bluuebunny/crossref_metadata_2025 huggingface dataset:
Mouse Models for Efficacy Testing of Agents against Radiation Carcinogenesis — A Literature Review
Authors: Rivina Leena , Schiestl Robert
Published: December 2012

As the number of cancer survivors treated with radiation as a part of their therapy regimen is constantly increasing, so is concern about radiation-induced cancers. This increases the need for therapeutic and mitigating agents against secondary neoplasias. Development and efficacy testing of these agents requires not only extensive in vitro assessment, but also a set of reliable animal models of radiation-induced carcinogenesis. The laboratory mouse (Mus musculus) remains one of the best animal model systems for cancer research due to its molecular and physiological similarities to man, small size, ease of breeding in captivity and a fully sequenced genome. This work reviews relevant M. musculus inbred and F1 hybrid animal models and methodologies of induction of radiation-induced leukemia, thymic lymphoma, breast, and lung cancer in these models. Where available, the associated molecular pathologies are also included.
Assessing the Influence of Land Use and Land Cover Datasets with Different Points in Time and Levels of Detail on Watershed Modeling in the North River Watershed, China
Authors: Huang Jinliang , Zhou Pei , Zhou Zengrong , Huang Yaling
Published: December 2012

Land use and land cover (LULC) information is an important component influencing watershed modeling with regards to hydrology and water quality in the river basin. In this study, the sensitivity of the Soil and Water Assessment Tool (SWAT) model to LULC datasets with three points in time and three levels of detail was assessed in a coastal subtropical watershed located in Southeast China. The results showed good agreement between observed and simulated values for both monthly and daily streamflow and monthly NH4+-N and TP loads. Three LULC datasets in 2002, 2007 and 2010 had relatively little influence on simulated monthly and daily streamflow, whereas they exhibited greater effects on simulated monthly NH4+-N and TP loads. When using the two LULC datasets in 2007 and 2010 compared with that in 2002, the relative differences in predicted monthly NH4+-N and TP loads were −11.0 to −7.8% and −4.8 to −9.0%, respectively. There were no significant differences in simulated monthly and daily streamflow when using the three LULC datasets with ten, five and three categories. When using LULC datasets from ten categories compared to five and three categories, the relative differences in predicted monthly NH4+-N and TP loads were −6.6 to −6.5% and −13.3 to −7.3%, respectively. Overall, the sensitivity of the SWAT model to LULC datasets with different points in time and levels of detail was lower in monthly and daily streamflow simulation than in monthly NH4+-N and TP loads prediction. This research provided helpful insights into the influence of LULC datasets on watershed modeling.
Assessing the Impact of Socioeconomic Variables on Small Area Variations in Suicide Outcomes in England
Authors: Congdon Peter
Published: December 2012

Ecological studies of suicide and self-harm have established the importance of area variables (e.g., deprivation, social fragmentation) in explaining variations in suicide risk. However, there are likely to be unobserved influences on risk, typically spatially clustered, which can be modeled as random effects. Regression impacts may be biased if no account is taken of spatially structured influences on risk. Furthermore a default assumption of linear effects of area variables may also misstate or understate their impact. This paper considers variations in suicide outcomes for small areas across England, and investigates the impact on them of area socio-economic variables, while also investigating potential nonlinearity in their impact and allowing for spatially clustered unobserved factors. The outcomes are self-harm hospitalisations and suicide mortality over 6,781 Middle Level Super Output Areas.
Chemical Constituents from Andrographis echioides and Their Anti-Inflammatory Activity
Authors: Shen De-Yang , Juang Shin-Hun , Kuo Ping-Chung , Huang Guan-Jhong , Chan Yu-Yi , Damu Amooru , Wu Tian-Shung
Published: December 2012

Phytochemical investigation of the whole plants of Andrographis echioides afforded two new 2'-oxygenated flavonoids (1) and (2), two new phenyl glycosides (3) and (4), along with 37 known structures. The structures of new compounds were elucidated by spectral analysis and chemical transformation studies. Among the isolated compounds, (1–2) and (6–19) were subjected into the examination for their iNOS inhibitory bioactivity. The structure-activity relationships of the flavonoids for their inhibition of NO production were also discussed.
Isolation and Characterization of Nine Microsatellite Loci for a Parasitoid Wasp, Encarsia smithi (Silvestri) (Hymenoptera: Aphelinidae)
Authors: Uesugi Ryuji , Sato Yasushi
Published: December 2012

The parasitoid wasp Encarsia smithi is an important agent in the classical biological control of two species of invasive spiny whiteflies, Aleurocanthus spiniferus and Aleurocanthus camelliae. To evaluate the performance of parasitism indexed by genetic diversity, a highly polymorphic genetic marker is required. In this report, nine microsatellite loci are described for E. smithi. The microsatellite loci were obtained through the construction of an enriched library and exhibited polymorphisms (2–6 alleles per locus) and high levels of expected heterozygosities (0.203–0.780, average 0.537). Linkage disequilibrium and null alleles were not detected in these microsatellite loci. The isolated microsatellite markers may be useful to estimate the genetic diversity of E. smithi.
Ultraviolet B (UVB) Irradiation-Induced Apoptosis in Various Cell Lineages in Vitro
Authors: Salucci Sara , Burattini Sabrina , Battistelli Michela , Baldassarri Valentina , Maltarello Maria , Falcieri Elisabetta
Published: December 2012

Ultraviolet B (UVB) radiation acts as a strong apoptotic trigger in many cell types, in tumor and normal cells. Several studies have demonstrated that UVB-induced cell death occurs through the generation of reactive oxygen species. The consequent oxidative stress includes the impairment of cellular antioxidants, the induction of DNA damage and the occurrence of apoptosis. In this review, we investigated UVB apoptotic action in various cell models by using ultrastructural, molecular and cytofluorimetric techniques. Myeloid leukemia HL-60, T-lymphoblastoid Molt-4 and myelomonocytic U937 human cells, generally affected by apoptotic stimuli, were studied. Human chondrocytes and C2C12 skeletal muscle cells, known to be more resistant to damage, were also considered. All of them, when exposed to UVB radiation, revealed a number of characteristic apoptotic markers. Membrane blebbing, cytoplasm shrinkage and chromatin condensation were detected by means of electron microscopy. DNA cleavage, investigated by using agarose gel electrophoresis and TUNEL reaction, was observed in suspended cells. Differently, in chondrocytes and in skeletal muscle cells, oligonucleosomic DNA fragmentation did not appear, even if a certain TUNEL positivity was detected. These findings demonstrate that UVB radiation appears to be an ideal tool to study the apoptotic behavior.
Why Flavins Are not Competitors of Chlorophyll in the Evolution of Biological Converters of Solar Energy
Authors: Kritsky Mikhail , Telegina Taisiya , Vechtomova Yulia , Buglak Andrey
Published: December 2012

Excited flavin molecules can photocatalyze reactions, leading to the accumulation of free energy in the products, and the data accumulated through biochemical experiments and by modeling prebiological processes suggest that flavins were available in the earliest stages of evolution. Furthermore, model experiments have shown that abiogenic flavin conjugated with a polyamino acid matrix, a pigment that photocatalyzes the phosphorylation of ADP to form ATP, could have been present in the prebiotic environment. Indeed, excited flavin molecules play key roles in many photoenzymes and regulatory photoreceptors, and the substantial structural differences between photoreceptor families indicate that evolution has repeatedly used flavins as chromophores for photoreceptor proteins. Some of these photoreceptors are equipped with a light-harvesting antenna, which transfers excitation energy to chemically reactive flavins in the reaction center. The sum of the available data suggests that evolution could have led to the formation of a flavin-based biological converter to convert light energy into energy in the form of ATP.
Pavilion Lake Microbialites: Morphological, Molecular and Biochemical Evidence for a Cold-Water Transition to Colonial Aggregates
Authors: Schulze-Makuch Dirk , Lim Darlene , Laval Bernard , Turse Carol , António Marina , Chan Olivia , Pointing Stephen , Brady Allyson , Reid Donnie , Irwin Louis
Published: December 2012

The presence of microbialite structures in a freshwater, dimictic mid-latitudelake and their establishment after the last ice age about 10,000 years ago is puzzling.Freshwater calcite microbialites at Pavilion Lake, British Columbia, Canada, consist of acomplex community of microorganisms that collectively form large, ordered structuredaggregates. This distinctive assemblage of freshwater calcite microbialites was studied through standard microbial methods, morphological observations, phospholipid fatty acid(PLFA) analysis, DNA sequencing and the identification of quorum sensing molecules.Our results suggest that the microbialites may represent a transitional form from theexclusively prokaryotic colonial precursors of stromatolites to the multicellular organismicaggregates that give rise to coral reefs.
Hydrazine-Assisted Formation of Indium Phosphide (InP)-Based Nanowires and Core-Shell Composites
Authors: Patzke Greta , Kontic Roman , Shiolashvili Zeinab , Makhatadze Nino , Jishiashvili David
Published: December 2012

Indium phosphide nanowires (InP NWs) are accessible at 440 °C from a novel vapor phase deposition approach from crystalline InP sources in hydrazine atmospheres containing 3 mol % H2O. Uniform zinc blende (ZB) InP NWs with diameters around 20 nm and lengths up to several tens of micrometers are preferably deposited on Si substrates. InP particle sizes further increase with the deposition temperature. The straightforward protocol was extended on the one-step formation of new core-shell InP–Ga NWs from mixed InP/Ga source materials. Composite nanocables with diameters below 20 nm and shells of amorphous gallium oxide are obtained at low deposition temperatures around 350 °C. Furthermore, InP/Zn sources afford InP NWs with amorphous Zn/P/O-coatings at slightly higher temperatures (400 °C) from analogous setups. At 450 °C, the smooth outer layer of InP-Zn NWs is transformed into bead-shaped coatings. The novel combinations of the key semiconductor InP with isotropic insulator shell materials open up interesting application perspectives in nanoelectronics.
4862F, a New Inhibitor of HIV-1 Protease, from the Culture of Streptomyces I03A-04862
Authors: Liu Xiao , Gan Maoluo , Dong Biao , Zhang Tian , Li Yongzhen , Zhang Yuqin , Fan Xiuyong , Wu Yexiang , Bai Shuoke , Chen Minghua , Yu Liyan , Tao Peizhen , Jiang Wei , Si Shuyi
Published: December 2012

We have isolated an extraordinary pentapeptide, called 4862F, from the culture broth of Streptomyces albosporus I03A-04862 by Diaion HP-20 macroporous adsorbent resin column, ODS-A and Sephadex LH-20 chromatography, followed by preparative HPLC. This peptide shows inhibitory activity against HIV-1 protease. The structure was elucidated by spectroscopic approaches, including ESI-MS and various NMR methods. Absolute configuration of the amino acid residues in 4862F was defined using Marfey’s method, and the structure was identified as N,N,N-(trimethylated)-Tyr-L-Leu-L-Val-L-Leu-(dehydrated)-His. The peptide 4862F displays inhibitory activity against HIV-1 protease, with IC50 values of 15.26 nM, using a fluorescence-based assay.
Proteomic and Functional Analyses Reveal MAPK1 Regulates Milk Protein Synthesis
Authors: Lu Li-Min , Li Qing-Zhang , Huang Jian-Guo , Gao Xue-Jun
Published: December 2012

L-Lysine (L-Lys) is an essential amino acid that plays fundamental roles in protein synthesis. Many nuclear phosphorylated proteins such as Stat5 and mTOR regulate milk protein synthesis. However, the details of milk protein synthesis control at the transcript and translational levels are not well known. In this current study, a two-dimensional gel electrophoresis (2-DE)/MS-based proteomic technology was used to identify phosphoproteins responsible for milk protein synthesis in dairy cow mammary epithelial cells (DCMECs). The effect of L-Lys on DCMECs was analyzed by CASY technology and reversed phase high performance liquid chromatography (RP-HPLC). The results showed that cell proliferation ability and β-casein expression were enhanced in DCMECs treated with L-Lys. By phosphoproteomics analysis, six proteins, including MAPK1, were identified up-expressed in DCMECs treated with 1.2 mM L-Lys for 24 h, and were verified by quantitative real-time PCR (qRT-PCR) and western blot. Overexpression and siRNA inhibition of MAPK1 experiments showed that MAPK1 upregulated milk protein synthesis through Stat5 and mTOR pathway. These findings that MAPK1 involves in regulation of milk synthesis shed new insights for understanding the mechanisms of milk protein synthesis.
Molecular Mechanism Underlying Anti-Inflammatory and Anti-Allergic Activities of Phytochemicals: An Update
Authors: Bellik Yuva , Boukraâ Laïd , Alzahrani Hasan , Bakhotmah Balkees , Abdellah Fatiha , Hammoudi Si , Iguer-Ouada Mokrane
Published: December 2012

The resort worldwide to edible medicinal plants for medical care has increased significantly during the last few years. Currently, there is a renewed interest in the search for new phytochemicals that could be developed as useful anti-inflammatory and anti-allergic agents to reduce the risk of many diseases. The activation of nuclear transcription factor-kappa B (NF-κB) has now been linked to a variety of inflammatory diseases, while data from numerous studies underline the importance of phytochemicals in inhibiting the pathway that activates this transcription factor. Moreover, the incidence of type I allergic disorders has been increasing worldwide, particularly, the hypersensitivity to food. Thus, a good number of plant products with anti-inflammatory and anti-allergic activity have been documented, but very few of these compounds have reached clinical use and there is scant scientific evidence that could explain their mode of action. Therefore, this paper intends to review the most salient recent reports on the anti-inflammatory and anti-allergic properties of phytochemicals and the molecular mechanisms underlying these properties.
Harnessing Sun’s Energy with Quantum Dots Based Next Generation Solar Cell
Authors: Halim Mohammad
Published: December 2012

Our energy consumption relies heavily on the three components of fossil fuels (oil, natural gas and coal) and nearly 83% of our current energy is consumed from those sources. The use of fossil fuels, however, has been viewed as a major environmental threat because of their substantial contribution to greenhouse gases which are responsible for increasing the global average temperature. Last four decades, scientists have been searching for alternative sources of energy which need to be environmentally clean, efficient, cost-effective, renewable, and sustainable. One of the promising sustainable sources of energy can be achieved by harnessing sun energy through silicon wafer, organic polymer, inorganic dye, and quantum dots based solar cells. Among them, quantum dots have an exceptional property in that they can excite multiple electrons using only one photon. These dots can easily be synthesized, processed in solution, and incorporated into solar cell application. Interestingly, the quantum dots solar cells can exceed the Shockley-Queisser limit; however, it is a great challenge for other solar cell materials to exceed the limit. Theoretically, the quantum dots solar cell can boost the power conversion efficiency up to 66% and even higher to 80%. Moreover, in changing the size of the quantum dots one can utilize the Sun’s broad spectrum of visible and infrared ranges. This review briefly overviews the present performance of different materials-based solar cells including silicon wafer, dye-sensitized, and organic solar cells. In addition, recent advances of the quantum dots based solar cells which utilize cadmium sulfide/selenide, lead sulfide/selenide, and new carbon dots as light harvesting materials has been reviewed. A future outlook is sketched as to how one could improve the efficiency up to 10% from the current highest efficiency of 6.6%.
Dietary Habits, Nutrients and Bone Mass in Spanish Premenopausal Women: The Contribution of Fish to Better Bone Health
Authors: Calderon-Garcia Julian , Moran Jose , Roncero-Martin Raul , Rey-Sanchez Purificacion , Rodriguez-Velasco Francisco , Pedrera-Zamorano Juan
Published: December 2012

The moderate consumption of fish is recommended for a healthy diet and is also a feature of the Mediterranean diet. Fish is a major food group in diets throughout the world, and studies show that fish consumption is associated with a lower risk of a number of conditions. Spain has one of the highest annual per capita consumptions of fish worldwide. As fish is a source of high quality protein; n-3 polyunsaturated fatty acids; vitamins, such as A and D; and minerals, such as selenium, calcium, iodine, magnesium, copper and zinc, nutrients that have positive effects on bone characteristics, it has been proposed that its consumption could improve bone health. In this cross-sectional study, we have investigated the relationship between dietary habits and nutrient intake of 151 Spanish premenopausal women and analyzed the association of fish consumption on bone mass measured by quantitative ultrasound of the phalanges. A higher (P < 0.05) bone mass and vitamin D intake (P < 0.05) was observed in the group with a fish intake of 5–7 servings/week. We conclude that increased fish consumption is helpful in maintaining an adequate bone mass in Spanish premenopausal women.
Strategies To Modulate Heritable Epigenetic Defects in Cellular Machinery: Lessons from Nature
Authors: Pandian Ganesh , Sugiyama Hiroshi
Published: December 2012

Natural epigenetic processes precisely orchestrate the intricate gene network by expressing and suppressing genes at the right place and time, thereby playing an essential role in maintaining the cellular homeostasis. Environment-mediated alteration of this natural epigenomic pattern causes abnormal cell behavior and shifts the cell from the normal to a diseased state, leading to certain cancers and neurodegenerative disorders. Unlike heritable diseases that are caused by the irreversible mutations in DNA, epigenetic errors can be reversed. Inheritance of epigenetic memory is also a major concern in the clinical translation of the Nobel Prize-winning discovery of induced pluripotent stem cell technology. Consequently, there is an increasing interest in the development of novel epigenetic switch-based therapeutic strategies that could potentially restore the heritable changes in epigenetically inherited disorders. Here we give a comprehensive overview of epigenetic inheritance and suggest the prospects of therapeutic gene modulation using epigenetic-based drugs, in particular histone deacetylase inhibitors. This review suggests that there is a need to develop therapeutic strategies that effectively mimic the natural environment and include the ways to modulate the gene expression at both the genetic and epigenetic levels. The development of tailor-made small molecules that could epigenetically alter DNA in a sequence-specific manner is a promising approach for restoring defects in an altered epigenome and may offer a sustainable solution to some unresolved clinical issues.
Pharmacokinetic Evaluation of a DSPE-PEG2000 Micellar Formulation of Ridaforolimus in Rat
Authors: Remsberg Connie , Zhao Yunqi , Takemoto Jody , Bertram Rebecca , Davies Neal , Forrest Marcus
Published: December 2012

The rapamycin analog, ridaforolimus, has demonstrated potent anti-proliferative effects in cancer treatment, and it currently is being evaluated in a range of clinical cancer studies. Ridaforolimus is an extremely lipophilic compound with limited aqueous solubility, which may benefit from formulation with polymeric micelles. Herein, we report the encapsulation of ridaforolimus in 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-methoxy-poly(ethylene glycol 2000) (DSPE-PEG2000) via a solvent extraction technique. Micelle loading greatly improved the solubility of ridaforolimus by approximately 40 times from 200 μg/mL to 8.9 mg/mL. The diameters of the drug-loaded micelles were 33 ± 15 nm indicating they are of appropriate size to accumulate within the tumor site via the enhanced permeability and retention (EPR) effect. The DSPE-PEG2000 micelle formulation was dosed intravenously to rats at 10 mg/kg and compared to a control of ridaforolimus in ethanol/PEG 400. The micelle significantly increased the half-life of ridaforolimus by 170% and decreased the clearance by 58%, which is consistent with improved retention of the drug in the plasma by the micelle formulation.
Seeding and Harvest: A Framework for Unsupervised Feature Selection Problems
Authors: Chen Gang , Cai Yuanli , Shi Juan
Published: December 2012

Feature selection, also known as attribute selection, is the technique of selecting a subset of relevant features for building robust object models. It is becoming more and more important for large-scale sensors applications with AI capabilities. The core idea of this paper is derived from a straightforward and intuitive principle saying that, if a feature subset (pattern) has more representativeness, it should be more self-organized, and as a result it should be more insensitive to artificially seeded noise points. In the light of this heuristic finding, we established the whole set of theoretical principles, based on which we proposed a two-stage framework to evaluate the relative importance of feature subsets, called seeding and harvest (S&H for short). At the first stage, we inject a number of artificial noise points into the original dataset; then at the second stage, we resort to an outlier detector to identify them under various feature patterns. The more precisely the seeded points can be extracted under a particular feature pattern, the more valuable and important the corresponding feature pattern should be. Besides, we compared our method with several state-of-the-art feature selection methods on a number of real-life datasets. The experiment results significantly confirm that our method can accomplish feature reduction tasks with high accuracy as well as low computing complexity.
Adaptive Optics Technology for High-Resolution Retinal Imaging
Authors: Lombardo Marco , Serrao Sebastiano , Devaney Nicholas , Parravano Mariacristina , Lombardo Giuseppe
Published: December 2012

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effects of optical aberrations. The direct visualization of the photoreceptor cells, capillaries and nerve fiber bundles represents the major benefit of adding AO to retinal imaging. Adaptive optics is opening a new frontier for clinical research in ophthalmology, providing new information on the early pathological changes of the retinal microstructures in various retinal diseases. We have reviewed AO technology for retinal imaging, providing information on the core components of an AO retinal camera. The most commonly used wavefront sensing and correcting elements are discussed. Furthermore, we discuss current applications of AO imaging to a population of healthy adults and to the most frequent causes of blindness, including diabetic retinopathy, age-related macular degeneration and glaucoma. We conclude our work with a discussion on future clinical prospects for AO retinal imaging.
Sovereignty without Mastery
Authors: McLane Patrick
Published: December 2012

In The Beast and the Sovereign v.1, Derrida argues that classical sovereignty is linked to the performative act of declaring oneself master. Thus, each sovereign asserts a distinction between the masterful self and the mastered other. Derrida contends that the sovereign distinction between self and other maps onto a distinction between sovereign autonomy and a mechanical determination said to characterize others of all kinds. This gives rise to a differentiated binary between responsibility, capacity and restraint on the one side against reaction, instinct and danger on the other, which, Derrida suggests, operates across traditional separations, such as man/animal, man/machine, mind/body and, of course, sovereign and beast. This paper argues that Derrida’s reading of Paul Celan and Georges Bataille may be understood as a pursuit of an alternative sovereignty. This alternative sovereignty would be without mastery and its binaries. I suggest that Derrida finds such an alternative sovereignty in the “majesty” of poetry, which, in his own poetic gesture, allows him to upset traditional distinctions.
Of Plants, and Other Secrets
Authors: Marder Michael
Published: December 2012

In this article, I inquire into the reasons for the all-too-frequent association of plants and secrets. Among various hypotheses explaining this connection from the standpoint of plant morphology and physiology, the one that stands out is the idea that plants are not only objects in the natural environment, but also subjects with a peculiar mode of accessing the world. The core of the “plant enigma” is, therefore, onto-phenomenological. Positively understood, the secret of their subjectivity leaves just enough space for the self-expression and the self-interpretation of vegetal life.
2050 Scenarios for Long-Haul Tourism in the Evolving Global Climate Change Regime
Authors: Vorster Shaun , Ungerer Marius , Volschenk Jako
Published: December 2012

Tourism and its “midwife”, aviation, are transnational sectors exposed to global uncertainties. This scenario-building exercise considers a specific subset of these uncertainties, namely the impact of the evolving global climate change regime on long-haul tourism (LHT), with a 2050 horizon. The basic problematique is that unconstrained growth in aviation emissions will not be compatible with 2050 climate stabilisation goals, and that the stringency and timing of public policy interventions could have far-reaching impacts — either on the market for future growth of LHT, or the natural ecosystem on which tourism depends. Following an intuitive-logic approach to scenario-building, three meta-level scenarios that can be regarded as “possible” futures for the evolution of LHT are described. Two of these, i.e., the “grim reaper” and the “fallen angel” scenarios, are undesirable. The “green lantern” scenario represents the desired future. Long-haul tourist destinations should heed the early warning signals identified in the scenario narratives, and contribute towards realising the desired future. They should further guard against being passive victims if the feared scenarios materialise, by adapting, repositioning early upon reading the signposts, hedging against risks, and seizing new opportunities.
Climate and Food Production: Understanding Vulnerability from Past Trends in Africa’s Sudan-Sahel
Authors: Yengoh Genesis
Published: December 2012

Just how influential is rainfall on agricultural production in the Sudan-Sahel of Africa? And, is there evidence that support for small-scale farming can reduce the vulnerability of crop yields to rainfall in these sensitive agro-ecological zones? These questions are explored based on a case study from Cameroon’s Sudan-Sahel region. Climate data for 20 years and crop production data for six major food crops for the same years are used to find patterns of correlation over this time period. Results show a distinction of three periods of climatic influence of agriculture: one period before 1989, another between 1990 and 1999 and the last from 2000 to 2004. The analysis reveals that, while important in setting the enabling biophysical environment for food crop cultivation, the influence of rainfall in agriculture can be diluted by proactive policies that support food production. Proactive policies also reduce the impact of agriculturally relevant climatic shocks, such as droughts on food crop yields over the time-series. These findings emphasize the extent of vulnerability of food crop production to rainfall variations among small-holder farmers in these agro-ecological zones and reinforce the call for the proactive engagement of relevant institutions and support services in assisting the efforts of small-scale food producers in Africa’s Sudan-Sahel. The implications of climate variability on agriculture are discussed within the context of food security with particular reference to Africa’s Sudan-Sahel.
Differences in Susceptibility to Okadaic Acid, a Diarrhetic Shellfish Poisoning Toxin, between Male and Female Mice
Authors: Suzuki Hodaka
Published: December 2012

The mouse bioassay (MBA) for diarrhetic shellfish poisoning (DSP) toxins has been widely used in many countries of the world. In the Japanese and EU methods, male mice are designated to be used for MBA. Female mice were described to be less susceptible than male mice. To the best of our knowledge, however, there have been no reports on the details of sex differences in susceptibility to DSP toxins. In this study, we investigated whether, and to what extent, female mice are less sensitive to DSP toxins. A lethal dose of okadaic acid (OA), one of the representative DSP toxins, was injected intraperitoneally into mice. The mice were observed until 24 hours after injection. Both male and female mice of ICR and ddY strains, which are designated in the Japanese official method, were compared. All the mice were four weeks old and weighed 18–20 g. The experiments were repeated twice. The lethality was 70%–100%. Survival analysis showed no sex differences in susceptibility to OA, but ICR female mice showed significant resistance compared with other groups in one out of two trials. These results indicate that sex differences were not clear but, nonetheless, male mice showed more stable results.
Dipyrazolo[1,5-a:4',3'-c]pyridines – a new heterocyclic system accessed via multicomponent reaction
Authors: Holzer Wolfgang , Vilkauskaitė Gytė , Arbačiauskienė Eglė , Šačkus Algirdas
Published: December 2012

The synthesis of dipyrazolo[1,5-a:4',3'-c]pyridines is described. Easily obtainable 5-alkynylpyrazole-4-carbaldehydes, p-toluenesulfonyl hydrazide, and an aldehyde or ketone containing an α-hydrogen atom were reacted in a silver triflate catalyzed multicomponent reaction affording new tricyclic compounds with a dipyrazolo[1,5-a:4',3'-c]pyridine core. Detailed NMR spectroscopic investigations (1H, 13C and 15N) were undertaken with all obtained compounds.
Managing transaction risks in interdependent supply chains: an extended transaction cost economics perspective
Authors: Wever Mark , Wognum Nel , Trienekens Jacques , Omta Onno
Published: December 2012

The present study examines the management of transaction risks in supply chains. Risk management studies often ignore the wider supply chain context in which individual transactions take place. However, risk management strategies which are suitable to use when only a single transaction is considered may be inappropriate when other transactions in the supply chain are taken into account. This study addresses this issue by examining: (1) how risks arise as a result of interdependencies between the various transactions making up the supply chain; and (2) what types of contractual-based strategies actors can use to manage their risk exposure. To realize these aims, the study applies an extended Transaction Cost Economics (TCE) framework with a supply chain orientation. The framework illustrates how different types of interdependencies – pooled, sequential and reciprocal – expose companies to different sources of risk. Three strategies companies can use when facing barriers to risk minimization in sequentially interdependent supply chains are analyzed: risk transferring, risk altering and risk sharing. Examples from the agri-food sector are discussed to demonstrate the functioning of these strategies.
Sustainable supply chain management – the influence of local stakeholder expectations in China’s agri-food industry
Authors: Kao Pao T. , Redekop William H. , Mark-Herbert Cecilia
Published: December 2012

Multinational food processing corporations are facing rapid growth in emerging markets like China and a concurrent need for sustainable supply chain management (SSCM). These firms attempt to address supply risk and threat to the triple bottom line through managing suppliers and inputs, and at the same time need to overcome the uncertainty raised by the unfamiliar host environment. An exploratory qualitative case study of two multinational food processing corporations in China finds their SSCM practices are impacted by the nature of the raw material inputs as well as local stakeholder expectations. In particular, government policy and media attention seems to influence the direction and choice of SSCM activities engaged in by the focal firms. Furthermore, the discussion also suggests a possible permanent effect may occur as stakeholder expectations and host country institutions evolve. The implication of this study is that food processors preparing to enter emerging markets should be aware that local stakeholder expectations may affect operations significantly more than previously expected. As such, these firms need to carefully evaluate their operations in the host market and seek balance between SSCM practices and local stakeholder expectations. This study extends existing research on SSCM, exploring practices among the agri-food industry in a developing economy, and points out a theoretical extension to the existing sustainable purchasing portfolio matrix.
Performance Analysis of Orthogonal Spread Codes for Minimum Essential Communication
Authors: Fu Jie Lin , Qiu Hong Bing
Published: December 2012

By the requirements of reliable wireless communication, a new composite code scheme is proposed for orthogonal spreading codes in order to improve synchronization and error performance, which is based on certain criteria to select the composite codes. Simulation shows that the correlation property of the screened composite codes and the bit error rate performance are better than that of other composite codes.
Research of a Multi-Link Concurrent P2P Communication Model
Authors: Li Jiao , Liu Tian Shi
Published: December 2012

In order to solve the communication efficiency and the load balancing of P2P network, a multi-link concurrent P2P communication model is proposed. It introduces concurrent communication mechanism, assigns proper communication task to all nodes according to the communication capability of nodes and the communication weight between nodes, implements the traffic load balancing and shortens communication time. The model has high concurrency, strong robustness, and effective load balancing, so it is suitable for multicast communication and network data mass transmit.
The Design and Implementation of Shortwave DFH Communication Receiver Based on FPGA
Authors: Zhou Nan , Zhao Xuan , Feng Yong Xin
Published: December 2012

Shortwave DFH system is a new type of communication system, and it is widely used in various fields because of its good anti-interference and anti-fading ability performance in anti-interference and anti-fading. A shortwave DFH communication receiver is designed based on Virtex4-sx35 series FPGA development board using Verilog HDL and VHDL language, and the function of this receiver is implemented and simulated. The result of simulating shows that the designed shortwave DFH receiver is effectively.
A Gigabit Fiber Optical Bus Based on the RapidIO Technology
Authors: Qian Ying Qing , Wang Xiao Feng , Lao Li , Lu Yun
Published: December 2012

The RapidIO architecture is an interconnect technology based on a high-performance and packet-switched interconnect technology. The paper uses the RapidIO Interconnect technology to design a fiber optic bus. The fiber optic bus provides a tightly coupled interconnect with Gigabit speed, which can improve the processing capability of the space distributed system, such as the weapons platform with high-speed and high-capacity multi-system.
A MP2MP-DBA Algorithm in Home Network Based on 60GHz Millimeter-Wave Communication
Authors: Du Cai Li , He Ke , Chen Xue
Published: December 2012

A novel multipoint-to-multipoint bandwidth allocation algorithm named MP2MP-DBA based on 60GHz millimeter-wave communication is proposed for home network. Simulation results show that the MP2MP-DBA achieves better throughput and delay than static bandwidth allocation algorithm.
A Two-Way Relay Channel Estimation Method Based on Sparsity Adaptive Matching Pursuit Algorithm
Authors: Wang Ju Rong , Zhou Jin He
Published: December 2012

To solve the problem that many existing two-way relay channel (TWRC) estimation methods require the sparse degree of the channel as prior information, we introduced a novel iterative greedy reconstruction algorithm based on compressed sensing (CS), called the sparisty adaptive matching pursuit (SAMP) to reconstruct the channel impulse response under orthogonal frequency division multiplexing (OFDM) system. The most innovative feature of SAMP is its capability of channel reconstruction without prior information of the sparse degree. Under the same condition we compared the algorithm with the other channel estimation methods including conventional least square (LS) algorithm, minimum mean square error (MMSE) algorithm and a orthogonal matching pursuit (OMP) algorithm based on CS. Simulation results show that the proposed algorithm has a better estimation performance and the algorithm improves the utilization of communication resources such as spectrum and energy. Thus it is suitable for real application.
Investigation on Fault-Tolerant of 1394b Optical Bus-Based Real-Time Video Transmission
Authors: Long Ying Xue , Zhang Chun Xi , Yi Xiao Su , Wang Ming
Published: December 2012

Reliability is one of the key issues in widely application of real-time video transmission. The fault-tolerant mechanisms of 1394b optical bus protocol are investigated for 1394b optical bus-based real-time video. In addition, a method of hardware redundancy fault-tolerant is proposed. The hardware topology is built with embedded video function nodes, and fault-tolerant control software is realized on VC platform. Furthermore, the 1394b optical bus-based video transmission is demonstrated by experiment, due to which, performances of fault-tolerant for the transmission is evaluated.
Momentum Factor Constant Modulus Algorithm and Theory
Authors: Yang Heng , Wang Jing , Guan Jing , Lu Wei
Published: December 2012

The traditional constant modulus algorithm (CMA) has the disadvantage of slow convergence in blind equalization algorithm. This paper studied one improved algorithm based on momentum factor constant modulus algorithm(MCMA) to solve this problem, momentum factor was added to the weight vector iteration formula of CMA to improve the convergence speed. theoretical analysis and simulation showed that: in the case of the same equalization effect, the MCMA converges faster than the traditional constant modulus algorithm, and also different momentum factors have different convergence effects. The larger the momentum factor , the better convergence effect in the defined domain of the momentum factor.
Optical Spectrum Characteristics of Phase-Only Sampled Chirp Gratings with Manufacturing Errors
Authors: Huang Li Qun , Yang Guang
Published: December 2012

Due to strong coupling among multi-channels of phase-only sampled gratings, the effects of manufacturing errors on sampled grating are different from fiber gratings with a single reflection peak. The influence was investigated by numerical simulation. When group delay and reflectivity ripples are caused by random phase and amplitude errors, inside a grating channel, the ripple amplitude at short wavelength is larger than the one at long wavelength, and this phenomenon was qualitatively explained using the principle that the reflecting position varies with the wavelength of incident light in a chirp grating. The sub-grating length of the transfer matrix method, which is decided by the accuracy of phase mask and UV writing, exerts an influence on the ripple amplitude. For multi-channel fiber gratings, stitch error impairs the periodicity of sampling function, so this kind of fabrication error leads to unequal performance reduction in different channels, and the reduction is more serious for channels at two sides.
P2P Streaming Media Caching Allocation Algorithm Based on 3G Network
Authors: Kang Gui Hua , Li De Guang
Published: December 2012

Now 3G mobile technologies is the research focus in the field of mobile communication. Streaming media technology based on 3G networks is always difficult problems in this field. P2P streaming media technology has become the mainstream application form of internet. In this paper, we design a P2P streaming media cache allocation algorithm based on 3G networks. This algorithm use network protocols to connect 3G network with P2P network to minimize transmission delay and to improve the transmission efficiency. Simulation experiments show that this algorithm presented in this paper has the obvious performance advantage in transmission delay and transmission efficiency.
Research of a New Distributed Trust Model in P2P
Authors: Hao Yan
Published: December 2012

The anonymity and dynamic characters of P2P network make it become hotbed with selfish and malicious behaviors. To improve the wholly quality and security of the network, this paper gives a new distributed trust model to evaluate the trust values of peers which introduces the concept of interaction satisfaction and concerns on both direct and indirect trust. The experiment data shows that this trust model can distinguish good peers and make them have the high ratio of successful interactions.
Research of AODV Protocol Based on Interconnecting MANET and Internet
Authors: Huang Geng Sheng , Zhang Yi , Ma Xin
Published: December 2012

This paper first introduced the related protocol of MANET and mobile IP technology, and then presented the research and implementation of AODV protocol of the dynamic gateway based on the MANET and Internet interconnection, including AODV dynamic gateway, system architecture of dynamic gateway, reform of the AODV protocol, gateway switch and load balance. Finally, it introduced the test environment of the system, and verified through NS2 simulation that the load of the network could be reduced by the improved AODV protocol.
The Design and Implementation of the Content Aggregation and Distribution Platform of New Media for Mobile Terminal
Authors: Liu Li Na , Song Qing , Zhang Peng Zhou
Published: December 2012

Base on the new media service bus of Tianjin Port, aim at the business needs and characteristics of the enterprise, through the digital content aggregation system gathers and manages multimedia resources, through cataloging、processing、storage the aggregated information processed by the content center and retrieve it as an independent source of information for other systems shared-used, Finally, through the distribution of the digital content platform, the powerful route of transmission of the new media to all-round、 three-dimensional report. This platform can distribute text, graphics, images, video and other media means on different media terminals, such as online media, mobile media, making the audience to be able to get more timely, more angles, more audio-visual and personalized communication experience, especially the mobile terminal play a particular advantage to meet user’s demand of accessing and feedback of new information anytime and anywhere.
An Improved Design of the Carrier Communication Digital Multiplexer Implemented on Sports Venues
Authors: Liu Xiao , Zhang Jie
Published: December 2012

The electric carrier communication is the special communicated way of electrical power system In this paper, one kind of double CPU, the low power loss, the low cost digital multiplexer has been designed in conducted the full research to this communicated way, which is satisfied the need of the electric power correspondence transmission system , especially in sports venues. In respect of hardware designing, dual-port RAM and double CPU are adopted for coordinating work and greatly improving efficiency; dual-port RAM , which functions as a shared mailbox of double CPU, is used to store markers, pointer and coordinate the work of double CPU. This article is elaborated the digital multiplexer’s hardware and the software principle of design in detail, carries on the simulation using the monolithic integrated circuit simulator, has achieved the satisfactory effect through the debug .
Ladder Simulation of LC Filter Using OTA-C Filter
Authors: Rao Zhong Yang , Feng Chun Yuan
Published: December 2012

This paper discusses the ladder simulation of the OTA-C filter. The OTA used in the type of filter is given. And the analysis of the implemented steps is introduced in detail. The given example shows that the OTA-C filter can adjust the cutoff frequency and easy to integrate using the method.
An OFDM Channel Estimation Method with Radial Basis Function Neural Network
Authors: He Xiao Wei , Yang Rui Zhe , Zhang Jie , Zhang Yan Hua
Published: December 2012

For OFDM system, we proposed a channel estimation method based on radial basis function neural network (RBFNN). The neural network with Gaussian basis function is established according to the pilot pattern, where the network parameters are obtained by training channel response of pilot subcarriers as objective values for input samples. With the established network, channel coefficients of non-pilot subcarriers can be predicted. The simulation results indicate that the proposed algorithm performs well in OFDM systems under Rayleigh multipath fading channel.
Design and Realization of 10Gbps DPSK System for Free Space Optical Communication
Authors: Wu Gang , Zhang Yan Gan , Yuan Xue Guang , Zhang Jin Nan , Zhang Ming Lun , Li Yu Peng
Published: December 2012

The performance of atmospheric communication system is limited by the atmospheric turbulence. In this paper, we present a practical 10Gbps DPSK transmission system for free space optical (FSO) communication with low error probability and wide-opening eye diagram. Compared to OOK modulation, DPSK format is a more effective way to resist the atmospheric turbulence. In addition, we designed parameters of this modulation system to be varied as the channel situation changed to achieve an optimized performance. The experiment results show that such a DPSK system could greatly overcome the atmospheric turbulence.
Modeling Underwater Time-Varying Acoustic Channel Using OPNET
Authors: Bai Wei Gang , Wang Hai Yan , Zhao Rui Qin
Published: December 2012

Underwater acoustic networks (UWAN) play a crucial role in the development of modern marine military defense and civilian marine. In many cases, the simulation of routing and MAC protocols in underwater acoustic network has ignored the impact of some critical features of complex underwater acoustic channel upon UWAN performances. This paper establishes a channel model for the Rayleigh fading channel in shallow-water medium-range communication in OPNET network simulation software. It simulates the time-varying and multi-path effects of underwater acoustic channel, which are reflected in the received power and bit error rate. Finally the validity of this channel model is verified by simulations.