bluuebunny/crossref_metadata_2025_split huggingface dataset:
‘We are not eating our own food here’: food security and the cash economy in Eastern Uganda
Authors: Whyte M. A. , Kyaddondo D. 
Published: March 2006

AbstractIn this paper we explore changes in agriculture and provisioning in Bunyole County, located in Tororo District on Uganda's eastern border. Since the 1980s parts of the region have experienced a ‘rice boom’ based on the cultivation of paddy rice in irrigated schemes and seasonal swamps. During the same period, the cultivation of cotton, the traditional cash crop, has declined precipitously. Many households in the region are no longer self‐sufficient in food, and food security is a common concern. Drawing both on anthropological field studies in contrasting parts of Bunyole County (1992–3 and 2001–2), as well as long‐term field research in Bunyole that started in 1969, we examine changes in farming systems and land use, in the gender‐based division of labour in family production, and in the interdependence of families and individuals as expressed in social exchange. We trace the increasing importance of trade in food crops of all sorts and in particular the significance for the local rice economy of an emerging year‐round market for agricultural labour. Finally we examine the developing and changing discourse about ‘food’—as a commercial, a nutritional and a symbolic commodity—and the corresponding discourse about ‘money’. We see food security—at household level and in regions—as an outcome of the strategic actions of individuals. However, we also argue that local debates about food security reflect a changing relationship between ‘food’ and ‘money’—a change that involves both social and productive relationships. In eastern Bunyole these changes are expressed in terms of the new rice economy but, we suggest, the changes are more fundamental, and can be seen in many parts of Uganda. Copyright © 2006 John Wiley & Sons, Ltd.
Compatibility Investigations on Polymer‐Fiber‐Reinforced Cements Modified with Polymer Latexes
Authors: Rottstegge Jörg , Han Charles C. , Hergeth Wolf Dieter 
Published: March 2006

AbstractSummary: In construction, polymer fibers are commonly applied beside steel, glass and mineral fibers to improve material's flexibility to shear stress. As in other composite systems, there are compatibility problems present between the fibers and the cement due to the different chemical natures and the different thermal expansion coefficients of the cement and the polymers. Within this study the interactions between two Portland cements and polymer fibers were investigated by SEM and solid‐state NMR spectroscopy. To improve the wetting ability of the polymer fibers by the cement matrix, redispersible latex powders were successfully applied to improve the adhesion between the cement matrix and the fibers. Within this study, several solid‐state nuclear magnetic resonance (NMR) spectroscopy methods, detecting 1H, 13C, 27Al and 29Si nuclei, and scanning electron microscopy (SEM) were applied. Thus, cement pastes, inorganic additives and organic admixtures could be monitored individually.SEM images of the interface between poly(propylene) fibers and Portland cement, hardened and hydrated in the presence of a 2 wt.‐% poly[(vinyl acetate)‐co‐ethylene] latex.magnified imageSEM images of the interface between poly(propylene) fibers and Portland cement, hardened and hydrated in the presence of a 2 wt.‐% poly[(vinyl acetate)‐co‐ethylene] latex.
Mass spectrometry in grape and wine chemistry. Part II: The consumer protection
Authors: Flamini Riccardo , Panighel Annarita 
Published: March 2006

AbstractControls in food industry are fundamental to protect the consumer health. For products of high quality, warranty of origin and identity is required and analytical control is very important to prevent frauds. In this article, the “state of art” of mass spectrometry in enological chemistry as a consumer safety contribute is reported. Gas chromatography‐mass spectrometry (GC/MS) and liquid‐chromatography‐mass spectrometry (LC/MS) methods have been developed to determine pesticides, ethyl carbamate, and compounds from the yeast and bacterial metabolism in wine. The presence of pesticides in wine is mainly linked to the use of dicarboxyimide fungicides on vineyard shortly before the harvest to prevent theBotrytis cinereaattack of grape. Pesticide residues are regulated at maximum residue limits in grape of low ppm levels, but significantly lower levels in wine have to be detected, and mass spectrometry offers effective and sensitive methods. Moreover, mass spectrometry represent an advantageous alternative to the radioactive‐source‐containing electron capture detector commonly used in GC analysis of pesticides. Analysis of ochratoxin A (OTA) in wine by LC/MS and multiple mass spectrometry (MS/MS) permits to confirm the toxin presence without the use of expensive immunoaffinity columns, or time and solvent consuming sample derivatization procedures. Inductively coupled plasma‐mass spectrometry (ICP/MS) is used to control heavy metals contamination in wine, and to verify the wine origin and authenticity. Isotopic ratio‐mass spectrometry (IRMS) is applied to reveal wine watering and sugar additions, and to determine the product origin and traceability. © 2006 Wiley Periodicals, Inc.
Radial nerve repetitive stimulation in myasthenia gravis
Authors: Petretska Adriana , Jarrar Randa , Rubin Devon I. 
Published: March 2006

AbstractThe purpose of this study was to compare the diagnostic yield of repetitive radial nerve stimulation (RNS) while recording from extensor indicis proprius (EIP) to other commonly used muscle–nerve combinations in patients with myasthenia gravis (MG). Radial RNS with recording from EIP was performed in 20 controls and 20 patients with MG. It revealed an abnormal decrement at rest in 35% of patients compared to 11% with ulnar nerve stimulation, 64% with spinal accessory nerve stimulation, and 74% with facial nerve stimulation. Radial‐EIP RNS is a reliable technique in the evaluation of MG and appears more sensitive than ulnar nerve RNS. Muscle Nerve, 2006
Contractual agreements for coordination and vendor‐managed delivery under explicit transportation considerations
Authors: Toptal Ayşegül , Çetinkaya Sıla 
Published: March 2006

AbstractWe consider the coordination problem between a vendor and a buyer operating under generalized replenishment costs that include fixed costs as well as stepwise freight costs. We study the stochastic demand, single‐period setting where the buyer must decide on the order quantity to satisfy random demand for a single item with a short product life cycle. The full order for the cycle is placed before the cycle begins and no additional orders are accepted by the vendor. Due to the nonrecurring nature of the problem, the vendor's replenishment quantity is determined by the buyer's order quantity. Consequently, by using an appropriate pricing schedule to influence the buyer's ordering behavior, there is an opportunity for the vendor to achieve substantial savings from transportation expenses, which are represented in the generalized replenishment cost function.For the problem of interest, we prove that the vendor's expected profit is not increasing in buyer's order quantity. Therefore, unlike the earlier work in the area, it is not necessarily profitable for the vendor to encourage larger order quantities. Using this nontraditional result, we demonstrate that the concept of economies of scale may or may not work by identifying the cases where the vendor can increase his/her profits either by increasing or decreasing the buyer's order quantity. We prove useful properties of the expected profit functions in the centralized and decentralized models of the problem, and we utilize these properties to develop alternative incentive schemes for win–win solutions. Our analysis allows us to quantify the value of coordination and, hence, to identify additional opportunities for the vendor to improve his/her profits by potentially turning a nonprofitable transaction into a profitable one through the use of an appropriate tariff schedule or a vendor‐managed delivery contract. We demonstrate that financial gain associated with these opportunities is truly tangible under a vendor‐managed delivery arrangement that potentially improves the centralized solution.Although we take the viewpoint of supply chain coordination and our goal is to provide insights about the effect of transportation considerations on the channel coordination objective and contractual agreements, the paper also contributes to the literature by analyzing and developing efficient approaches for solving the centralized problem with stepwise freight costs in the single‐period setting. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006
A simple approach for optimum channel reservation for hand‐over calls in cellular systems
Authors: Laith Mohamed , Bakry Saad Haj , Alheraish Abdulmohsen 
Published: March 2006

AbstractIn cellular mobile communication systems, while an active subscriber is moving from one cell to another, the service of his call needs to be handed over to the base station of the new cell. In such a case, cutting the service, due to all channels being busy at the new base station, would be more annoying to subscribers than normal congestion at the first initiation of calls. This paper is concerned with providing a simple approach for choosing the optimum set of channels that need to be reserved for hand‐over calls, while maintaining an acceptable overall system performance. The approach evaluates channel reservation at the cell level, taking into account the offered traffic, that is both the newly initiated original traffic and the hand‐over traffic. The approach produces a simple mathematical solution based on Erlang‐B formula. It uses the concept of ‘Combined Failure Rate’ to evaluate the required reservation. The approach is supported by a simulation study that verifies its validity. Applications of the approach to illustrate its use are also presented. Copyright © 2006 John Wiley & Sons, Ltd.
A tutorial on using genetic algorithms for the design of network topology
Authors: Al‐Bassam Bassam , Alheraish Abdulmohsen , Bakry Saad Haj 
Published: March 2006

AbstractThe design of network topology is an important part of network design, since network topology is directly associated with network operational behavior, capacity, reliability, and cost. This paper is a tutorial paper concerned with illustrating how the optimization capabilities of genetic algorithms can be used to design suitable network topologies considering basic topology problems. Simple genetic algorithms have been developed for the topology problem of mesh networks, considering single node and single link failure tolerance. The algorithms are based on criteria of two important measures: minimizing the length of communication links; and minimizing traffic flow through these links for given traffic loads. The first measure contributes to minimizing the cost of cabling, while the second measure contributes to minimizing the cost of link capacity. The work provides a useful approach and tools to network students and professionals concerned with the topology design of backbone networks. The developed software is made available on the Internet. Copyright © 2006 John Wiley & Sons, Ltd.
Mitochondrial clustering at the vertebrate neuromuscular junction during presynaptic differentiation
Authors: Lee Chi Wai , Peng H. Benjamin 
Published: March 2006

AbstractDuring vertebrate neuromuscular junction (NMJ) development, presynaptic motor axons differentiate into nerve termini enriched in synaptic vesicles (SVs). At the nerve terminal, mitochondria are also concentrated, but how mitochondria become localized at these specialized domains is poorly understood. This process was studied in cultured Xenopus spinal neurons with mitochondrion‐specific probe MitoTracker and SV markers. In nerve‐muscle cocultures, mitochondria were concentrated stably at sites where neurites and muscle cells formed NMJs, and mitochondria coclustered with SVs where neurites were focally stimulated by beads coated with growth factors. Labeling with a mitochondrial membrane potential‐dependent probe JC‐1 revealed that these synaptic mitochondria were with higher membrane potential than the extrasynaptic ones. At early stages of bead‐stimulation, actin‐based protrusions and microtubule fragmentation were observed in neurites at bead contact sites, suggesting the involvement of cytoskeletal dynamics and rearrangement during presynaptic differentiation. Treating the cultures with an actin polymerization blocker, latrunculin A (Ltn A), almost completely abolished the formation of actin‐based protrusions and partially inhibited bead‐induced mitochondrial and SV clustering, whereas the microtubule disrupting agent nocodazole was ineffective in inhibiting the clustering of mitochondria and SVs. Lastly, in contrast to Ltn A, which blocked bead‐induced clustering of both mitochondria and SVs, the ser/thr phosphatase inhibitor okadaic acid inhibited SV clustering but not mitochondrial clustering. These results suggest that at developing NMJs, synaptogenic stimuli induce the clustering of mitochondria together with SVs at presynaptic terminals in an actin cytoskeleton‐dependent manner and involving different intracellular signaling molecules. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Maladaptation to mental stress mitigated by the adaptive immune system via depletion of naturally occurring regulatory CD4+CD25+ cells
Authors: Cohen Hagit , Ziv Yaniv , Cardon Michal , Kaplan Zeev , Matar Michael A. , Gidron Yori , Schwartz Michal , Kipnis Jonathan 
Published: March 2006

AbstractPeripheral cellular immunity was recently shown to play a critical role in brain plasticity and performance. The antigenic specificity of the participating T cells, however, was not investigated, and nor was their relevance to psychological stress. Here we show, using a mouse model, that adaptive immunity mitigates maladaptation to the acute psychological stress known to trigger abnormal behaviors reminiscent of human post‐traumatic stress disorder. Assessment of behavioral adaptation (measured by the acoustic startle response and avoidance behavior) in mice after their exposure to predator odor revealed that maladaptation was several times more prevalent in T cell‐deficient mice than in their wild‐type counterparts. A single population of T cells reactive to central nervous system (CNS)‐associated self‐protein was sufficient to endow immune‐deficient mice with the ability to withstand the psychological stress. Naturally occurring CD4+CD25+ regulatory T cells were found to suppress this endogenous anti‐stress attribute. These findings suggest that T cells specific to abundantly expressed CNS antigens are responsible for brain tissue homeostasis and help the individual to cope with stressful life episodes. They might also point the way to development of immune‐based therapies for mental disorders, based either on up‐regulation of T cells that partially cross‐react with self‐antigens or on weakening of the activity of regulatory T cells. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Long‐term effects of a single exposure to immobilization: A C‐fos mRNA study of the response to the homotypic stressor in the rat brain
Authors: Vallès Astrid , Martí Octavi , Armario Antonio 
Published: March 2006

AbstractA single exposure to a severe emotional stressor such as immobilization in wooden boards (IMO) causes long‐term (days to weeks) peripheral and central desensitization of the hypothalamic‐pituitary‐adrenal (HPA) response to the same (homotypic) stressor. However, the brain areas putatively involved in long‐term desensitization are unknown. In the present experiment, adult male rats were subjected to 2 h of IMO and, 1 or 4 weeks later, exposed again to 1 h IMO together with stress‐naive rats. C‐fos mRNA activation just after IMO and 1 h after the termination of IMO (post‐IMO) were evaluated by in situ hybridization. Whereas in most brain areas c‐fos mRNA induction caused by the last IMO session was similar in stress‐naive (controls) and previously immobilized rats, a few brain areas showed a reduced c‐fos mRNA response: ventral lateral septum (LSv), medial amygdala (MeA), parvocellular region of the paraventricular hypothalamic nucleus (pPVN), and locus coeruleus (LC). In contrast, an enhanced expression was observed in the medial division of the bed nucleus stria terminalis (BSTMv). The present work demonstrates that a previous experience with a stressor can induce changes in c‐fos mRNA expression in different brain areas in response to the homotypic stressor and suggests that LSv, MeA, and BSTMv may be important for providing signals to lower diencephalic (pPVN) and brainstem (LC) nuclei, which results in a lower physiological response to the homotypic stressor. © 2006 Wiley Periodicals, Inc. J Neurobiol, 2006
Proteomic analysis of the binding partners to enteropathogenic Escherichia coli virulence proteins expressed in Saccharomyces cerevisiae
Authors: Hardwidge Philip R. , Donohoe Sam , Aebersold Ruedi , Finlay B. Brett 
Published: March 2006

AbstractEnteropathogenic Escherichia coli (EPEC) is an enteric human pathogen responsible for much worldwide morbidity and mortality. EPEC uses a type III secretion system to inject bacterial proteins into the cytosol of intestinal epithelial cells to cause diarrheal disease. We are interested in determining the host proteins to which EPEC translocator and effector proteins bind during infection. To facilitate protein enrichment, we created fusions between GST and EPEC virulence proteins, and expressed these fusions individually in Saccharomyces cerevisiae. The biology of S. cerevisiae is well understood and often employed as a model eukaryote to study the function of bacterial virulence factors. We isolated the yeast proteins that interact with individual EPEC proteins by affinity purifying against the GST tag. These complexes were subjected to ICAT combined with ESI‐MS/MS. Database searching of sequenced peptides provided a list of proteins that bound specifically to each EPEC virulence protein. The dataset suggests several potential mammalian targets of these proteins that may guide future experimentation.
Organosoluble and colorless fluorinated poly(ether imide)s from 1,2‐bis(3,4‐dicarboxyphenoxy)benzene dianhydride and trifluoromethyl‐substituted aromatic bis(ether amine)s
Authors: Chung Cheng‐Lin , Yang Chin‐Ping , Hsiao Sheng‐Huei 
Published: March 2006

AbstractA series of novel aromatic poly(ether imide)s (PEI) containing ortho‐catenated phenylene rings and pendant trifluoromethyl group have been prepared from 1,2‐bis(3,4‐dicarboxyphenoxy)benzene dianhydride (1) with seven trifluoromethyl‐substituted aromatic bis(ether amine)s (2a‐g) via a conventional two‐stage process that included ring‐opening polyaddition to form the poly(amic acid)s followed by chemical imidization to the polyimides. These PEIs had inherent viscosities in the range of 0.45–1.17 dL/g that corresponded to weight–average and number–average molecular weights (by gel‐permeation chromatography) of 42,000–102,000 and 28,500–67,500, respectively. All the PEIs were readily soluble in many organic solvents and could be solution‐cast into transparent, flexible, and strong films. These films were essentially colorless; they had a very low yellowness index of 4.34–6.55 and an UV–vis absorption cut‐off wavelength at 361–370 nm. The PEIs exhibited moderate‐to‐high glass‐transition temperatures (Tg) in the range of 185–270 °C, softening temperatures (Ts) in the range of 184–275 °C, and 10% weight loss temperatures higher than 466 °C in nitrogen or in air. They also showed low moisture absorptions of 0.49–0.70% and low dielectric constants of 2.78–3.26 (measured at 10 kHz). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3092–3102, 2006
Copolymerization of poly(vinyl alcohol)‐graft‐poly(1,4‐dioxan‐2‐one) with designed molecular structure by a solid‐state polymerization method
Authors: Chen Si‐Chong , Wang Xiu‐Li , Yang Ke‐Ke , Wu Gang , Wang Yu‐Zhong 
Published: March 2006

AbstractPoly(vinyl alcohol)‐graft‐poly(1,4‐dioxan‐2‐one) (PVA‐g‐PPDO) with designed molecular structure was synthesized by a solid‐state polymerization. The solid‐state copolymerization was preceded by a graft copolymerization of PDO initiated with PVA as a multifunctional initiator, and Sn (Oct)2 as a coininitiator/catalyst in a homogeneous molten state. The polymerization temperature was then decreased and the copolymerization was carried out in a solid state. The products prepared by solid‐state polymerization were characterized by 1H NMR and DSC, and were compared with those synthesized in the homogeneous molten state. The degree of polymerization (Dp), degree of substitution (Ds), yield and the average molecular weight of the graft copolymer with different molecular structure were calculated from the 1H NMR spectra. The results show that the crystallization process during the solid‐state polymerization may suppress the undesirable inter‐ or intramolecular side reactions, then resulting in a controlled molecular structure of PVA‐g‐PPDO. The results of DSC measurement show that the molecular structures determine the thermal behavior of the PVA‐g‐PPDO. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3083–3091, 2006
MO‐LCAO approach and ab initio computations
Authors: Re Giuseppe Del , Capobianco Amedeo 
Published: March 2006

AbstractThe physical reliability and foundations of the Hund–Hückel MO‐LCAO model, in which a molecular orbital (MO) is represented as a linear combination of atomic orbitals (LCAO), are examined in light of ab initio self‐consistent field (SCF) computations with bases of various sizes. It is shown that appropriate linear transformations of the basis make evident a substructure of the relevant ab initio matrices and vectors that justifies the physical assumptions on which the MO‐LCAO model rests. The main conceptual aspects, viz. hydrogen‐like atomic orbitals, hybrids, localized orbitals, give a coherent picture, and the numerical data show that the contributions to occupied orbital energies ignored in the MO‐LCAO model are actually small enough to justify their neglect in chemical structure studies. The numerical parameter values can therefore be read quantitatively in the ab inito results and the importance of the approximations made estimated. These conclusions have been drawn from studies on a variety of molecules with first‐ and second‐row atoms. The well‐established transferability of group properties in molecules suggests that they are generally valid. The claim that hybrids are method‐independent, and therefore features of chemical reality at the orbital level, is discussed due to its relevance for comparisons of the stability of chemical bonds based on overlap. Of course, further work on questions such as electronegativities and promotion is needed. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006