cssi/SciSciGPT-SciSciNet huggingface dataset:
Hydrogen bonding: single enantiomers from a chiral-alcohol catalyst.

Hydrogen bonding acts as a ubiquitous glue to sustain the intricate architecture and functionality of proteins, nucleic acids and many supramolecular assemblies1,2, but this weak interaction is seldom used as a force for promoting chemical reactions3,4,5. Here we show that a simple chiral alcohol uses hydrogen bonding to catalyse an important family of cycloaddition reactions of a diene with various aldehydes — moreover, this reaction is highly enantioselective, generating only one of the mirror-image forms of each dihydropyran product. This type of catalysis mimics the action of enzymes and antibodies, and is unlike traditional, metal-based catalysts used in organic chemistry6.
Smart nanoparticles for drug delivery: Boundaries and opportunities

Various pharmaceutical particles have been used in developing different drug delivery systems ranging from traditional tablets to state-of-the-art nanoparticle formulations. Nanoparticle formulations are unique in that the small size with huge surface area sometimes provides unique properties that larger particles and bulk materials do not have. Nanoparticle formulations have been used in improving the bioavailability of various drugs, in particular, poorly soluble drugs. Nanoparticle drug delivery systems have found their unique applications in targeted drug delivery to tumors. While nanoparticle formulations have been successful in small animal xenograft models, their translation to clinical applications has been very rare. Developing nanoparticle systems designed for targeted drug delivery, e.g., treating tumors in humans, requires clear understanding of the uniqueness of nanoparticles, as well as limitations and causes of failures in clinical applications. It also requires designing novel smart nanoparticle delivery systems that can increase the drug bioavailability and at the same time reduce the drug's side effects.
The FARC Faces the Empire

Introduction: The Fuerzas Armadas Revolucionarios de ColombiaEjercito del Pueblo (Revolutionary Armed Forces of Colombia-People's Army-FARC-EP) is the most powerful and successful guerrilla army in the world confronting neoliberal regimes and their U.S. backers. It is the dominant political force in over 50 percent of the country's municipalities, fielding a guerrilla army of approximately 18,000 mostly peasant fighters. In addition, it has urban militia units in most major cities and towns and hundreds of thousands of sympathizers throughout the country. Led by Manuel Marulanda, it has been battling the Colombian oligarchy and its authoritarian two-party political system for over three decades. The FARC emerged in 1964 from a peasant movement that had sought five years earlier to establish rural self-governing communities in Marquetalia. The military invaded the peasant communities, destroying their villages and razing their crops. The peasants regrouped and, under the leadership of Marulanda, formed the nucleus of what is today the FARC. The FARC, which retains fraternal relations with the Colombian Communist party, has built its support by supporting agrarian reform (redistribution of land), nationalism (opposition to foreign control of strategic sectors of the economy), democratization (the end of the Liberal-Conservative monopoly of political power), and human rights (the dismantling of the military-landlord-controlled paramilitary groups that terrorize the countryside and the cities). It has taken a principled position against the narco-capitalist politicians and military officials. It protects cocagrowing peasants and taxes the dealers who purchase the leaf in their zones of influence. Contrary to the U.S. State Department propaganda, however, the FARC neither produces nor sells coca or drugs, as the present president of Colombia, Andres Pastrana, admits. From early 1998 to the end of 1999, the FARC has extended its field of operations and the size and scope of those operations: military confron-
Applications of new peptide protective groups 1-- a synthesis of -s-acetamidomethyl dihydrosomatostatin

Abstract A synthesis of bis -S-Acetamidomethyl dihydrosomatostatin is reported in which the C-terminal carboxyl function is protected by the Maq ester function and the N-terminal amine as well as two e-amino groups of lysine residues are protected as Tcroc urethanes. Clean removal of these groups is reported.
Assuring privacy and reliability in crowdsourcing with coding

Crowd workers are often unreliable and anonymous. Hence there is a need to ensure reliable work delivery while preserving some level of privacy to the requester's data. For this purpose, we use a combination of random perturbation to mask the sensitive data and error-correcting codes for quality assurance. We also consider the possibility of collusion attacks by malicious crowd workers. We develop mathematical models to study the precise tradeoffs between task performance quality, level of privacy against collusion attacks, and cost of invoking a large crowd. Such a study provides design strategies and principles for crowd work. The use of classification codes may improve efficiency considerably. We also comment on the applicability of these techniques for scalable assessment in education via peer grading, e.g. for massive open online courses (MOOCs).
Finite element calculations of fluid menisci and thin-films in a model porous media

Abstract Finite element solutions of the augmented Young—Laplace (AYL) equation are given for a number of axisymmetric menisci that correspond to idealized solid—solid contacts in a model porous medium. The influence of the disjoining pressure on the saturation of a nonpolar wetting liquid is significant for porous media composed of particles with diameters of less than 100 μm; low interfacial tensions also cause more wetting liquid to be trapped in thin-films. A method of predicting equilibrium wetting fluid saturation in a porous medium characterized only by the porosity, a characteristic length scale, the interfacial tension between the two fluids, and the Hamaker constant of the solid—liquid—fluid system is proposed.
Effects of flow dispersers upstream of two-phase flow monitoring instruments

Abstract The effects of flow dispersing screens on the accuracy of two-phase flow monitoring instruments was studied with an air-water two-phase flow loop in which air and water flow rates were monitored separately. Flow dispersers were installed at the inlet of an instrumented spool piece containing a drag disk and a turbine meter. For the present tests, the spool piece was mounted vertically and flow was always down. When the turbine was upstream of the drag disk, two-phase mass flow rates indicated by the instruments were approximately one-third actual mass flows both in the presence and absence of flow dispersers. However, when the drag disk was upstream of the turbine, the use of flow dispersing screens upstream of the drag disk resulted in flow measurements within ± 10% of actual flow rates over the range 0–160 kg/m2· s.
The Career Planning Essay

This article describes a written exercise designed to facilitate students’ critical reflections on their career aspirations and how they can best be achieved. Students write an essay that helps the...
The stark ladder and other one-dimensional external field problems

For a certain class of analytic potentialsV(x), matrix elements of the resolvent ofH F = -d 2/dx 2 +Fx +V(x) with entire vectors of the translation group have meromorphic continuations from Imz>0 to the whole complex plane. The poles of these continuations are restricted to a discrete set independent of the analytic vectors chosen. Certain random potentials corresponding to an infinite number of particles distributed on the points of a Poisson set lie in this class with probability one as do a large class of periodic potentials.
Predicting Korean lodging firm failures: An artificial neural network model along with a logistic regression model

Abstract Using financial variables as predictors, this study developed logistic regression and artificial neural network (ANN) models to predict business failures for Korean lodging firms. While both models demonstrated comparable Type I errors, the ANN model showed considerably lower Type II errors for both in-sample and hold-out sample predictions. This study also found that interest coverage is the most important signal of business failure for the Korean hotel industry. This ratio is directly related to the hotel's solvency, ability to service debts and productivity of profits and can thus be regarded as a survival indicator of Korean hotel firms.
Pharmacokinetic optimisation of therapy with newer antidepressants.

Since the early 1950s, when imipramine was first introduced, a whole series of antidepressants with differences in structures, neurochemical effects and pharmacokinetics have been developed. Structurally or functionally, they have been classified as tricyclic antidepressants (TCAs), tetracyclic antidepressants, monoamine oxidase inhibitors (MAOIs), or selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors (SSRIs). In addition, there is a series of antidepressants with unique structures.
A radiochemical assay for a NADP+-specific γ-glutamate semialdehyde dehydrogenase extracted from mitochondrial membrane of rat intestinal epithelial cells

A radiochemical assay has been developed for a NADP+-specific gamma-glutamate semialdehyde dehydrogenase from rat intestinal epithelial cells. The spectrophotometric assay utilized to measure the enzyme in bacterial cell homogenates is not sensitive enough for homogenates from rat mitochondria, which require an assay that can measure as little as 0.5 nmol NADPH formed/min/ml extract. The assay described here is sensitive to 0.1 nmol product formed/min/ml of extract and employs the use of [3H]pyrroline 5-carboxylate which is phosphorylated and oxidized by the enzyme to gamma-[3H]glutamyl phosphate, a product that decomposes to [3H]pyrrolidone 5-carboxylate. The latter product is separated from the substrate by ion-exchange chromatography. In order to correct for any product loss during separation by ion-exchange [14C]pyrrolidone 5-carboxylate is added as an internal standard to the deproteinized assay mixture. Under the assay conditions described mammalian gamma-glutamate semialdehyde dehydrogenase activity is linear with respect to time and protein concentration. Comparison between the kinetic parameters reported for the bacterial enzyme and those reported here for the mammalian enzyme indicate similarities in the pH optima as well as a requirement for phosphate. Kinetic studies on mammalian enzyme yield apparent Km values of 1.8 mM for pyrroline 5-carboxylate, 0.2 mM for NADP+, and 11.3 mM for phosphate.
A high resolution electron microscope study of the omega transformation in ZrNb alloys

Abstract High resolution direct lattice imaging and dark field electron microscopl lere used to examine the omega phase transformation in lr-Nb allols. Direct lattice imaging demonstrated the existence of subvariants lithin an omega variant. The existence of an ordered sequence of subvariants, lhich is the basic premise of recent diffuse intensitl calculations lhich seek to explain diffuse diffraction observations in high Nb content allols, could not be checked because of the small sile of the omega regions. In the lol Nb content allols dark field electron microscopl was used to shol that the λ phase consists of large domains (100–200 A dia.) the interior of lhich contains features that are 3–6 A dia. As the Nb content is increased the omega domains decrease in sile until onll 3–5 A images are observed in allols containing 15lt.% Nb or more. The isolated images are present over the range of composition from 8 to 30lt.% Nb. Time sequence dark field micrographs shol that these small images change lith time. The diffuse λ reflections are believed due in part to the existence of a 〈111〉 linear detect, consisting of groups of 〈111〉 rols of atoms lhich are displaced from b.c.c. to λ positions for short periods of time.
Capillary electrophoresis single-strand conformation polymorphism analysis for monitoring soil bacteria

The ability to effectively monitor a microbial community is necessary to design and implement remediation strategies for contaminated soil. Single-strand conformation polymorphism (SSCP), a technique which separates DNA fragments based on their sequence, was used to analyze amplified 16S rRNA gene fragments of 12 common soil bacteria. Separation was performed using capillary electrophoresis (CE), as opposed to other common gel techniques, to eliminate the need for band analysis on gel matrices. Four different universal bacterial primer sets were used for DNA amplification: 341-534, P11-P13, Er10-Er11, and Er14-Er15 corresponding to the V3, V8, V2, and V4 regions, respectively. The forward strand of each primer was labeled with 6-carboxy fluorescein fluorescent dye. Analyses were performed on the Applied Biosystems 310 genetic analyzer using GeneScan Analysis Software version 3.5. The best results were obtained using primer 341-534, in which 6 of the 12 bacteria could be distinguished. By combining primer sets 341-534 and Er10-Er11, all 12 of the bacteria could be separated, indicating various degrees of polymorphism within the selected primer regions. When performing simultaneous amplification and analysis of all 12 species some preferential amplification occurred, as not all peaks could be observed. However, SSCP profiles obtained for pure bacterial cultures show the potential of CE-SSCP for bacterial community analysis.
Long collateral branches of substantia nigra pars reticulata axons to thalamus, superior colliculus and reticular formation in monkey and cat. Multiple retrograde neuronal labeling with fluorescent dyes

Abstract In order to gain some impressions about the degree to which individual neurons of the pars reticulata of the substantia nigra send long collateral branches to more than one of its three major targets (thalamus, superior colliculus, reticular formation), two, or all three targets were injected with fluorescent dyes (Evan's blue, granular blue, nuclear yellow, propidium iodide) in six squirrel monkeys and four cats. The best results were obtained in the monkey brain with injections of Evan's blue in the thalamus, granular blue in the colliculus and nuclear yellow in the reticular formation. Whereas nigrothalamic and nigroreticular neurons are numerous and widely scattered throughout all parts of the pars reticulata, cells projecting only to the superior colliculus are fewer in number and restricted to a rostral-lateral zone. These results are consistent with earlier data obtained with the horseradish peroxidase method. 2 Although double-labeled cells with projections to both the thalamus and reticular formation occur throughout the pars reticulata, such cells are somewhat more abundant at caudal levels of the nucleus. Cells containing dyes from both the superior colliculus and reticular formation are less common and restricted to the lateral part of the pars reticulata. A small number of cells near the rostral pole of the pars reticulata contain dye from both the tectal and thalamic injection. Typically, less than two dozen cells in any case can be confidently identified as containing all three dyes and these cells are located in the rostrolateral half of the pars reticulata. Fewer than 20% of the labeled nigral cells contain more than one dye. In the cat, thalamic injection of granular blue and tectal injection of nuclear yellow indicate that most nigrotectal cells are located in the middle of the mediolateral expanse of the pars reticulata in its rostral half. Nigrothalamic cells flank the nigrotectal group medially, laterally and caudally. Where these groups border one another, several cells contain both dyes indicating that they project to both the thalamus and colliculus. In both the cats and monkeys, a less extensive cell-labeling occurs in the contralateral nigra with a pattern similar to that in the ipsilateral substantia nigra. The results indicate that several neurons of the substantia nigra's pars reticulata send long collateral branches to two or even all three of the major targets. Many reticulata cells, however, appear to project either to the thalamus, or to the superior colliculus or to the reticular formation.
Atherosclerotic Renovascular Disease as a Cause of End-Stage Renal Disease: Cost Considerations

Atherosclerotic vascular disease affects an increasing number of patients with end-stage renal disease. A review of comorbid atherosclerotic disease in 7,200 end-stage renal disease patients indicated that occlusive disease of the renal arteries may contribute to progressive renal failure in 1.34% of the US dialysis population or in 14% of the Caucasian patients with hypertensive nephrosclerosis. The costs of dialytic care in such patients exceed USD 87 million annually. The risks and costs of surgical revascularization of such patients are large, however. These data argue that prospective trials of intervention in atherosclerotic renal artery disease are urgently needed.
Renal transport of phosphate during phosphate loading in the fresh-water turtle

The net renal transport of phosphate was measured in fresh-water turtlesChrysemys picta orC. scripta elegans before and during acute elevation of plasma phosphate by intravenous phosphate infusion. In parathyroid-intact (sham PTX) animals, net secretion or net reabsorption of phosphate could be observed during control infusions. With increasing plasma phosphate net secretion was no longer seen, and net reabsorption increased, eventually reaching a reabsorptive maximal transport rate (Tmax) of −1.5 μmoles/ml GFR at plasma concentrations of 4.0–5.0 mmoles/l. A similar pattern was observed in chronically parathyroidectomized (chronic PTX, 7–14 days) animals, but net reabsorption in this group was higher at all plasma levels, and net secretion was never observed. Tmax in chronic PTX animals was estimated at −2.0 μmoles/ml GFR. Chronic PTX animals treated with mammalian parathyroid extract (100 IU, intramuscularly, three days prior to infusion experiments) showed a reversal of the effects of PTX on net phosphate transport. Net reabsorption was reduced and net secretion was observed at both low and high plasma phosphate concentrations. These results demonstrate that net renal phosphate transport in the intact fresh-water turtle is characterized by a reabsorptive Tmax. The demonstration of net phosphate secretion in these animals requires the presence of parathyroid hormone. The secretory component of phosphate transport may be either a transepithelial flux of phosphate which is saturated at very low plasma phosphate concentrations, or a process distinct from a peritubular-to-luminal transport, and thus independent of plasma phosphate concentration.
On the inverse problem of soil profile reconstruction: a comparison of time-domain approaches

We discuss a one-dimensional inverse material profile reconstruction problem that arises in layered media underlain by a rigid bottom, when total wavefield surficial measurements are used to guide the reconstruction. To tackle the problem, we adopt the systematic framework of PDE-constrained optimization and construct an augmented misfit functional that is further endowed by a regularization scheme. We report on a comparison of spatial regularization schemes such as Tikhonov and total variation against a temporal scheme that treats the model parameters as time-dependent. We study numerically the effects of inexact initial estimates, data noise, and regularization parameter choices for all three schemes, and report inverted profiles for the modulus, and for simultaneous inversion of both the modulus and viscous damping. Our numerical experiments demonstrate comparable or superior performance of the time-dependent regularization over the Tikhonov and total variation schemes for both smooth and sharp target profiles, albeit at increased computational cost.
A note on finding a maximum empty rectangle

Abstract Given a rectangle A and a set S of n points in A , the maximum empty rectangle problem is that of finding a largest-area rectangle which is contained in A , has its sides parallel to those of A , and does not contain any of the points in S . This note describes an efficient algorithm for solving this problem.
Inhibition of drug-metabolizing enzymes in the rat after bacillus calmette-guérin treatment

Abstract Drug-metabolizing enzyme activities and protein content of hepatic microsomal preparations from adult Sprague-Dawley rats were examined at 3, 6, 10 and 14 days after intravenous, subcutaneous and intradermal administration of two different strains of Bacillus Calmette-Guerin (BCG). Pasteur liquid strain BCG, injected intravenously at 6 × 10 8 organisms/m 2 in normal saline, caused 20–45 per cent reduction of aniline hydroxylase (AH) and 5-(3,3-dimethyl-1-triazeno)imidazole-4-carboxamide demethylase (DICD) activities and the cytochrome P-450 content of microsomes from female rats but only 10–25 per cent decrease in these parameters in males. Microsomal protein content was decreased 30–40 per cent in both sexes on days 10–14. Administration of BCG by the subcutaneous route caused only 5–25 per cent impairment of AH and DICD activities in female rats, while intradermal administration of the adjuvant was without discernible effect on the rat hepatic microsomal drug-metabolizing system. The duration of pentobarbital-induced narcosis was increased up to 70 per cent in both male and female rats after intravenous administration of BCG. Tice strain lyophilized BCG at the same dose elicited similar but lesser effects. BCG added in vitro had no effect on AH and DICD activities. Livers of rats treated intravenously contained numerous granulatomous lesions throughout the parenchyma; the damage was variable and less severe in the subcutaneously treated animals. Intradermally treated rats showed normal liver histology.
Increases in vaccination coverage of healthcare personnel following institutional requirements for influenza vaccination: A national survey of US hospitals

Abstract Background Institutional requirements for influenza vaccination, ranging from policies that mandate declinations to those terminating unvaccinated healthcare personnel (HCP), are increasingly common in the US. Our objective was to determine HCP vaccine uptake following requirements for influenza vaccination at US hospitals. Methods Survey mailed in 2011 to a nationally representative sample of 998 acute care hospitals. An institutional requirement was defined as an institutional policy that requires receipt or declination of influenza vaccination, with or without consequences for vaccine refusal. Respondents reported institutional-level, seasonal influenza vaccination coverage, if known, during two consecutive influenza seasons: the season prior to (i.e., pre-requirement), and the first season of requirement (i.e., post-requirement). Weighted univariate and multivariate analyses accounted for sampling design and non-response. Results 808 (81.0%) hospitals responded. Of hospitals with institutional requirements for influenza vaccination ( n = 440), 228 hospitals met analytic inclusion criteria. Overall, mean reported institutional-level influenza vaccination coverage among HCP rose from 62.0% in the pre-requirement season to 76.6% in the post-requirement season, representing a single-season increase of 14.7 (95% CI: 12.6–16.7) percentage points. After adjusting for potential confounders, single-season increases in influenza vaccination uptake remained greater among hospitals that imposed consequences for vaccine refusal, and among hospitals with lower pre-requirement vaccination coverage. Institutional characteristics were not associated with vaccination increases of differential magnitude. Conclusion Hospitals that are unable to improve suboptimal influenza vaccination coverage through multi-faceted, voluntary vaccination campaigns may consider institutional requirements for influenza vaccination. Rapid and measurable increases in vaccination coverage followed institutional requirements at hospitals of varying demographic characteristics.
PACS bypass: a semi-automated routing solution to enable filmless operations when PACS fails.

In the filmless imaging department, an integrated imaging and reporting system is only as strong as its weakest link. An outage or downtime of a key segment, such as the Picture Archive Communications System (PACS), is a significant threat to efficient workflow, quality of image interpretation, ordering clinician’s review, and ultimately patient care. A multidisciplinary team (including physicists, technologists, radiologists, operations, and IT) developed a backup system to provide business continuity (i.e., quality control, interpretation, reporting, and clinician access) during an extended outage of the main departmental PACS.
Network reliability: the effect of local network structure on diffusive processes.

This paper reintroduces the network reliability polynomial, introduced by Moore and Shannon [Moore and Shannon, J. Franklin Inst. 262, 191 (1956)], for studying the effect of network structure on the spread of diseases. We exhibit a representation of the polynomial that is well suited for estimation by distributed simulation. We describe a collection of graphs derived from Erdős-Renyi and scale-free-like random graphs in which we have manipulated assortativity-by-degree and the number of triangles. We evaluate the network reliability for all of these graphs under a reliability rule that is related to the expected size of a connected component. Through these extensive simulations, we show that for positively or neutrally assortative graphs, swapping edges to increase the number of triangles does not increase the network reliability. Also, positively assortative graphs are more reliable than neutral or disassortative graphs with the same number of edges. Moreover, we show the combined effect of both assortativity-by-degree and the presence of triangles on the critical point and the size of the smallest subgraph that is reliable.
Egocentric Bias in Estimates of Consensus

Summary This study compared the preceptual distortion and motivational explanations of egocentric bias in estimates of consensus. Ss were contestants in the television game show “Play the Percentages.” This nonlaboratory situation offered compelling incentives (thousands of dollars in cash and prizes) for accurate estimates of consensus. It was reasoned that if Ss had accurate estimates of consensus at their disposal, they would have utilized them to obtain the incentives. Nonetheless, previously observed egocentric biases (false consensus and the minority's overestimation of consensus) were found. These results indicated that an egocentric bias in estimates of consensus was more likely a result of perceptual distortion than of motivational strategies.
A simple climatological model of the dynamics and energetics of the nocturnal circulation at Lake Victoria

The local atmospheric night-time circulation at Lake Victoria (East Africa) is simulated by a simple model which is cylindrically symmetric. It consists of an upper layer (linearized, steady state, hydrostatic, incompressible, saturated over the lake) above a surface boundary layer (constant flux layer, log + lin profile). Analytical solutions are derived for the dynamical, energetical, and hydrological parameters. They mainly depend on the surface temperature difference between land and lake, which is the driving mechanism of the motion, and the choice of representative mesoscale transport coefficients Km, Kh. The results are compared with the climatological features of the nocturnal circulation.
An analysis of interface cracks between dissimilar isotropic materials using conservation integrals in elasticity

Abstract A new method of analysis is presented for studying the mixed-mode interface crack between dissimilar isotropic materials. The method of approach is formulated on the basis of recently developed conservation laws in elasticity for nonhomogeneous solids and fundamental relationships in fracture mechanics of interface cracks. A solution procedure for the analysis is established and shown to be computationally efficient and operationally simple, involving only known auxiliary solutions and evaluation of conservation integrals along a path removed from the crack tip. An important feature of the present approach is that the crack-tip stress intensity factor solution for each individual fracture mode can be determined accurately and -conveniently by information extracted in the far field. Numerical examples, whose solutions are available in the literature, are presented to demonstrate the accuracy, convergence, and related characteristics of the current approach.
Temporal patterns of head and neck squamous cell carcinoma recurrence with positron-emission tomography/computed tomography monitoring.

Objectives/Hypothesis To estimate the distribution of head and neck squamous cell carcinoma (HNSCC) recurrence after definitive chemoradiation therapy (CRT) among patients who underwent 18F-fluorodeoxyglucose positron-emission tomography and computed tomography (PET/CT) surveillance.
Triple arthrodesis for children with spastic cerebral palsy

A retrospective review was done of 20 children with spastic cerebral palsy who had had a total of 25 triple arthrodeses at Rancho Los Amigos Hospital. The average age at the time of surgery was 15.5 years and average follow-up was 4.5 years. Indications for surgery were progressive deformity (15) and relief of pain (five). The deformities was planovalgus (12), equinovalgus (six), equinovarus (six) and calcaneovalgus (one). All 13 patients with braces had problems in wearing them. Two patients were non-ambulatory preoperatively and remained so after fusion. Of the 18 who were ambulatory preoperatively, 15 remained so and there was no change in the type of ambulation: the other three stopped ambulating. Three children were made independent of braces. It is concluded that triple arthrodesis is an excellent procedure for children with spastic cerebral palsy, to correct deformity and relieve pain, but it should be done while the children are still walking for the best chances of continued ambulation.
Seasonality in birth defects, agricultural production and urban location.

Abstract This paper tests whether the strength of the “spring spike” in birth defects is related to agricultural production and urban location using Texas Birth Defects Registry data for the period 1996–2007. We find evidence of a spike in birth defects among children conceived in the spring and summer, but it is more pronounced in urban non-agricultural counties than in other types of counties. Furthermore, the spike lasts longer in urban non-agricultural counties as compared to other types of counties.
Sudden death among infants and adults: companion disorders of maladaptive sympathetic bias

Sudden infant death syndrome is the leading cause of death in infancy, but its pathophysiological mechanism has been elusive. Sudden death in adults is a common phenomenon, but the etiology in many cases remains unknown at autopsy. We hypothesize that maladaptive sympathetic bias is the explanatory mechanism that links many cases of sudden demise among adults and infants as companion syndromes. Normally, sympathetic response occurs as an adaptation to physiologic demands of the body through various autonomic reflex arcs such as chemoreceptors. Sympathetic response can become chronic and maladaptive when the normal sympathetic response fails to correct the precipitating physiologic trigger, leading to chronic activation of autonomic reflex arcs. In conditions such as infant sleep apnea or adult heart failure, a pernicious cycle of sympathetic bias may result. Chronic sympathetic bias increases susceptibility to sudden fatal arrhythmias, QT-related and otherwise, in the setting of an exaggerated adrenergic challenge. Examples of such adrenergic stressors include trauma, hypoxia, hypercapnia, acidosis, sleep arousal, illness, medical procedures, and physical activity, all of which have associations with sudden death. Our hypothesis may not only help explain the survival benefits of drugs such as beta-blockers and devices such as synchronization therapy, but also portend new application of similar therapies for many conditions of sympathetic bias.
INTERNET-BASED INFORMATION ON ALCOHOL, TOBACCO, AND OTHER DRUGS: ISSUES OF ETHICS, QUALITY, AND ACCOUNTABILITY

This article discusses ethical and quality issues involved in accessing and evaluating Internet-based information on alcohol, tobacco, and other drugs (ATODs). After a brief overview of the World Wide Web and its potential for increasing knowledge in the fields of ATOD prevention, treatment, research, and policy, we discuss potential threats that may compromise the quality and utilization of Web-based ATOD information. Consumers and authors of Web-based materials must critically assess and evaluate that information; the Information Quality Tool developed by the Health Summit Working Group is suggested as an analytic framework useful in evaluating ATOD information. The article concludes with observations about future issues regarding dissemination of ATOD information on the Internet.
Effects of Air Traffic Geometry on Pilots' Conflict Detection With Cockpit Display of Traffic Information

OBJECTIVE: This experiment attempted to identify the features of air traffic geometry that would influence the difficulty and biases of pilots' conflict detection using a cockpit display of traffic information (CDTI). BACKGROUND: There was previously no systematic study on effects of such features on conflict detection using the CDTI. METHOD: Twenty-four pilots viewed dynamic encounters between their own aircraft and an intruder aircraft on a simulated CDTI; difficulty was varied by the intruder aircraft's distance and time to closest point of approach (CPA), relative speed, miss distance at CPA, approach side, and conflict angle. Participants estimated the intruder's location at, and its time to, CPA. Effects on three estimation error measures were explored: intruder's miss distance at CPA, orientation at CPA, and time to CPA. RESULTS: (a) Estimation errors increased with slower speeds, longer times to CPA, and longer distances to CPA and with longer miss distances at CPA; (b) the best performance occurred at a conflict angle of 90 degrees; (c) there was a bias to judge conflicts to be more risky than was actually the case; and (d) there was a "distance-over-speed" bias, such that two aircraft farther apart and converging rapidly were perceived as less risky than when they were closer to each other and converging at a slower rate, despite identical time to CPA. CONCLUSION: Pilots' conflict detection with CDTI was subject to various errors and biases, which has important safety implications. APPLICATION: The design of procedures, displays, and decision support tools for the free flight environment needs to take these human performance limitations into account. Language: en
Common mode current reduction in an inverter-fed induction motor control system

This paper presents a novel control method to separate the inverter switching pattern optimization from induction motor's torque and flux control. The optimization is defined in terms of common mode current reduction. The motor control is based on the calculation of desired phase currents with given torque and flux references. The common mode current reduction is achieved by neutral point voltage control using sliding mode pulse width modulation. Common mode current is eliminated without modifying the six-switch inverter.
Local Photorelease of Caged Thymosin β4 in Locomoting Keratocytes Causes Cell Turning

The broad aim of this work was to explore the feasibility of using light-directed perturbation techniques to study cell locomotion. Specifically, a caged form of thymosin beta4 (Tbeta4) was photoactivated in a defined local region of locomoting fish scale keratocytes and the resulting perturbation of locomotion was studied. Purified Tbeta4 was produced in an inactive form by "caging" with ([n-nitroveratryl]oxy)chlorocarbamate. In vitro spectrophotofluorometric assays indicated that caged Tbeta4 did not change the normal actin polymerization kinetics, whereas photoactivated Tbeta4 significantly inhibited actin polymerization. With an a priori knowledge of the cytoplasmic diffusion coefficient of Tbeta4 as measured by fluorescence recovery after photobleaching experiments, the rapid sequestration of actin monomers by uncaged Tbeta4 and the consequent reduction in the diffusional spread of the Tbeta4-actin complex were predicted using Virtual Cell software (developed at the Center for Biomedical Imaging Technology, University of Connecticut Health Center). These simulations demonstrated that locally photoactivating Tbeta4 in keratocytes could potentially elicit a regional locomotory response. Indeed, when caged Tbeta4 was locally photoactivated at the wings of locomoting keratocytes, specific turning about the irradiated region was observed, whereas various controls were negative. Additionally, loading of exogenous Tbeta4 into both keratocytes and fibroblasts caused very rapid disassembly of actin filaments and reduction of cellular contractility. Based on these results, a mechanical model is proposed for the turning behavior of keratocytes in response to photoreleased Tbeta4.
Potato Cultivar Response to Seasonal Drought Patterns

The ability to minimize potato yield and quality losses due to drought can be greatly improved by understanding the relative responses of different cultivars to seasonal variations in water supply. To address this need, we initiated a 2 year field experiment to determine the responses of the six potato cultivars to different seasonal drought patterns, including 1) full season irrigation at 100 % ET, 2) irrigation at 100 % ET terminated during late bulking , 3) full season irrigation at 70 % ET , 4) irrigation at 70 % ET terminated during late bulking , and 5) a gradual reduction in irrigation from 100 % ET during tuber initiation through early bulking, to 70 % ET during mid-bulking, and 50 % ET through late bulking. GemStar Russet and Ranger Russet, two medium-late maturing cultivars, generally produced the highest yields across the range of drought treatments, but both were fairly sensitive to changes in drought severity. Alturas, a late maturing cultivar, produced relatively high yields with full irrigation, but exhibited the greatest sensitivity to increasing drought severity, particularly when severe late-season water deficits were imposed. Yields for the early maturing cultivar Russet Norkotah were relatively low overall, but it was the least sensitive to changes in drought severity, particularly when late season drought was imposed. Russet Burbank produced comparatively high total yields across the range of drought treatments, but U.S. No. 1 yields were substantially reduced by each seasonal drought pattern. However, it was less sensitive to changes in drought severity than GemStar Russet, Ranger Russet and Alturas. Total and U.S. No. 1 yields for Summit Russet were low for each drought treatment and it exhibited intermediate sensitivity to changes in drought severity. GemStar Russet had the highest water use efficiency based on U.S. No. 1 yield.
Regulation of DNA replication during development

As development unfolds, DNA replication is not only coordinated with cell proliferation, but is regulated uniquely in specific cell types and organs. This differential regulation of DNA synthesis requires crosstalk between DNA replication and differentiation. This dynamic aspect of DNA replication is highlighted by the finding that the distribution of replication origins varies between differentiated cell types and changes with differentiation. Moreover, differential DNA replication in some cell types can lead to increases or decreases in gene copy number along chromosomes. This review highlights the recent advances and technologies that have provided us with new insights into the developmental regulation of DNA replication.
Limited efficacy of intensified preparative regimens and autologous transplantation as salvage therapy in high grade non-Hodgkin's lymphoma.

Between 9/86 and 6/98, 22 patients with relapsed or refractory high grade lymphoma received intensified preparative therapy and underwent autologous transplantation at a single institution. Two intensified preparative regimens were used--cyclophosphamide, etoposide, total body irradiation (CY-VP-TBI) (N=17) and cyclophosphamide, BCNU, etoposide (CBV) (N=5). For all patients undergoing autologous transplantation, 5 year actuarial survival (S) and 5 year event free survival (EFS) were only 18% +/- 8%. Treatment related mortality was 14% overall but only 8% in patients receiving G-CSF or GM-CSF. Survival was significantly inferior to the survival observed in a concurrent series of patients with intermediate grade lymphoma, 34% +/- 6%, p < .05. Using high dose therapy in conjunction with autologous transplantation at the time of relapse may not be as valuable a strategy in high-grade lymphoma as in intermediate grade lymphoma although most studies combine the two disorders. Alternative strategies for the use of transplantation in high grade lymphoma, such as the use of transplantation as consolidation therapy, need to be investigated.
Intellectuals’ Political Orientations: Toward an Analytical Sociology

This article surveys the field of the sociology of intellectuals, and calls for a move toward an analytical sociology. The topics covered include the definitions of intellectuals, the debates on whether intellectuals constitute a universal class, and the role of intellectuals in the society, in particular intellectuals’ involvement in politics. The article then moves on to the literature on intellectuals’ political consciousness, and makes a call for a shift from a moralistic mission to an analytical approach, while suggesting a shift of the intellectual from an “independent variable” to a “dependent variable.”
Application-specific memory management for embedded systems using software-controlled caches

We propose a way to improve the performance of embedded processors running data-intensive applications by allowing software to allocate on-chip memory on an application-specific basis. On-chip memory in the form of cache can be made to act like scratch-pad memory via a novel hardware mechanism, which we call column caching. Column caching enables dynamic cache partitioning in software, by mapping data regions to a specified sets of cache “columns” or “ways.” When a region of memory is exclusively mapped to an equivalent sized partition of cache, column caching provides the same functionality and predictability as a dedicated scratchpad memory for time-critical parts of a real-time application. The ratio between scratchpad size and cache size can be easily and quickly varied for each application, or each task within an application. Thus, software has much finer software control of on-chip memory, providing the ability to dynamically tradeoff performance for on-chip memory.
Interspecific egg rejection as ecological collateral damage from selection driven by conspecific brood parasitism

Distinguishing between interspecific and intraspecific coevolution as the selective driver of traits can be difficult in some taxa. A previous study of an avian obligate brood parasite, the black-headed duck, Heteronetta atricapilla, suggested that egg rejection by its two main hosts (two species of coot) is an incidental by-product of selection from conspecific brood parasitism within the hosts, not selection imposed by the interspecific parasite. However, although both species of coot can recognize and reject eggs of conspecific brood parasites, which closely resemble their own, they paradoxically also accept a moderate fraction of duck eggs (40e60%), which differ strikingly in shape and colour from their own eggs. Here we test the key assumption of the incidental by-product hypothesis that natural selection for egg recognition solely from conspecific brood parasitism can result in intermediate levels of rejection of nonmimetic eggs. We repeated the same egg rejection experiments conducted previously with the two Argentine hosts in a third closely related species that experiences only conspecific brood parasitism, the American coot, Fulica americana. These experiments yielded the same intermediate rejection rates for nonmimetic duck eggs. Our results confirm that selection from conspecific brood parasitism can lead to counterintuitive intermediate rejection rates of nonmimetic interspecific eggs and further support the suggestion that selection from antagonism within species can incidentally affect interactions between species.
Functional Neuroanatomy of Auditory Working Memory in Schizophrenia: Relation to Positive and Negative Symptoms

Functional brain imaging studies of working memory (WM) in schizophrenia have yielded inconsistent results regarding deficits in the dorsolateral prefrontal (DLPFC) and parietal cortices. In spite of its potential importance in schizophrenia, there have been few investigations of WM deficits using auditory stimuli and no functional imaging studies have attempted to relate brain activation during auditory WM to positive and negative symptoms of schizophrenia. We used a two-back auditory WM paradigm in a functional MRI study of men with schizophrenia (N = 11) and controls (N = 13). Region of interest analysis was used to investigate group differences in activation as well as correlations with symptom scores from the Brief Psychiatric Rating Scale. Patients with schizophrenia performed significantly worse and were slower than control subjects in the WM task. Patients also showed decreased lateralization of activation and significant WM related activation deficits in the left and right DLPFC, frontal operculum, inferior parietal, and superior parietal cortex but not in the anterior cingulate or superior temporal gyrus. These results indicate that in addition to the prefrontal cortex, parietal cortex function is also disrupted during WM in schizophrenia. Withdrawal-retardation symptom scores were inversely correlated with frontal operculum activation. Thinking disturbance symptom scores were inversely correlated with right DLPFC activation. Our findings suggest an association between thinking disturbance symptoms, particularly unusual thought content, and disrupted WM processing in schizophrenia.
Polymer lateral diffusion at the solid-liquid interface.

Measurements are presented of how polymer surface diffusion at the solid−liquid interface is controlled by surface coverage. The method of measurement was fluorescence correlation spectroscopy (FCS), and the system was poly(ethylene oxide) (PEG) adsorbed onto methyl-terminated self-assembled monolayers in buffered aqueous solution. The translational diffusion coefficient at first increased with increasing surface concentration, presumably because the number of adsorption sites per molecule decreased. Ultimately it slowed by 1 order of magnitude, presumably reflecting jamming by neighboring chains.
Conditional effects in Graphplan

Graphplan has attracted considerable interest because of its extremely high performance, but the algorithm's inability to handle action representations more expressive than STRIPS is a major limitation. In particular, extending Graphplan to handle conditional effects is a surprisingly subtle enterprise. In this paper, we describe the space of possible alternatives, and then concentrate on one particular approach we call factored expansion. Factored expansion splits an action with conditional effects into several new actions called components, one for each conditional effect. Because these action components are not independent, factored expansion complicates both the mutual exclusion and backward chaining phases of Graphplan. As compensation, factored expansion often produces dramatically smaller domain models than does the more obvious full-expansion into exclusive STRIPS actions. We present experimental results showing that factored expansion dominates full expansion on large problems.