bluuebunny/crossref_metadata_2025 huggingface dataset:
Loss of sensory input increases the intrinsic excitability of layer 5 pyramidal neurons in rat barrel cortex
Authors: Breton Jean‐Didier , Stuart Greg J.
Published: September 2009

Development of the cortical map is experience dependent, with different critical periods in different cortical layers. Previous work in rodent barrel cortex indicates that sensory deprivation leads to changes in synaptic transmission and plasticity in layer 2/3 and 4. Here, we studied the impact of sensory deprivation on the intrinsic properties of layer 5 pyramidal neurons located in rat barrel cortex using simultaneous somatic and dendritic recording. Sensory deprivation was achieved by clipping all the whiskers on one side of the snout. Loss of sensory input did not change somatic active and resting membrane properties, and did not influence dendritic action potential (AP) backpropagation. In contrast, sensory deprivation led to an increase in the percentage of layer 5 pyramidal neurons showing burst firing. This was associated with a reduction in the threshold for generation of dendritic calcium spikes during high‐frequency AP trains. Cell‐attached recordings were used to assess changes in the properties and expression of dendritic HCN channels. These experiments indicated that sensory deprivation caused a decrease in HCN channel density in distal regions of the apical dendrite. To assess the contribution of HCN down‐regulation on the observed increase in dendritic excitability following sensory deprivation, we investigated the impact of blocking HCN channels. Block of HCN channels removed differences in dendritic calcium electrogenesis between control and deprived neurons. In conclusion, these observations indicate that sensory loss leads to increased dendritic excitability of cortical layer 5 pyramidal neurons. Furthermore, they suggest that increased dendritic calcium electrogenesis following sensory deprivation is mediated in part via down‐regulation of dendritic HCN channels.
Organopalladium catalyst on S-terminated GaAs(001)-(2×6) surface
Authors: Konishi Tomoya , Toujyou Takashi , Ishikawa Takuma , Bell Gavin R. , Tsukamoto Shiro
Published: September 2009

Organopalladium molecules, such as Pd(CH3COO)2 ({Pd}), immobilized on the S-terminated GaAs(001), termed GaAs–S–{Pd} have high catalytic activity and cycle durability in the Mizoroki–Heck reaction. It is thought that the presence of Ga–S bonds in the single atomic layer S-termination is essential for these catalytic properties despite the much higher thickness (∼100nm) of the {Pd} films. In this study, the authors demonstrate the retention of Ga–S bonds in ultrathin GaAs–S–{Pd} by using reflection high-energy electron diffraction and scanning tunneling microscopy (STM). The ultrathin GaAs–S–{Pd} was prepared by using a vapor-deposition technique. Deposited {Pd} was observed as ∼1nm dotlike structures with STM. The adsorption rate of {Pd} was also investigated.
Evaluation of the MyWellness Key accelerometer
Authors: Herrmann S D , Hart T L , Lee C D , Ainsworth B E
Published: September 2009

Objective

To examine the concurrent validity of the Technogym MyWellness Key accelerometer against objective and subjective physical activity (PA) measures.

Design

Randomised, cross-sectional design with two phases. The laboratory phase compared the MyWellness Key with the ActiGraph GT1M and the Yamax SW200 Digiwalker pedometer during graded treadmill walking, increasing speed each minute. The free-living phase compared the MyWellness Key with the ActiGraph, Digiwalker, Bouchard Activity cord (BAR) and Global Physical Activity Questionnaire (GPAQ) for seven continuous days. Data were analysed using Spearman rank-order correlation coefficients for all comparisons.

Setting

Laboratory and free-living phases.

Participants

Sixteen participants randomly stratified from 41 eligible respondents by sex (n=8 men; n=8 women) and PA levels (n=4 low, n=8 middle and n=4 high active).

Results

There was a strong association between the MyWellness Key and the ActiGraph accelerometer during controlled graded treadmill walking (r=0.91, p<0.01) and in free-living settings (r=0.73–0.76 for light to vigorous PA, respectively, p<0.01). No associations were observed between the MyWellness Key and the BAR and GPAQ (p>0.05).

Conclusions

The MyWellness Key has a high concurrent validity with the ActiGraph accelerometer to detect PA in both controlled laboratory and free-living settings.
Lung function and indicators of exposure to indoor and outdoor particulate matter among asthma and COPD patients
Authors: de Hartog J J , Ayres J G , Karakatsani A , Analitis A , Brink H ten , Hameri K , Harrison R , Katsouyanni K , Kotronarou A , Kavouras I , Meddings C , Pekkanen J , Hoek G
Published: September 2009

Objectives:

Misclassification of exposure related to the use of central sites may be larger for ultrafine particles than for particulate matter ⩽2.5 μm and ⩽10 μm (PM2.5and PM10) and may result in underestimation of health effects. This paper describes the relative strength of the association between outdoor and indoor exposure to ultrafine particles, PM2.5and PM10and lung function.

Methods:

In four European cities (Helsinki, Athens, Amsterdam and Birmingham), lung function (forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1) and peak expiratory flow (PEF)) was measured three times a day for 1 week in 135 patients with asthma or chronic obstructive pulmonary disease (COPD), covering study periods of >1 year. Daily concentrations of particle number, PM2.5and PM10were measured at a central site in each city and both inside and outside the subjects’ homes.

Results:

Daily average particle number concentrations ranged between 2100 and 66 100 particles/cm3. We found no association between 24 h average particle number or particle mass concentrations and FVC, FEV1and PEF. Substituting home outdoor or home indoor concentrations of particulate air pollution instead of the central site measurements did not change the observed associations. Analyses restricted to asthmatics also showed no associations.

Conclusions:

No consistent associations between lung function and 24 h average particle number or particle mass concentrations were found in panels of patients with mild to moderate COPD or asthma. More detailed exposure assessment did not change the observed associations. The lack of association could be due to the high prevalence of medication use, limited ability to assess lagged effects over several days or absence of an effect.
Circulating adhesion molecules after short-term exposure to particulate matter among welders
Authors: Fang S C , Eisen E A , Cavallari J M , Mittleman M A , Christiani D C
Published: September 2009

Background:

Studies from several countries indicate that welders experience increased risk of mortality and morbidity from ischaemic heart disease. Although the underlying mechanisms are unclear, vascular responses to particulate matter contained in welding fumes may play a role. To investigate this, we studied the acute effects of welding fume exposure on the endothelial component of vascular function, as measured by circulating adhesion molecules involved in leukocyte adhesion (sICAM-1 and sVCAM-1) and coagulation (vWF).

Methods:

A panel of 26 male welders was studied repeatedly across a 6 h work-shift on a high exposure welding day and/or a low exposure non-welding day. Personal PM2.5exposure was measured throughout the work-shift. Blood samples were collected in the morning (baseline) prior to the exposure period, immediately after the exposure period, and the following morning. To account for the repeated measurements, we used linear mixed models to evaluate the effects of welding (binary) and PM2.5(continuous) exposure on each blood marker, adjusting for baseline blood marker concentration, smoking, age and time of day.

Results:

Welding and PM2.5exposure were significantly associated with a decrease in sVCAM-1 in the afternoon and the following morning and an increase in vWF in the afternoon.

Conclusions:

The data suggest that welding and short-term occupational exposure to PM2.5may acutely affect the endothelial component of vascular function.
The Salmon Terminal Fishery: a Practical, Comprehensive Timing Model
Authors: Schnute Jon , Sibert John
Published: September 2009

This paper presents a comprehensive model for analysis of data from a salmon terminal fishery. The model includes a new description of salmon run curves, tailored form earlier models of biological growth. It also includes a new equation to describe the process of fishing from a pool of fish that belong to various stages of the salmon run. It allows for variable run timing between fishery and hatchery, and it incorporates test fishery data in a systematic way. A likelihood function is derived that gives an objective criterion for estimating parameters associated with run timing, the fishery, and the test fishery. The model is applied to 4 yr of historical data on the chinook (Oncorhynchus tshawytscha) fishery in Barkley Sound and Alberni Inlet, British Columbia, Canada. Run timing proves to be remarkably consistent from year to year. Time spent by the fish in the fishery is ill-determined from the data, but most other important parameters are relatively insensitive to this uncertainty.
Biochemical Evidence that Winter Flounder (Pseudopleuronectes americanus) have Induced Hepatic Cytochrome P-450-Dependent Monooxygenase Activities
Authors: Foureman Gary L. , White Jr. Nathaniel B. , Bend John R.
Published: September 2009

Livers from winter flounder (Pseudopleuronectes americanus) captured near Mount Desert Island, Maine, showed marked variation in hepatic benzo[a]pyrene hydroxylase (AHH; from 0.04 to 8.8 FU∙min−1∙mg protein−1) and 7-ethoxyresorufin deethylase activities (7-ERD; from < 2 to 1165 pmol∙min−1∙mg protein−1), and a dichotomy in the effect of 7,8-benzoflavone (ANF) added in vitro on AHH activity. Based on this ANF effect, the flounder could be divided into two groups. One group had high 7-ERD activity and high AHH activity which was inhibited by ANF; the other group had low 7-ERD activity and low AHH activity which was enhanced by ANF. Sex, weight, length, liver weight, gonad weight/body weight ratio, and liver/body weight ratio explained only a small part of the variability in hepatic AHH activities. Electrophoretograms of hepatic microsomes from flounder treated with 1,2,3,4-dibenzanthracene (DBA) or 5,6-benzoflavone (βNF) showed a novel or enriched polypeptide species present near 57 000 daltons, in the molecular weight (MW) range of known cytochrome P-450 isozymes. A polypeptide of similar MW was only faintly discernable in liver microsomes from untreated flounder whose hepatic AHH activity was much lower than that of the treated flounder, whereas a band of this MW was prominent in hepatic microsomes from untreated flounder with high hepatic AHH activity. These results suggest that many of the winter flounder captured near Mount Desert Island, Maine have induced hepatic monooxygenase activity due to exposure to PAH or PAH-like inducers present in their natural habitat.
Tidal Mixing and Summer Plankton Distributions in Hecate Strait, British Columbia
Authors: Perry R. Ian , Dilke Bruce R. , Parsons Timothy R.
Published: September 2009

Summer plankton distributions in Hecate Strait, northern British Columbia, were examined during 1979 and 1980 and compared with tidal mixing characteristics. Calculations of the Simpson–Hunter tidal stratification parameter (h∙U−3) indicate that most of Hecate Strait is potentially stratified in summer (in the absence of excessive storms), with a well-mixed region over the shallow shelf adjacent to the Queen Charlotte Islands. Vertical temperature profiles collected from a coastal oil tanker ship of opportunity confirmed the presence of mixed and stratified water masses as predicted. Near-surface concentrations of chlorophyll a, nutrients, diatoms, and copepods were lower in the mixed region (< 1 μg Chl. a∙L−1) than the statified region, but highest (5 μg Chl. a∙L−1) at the front between these mixing regimes. We believe that low phytoplankton biomass in western mixed waters is due to nutrient rather than light limitation, whereas possible advection of nutrients along the edge of the western shelf may support the higher biomass of the frontal region. Such a frontal zone is likely important to groundfish production in this region.
Nocturnal Inshore Movement of the Mimic Shiner (Notropis volucellus): a Possible Predator Avoidance Behavior
Authors: Hanych David A. , Ross Michael R. , Magnien Robert E. , Suggars Amy L.
Published: September 2009

Diel seining documented a significant summer nocturnal inshore movement of the mimic shiner (Notropis volucellus) in Lake Itasca, Minnesota. This species initiated inshore movement at sunset, occupied the nearshore area throughout the night, and moved offshore by sunrise. Mimic shiners were collected in less than 1 m of water throughout inshore areas with sparsely developed macroscopic vegetation. Greatest relative abundance was observed at sites possessing the greatest expanse of sparsely or nonvegetated substrate. Relative abundance at inshore sites may be related to habitat characteristics of the sites or to the proximity of feeding habitat. These diel movements differed markedly from those exhibited by the mimic shiner in other lakes. The inshore movement in Lake Itasca may function to reduce crepuscular and nocturnal predation pressure. Our data support the hypothesis that freshwater fishes may possess behavioral plasticity sufficient to alter movement and distribution patterns according to prevailing conditions and that predation pressure may be important in altering prey behavioral patterns.
Variation in Zinc Adsorption and Transport During Growth of Chlamydomonas variabilis (Chlorophyceae) in Batch Culture with Daily Addition of Zinc
Authors: Bates Stephen S. , Létourneau Martin , Tessier André , Campbell Peter G. C.
Published: September 2009

Chlamydomonas variabilis Dangeard was grown in batch culture under constant irradiance in the absence (A) or presence (B) of added zinc. Growth parameters were followed for 6 d and aliquots were removed daily from both cultures A and B for the measurement of adsorption and transport of zinc in short-term (10-min) incubations with 65Zn. The concentration of EDTA-extractable zinc ([Zn]a) and the flux (F) of zinc across the cell membrane both decreased with increasing culture age. Values of [Zn]a and F varied depending on when the measurements were made during the growth cycle and on the history of the inoculum. In culture B, previous growth in the presence of 7.0 μmol Zn2+∙L−1 resulted in larger values of [Zn]a but smaller fluxes than did growth in the absence of added zinc. Regardless of culture age, the dependence of [Zn]a on the concentration of Zn2+ in solution ([Zn2+]b) could be described by Langmuir adsorption isotherms. Conditional adsorption equilibrium constants, Kθ, were greater for cells previously grown in the presence of added zinc but showed no clear trend with culture age. Rate constants for zinc transport were smaller for cells grown with added zinc and decreased slightly with increasing culture age. The number of binding sites per unit cell surface, Q, decreased markedly with culture age, as did values obtained for [Zn]a. The variation in metal adsorption and transport as a function of the physiological state of the cells should be considered when trace metal uptake is modeled and when phytoplankton are used to assess metal toxicity.
Migrations saisonnières du homard (Homarus americanus) entre la côte et les lagunes des Îles-de-la-Madeleine
Authors: Munro Jean , Therriault Jean-Claude
Published: September 2009

During the summers of 1978 and 1979, the lobster population of the lagoons of the Magdalen Islands was investigated using tag/recapture techniques and direct observations by divers. The results show an active migration pattern of lobsters into (from mid-May to the end of June) and out of (from the beginning to the end of October) the lagoons, linked to seasonal water temperature variations. Following migration out of the lagoons the lobster stay mainly close to the entrance of the lagoons; this principally explains the high percentage of returns to the lagoon the following spring. To explain the much higher percentage of males in the lagoons than in the coastal area, we suggest the existence of a positive selection for mobility of the males during the spring migration. However, the differences in size structure distribution between the coast and the lagoons are mostly due to variations in commercial fishing pressure.
Modification of Swimming Mode and Stamina in Two Stocks of Coho Salmon (Oncorhynchus kisutch) by Differing Levels of Long-Term Continuous Exercise
Authors: Besner M. , Smith L. S.
Published: September 2009

Coho salmon (Oncorhynchus kisutch) smolts from two different stocks were exercised continuously for 40 d at water velocities of 0.2 (control), 1.0, 1.5, and 2.0 body fork lengths per second. Their critical velocities and swimming characteristics were determined using a Blazka-type respirometer–stamina swimming chamber immediately after training and after 2 mo of rest. Endurance increased in exercised fish compared with control groups and the improvement was maintained after the period of rest. Swimming modes in freshwater differed between the two stocks, and it is suggested that these were adaptations resulting from differing genetical backgrounds. Continuous moderate exercise modified swimming modes in seawater. Long-term low water velocity regimes before release in the ocean might be a profitable rearing strategy for the survival of coho salmon because it allows an economy of energy during their oceanic migrations and improves their homeodynamic capacity.
Photoperiodic and Ecdysial Control of Vitellogenesis in Lobsters (Homarus) (Decapoda, Nephropidae)
Authors: Nelson Keith , Hedgecock Dennis , Borgeson Will
Published: September 2009

The timing of molts and of subsequent egg extrusion by female American lobsters (Homarus americanus) in the laboratory under near-ambient conditions at Bodega Bay suggested that final vitellogenesis was initiated only during the months between the vernal and autumnal equinoxes. In an experiment, the change from short-day (LD 8:16) to long-day (LD 16:8) photoperiod (long-day onset, LDO) began a 120-d period during which vitellogenesis could be initiated. Molting within this 120-d period was associated with a delay of as much as 80 d in the time of subsequent extrusion.
Growth Rate and Survival in Pure Population Matings and Crosses of the Oyster Crassostrea virginica
Authors: Mallet Andre L. , Haley L. E.
Published: September 2009

Phenotypic differences were observed among pure population matings and crosses grown in two natural environments for the following characters: larval shell length, juvenile and adult shell length, weight, and survival at different times. For growth characters, the phenotypic variability between locations was greater than the variability among genetic groups within locations; however, the magnitude of the differences depended on the locality. The crosses exhibited higher survival than pure population matings, and locality had no effect on survival. In growth and survival, some crosses deviated positively from the mean of the parental populations. This may be a manifestation of heterosis. The genetic enhancement of commercially important characters in shellfish will eventually require the formation of a closed breeding unit with a broad genetic base for domestication and selection. It is recommended that an evaluation of natural populations as outlined in this study is a necessary prerequisite to achieve this objective.
Cichlid Stocking and the Decline of the Galilee Saint Peter's Fish (Sarotherodon galilaeus) in Lake Kinneret, Israel
Authors: Gophen Moshe , Drenner Ray W. , Vinyard Gary L.
Published: September 2009

The catch of the Galilee Saint Peter's fish (Sarotherodon galilaeus), relative to the catch of nonstocked fish of Lake Kinneret, has declined since 1958 despite the intensive stocking of S. galilaeus fingerlings. The reduced relative S. galilaeus catch coincides with stocking of the Jordan Saint Peter's fish, S. aureus. Laboratory analyses of S. galilaeus and S. aureus feeding behavior and selectivities suggest that they may compete for zooplankton, a major food resource for both species. The decline of S. galilaeus means not only a relative reduction of the most valuable commercial species but also a disruption of the trophic dynamics of the lake. Sarotherodon galilaeus is the primary consumer of the dominant alga in the lake, the bloom-forming dinoflagellate, Peridinium, and thus is important in maintaining water quality. The impact of stocking practices on S. galilaeus suggests that fisheries policies must be integrated into the overall program of water quality management for Lake Kinneret and lakes in general.
Homeostatic Characteristics of Single Species Fish Stocks in Arctic Lakes
Authors: Johnson Lionel
Published: September 2009

The results of investigations on the fish stocks of seven Arctic lakes covering a period of 23 yr are described. These lakes have remained largely undisturbed since their formation in late glacial times; all but one are completely autonomous and of comparatively small size. Such lakes provide a unique opportunity for the development and testing of conceptual models. In all cases the only fish species present is Arctic charr, Salvelinus alpinus. Length frequency distributions derived from gillnet catch curves are shown to be, within reasonable limits, representative of the actual populations in the lake, and not artifacts of the sampling procedure. Length frequency curves show a unimodal or bimodal distribution and this structure, in the absence of perturbation, appears to remain constant indefinitely. Individuals are of great age but age-at-length is highly variable. Age and size structure are shown to be comparable with the age and size structure of the dominant tree species in a climax forest; it is concluded that forces of great generality fashion these configurations. It is hypothesized that all species tend to move towards a state of least energy dissipation; this can be most readily seen in the dominant species at the climax in an autonomous system. The dominant species is characterized by large individual size, a high degree of uniformity, high total biomass, great mean age, indeterminate age-at-death, and a low incidence of replacement stock. After severe perturbation it is shown that the charr stock returns to a state of least dissipation without oscillation. Absence of oscillation during the return to the initial state, combined with the long-term stability shown in control lakes, indicates the presence of an effective damping mechanism; this in turn indicates the existence of organization within the stock as a whole. Organization develops through an interactive mechanism described under the doctrine of homeokinesis, which is responsible for energy equipartitioning and the maintenance of uniformity. These concepts help to explain phenomena observed in more complex systems and help our understanding of ecosystem functioning.
The Strait of Georgia: functional anatomy of a coastal sea
Authors: LeBlond Paul H.
Published: September 2009

The physical oceanography of the Strait of Georgia, a large estuary on the coast of British Columbia, is reviewed in the light of recent observations and theoretical developments. The review focusses on a discussion of physical mechanisms rather than on a description of properties. The responses of the Strait to the dominant forcing processes, the tides, freshwater runoff, and atmospheric inputs, are described first. Interactions between these responses are then shown to give rise (or at least to influence) other phenomena such as fronts, deepwater renewal, and oceanic exchange processes. Recent observations of deep residual flows as well as theoretical efforts to explain their nature are also discussed. The present state of the understanding of dynamics is assessed against the requirements of predictive modeling; whereas high-frequency phenomena such as tides and upper layer dynamics are approaching an engineering level of predictability, low-frequency processes (water renewal, oceanic exchange, deep residual flows) remain inadequately documented, poorly understood, and unpredictable. Some suggestions are presented for future observational and theoretical research.
Review of the Biological Oceanography of the Strait of Georgia: Pelagic Environment
Authors: Harrison P. J. , Fulton J. D. , Taylor F. J. R. , Parsons T. R.
Published: September 2009

Different components of the food web in the Strait of Georgia are reviewed. The phytoplankton are dominated by diatoms; however, flagellates may dominate in the winter. Chlorophyll a concentrations may range from < 1 mg∙m−3 in the winter to > 15 mg∙m−3 during blooms. The average annual primary productivity is about 280 g C∙m−2 for the strait, but it is higher in frontal areas at the north and south ends of the strait and near the Fraser River plume. Light limits primary productivity during the winter months, while nutrients (nitrogen) and grazing are the limiting factors during the late spring and summer. Turbidity and salinity effects occur near the Fraser River plume. The surface macrozooplankton community is composed chiefly of copepods. Mid- and deep-water communities consist of euphausiids, chaetognaths, and some deep-living copepods, which overwinter at depth. The standing stock of macrozooplankton (> 350 μm) to 400 m, ranges from 0.1 to 2.0 g wet wt∙m−3. Few estimates of secondary production and standing stock estimates of microzooplankton have been made. Horizontal patches of zooplankton have been encountered and may be important feeding sites for some fish. Standing stock associations of the dominant species in the food web of the strait are reasonably well known, but assessment of food web dynamics from these limited standing stock measurements is often inaccurate. There is a noticeable absence of data on how rate processes affect standing stocks, and it is particularly an understanding of these interrelationships that is needed for fisheries management. There is an urgent need for more interaction between biological oceanographers and fisheries scientists, particularly in the area of zooplankton grazing by larval fish.
History and present status of fisheries for marine fishes and invertebrates in the Strait of Georgia, British Columbia
Authors: Ketchen K. S. , Bourne N. , Butler T. H.
Published: September 2009

An historical account is given of the development of Strait of Georgia commercial fisheries (other than salmon) from their beginnings in the middle to late 19th century to the 1980s. Where possible, attempts were made to explain past fluctuation in abundance, especially to distinguish natural effects from those of fishing or socioeconomic origin. The review deals with commercial exploitation of herring (Clupea harengus pallasi), dogfish (Squalus acanthias), lingcod (Ophiodon elongatus), Pacific cod (Gadus macrocephalus), English sole (Parophrys vetulus), pollock (Theragra chalcogramma), hake (Merluccius productus), Dungeness crab (Cancer magister), shrimps (Pandalopsis dispar, Pandalus platyceros, P. jordani, P. hypsinotus and P. danae), oyster (Crassostrea gigas), butter clams (Saxidomus giganteus), little neck clams (Protothaca staminea), Manila clams (Tapes phillipinarum), geoduck clams (Panope generosa), and other invertebrates. Lingcod and the various shellfish species are also the object of recreational fisheries. Commercial landings in 1980 totalled 25 575 t with a landed value of over 20 million dollars. Over 57% of the weight landed and 70% of its landed value consisted of herring. Oysters, geoduck clams, Pacific cod, and Dungeness crabs were next in importance. We conclude that the future of the fishery will depend on policy regarding the coexistence of commercial and recreational components, the effectiveness of management measures, and probably on the success of controlling domestic and industrial pollution.
SOLUTION OVER-FIT CONTROL IN EVOLUTIONARY MULTIOBJECTIVE OPTIMIZATION OF PATTERN CLASSIFICATION SYSTEMS
Authors: RADTKE PAULO V. W. , WONG TONY , SABOURIN ROBERT
Published: September 2009

The optimization of many engineering systems is challenged by the solution over-fit to the data set used to evaluate potential solutions during the evolutionary process. The solution over-fit phenomenon is hard to detect and is especially prevalent in problems involving example-based training, such as pattern feature selection and pattern classifier design. For these applications, uncontrolled over-fit can lead to biased features being extracted and degraded classifier generalization abilities. This paper details the performance of a solution over-fit control strategy used in the multiobjective evolutionary optimization of a multileveled classification system. This control, embedded within a solution validation procedure, minimizes the over-fit effects without modifying the dominance relation used in the processing of candidate solutions. Extensive experimental analysis using multiobjective genetic and memetic algorithms demonstrates both the need and the efficiency of the proposed over-fit control for pattern classification systems optimization.
COMPREHENSIVE ANALYSIS FOR THE LOCAL FISHER DISCRIMINANT ANALYSIS
Authors: GAO JUNBIN , KWAN PAUL W. H. , HUANG XIAODI
Published: September 2009

Using local data information, the recently proposed local Fisher Discriminant Analysis (LFDA) algorithm18 provides a new way of handling the multimodal issues within classes where the conventional Fisher Discriminant Analysis (FDA) algorithm fails. Like the FDA algorithm (global counterpart), the LFDA suffers when it is applied to the higher dimensional data sets. In this paper, we propose a new formulation by which a robust algorithm can be formed. The new algorithm offers more robust results for higher dimensional data sets when compared with the LFDA in most cases. By extensive simulation studies, we have demonstrated the practical usefulness and robustness of our new algorithm in data visualization.
PLANT LEAF IDENTIFICATION BASED ON VOLUMETRIC FRACTAL DIMENSION
Authors: BACKES ANDRÉ RICARDO , CASANOVA DALCIMAR , BRUNO ODEMIR MARTINEZ
Published: September 2009

Texture is an important visual attribute used to describe the pixel organization in an image. As well as it being easily identified by humans, its analysis process demands a high level of sophistication and computer complexity. This paper presents a novel approach for texture analysis, based on analyzing the complexity of the surface generated from a texture, in order to describe and characterize it. The proposed method produces a texture signature which is able to efficiently characterize different texture classes. The paper also illustrates a novel method performance on an experiment using texture images of leaves. Leaf identification is a difficult and complex task due to the nature of plants, which presents a huge pattern variation. The high classification rate yielded shows the potential of the method, improving on traditional texture techniques, such as Gabor filters and Fourier analysis.
THEORETICAL STUDIES ON HEATS OF FORMATION OF PYRIDINE N-OXIDES USING DENSITY FUNCTIONAL THEORY AND COMPLETE BASIS METHOD
Authors: TANG ZHENG-XIN , LI XIAO-HONG , ZHANG RUI-ZHOU , ZHANG XIAN-ZHOU
Published: September 2009

The heats of formation (HOFs) for 11 pyridine N-oxide compounds are calculated by employing the hybrid density functional theory (B3LYP, B3PW91, B3P86, PBE1PBE) methods with 6-31G** basis set and ab initio CBS-4M method. It is demonstrated that the B3PW91 method is accurate to compute the reliable HOFs for pyridine N-oxide compounds. It is also noted that the HOF is the smallest for the pyridine N-oxide which has the substituent group on the para-position, such as 4-NC–c- C 5 H 4 NO , 4- H 2 NOC – C 5 H 4 N – O , and 4- HO 2 C –c- C 5 H 4 NO . In addition, we think that the HOF of 2- HO 2 C –c- C 5 H 4 NO is much larger than that of 3- HO 2 C –c- C 5 H 4 NO and 4- HO 2 C –c- C 5 H 4 NO , which may be the result of intramolecular hydrogen bond formation and further measurements are needed to reexamine the HOFs for 2- HO 2 C –c- C 5 H 4 NO , 3- HO 2 C –c- C 5 H 4 NO , and 4- HO 2 C –c- C 5 H 4 NO .
COMPUTATIONAL STUDY FOR BINDING OF OSCILLARIN TO HUMAN α-THROMBIN
Authors: WU EMILIA L. , HAN KELI , ZHANG JOHN Z. H.
Published: September 2009

Quantum mechanical calculation and molecular dynamics simulation have been carried out to study binding of Oscillarin (OSC), an antithrombotic marine natural product to human α-thrombin. The binding interaction energies between the inhibitor and individual protein fragments are calculated using a combination of HF and DFT methods. Study shows that the strong binding of OSC to Asp189, Ser214, Trp215, Gly216, and Gly219 is the primary mechanism of drug binding to thrombin. The individual residue–ligand interaction energies provide detailed quantitative information about specific residue interaction with the ligand that should be extremely useful to our understanding of the molecular nature of protein–ligand binding.
REAL-TIME APPROACH TO TIME-DEPENDENT DENSITY-FUNCTIONAL THEORY IN THE LINEAR AND NONLINEAR REGIME
Authors: MUNDT MICHAEL
Published: September 2009

The linear and nonlinear response of Si 4 and Na 4 to an external perturbation is investigated in the framework of time-dependent density-functional theory. The time-dependent Kohn–Sham equations, which are the central equations in this approach, are solved in real space and real time. A parallelized implementation to solve these nonlinear, one-particle Schrödinger equations is presented. In contrast to Na 4, Si 4 shows high-harmonic generation far beyond the cut-off predicted by the quasiclassical model and predictions for extended systems.
AB INITIO INVESTIGATIONS OF THE RADICAL–RADICAL REACTION: N (4S) + NCO (X2Π)
Authors: ZUO MING-HUI , LIU HUI-LING , HUANG XU-RI , SUN CHIA-CHUNG , TANG AU-CHIN
Published: September 2009

The reaction of N (4S) radical with NCO (X2Π) radical has been studied theoretically using density functional theory and ab initio quantum chemistry method. The triplet electronic state [ N 2 CO ] potential energy surface (PES) is calculated at the G3B3 and CCSD(T)/aug-cc-pVDZ//B3LYP/6-311++G(d,p) levels of theory. All the energies of the transition states and isomers in the pathway RP1 are lower than that of the reactants; the rate of this pathway should be very fast. Thus, the novel reaction N + NCO can proceed effectively even at low temperatures and it is expected to play a role in both combustion and interstellar processes. On the basis of the analysis of the kinetics of all pathways through which the reactions proceed, we expect that the competitive power of reaction pathways may vary with experimental conditions for the title reaction.
EXPANSION FORMULAE FOR ONE- AND TWO-CENTER CHARGE DENSITIES OVER COMPLETE ORTHONORMAL SETS OF EXPONENTIAL TYPE ORBITALS AND THEIR USE IN EVALUATION OF MULTICENTER–MULTIELECTRON INTEGRALS
Authors: GUSEINOV I. I.
Published: September 2009

The series expansion formulae are established for the one- and two-center charge densities over complete orthonormal sets of Ψα-exponential type orbitals (Ψα-ETO α = 1,0,-1,-2,…) introduced by the author. Three-center overlap integrals of Ψα appearing in these relations are expressed through the two-center overlap integrals between Ψα-orbitals. The general formulae obtained for the charge densities are utilized for the evaluation of arbitrary multicenter–multielectron integrals occurring when the complete orthonormal sets of Ψα-ETO are used as basis functions in the Hartree–Fock–Roothaan and explicitly correlated methods. The relationships for charge densities and multicenter–multielectron integrals obtained are valid for the arbitrary quantum numbers, screening constants, and location of Ψα-orbitals.
ELECTRON TOPOLOGICAL AND ENERGETIC STUDY OF THE INTERMOLECULAR HALOGEN BONDING INTERACTIONS IN COMPLEXESH2O⋯M(M=F2,ClF,ANDCF4)
Authors: LI HAI-BEI , BAI YU BIN , TIAN SHAN XI , YANG JINLONG
Published: September 2009

The halogen bonding complexes H2O ⋯ M ( M = F2, ClF , and CF4) in comparison with the hydrogen bonding H2O ⋯ HF complex are studied by high-level ab initio calculations and electron topological atoms-in-molecules (AIM) analyses. The basis set superposition error corrections are important to predict if the structures are in good agreement with the experimental results. Both the CCSD(T)/aug-cc-pVTZ calculations and the AIM analyses indicate a interaction strength order: H2O ⋯ HF > H2O ⋯ ClF ⋯ H2O ⋯ F2⋯ H2O ⋯ CF4, with the interaction energies –7.91, –4.16, –1.11, and –1.05 kcal/mol, respectively. The symmetry-adapted perturbation theory analyses have been carried out towards understanding of the nature of the halogen bonding interactions in the complexes H2O ⋯ M ( M = F2, ClF , and CF4), where the exchange energies are the predominant repulsive components. For the complexes involving polar monomers, the hydrogen bonding H2O ⋯ HF and the halogen bonding H2O ⋯ ClF , the largest attractive contributions are the electrostatic energies. However, in H2O ⋯ F2and H2O ⋯ CF4, the attractive dispersion energies become more important, and the induction energy in the former complex is a little higher than that in the latter. In contrary to the red-shifts of H – F , Cl – F , and F – F bond stretching vibrational frequencies in the complexes H2O ⋯ M ( M = HF , ClF , and F2), the blue-shifts are predicted for C – F bonds neighboring water in H2O ⋯ CF4.
DENSITY FUNCTIONAL THEORY/TIME-DEPENDENT DENSITY FUNCTIONAL THEORY STUDY ON THE STRUCTURES AND SOLVENT EFFECTS ON THE ELECTRONIC SPECTRA OF Ru(II) POLYPYRIDYL COMPLEXES: [Ru(bpy)2(L)]2+ (L = CNOIP, HPIP, DPPZ, TAPIP)
Authors: LU ZHUAN , ZHANG QIANLING , XU YANGSEN , WANG MINGLIANG , LIU JIANHONG
Published: September 2009

The structures and solvent dependence of electronic spectra of four Ru ( II ) polypyridyl complexes: [ Ru ( bpy )2 CNOIP ]2+, bpy = 2,2-bipyridine and CNOIP = 2-(2-chloro-5-nitrophenyl)imidazo[4,5-f][1,10]phenanthroline (Ru-1); [ Ru ( bpy )2 HPIP ]2+, HPIP = 2-(2-hydroxyphenyl) imidazo[4,5-f][1,10]phenanthroline ( Ru -2); [ Ru ( bpy )2 DPPZ ]2+, DPPZ = dipyrido[3,2:a-2′,3′:c]-phenazine ( Ru -3); [ Ru ( bpy )2 TAPIP ]2+, TAPTP = 4,5,9,18-tetraazaphenanthreno-[9,10-b]triphenylene ( Ru -4) have been carried out by density functional theory/time-dependent density functional theory in vacuum and nine solvents are described by the conductor-like polarized continuum model. The calculated results show that the solvent has a strong effect on the electron distribution of molecular orbitals and character of charge transfer. In water, the simulated absorption spectra (λmax) are in accordance with experimental data. The computational results also indicate the electronic spectra of Ru ( II ) polypyridyl complexes: [ Ru ( bpy )2( L )]2+ is very sensitive to the intercalative ligands L = CNOIP, HPIP, DPPZ, TAPIP in the presence of solvent. It was noted that the trend of transition intensity of complexes strongly depends on the polarity of solvents. In the present polar solvents, the transition intensity trend of Ru -4 > Ru -1 > Ru -2 > Ru -3 was obtained, but in the case of nonpolar solvents, the transition intensity trend is Ru -4 > Ru -3 > Ru -1 > Ru -2. Among the four polypyridyl complexes, [ Ru ( bpy )2 TAPIP ]2+( Ru -4) exhibits the strongest oscillator strength in all nine solvents.
INTERACTION OF THE TAUTOMERIC STATES OF HISTIDINE WITHCuANDZnMETAL IONS – A THEORETICAL STUDY
Authors: ABIRAM A. , KOLANDAIVEL P.
Published: September 2009

A density functional study on the interaction of Cu2+and Zn2+metal ions at the predominant positions of Nτ– H and Nπ– H histidine tautomers has been performed. The fully optimized energy of the isolated histidine tautomers at B3LYP/6-311++G** level of theory depicts Nτ– H tautomer to be much stable compared to that of the Nπ– H tautomer. The interaction of metal ions forms bidentate and tridentate complexes with Nτ– H tautomer, while it is absent in the case of Nπ– Htautomer emphasizing the role of former in structural determination of liganated proteins. The Zn2+ion induces a barrier-free proton transfer when interacted at the carbonyl position of Nτ– H histidine tautomer necessitating the tautomer to be in the zwitterionic form for complexation. The thermodynamical analysis predicts a blue shift in the NH and CO stretching vibrational frequencies and suggests Nτ– H tautomer to be best suitable for Cu2+and Zn2+ion interactions. The topological and charge transfer studies in concert with frontier molecular orbital (FMO) analysis confirm the covalent interaction, validating the findings based on the geometrical data.
THE ROLE OF SUBSTRATE IN PACKING STRUCTURES OF SEXITHIOPHENES ON AG (111) SURFACE: MOLECULAR DYNAMICS SIMULATIONS AND QUANTUM CHEMICAL CALCULATIONS
Authors: WEN JIN , MA JING
Published: September 2009

Packing structures and orientation of sexithiophene (6T) molecules on Ag (111) surface are investigated by molecular dynamics (MD) simulations and quantum chemical calculations. Both the cluster and the slab models are employed. The density functional theory and molecular mechanism calculations demonstrate a weak physisorption and little site-preference in thiophene/ Ag (111) system. The MD simulations show that in the first layer close to the surface, the nearly coplanar 6T strips lie parallel with long axes deviating from [Formula: see text] direction about 20° – 30° and 75° – 90°. The average adsorption height of the monolayer is about 3.2 Å with most of the sulfur atoms in thienyl rings sitting on the bridge site of Ag (111) surface. The 6T molecules tend to take tilted orientations when they are far away from the surface. The packing structures of 6T layers deposited on the surface resulted from the competition between the molecule–substrate and intermolecular interactions.
COMPUTER SIMULATION OF LIQUID–VAPOR INTERFACIAL TENSION: LENNARD-JONES FLUID AND WATER REVISITED
Authors: WANG JUN , ZENG XIAO CHENG
Published: September 2009

We review several commonly used simulation methods for computing liquid–vapor surface tension and associated theoretical treatments of the long-range correction for inhomogeneous systems. Prototype model systems considered in this review are the Lennard-Jones (LJ) fluid and the SPC/E model water. In addition, we examine a variety of factors that can affect calculation of the surface tension γ via the mechanical approach (i.e. using either KB or IK method). It is found that for the LJ fluid, the size of simulation box and the number of particles in the system can have notable effects on the computed surface tension. For SPC/E water, the Ewald parameters can influence computed surface tensions (γ) as well, e.g., very small Ewald parameters tend to overestimate γ. It is also found that the IK method consistently gives γ that are 0.6 - 0.9 mN/m greater than γ computed based on the KB method. When computing the first reciprocal–space contribution to the surface tension, the Ghoufi's strategy gives rise to more sensible profile of pressure difference PN(z)-PT(z) than the Alejandre's strategy although both strategies result in nearly the same average surface tension through the integration of PN(z)-PT(z).
QUANTUM CODES FROM CYCLIC CODES OVER FINITE RING
Authors: QIAN JIANFA , MA WENPING , GUO WANGMEI
Published: September 2009

A new method to obtain self-orthogonal codes over finite field F2 is presented. Based on this method, we provide a construction for quantum error-correcting codes starting from cyclic codes over finite ring R = F2 + uF2. As an example, we present infinite families of quantum error-correcting codes which are derived from cyclic codes over the ring R = F2 + uF2.
FERMI TRANSPORT OF SPINORS AND FREE QED STATES IN CURVED SPACETIME
Authors: CANARUTTO DANIEL
Published: September 2009

Fermi transport of spinors can be precisely understood in terms of two-spinor geometry. By using a partly original, previously developed treatment of two-spinors and classical fields, we describe the family of all transports, along a given one-dimensional timelike submanifold of spacetime, which yield the standard Fermi transport of vectors. Moreover, we show that this family has a distinguished member, whose relation to the Fermi transport of vectors is similar to the relation between the spinor connection and spacetime connection. Various properties of the Fermi transport of spinors are discussed, and applied to the construction of free electron states for a detector-dependent QED formalism introduced in a previous paper.
SUPERSYMMETRIC SIGMA MODELS AND HARMONIC SUPERFUNCTIONS
Authors: MUÑOZ-MASQUÉ JAIME , ANTONIO VALLEJO JOSÉ
Published: September 2009

We study the relation between the Laplacian associated to an odd metric on a supermanifold and harmonic superfunctions, through the application of the calculus of variations to a supersymmetric sigma model.
A MECHANICS FOR THE RICCI FLOW
Authors: ABRAHAM S. , FERNÁNDEZ DE CÓRDOBA P. , ISIDRO JOSÉ M. , SANTANDER J. L. G.
Published: September 2009

We construct the classical mechanics associated with a conformally flat Riemannian metric on a compact, n-dimensional manifold without boundary. The corresponding gradient Ricci flow equation turns out to equal the time-dependent Hamilton–Jacobi equation of the mechanics so defined.
VENEZIANO AMPLITUDES, SPIN CHAINS, AND STRING MODELS
Authors: KHOLODENKO ARKADY L.
Published: September 2009

In a series of recently published papers, we reanalyzed the existing treatments of Veneziano and Veneziano-like amplitudes and the models associated with these amplitudes. In this work, we demonstrate that the already obtained new partition function for these amplitudes can be exactly mapped into that for the Polychronakos–Frahm spin chain model. This observation allows us to recover many of the existing string-theoretic models, including the most recent ones.
LIQUID CRYSTAL BASED ROTATING ORTHOGONAL POLARIZATION IMAGING SYSTEM
Authors: ZHU QUN , STOCKFORD IAN M. , CROWE JOHN A. , MORGAN STEPHEN P.
Published: September 2009

Rotating orthogonal polarization imaging provides images of the polarization properties of scattering media which are free from surface reflections. Previously the technique has been demonstrated using manually rotated Glan–Thompson polarizers to control and analyze the polarization state of the light entering and emerging from the tissue. This paper describes a system that performs these functions using liquid crystal retarders. The system is tested using a polarizing target embedded within a scattering medium and is compared with Monte Carlo simulations. The results compare well with those obtained with manual rotation of polarizers. The liquid crystal based approach has advantages over the previous system in terms of ease of use, speed, and repeatability and is therefore an important step towards taking the technique into routine clinical use.
Z-SCAN TECHNIQUE FOR MEASUREMENT OF TOTAL CHOLESTEROL AND TRIGLYCERIDES IN BLOOD
Authors: DHINAA A. N. , PALANISAMY P. K.
Published: September 2009

The measurement of cholesterol and triglycerides in blood by Z-scan technique is proposed. The nonlinear refractive index of cholesterol and triglycerides was found to vary linearly with concentration. Hence by calculating the nonlinear refractive index it is possible to measure their concentration in the sample. These measured values are found in equivalence with conventional colorimetric method.