bluuebunny/crossref_metadata_2025 huggingface dataset:
High Sodium Intake Enhances Insulin‐stimulated Glucose Uptake in Rat Epididymal Adipose Tissue
Authors: Fonseca‐Alaniz Miriam H. , Takada Julie , Andreotti Sandra , De Campos Tarcila B.F. , Campaña Amanda B. , Borges‐Silva Cristina N. , Lima Fabio B.
Published: March 2008

Objective: This study investigated the effect of different sodium content diets on rat adipose tissue carbohydrate metabolism and insulin sensitivity.

Methods and Procedures: Male Wistar rats were fed on normal‐ (0.5% Na+; NS), high‐ (3.12% Na+; HS), or low‐sodium (0.06% Na+; LS) diets for 3, 6, and 9 weeks after weaning. Blood pressure (BP) was measured using a computerized tail‐cuff system. An intravenous insulin tolerance test (ivITT) was performed in fasted animals. At the end of each period, rats were killed and blood samples were collected for glucose and insulin determinations. The white adipose tissue (WAT) from abdominal and inguinal subcutaneous (SC) and periepididymal (PE) depots were weighed and processed for adipocyte isolation and measurement of in vitro rates of insulin‐stimulated 2‐deoxy‐d‐[3H]‐glucose uptake (2DGU) and conversion of ‐[U‐14C]‐glucose into 14CO2.

Results: After 6 weeks, HS diet significantly increased the BP, SC and PE WAT masses, PE adipocyte size, and plasma insulin concentration. The sodium dietary content did not influence the whole‐body insulin sensitivity. A higher half‐maximal effective insulin concentration (EC50) from the dose‐response curve of 2DGU and an increase in the insulin‐stimulated glucose oxidation rate were observed in the isolated PE adipocytes from HS rats.

Discussion: The chronic salt overload enhanced the adipocyte insulin sensitivity for glucose uptake and the insulin‐induced glucose metabolization, contributing to promote adipocyte hypertrophy and increase the mass of several adipose depots, particularly the PE fat pad.
Association Between Family Divorce and Children's BMI and Meal Patterns: The GENDAI Study
Authors: Yannakoulia Mary , Papanikolaou Katerina , Hatzopoulou Ioanna , Efstathiou Eleftheria , Papoutsakis Constantina , Dedoussis George V.
Published: March 2008

The aim of this work was to explore the associations between family factors, including divorce, and children's overweight as well as eating and physical activity patterns in a population‐based sample of healthy school‐aged children. In this cross‐sectional study, 1,138 children (53% girls; age: 11.2 ± 0.7 years) from elementary schools in the Attica region participated. Their parents provided sociodemographic information, including their marital status. Overweight status classification was based on weight and height measurements and BMI evaluation. Children completed a physical activity checklist and a questionnaire on meal patterns and eating behaviors. The Eating Style score was calculated: the higher the score, the more frequent a child was engaged in less‐structured feeding practices promoting food intake for reasons other than hunger. Analysis revealed significant association between family divorce and children's overweight: compared with children of married parents, those of divorced had significantly higher BMI levels (20.0 ± 3.6 kg/m2 vs. 21.3 ± 3.4 kg/m2, respectively, P = 0.007). Controlling for socioeconomic and physical activity factors, divorce remains a significant predictor of a higher BMI, along with older age, higher father's and mother's BMI, less children in the family, and more minutes of daily screen time. Children who had experienced a divorce in their family also reported higher Eating Style score, even after adjusting for potential confounders. In conclusion, in this sample of fifth and sixth graders, unfavorable family circumstances have been associated with children's overweight, as well as with aspects of their eating behavior, namely eating style in relation to conditions around food consumption and hunger, independent of other socioeconomic factors.
Association of Postpartum Depression With Weight Retention 1 Year After Childbirth
Authors: Herring Sharon J. , Rich‐Edwards Janet W. , Oken Emily , Rifas‐Shiman Sheryl L. , Kleinman Ken P. , Gillman Matthew W.
Published: March 2008

Objective: To examine the extent to which early postpartum depression is associated with weight retention 1 year after childbirth.

Methods and Procedures: In a prospective cohort study of 850 women enrolled in Project Viva, mothers reported depressive symptoms on the Edinburgh Postnatal Depression Scale (EPDS) at midpregnancy and 6 months postpartum. A score >12 indicated probable depression. We assessed associations of antenatal and postpartum depression with risk of substantial weight retention (at least 5 kg) 1 year after childbirth.

Results: Seven‐hundred thirty‐six women (87%) were not depressed during or after pregnancy, 55 (6%) experienced antenatal depression only, 22 (3%) experienced both antenatal and postpartum depression, and 37 (4%) experienced postpartum depression only. At 1 year, participants retained a mean of 0.6 kg (range −16.4 to 25.5), and 12% retained at least 5 kg. In multivariate logistic regression analyses, after adjustment for weight‐related covariates, maternal sociodemographics, and parity, new‐onset postpartum depression was associated with more than a doubling of risk of retaining at least 5 kg (odds ratio (OR): 2.54, 95% confidence interval (CI): 1.06, 6.09). Antenatal depression, either alone or in combination with postpartum depression, was not associated with substantial weight retention.

Discussion: New‐onset postpartum depression was associated with substantial weight retention in the first postpartum year. Interventions to manage depressive symptoms may help reduce excess weight retained postpartum and aid in the prevention of obesity among women.
Nonlocal branches of cycles, bistability, and topologically persistent mixed mode oscillations
Authors: Bouse E. , Krasnosel’skii A. , Pokrovskii A. , Rachinskii D.
Published: March 2008

A possible mechanism for generating mixed mode oscillations is based on an appropriate S-shaped structure, which graphs the relation between the parameter and the collection of periodic oscillations existing for a particular parameter value in the product of parameter and phase spaces. This natural scenario should be supplemented by simple and constructive criteria of existence, and methods of localization, of such S-shaped structures. These criteria are the main focus of the paper.
Noise-induced mixed-mode oscillations in a relaxation oscillator near the onset of a limit cycle
Authors: Muratov Cyrill B. , Vanden-Eijnden Eric
Published: March 2008

A detailed asymptotic study of the effect of small Gaussian white noise on a relaxation oscillator undergoing a supercritical Hopf bifurcation is presented. The analysis reveals an intricate stochastic bifurcation leading to several kinds of noise-driven mixed-mode oscillations at different levels of amplitude of the noise. In the limit of strong time-scale separation, five different scaling regimes for the noise amplitude are identified. As the noise amplitude is decreased, the dynamics of the system goes from the limit cycle due to self-induced stochastic resonance to the coherence resonance limit cycle, then to bursting relaxation oscillations, followed by rare clusters of several relaxation cycles (spikes), and finally to small-amplitude oscillations (or stable fixed point) with sporadic single spikes. These scenarios are corroborated by numerical simulations.
Multimode dynamics in a network with resource mediated coupling
Authors: Postnov D. E. , Sosnovtseva O. V. , Scherbakov P. , Mosekilde E.
Published: March 2008

The purpose of this paper is to study the special forms of multimode dynamics that one can observe in systems with resource-mediated coupling, i.e., systems of self-sustained oscillators in which the coupling takes place via the distribution of primary resources that controls the oscillatory state of the individual unit. With this coupling, a spatially inhomogenous state with mixed high and low-amplitude oscillations in the individual units can arise. To examine generic phenomena associated with this type of interaction we consider a chain of resistively coupled electronic oscillators connected to a common power supply. The two-oscillator system displays antiphase synchronization, and it is interesting to note that two-mode oscillations continue to exist outside of the parameter range in which oscillations occur for the individual unit. At low coupling strengths, the multi-oscillator system shows high dimensional quasiperiodicity with little tendency for synchronization. At higher coupling strengths, one typically observes spatial clustering involving a few oscillating units. We describe three different scenarios according to which the cluster can slide along the chain as the bias voltage changes.
Ab initio quantum mechanical/molecular mechanical simulation of electron transfer process: Fractional electron approach
Authors: Zeng Xiancheng , Hu Hao , Hu Xiangqian , Cohen Aron J. , Yang Weitao
Published: March 2008

Electron transfer (ET) reactions are one of the most important processes in chemistry and biology. Because of the quantum nature of the processes and the complicated roles of the solvent, theoretical study of ET processes is challenging. To simulate ET processes at the electronic level, we have developed an efficient density functional theory (DFT) quantum mechanical (QM)/molecular mechanical (MM) approach that uses the fractional number of electrons as the order parameter to calculate the redox free energy of ET reactions in solution. We applied this method to study the ET reactions of the aqueous metal complexes Fe(H2O)62+/3+ and Ru(H2O)62+/3+. The calculated oxidation potentials, 5.82 eV for Fe(II/III) and 5.14 eV for Ru(II/III), agree well with the experimental data, 5.50 and 4.96 eV, for iron and ruthenium, respectively. Furthermore, we have constructed the diabatic free energy surfaces from histogram analysis based on the molecular dynamics trajectories. The resulting reorganization energy and the diabatic activation energy also show good agreement with experimental data. Our calculations show that using the fractional number of electrons (FNE) as the order parameter in the thermodynamic integration process leads to efficient sampling and validate the ab initio QM/MM approach in the calculation of redox free energies.
Identification of parameters of dynamic Preisach model by neural networks
Authors: Trapanese Marco
Published: March 2008

In this paper, an approach that allows to identify the parameters of dynamic Preisach model is presented. The fundamental idea of this method is to identify the parameters of a material by using a neural network trained by a collection of hysteresis curves, whose Preisach model is known. After a brief description of dynamic Preisach Model, the neural network that has been used is introduced. The construction of the training data set is illustrated. Finally, the effectiveness of the method is tested on both numerical as well as experimental data.
Hiatus perturbation for a singular Schrödinger operator with an interaction supported by a curve in R3
Authors: Exner P. , Kondej S.
Published: March 2008

We consider Schrödinger operators in L2(R3) with a singular interaction supported by a finite curve Γ. We present a proper definition of the operators and study their properties, in particular, we show that the discrete spectrum can be empty if Γ is short enough. If it is not the case, we investigate properties of the eigenvalues in the situation when the curve has a hiatus of length 2ϵ. We derive an asymptotic expansion with the leading term which a multiple of ϵlnϵ.
Effect of charge distribution on the translocation of an inhomogeneously charged polymer through a nanopore
Authors: Mohan Aruna , Kolomeisky Anatoly B. , Pasquali Matteo
Published: March 2008

We investigate the voltage-driven translocation of an inhomogeneously charged polymer through a nanopore by utilizing discrete and continuous stochastic models. As a simplified illustration of the effect of charge distribution on translocation, we consider the translocation of a polymer with a single charged site in the presence and absence of interactions between the charge and the pore. We find that the position of the charge that minimizes the translocation time in the absence of pore-polymer interactions is determined by the entropic cost of translocation, with the optimum charge position being at the midpoint of the chain for a rodlike polymer and close to the leading chain end for an ideal chain. The presence of attractive and repulsive pore-charge interactions yields a shift in the optimum charge position toward the trailing end and the leading end of the chain, respectively. Moreover, our results show that strong attractive or repulsive interactions between the charge and the pore lengthen the translocation time relative to translocation through an inert pore. We generalize our results to accommodate the presence of multiple charged sites on the polymer. Our results provide insight into the effect of charge inhomogeneity on protein translocation through biological membranes.
An ultrahigh vacuum complementary metal oxide silicon compatible nonlithographic system to fabricate nanoparticle-based devices
Authors: Banerjee Arghya , Das Biswajit
Published: March 2008

Nanoparticles of metals and semiconductors are promising for the implementation of a variety of photonic and electronic devices with superior performances and new functionalities. However, their successful implementation has been limited due to the lack of appropriate fabrication processes that are suitable for volume manufacturing. The current techniques for the fabrication of nanoparticles either are solution based, thus requiring complex surface passivation, or have severe constraints over the choice of particle size and material. We have developed an ultrahigh vacuum system for the implementation of a complex nanosystem that is flexible and compatible with the silicon integrated circuit process, thus making it suitable for volume manufacturing. The system also allows the fabrication of Ohmic contacts and isolation dielectrics in an integrated manner, which is a requirement for most electronic and photonic devices. We have demonstrated the power and the flexibility of this new system for the manufacturing of nanoscale devices by implementing a variety of structures incorporating nanoparticles. Descriptions of this new fabrication system together with experimental results are presented in this article. The system explains the method of size-selected deposition of nanoparticles of any metallic, semiconducting, and (or) insulating materials on any substrate, which is very important in fabricating useful nanoparticle-based devices. It has also been shown that at elevated substrate temperature, a selective deposition of the nanoparticles is observed near the grain-boundary regions. However, in these natural systems, there will always be low and favorable energy states present away from the grain-boundary regions, leading to the undesirable deposition of nanoparticles in the far-grain-boundary regions, too.
Electrical properties of metal-oxide-semiconductor structures with low-energy Ge-implanted and annealed thin gate oxides
Authors: Kapetanakis E. , Normand P. , Holliger P.
Published: March 2008

The electrical characteristics of low-energy (3keV) Ge-implanted and, subsequently, thermal annealed SiO2 layers are investigated through capacitance-voltage (C-V) and conductance-voltage (G-V) measurements of metal-oxide-semiconductor capacitors. Particular emphasis is placed on the properties of such gate oxides for memory applications. Capacitance measurements at flatband voltage before and after the application of constant voltage stress in the accumulation regime indicate that the charge trapping behavior of the devices undergoes a major change after annealing at temperatures higher than 910°C. The latter change is identified as a relocation of Ge atoms mainly toward the upper portion of the oxide with a significant fraction of them leaving the oxide; a finding in harmony with secondary ion mass spectroscopy analysis. The interface trap density (Dit) for the thin (9–12nm) implanted oxides decreases with increasing annealing temperature, approaching at 950°C the Dit levels in the mid-1010eV−1cm−2 range of the nonimplanted samples. At elevated annealing temperatures (>1000°C), the device C-V characteristics are substantially disturbed. In this case, the presence of electrically active Ge atoms at an extended depth in the substrate modifies the intrinsic electrical properties of the n-Si substrate, lending a p-type conductivity character to the device high-frequency C-V curves. Substrate electrical modification is interpreted through a model that takes into account the formation of a SiO2∕Ge-rich-Si∕n-Si system. The SiO2∕Ge-rich-Si interface presents very low Dit levels as revealed by conductance loss characteristics. The present study suggests that a combination of Ge implantation into SiO2 films and thermal annealing may be exploited in damage-free SiGe epitaxial growth technology based on Ge implantation.
A new approach for efficient simulation of Coulomb interactions in ionic fluids
Authors: Denesyuk Natalia A. , Weeks John D.
Published: March 2008

We propose a simplified version of local molecular field (LMF) theory to treat Coulomb interactions in simulations of ionic fluids. LMF theory relies on splitting the Coulomb potential into a short-ranged part that combines with other short-ranged core interactions and is simulated explicitly. The averaged effects of the remaining long-ranged part are taken into account through a self-consistently determined effective external field. The theory contains an adjustable length parameter σ that specifies the cutoff distance for the short-ranged interaction. This can be chosen to minimize the errors resulting from the mean-field treatment of the complementary long-ranged part. Here we suggest that in many cases an accurate approximation to the effective field can be obtained directly from the equilibrium charge density given by the Debye theory of screening, thus eliminating the need for a self-consistent treatment. In the limit σ→0, this assumption reduces to the classical Debye approximation. We examine the numerical performance of this approximation for a simple model of a symmetric ionic mixture. Our results for thermodynamic and structural properties of uniform ionic mixtures agree well with similar results of Ewald simulations of the full ionic system. In addition, we have used the simplified theory in a grand-canonical simulation of a nonuniform ionic mixture where an ion has been fixed at the origin. Simulations using short-ranged truncations of the Coulomb interactions alone do not satisfy the exact condition of complete screening of the fixed ion, but this condition is recovered when the effective field is taken into account. We argue that this simplified approach can also be used in the simulations of more complex nonuniform systems.
Local symmetry change in BaF2:Mn2+ at ∼50K: Microscopic insight
Authors: Garcia-Fernandez P. , Aramburu J. A. , Barriuso M. T. , Moreno M.
Published: March 2008

The microscopic origin of the abrupt cubic-tetrahedral symmetry change associated with the local a2u vibrational mode observed by electron paramagnetic resonance in BaF2:Mn2+ at ∼50K is explored by means of density functional theory calculations. It is found that while the a2u vibrational frequencies calculated for MnF86− in CaF2 (168cm−1) and SrF2 (132cm−1) are real, in the case of BaF2:Mn2+, the adiabatic potential curve along this mode exhibits a double well with a small barrier of 50cm−1. Although the ground and first excited vibrational states are localized around the energy minima, the rest of the excited states resemble those of a harmonic oscillator centered at Q(a2u)=0. Moreover, only the inclusion of the anharmonic coupling between a2u and t1u modes allows one to understand the Td-Oh transition temperature. It is shown that both the unusually high Mn2+–F− distance in BaF2:Mn2+ and the pseudo-Jahn–Teller interaction of the t2g(xy;xz;yz) antibonding orbital with filled t1u orbitals favor the a2u instability. The calculated a2u force constant for different electronic states supports this conclusion.
Dynamical systems and nilpotent sub-Riemannian geometry
Authors: Anzaldo-Meneses A. , Monroy-Pérez F.
Published: March 2008

We consider dynamical systems determined by distributions of real analytic vector fields, the equations of motion, and the associated gauge transformation are presented in detail. A gradation of the associated Lie algebras leads to the consideration of polynomial vector fields. The minimization of kinetic energy action in the class of horizontal curves associated with the distribution is formulated as a sub-Riemannian geodesic problem. Normal geodesics are fully described for the so-called Gaveau–Brockett distribution. The exponential mapping, the unitary spheres, and the wave fronts are calculated for particular cases.
Drift-diffusion crossover and the intrinsic spin diffusion lengths in semiconductors
Authors: Miah M. Idrish
Published: March 2008

We study the propagation of electron spin density polarization and spin currents in n-doped semiconductors within the two-component drift-diffusion model in an applied electric field (E). The drift and diffusion contributions to the spin currents are examined, which shows how the spin current could be enhanced. We find that there is a crossover field (Ex), where the drift and diffusion contribute equally to the spin current in the downstream direction. This suggests a possible way to identify whether the process for a given E would be in the drift or diffusion regime. We derive the expression for Ex and show that the intrinsic spin diffusion length in a semiconductor can be calculated directly from Ex. The results will be useful in obtaining transport properties of the carriers’ spin in semiconductors. This investigation, however, highlights the need for further experiments to be conducted to measure Ex in semiconductors.
Time resolved measurements of spin and carrier dynamics in InAs films
Authors: Kini R. N. , Nontapot K. , Khodaparast G. A. , Welser R. E. , Guido L. J.
Published: March 2008

We report time resolved measurements of spin and carrier relaxation in InAs films with carrier densities of 1.3×1016 and 1.6×1016cm−3 grown on (001) and (111) GaAs, respectively. We used standard pump-probe and magneto-optical Kerr effect spectroscopy at different excitation wavelengths, power densities, and temperatures. We observed sensitivity of carrier and spin relaxation time to the photoinduced carrier density but not to the variation in temperature. We explain our results using the Elliot–Yafet picture of spin relaxation process in narrow gap semiconductors.
Balanced homodyning for apertureless near-field optical imaging
Authors: Labardi M. , Tikhomirov O. , Ascoli C. , Allegrini M.
Published: March 2008

A quadrature optical detection technique, based on polarized balanced-homodyne interferometry, has been developed for specific application to apertureless near-field scanning optical microscopy (ANSOM). With such technique, multiplicative background interference, inficiating quantitative optical imaging in standard homodyne-based ANSOM, can be suppressed. Periodic modulation of interferometric optical phase, typically employed in heterodyne-based ANSOMs even to such purpose, is not needed in the present configuration. Homodyne detection also facilitates detection of harmonic components of the ANSOM optical signal at the probe/sample distance modulation frequency, necessary for near-field discrimination and suppression of artifacts. Furthermore, since amplitude signal is not affected by phase fluctuations generated in the optical path of the interferometer, an optical fiber could be included in one interferometer arm, to couple the ANSOM head to the detection system, obtaining improved versatility of the instrument. A demonstration of the interferometer performance is given by a test confocal optical scan of a mirror surface. This technique, as applied to near-field microscopy, is anticipated to provide absolute values of optical contrast not depending on background interference and topography artifacts.
Comparative passivation effects of self-assembled mono- and multilayers on GaAs junction field effect transistors
Authors: Lee Kangho , Lu Gang , Facchetti Antonio , Janes David B. , Marks Tobin J.
Published: March 2008

Control of semiconductor interface state density with molecular passivation is essential for developing conduction-based biosensors. In this study, GaAs junction field effect transistors (JFETs) are fabricated and characterized before and after passivation of the GaAs surface with self-assembled mono- and multilayers. The JFETs functionalized with 1-octadecanethiol monolayers and two types of self-assembled organic nanodielectric (SAND) multilayers exhibit significantly different threshold voltage (Vth) and subthreshold slope (Ssub) characteristics versus the unpassivated devices and provide useful information on the quality of the passivation. Two-dimensional device simulations quantify the effective density of fixed surface charges and interfacial traps and argue for the importance of the type-III SAND ionic charges in enhancing GaAs JFET response characteristics.
Ag
∕
Pb
Te
(
111
)
interface behavior studied by photoemission spectroscopy
Authors: Wu H. F. , Zhang H. J. , Lu Y. H. , Si J. X. , Li H. Y. , Bao S. N. , Wu H. Z. , He P.
Published: March 2008

We performed investigations on the formation of Ag∕PbTe(111) interface by using photoemission spectroscopy. Upon initial Ag deposition, both Pb 4f and Te 3d core levels and the valence-band edge showed shifts to high binding energy, from which the band bending at Ag∕PbTe(111) is determined to be 0.13eV. Upon further Ag deposition, new components appear in Pb and Te core levels, with intensities remaining constant even at higher Ag thickness. The experimental results, together with ab initio calculation, indicate that both Te and Pb outdiffuse to the outmost surface, and a single Te-terminated Pb–Te bilayer is formed over Ag film on PbTe(111).
Low current resistive switching in Cu–SiO2 cells
Authors: Schindler C. , Weides M. , Kozicki M. N. , Waser R.
Published: March 2008

Resistive switching in Ir∕SiO2∕Cu memory cells was investigated. The proposed switching mechanism is the formation and dissolution of a Cu filament. Under positive bias, Cu cations migrate through SiO2 and are reduced at the counterelectrode forming a filament. The filament is dissolved under reverse bias. The write current can be reduced down to 10pA which is four orders of magnitude below published values and shows the potential of extremely low power-consuming memory cells. Furthermore, a comparison of the charge flow in the high resistance state and the energy for writing is given for write currents between 25pA and 10nA.
Effect of metal contacts on the electrical characteristics of Al2O3 dielectric thin films
Authors: Yip G. , Qiu J. , Ng W. T. , Lu Z. H.
Published: March 2008

The effect of top metal electrodes on the electrical characteristics of Al2O3 metal-insulator-metal capacitors is studied. The leakage current and breakdown characteristics were observed to have a strong dependence on the electrode material. Devices with Al electrodes exhibited significantly higher breakdown voltages compared to devices with Au, Ni, Cu, and Ag electrodes. Introducing an Al diffusion barrier dramatically increased the breakdown field and reduced the leakage current for capacitors with Ag, Au, and Cu electrodes. The electrical characteristics were found to relate well to material properties of the contacting metals, such as ionization potential and diffusion coefficient.
Flexible large area ferroelectret sensors for location sensitive touchpads
Authors: Buchberger Gerda , Schwödiauer Reinhard , Bauer Siegfried
Published: March 2008

Cellular polypropylene ferroelectrets are flexible transducer materials with dominant longitudinal piezoelectricity. They can be used for transient pressure sensing applications, due to the low cost of the sensor material. The authors show that ferroelectrets allow for the production of keyboards and touch pads with a customizable layout. Large area resistive electrodes on the ferroelectret with electronics at the edges avoid the preparation of complex sensor matrices. A touch pad of 10×10cm2 area was tested by applying a force of 1.7N on an area with a diameter of 5mm in a grid matrix with 23×23 elements.
Plant adaptation to fluctuating environment and biomass production are strongly dependent on guard cell potassium channels
Authors: Lebaudy Anne , Vavasseur Alain , Hosy Eric , Dreyer Ingo , Leonhardt Nathalie , Thibaud Jean-Baptiste , Véry Anne-Aliénor , Simonneau Thierry , Sentenac Hervé
Published: March 2008

At least four genes encoding plasma membrane inward K
+
channels (K
in
channels) are expressed in
Arabidopsis
guard cells. A double mutant plant was engineered by disruption of a major K
in
channel gene and expression of a dominant negative channel construct. Using the patch-clamp technique revealed that this mutant was totally deprived of guard cell K
in
channel (GCK
in
) activity, providing a model to investigate the roles of this activity in the plant. GCK
in
activity was found to be an essential effector of stomatal opening triggered by membrane hyperpolarization and thereby of blue light-induced stomatal opening at dawn. It improved stomatal reactivity to external or internal signals (light, CO
2
availability, and evaporative demand). It protected stomatal function against detrimental effects of Na
+
when plants were grown in the presence of physiological concentrations of this cation, probably by enabling guard cells to selectively and rapidly take up K
+
instead of Na
+
during stomatal opening, thereby preventing deleterious effects of Na
+
on stomatal closure. It was also shown to be a key component of the mechanisms that underlie the circadian rhythm of stomatal opening, which is known to gate stomatal responses to extracellular and intracellular signals. Finally, in a meteorological scenario with higher light intensity during the first hours of the photophase, GCK
in
activity was found to allow a strong increase (35%) in plant biomass production. Thus, a large diversity of approaches indicates that GCK
in
activity plays pleiotropic roles that crucially contribute to plant adaptation to fluctuating and stressing natural environments.
A new phase of solid iodine with different molecular covalent bonds
Authors: Zeng Qifeng , He Zhi , San Xiaojiao , Ma Yanming , Tian Fubo , Cui Tian , Liu Bingbing , Zou Guangtian , Mao Ho-kwang
Published: March 2008

There is a great interest in the behavior of diatomic molecular solids under extremely high-pressure conditions that lead to pressure-induced metallization, molecular dissociation, and formation of atomic phase. The consensus has been that the phase-transition sequence that happened in both solid bromine and iodine is from a molecular phase (phase I), to an incommensurate phase (phase V), and then to an atomic phase (phase II), with increasing pressure. However, a puzzle remains unresolved for both solids: pressure-induced X and Y bands were observed in the Raman spectra in the molecular phase at low pressures, even before the onset of phase V. Here, we suggest a phase for solid iodine in such a low-pressure range (designated as phase I′) in which two different covalent intramolecular bonds coexist, based on first-principles calculations and later corroborated by x-ray diffraction experiments. The pressure dependence of the X and Y bands and other vibrational frequencies measured experimentally can be explained nicely by combining the vibrational modes of phase I and phase I′. These results help improve our understanding on the pressure-induced molecular dissociation and metallization in diatomic solids and may shed some light on the investigation of similar phenomena in solid H
2
.
Meiotic Spindle Pole Bodies Acquire the Ability to Assemble the Spore Plasma Membrane by Sequential Recruitment of Sporulation-specific Components in Fission Yeast
Authors: Nakase Yukiko , Nakamura-Kubo Michiko , Ye Yanfang , Hirata Aiko , Shimoda Chikashi , Nakamura Taro
Published: March 2008

The spindle pole body (SPB) of Schizosaccharomyces pombe is required for assembly of the forespore membrane (FSM) during meiosis. Before de novo biogenesis of the FSM, the meiotic SPB forms outer plaques, an event referred to as SPB modification. A constitutive SPB component, Spo15, plays an indispensable role in SPB modification and sporulation. Here, we analyzed two sporulation-specific genes, spo13+and spo2+, which are not required for progression of meiotic nuclear divisions, but are essential for sporulation. Spo13 is a 16-kDa coiled-coil protein, and Spo2 is a 15-kDa nonconserved protein. Both Spo13 and Spo2 specifically associated with the meiotic SPB. The respective deletion mutants are viable, but defective in SPB modification and in the onset of FSM formation. Spo13 and Spo2 localized on the cytoplasmic side of the SPB in close contact with the nascent FSM. Localization of Spo13 to the SPB was dependent on Spo15 and Spo2; that of Spo2 depended only on Spo15, suggesting that their recruitment to the SPB is strictly controlled. Spo2 physically associated with both Spo15 and Spo13, but Spo13 and Spo15 did not interact directly. Taken together, these observations indicate that Spo2 is recruited to the SPB during meiosis and then assists in the localization of Spo13 to the outer surface of the SPB.
External Liberalization, Economic Performance, and Social Policy
Authors: Berg Janine , Taylor Lance
Published: March 2008

Economic policy in developing and postsocialist economies during the last ten to fifteen years of the 20th century had one dominating theme: wave of external deregulation showing up as packages aimed at liberalizing the balance of payments on both current and capital accounts, along with large but highly volatile foreign capital movements. This chapter draws together recent historical evidence from nine developing and transition economies (Argentina, Colombia, Cuba, India, South Korea, Mexico, Russia, Turkey, and Zimbabwe) to study and assess these changes and their economic and social consequences, summarizing the findings from several perspectives, with findings from Latin America brought in where they add information. It begins with a review of different ways of analyzing liberalization and globalization, and then the basic approach of the country papers and their key results on growth and inequality are presented. These points are elaborated in the form of a simple macroeconomic model that captures the flavor of liberalization on the ground, and an initial application of the model is followed by a review of decomposition exercises for effective demand, employment, productivity growth, and functional income distribution from the country papers; the results of the decompositions and other salient indicators of the effects of liberalization are displayed in a set of tables, which are used to construct country vignettes. Next comes a discussion of the social policy issues emphasized by the country authors, and the chapter closes with a review of open questions regarding macroeconomic and external policy alternatives, and whether social policy can ameliorate the worst effects of globalization and balance of payments deregulation.
Argentina: Balance‐Of‐Payments Liberalization: Effects on Growth, Employment and Income
Authors: Frenkel Roberto , González Rozada Martín
Published: March 2008

This chapter gives a summary analysis of the growth process, the performance of the labor market, and the evolution of income and wages in the context generated by the market‐friendly structural reforms of the early 1990s in Argentina, which targeted the privatization of a large proportion of state‐owned enterprises, as well as trade and financial openings; the stabilization policies that were applied in the 1990s are also discussed. There are seven sections to the chapter: the first presents some aspects of the macroeconomic dynamics, mainly in the form of graphs that facilitate the comparison between the 1980s and 1990s; the second presents an econometric model that describes the macroeconomic performance in the 1990s and summarizes the estimation results; the third focuses on the behavior of the urban labor market at the national level and in Greater Buenos Aires (GBA); the fourth includes the formulation and estimation of an econometric model of the aggregate urban labor market; the fifth uses GBA data to analyze variations in urban employment by sector of activity and sociodemographic characteristics; the sixth studies the performance of production, employment, and productivity in the manufacturing sector using data from the industrial survey, and an econometric model of labor demand in this sector is presented – the econometric estimations, together with the trade information on the manufacturing sector, are utilized to separate and calculate the different effects on the employment contraction in this sector. The last section focuses on income and its distribution.
Cuba: External Opening, Labor Market and Inequality of Labor Incomes
Authors: Ferriol Muruaga Angela
Published: March 2008

The external opening that took place in the Cuban economy in the 1990s has unique characteristics that differentiate it from the experience of other countries: the Cuban opening was accompanied by a severe external adjustment of magnitude, much greater than that experienced by other economies of the region, and this opening was also part of a wider process of modification of the economic model, since there was a transformation from a highly centralized system based on balancing the distribution of material resources, to a system based mainly on financial mechanisms and a greater degree of managerial autonomy. So, Cuba's external opening has had a strong impact on all social and economic structures, and has become an important stimulating factor in helping to reinsert the Cuban economy into the international economy. This chapter gives an exposition of the main characteristics of the economic reforms, with emphasis on the external opening, changes in the labor market, and social policy measures. Subsequently, three aspects are analyzed (macroeconomic performance; mesoeconomic dynamics; and changes in the labor market, including workers’ remuneration); all those cases that reflect a direct relationship between the opening of the economy and labor revenues obtained by the population are also examined. Lastly, an analysis is made of the relationship between the labor revenues of households and their economic situation.
India: Globalization and Its Social Discontents
Authors: Dutt Amitava Krishna , Rao J. Mohan
Published: March 2008

This chapter examines the historical record with a view of assessing the diverse views about India's economic reforms, which have aimed to liberalize and globalize its economy. First, the content of reforms undertaken are briefly examined and then an account is given of how the effects of globalization are to be explored in the following sections. The third section looks at some macroeconomic dimensions of performance, including the realized effects of openness on external transactions, on economic growth, and on trends in the rural sector, which remains the mainstay of employment. The fourth section summarizes trends in employment and unemployment, and the changing commodity composition of employment and its distribution across the formal/informal divide. The fifth section delves into some controversies surrounding the assessment of changes in income distribution and poverty under the impact of reforms, and the sixth turns to the government policy toward social safety nets.
Conclusion: Looking Back, Looking Ahead
Authors: Silvia Paul J.
Published: March 2008

Given the large body of research, psychology's curiosity in interest is clearly flourishing. This concluding chapter reviews the major themes in the psychology of interest and suggests productive directions for future research. Some themes include the functional value of interest in learning and motivation, the usefulness of emotion theories for understanding what interest is and how it works, and the emerging role of cognitive processes in explaining the origins of stable interests. For future research, psychologists should bring together the diverse bodies of work on interest. Suggestions for research are given for intersecting research on emotion, learning, reading, personality, aesthetics, vocational interests, and the development of interests.
Molecular Approaches in Crustacean Evolutionary Ecology
Authors: Neigel Joseph , Mahon Brian
Published: March 2008

Molecular markers provide powerful means to analyze relationships of descent both among individuals and among taxa. Microsatellite loci have become the standard for studies of paternity and kinship (allowing analysis of mating systems) because they are highly polymorphic and codominant. Phylogenetic comparative methods are intended to separate instances of convergent or parallel evolution from shared evolutionary history by analyzing the phylogenetic distributions of traits. They have been criticized for the assumptions they make about how traits evolve, although not all of these methods make the same assumptions. Most assume that an accurate phylogeny is known. However, crustacean phylogenies have mostly been based on small numbers of sequences that do not have the most desirable properties for phylogenetic inference. This situation is likely to be remedied by the ongoing development of PCR primers that amplify additional independently segregating nuclear loci.
Agonistic Behavior in Freshwater Crayfish
Authors: Moore Paul A.
Published: March 2008

Fighting success and dominance in crayfish depends on a variety of extrinsic and intrinsic factors. Most intrinsic factors studied to date are related to the physical size of the crayfish. Larger crayfish or those with larger chelae often have advantages in agonistic interactions. Age, sex, and reproductive status can influence the physical size of the carapace and major chelae. These and other factors (e.g., social history) may also influence the intrinsic neurochemistry of individuals. Extrinsic factors that lead to increased dominance include the availability of resources, signal transmission properties, and status pheromones in the environment. Presently, it is largely unknown how these factors interact together to produce dominance. From an ultimate perspective, the evolutionary consequence of aggression and dominance is assumed to be tied to reproductive success or increased resource holding potential. This chapter uses a multidisciplinary and multilevel approach to address the question “what makes a crayfish dominant?”
Mating Strategies in Isopods
Authors: Jormalainen Veijo
Published: March 2008

Isopods show a wide range in mating systems. Mate guarding by males before copulation occurs commonly in most free-living taxa, with the notable exception of the terrestrial Oniscidea. Such guarding prior to copulation is interpreted as a male mate monopolization strategy, evolved as a response to short female receptivity to copulation. Males are able to assess female maturity and to adjust guarding duration accordingly; relatively long guarding duration is often optimal for males. Guarding has no known benefits for females. Moreover, guarding is likely to impose costs for females, thus leading to a sexual conflict. Experimental studies suggest that conflicts over the start of guarding generate sexual selection for traits related to obtaining or resisting mates, as well as for traits related to cryptic female choice. Isopod mating systems can be used to clarify the roles played by traditional female choice and intersexual conflicts in sexual selection.
Sperm Demand and Allocation in Decapod Crustaceans
Authors: Sainte-Marie Bernard
Published: March 2008

This chapter examines trends in male gametic strategies in relation to female sperm demand among gonochoristic decapod crustaceans. Female lifetime fecundity and number of eggs per spawn can vary much more among decapod species than in other taxa in which gametic strategies have been explored. Female anatomy and life history determine a gradient of complexity and potential duration for sperm storage, lasting from a few hours to several years. The spermathecae of some decapods have enormous capacity and filling may be antagonistic to ovary development. Sperm requirements associated with high female fecundity can be met by large sperm investments from individual males, promiscuity, and/or very effective use of sperm. As in many other taxa, male decapods may allocate sperm strategically as a function of female size (fecundity) and mated status, number of mating opportunities, and risk and intensity of sexual (sperm) competition.
Behavioral Ecology of Semiterrestrial Crayfish
Authors: Richardson Alastair M.M.
Published: March 2008

Like a number of the other crustaceans, burrowing crayfish live in a situation that tends to lead to prolonged associations between mother and offspring, and even overlapping generations in some species. Under these situations, social behaviors are likely to evolve, but at this stage the only ones that have been identified among burrowing crayfish are between mother and offspring, in terms of defense and grooming. Burrowing was a pre-adaptation that has allowed crayfish to move out of open waters onto land, but it has also imposed severe restrictions on their movements and dispersal. The development of social behaviors may compensate for these restrictions to some extent. Present knowledge on the behavioral ecology of semi-terrestrial crayfish is scarce, but initial observations suggest that future studies on the reproductive biology of burrowing crayfish may improve our understanding of social evolution in crustaceans.
Anthropogenic Stressors and Their Effects on the Behavior of Aquatic Crustaceans
Authors: van Son Thijs Christiaan , Thiel Martin
Published: March 2008

Four categories of anthropogenic stressors affect the behavior and vital functions of crustaceans in aquatic ecosystems: pollution, introduction of non-indigenous species, stock manipulation, and habitat destruction. The most affected vital functions are, in descending order of importance, reproduction, nutrition and growth, and habitat selection. Two principal groups of stressors were distinguished: (i) pollution and species introduction, for which most of the effects on crustacean behavior were observed directly; and (ii) fishing and habitat destruction, for which most of the evidence was circumstantial. In many cases, pollution and species introduction affect individuals directly, whereas fishing and habitat destruction affect crustacean behaviors indirectly, primarily by changes in important population (e.g., sex ratio and population density) or ecosystem (e.g., habitat, physico-chemical, species dominance, species composition) parameters. The information yielded by this review and that of future studies may prove useful in designing efficient conservation plans.
Last Rights
Authors: Branch Ben S. , Ray Hugh M. , Russell Robin
Published: March 2008

This book examines the business liquidation process — the winding up of the affairs of a company that has either decided voluntarily to liquidate or been forced to liquidate by its creditors. The contributors to the book have substantial hands-on experience in the reorganization and liquidation of businesses, the sale of business assets, and management of commercial litigation. They share their approach to maximizing and creating value in the deteriorating and chaotic business environment that so often leads to a company going out of business. The legal forums for liquidation — bankruptcy, state receivership, federal receivership, and assignment for the benefit of creditors — are explained. The liquidator's role, powers, duties, oversight, and compensation are outlined and the special rules for bankruptcy trustees are set forth. The chapters also cover the major tasks of liquidation including investigation of the company, termination of employees, disposition of assets, evaluation of litigation, resolution of claim, distributions and ultimately, and the dissolution or “winding down” of the company.