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Showing papers by "State University of New York System published in 2002"


Journal ArticleDOI
TL;DR: With adequate recognition and effective engagement of all issues, BCI systems could eventually provide an important new communication and control option for those with motor disabilities and might also give those without disabilities a supplementary control channel or a control channel useful in special circumstances.

6,803 citations


Journal ArticleDOI
22 Nov 2002-Science
TL;DR: This work analyzed the flow of matter to extract pressures in excess of 1034 pascals, the highest recorded under laboratory-controlled conditions, and ruled out strongly repulsive nuclear equations of state from relativistic mean field theory and weakly repulsive equation of state with phase transitions at densities less than three times that of stable nuclei.
Abstract: Nuclear collisions can compress nuclear matter to densities achieved within neutron stars and within core-collapse supernovae. These dense states of matter exist momentarily before expanding. We analyzed the flow of matter to extract pressures in excess of 10 34 pascals, the highest recorded under laboratory-controlled conditions. Using these analyses, we rule out strongly repulsive nuclear equations of state from relativistic mean field theory and weakly repulsive equations of state with phase transitions at densities less than three times that of stable nuclei, but not equations of state softened at higher densities because of a transformation to quark matter.

1,119 citations


Journal ArticleDOI
TL;DR: Treatment with an insulin-sensitizing agent, such as metformin, in patients with type 2 diabetes mellitus may correct several of the primary pathophysiological abnormalities of the metabolic syndrome.
Abstract: Metformin is an insulin-sensitizing agent with potent antihyperglycemic properties. Its efficacy in reducing hyperglycemia in type 2 diabetes mellitus is similar to that of sulfonylureas, thiazolidinediones, and insulin. Metformin-based combination therapy is often superior to therapy with a single hypoglycemic agent. The antihyperglycemic properties of metformin are mainly attributed to suppressed hepatic glucose production, especially hepatic gluconeogenesis, and increased peripheral tissue insulin sensitivity. Although the precise mechanism of hypoglycemic action of metformin remains unclear, it probably interrupts mitochondrial oxidative processes in the liver and corrects abnormalities of intracellular calcium metabolism in insulin-sensitive tissues (liver, skeletal muscle, and adipocytes) and cardiovascular tissue.

1,086 citations


Journal ArticleDOI
TL;DR: The association between an exacerbation and the isolation of a new strain of a bacterial pathogen supports the causative role of bacteria in exacerbations of chronic obstructive pulmonary disease.
Abstract: Background The role of bacterial pathogens in acute exacerbations of chronic obstructive pulmonary disease is controversial. In older studies, the rates of isolation of bacterial pathogens from sputum were the same during acute exacerbations and during stable disease. However, these studies did not differentiate among strains within a bacterial species and therefore could not detect changes in strains over time. We hypothesized that the acquisition of a new strain of a pathogenic bacterial species is associated with exacerbation of chronic obstructive pulmonary disease. Methods We conducted a prospective study in which clinical information and sputum samples for culture were collected monthly and during exacerbations from 81 outpatients with chronic obstructive pulmonary disease. Molecular typing of sputum isolates of nonencapsulated Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, and Pseudomonas aeruginosa was performed. Results Over a period of 56 months, the 81 patients made a ...

1,009 citations


Journal ArticleDOI
05 Jul 2002-Science
TL;DR: This work subjected populations of an exploited fish to large, small, or random size-selective harvest of adults over four generations, finding that large-harvested populations initially produced the highest catch but quickly evolved a lower yield than controls.
Abstract: Fishery management plans ignore the potential for evolutionary change in harvestable biomass. We subjected populations of an exploited fish (Menidia menidia) to large, small, or random size-selective harvest of adults over four generations. Harvested biomass evolved rapidly in directions counter to the size-dependent force of fishing mortality. Large-harvested populations initially produced the highest catch but quickly evolved a lower yield than controls. Small-harvested populations did the reverse. These shifts were caused by selection of genotypes with slower or faster rates of growth. Management tools that preserve natural genetic variation are necessary for long-term sustainable yield.

927 citations


Journal ArticleDOI
TL;DR: The lateral geniculate nucleus is the best understood thalamic relay and serves as a model for all thAlamic relays, and may involve these corticothalamocortical 're-entry' routes to a far greater extent than previously appreciated.
Abstract: The lateral geniculate nucleus is the best understood thalamic relay and serves as a model for all thalamic relays. Only 5-10% of the input to geniculate relay cells derives from the retina, which is the driving input. The rest is modulatory and derives from local inhibitory inputs, descending inputs from layer 6 of the visual cortex, and ascending inputs from the brainstem. These modulatory inputs control many features of retinogeniculate transmission. One such feature is the response mode, burst or tonic, of relay cells, which relates to the attentional demands at the moment. This response mode depends on membrane potential, which is controlled effectively by the modulator inputs. The lateral geniculate nucleus is a first-order relay, because it relays subcortical (i.e. retinal) information to the cortex for the first time. By contrast, the other main thalamic relay of visual information, the pulvinar region, is largely a higher-order relay, since much of it relays information from layer 5 of one cortical area to another. All thalamic relays receive a layer-6 modulatory input from cortex, but higher-order relays in addition receive a layer-5 driver input. Corticocortical processing may involve these corticothalamocortical 're-entry' routes to a far greater extent than previously appreciated. If so, the thalamus sits at an indispensable position for the modulation of messages involved in corticocortical processing.

813 citations


Journal ArticleDOI
01 Dec 2002-Geology
TL;DR: In this paper, geochemical and isotopic data for Early Cretaceous Anjishan adakitic intrusive rocks that are in a continental setting unrelated to subduction were reported.
Abstract: To the best of our knowledge, modern adakites have not been documented in a nonarc environment. We report geochemical and isotopic data for Early Cretaceous Anjishan adakitic intrusive rocks that are in a continental setting unrelated to subduction. The Anjishan adakitic intrusive rocks, which are exposed in the Ningzhen area of east China, have high Sr/Y and La/Yb ratios coupled with low Yb and Y as well as relatively high MgO contents and Mg numbers (Mg#; 0.4-0.6), similar to products from slab melting. However, low ∈ N d ( t ) values (-6.8 to-9.7) and high ( 8 7 Sr/ 8 6 Sr) i (0.7053-0.7066) are inconsistent with an origin by slab melting. The tectonics and geochemistry lead us to conclude that adakitic magmas were most likely derived from partial melting of mafic material at the base of the continental crust. High Sr/Y and La/Yb ratios of the adakitic intrusive rocks suggest that garnet was stable as a residual phase during partial melting, implying that the crustal thickness exceeded 40 km in the Early Cretaceous. The present thickness of the crust in the Ningzhen area is only 30 km, and therefore the crust appears to have been thinned by at least ∼10 km since the Early Cretaceous. The relatively high MgO contents and Mg# of the Anjishan intrusive rocks suggest that adakitic magmas interacted with mantle rocks, possibly coinciding with lower-crustal delamination, which would also account for the observed thinning.

813 citations


Journal ArticleDOI
TL;DR: A major problem in leadership research and theory has been lack of agreement about which behavior categories are relevant and meaningful as discussed by the authors, and it is difficult to integrate findings from five decades of...
Abstract: A major problem in leadership research and theory has been lack of agreement about which behavior categories are relevant and meaningful. It is difficult to integrate findings from five decades of ...

790 citations


Journal ArticleDOI
S. Fukuda1, Y. Fukuda1, M. Ishitsuka1, Yoshitaka Itow1, Takaaki Kajita1, J. Kameda1, K. Kaneyuki1, K. Kobayashi1, Yusuke Koshio1, M. Miura1, S. Moriyama1, Masayuki Nakahata1, S. Nakayama1, Toshio Namba1, A. Okada1, N. Sakurai1, Masato Shiozawa1, Yoshihiro Suzuki1, H. Takeuchi1, Y. Takeuchi1, Y. Totsuka1, Shoichi Yamada1, Shantanu Desai2, M. Earl2, E. Kearns2, M. D. Messier2, J. L. Stone2, L. R. Sulak2, C. W. Walter2, M. Goldhaber3, T. Barszczak4, David William Casper4, W. Gajewski4, W. R. Kropp4, S. Mine4, D. W. Liu4, M. B. Smy4, Henry W. Sobel4, M. R. Vagins4, A. M. Gago5, K. S. Ganezer5, W. E. Keig5, R. W. Ellsworth6, S. Tasaka7, A. Kibayashi8, John G. Learned8, S. Matsuno8, D. Takemori8, Y. Hayato9, T. Ishii9, Takashi Kobayashi9, T. Maruyama9, Koji Nakamura9, Y. Obayashi1, Y. Obayashi9, Y. Oyama9, Makoto Sakuda9, Minoru Yoshida9, M. Kohama10, T. Iwashita10, Atsumu Suzuki10, A. K. Ichikawa9, A. K. Ichikawa11, T. Inagaki11, I. Kato11, Tsuyoshi Nakaya11, K. Nishikawa11, Todd Haines4, Todd Haines12, S. Dazeley13, S. Hatakeyama13, R. Svoboda13, E. Blaufuss14, M. L. Chen14, J. A. Goodman14, G. Guillian14, G. W. Sullivan14, D. Turč14, Kate Scholberg15, Alec Habig16, M. Ackermann17, J. Hill17, C. K. Jung17, Magdalena Malek17, K. Martens17, C. Mauger17, C. McGrew17, E. Sharkey17, B. Viren3, B. Viren17, C. Yanagisawa17, T. Toshito18, C. Mitsuda19, K. Miyano19, C. Saji19, T. Shibata19, Y. Kajiyama20, Y. Nagashima20, K. Nitta20, M. Takita20, Hyosun Kim21, S. B. Kim21, J. Yoo21, H. Okazawa, T. Ishizuka22, M. Etoh23, Y. Gando23, Takehisa Hasegawa23, Kunio Inoue23, K. Ishihara23, J. Shirai23, A. Suzuki23, Masatoshi Koshiba1, Y. Hatakeyama24, Y. Ichikawa24, M. Koike24, Kyoshi Nishijima24, Hirokazu Ishino25, Mikio Morii25, R. Nishimura25, Y. Watanabe25, D. Kielczewska4, D. Kielczewska26, H. G. Berns27, S. C. Boyd27, A. L. Stachyra27, R. J. Wilkes27 
TL;DR: In this paper, a number of different fits to solar neutrino mixing and mass square difference were performed using 1496 days of Super-Kamiokande-I's solar NE data.

680 citations


Book
23 Dec 2002
TL;DR: The authors used longitudinal data to examine the developmental consequences of gang membership, and its longer term influence on the life course, finding that multiple developmental deficits lead to gang membership and that membership leads to an increase in delinquency.
Abstract: Gang membership has long been understood to have a disruptive influence on adolescent development and to contribute disproportionately to the rate of delinquent crime. The nature of the impact, and the long-term effects on individuals, have not been well understood. This book uses longitudinal data to examine the developmental consequences of gang membership, and its longer term influence on the life course. This longitudinal approach is made possible by data from a study of antisocial behavior, The Rochester Youth Development Study, which followed one thousand adolescents through their early adult years. The subjects include delinquents who were gang members and others who were not, allowing the authors to compare motives, patterns of behavior, and recurring problems with caregivers and the law, education, peer relations, and career paths. The findings indicate that multiple developmental deficits lead to gang membership and that membership leads to an increase in delinquency.

652 citations


Journal ArticleDOI
TL;DR: In this paper, the authors explore the stages in the NSD process and explore how customer input may be obtained in the various stages of the development process, and how NSD managers obtained customer input in each stage.
Abstract: The purpose of this research is to answer the question: how can a new service development (NSD) program in the financial services industry be managed? More specifically, this research has two objectives: to explore the stages in the NSD process; and to explore how customer input may be obtained in the various stages of the development process. After a review of the new product development literature, the case study methodology involving in‐depth interviews with managers and their customers is described. Analysis of the data showed that there were ten stages in the NSD process, and whether those stages were managed linearly or sequentially was a function of the size of the firm. In addition, how NSD managers obtained customer input in each stage, was uncovered. Implications for NSD managers include which stages to concentrate on, and how to capture customer input.

Journal ArticleDOI
01 May 2002
TL;DR: An adaptive dynamic programming algorithm (ADPA) is described which fuses soft computing techniques to learn the optimal cost functional for a stabilizable nonlinear system with unknown dynamics and hard Computing techniques to verify the stability and convergence of the algorithm.
Abstract: Unlike the many soft computing applications where it suffices to achieve a "good approximation most of the time," a control system must be stable all of the time. As such, if one desires to learn a control law in real-time, a fusion of soft computing techniques to learn the appropriate control law with hard computing techniques to maintain the stability constraint and guarantee convergence is required. The objective of the paper is to describe an adaptive dynamic programming algorithm (ADPA) which fuses soft computing techniques to learn the optimal cost (or return) functional for a stabilizable nonlinear system with unknown dynamics and hard computing techniques to verify the stability and convergence of the algorithm. Specifically, the algorithm is initialized with a (stabilizing) cost functional and the system is run with the corresponding control law (defined by the Hamilton-Jacobi-Bellman equation), with the resultant state trajectories used to update the cost functional in a soft computing mode. Hard computing techniques are then used to show that this process is globally convergent with stepwise stability to the optimal cost functional/control law pair for an (unknown) input affine system with an input quadratic performance measure (modulo the appropriate technical conditions). Three specific implementations of the ADPA are developed for 1) the linear case, 2) for the nonlinear case using a locally quadratic approximation to the cost functional, and 3) the nonlinear case using a radial basis function approximation of the cost functional; illustrated by applications to flight control.

Journal ArticleDOI
17 Jan 2002-Neuron
TL;DR: All neocortical areas receive thalamic inputs, and most, possibly all, afferents reaching thalamus, ascending and cortical, are branches of axons that innervate lower (motor) centers, so that thalamocortical pathways can be viewed generally as monitors of ongoing motor instructions.

Journal ArticleDOI
TL;DR: This paper provides a summary of research on behavioral interventions for children with autism 8 years of age or younger published between 1996 and 2000 and offers recommendations for strengthening the existing research base and advancing behavioral technology to meet the needs of the defined target population.
Abstract: This paper provides a summary of research on behavioral interventions for children with autism 8 years of age or younger published between 1996 and 2000. The analysis is divided into four sections: (1) emerging themes in the technology of behavior support, (2) a review of existing research syntheses focusing on behavioral interventions, (3) a new literature review of current pertinent research, and (4) an evaluative discussion of the synthesis results and the field's future needs to develop effective behavioral interventions for young children with autism. The authors offer recommendations for strengthening the existing research base and advancing behavioral technology to meet the needs of the defined target population.

Journal ArticleDOI
TL;DR: Results are presented from all-atom, fully unrestrained ab initio folding simulations for a stable protein with nontrivial secondary structure elements and a hydrophobic core that is currently the smallest protein that displays two-state folding properties.
Abstract: We present results from all-atom, fully unrestrained ab initio folding simulations for a stable protein with nontrivial secondary structure elements and a hydrophobic core. The construct, “trpcage”, is a 20-residue sequence optimized by the Andersen group at University of Washington and is currently the smallest protein that displays two-state folding properties. Compared over the well-defined regions of the experimental structure, our prediction has a remarkably low 0.97 A Cα root-mean-square-deviation (rmsd) and 1.4 A for all heavy atoms. The simulated structure family displays additional features that are suggested by experimental data, yet are not evident in the family of NMR-derived structures.

Book ChapterDOI
TL;DR: In this article, the authors examined the relationship between anthropogenic nitrogen inputs and riverine nitrogen export and constructed budgets describing N inputs and losses for 16 catchments, which encompass a range of climatic variability and are major drainages to the coast of the North Atlantic Ocean along a latitudinal profile.
Abstract: Human activities have greatly altered the nitrogen (N) cycle, accelerating the rate of N fixation in landscapes and delivery of N to water bodies. To examine relationships between anthropogenic N inputs and riverine N export, we constructed budgets describing N inputs and losses for 16 catchments, which encompass a range of climatic variability and are major drainages to the coast of the North Atlantic Ocean along a latitudinal profile from Maine to Virginia. Using data from the early 1990’s, we quantified inputs of N to each catchment from atmospheric deposition, application of nitrogenous fertilizers, biological nitrogen fixation, and import of N in agricultural products (food and feed). We compared these inputs with N losses from the system in riverine export.

Journal ArticleDOI
TL;DR: It is suggested that risk and protective factors for adjustment across the first year of survivorship can be identified even prior to definitive surgery for breast cancer, particularly when both dispositional characteristics such as hope and situation‐specific coping strategies are considered.
Abstract: Given the marked individual variability in psychological adjustment in response to breast cancer, it is important to specify factors contributing to adaptive survivorship. This longitudinal study of 70 women with Stage I or II breast cancer tested the ability of situation-specific coping strategies and a more stable attribute, hope, to predict adjustment prospectively from the point shortly following diagnosis through the first year. Consonant with previous studies, coping through active acceptance at diagnosis predicted more positive adjustment across time, and avoidance-oriented coping predicted greater fear of cancer recurrence, over and above participant age and initial status on dependent variables. The hypothesis that coping through turning to religion would be more effective for less hopeful women was supported, and mixed support emerged for the hypothesis that approach-oriented coping strategies would yield greater adaptational benefits for women high in hope. Findings suggest that risk and protective factors for adjustment across the first year of survivorship can be identified even prior to definitive surgery for breast cancer, particularly when both dispositional characteristics such as hope and situation-specific coping strategies are considered.

Journal ArticleDOI
TL;DR: In this paper, a regression model (RivR-N) was developed that predicts the proportion of nitrogen removal from streams and reservoirs as an inverse function of the water displacement time of the body (ratio of water body depth to water time of travel).
Abstract: A regression model (RivR-N) was developed that predicts the proportion of N removed from streams and reservoirs as an inverse function of the water displacement time of the water body (ratio of water body depth to water time of travel). When applied to 16 drainage networks in the eastern U.S., the RivR-N model predicted that 37% to 76% of N input to these rivers is removed during transport through the river networks. Approximately half of that is removed in 1st through 4th order streams which account for 90% of the total stream length. The other half is removed in 5th order and higher rivers which account for only about 10% of the total stream length. Most N removed in these higher orders is predicted to originate from watershed loading to small and intermediate sized streams. The proportion of N removed from all streams in the watersheds (37-76%) is considerably higher than the proportion of N input to an individual reach that is removed in that reach (generally <20%) because of the cumulative effect of continued nitrogen removal along the entire flow path in downstream reaches. This generally has not been recognized in previous studies, but is critical to an evaluation of the total amount of N removed within a river network. At the river network scale, reservoirs were predicted to have a minimal effect on N removal. A fairly modest decrease (<10 percentage points) in the N removed at the river network scale was predicted when a third of the direct watershed loading was to the two highest orders compared to a uniform loading.

Journal ArticleDOI
TL;DR: In this article, the authors used computer algorithms for extracting features from scanned images of handwriting, e.g., line separation, slant, character shapes, etc., to quantitatively establish individuality by using machine learning approaches.
Abstract: Motivated by several rulings in United States courts concerning expert testimony in general, and handwriting testimony in particular, we undertook a study to objectively validate the hypothesis that handwriting is individual. Handwriting samples of 1500 individuals, representative of the U.S. population with respect to gender, age, ethnic groups, etc., were obtained. Analyzing differences in handwriting was done by using computer algorithms for extracting features from scanned images of handwriting. Attributes characteristic of the handwriting were obtained, e.g., line separation, slant, character shapes, etc. These attributes, which are a subset of attributes used by forensic document examiners (FDEs), were used to quantitatively establish individuality by using machine learning approaches. Using global attributes of handwriting and very few characters in the writing, the ability to determine the writer with a high degree of confidence was established. The work is a step towards providing scientific support for admitting handwriting evidence in court. The mathematical approach and the resulting software also have the promise of aiding the FDE.

Journal ArticleDOI
29 Nov 2002-Science
TL;DR: The zinc-finger gene-specific repressor element RE-1 silencing transcription factor/neuronal restricted silencing factor (REST/NRSF) can mediate extraneuronal restriction by imposing either active repression via histone deacetylase recruitment or long-term gene silencing using a distinct functional complex.
Abstract: The molecular mechanisms by which central nervous system–specific genes are expressed only in the nervous system and repressed in other tissues remain a central issue in developmental and regulatory biology. Here, we report that the zinc-finger gene-specific repressor element RE-1 silencing transcription factor/neuronal restricted silencing factor (REST/NRSF) can mediate extraneuronal restriction by imposing either active repression via histone deacetylase recruitment or long-term gene silencing using a distinct functional complex. Silencing of neuronal-specific genes requires the recruitment of an associated corepressor, CoREST, that serves as a functional molecular beacon for the recruitment of molecular machinery that imposes silencing across a chromosomal interval, including transcriptional units that do not themselves contain REST/NRSF response elements.

Journal ArticleDOI
TL;DR: It has now been confirmed that older subjects with increased arterial stiffness and elevated PP have higher cardiovascular morbidity and mortality.

Journal ArticleDOI
TL;DR: In this article, Li et al. examined several key mechanisms that can help increase customers' trust of e-commerce and decrease privacy concerns, including characteristic-based, transaction process-based and institution-based trust production.

Journal ArticleDOI
TL;DR: In this article, the overall performance of state-of-the-art atmospheric GCMs in simulating the climatological variations of summer monsoon rainfall over the Asian-western Pacific region and the systematic errors that are common to a group of GCMs were assessed.
Abstract: We assesses the overall performance of state-of-the-art atmospheric GCMs in simulating the climatological variations of summer monsoon rainfall over the Asian-Western Pacific region and the systematic errors that are common to a group of GCMs. The GCM data utilized are obtained from 10 GCM groups participated in the CLIVAR/Monsoon GCM Intercomparison Project. The model composite shows that the overall spatial pattern of summer monsoon rainfall is similar to the observed, although the western Pacific rainfall is relatively weak. For the simulated precipitation over the western Pacific, the models can be classified into two categories. The first category of models simulates the precipitation more confined to the equatorial region and weaker precipitation in the subtropical western Pacific compared to the observed. The second category of models simulates large precipitation in the subtropical western Pacific but the region is shifted to the north by 5–10°. None of the models realistically reproduce the observed Mei-yu rain band in the region from the East China Sea to the mid Pacific. Most of the models produce a rain band along the continental side of East Asia. The climatological variations of simulated summer rainfall are examined in terms of their amplitude and their principal EOF modes. All models simulate larger amplitudes of the climatological seasonal variation of Indian summer monsoon than the observed, though most models simulate smaller amplitudes in the western Pacific. The ten model composite produces four leading EOF modes over the Asian-western Pacific region, which are remarkably similar to the observed counterparts. The first and second eigenmodes, respectively, represent the smoothed seasonal march of broad-scale monsoon and the onsets of the Indian and East Asian summer monsoon. The third and fourth modes relate to the climatological intraseasonal oscillation (CISO). In contrast to the model composite, several models fail to reproduce the first principal mode, and most models do not reproduce the observed modes higher than the second. The CISO of precipitation is also examined over the Indian monsoon and the East Asia-western Pacific monsoon regions separately.

Journal ArticleDOI
TL;DR: The authors analyzes the distinctive forms that collective memories take in the age of globalization, and studies the transition from national to cosmopolitan memory cultures in the cross-culture memory transfer process.
Abstract: This article analyzes the distinctive forms that collective memories take in the age of globalization. It studies the transition from national to cosmopolitan memory cultures. Cosmopolitanism refer...

Journal ArticleDOI
TL;DR: The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO 3 − ) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A.
Abstract: The feasibility of using nitrogen and oxygen isotope ratios of nitrate (NO 3 − ) for elucidating sources and transformations of riverine nitrate was evaluated in a comparative study of 16 watersheds in the northeastern U.S.A. Stream water was sampled repeatedly at the outlets of the watersheds between January and December 1999 for determining concentrations, δ 15N values, and δ 180 values of riverine nitrate.

Journal ArticleDOI
07 Jun 2002-Science
TL;DR: KNOTTEDI-like homeobox (KNOXI) genes regulate development of the leaf from the shoot apical meristem (SAM) and may regulate leaf form, but not all simple leaves develop similarly, and final leaf morphology may not be an adequate predictor of homology.
Abstract: KNOTTEDI-like homeobox (KNOXI) genes regulate development of the leaf from the shoot apical meristem (SAM) and may regulate leaf form. We examined KNOXI expression in SAMs of various vascular plants and found that KNOXI expression correlated with complex leaf primordia. However, complex primordia may mature into simple leaves. Therefore, not all simple leaves develop similarly, and final leaf morphology may not be an adequate predictor of homology.

Journal ArticleDOI
TL;DR: In this article, the authors examined the issue through a modeling study that integrated road maps and traffic-volume data with simulated movements of (1) small-bodied pond turtles, (2) large-bodied Pond turtles, and (3) terrestrial and semiterrestrial ("land") turtles.
Abstract: Road mortality is suspected to have contributed to widespread population declines in turtles in the United States, a country with exceptionally high turtle diversity. We examined the issue through a modeling study that integrated road maps and traffic-volume data with simulated movements of (1) small-bodied pond turtles, (2) large-bodied pond turtles, and (3) terrestrial and semiterrestrial ("land") turtles. Our model predicted that road networks typical of the northeastern, southeastern, and central regions have the potential to limit land-turtle populations and, to a lesser extent, populations of large-bodied pond turtles. Nowhere are populations of small-bodied pond turtles likely threatened regionally by road mortality. We conclude that the demographic traits of some turtles, in combination with their mobility, may jeopardize population persistence within road networks typical of the eastern and central United States.

Journal ArticleDOI
TL;DR: In this article, the authors argue that as the force of humanity increases on the planet, ecosystem service valuation will need to switch from choosing among resources to valuing the avoidance of catastrophic ecosystem change.

Journal ArticleDOI
TL;DR: An understanding of mixed-bacterial metabolism, knowledge of how to manipulate and work with mixed bacteria, and the use of a bacterial metabolic vector approach have led to a more ecological focus for dealing with dental caries, and new means of developing and evaluating anti-caries agents directed toward microbial mixtures that counter excess acid accumulation and tooth demineralization.
Abstract: For more than 100 years, investigators have tried to identify the bacteria responsible for dental caries formation and to determine whether their role is one of specificity. Frequent association of Lactobacillus acidophilus and Streptococcus mutans with caries activity gave credence to their being specific cariogens. However, dental caries occurrence in their absence, and the presence of other bacteria able to produce substantial amounts of acid from fermentable carbohydrate, provided arguments for non-specificity. In the 1940s, Stephan found that the mixed bacteria in dental plaque produced a rapid drop in pH following a sugar rinse and a slow pH return toward baseline. This response became a cornerstone of plaque and mixed-bacterial involvement in dental caries causation when Stephan showed that the pH decrease was inversely and clearly related to caries activity. Detailed examination of the pH (acid-base) metabolisms of oral pure cultures, dental plaque, and salivary sediment identified the main bacteria and metabolic processes responsible for the pH metabolism of dental plaque. It was discovered that this metabolism in different individuals, in plaque in different dentition locations within individuals, and in individuals of different levels of caries activity could be described in terms of a relatively small number of acid-base metabolic processes. This led to an overall bacterial metabolic vector concept for dental plaque, and helped unravel the bacterial involvement in the degradation of the carbohydrate and nitrogenous substrates that produce the acids and alkali that affect the pH and favor and inhibit dental caries production, respectively. A central role of oral arginolytic and non-arginolytic acidogens in the production of the Stephan pH curve was discovered. The non-arginolytics could produce only the pH fall part of this curve, whereas the arginolytics could produce both the fall and the rise. The net result of the latter was a less acidic Stephan pH curve. Both kinds of bacteria are numerous in dental plaque. By varying their ratios, we were easily able to produce Stephan pH curves indicative of different levels of caries activity. This and substantial related metabolic and microbial data indicated that it is the proportions and numbers of acid-base-producing bacteria that are at the core of dental caries activity. The elimination of S. mutans, as with a vaccine, was considered to have little chance of success in preventing dental caries in humans, since, in most cases, this would simply make more room for one or more of the many acidogens remaining. An understanding of mixed-bacterial metabolism, knowledge of how to manipulate and work with mixed bacteria, and the use of a bacterial metabolic vector approach as described in this article have led to (1) a more ecological focus for dealing with dental caries, and (2) new means of developing and evaluating anti-caries agents directed toward microbial mixtures that counter excess acid accumulation and tooth demineralization.

Journal ArticleDOI
TL;DR: The influence of vertical wind shear on the azimuthal distribution of cloud-to-ground lightning in tropical cyclones was examined using flash locations from the National Lightning Detection Network as discussed by the authors.
Abstract: The influence of vertical wind shear on the azimuthal distribution of cloud-to-ground lightning in tropical cyclones was examined using flash locations from the National Lightning Detection Network. The study covers 35 Atlantic basin tropical cyclones from 1985–99 while they were over land and within 400 km of the coast over water. A strong correlation was found between the azimuthal distribution of flashes and the direction of the vertical wind shear in the environment. When the magnitude of the vertical shear exceeded 5 m s−1, more than 90% of flashes occurred downshear in both the storm core (defined as the inner 100 km) and the outer band region (r = 100–300 km). A slight preference for downshear left occurred in the storm core, and a strong preference for downshear right in the outer rainbands. The results were valid both over land and water, and for depression, storm, and hurricane stages. It is argued that in convectively active tropical cyclones, deep divergent circulations oppose the ver...