bluuebunny/crossref_metadata_2025 huggingface dataset:
Stat and interferon genes identified by network analysis differentially regulate primitive and definitive erythropoiesis
Authors: Greenfest-Allen Emily , Malik Jeffrey , Palis James , Stoeckert Christian J
Published: May 2013

Background

Hematopoietic ontogeny is characterized by overlapping waves of primitive, fetal definitive, and adult definitive erythroid lineages. Our aim is to identify differences in the transcriptional control of these distinct erythroid cell maturation pathways by inferring and analyzing gene-interaction networks from lineage-specific expression datasets. Inferred networks are strongly connected and do not fit a scale-free model, making it difficult to identify essential regulators using the hub-essentiality standard.

Results

We employed a semi-supervised machine learning approach to integrate measures of network topology with expression data to score gene essentiality. The algorithm was trained and tested on the adult and fetal definitive erythroid lineages. When applied to the primitive erythroid lineage, 144 high scoring transcription factors were found to be differentially expressed between the primitive and adult definitive erythroid lineages, including all expressed STAT-family members. Differential responses of primitive and definitive erythroblasts to a Stat3 inhibitor and IFNγ in vitro supported the results of the computational analysis. Further investigation of the original expression data revealed a striking signature of Stat1-related genes in the adult definitive erythroid network. Among the potential pathways known to utilize Stat1, interferon (IFN) signaling-related genes were expressed almost exclusively within the adult definitive erythroid network.

Conclusions

In vitro results support the computational prediction that differential regulation and downstream effectors of STAT signaling are key factors that distinguish the transcriptional control of primitive and definitive erythroid cell maturation.
Degradation of progestagens by oxidation with potassium permanganate in wastewater effluents
Authors: Fayad Paul B , Zamyadi Arash , Broseus Romain , Prévost Michèle , Sauvé Sébastien
Published: May 2013

Background

This study investigated the oxidation of selected progestagenic steroid hormones by potassium permanganate at pH 6.0 and 8.0 in ultrapure water and wastewater effluents, using bench-scale assays. Second order rate constants for the reaction of potassium permanganate with progestagens (levonorgestrel, medroxyprogesterone, norethindrone and progesterone) was determined as a function of pH, presence of natural organic matter and temperature. This work also illustrates the advantages of using a novel analytical method, the laser diode thermal desorption (LDTD-APCI) interface coupled to tandem mass spectrometry apparatus, allowing for the quick determination of oxidation rate constants and increasing sample throughput.

Results

The second-order rate constants for progestagens with permanganate determined in bench-scale experiments ranged from 23 to 368 M-1 sec-1 in both wastewater and ultrapure waters with pH values of 6.0 and 8.0. Two pairs of progestagens exhibited similar reaction rate constants, i.e. progesterone and medroxyprogesterone (23 to 80 M-1 sec-1 in ultrapure water and 26 to 149 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0) and levonorgestrel and norethindrone (179 to 224 M-1 sec-1 in ultrapure water and 180 to 368 M-1 sec-1 in wastewaters, at pH 6.0 and 8.0). The presence of dissolved natural organic matter and the pH conditions improved the oxidation rate constants for progestagens with potassium permanganate only at alkaline pH. Reaction rates measured in Milli-Q water could therefore be used to provide conservative estimates for the oxidation rates of the four selected progestagens in wastewaters when exposed to potassium permanganate. The progestagen removal efficiencies was lower for progesterone and medroxyprogesterone (48 to 87 %) than for levonorgestrel and norethindrone (78 to 97%) in Milli-Q and wastewaters at pH 6.0-8.2 using potassium permanganate dosages of 1 to 5 mg L-1 after contact times of 10 to 60 min.

Conclusion

This work presents the first results on the permanganate-promoted oxidation of progestagens, as a function of pH, temperature as well as NOM. Progestagen concentrations used to determine rate constants were analyzed using an ultrafast laser diode thermal desorption interface coupled to tandem mass spectrometry for the analysis of water sample for progestagens.
A study on dispersion and characterisation of α-mangostin loaded pH sensitive microgel systems
Authors: Ahmad Madihah , Yamin Bohari M , Mat Lazim Azwan
Published: May 2013

Background

α-Mangostin was extracted with methanol from the rind of mangosteen fruit and purified by using silica gel column chromatography technique. The compound is characterised using infrared, 13C and 1H NMR as well as UV–vis spectroscopy. The α-mangostin dispersion in colloidal systems was studied by incorporating it with an ionic microgel, poly (N-Isopropylacrylamide)-co-2VP at different pH.

Result

The DLS result showed the size of microgel-α-mangostin mixture declined from 548 nm to 200 nm upon the increment of the pH. Moreover, it was found the morphology of loaded compound depended largely on the nature of the continuous phase of the microgel system. Interestingly, by manipulating the pH, α-mangostin tends to form crystal at extremely low pH and transforms into spherical shapes at pH 6.

Conclusion

This research shows different structures of the α-mangostin particle that are attributed by adjusting the pH using microgel systems as a template.
An unexpected role of neuroligin-2 in regulating KCC2 and GABA functional switch
Authors: Sun Chicheng , Zhang Lei , Chen Gong
Published: May 2013

Background

GABAA receptors are ligand-gated Cl- channels, and the intracellular Cl- concentration governs whether GABA function is excitatory or inhibitory. During early brain development, GABA undergoes functional switch from excitation to inhibition: GABA depolarizes immature neurons but hyperpolarizes mature neurons due to a developmental decrease of intracellular Cl- concentration. This GABA functional switch is mainly mediated by the up-regulation of KCC2, a potassium-chloride cotransporter that pumps Cl- outside neurons. However, the upstream factor that regulates KCC2 expression is unclear.

Results

We report here that KCC2 is unexpectedly regulated by neuroligin-2 (NL2), a cell adhesion molecule specifically localized at GABAergic synapses. The expression of NL2 precedes that of KCC2 in early postnatal development. Upon knockdown of NL2, the expression level of KCC2 is significantly decreased, and GABA functional switch is significantly delayed during early development. Overexpression of shRNA-proof NL2 rescues both KCC2 reduction and delayed GABA functional switch induced by NL2 shRNAs. Moreover, NL2 appears to be required to maintain GABA inhibitory function even in mature neurons, because knockdown NL2 reverses GABA action to excitatory. Gramicidin-perforated patch clamp recordings confirm that NL2 directly regulates the GABA equilibrium potential. We further demonstrate that knockdown of NL2 decreases dendritic spines through down-regulating KCC2.

Conclusions

Our data suggest that in addition to its conventional role as a cell adhesion molecule to regulate GABAergic synaptogenesis, NL2 also regulates KCC2 to modulate GABA functional switch and even glutamatergic synapses. Therefore, NL2 may serve as a master regulator in balancing excitation and inhibition in the brain.
Biogenic trypanocidal sesquiterpenes: lead compounds to design future trypanocidal drugs - a mini review
Authors: Saeidnia Soodabeh , Gohari Ahmad Reza , Haddadi Azita
Published: May 2013

Human trypanosomiasis is a parasitic disease among poor people in Africa and Latin America. Therapy against African and American trypanosomiasis is based on a few drugs that often cause severe side-effects. Therefore, it is essential to develop drug discovery especially from natural origins. Sesquiterpenes, a diverse group of natural terpenoids, are found in essential oils of many plants and show a broad range of bioactivities. They act through multiple mechanisms in the chemotherapy of trypanosomiasis. Some of these active compounds contain hydroperoxides, aldehydes, alcohols, α,β-unsaturated γ-lactone and even halogenated moieties. Among the compounds reported, sesquiterpene lactones showed a potent anti-trypanosoma effect comparable with commercial trypanocidal drugs. Trypanocidal activity of sesquiterpene lactones mostly depends on the reaction between γ-lactone moieties and nucleophile groups of trypanithione, which is essential for Trypanosoma defense against the oxidative stresses. Elatol is a sesquiterpenoid from marine algae, with a different structure and considerable trypanocidal activity which could be an interesting candidate for further antiprotozoal investigations. To develop novel drugs with higher efficacy and lower toxicity from natural products, this review summarizes the more recent information on trypanocidal activities of various sesquiterpenes.
Co-occurrence of anaerobic bacteria in colorectal carcinomas
Authors: Warren René L , Freeman Douglas J , Pleasance Stephen , Watson Peter , Moore Richard A , Cochrane Kyla , Allen-Vercoe Emma , Holt Robert A
Published: May 2013

Background

Numerous cancers have been linked to microorganisms. Given that colorectal cancer is a leading cause of cancer deaths and the colon is continuously exposed to a high diversity of microbes, the relationship between gut mucosal microbiome and colorectal cancer needs to be explored. Metagenomic studies have shown an association between Fusobacterium species and colorectal carcinoma. Here, we have extended these studies with deeper sequencing of a much larger number (n = 130) of colorectal carcinoma and matched normal control tissues. We analyzed these data using co-occurrence networks in order to identify microbe-microbe and host-microbe associations specific to tumors.

Results

We confirmed tumor over-representation of Fusobacterium species and observed significant co-occurrence within individual tumors of Fusobacterium, Leptotrichia and Campylobacter species. This polymicrobial signature was associated with over-expression of numerous host genes, including the gene encoding the pro-inflammatory chemokine Interleukin-8. The tumor-associated bacteria we have identified are all Gram-negative anaerobes, recognized previously as constituents of the oral microbiome, which are capable of causing infection. We isolated a novel strain of Campylobacter showae from a colorectal tumor specimen. This strain is substantially diverged from a previously sequenced oral Campylobacter showae isolate, carries potential virulence genes, and aggregates with a previously isolated tumor strain of Fusobacterium nucleatum.

Conclusions

A polymicrobial signature of Gram-negative anaerobic bacteria is associated with colorectal carcinoma tissue.
Cross-linked enzyme aggregates (CLEAs) of selected lipases: a procedure for the proper calculation of their recovered activity
Authors: Guauque Torres María del Pilar , Foresti María Laura , Ferreira María Luján
Published: May 2013

In the last few years, synthesis of carrier-free immobilized biocatalysts by cross-linking of enzyme aggregates has appeared as a promising technique. Cross-linked enzyme aggregates (CLEAs) present several interesting advantages over carrier-bound immobilized enzymes, such as highly concentrated enzymatic activity, high stability of the produced superstructure, important production costs savings by the absence of a support, and the fact that no previous purification of the enzyme is needed. However, the published literature evidences that a) much specific non-systematic exploratory work is being done and, b) recovered activity calculations in CLEAs still need to be optimized. In this context, this contribution presents results of an optimized procedure for the calculation of the activity retained by CLEAs, based on the comparison of their specific activity relative to their free enzyme counterparts. The protocol implies determination of precipitable protein content in commercial enzyme preparations through precipitation with ammonium sulphate and a protein co-feeder. The identification of linear ranges of activity versus concentration/amount of protein in the test reaction is also required for proper specific activity determinations. By use of mass balances that involve the protein initially added to the synthesis medium, and the protein remaining in the supernatant and washing solutions (these last derived from activity measurements), the precipitable protein present in CLEAs is obtained, and their specific activity can be calculated. In the current contribution the described protocol was applied to CLEAs of Thermomyces lanuginosa lipase, which showed a recovered specific activity of 11.1% relative to native lipase. The approach described is simple and can easily be extended to other CLEAs and also to carrier-bound immobilized enzymes for accurate determination of their retained activity.
The expression and significance of insulin-like growth factor-1 receptor and its pathway on breast cancer stem/progenitors
Authors: Chang Wen-Wei , Lin Ruey-Jen , Yu John , Chang Wen-Ying , Fu Chiung-Hui , Lai Alan Chuan-Ying , Yu Jyh-Cherng , Yu Alice L
Published: May 2013

Introduction

Dysregulation of the insulin-like growth factor-1 receptor (IGF-1R)/phosphatidylinositol-3-kinase (PI3K)/Akt pathway was shown to correlate with breast cancer disease progression. Cancer stem cells are a subpopulation within cancer cells that participate in tumor initiation, radio/chemoresistance and metastasis. In breast cancer, breast cancer stem cells (BCSCs) were identified as CD24-CD44+ cells or cells with high intracellular aldehyde dehydrogenase activity (ALDH+). Elucidation of the role of IGF-1R in BCSCs is crucial to the design of breast cancer therapies targeting BCSCs.

Methods

IGF-1R expression in BCSCs and noncancer stem cells sorted from xenografts of human primary breast cancers was examined by fluorescence-activated cell sorting (FACS), western blot analysis and immunoprecipitation. The role of IGF-1R in BCSCs was assessed by IGF-1R blockade with chemical inhibitor and gene silencing. Involvement of PI3K/Akt/mammalian target of rapamycin (mTOR) as the downstream pathway was studied by their phosphorylation status upon IGF-1R inhibition and the effects of chemical inhibitors of these signaling molecules on BCSCs. We also studied 16 clinical specimens of breast cancer for the expression of phosphor-Akt in the BCSCs by FACS.

Results

Expression of phosphorylated IGF-1R was greater in BCSCs than in non-BCSCs from xenografts of human breast cancer, which were supported by western blot and immunoprecipitation experiments. The sorted IGF-1R-expressing cells displayed features of cancer stem/progenitors such as mammosphere formation in vitro and tumorigenicity in vivo, both of which were suppressed by knockdown of IGF-1R. A specific inhibitor of the IGF-1R, picropodophyllin suppressed phospho-AktSer473 and preferentially decreased ALDH+ BCSC populations of human breast cancer cells. Furthermore, picropodophyllin inhibited the capacity of CD24-CD44+ BCSCs to undergo the epithelial-mesenchymal transition process with downregulation of mesenchymal markers. Inhibitors of signal molecules downstream of IGF-1R including PI3K/Akt/mTOR also reduced the ALDH+ population of breast cancer cells. Furthermore, the mTOR inhibitor, rapamycin, suppressed BCSCs in vitro and in vivo.

Conclusion

Our data support the notion that IGF-1R is a marker of stemness, and IGF-1R and its downstream PI3K/Akt/mTOR pathway are attractive targets for therapy directed against breast cancer stem/progenitors.
Parenteral diclofenac infusion significantly decreases brain-tissue oxygen tension in patients with poor-grade aneurysmal subarachnoid hemorrhage
Authors: Schiefecker Alois J , Pfausler Bettina , Beer Ronny , Sohm Florian , Sabo Jan , Knauseder Viktoria , Fischer Marlene , Dietmann Anelia , Hackl Werner O , Thomé Claudius , Schmutzhard Erich , Helbok Raimund
Published: May 2013

Introduction

Diclofenac, a nonsteroidal antiinflammatory drug, is commonly used as antipyretic therapy in intensive care. The purpose of this study was to investigate the effects of parenteral diclofenac infusion on brain homeostasis, including brain-tissue oxygen tension (PbtO2) and brain metabolism after aneurysmal subarachnoid hemorrhage (aSAH).

Methods

We conducted a prospective, observational study with retrospective analysis of 21 consecutive aSAH patients with multimodal neuromonitoring. Cerebral perfusion pressure (CPP), mean arterial pressure (MAP), intracranial pressure (ICP), body temperature, and PbtO2 were analyzed after parenteral diclofenac infusion administered over a 34-minute period (20 to 45 IQR). Data are given as mean ± standard error of mean and median with interquartile range (IQR), as appropriate. Time-series data were analyzed by using a general linear model extended by generalized estimation equations (GEEs).

Results

One-hundred twenty-three interventions were analyzed. Body temperature decreased from 38.3°C ± 0.05°C by 0.8°C ± 0.06°C (P < 0.001). A 10% decrease in MAP and CPP (P < 0.001) necessitated an increase of vasopressors in 26% (n = 32), colloids in 33% (n = 41), and crystalloids in 5% (n = 7) of interventions. PbtO2 decreased by 13% from a baseline value of 28.1 ± 2.2 mm Hg, resulting in brain-tissue hypoxia (PbtO2 <20 mm Hg) in 38% (n = 8) of patients and 35% (n = 43) of interventions. PbtO2 <30 mm Hg before intervention was associated with brain-tissue hypoxia after parenteral diclofenac infusion (likelihood ratio, 40; AUC, 93%; 95% confidence interval (CI), 87% to 99%; P < 0.001). Cerebral metabolism showed no significant changes after parenteral diclofenac infusion.

Conclusions

Parenteral diclofenac infusion after aSAH effectively reduces body temperature, but may lead to CPP decrease and brain-tissue hypoxia, which were both associated with poor outcome after aSAH.
Dietary Vitamin D Restriction in Pregnant Female Mice Is Associated With Maternal Hypertension and Altered Placental and Fetal Development
Authors: Liu Nancy Q. , Ouyang Yi , Bulut Yasemin , Lagishetty Venu , Chan Shiao Y. , Hollis Bruce W. , Wagner Carol , Equils Ozlem , Hewison Martin
Published: May 2013

Epidemiology has linked vitamin D deficiency with preeclampsia in humans. We hypothesized that low vitamin D status in pregnant mice may lead to symptoms of preeclampsia. Female BL6 mice were raised on vitamin D-sufficient or -deficient diets from weeks 4 of age and then mated with vitamin D-sufficient BL6 males at week 8. The resulting pregnant mice were either allowed to deliver pups and monitored for blood pressure (BP) and weight of offspring or euthanized at day 14 or 18 of gestation (E14 or E18) for analysis of serum, placental/kidney tissues, and fetuses. At E14 serum concentrations of 25-hydroxyvitamin D (30.1 ± 5.0 vs 1.8 ± 0.6 ng/mL, P < .001) and 1,25-dihydroxyvitamin D (119.5 ± 18.7 vs 37.4 ± 5.1 pg/mL, P < .01) were higher in sufficient vs deficient pregnant mice. At E14 BP was significantly elevated in vitamin D-deficient pregnant mice relative to vitamin D-sufficient mice for both systolic BP (124.89 ± 2.28 vs 105.34 ± 3.61 mm Hg, P < .001) and mean arterial pressure (115.33 ± 1.93 vs 89.33 ± 5.02 mm Hg, P < .001). This elevation continued through pregnancy until 7 days postpartum (PP7) but returned to baseline by PP14. Analysis of maternal kidneys showed increased expression of mRNA for renin and the angiotensin II receptor (3- and 4-fold, respectively) in vitamin D-deficient vs -sufficient mice at E14. Histological analysis of E14 placentas from vitamin D-deficient mice showed decreased vascular diameter within the labyrinth region. E14 and E18 fetuses from vitamin D-deficient mice were larger than those from vitamin D-sufficient mothers. However, by PP14 pups from vitamin D-deficient mothers weighed significantly less than those from vitamin D-sufficient mothers. Resupplementation of vitamin D periconceptually partially reversed the effects of vitamin D deficiency. These data provide further evidence that low vitamin D status may predispose pregnant women to dysregulated placental development and elevated blood pressure.
The Physics of Holy Oats: Vernacular Knowledge, Qualities, and Remedy in Fifteenth-Century England
Authors: Milner Matthew
Published: May 2013

Recent work in historical philosophy on the Aristotelian concept of qualities — that is, hot, cold, wet, and dry, the fundamental causal agents of the natural world — offers a moment to reconsider the connections between medicine, religion, and natural philosophy in late medieval England. Though hidden and obscure to most modern scholars, how qualities operated in contemporary remedies, such as those for horses suffering from founder, raises questions about the nature of vernacular knowledge of philosophical and theological concepts and their relation to lived everyday life. We not only find connections between grace and physics, but that knowledge of the physics of qualities brings considerable nuance to why men and women used holy words, objects, and actions as ingredients in cures. Standing alongside the extensive scholarship on magic and the supernatural, this article illustrates how understandings of qualities were central to the contestations over rationality and vernacularity in fifteenth-century culture.
Models for Type VI Adsorption Isotherms from a Statistical Mechanical Formulation
Authors: Yahia M. Ben , Torkia Y. Ben , Knani S. , Hachicha M. A. , Khalfaoui M. , Lamine A. Ben
Published: May 2013

In this study, two theoretical expressions for the Type VI isotherm in the IUPAC classification are presented. The formulation of these new expressions is based on a rigorous statistical mechanical description. The expressions allow for the estimation of physicochemical parameters within the theoretical model. The proposed models allow a good correlation to Type VI experimental isotherms taken from the literature such as adsorption isotherms for adsorption of methane onto MgO (100) and onto an exfoliated graphite surface. The parameters intervening in the adsorption process have been deduced directly from experimental adsorption isotherms by numerical simulation. The theoretical expressions provide an understanding and interpretation of the adsorption isotherms at the microscopic level.
A Phenomenological Interpretation of Two-Step Adsorption Kinetics of Humic Acids on Zeolitic Tuff
Authors: Ambrosone Luigi , Canzano Silvana , Iovino Pasquale , Salvestrini Stefano , Capasso Sante , Colella Carmine
Published: May 2013

In this study, the kinetics of adsorption of humic acid (HA) from aqueous solution onto a zeolitic tuff were investigated. X-ray diffraction, scanning electron microscopy, porosity and pore-size distribution measurements indicate that macromolecules can diffuse into the material. The kinetic curves show a two-stage adsorption. The adsorbed amount increases up to 2 days, remains constant and then increases again to attain equilibrium. There is a remarkable similarity between this adsorption behaviour of HA on zeolitic tuff and the behaviour observed when ultrathin multi-layers of polymeric materials are fabricated by self-assembly technique. Experiments reveal two distinct stages: the first corresponds to the macromolecules being driven towards the substrate, while the second is the result of arrangement of macromolecules. The first stage is a first-order kinetics with characteristic lifetime of 1–2 days, whereas the second stage is a Johnson–Mehl–Avrami function with (tm) in the exponential and slower characteristic lifetime.
Active Acoustic Systems for the Control of Room Acoustics
Authors: Poletti M. A.
Published: May 2013

The acoustic design of auditoria involves the specification of the room geometry and boundary properties, and any additional acoustic elements such as reflectors or diffusers, to usefully direct sound to produce a desired subjective experience, quantified by measurable acoustic parameters. This design must take into account the reflection of sound within the stage area, the early reflections from the stage to the audience and the reverberant response of the room. The sound produced by the audience can also be an important consideration. Active acoustic systems provide an alternative approach to controlling subjective experience. They use microphones, electronic processors and loudspeakers to create reflections and reverberation in addition to those produced by the naturally-occurring sound field. The acoustic properties can be changed instantly, and the enhanced acoustic properties of the auditorium can typically be varied over a wider range than can be produced by variable passive techniques. The design of active acoustics follows that of passive approaches, but rather than the physical arrangement of the room surfaces, it commences with an existing passive space with some minimum acoustic condition, and requires the arrangement of microphones to detect relevant sound and the choice of processors and loudspeaker positions to direct it usefully back into the room to produce a desired set of acoustic parameters. While active systems have historically been developed with the goal of enhancing either the stage or audience sound, they must generally provide the same control of sound as passive acoustic design. This paper discusses the principles of active acoustic systems and how they are used to achieve the required range of control. A survey of current commercial systems is given and some implications for the future of live performance are explored.
Polypropylene Fibre Reinforced Concrete-Stainles Steel Composite Columns: Design and Behaviour
Authors: Ellobody Ehab , Ghazy Mariam F.
Published: May 2013

This paper investigates the design and behaviour of polypropylene fibre reinforced (FR) concrete-stainless steel pin-ended composite columns through experimental investigation. The stainless steel tubes used in the composite column tests had an external diameter-to-plate thickness ( D/ t) ratio of 50. The composite columns had different lengths varied from 3 D to 12 D and nondimensional slenderness varied from 0.13 to 0.52, respectively. Overall, the investigation aimed to explore the structural benefits of using a composite material such as polypropylene fibre reinforced concrete in filling stainless steel circular tubes for the use in composite construction sector. The study has shown that FR concrete-filled stainless steel tubular columns offer a considerable increase in column ductility compared with plain concrete-filled tubular columns. The test ultimate loads were compared with the design ultimate loads calculated using the Eurocode 4 for composite columns. Generally, it has been shown that the EC4 accurately predicted the ultimate loads of axially loaded concrete-filled stainless steel circular tubular columns, but were quite conservative for predicting the ultimate loads of the eccentrically loaded columns. It has also been shown that the conservatism of the EC4 predictions is increased as the eccentricity is increased. Based on the test results a modification was proposed to improve the EC4 design guides.
Experimental Study of Moderately Reinforced Concrete Beams Strengthened with Bolted-Side Steel Plates
Authors: Li L.Z. , Lo S.H. , Su R.K.L.
Published: May 2013

Existing reinforced concrete (RC) beams can be effectively strengthened by attaching steel plates to the side faces of the beams using anchor bolts. The performance of this type of beam, bolted side-plated (BSP) beams, is mainly controlled by the degree of partial interaction at the steel-concrete interface. In this study, a total of seven moderately reinforced BSP beams with different steel plate depths and various bolt spacings were tested. Their behaviours were compared to the available test results for lightly reinforced BSP beams obtained by other researchers. The results show that moderately reinforced RC beams are more effective in increasing the flexural strength and ductility capacity using deeper steel plates than the use of a greater number of anchor bolts. It was also found that the longitudinal and transverse slips were controlled by both the stiffness ratios of the steel plates to the RC beam and the force-slip response of the anchor bolts.
Multi-Physics Blast Analysis for Steel-Plated and GFRP-Plated Concrete Panels
Authors: Yun Sung-Hwan , Park Taehyo
Published: May 2013

The blast damage behaviors of steel-plated and glass fiber reinforced polymer (GFRP)-plated concrete panels exposed to explosive are investigated. In order to improve efficiency and accuracy of numerical analysis, the multi-physics method of coupled Eulerian-Lagrangian discretization is used. To enhance the reliability of the simulation results, the equation of state, strength, and failure model of materials are implemented in an explicit program, AUTODYN. In particular, the implemented formulation includes the strain rate-dependent plasticity for concrete and a transversely isotropic elastic constitutive model for GFRP. The retrofitted concrete panels are compared to non-retrofitted concrete panels, and the deflection and deflection ratio are reduced by steel and GFRP plates. To validate the implemented material models and analysis method, a comparison is made with the reported experimental results. The maximum deflection of the panel from the numerical analysis agrees closely with the results of the experiments. Finally, a discussion of the numerical results with respect to code criteria and energy absorption capacity is presented.
3D FEM Analysis of Pounding Response of Bridge Structures at a Canyon Site to Spatially Varying Ground Motions
Authors: Bi Kaiming , Hao Hong , Chouw Nawawi
Published: May 2013

Previous studies of pounding responses of adjacent bridge structures under seismic excitation were usually based on the simplified lumped mass model or beam-column element model. Consequently, only 1D point to point pounding, which is usually in the longitudinal direction of the bridge, could be considered. In reality, pounding could occur along the entire surfaces of the adjacent bridge structures. Moreover, spatially varying transverse ground motions generate torsional responses of bridge decks and these responses may cause eccentric poundings. That is why many pounding damages occurred at corners of the adjacent decks as observed in almost all previous major earthquakes. A simplified 1D model cannot capture torsional response and eccentric poundings. To more realistically investigate pounding between adjacent bridge structures, a two-span simply-supported bridge structure located at a canyon site is established with a detailed 3D finite element model in the present study. Spatially varying ground motions in the longitudinal, transverse and vertical directions at the bridge supports are stochastically simulated as inputs in the analysis. The pounding responses of the bridge structure under multi-component spatially varying ground motions are investigated in detail by using the finite element code LS-DYNA. Numerical results show that the detailed 3D finite element model clearly captures the eccentric poundings of bridge decks, which may induce local damage around the corners of bridge decks. It demonstrates the necessity of detailed 3D modelling for a more realistic simulation of pounding responses of adjacent bridge decks to earthquake excitations.
Shear Behavior of Large Reinforced Concrete Beams without Web Reinforcement
Authors: Yu Lei , Che Yi , Song Yupu
Published: May 2013

This study presents an investigation on the influence of beam depth and longitudinal reinforcement ratio on shear strength. Seven reinforced concrete beams without web reinforcement with depth varying from 500 mm to 1200 mm were tested. Maximum shear crack width, crack spacing and inclinations of shear cracks were measured and shear mechanism of concrete was discussed. In addition, other shear test data found in the literature were used to supplement the experimental data. Based on test results, the shear design methods in the GB50010 code and the ACI 318 code were examined. It was found that the size effect factor in the GB50010 shear design equations was unable to represent the reduction of shear strength for large beams due to the size effect, and that both the GB50010 method and the ACI 318 method are dangerously unconservative when applied to large beams or to beams with low longitudinal reinforcement ratio. The CSA 2004 code method developed based on the Modified Compression Field Theory was also used to analysis the test data and satisfactory results were achieved.
Study of the Anchorage Connections for Buckling Restrained Braces Part 2: Theoretical Study
Authors: Guo Xiao-Kang , Li Guo-Qiang , Sun Fei-Fei , Liu Yu-Shu
Published: May 2013

This paper investigates behaviors of the anchorage connections for buckling restrained braces (BRBs). Finite element (FE) models are established by using software ABAQUS to simulate some tests reported in Part 1 of the companion papers. The material nonlinearities of concrete, anchor bars and anchor plates with the contact property between them are considered in the FE models. A numerical formula is developed for predicting the shear stiffness of anchor bars based on the results from the parametric study using ABAQUS. A formula dealing with the tensile stiffness of the anchor bars is presented relied on the theoretical study. Both of the proposed formulas are verified with the test results. Some design suggestions of the anchorage connections for buckling restrained braces are presented on the basis of the theoretical and experimental studies.
On a New Interpretation of Fuzzy C Mean Using Quantum Theory
Authors: Li Zhihua
Published: May 2013

A quantum mechanics interpretation of Fuzzy C-Mean (FCM) is presented. Cluster aims to study the data distribution in scale space. Its characteristics are very similar to the particle world in quantum physics. By analyzing the essence of the quantum potential and the quantum trap, the paper discusses the core and the basis of Quantum Clustering in quantum mechanics. A couple of drawbacks about Quantum Clustering algorithm is also presented. In addition, known from the fuzzy mathematical computing, the important fuzzy similarity parameter u in FCM is expressed by the quantum wave function. After a series of analysis, the important six innovation conclusions about Iris, FCM, and Quantum Clustering are proposed, and one of the most important is that there is a cryptical wave function existing in FCM, as well as several important experimental results prove it.
On the Effective Region of Convergence of the Decomposition Series Solution
Authors: Duan Jun-Sheng , Rach Randolph , Wang Zhong
Published: May 2013

In this paper we investigate the domain of convergence of the Adomian series solution based on the computational results for several examples. We demonstrate how the domain of convergence can be extended by introducing a parameter c in the definition of the zeroth-order and first-order solution components u0 and u1. Furthermore we generalize the concept of the convergence parameter c from a two-term partition of the initial condition to a multiple-term partition with the design of expanding the domain of convergence of the Adomian series solutions for nonlinear differential equations.
Inuenta est blandae rationis imago : Visualizing the Mausoleum of the Flavii
Authors: Pillinger Emily
Published: May 2013

The North African mausoleum of the Flavii family hosts a remarkable verse inscription that interrogates the relationship between writing and architecture by exploring a range of spatial and temporal dynamics. The poetry invites its audience to "visualize" the monument through a process that includes viewing the building's architectural language, reading the inscribed poetry as "literature," and constructing mental images in response to both stimuli. This visualization process, which also requires the audience to imagine the voices of various different characters involved in commissioning, constructing, and commenting on the monument, enacts a powerful form of commemoration.
Mutata corpora : Ovid's Changing Forms and the Metamorphic Bodies of Pantomime Dancing
Authors: Lada-Richards Ismene
Published: May 2013

This article reads Ovid's foregrounding of the human body in the Metamorphoses side by side with the most flamboyant public discourse of Augustan Rome where the body was similarly privileged as a medium of communication, namely pantomime dancing, an expression-filled dance form predicated on the mute delineation of character and passion. Ovid's body-centered poetic vision is informed by the haunting materiality of the staged, dancing body, whose electrifying language had a searing effect on his literary imagination. Reading the Metamorphoses through the lens of pantomime dancing illuminates the profound, albeit underexplored, symbiosis of dance and poetry in Augustan Rome.
Courting the Erinyes: Persuasion, Sacrifice, and Seduction in Aeschylus's Eumenides
Authors: Rynearson Nicholas
Published: May 2013

At the end of the Eumenides , Athena draws on the discourses of propitiatory sacrifice and amatory persuasion in order to successfully persuade the Erinyes to give up their wrath and accept cult honors in Athens. Athena thus founds the cult of the Semnai with an act of rhetorical propitiation and, through the erotic element of her persuasive speech, offers the Erinyes the surprising role of beloved objects, who will be "wooed" by the Athenians in imitation of her own gentle persuasion.
Homer and the Epic Cycle in Ovid, Heroides 16-17
Authors: Mazurek Elizabeth Forbis
Published: May 2013

This essay discusses the Cypria and the Iliad as important background texts for Ovid, Heroides 16-17, the correspondence of Paris and Helen. It argues that Paris and Helen offer different literary perspectives of their potential elopement and its cause—the Judgment of Paris—which reflect the Cypria and the Iliad , respectively. These letters thus dramatize a narrative cause and effect between Cypria and Iliad at the same time that they underscore stylistic and thematic contrasts between the two poems.
A Hero's Welcome: Homecoming and Transition in the Trachiniae
Authors: Kratzer Emily
Published: May 2013

The nostos ("homecoming") of Heracles in Sophocles' Trachiniae figures as the triumphal return of a victorious athlete. Under ideal circumstances, nostos culminates in the joyous remarriage of husband and wife, but in Trachiniae , reversals that befall Heracles and Deianeira transform the hero's triumphant nostos into a spectacle of death. While the failed nostos motif heralds disaster and effects a decisively bleak atmosphere throughout the play's much-discussed ending, it also nods toward a more positive tradition concerning Heracles' end, since both vase-painting and early poetic accounts portray Heracles' apotheosis-featuring marriage to Hebe and reception into Zeus's household-as a homecoming.
Contesting the Lessons from the Past: Aeschines' Use of Social Memory
Authors: Steinbock Bernd
Published: May 2013

Against tendencies of viewing the orators' historical allusions as empty rhetorical phrases or manipulative cover-ups for Realpolitik this study of historical paradigms in the debate over the Peace of Philocrates argues that the past constituted political capital in its own right. Using theories of social memory, it contextualizes Aeschines' and his opponents' historical examples within the Athenian memorial framework and thus tries to gauge their ideological and emotive weight. Drawing on family memories, Aeschines effectively challenged the Athenian master narrative by linking the rejection of a reasonable Spartan peace offer to the traumatic memories of total defeat and the terror regime of the Thirty.
The Reflections of Satire: Lucian and Peregrinus
Authors: Fields Dana
Published: May 2013

The Death of Peregrinus is ostensibly an attack on the eponymous sham philosopher and holy man, but when one looks more closely at how this attack is constructed, other targets emerge. This article argues that Lucian carries out his satire in terms that lead the reader back to his own authorial persona and implicate him in the same desperate striving for fame. But Lucian is not simply undermining himself nihilistically; instead the work becomes a satire on the culture of agonistic display in which both figures were so deeply invested.
Climate Change and the Caribbean: Review and Response
Authors: Taylor Michael A. , Stephenson Tannecia S. , Chen A. Anthony , Stephenson Kimberly A.
Published: May 2013

Les économies des pays caribéens, les modes de vie, les activités, les pratiques et les cycles opérationnels sont intimement liés au climat, à cause de la vulnérabilité de ces sociétés face aux changements climatiques et/ou aux variations de ces deniers. Les extrêmes climatiques affectent l’agriculture, la pêche, la santé, le tourisme, l’approvisionnement en eau, la consommation d’énergie, pour ne citer que quelques exemples. Cependant, peu d’importance est accordé au climat dans les plans de développement à long terme, ni dans le développement des politiques publiques de la région. Ceci est dû en partie à un manque de connaissance sur le changement climatique, sa probable manifestation dans la région et son possible impact dans les sociétés caribéennes. Cet article présente une vue d’ensemble de la croissante banque de connaissances sur la science du climat caribéen ; ses changements et ses variabilités. On propose une brève description des éléments fondamentaux de la science qui étudie le changement climatique, les tendances passées et les projections futures pour le climat dans la Caraïbe, ainsi que les menaces que représentent les changements climatiques, tout en considérant que tenant compte la science climatique caribéenne dispose suffisamment de données récentes. En outre, on présente un aperçu général de la façon dont le problème climatique pourrait être abordé.
Caribbean Agriculture in a Period of Global Change: Vulnerabilities and Opportunities
Authors: Barker David
Published: May 2013

Les tendances, en matière de développement agricole dans les îles de la Caraïbe, sont de plus en plus relatives aux changements globaux. Ces changements globaux se composent de deux paramètres: la globalisation et les changements environnementaux. Nous pouvons identifier de façon particulière les tensions ainsi que les impacts liés à de la libéralisation du commerce et les aux risques environnementaux. En ce qui a trait à ces derniers, l’augmentation apparente des conditions météorologiques extrêmes (précisément lors des périodes spéciales de sécheresse prolongée et de pluies intenses) représente de possible présages de changements climatiques. Ces facteurs ont eu des répercussions sur toute la région, spécialement sur l’agriculture d’exportation ainsi que sur la production locale alimentaire. Dans cet article, nous présentons des informations sur le rendement du secteur agricole en prenant en compte ces facteurs externes. Une attention particulière a été accordée a la capacité des micro-exploitations agricoles de s’adapter et de faire face aux les changements externes, en utilisant des connaissances traditionnelles. En outre, il y a des opportunités évidentes pour l’agriculture caribéenne à travers des niches de marchés à l’étranger et des réseaux commerciaux alternatifs, comme le commerce équitable.
Freshwater Resources in the Insular Caribbean: An Environmental Perspective
Authors: Scalley Tamara Heartsill
Published: May 2013

Les îles caribéennes possèdent une grande variété de conditions liées à l’accès aux ressources en eau, y compris celles ayant des rivières asséchées et d’autres disposants de fleuves à naviguer. L’utilisation des ressources en eau douce et potable dans cette région est soumise aux facteurs suivants : 1) les besoins d’une population croissante et ceux de l’industrie agricole intéressée, 2) les exigences d’une économie touristique où la consommation d’eau comprend un usage à des fins de loisirs et esthétiques. Les stratégies de la gestion formelle et informelle de l’eau mises en place dans la région sont basées sur des pratiques individuelles et culturelles de la société et sur des programmes gouvernementaux. Il est important de signaler que plusieurs îles de la région ont déjà une gestion intégrée des ressources hydriques ; cependant, long est le chemin à parcourir en ce qui a trait à une gouvernance sociale de ces ressources et à des investissements solides en termes d’infrastructures vers une meilleure intégration de l’environnement et une gestion adéquate de cette ressource. Dans ce manuscrit nous présentons un résumé sur la description de l’environnement naturel autour de la question de l’eau, des recommandations et des opportunités pour améliorer la gestion des ressources en eau dans la Caraïbe en tenant en compte du contexte environnemental particulier de la région.
Connecting Humans and Ecosystems in Tropical Fisheries: Social Sciences and the Ecosystem-Based Fisheries Management in Puerto Rico and the Caribbean
Authors: Valdés-Pizzini Manuel , García-Quijano Carlos G. , Schärer-Umpierre Michelle T.
Published: May 2013

L’état actuel de l’écosystème caribéen se trouve dans une situation difficile à cause des pressions exercées par la population à travers leur histoire sur son utilisation. La conservation des ressources naturelles nécessite une compréhension des dimensions naturelles et humaines du problème, ainsi qu’une stratégie de recherche et de conservation réconciliant les deux expériences. La gestion de la pêche basée sur l’écosystème (connue par son sigle anglais EBFM) offre une grande opportunité de grandes perspectives pour y arriver parvenir. L’EBFM cherche a vise à protéger la structure et la qualité de l’habitat, en pré-servant l’intégrité et le fonctionnement de l’écosystème, en mettant l’emphase sur la prévention et utilise une approche préventive, et en reconnaissant les limites naturelles et économiques de la pêche en termes d’exploitations piscicoles. Théoriquement, l’EBFM doit opérer dans le cadre du système socio-écologique (une liaison entre le système humain et l’environnement). En dépit de nombreuses discussions, presque rien n’a été fait dans une perspective d’équilibrer les stratégies de l’EFBM et les sciences sociales, car il est difficile de trouver des plans concrets permettant l’intégration des dimensions humaines dans la gestion de la pêche. Cet article traite de l’utilisation actuelle de l’EBFM à Porto Rico ainsi que dans la Caraïbe, et présente une poignée de recommandations visant à favoriser son efficacité.
Not in the Same Boat: Disasters and Differential Vulnerability in the Insular Caribbean
Authors: López-Marrero Tania , Wisner Ben
Published: May 2013

La région caribéenne est exposée à diverses catastrophes naturelles en raison de sa position géographique et sa situation géologique. Ouragans, inondations, glissements de terrains, tremblements de terre et éruptions volcaniques causent des pertes en vies humaines et de biens matériels, perturbent la vie quotidienne et dans certains cas provoquent des années de retards de développement. Cependant, tout comme les risques naturels varient dans la région, les personnes affectées connaissent des peines distinctes. Ces différences reflètent différents facteurs associés a à la vulnérabilité et de la capacité des gens, y compris l’accès aux ressources naturelles, matérielles, économiques, humaines, sociales et politiques. Les différences a l’accès à de telles ressources déterminent comment la population fait face aux risques naturels et gère de façon plus efficace les catastrophes naturelles. Cet article résume les tendances en cas de catastrophes naturelles dans les îles caribéennes et examine ces tendances en tant que facteurs de vulnérabilité et capacité. Il attire aussi l’attention sur les techniques apprises pour réduire la vulnérabilité, et pour améliorer la capacité à gérer les risques. Dans certains cas, il a paru important de repenser les stratégies et les pratiques actuelles de gestions des risques.