cssi/SciSciGPT-SciSciNet huggingface dataset:
Past experience, recency, and spontaneous recovery in choice behavior

Pigeons’ responses on two keys were recorded before and after the percentage of reinforcers delivered by each key was changed. In each condition of Experiment 1, the reinforcement percentage for one key was 50% for several sessions, then either 70% or 90% for one, two, or three sessions, and then 50% for another few sessions. At the start of the second and third sessions after a change in reinforcement percentages, choice percentages often exhibited spontaneous recovery—a reversion to the response percentages of earlier sessions. The spontaneous recovery consisted of a shift toward a more extreme response percentage in some cases and toward a less extreme response percentage in other cases, depending on what reinforcement percentages were previously in effect. In Experiment 2, some conditions included a 3-day rest period before a change in reinforcement percentages, and other conditions included no such rest days. Slightly less spontaneous recovery was observed in conditions with the rest periods, suggesting that the influence of prior sessions diminished with the passage of time. The results are consistent with the view that choice behavior at the start of a new session is based on a weighted average of the events of the past several sessions.
Role Making among Married Mexican American Women: Issues of Class and Ethnicity

This article discusses how married Mexican American women are redefining their roles and conjugal relationships. Employing a symbolic interactionist framework, the author held in-depth interviews with 75 Mexican American couples in Austin and Corpus Christi, Texas, and conducted participant observation of many others. The data indicate that contrary to previous reports, married women are not passive, but have actually taken the lead in role making. The working-class women studied were seeking separate identities from their husbands, something the business/professional women had already attained. The women experienced strain from the changes in their lives, and faced discrimination based on both their gender and ethnicity. The author calls for recognition of the diversity among families in minority groups, of the resistance to change minority-group women face by being "twice a minority," and of the need to examine organizational structures not only from management's perspective, but also from that of the s...
Parasitoid guilds: defining the structure of the parasitoid communities of endopterygote insect hosts

Parasitoids constitute an important component of the biodiversity of terrestrial ecosystems and have become a recent focus for investigations of pattern and process in ecological communities. This article uses parasitoid guilds to characterize the structure of parasitoid communities associated with endopterygote hosts. Parasitoid guilds are defined by three parameters, the host stage attacked, the host stage killed, and the mode of parasitism (internal or external development). A series of 12 guilds are recognized from the patterns of host exploitation by parasitoids; one that utilizes the host egg stage as a resource for parasitoid development, three that utilize the host larva, four that utilize the host prepupa, two that utilize the host pupa, and two that utilize the host adult. A comparison of the parasitoid guilds across endopterygote host orders illustrates the taxonomic diversity of parasitoids in each guild and provides an indication of some of the more frequent parasitoid taxa associated with each guild. The value of the parasitoid guild as an ecological unit that both classifies the functional ecology of parasitoid species and the structure of parasitoid communities is discussed.
COMMENT ON “FLUENCY AS A PERVASIVE ELEMENT IN THE MEASUREMENT OF CREATIVITY”

Clark and Mirels reported a "correction procedure" for fluency in scoring figural divergent thinking measures, which resulted in a reduction from .40 to .20 in the average intercorrelation of scores excluding fluency. Since their correction involved shortening the test, at least part of the reduction of the intercorrelations can be explained by the reduced reliability of the test. Estimates of the magnitude of this effect were provided. It was concluded that the "correction" reported is at best a partial correction, and that the potential merit of other procedures should be considered. Clark and Mirels (1970, p. 84) suggested ". . where high correlations are found among indices of creativity, the size of these correlations is frequently attributable to fluency, which influences all scores." Through a scoring procedure which "corrected" for fluency, they reported that intercorrelations among several measures from the Figure Completion subtest of the Minnesota Tests of Creative Thinking (Torrance, 1962) were decreased. Their procedure consisted of administering a modified form of the subtest to 93 students. These were then scored according to the instructions provided in the manual (Yamamoto, 1964). Five scores: fluency, flexibility, originality, elaboration, and title adequacy were derived. The modified procedure consisted of scoring only the first three responses of each student for the latter four measures. (It should be noted that the original Figure Completion subtest consisted of six figures.) Clark and Mirels reported a mean intercorrelation among "uncorrected" subtest scores of .45, and a mean intercorrelation for the "corrected" measures of .08 including fluency and .20 excluding fluency. And from communication with the authors1 it was found that the mean intercorrelations for "uncorrected" subtest scores excluding fluency was .40. They attributed this change to the partialing out of the effect of fluency from the other four measures. Since all items in the Figure Completion subtest can be considered equivalent in scoring, the "correction" procedure is a simple shortening of the test from six to three items. This suggests that one might apply the formula (Gulliksen, 1950) for the change in a validity coefficient as a function of the change in length of test and test reliability. r12= ~~r12
Contact line characteristics of liquid–gas interfaces over grooved surfaces

Surface wetting is an important phenomenon in many industrial processes including micro- and nanofluidics. The wetting characteristics depend on the surface tension forces at the three-phase contact line and can be altered by introducing patterned groove structures. This study investigates the effect of the grooves on the transition in the wetting behavior between the Cassie to Wenzel regimes. The experiments demonstrate that the wettability on a patterned surface depends on the spacing factor (S = channel depth/channel width). The spacing factor influences the contact angle, contact angle hysteresis, and the transition characteristics between the Cassie and Wenzel states. It was noted that under certain conditions (S > 1) the droplet behaved as a Cassie droplet, while exhibiting Wenzel wetting the rest of the time on the silicon microchannels tested. This criterion was used to design the groove structures on the sidewall of the proton exchange membrane fuel cell gas channel to remove the water effectively. The water coming from the land region into the gas channel is pulled by the grooves to the top wall where the airflow aided in its removal. Also, the contact angles measured on the surfaces were compared with the classical models that use wetted area, and the contact line model that uses the three-phase contact line length. It was found in our experiments that the contact line model predicts the contact angle on the patterned groove surfaces more accurately than the classical models.
Errors in Infrared Thermometry and Radiometry

Abstract This paper describes an error apparently unrecognized among atmospheric scientists engaged in infrared thermometry and radiometry. The error results from multiple reflections between the target environment viewed by a thermometer or radiometer and the background environment. The difference between the sum of this error and other known errors, on the one hand, and only the other known errors, on the other hand, is termed the “unrecognized error.” Its magnitude and sign are analyzed with respect to the ratio of the background and target temperatures and with respect to the emissivities of the target and the background. The error for thermometry increases as either the target or the background departs from the blackbody condition, and as the background becomes warmer relative to the target. Analogous errors for radiometry are examined with the same results.
Fiscal policy, the current account and the external debt problem in the Dominican Republic

Although the Dominican Republic had one of the highest economic growth rates in the world between 1969 and 1973, its growth performance and external position deteriorated sharply in the 1970s. By 1985 it had an external debt/GDP ratio of 76.6%, well above the average of 62.3 % for the Latin American and Caribbean region as a whole.1 The Dominican debt crisis that emerged in the I98os, like the crisis in many other debtridden Less Developed Countries (LDCs), was in part caused by adverse external conditions; in part, however, it was the result of domestic policy choices. Among the latter, large fiscal imbalances are arguably the most important.2 This article provides a case study of the link between budgetary and external disequilibria in the Dominican Republic (DR). The analysis starts with a brief description of the worsening external imbalances of the last decade and then proceeds to identify the multiple factors that, in our view, were responsible for this unsatisfactory performance. The discussion focuses on underlying macroeconomic trends and especially on macro policy decisions that contributed to the debt build-up. As we emphasise, however, the analysis of the major determinants of public sector saving, investment, and external borrowing decisions in the last quarter century of Dominican history goes beyond a simple description of aggregate economic performance. The set of politically and economically feasible policies has been severely limited by the country's political and social structure the legacy of the thirty year (I93 o-6 I) dictatorship of Rafael L.
STUDIES ON THE SENSITIZATION OF ANIMALS WITH SIMPLE CHEMICAL COMPOUNDS : V. SENSITIZATION TO DIAZOMETHANE AND MUSTARD OIL.

With the view of making new types of chemicals accessible for investigations on drug hypersensitiveness, methods have been devised for sensitizing animals with diazomethane and mustard oil, two non-aromatic compounds. Guinea pigs have been sensitized to diazomethane, a substance of high reactivity and known to cause severe allergic effects in man. With the second substance, allylisothiocyanate, likewise capable of forming conjugates with substances in the animal body, sensitization effects have been obtained in man and in hogs. Sensitization in human beings was successful with one out of six individuals treated. The observations indicate species and individual differences as regards the ability to become sensitized to various chemical compounds.
Aluminum Contact Surfaces in Electrical Transition Interfaces

The resistance of certain electrical transition interfaces involving plane, nonplated aluminum contact surfaces increases with service. Analysis of resistance characteristics indicates formation of the contact interface during connection installation produces systematic disruption of the surface film. Interfacial shear strain -- relative movement--between the contact members is identified as the efficient cause of the increase in resistance. If the selected combination of contact surfaces and members for an application does not assure adequate interfacial fixity, the introduction of a shear component of contact force--parallel to the plane representing the interface--may destroy or, if destroyed, may reestablish elemental electric contacts, depending upon the orientation of the shear component. Test data include contact resistances of interfaces involving Al and Cu conductors as well as Ag, Cd, Ni, and Sn platings.
Mutagenic activity and specificity of N-nitrosomethylaniline and N-nitrosodiphenylamine in Salmonella

Abstract The carcinogenic nitrosamines, N -nitrosomethylaniline (NMA) and N -nitrosodiphenylamine (NDphA), which have been previously reported negative or very weakly mutagenic in the Salmonella/microsome assay, were found to be mutagenic in the hisG428 Salmonella strain, TA104. NMA was moderately potent and NDphA was about 10% as potent. Mutagenesis by both compounds was dependent on the uvrB mutation and enhanced in strains harboring the plasmid, pKM101. The mutational specificities of NMA and NDphA for base-pair substitutions were determined by assaying their activities in several mutants which are reverted by a limited number, or a single type of base-pair substitution mutation, and additionally by subclassification of revertants. NMA induced predominantly AT → CG transversions and NDphA induced AT → TA transversions. The specificity of NMA and NDphA for mutagenesis at AT base pairs and the lack of sensitivity of the previously employed hisG46 strains for these base changes may be the reason for the previous reports on the lack of mutagenic activity of these compounds. This specificity is quite unusual for nitrosamines and is consitent with the hypothesis that NMA and NDphA lead to DNA damage of different nature than that produced by other nitrosamines.
A fading procedure facilitates the maintenance of observing responses when the more valued stimulus is not produced

Pigeons served in two experiments in which responding on an observing key converted a two-component mixed schedule to the corresponding multiple schedule of reinforcement. Presentation of the stimulus correlated with the more valued component was faded out (probabilistically) over sessions, so that ultimately an observing response produced only the stimulus correlated with the less valued component. Observing was well maintained after a fading procedure when a stimulus was produced by a single response, regardless of whether the less valued stimulus was associated with food or with extinction (Experiment 1). However, observing was not well maintained after a fading procedure when a stimulus was produced according to an intermittent schedule (Experiment 2). Taken together, the results of the two experiments suggest that the absence of an exteroceptive stimulus change after a single response may become discriminative in its own right for the more valued component, and that the fading procedure is an effective means of promoting this discrimination. However, if observing responses produce a stimulus change according to an intermittent schedule, then the absence of a stimulus change after a response is correlated with both components. Under these conditions, the absence of stimulus change is not discriminative for either component, even with fading, and observing is not maintained.
The Risk of a Mosquito-Borne Infectionin a Heterogeneous Environment

A common assumption about malaria, dengue, and other mosquito-borne infections is that the two main components of the risk of human infection—the rate at which people are bitten (human biting rate) and the proportion of mosquitoes that are infectious—are positively correlated. In fact, these two risk factors are generated by different processes and may be negatively correlated across space and time in heterogeneous environments. Uneven distribution of blood-meal hosts and larval habitat creates a spatial mosaic of demograPhic sources and sinks. Moreover, mosquito populations fluctuate temporally, forced by environmental variables such as rainfall, temperature, and humidity. These sources of spatial and temporal heterogeneity in the distribution of mosquito populations generate variability in the human biting rate, in the proportion of mosquitoes that are infectious, and in the risk of human infection. To understand how heterogeneity affects the epidemiology of mosquito-borne infections, we developed a set of simple models that incorporate heterogeneity in a stepwise fashion. These models predict that the human biting rate is highest shortly after the mosquito densities peak, near breeding sites where adult mosquitoes emerge, and around the edges of areas where humans are aggregated. In contrast, the proportion of mosquitoes that are infectious reflects the age structure of mosquito populations; it peaks where old mosquitoes are found, far from mosquito breeding habitat, and when mosquito population density is declining. Finally, we show that estimates for the average risk of infection that are based on the average entomological inoculation rate are strongly biased in heterogeneous environments.
DNA as a molecular wire

Abstract Physical mechanisms that might assure the functioning of DNA as a molecular wire are considered on the basis of recent progress in understanding long-range charge transfer in this biologically important molecule. Our analysis shows that DNA behaves as an insulator at low bias, while beyond the threshold the current sharply increases. Such behaviour concurs with recent experimental observations and is explained by the decrease of the energy gap between the HOMO of guanine bases and the Fermi level of the contact with the voltage applied across the individual DNA molecule. We propose a model for the hole injection in DNA, which is based on the dynamic control of this process by internal motions of base pairs in the stack. The temperature dependence of the voltage gap obtained within this model is found to be in reasonable agreement with the available experimental data. For systems, where charge transfer is controlled by changes in the relative orientation of the donor and acceptor and where the equilibrium states are optimally overlapped, the model predicts the decrease of the tunneling transfer rate with temperature. We also demonstrate that depending on the structure of the stack, hole transport along DNA wires above the voltage threshold can proceed via two different mechanisms. In the case of duplex DNA oligomers with stacked adenine–thymine and guanine–cytosine pairs migration of injected holes can be viewed as a series of short-range hops between energetically appropriate guanine bases. By contrast, in double-stranded poly(guanine)–poly(cytosine) the band-like motion of holes through bases dominates.
Quantum gravity on a laptop: 1 + 1 Dimensional Causal Dynamical Triangulation simulation

Abstract The quest for quantum gravity has been long and difficult. Causal Dynamical Triangulation is a new and straightforward approach to quantum gravity that recovers classical spacetime at large scales by enforcing causality at small scales. CDT combines quantum physics with general relativity in a Feynman sum-over-geometries and converts the sum into a discrete statistical physics problem. We solve this problem using a new Monte Carlo simulation to compute the spatial fluctuations of an empty universe with one space and one time dimensions. Our results compare favorably with theory and provide an accessible but detailed introduction to quantum gravity via a simulation that runs on a laptop computer.
The temperature distribution in an infinite medium resulting from a plane source of finite duration

The temperature distribution in an infinite slab during and following heat generation by a plane source of finite duration is studied. An expression for the instantaneous plane source is obtained. By integration of this expression, the temperature distribution following the end of heating can be obtained. Further, the treatment is extended to time-varying heat generation functions, and an example is presented.
Stark mixing of 2S muonic helium. I. Collisions with hydrogen atoms

The transitions between the 2S and 2P states of the muonic helium atom (\ensuremath{\alpha}\ensuremath{\mu} or $^{3}\mathit{\ensuremath{\mu}}$) in collisions with hydrogen atoms are examined using the rectilinear-trajectory coupled-equation method. The 2S level shift is included semiempirically and the target atom is approximated using the frozen ground-state charge density. Partial decoupling of the coupled equations is achieved, and some simple approximations for the 2S-to-2P transition probability are derived and compared with the exact solution of the coupled equations. The cross section obtained is fit by ${\ensuremath{\sigma}}_{2S\mathrm{\ensuremath{-}}2P}$\ensuremath{\simeq}5.5\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}3}$/ ${v}^{1.8}$${a}_{0}^{2}$ for v\ensuremath{\gtrsim}1, with the velocity v in atomic units, and muon-catalyzed fusion parameters are reevaluated using this expression.
The timing of activity in motor neurons that produce radula movements distinguishes ingestion from rejection in Aplysia

1. We have studied the neural circuitry mediating ingestion and rejection in Aplysia using a reduced preparation that produces ingestion-like and rejection-like motor patterns in response to physiological stimuli. 2. We have characterized 3 buccal ganglion motor neurons that produce specific movements of the radula and buccal mass. B8a and B8b act to close the radula. B10 acts to close the jaws and retract the radula. 3. The patterns of activity in these neurons can be used to distinguish the ingestion-like and rejection-like motor patterns. B8a, B8b and B10 are active together during the ingestion-like pattern. Activity in B8a and B8b ends prior to the onset of activity in B10 during the rejection-like pattern. 4. Our data suggest that these neurons undergo similar patterns of activity in vivo. During both feeding-like patterns, the activity and peripheral actions of B8a, B8b, and B10 are consistent with radula movements observed during ingestion and rejection. In addition, the extracellular activity produced by these neurons is consistent with neural activity observed in vivo during ingestion and rejection. 5. Our data suggest that the different activity patterns observed in these motor neurons contribute to the different radula movements that distinguish ingestion from rejection.
A Simulation Approach to Evaluate the Time Cost of Parallel Computations

In this paper, the execution time cost of a parallel computation in a shared memory environment is defined as a function of the input, the algorithm, the data structure, the processor speed, the number of processors, the processing power allocation and the communication between processors. The computation structure model is modified to describe the impact of these seven factors on the computation's execution time cost. A simulation technique is developed to analyze and evaluate the computation's execution time. A software tool, TCSS (Time Cost Simulation System) that implements the simulation technique is also described.
Efficacy of POST herbicides on weeds during compensatory growth

Abstract Death of the apical shoot and subsequent compensatory growth from previously inhibited axillary buds is a possible result of POST weed control practices. The objective of this research was to determine the efficacy of glyphosate and lactofen on ivyleaf morningglory, common waterhemp, and giant ragweed during mechanically stimulated compensatory growth. Plants were grown in the greenhouse to a height (or lateral growth) of 15 cm; at which time, the apical shoots were removed by cutting just above the cotyledonary node. Plants were allowed to regrow to 15 cm and treated with lactofen or glyphosate. Herbicide treatments were also applied to intact plants that were 15 cm in height for comparison. Weed response to herbicides during mechanically stimulated compensatory growth varied by weed species and herbicide. Giant ragweed under compensatory growth was less sensitive to both glyphosate and lactofen compared with intact plants. Comparison of GR50 (the herbicide dose that reduced dry weight by 50%) v...
Distribution of protons and Cd between bacterial surfaces and dissolved humic substances determined through chemical equilibrium modeling

Bacteria and dissolved humic substances are capable of binding significant concentrations of metals in natural environments. Recent advances in understanding bacteria-metal and humic-metal complex- ation have provided a framework for directly comparing the binding capacities of these components. In this study, we use chemical equilibrium modeling to construct an internally consistent set of thermodynamic equilibrium constants for proton and Cd binding onto dissolved humic substances, using a variety of published data sets. Our modeling approach allows for the direct comparison of humic substance binding constants and site densities to those previously published for proton and Cd binding onto natural consortia of bacteria. We then combine these constants into a unified model that accounts for the competition between bacterial surfaces and humic and fulvic acids in order to determine the relative importance of each component on the total Cd budget. The combined model is used to examine the relative contributions of bacteria and dissolved humic substances to Cd complexation in natural settings. Calculations are performed for three representative systems: (1) one with a maximum realistic concentration of bacteria and a minimum realistic concentration of humic substance, (2) one with a maximum realistic concentration of humic substance and a minimum concentration of bacteria, and (3) one with an intermediate concentration of both components. Our modeling results indicate that dissolved humic substances have 2 orders of magnitude more available binding sites than bacterial surfaces (per gram). Humic substances also have a greater affinity than bacterial surfaces for binding Cd over circumneutral pH ranges. The combined model results demonstrate that, depending upon their relative concentrations, both Cd-humic and Cd-bacteria complexes are capable of dominating Cd-speciation in specific natural environments. This modeling approach is useful in that it can easily be extended to include other metals and binding ligands; however, thermodynamic data must be gathered on additional components to facilitate the modeling of more realistic systems. Copyright © 2004 Elsevier Ltd
Recent Trends in Healthcare Utilization Among Children and Adolescents With Hypertension in the United States

The objective of this study was to evaluate the healthcare utilization of hospitalized children with hypertension. The Healthcare Cost and Utilization Project Kids' Inpatient Database, years 1997, 2000, 2003, and 2006, was used to identify hypertension hospitalizations. We examined the association of patient and hospital characteristics on hypertension charges. Data from each cohort year were used to analyze trends in charges. We found that 71282 pediatric hypertension hospitalizations generated $3.1 billion in total charges from 1997 to 2006. Approximately 68% were 10 to 18 years old, 55% were boys, and 47% were white. Six percent of claims with a diagnosis code for hypertension also had a diagnosis code for end-stage renal disease or renal transplant. The frequency of hypertension discharges increased over time (P=0.02 for each of age groups 2-9 years and 2-18 years; P=0.03 for age group 10-18 years), as well as the fraction of inpatient charges attributed to hypertension (P<0.0001). Length of stay and end-stage renal disease were associated with increases in hospitalization associated charges (P<0.0001 and P=0.03, respectively). During the 10-year study period, the frequency of hypertension-associated hospitalizations was increasing across all of the age groups, and the fraction of charges related to hypertension was also increasing. The coexisting condition of end-stage renal disease resulted in a significant increase in healthcare charges.
All-State Radiation Monitoring Network in the Czech Republic

Requirements of the All-State Radiation Monitoring Network in the Czech Republic have been establishedby Regulation No. 319/2002 Sb, and its function and organisation are described in Regulation No. 27/2006Sb. The All-State Radiation Monitoring Network in the Czech Republic consists of two components–permanentmonitoring and emergency monitoring. The activity of the whole network is provided by the State Office forNuclear Safety. The selected central authorities of the state administration participate in operation and providingparticular components. There are two different modes of the operation of these components–normal andemergency. The modes of operation are controlled by the State Office for Nuclear Safety. The activity of wholenetwork is focused on continuous monitoring of the radiation situation in the Czech Republic and on earlydetection of radiation accidents in and around the country as well as beyond it. The acquired data shall serveas a basis for adopting urgent and subsequent radiological protection provisions. Defence Science Journal, 2008, 58(6), pp.728 -733 , DOI:http://dx.doi.org/10.14429/dsj.58.1700
Team Projects And Peer Evaluations

The authors assign semester- or quarter-long team-based projects in several Computer Science and Finance courses. This paper reports on our experience in designing, managing, and evaluating such projects. In particular, we discuss the effects of team size and of various peer evaluation schemes on team performance and student learning. We report statistical measures of the students’ peer evaluations – do they always rate each other strongly or weakly? What are the means and ranges? More importantly, we discuss why we introduced these peer evaluations, and what effect they have had on student commitment and performance. We discuss a small number of cases where student participation was poor, and relate this to the peer evaluation process.
An introduction to the Synchronized Multimedia Integration Language

The Web, now a multimedia environment, can handle audio, images, text and video. However, creating TV-like multimedia presentations proves difficult. It either requires complex, timer-based programming in a scripting language (such as Javascript) or an authoring tool for multimedia presentations. To allow a broader audience to author multimedia presentations for the Web, the World Wide Web Consortium developed the Synchronized Multimedia Integration Language. SMIL, an easy-to-learn HTML-like language, allows the use of a text editor to write multimedia presentations. SMIL is a W3C recommendation, and several implementations are available. This article explains how to write a multimedia presentation in SMIL.
The Life History of the White-Pine Cone Beetle, Conophthorus coniperda

The life history of the white-pine cone beetle, Conophthorus coniperda (Schwarz), was studied in the vicinity of New Haven, Connecticut, in 1958-60. The various life stages and seasonal development are described. The adult female leaves its hibernation place in the litter in April, flies to a developing white-pine cone, and bores into the cone at its junction with the petiole and quickly kills it by girdling. A gallery is bored down the axis of the cone and eggs are deposited in niches along its length. There are 2 larval instars. New adults are present in July. Most adults stay within the infested cones, on the ground, until the following spring.
The effect of variable transport properties on mass transfer to a rotating disk

Abstract It is shown how one can calculate velocity and concentration profiles near a rotating disk taking into account variable transport properties, non-zero interfacial velocity, and finite Schmidt number. It is found that the surface is uniformly accessible for mass transfer and that the limiting current, in particular, and heat- and mass-transfer rates, in general, are proportional to the square root of the rotation speed, other conditions being the same. Specific results are given for deposition of copper from aqueous CuSO4 solutions, where it is found that the correction to Levich's classical equation due to variable properties is considerably greater than that due to either a non-zero interfacial velocity or a finite Schmidt number alone. Concentration overpotentials are defined and calculated for copper deposition.
Effect of rotary electric toothbrush versus manual toothbrush on periodontal status during orthodontic treatment

Adolescents with fixed orthodontic appliances frequently have increased levels of plaque accumulation and gingivitis. The purpose of this study was to determine whether a rotary electric toothbrush would be more effective than conventional toothbrushing in maintaining periodontal health in these patients. Forty adolescent patients were divided into equal groups matched for sex and age. Before and during placement of orthodontic appliances, one group was instructed in use of the rotary electric toothbrush and the other in the use of a conventional toothbrush; these instructions were reinforced at monthly visits thereafter. Baseline clinical assessments of Plaque Index, Gingival Index, and bleeding tendency were made on six standard teeth before appliances were placed. assessments were repeated at 1, 3, 6, 9, 12, and 18 months after appliances were placed. Intragroup and intergroup differences were tested by a two-way analysis of variance. At baseline there were no significant differences between the two groups for any study variable. During the 18-month study period, however, plaque accumulation and gingivitis increased significantly over baseline levels in the control group (p less than 0.01) but remained stable in the group using the rotary electric toothbrush. In addition, the control group showed significantly greater plaque (p less than 0.01), gingival inflammation (p less than 0.001), and gingival bleeding on probing (p less than 0.001) than did the treatment group from the 1- to 18-month examinations. These data suggest that the rotary electric toothbrush is more effective than conventional toothbrushes for removing plaque and controlling gingivitis in adolescents during orthodontic treatment with fixed appliances.
Folate Metabolism and the Risk of Down Syndrome.

Folate is an important vitamin that contributes to cell division and growth and is therefore of particular importance during infancy and pregnancy. Folate deficiency has been associated with slowed growth, anaemia, weight loss, digestive disorders and some behavioural issues. Adequate folate intake around the time of conception and early pregnancy can reduce the risk of certain problems including neural tube defects. It has been suggested that certain versions (polymorphisms) of some genes can increase the risk of conceiving a baby with Down syndrome. If this is the case, then people with Down syndrome may be more likely to carry these forms of these genes and to experience associated problems in folate metabolism. Studies to date have found conflicting results, suggesting that these gene variants may be part of a more complex picture. In this issue, a further study reports no association between the presence of a common polymorphism of one of these genes and the risk of having a child with Down syndrome among mothers of Northern Indian origin. This article reviews these challenging findings and looks at where investigations can now go to resolve these issues.
Isolated systolic hypertension in the elderly

SummaryIsolated systolic hypertension occurs principally in persons over 60 years of age, with its prevalence increasing from approximately 15% to twice that at age 75 years and over. The proportion of the U.S. population overage 60 years is also rising and is predicted to increase by nearly 40% by the end of the century. Excess cardiovascular risk, especially for stroke, is strongly associated with elevated systolic pressure. Isolated systolic hypertension is the most important unresolved issue in the management of high blood pressure. The importance of this issue is compounded by the fact that considerable uncertainty exists as to the risks and benefits of treatment. A pilot study to assess the feasibility of carrying out a full-scale trial of isolated systolic hypertension in the elderly is currently being undertaken. The selection and evaluation procedures to recruit at least 500 subjects and the randomized, double-blind stepped-care treatment programme to be followed in this long-term trial are descr...
Multiple prey traits, multiple predators: keys to understanding complex community dynamics

Natural communities can be complex. Such complexity makes it difficult to discern the mechanisms generating community structure. In this paper we review concepts and issues related to linking functional and community studies while also including greater complexity into the experimental realm. These principles are primarily illustrated with case studies involving predation ecology in a freshwater snail-fish-crayfish model system. The system illustrates how predator impacts on prey are mediated by multiple prey traits, correlations between traits, functional trade-offs in predator defence, interactions between predators, and interactions with other community members. We argue for a pluralistic approach to investigating mechanisms of community structure; that is, an approach that integrates many subdisciplines of ecology and evolution. We discuss four main areas that when used together yield important insights on community structure. First, selection gradient analyses formally link functional and community ecology. This formalisation is shown to help identify targets of selection, estimate environment-specific mortality rates, and identify agents of selection in complex communities. Second, we encourage increased focus on emergent community properties (results not predicted based on pairwise species interactions). Third, we emphasise that a community, rather than a web of species interactions, may more profitably be viewed as a network of trait interactions. This trait-centred view makes clear how indirect community effects arise between species that do not interact physically. This perspective also leads to our fourth topic, the integration of phenotypes. Just as populations evolve co-adapted suites of traits, so too should individuals embody integrated trait correlations, termed ‘trait integration’, rather than randomly assembled collections of phenotypes. All the perspectives mentioned above suggest that investigations should focus on multiple traits and multiple environments simultaneously, rather than singular, atomised components of complex systems. D 2002 Elsevier Science B.V. All rights reserved.
Site-specific high-resolution models of the monsoon for Africa and Asia

Abstract Using the macrophysical climate model of Bryson [Bryson, R.A., 1992. A macrophysical model of the Holocene intertropical convergence and jetstream positions and rainfall for the Saharan region. Meteorol. Atmos. Phys., 47, pp. 247–258], it is possible to calculate the monthly latitude of the jetstream and the latitude of the subtropical anticyclones. From these and modern climatic data, it is possible to model the two-century mean latitude of the intertropical convergence (ITC) month by month and estimate the monthly monsoon rainfall using the ITC–Rainfall model of Ilesanmi [Ilesanmi, O.O., 1971. An empirical formulation of an ITD rainfall model for the tropics — a case study of Nigeria. J. Appl. Meteorol., 10, pp. 882–891] and similar relationships. Input to this model is only calculated radiation and atmospheric optical depth estimated from a database of global volcanicity. Recent work has shown that it is possible to extend these estimates to both precipitation and temperature at specific sites, even in mountainous terrain. Testing of the model against archaeological records and climatic proxies is now underway, as well as refining the fundamental model. Preliminary indications are that the timing of fluctuations in the local climate is very well modeled. Especially well matched are the modeled Nile flood based on calculated rainfall on the Blue and White Nile watersheds and the level of Lake Moeris [Hassan, F., 1985. Holocene lakes and prehistoric settlements of the Western Faiyum, Egypt. J. Archaeol. Res., 13, pp. 483–501]. Modeled precipitation histories for specific sites in China, Thailand, the Arabian Peninsula, and North Africa will be presented and contrasted with the simulated rainfall history of Mesopotamia.
A Communitarian Note on Stakeholder Theory

Several powerful arguments have been advanced for a shift from a shareholder approach to a stakeholder approach towards corporate governance. These include the pioneering work by R. Edward Freeman,2 the important analysis based on contract theory by Thomas Donaldson and Thomas Dunfee,3 as well as Max Clarkson,4 the insights of Margaret Blair,5 and most recently an essay by Robert A. Phillips.6 Other fine writings include those by Steven Waliman and others in the Stetson Law Review.7 For an extensive review of the literature and numerous other references, see Donaldson and Preston.8 It should also be noted that Tony Blair stated his support for the stakeholder model.9 Reference here is limited to the literature that focuses on the nonnative issues raised by the stakeholder approach; there is a larger body of writing that deals with pragmatic merits and effects of taking into account the needs and values of various non-shareholder constituencies out of utilitarian consequentalist considerations. Nell Minow makes the distinction clear in legal terms when she points to the difference between allowing corporate executives to take into account the needs of constituents other than the shareholders (e.g. giving money to charity) and legally entitling groups other than the shareholders to have a voice in the management of the corporation.10 This pragmatic literature is not discussed here, as my interest is limited to adding a note to the existing literature that justifies the chartering of stakeholders.
Transcatheter arterial embolization in patients with kidney diseases: An overview of the technical aspects and clinical indications

Therapeutic embolization is defined as the voluntary occlusion of one or several vessels, and this is achieved by inserting material into the lumen to obtain transient or permanent thrombosis in the downstream vascular bed. There are a number of indications for this approach in urological practice, in particular for the patients with parenchymatous or vascular kidney disease. In this review, we present the different embolization techniques and the principally employed occluding agents, and then we present the principal clinical indications and we discuss other pathologies that may benefit from this non-invasive therapy. The complications, side effects and main precautions associated with this approach are also described.
De novo tumors after liver transplantation: A single‐institution experience

The aims of this analysis are to characterize the incidence and types of malignancies and tumor-specific mortality in our institution. Retransplantation, rejection episodes, and OKT3 use were evaluated. Our single-institution prospective database of 1,570 liver transplantations in 1,421 patients was analyzed. Data were statistically analyzed regarding sex, age at transplantation, time from transplantation to diagnosis of tumor, tumor type, and follow-up time. One hundred twenty-five patients (8.8%) developed de novo tumors; 69 patients were men, 56 patients were women. Seventeen patients received more than one allograft. De novo tumors were as follows: skin, 41; lymphomas, 35; lung, 11; colon, 6; anal, 2; rectal, 1; breast, 7; thyroid, 3; oropharyngeal squamous cell, 3; metastatic without primary tumor identified, 4; renal cell, 3; Kaposi's sarcoma, 1; angiosarcoma, 1; uterine, 1; ovarian, 1; pituitary, 1; pancreatic, 2; cholangiocarcinoma, 1; and esophageal, 1. These tumors developed in a statistically significant chronological sequence. Lung cancers and lymphomas showed shorter mean survival times, as well as greater mortality. OKT3 use and rejection did not show significance in tumor development. De novo tumors post-liver transplantation affected our population in a distribution similar to that of the general non-transplantation population. Intense short courses of immunosuppression for rejection were not as important as chronic immunosuppression in the development of tumors. The risk for development was not enough to preclude transplantation. We found that tumors developed in chronological fashion. Therefore, directed surveillance, patient education, and early detection may facilitate earlier treatment.
What's That Smell?

In philosophical discussions of the secondary qualities, color has taken center stage. Smells, tastes, sounds, and feels have been treated, by and large, as mere accessories to colors. We are, as it is said, visual creatures. This, at least, has been the working assumption in the philosophy of perception and in those metaphysical discussions about the nature of the secondary qualities. The result has been a scarcity of work on the "other" secondary qualities. In this paper, I take smells and place them front and center. I ask: What are smells? For many philosophers, the view that colors can be explained in purely physicalistic terms has seemed very appealing. In the case of smells, this kind of nonrelational view has seemed much less appealing. Philosophers have been drawn to versions of relationalism—the view that the nature of smells must be explained (at least in part) in terms of the effects they have on perceivers. In this paper, I consider a contemporary argument for this view. I argue that nonrelationalist views of smell have little to fear from this argument.
Hybrid optical processor for pattern recognition and classification using a generalized set of pattern functions.

A pattern recognition and classification system has been studied which computes the inner products of an input pattern with a generalized set of pattern functions. The system utilizes a filter whose impulse response consists of an amplitude superposition of a set of generalized pattern functions in phase-coded form and has a space–bandwidth product the same as that of a matched filter for one pattern function. Each pattern function in the general set may correspond to a different variation (e.g., scale or rotation) of the object to be detected. Because the amplitude superposition of the phase-coded pattern functions takes place in the digital computer, and the filter is created as a computer-generated hologram, the biasing problem of conventional, multiple exposure (intensity superposition) holograms is significantly reduced. This makes it possible to encode many more pattern functions than was previously possible using multiple exposure techniques. Furthermore, the use of computer-generated holograms eliminates the need to generate a transparency for each pattern function and complex phase code. To facilitate real-time operation a hybrid system was constructed consisting of a liquid crystal light valve for incoherent-to-coherent image conversion, a TV camera and image digitizer for image analysis, and a laser scanner to produce the computer-generated holograms. Both the TV camera/digitizer and the laser scanner systems were interfaced to a digital computer for automatic operation. Experimental results using the hybrid system are presented for pattern recognition of rotated and scaled objects and pattern classification. In the second half of the paper we provide an analysis on the SNR of the processor employing the coded-phase technique, on the diffraction efficiencies of computer-generated filters (amplitude superposition) vs conventional filters (intensity superposition), and on the number of pattern functions required for a certain recognition task.