bluuebunny/crossref_metadata_2025 huggingface dataset:
Maternal Depression: A Global Threat to Children’s Health, Development, and Behavior and to Human Rights
Authors: Wachs Theodore D. , Black Maureen M. , Engle Patrice L.
Published: March 2009

ABSTRACT—
Depressive disorders are a common source of disability among women. In addition to the economic and human costs of maternal depression, children of depressed mothers are at risk for health, developmental, and behavioral problems. Although most of the research examining the evidence and intergenerational aspects of maternal depression has been conducted in high‐income countries, recent evidence suggests that rates of maternal depression may be higher in low‐ and middle‐income countries, where nearly 90% of the world’s children live. This review examines the evidence from low‐ and middle‐income countries that links maternal depression with children’s health, development, and behavior. We present recommendations for future policies and intervention programs related to maternal depression and examine how maternal depression affects the rights of millions of children living in these countries.
Social Cognitive Development: A New Look
Authors: Olson Kristina R. , Dweck Carol S.
Published: March 2009

ABSTRACT—
This article showcases exciting new work in the burgeoning area of social cognitive development, particularly work that uses the methods of cognitive development to illuminate socially relevant mental representations and mental processes. The authors focus on key aspects of children’s emerging social judgments and social representations, examining their judgments of goodness, their evaluations of similar and dissimilar others, and their representations of social relationships. The authors also show how researchers using methods from other fields, such as adult social cognition, comparative psychology, and neuroscience, are making important new contact with social cognitive development to shed light on the origins and nature of social representations and social cognitive processes.
Development in Children and Adolescents Whose Mothers Have Borderline Personality Disorder
Authors: Macfie Jenny
Published: March 2009

ABSTRACT—
A mother’s mental illness may have a profound effect on her child’s development, including an increased risk of the child developing the same disorder. From a developmental psychopathology perspective, offspring provide an opportunity to examine pathways to disorder versus resilience. Borderline personality disorder (BPD) is a severe disorder diagnosed in early adulthood involving stormy relationships, an unstable sense of identity, and self destructive behavior. Interestingly, the domains of dysfunction are conceptually similar to developmental tasks in early childhood reworked in adolescence: attachment, self development, and self‐regulation. Early deviation may increase the risk for later disorder. There are 5 empirical studies of children whose mothers have BPD, 2 conducted from a developmental perspective. This article proposes a theoretical framework and an innovative methodology with which to extend this research and suggests an intervention to bring development back on track if necessary.
Debating the Impact of Television and Video Material on Very Young Children: Attention, Learning, and the Developing Brain
Authors: Courage Mary L. , Setliff Alissa E.
Published: March 2009

ABSTRACT—The debate about the potential of television and video material to enhance or diminish cognitive development in infants and toddlers has been complicated by speculation regarding the relation between early exposure to these media and the developing brain. Those on both sides of the debate draw on findings from developmental and neuroscience literatures to make explicit or implicit arguments that video experience during the first 2 or 3 years can have a unique and powerful impact on learning that cannot be readily duplicated or undone outside this sensitive period of development. This article tries to put such speculation into perspective by considering it within the framework ofW. T. Greenough, J. T. Black, and C. S. Wallace’s (1987)distinction between experience‐expectant and experience‐dependent plasticity. Data from infant‐learning and attention research are used to illustrate how this distinction illuminates both sides of the debate.
The Response to Intervention Instructional Model: Some Outcomes From a Large‐Scale Implementation in Reading First Schools
Authors: Torgesen Joseph K.
Published: March 2009

ABSTRACT—
The Reading First program in Florida has attempted to implement the response to intervention instructional model in a large number of schools. This has involved (a) increasing the quality of classroom instruction, (b) monitoring student response to instruction with frequently administered progress monitoring measures, and (c) providing tailored interventions to students who are not making adequate progress. Over 3 years of implementation in 318 schools, rates of identification of students with learning disabilities (LDs) have dropped dramatically. Percentages of students who actually have serious reading difficulties have also dropped during this period, although not as dramatically as for rates of LD identification. It is possible that LD identification rates in Grades K–3 are lower because teachers and schools are exploring other intervention options before referring for special education. Implications of this possibility for timeliness of LD diagnosis are discussed.
Polymorphic microsatellite DNA markers in the mangrove crabUcides cordatus(Brachyura: Ocypodidae)
Authors: BRITTO FÁBIO B. , DINIZ FÁBIO M. , PATERSON IAN , BENTZEN PAUL
Published: March 2009

The isolation and characterization of the first polymorphic microsatellite markers for the mangrove crabUcides cordatusare described. The number of alleles at each locus ranged from three to 25, mean of nine alleles, in 46 crabs captured in two Brazilian mangroves. The markers averaged high levels of observed (0.709  ±  0.183) and expected (0.716  ±  0.170) heterozygosities. Departures from Hardy–Weinberg equilibrium were observed at two loci. Linkage disequilibrium tests were not significant and no evidence of null alleles was detected. All these microsatellite loci are expected to be useful in estimating fine‐scale population processes of this valuable mangrove species currently subjected to excessive fishing efforts.
Globularia anatolica sp. nov. (Globulariaceae) from the Honaz Mountain National Park, southwest Turkey
Authors: Duran Ahmet , Çetin Özlem , Öztürk Meryem
Published: March 2009

A new species, Globularia anatolica A. Duran, Ö. Çetin & M. Öztürk (Globulariaceae) is described and illustrated from southwest Turkey. The species grows on eroded gypsum slopes and in open Pinusbrutia Ten. forest in the Honaz Mountain National Park (C2 Denizli province). It is closely related to G. sintenisii Hausskn. & Wettst., an endemic species confined to southwest Anatolia. Diagnostic morphological characters of Globularia anatolica are discussed and presented as a key to Turkish Globularia. It is suggested that the new species should be regarded as ‘Critically Endangered’ (CR) according to the IUCN criteria. In addition, the biogeography of the Honaz Mountain is briefly outlined.
Optimal Tracking Using Magnetostrictive Actuators Operating in Nonlinear and Hysteretic Regimes
Authors: Oates William S. , Smith Ralph C.
Published: March 2009

Many active materials exhibit nonlinearities and hysteresis when driven at field levels necessary to meet stringent performance criteria in high performance applications. This often requires nonlinear control designs to effectively compensate for the nonlinear, hysteretic, field-coupled material behavior. In this paper, an optimal control design is developed to accurately track a reference signal using magnetostrictive transducers. The methodology can be directly extended to transducers employing piezoelectric materials or shape memory alloys due to the unified nature of the constitutive model employed in the control design. The constitutive model is based on a framework that combines energy analysis at lattice length scales with stochastic homogenization techniques to predict macroscopic material behavior. The constitutive model is incorporated into a finite element representation of the magnetostrictive transducer, which provides the framework for developing the finite-dimensional nonlinear control design. The control design includes an open loop nonlinear component computed off-line with perturbation feedback around the optimal state trajectory. Estimation of immeasurable states is achieved using a Kalman filter. It is shown that when operating in a highly nonlinear regime and as the frequency increases, significant performance enhancements are achieved relative to conventional proportional-integral control.
Realization-Preserving Structure and Order Reduction of Nonlinear Energetic System Models Using Energy Trajectory Correlations
Authors: Ersal Tulga , Fathy Hosam K. , Stein Jeffrey L.
Published: March 2009

Previous work by the authors developed algorithms for simplifying the structure of a lumped dynamic system model and reducing its order. This paper extends this previous work to enable simultaneous model structure and order reduction. Specifically, it introduces a new energy-based metric to evaluate the relative importance of energetic connections in a model. This metric (1) accounts for correlations between energy flow patterns in a model using the Karhunen–Loève expansion; (2) examines all energetic connections in a model, thereby assessing the relative importance of both energetic components and their interactions, and enabling both order and structural reduction; and (3) is realization preserving, in the sense of not requiring a state transformation. A reduction scheme based on this metric is presented and illustrated using a simple example. The example shows that the proposed method can successfully concurrently reduce model order and structure without requiring a realization change, and that it can provide an improved assessment of the importance of various model components due to its correlation-based nature.
Conditions of Parametric Resonance in Periodically Time-Variant Systems With Distributed Parameters
Authors: Lee Yong-Kwan , Chechurin Leonid S.
Published: March 2009

Theoretical analysis of the stability problem for the control systems with distributed parameters shall be given. The approach to the analysis of such systems can be composed of two parts. First, the distributed parameter element is modeled by a frequency response function. Second, approximate conditions of parametric resonance are derived by a method of stationarization (describing functions of time-variant elements). The approach is illustrated by two examples. One is a robot-manipulator arm (distributed mechanical parameter system) controlled by a controller with a modulator/demodulator cascade (time-varying element). Another is an electromechanical transformer that consists of a constant current motor and a synchronous generator. Inductance between stator windings and the rotor of the synchronous generator serves as a periodical time-varying parameter, and a long electrical line plays the role of an element with distributed parameters. In both examples, dangerous (in terms of the first parametric resonance) regions for time-varying parameter are obtained theoretically and compared with simulation experiment.
Robust Negative Input Shapers for Vibration Suppression
Authors: Vaughan Joshua , Yano Aika , Singhose William
Published: March 2009

Input shaping is a control method that limits motion-induced oscillation in vibratory systems by intelligently shaping the reference command. As with any control method, the robustness of input shaping to parameter variations and modeling errors is an important consideration. For input shaping, there exists a fundamental compromise between robustness to such errors and system rise time. For all types of shapers, greater robustness requires a longer duration shaper, which degrades rise time. However, if a shaper is allowed to contain negative impulses, then the shaper duration may be shortened with only a small cost of robustness and possible high-mode excitation. This paper presents a thorough analysis of the compromise between shaper duration, robustness, and possible high-mode excitation for several negative input-shaping methods. In addition, a formulation for specified negative amplitude, specified insensitivity shapers is presented. These shapers provide a continuous spectrum of solutions for the duration/robustness/high-mode excitation trade-off. Experimental results from a portable bridge crane verify the theoretical predictions.
Robust Design of Inertial Measurement Units Based on Accelerometers
Authors: Qin Zhongkai , Baron Luc , Birglen Lionel
Published: March 2009

This paper presents a robust design scheme for an inertial measurement unit (IMU) composed only of accelerometers. From acceleration data measured by a redundant set of accelerometers, the IMU proposed in this paper can estimate the linear acceleration, angular velocity, and angular acceleration of the rigid-body to which it is attached. The robustness of our method to the uncertainty of the locations of the sensors and the measurement noise is obtained through redundancy and optimal configuration of the onboard sensors. In addition, the fail-diagnostics and fail-safe issues are also addressed for reliable operation.
Robust Stabilization and Disturbance Rejection for a Class of Hybrid Linear Systems Subject to Exponential Uncertainty
Authors: Long Fei , Li Changlin , Cui Changzheng , Fei Shumin
Published: March 2009

In this paper, we address the problem of robust stabilization and disturbance rejection for a class of hybrid linear systems subject to exponential uncertainties. By using Taylor series approximation and convex polytope technique, the exponentially uncertain hybrid linear system is transformed into an equivalent hybrid polytopic model subject to norm bounded uncertainty. For such equivalent hybrid linear model, we design its switching strategy and associated state feedback controllers so that such model is asymptotically stable with H∞ disturbance attenuation based on multiple Lyapunov function technology and linear matrix inequality (LMI) approach.
Modeling the Vacuum Circuit of a Pneumatic Valve System
Authors: Galindo J. , Climent H. , Guardiola C. , Doménech J.
Published: March 2009

The aim of this article is to present the theoretical and experimental work related to the vacuum system used for controlling the actuation of pneumatic valves in internal combustion engines in order to obtain a physical model of this system. In this context, these valves control the turbocharger operation in a two-stage sequential turbocharged diesel engine. With the purpose of providing the model with information, several characterization tests of the elements that integrate the vacuum system were performed. Related to the theoretical contents, two models of the vacuum system were developed and compared, either by using a 1D or a 0D approach. Within the experimental section the obtained instantaneous pressure in the actuator chamber of four air valves and two storage reservoirs of the circuit are measured and compared with the modeling results. Since the simulations show good agreement when comparing the instantaneous pressure evolutions and valve movement with the experimental data, the model can be used to predict the behavior of the vacuum system. Finally, the model is used to optimize the transient turbocharger sequential operation under real engine running conditions. The simulation results predict with accuracy the measurements acquired in an engine test bench. Therefore a consistent methodology has been established in order to reproduce the vacuum system behavior and can be used as a designing tool for complex applications devoted to engine controlling tasks.
Modeling, Experimentation, and Simulation of an Air-Over-Hydraulic Brake System
Authors: Xiong Xicheng , Wei Jianhua , Chen Jian
Published: March 2009

This paper deals with the development and validation of an analytical dynamic model of an air-over-hydraulic (AOH) brake system that is widely used on loaders. The AOH system is broken into five simple and cascaded subsystems, pneumatic circuit, air-hydraulic actuator, brake line, wheel cylinder, and disk brake. Pneumatic, hydraulic, and mechanical dynamics are taken care of in each subsystem. The determination of model coefficients is introduced in detail. Many experiments are performed on an experimental setup of the real AOH system on a loader and the experimental data are compared with the simulation results. Preliminary analysis shows that the simulation results are in good agreement with the experimental data. Other researchers in the areas of brake systems in construction machinery would find the model useful for similar system modeling and analysis
Electrooxidation and determination of sulfite in ethanol–water solutions using poly-Cu(II)-tetrakis(x-aminophenyl)porphyrin/glassy carbon modified electrodes
Authors: Bravo Paz , Chen Yo-Ying , Ramirez Galo , Canales Maria J. , Matsuhiro Betty , Mendoza Leonora , Isaacs Mauricio , García Macarena , Arevalo Maria C. , Aguirre Maria J.
Published: March 2009

A comparison is made of the behavior of three Cu(II)-porphyrins (with the amino substituents in different positions on the periphery of the ligand) electropolymerized on glassy carbon electrodes in HCl as solvent. The electropolymerized films show a certain degree of demetallation but the Cu amount of porphyrin in each case is sufficient to catalyze the oxidation of sulfite and hydrogensulfite in ethanol–water solutions. The ligands of the porphyrins are almost inactive in the electrocatalysis of the sulfite. The oxidation processes are favored at low scan rates. The foot of the oxidation waves depends on the positions. The most active porphyrin bears the substituents with the amino groups in para position, the oxidation occurring at low positive potentials. All the modified electrodes can be used as amperometric sensors for sulfite; they show linear relationships between the current and sulfite concentration in the range in which sulfites are present in red wines. The modified electrodes are stable and all of them promote the oxidation of sulfite to sulfate.
Synthesis of 3′-O-(2-cyanoethyl)-2′-deoxythymidine-5′-phosphate as a model compound for evaluation of cyanoethyl cleavage
Authors: Keller Angelika C. , Serva Saulius , Knapp Diana C. , Kwiatkowski Marek , Engels Joachim W.
Published: March 2009

An essential and challenging task during the development of our sequencing-by-synthesis (SBS) technique is the evaluation of efficient cyanoethyl (CE) cleavage conditions. For this purpose 3′-O-(2-cyanoethyl)-2′-deoxythymidine-5′-phosphate as a model compound as well as a short DNA oligomer bearing the CE function as terminal group were synthesized and used for various deprotection experiments. As it is already known for 2′-O-CE-protected RNA oligonucleotides, the CE function can be cleaved with tetrabutylammonium fluoride (TBAF) in THF. Indeed, by using 3′-O-(2-cyanoethyl)-2′-deoxythymidine-5′-phosphate as a simple model compound for cleavage tests, we found out that the 3′-O-CE function is quantitatively cleaved with 1 M TBAF in THF. However, the CE group is also cleaved by other small bases like hydroxy groups under alkaline conditions. The CE cleavage with TBAF in THF gives the fastest and quantitative removal of the CE group under mild conditions for our sequencing-by-synthesis (SBS) application. The efficient removal of the 3′-CE group is crucial for the proof-of-principle of our SBS approach using dye-labeled 3′-CE-blocked dNTPs, which is currently under investigation. Herein we describe the application of 3′-O-(2-cyanoethyl)-2′-deoxythymidine-5′-phosphate as model compound for the development of reversible terminators for the SBS technique. Furthermore we suggest that nucleoside phosphates bearing any removable 3′-modification might be suitable model compounds for cleavage studies in a heterogeneous environment comparable to an oligonucleotide/ aprotic solvent system.
Partial molar volume of methanol in water: Effect of polarizability
Authors: Moučka Filip , Nezbeda Ivo
Published: March 2009

The available pairwise additive intermolecular interaction models used so far in simulations in combination with common combining rules do not seem to be able to reproduce the most distinct feature of aqueous solutions of alcohols, the minimum of the partial molar volume at low alcohol concentrations. Nonetheless, this fundamental failure seems to have been paid little attention to, partly because of very high requirements for accuracy and, hence, CPU time of simulations. As an attempt to go beyond empirical combining rules and account in a more physical and yet simple way for the cross interactions, a feasibility study has been undertaken using a polarizable model of water in molecular simulations of the water–methanol mixture at ambient conditions. It turns out that the inclusion of polarizability may qualitatively change the behavior of the mixture bringing the result in agreement with experiment.
Effects of 10 Hz rTMS on the Neural Efficiency of Working Memory
Authors: Preston Gilbert , Anderson Erik , Silva Claudio , Goldberg Terry , Wassermann Eric M.
Published: March 2009

Working memory (WM) has been described as short-term retention of information that is no longer accessible in the environment, and the manipulation of this information for subsequent use in guiding behavior. WM is viewed as a cognitive process underlying higher-order cognitive functions. Evidence supports a critical role for PFC in mediating WM performance. Studies show psychomotor processing speed and accuracy account for considerable variance in neural efficiency (Ne). This study compared the relative effects of active and sham 10 Hz rTMS applied to dorsolateral prefrontal cortex (DLPFC) on indices of Ne in healthy participants performing a WM paradigm that models the association between WM load and task behavior [Sternberg, S. High-speed scanning in human memory. Science, 153, 652–654, 1966]. Previous studies identified a relationship between diminished Ne and impaired WM across a broad array of clinical disorders. In the present study, the authors predicted there would be a main effect of stimulation group (STM) on accuracy (SCR) and processing speed (RT), hence, Ne. We observed a main effect of STM for RT without an effect on SCR; even so, there was a robust effect of STM on Ne.
Monitoring Coordination during Bimanual Movements: Where Is the Mastermind?
Authors: Duque Julie , Davare Marco , Delaunay Ludovic , Jacob Benvenuto , Saur Ralf , Hummel Friedhelm , Hermoye Laurent , Rossion Bruno , Olivier Etienne
Published: March 2009

One remarkable aspect of the human motor repertoire is the multitude of bimanual actions it contains. Still, the neural correlates of coordinated movements, in which the two hands share a common goal, remain debated. To address this issue, we designed two bimanual circling tasks that differed only in terms of goal conceptualization: a “coordination” task that required movements of both hands to adapt to each other to reach a common goal and an “independent” task that imposed a separate goal to each hand. fMRI allowed us to pinpoint three areas located in the right hemisphere that were more strongly activated in the coordination condition: the superior temporal gyrus (STG), the SMA, and the primary motor cortex (M1). We then used transcranial magnetic stimulation (TMS) to disrupt transiently the function of those three regions to determine their causal role in bimanual coordination. Right STG virtual lesions impaired bimanual coordination, whereas TMS to right M1 enhanced hand independence. TMS over SMA, left STG, or left M1 had no effect. The present study provides direct insight into the neural correlates of coordinated bimanual movements and highlights the role of right STG in such bimanual movements.
Blindsight Mediated by an S-Cone-independent Collicular Pathway: An fMRI Study in Hemispherectomized Subjects
Authors: Leh Sandra E. , Ptito Alain , Schönwiesner Marc , Chakravarty Mallar M. , Mullen Kathy T.
Published: March 2009

The purpose of our study was to investigate the ability to process achromatic and short-wavelength-sensitive cone (S-cone)-isolating (blue–yellow) stimuli in the blind visual field of hemispherectomized subjects and to demonstrate that blindsight is mediated by a collicular pathway that is independent of S-cone inputs. Blindsight has been described as the ability to respond to visual stimuli in the blind visual field without conscious awareness [Weiskrantz, L., Warrington, E. K., Sanders, M. D., & Marshall, J. Visual capacity in the hemianopic field following a restricted occipital ablation. Brain, 97, 709–728, 1974]. The roles of the subcortical neural structures in blindsight, such as the pulvinar and the superior colliculus, have been debated and an underlying neural correlate has yet to be confirmed. Using fMRI, we tested the ability to process visual stimuli that isolated the achromatic and short-wavelength-sensitive (S-)-cone pathways in three subjects: one control subject, one hemispherectomized subject with blindsight, and one hemispherectomized subject without blindsight. We demonstrated that (1) achromatic and S-cone-isolating stimuli presented to the normal visual hemifield of hemispherectomized subjects and to both visual hemifields of the control subject activated contralateral visual areas (V1/V2), as expected; (2) achromatic stimulus presentation but not S-cone-isolating stimulus presentation to the blind hemifield of the subject with blindsight activated visual areas FEF/V5; (3) whereas the cortical activation of the control subject was enhanced by an additional stimulus (achromatic and S-cone isolating) presented in the contralateral visual field, activation pattern of the subject with blindsight was enhanced by achromatic stimuli only. We conclude that the human superior colliculus is blind to the S-cone-isolating stimuli, and blindsight is mediated by an S-cone-independent collicular pathway.
Two Modes of North American Drought from Instrumental and Paleoclimatic Data*
Authors: Woodhouse C. A. , Russell J. L. , Cook E. R.
Published: March 2009

Droughts, which occur as a part of natural climate variability, are expected to increase in frequency and/or severity with global climate change. An improved understanding of droughts and their association with atmospheric circulation will add to the knowledge about the controls on drought, and the ways in which changes in climate may impact droughts. In this study, 1) major drought patterns across the United States have been defined, 2) the robustness of these patterns over time using tree-ring-based drought reconstructions have been evaluated, and 3) the drought patterns with respect to global atmospheric pressure patterns have been assessed. From this simple assessment, it is suggested that there are two major drought patterns across North America, which together account for about 30% of the total variance in drought patterns—one resembles the classic ENSO teleconnection, and the other displays an east–west drought dipole. The same two patterns are evident in the instrumental data and the reconstructed drought data for two different periods, 1404–2003 and 900–1350. The 500-mb circulation patterns associated with the two drought patterns suggest that the controls on drought may come from both Northern Hemisphere and tropical sources. The two drought patterns, and presumably their associated circulation patterns, vary in strength over time, indicating the combined effects of the two patterns on droughts over the past millennium.
Interannual Tasmanian Rainfall Variability Associated with Large-Scale Climate Modes
Authors: Hill Khalia J. , Santoso Agus , England Matthew H.
Published: March 2009

Interannual rainfall variability over Tasmania is examined using observations and reanalysis data. Tasmanian rainfall is dominated by an east–west gradient of mean rainfall and variability. The Pacific–South American mode (PSA), El Niño–Southern Oscillation (ENSO), and the southern annular mode (SAM) each show clear influences on the interannual variability of Tasmanian rainfall. Composites of rainfall during each phase of ENSO and the PSA suggest a notable islandwide influence of these climate modes on Tasmanian rainfall. In contrast, the positive phase of the SAM is associated with drier conditions over the west of the island. The PSA and the SAM project most prominently over the southwest of the island, whereas the ENSO signature is strongest in the north. Empirical orthogonal functions (EOFs) of rainfall over Tasmania show a leading mode (explaining 72% of total variance) of coherent islandwide in-phase anomalies with dominant periods of 2 and 5 yr. The second EOF accounts for ∼14% of total variation, characterized by out-of-phase east–west anomalies, which is likely a combination of all three modes. The EOF1 mode can be attributed to ENSO, the PSA, and to a lesser extent the SAM.
Changing Frequency and Intensity of Rainfall Extremes over India from 1951 to 2003
Authors: Krishnamurthy Chandra Kiran B. , Lall Upmanu , Kwon Hyun-Han
Published: March 2009

Using a 1951–2003 gridded daily rainfall dataset for India, the authors assess trends in the intensity and frequency of exceedance of thresholds derived from the 90th and the 99th percentile of daily rainfall. A nonparametric method is used to test for monotonic trends at each location. A field significance test is also applied at the national level to assess whether the individual trends identified could occur by chance in an analysis of the large number of time series analyzed. Statistically significant increasing trends in extremes of rainfall are identified over many parts of India, consistent with the indications from climate change models and the hypothesis that the hydrological cycle will intensify as the planet warms. Specifically, for the exceedance of the 99th percentile of daily rainfall, all locations where a significant increasing trend in frequency of exceedance is identified also exhibit a significant trend in rainfall intensity. However, extreme precipitation frequency over many parts of India also appears to exhibit a decreasing trend, especially for the exceedance of the 90th percentile of daily rainfall. Predominantly increasing trends in the intensity of extreme rainfall are observed for both exceedance thresholds.
The Production and Dissipation of Compensated Thermohaline Variance by Mesoscale Stirring
Authors: Smith K. Shafer , Ferrari Raffaele
Published: March 2009

Temperature–salinity profiles from the region studied in the North Atlantic Tracer Release Experiment (NATRE) show large isopycnal excursions at depths just below the thermocline. It is proposed here that these thermohaline filaments result from the mesoscale stirring of large-scale temperature and salinity gradients by geostrophic turbulence, resulting in a direct cascade of thermohaline variance to small scales. This hypothesis is investigated as follows: Measurements from NATRE are used to generate mean temperature, salinity, and shear profiles. The mean stratification and shear are used as the background state in a high-resolution horizontally homogeneous quasigeostrophic model. The mean state is baroclinically unstable, and the model produces a vigorous eddy field. Temperature and salinity are stirred laterally in each density layer by the geostrophic velocity and vertical advection is by the ageostrophic velocity. The simulated temperature–salinity diagram exhibits fluctuations at depths just below the thermocline of similar magnitude to those found in the NATRE data. It is shown that vertical diffusion is sufficient to absorb the laterally driven cascade of tracer variance through an amplification of filamentary slopes by small-scale shear. These results suggest that there is a strong coupling between vertical mixing and horizontal stirring in the ocean at scales below the deformation radius.
Robustness of an Effective Diffusivity Diagnostic in Oceanic Flows
Authors: Shuckburgh Emily , Jones Helen , Marshall John , Hill Chris
Published: March 2009

The robustness of Nakamura’s effective diffusivity diagnostic for quantifying eddy diffusivities of tracers within a streamwise-average framework is carefully examined in an oceanographic context, and the limits of its applicability are detailed. The near-surface Southern Ocean geostrophic flow, obtained from altimetric observations, is chosen for particular examination since it exhibits strong eddy activity. Careful analysis indicates that the effective diffusivity calculation is not strongly sensitive to the resolution of the velocity field or to the tracer initial conditions (after a spinup time of 3 months), and that a numerical diffusivity of 50 m2 s−1 is appropriate to resolve the Batchelor scale at a computational resolution of . The spatial variability of the effective diffusivity is examined and shown to be related to the eddy kinetic energy (EKE), mean zonal current (u), and phase speed of the eddies (c), following the streamwise averge of EKE/(u − c)2, in agreement with linear baroclinic instability theory. The temporal variability of the effective diffusivity over the period 1996–2001 indicates significant variability on seasonal time scales with a magnitude of ±10%–15%. Interannual variations are investigated and discussed in the context of changes in the wind stress associated with the southern annular mode.
Comparison of Local and Nonlocal Observation Operators for the Assimilation of GPS RO Data with the NCEP GSI System: An OSSE Study
Authors: Ma Zaizhong , Kuo Ying-Hwa , Wang Bin , Wu Wan-Shu , Sokolovskiy Sergey
Published: March 2009

In this study, an Observing System Simulation Experiment (OSSE) is performed to evaluate the performance of a nonlocal excess phase operator and a local refractivity operator for a GPS radio occultation (RO) sounding that passes through the eye of Hurricane Katrina as simulated by a high-resolution model, with significant horizontal refractivity gradients. Both observation operators are tested on the NCEP gridpoint statistical interpolation (GSI) data assimilation system at 12- and 36-km horizontal resolution. It is shown that the shape and magnitude of the analysis increments for sea level pressure, temperature, and water vapor mixing ratio exhibit significant differences between the use of local and nonlocal operators. The nonlocal operator produces more accurate analyses when verified against the “truth” derived from the ground truth run. It is found that the improvements of the analysis with the use of the nonlocal operator over that of the local operator are essentially the same at 12- and 36-km horizontal resolution. An additional experiment is performed over a region with small horizontal gradients. As expected, the use of both nonlocal and local operators produces similar results over such a region.
Why is Spirituality Integral to Management Education? My Experience of Integrating Management and Spirituality
Authors: Narayanswamy Ramnath
Published: March 2009

This article makes a strong case in favour of linking spirituality to management education. The author has used his experiences as a teacher of management studies, as well as the knowledge that he has gathered as a seeker in search of self–revelation to locate the role and signifi cance of spirituality in the managerial context. The analytic–driven search for information and knowledge, the intellect–driven explanations of context and an exposure to lifeskills linked to emotional intelligence are traditional, albeit insuffi cient, inputs to management education. Such an education is incapable of developing well–rounded individuals capable of handling paradoxes, confl icts and something that managers traditionally have very low tolerance for—ambiguity. This necessitates the inclusion of spiritual intelligence described by the author as a search for inner unfoldment, making the transition from self–consciousness to consciousness of the Self. The article draws heavily on the Advaita–Vedanta tradition of Sanatana Dharma to delineate the tools and processes that are integral to the craft of a practicing manager. The act of managing is perceived as a battle where the three armours of analytical, emotional and spiritual intelligence are to be simultaneously deployed by global managers to negotiate the grey and ambiguous waters of global business. It is spiritual intelligence that enables the manager to awaken the fi rm to its true potential, address questions of philosophy (including vision and mission) and awaken the fi rm to its larger role in terms of corporate social responsibility.
Covenons! We Owe Our Store to the Company's Soul...
Authors: Yoos ii Charles J. , Barker James R.
Published: March 2009

We argue that in contemporary business organizations, in which fundamental purpose is construed to be increased value—especially in ‘participative’ organizations, in which non–hierarchal interaction (for example, work teams) is the norm; and in ‘adaptive’ organizations, in which unpredictable change is the rule—a process of values covenanting will be much more valueable than just espoused values or even values covenants. We propose such a process model for organizational values covenanting and argue that such covenanting reflects an anthropomorphism of the human character development process, validated in terms of the theory of viable systems.
Coping at Work
Authors: Sandoff Mette , Widell Gill
Published: March 2009

The intention of this article is to continue the discussion on the tension in the relations between joy and commitment of employees on the one side and type of organization on the other. Earlier empirical studies of disciplinary practices among teachers and warders were developed with the help of hedonism as a psychological concept, attribution theories, theories on motivation and theories on the conflict between the individual and the organization. From these standpoints, a typology on coping strategies in work contexts was developed, where four possible ‘ideal’ roles an individual can take were described. Most studies on disciplining, hedonism, and so, focus on the painful side of coping. Few studies focus on what people do in order to feel well, which is in focus for this article. The frame of reference here is discussed and developed in relation to work places where risks are at stake. The tensions between individual commitment and organizational demands might be most strengthened in such organizations.
Technology of Indian Sea Navigation (c. 1200–c. 1800)
Authors: B. Arunachalam
Published: March 2009

India has a rich and hoary tradition of maritime ventures over millennia. Since the days of the Indus Valley Civilisation, Indian seafarers have voy–aged across the Arabian Sea and the Bay of Bengal and even beyond for trade, religious and cultural objectives. Through experience and inheri–tance over generations, these seamen acquired maritime craft skills and wisdom that formed the bedrock of a total navigational package that stood the test of time and survived till an instrumented modern technology took over.
Agricultural Technology in Early Medieval India (c. A.D. 500–1300)
Authors: Chakravarti Ranabir
Published: March 2009

The article discusses the spread of agriculture to an unprecedented degree in the period from c. A.D. 500 to 1300 (early medieval times) on the basis of both epigraphic and textual materials that also speak of considerable diversity of crops, including what may be considered as cash crops. The author pays attention to the role of metal—especially iron—technology in the development of agriculture during this period. It also argues for betterment in manuring. Inseparably associated with the expansion of agriculture—as an impact of the issuance of profuse number of land grants—are better irrigation technologies. The diversity of irrigation tech-niques and hydraulic projects, local and supra local, had intimate linkages with the variability of access to precious water resources in disparate areas of the subcontinent. In this connection, the article also offers early Indian perceptions of the monsoons; it also seeks to underline the meteor-ologists’ observations of the correlation between the flood-level in the Nile catchment area (by the use of the Nilometer) and the pattern of rainfall in the subcontinent on a long chronological range.
Ischemic Injury to White Matter: An Age-Dependent Process
Authors: Baltan Selva
Published: March 2009

The risk for ischemic stroke increases drastically with age, although reasons for this remain unexplored. White matter (WM) and gray matter constitute equal proportions of the brain, and WM is injured in most strokes. Axonal injury and dysfunction are responsible for much of the disability associated with clinical deficits observed after stroke. The authors recently reported that central nervous system WM is inherently more vulnerable to ischemic injury in older mice, and the mechanisms of WM injury change as a function of age. Ischemic WM injury in older mice is predominately mediated by a Ca2+-independent excitotoxicity involving overactivation of AMPA/kainate receptors. Glutamate release, due to reverse glutamate transport, occurs earlier and is more robust in older mice that show up-regulation of GLT1, the main glutamate transporter. Blockade of NMDA receptors does not improve WM function after ischemia in the young but aggravates ischemic injury in older mice. The main goals of this research update are to summarize the evidence for equivalent brain insults inducing more damage with aging, and to highlight the importance of age in any successful stroke therapy.
Individual Differences in Episodic Memory: The Role of Self-initiated Encoding Strategies
Authors: Kirchhoff Brenda A.
Published: March 2009

Individuals' abilities to form and retrieve episodic memories vary widely. Consistent with this, there are substantial individual differences in brain activity during encoding and retrieval that are associated with individual differences in memory performance. Growing evidence suggests that individual differences in self-initiated encoding strategy use play an important role in individual differences in episodic memory and brain activity during intentional encoding. This review examines the role of individual differences in self-initiated encoding strategy use in individual differences in episodic memory, and outlines the major findings of brain lesion and functional neuroimaging studies that characterize the neural correlates of individual differences in self-initiated encoding strategy use. The relevance of individual differences in self-initiated encoding strategy use to understanding episodic memory impairments and alterations in brain activity in clinical populations such as individuals with schizophrenia is also discussed.
Agrin, Aquaporin-4, and Astrocyte Polarity as an Important Feature of the Blood-Brain Barrier
Authors: Wolburg Hartwig , Noell Susan , Wolburg-Buchholz Karen , Mack Andreas , Fallier-Becker Petra
Published: March 2009

The blood-brain barrier (BBB) does not exclusively refer to brain endothelial cells, which are the site of the barrier proper. In the past few years, it has become increasingly clear that BBB endothelial cells depend considerably on the brain microenvironment to a degree exceeding the environmental influence in other organs. The concept of the BBB has been continuously developed over the decades, culminating now in the recognition that endothelial cell function in the brain is not limited to simply mediating energy and oxygen transfer between blood and neural tissue. Endothelial cells are rather “Janus-headed beings” that are active partners of both luminal molecules and cells, as well as subendothelial cells such as pericytes, astrocytes, and neurons. In this overview, the authors present and discuss both the role of astroglial cells in managing the BBB and aspects of pathological alterations in the brain as far as the BBB is involved. After a brief introduction of the BBB that describes the structure and function of the brain capillary endothelial cells, the authors report on both the water channel protein aquaporin-4 (AQP4) in astrocytes and the extracellular matrix between astrocytes/pericytes and endothelial cells. The AQP4 has an important impact on the homeostasis in the brain parenchyma; however, the mechanistic cascade from the composition of the astrocyte membrane to the maintenance of BBB properties in the endothelial cells, including their tight junction formation, is still completely unknown.
Respiratory Circuits: Function, Mechanisms, Topology, and Pathology
Authors: Mironov Sergej
Published: March 2009

Neuroscientists have long sought to understand how circuits in the nervous system are organized to generate the precise neural outputs that underlie particular behaviors. Recent studies deepened our understanding of the mechanisms responsible for the generation of the rhythmic output for breathing. Here, the author focuses on issues that are pertinent for the respiratory network and considers its organization and how it derives the functional output. The author discusses pacemaker and network mechanisms of rhythm generation, which are now combined into a novel concept of emergent network activity due to coherent excitation of pacemaker groups. He discusses subcellular basis of this hypothesis and possible mechanisms of synchronization within respiratory network. These new findings in respiratory neuroscience are further applied to explain modifications in breathing during hypoxia and possible origins of respiratory disorders that may be acquired during neural development and aging.
Synaptic Plasticity, Neurogenesis, and Functional Recovery after Spinal Cord Injury
Authors: Darian-Smith Corinna
Published: March 2009

Spinal cord injury research has greatly expanded in recent years, but our understanding of the mechanisms that underlie the functional recovery that can occur over the weeks and months following the initial injury, is far from complete. To grasp the scope of the problem, it is important to begin by defining the sensorimotor pathways that might be involved by a spinal injury. This is done in the rodent and nonhuman primate, which are two of the most commonly used animal models in basic and translational spinal injury research. Many of the better known experimentally induced models are then reviewed in terms of the pathways they involve and the reorganization and recovery that have been shown to follow. The better understood neuronal mechanisms mediating such post-injury plasticity, including dendritic spine growth and axonal sprouting, are then examined.
Selective Si–C Bond Cleavage on a Diorganosilicon Porphyrin Complex Bearing Different Axial Ligands
Authors: Ishida Shintaro , Yoshimura Kimio , Matsumoto Hideyuki , Kyushin Soichiro
Published: March 2009

Tetraphenylporphyrinato methylphenylsilicon complex (abbreviated to Si(TPP)MePh) was synthesized and structurally characterized. Although the Si–Ph bond of Si(TPP)MePh is much longer than the Si–Me bond, photolysis and chemical oxidation of Si(TPP)MePh cleaved the Si–Me bond selectively and gave new phenyl-substituted silicon porphyrins. Theoretical studies of a model compound showed that significant σ–π orbital interaction raised the HOMO and is responsible for the silicon–carbon bond cleavage. The instability of phenyl radical to methyl radical caused selective bond cleavage.
One-step Synthesis of LiVPO4F/C Cathode Material with High Performance
Authors: Zhong Shengkui , Wang Jian , Li Yanwei , Liu Letong , Liu Jiequn , Yang Jiangwen
Published: March 2009

LiVPO4F/C cathode material was synthesized by a novel one-step solid-state reaction method using humic acid as both reduction agent and carbon sources. The SEM image showed that the particles merged with each other to form a porous structure. Electrochemical test showed that the initial discharge capacity of LiVPO4F/C powder was 139 mA h g−1 and the capacity was 132 mA h g−1 after 30 cycles.