paraoxonase (PONase), diazoxonase (DZOase), and chlorpyrifosoxonase (CPOase) activity to determine PON1 status (inferred genotypes and their functional activity). Linear regression analyses modeled BuChE activity as a function of chlorpyrifos exposure and covariates. We postulated that the level of CPOase activity and the inferred PON1192 genotype (together reflecting PON1 status) would differ between groups and that PON1 status would modify the models of chlorpyrifos exposure on BuChE activity. Chlorpyrifos workers and referents had a 100-fold difference in cumulative chlorpyrifos exposure. Contrary to our hypotheses, mean CPOase activity was similar in both groups (P=0.58) and PON1192Q showed a slight overrepresentation, not an underrepresentation, in the chlorpyrifos group compared with referents (PON1192QQ, 51% chlorpyrifos, 40% referent; PON192QR, 43% chlorpyrifos, 40% referent; PON192RR, 6% chlorpyrifos, 20% referent, P=0.08). In our models, BuChE activity was significantly inversely associated with measures of interim chlorpyrifos exposure, but the biological effects of chlorpyrifos exposure on BuChE activity were not modified by PON1 inferred genotype or CPOase activity.
Interleukin-1 beta activates expression of cyclooxygenase-2 and inducible nitric oxide synthase in primary hippocampal neuronal culture: platelet-activating factor as a preferential mediator of cyclooxygenase-2 expression.

Interleukin-1 beta (IL-1β) is an inflammatory cytokine whose expression is elevated in brain during seizures, ischemia, and injury. Expression of IL-1β and its receptor can also be observed in normal brain. Platelet-activating factor (PAF) is also a dual mediator that promotes neuronal plasticity responses as well as inflammation. We have determined the role of PAF in the regulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) genes by IL-1β in rat primary hippocampal cultures. As assessed by reverse transcriptase/polymerase chain reaction (RT/PCR), recombinant mouse IL-1β (1 nM) led to an induction of COX-2 mRNA which peaked at 2 hours, declined to baseline levels by 4 hours, began to rise again by 6 hours, and remained elevated at 24 hours post-treatment. iNOS mRNA was also induced, but unlike COX-2, its abundance peaked at 4 hours and decreased by 6 hours to a plateau lasting through 24 hours. Pretreatment with PAF antagonist BN50730 blocked induction of COX-2 mRNA by 2-hour IL-1β treatment, and 2-hour treatment with the PAF analog mcPAF mimicked the effects of IL-1β on COX-2 mRNA levels. Following injury, synaptic plasticity changes may be affected by IL-1β-PAF-COX-2 neuronal signaling. J. Neurosci. Res. 58:593–598, 1999. © 1999 Wiley-Liss, Inc.
Efficient memory utilization on network processors for deep packet inspection

Deep Packet Inspection (DPI) refers to examining both packet header and payload to look for predefined patterns, which is essential for network security, intrusion detection and content-aware switch etc. The increasing line speed and expanding pattern sets make DPI a challenging task. Network Processors (NPs) are chosen to perform DPI due to their packet processing performance and programmability. In this paper, we focus on achieving high performance DPI through exploitation of NP's on-chip resources (particularly memory) and inherent parallel processing capability. We study the parallelism in classical DPI algorithms and construct a memory model for different parallel matching methods. Based on the model, we find the optimal organization of state machines that requires minimal on-chip memory space and guides us to high performance NP architectures for DPI. The performance evaluation experiments show that our method can reduce the memory usage by up to 86%. With an Intel IXP28xx NP simulator, we observe that the estimated DPI throughput reaches up to 5 Gbps.
Nanosize stress concentrators at facets in Zn1-xCdxSe/ZnSe multiple quantum well laser structures

Strained layer Zn1-xCdxSe/ZnSe multiple quantum well structures are presently at the core of most blue-green lasers. Laser degradation has focused attention on such issues as residual strain, stress concentration, and dislocation nucleation and propagation in these materials. We fabricated Fabry-Perot cavities through cleavage in Zn1-xCdxSe/ZnSe multiple quantum well structures grown by molecular beam epitaxy with x equals 0.24, 0.3 and x equals 0.50 and a variety of quantum well parameters. The cavity facets were examined by means of atomic force microscopy and lateral force microscopy. We found previously unreported, cleavage-induced nanosize defects related to the discontinuity in the mechanical properties of the strained layer quantum wells. In most cases, the defects can be assimilated to surface delamination features preferentially located at the boundaries between the strained active ternary material and the relatively unstrained binary buffer or barrier layers. Such features run parallel to the interface, exhibit typical depths and surface widths in the 10 nm range, and may act as important stress concentrators during laser processing and operation.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Growth and Distribution of Producer Services: Metro/Nonmetro Differences

Producer services (i.e., services generally used more by businesses than by individual consumers) are increasingly important for the efficient production and distribution of products derived from natural resources and manufacturing. However, these services tend to be concentrated in large metro areas, and research has generally neglected nonmetro areas and whether difference between areas is growing or decreasing. Using data from County Business Patterns, this research considers whether the distribution of producer services changed among three types of areas: a) the dominant metro area, b) other metro and c) nonmetro areas in Washington State between 1979 and 1986. Particular attention is given to the recessionary period of the early 1980s. Although each of the three types of areas saw a shift in employment into these services, the total state share of producer services became more concentrated in the dominant metro area during this time. The recession exacerbated this concentration, and there was no evid...
Late-stage sinking of plutons

Many granodiorite to diorite plutons in the Great Basin of western North America are surrounded by rim monoclines or anticlines that suggest relative downward movement of the plutons while wall rocks were hot and ductile. We propose that such plutons rise to a level of approximately neutral buoyancy and then founder as their densities increase ≈10% during crystallization. Late-stage sinking of intermediate to mafic plutons should be common when wall rocks are rich in weak, low-density minerals such as quartz and calcite. Structures related to sinking will overprint those related to initial pluton emplacement and may be mistaken for regional tectonic structures.
Effects of Certain Nonsteroid Anti-Inflammatory Drugs, Tolbutamide, and Tetrahydroalstonine on Blood Glucose and Carrageenin-Induced Pedal Edema in Rats

Relative oral potencies for preventing carrageenin-induced pedal edema in rats were, in the order of increasing effectiveness: tetrahydroalstonine, phenylbutazone, tolbutamide, cryogenine, chlorpromazine hydrochloride, tetrabenazine, and indomethacin. Pedal injection of carrageenin elevated blood glucose, and phenylbutazone appeared to be the only drug tested clearly capable of blocking this hyperglycemic effect at an anti-inflammatory dosage. In the absence of carrageenin injection, all of the test agents elevated blood glucose 7-13 hr. after their administration. In rats with alloxan-induced hyperglycemia, orally administered tetrahydroalstonine was effective in reducing elevated blood glucose, as was tolbutamide and subcutaneous protamine zinc insulin. Cryogenine raised blood glucose levels even further, while tetrabenazine did not alter the hyperglycemia significantly.
Intermediate valence in alloys of SmSe with SmAs

Results are presented for lattice-parameter and magnetic-susceptibility measurements on a series of solid solutions of SmSe with SmAs. The lattice parameter shows a continuous transition (collapse in excess of Vegard's law) with increasing SmAs concentration similar to the valence transition in SmSe under increasing pressure. The estimated average Sm valence increases from divalent to trivalent as the SmAs concentration increases from 0 to 70%. This behavior is compared with the previously observed first-order valence transition in the solid solutions of SmS with SmAs at 5 to 10 at.% SmAs. The magnetic susceptibilities of the $\mathrm{Sm}{\mathrm{Se}}_{1\ensuremath{-}x}{\mathrm{As}}_{x}$ alloys with $xl0.1$ show a temperature dependence characteristic of a mixture of divalent and trivalent Sm ions. At higher concentrations of As the behavior is characteristic of Sm ions with intermediate valence.
A review of Magnetic Suspension and Balance Systems

This paper traces the development of Magnetic Suspension and Balance Systems (MSBSs) for use in wind tunnels. The expression MSBS implies a system that can both suspend a model and also measure the forces and moments acting on the model. This avoids the need for any mechanical support of the model. An MSBS uses electromagnets located outside the test section walls to create magnetic fields inside the test section. Measurement of the electrical current flowing in each of the electromagnets can be used to determine the forces and moments acting on the suspended model. An MSBS is capable of supporting a model with an internal magnetized core subject to gravity, aerodynamic, and inertial loads. The model must have a core made of either a permanent magnet, magnetized soft iron, or a solenoid. The position of the suspended body is inherently unstable. A closed-loop control system which includes a position sensing system has to control the position of the body by controlling the applied magnetic fields. This paper includes a discussion of all the known MSBSs and the outlook for larger systems.
Effect of magnetic pole arrangement on core loss in laminated high-speed magnetic journal bearings

Power losses in magnetic journal bearings as compared to rolling element or fluid film bearings are very low and normally negligible. However, as operating conditions become more severe, the power losses in magnetic bearings must be considered. This paper examines the effect of magnetic pole arrangement on the core loss of a magnetic journal bearing at high-speed and high-flux-density operation. Experimental core loss results are presented for rotational speeds up to 3.1 million DN and flux densities up to 1.60 T. These results are for a magnetic bearing constructed of cobalt iron. The results are compared to existing results for low-speed operation of silicon iron magnetic journal bearings. Results show that a paired pole arrangement gives a slightly less core loss than an alternating pole arrangement, and that this advantage is not necessarily negligible at high speeds and high flux densities for the cobalt iron bearing.
A critical stem–loop structure in the CR4–CR5 domain of mammalian telomerase RNA

Telomerase is an enzyme that maintains telomere length by adding telomeric sequence repeats onto chromosome ends. The telomerase ribonucleoprotein complex consists of two essential components, a reverse transcriptase and an RNA molecule that provides the template for telomeric repeat synthesis. A common secondary structure of vertebrate telomerase RNA has been proposed based on a phylogenetic comparative analysis of 35 sequences. Here we report the identification of an additional essential base-paired region in the CR4–CR5 domain of mammalian telomerase RNA, termed P6.1. Mouse telomerase RNAs with mutations that disrupted base pairings in the P6.1 helix were unable to reconstitute telomerase activity in vivo. In contrast, an RNA mutant with compensatory mutations that restored base pairings in the P6.1 helix restored telomerase activity. In an in vitro reconstitution system stable base pairing of the P6.1 stem was required for the RNA–protein interaction between the CR4–CR5 domain and the telomerase reverse transcriptase (TERT) protein. Interestingly, two RNA mutations, one that extends the P6.1 stem and one that alters the conserved nucleotides of the L6.1 loop, allowed RNA–protein binding but significantly impaired telomerase activity. These data establish the presence of the P6.1 stem–loop and its importance for the assembly and enzymatic activity of the mammalian telomerase complex.
High-throughput CORDIC coprocessor for signal and display processing

A GaAs application-specific integrated circuit (ASIC) has been designed to provide 40 million nonlinear operations (trigonometric functions, divisions, and multiplications) in a configuration that is compatible with many sensor preprocessing and display processing applications. The ASIC is based on the Coordinate Rotation by Digital Computer (CORDIC) algorithm and will be fabricated with Honeywell's low-power, high-speed complementary heterostructure field-effect transistor (C-HFET) GaAs process. The CORDIC chip can be used for radar electrooptic sensor preprocessing and display coordinate transformation applications. It is shown how one CORDIC ASIC could replace several digital signal processors in, e.g., future synthetic vision systems. The C-HFET GaAs CORDIC has four times higher throughput than CMOS implementations of the same algorithm. Implementation of the same functions with off-the-shelf silicon ASICs would require four times higher power and yield 16 times lower throughput. >