bluuebunny/crossref_metadata_2025 huggingface dataset:
Embedded silicon carbide “replicas” patterned by rapid thermal processing of DNA origami on silicon
Authors: Pillers Michelle A. , Lieberman Marya
Published: October 2016

When deoxyribose nucleic acid (DNA) origami on silicon substrates are heated above 900 °C, the carbon atoms from the DNA diffuse several nanometers into the silicon to form embedded silicon carbide (SiC) nanostructures. Atomic force microscopy and scanning electron microscopy images show that the SiC structures retain the shape and lateral dimensions of the original DNA origami structures, and the SiC material resists etching by hydrofluoric acid. X-ray photoelectron spectroscopy depth profiling shows a SiC peak present at depths of up to ∼15 nm. This process is a mask-free technique for patterning SiC on silicon for possible nanoelectronic applications.
Hybrid organic–inorganic perovskite composite fibers produced via melt electrospinning
Authors: Murphy John P. , Ross Brandon M. , Andriolo Jessica M. , Skinner Jack L.
Published: October 2016

A novel fabrication technique for producing hybrid organic–inorganic perovskite impregnated poly(styrene) microfibers in situ in a melt electrospinner is presented. The relationship between the hybrid perovskite precursors, electrospun fiber morphology, and chemical phase domains was investigated using light microscopy, scanning electron microscopy, x-ray diffraction spectroscopy, and energy dispersive spectroscopy. The method was successful in producing composite microfibers and revealed information regarding the nature of encapsulated hybrid perovskites under higher-than-normal temperature conditions during the synthesis and subsequent annealing process.
Derivation of formulas to calculate the saturation correction of ionization chambers in pulsed beams of short, nonvanishing pulse durations
Authors: Karsch Leonhard
Published: October 2016

Purpose

Gas‐filled ionization chambers are the most important radiation detectors in radiotherapy. The collected charge at the electrodes does not represent the total released charge due to the unavoidable recombination processes. This needs to be considered for precise dose measurements. A quantitative description and correction of the recombination effects is established for two cases: continuous radiation exposure and pulsed radiation fields of single pulses with vanishing pulse duration. This work derives formulas for calculating the saturation correction for pulsed beams of nonvanishing pulse duration.

Methods

Recursive formulas are derived describing the spatio‐temporal development of the charge density distributions in plane‐parallel ionization chambers starting at neglected recombination. Pulse duration dependent effective chamber parameters are calculated, by comparing the coefficients of a series expansion for small recombination effects. These parameters are used afterward in the known formula for the saturation correction factor for pulsed irradiation with increased recombination effects which was established with the assumption of vanishing pulse duration.

Results

The formulas should be valid for pulse durations shorter than half the collection time of the chamber. They allow calculating the saturation correction factor for pulsed beams of nonvanishing pulse duration and arbitrary pulse dose, if chamber, beam, and filling gas parameters are known. The filling gas parameters could be determined from experimental data. The calculation results are in good agreement with already published experimental and simulated results for a Roos chamber.

Conclusions

The new formulas can be applied to determine the expected saturation correction for pulsed beams of different pulse duration and pulse dose including new beams at accelerators of new technologies. More experimental validation by using other chambers and an extension of the new formalism to pulse durations longer than half the collection time of the chamber is desired.
Complete elastic constants of α-BaB2O4: Schaefer–Bergmann acousto-optic diffraction and resonant ultrasound spectroscopy
Authors: Pfeiffer Jonathan B. , Wagner Kelvin H. , Kaufman Yaniv , Ledbetter Hassel , Soos Jolanta , Diestler Mark
Published: October 2016

Both Schaefer–Bergmann diffraction and resonant ultrasound spectroscopy were used to measure the six independent elastic-stiffness coefficients of the trigonal, non-piezoelectric crystal α-BaB2O4. The two measurement sets resulted in a root-mean-square variance of 1.2%. This paper provides a detailed analysis of the two different measurement techniques and discusses the similarities and differences.
Climatic warming destabilizes forest ant communities
Authors: Diamond Sarah E. , Nichols Lauren M. , Pelini Shannon L. , Penick Clint A. , Barber Grace W. , Cahan Sara Helms , Dunn Robert R. , Ellison Aaron M. , Sanders Nathan J. , Gotelli Nicholas J.
Published: October 2016

A field-based climate warming experiment reveals a loss of dynamical community stability due to altered species interactions.
A disynaptic feedback network activated by experience promotes the integration of new granule cells
Authors: Alvarez Diego D. , Giacomini Damiana , Yang Sung Min , Trinchero Mariela F. , Temprana Silvio G. , Büttner Karina A. , Beltramone Natalia , Schinder Alejandro F.
Published: October 2016

Integration of adult-born brain cells

Physical exercise or exploration of a novel environment greatly influences the production, maturation, and connectivity of adult-born neurons. Alvarez
et al.
investigated how experience affects the incorporation of adult-born neurons into the hippocampal network. A brief period of sensory enrichment when new neurons were 9 to 10 days old led to neurons having larger dendrites and more functional spine synapses. A disynaptic preexisting feedback circuit promoted the growth and integration of the new cells.

Science
, this issue p.
459
Systems-level analysis of mechanisms regulating yeast metabolic flux
Authors: Hackett Sean R. , Zanotelli Vito R. T. , Xu Wenxin , Goya Jonathan , Park Junyoung O. , Perlman David H. , Gibney Patrick A. , Botstein David , Storey John D. , Rabinowitz Joshua D.
Published: October 2016

Quantitation of metabolic pathway regulation

Although metabolic biochemical pathways are well understood, less is known about precisely how reaction rates or fluxes through the various enzymes are controlled. Hackettet al.developed a method to quantitate such regulatory influence in yeast. They monitored concentrations of metabolites, enzymes, and potential regulators by LC-MS/MS (liquid chromatography–tandem mass spectrometry) and isotope ratio measurements for 56 reactions, over 100 metabolites, and 370 metabolic enzymes in yeast in 25 different steady-state conditions. Bayesian analysis was used to examine the probability of regulatory interactions. Regulation of flux through the pathways was predominantly controlled by changes in the concentration of small-molecule metabolites rather than changes in enzyme abundance. The analysis also revealed previously unrecognized regulation between pathways.

Science, this issue p.432
Increased spatiotemporal resolution reveals highly dynamic dense tubular matrices in the peripheral ER
Authors: Nixon-Abell Jonathon , Obara Christopher J. , Weigel Aubrey V. , Li Dong , Legant Wesley R. , Xu C. Shan , Pasolli H. Amalia , Harvey Kirsten , Hess Harald F. , Betzig Eric , Blackstone Craig , Lippincott-Schwartz Jennifer
Published: October 2016

A dynamic view of the endoplasmic reticulum

The endoplasmic reticulum (ER) is a complex membranous structure that extends from the nuclear envelope to the cell periphery. It has important roles in many cellular processes, and numerous proteins are involved in maintaining its structure. Nixon-Abell
et al.
used superresolution approaches to look at the ER at the periphery of the cell, where the ER contacts many other cellular organelles (see the Perspective by Terasaki). This peripheral ER has been thought to comprise tubules and sheets; however, the higher-resolution view revealed that most of the “sheets” consist of a dense clustering of tubules. This dynamic meshwork may allow the ER to change its conformation rapidly in response to cellular needs.

Science
, this issue p.
433
; see also p.
415
Senescent intimal foam cells are deleterious at all stages of atherosclerosis
Authors: Childs Bennett G. , Baker Darren J. , Wijshake Tobias , Conover Cheryl A. , Campisi Judith , van Deursen Jan M.
Published: October 2016

Wreaking havoc while (growth-)arrested

Cells enter a state of senescence in response to certain stresses. Studying mouse models, Childs
et al.
examined the role of senescent lipid-loaded macrophages (so-called “foam cells”) in the pathogenesis of atherosclerosis. At early stages of atherosclerosis, senescent foam cells promoted the expression of inflammatory cytokines. At later stages, they promoted the expression of matrix metalloproteases implicated in the rupture of atherosclerotic plaque, which can lead to blood clots. Experimental removal of the senescent cells had beneficial effects at both stages of the disease.

Science
, this issue p.
472
Formation of the Orientale lunar multiring basin
Authors: Johnson Brandon C. , Blair David M. , Collins Gareth S. , Melosh H. Jay , Freed Andrew M. , Taylor G. Jeffrey , Head James W. , Wieczorek Mark A. , Andrews-Hanna Jeffrey C. , Nimmo Francis , Keane James T. , Miljković Katarina , Soderblom Jason M. , Zuber Maria T.
Published: October 2016

titOn the origin of Orientale basinle

Orientale basin is a major impact crater on the Moon, which is hard to see from Earth because it is right on the western edge of the lunar nearside. Relatively undisturbed by later events, Orientale serves as a prototype for understanding large impact craters throughout the solar system. Zuber
et al.
used the Gravity Recovery and Interior Laboratory (GRAIL) mission to map the gravitational field around the crater in great detail by flying the twin spacecraft as little as 2 km above the surface. Johnson
et al.
performed a sophisticated computer simulation of the impact and its subsequent evolution, designed to match the data from GRAIL. Together, these studies reveal how major impacts affect the lunar surface and will aid our understanding of other impacts on rocky planets and moons.

Science
, this issue pp.
438
and
441
Versatile cluster entangled light
Authors: Briegel Hans J.
Published: October 2016

Dark excitons are used to entangle strings of hundreds of photons for quantum information processing
Rapid Metagenomic Next-Generation Sequencing during an Investigation of Hospital-Acquired Human Parainfluenza Virus 3 Infections
Authors: Greninger Alexander L. , Zerr Danielle M. , Qin Xuan , Adler Amanda L. , Sampoleo Reigran , Kuypers Jane M. , Englund Janet A. , Jerome Keith R.
Published: October 2016

Metagenomic next-generation sequencing (mNGS) is increasingly used for the unbiased detection of viruses, bacteria, fungi, and eukaryotic parasites in clinical samples. Whole-genome sequencing (WGS) of clinical bacterial isolates has been shown to inform hospital infection prevention practices, but this technology has not been utilized during potential respiratory virus outbreaks. Here, we report on the use of mNGS to inform the real-time infection prevention response to a cluster of hospital-acquired human parainfluenza 3 virus (HPIV3) infections at a children's hospital. Samples from 3 patients with hospital-acquired HPIV3 identified over a 12-day period on a general medical unit and 10 temporally associated samples from patients with community-acquired HPIV3 were analyzed. Our sample-to-sequencer time was <24 h, while our sample-to-answer turnaround time was <60 h with a hands-on time of approximately 6 h. Eight (2 cases and 6 controls) of 13 samples had sufficient sequencing coverage to yield the whole genome for HPIV3, while 10 (2 cases and 8 controls) of 13 samples gave partial genomes and all 13 samples had >1 read for HPIV3. Phylogenetic clustering revealed the presence of identical HPIV3 genomic sequence in the two of the cases with hospital-acquired infection, consistent with the concern for recent transmission within the medical unit. Adequate sequence coverage was not recovered for the third case. This work demonstrates the promise of mNGS for providing rapid information for infection prevention in addition to microbial detection.
Development of a Sensitive and Specific Serological Assay Based on Luminex Technology for Detection of Antibodies to Zaire Ebola Virus
Authors: Ayouba Ahidjo , Touré Abdoulaye , Butel Christelle , Keita Alpha Kabinet , Binetruy Florian , Sow Mamadou S. , Foulongne Vincent , Delaporte Eric , Peeters Martine
Published: October 2016

The recent Zaire Ebola virus (EBOV) outbreak in West Africa illustrates clearly the need for additional studies with humans and animals to elucidate the ecology of Ebola viruses (EBVs). In this study, we developed a serological assay based on the Luminex technology. Nine recombinant proteins representing different viral regions (nucleoprotein [NP], 40-kDa viral protein [VP40], and glycoprotein [GP]) from four of the five EBV lineages were used. Samples from 94 survivors of the EBOV outbreak in Guinea and negative samples from 108 patients in France were used to calculate test performance for EBOV detection and cross-reaction with other Ebola virus lineages. For EBOV antibody detection, sensitivities of 95.7%, 96.8%, and 92.5% and specificities of 94.4%, 95.4%, and 96.3% for NP, GP, and VP40, respectively, were observed. All EBOV-negative samples that presented a reaction, except for one, interacted with a single antigen, whereas almost all samples from EBOV survivors were simultaneously reactive with NP and GP (90/94) or with NP, GP, and VP40 (87/94). Considering as positive for past EBOV infection only samples that reacted with EBOV NP and GP, sensitivity was 95.7% and specificity increased to 99.1%. Comparing results with commercial EBOV NP and GP enzyme-linked immunosorbent assays (ELISAs; Alpha Diagnostic, San Antonio, TX), lower sensitivity (92.5%) and high specificity (100%) were observed with the same positivity criteria. Samples from EBOV survivors cross-reacted with GP from Sudan Ebola virus (GP-SUDV) (81.9%), GP from Bundibugyo Ebola virus (GP-BDBV) (51.1%), GP from Reston Ebola virus (GP-RESTV) (9.6%), VP40-SUDV (76.6%), and VP40-BDBV (38.3%). Overall, we developed a sensitive and specific high-throughput serological assay, and defined an algorithm, for epidemiological surveys with humans.
Dual Roles of the Hemagglutinin Segment-Specific Noncoding Nucleotides in the Extended Duplex Region of the Influenza A Virus RNA Promoter
Authors: Wang Jingfeng , Li Jinghua , Zhao Lili , Cao Mengmeng , Deng Tao
Published: October 2016

We recently reported that the segment-specific noncoding regions (NCRs) of the hemagglutinin (HA) and neuraminidase (NA) segments are subtype specific, varying significantly in sequence and length at both the 3′ and 5′ ends. Interestingly, we found that nucleotides CC at positions 13 and 14 at the 3′ end and GUG at positions 14 to 16 at the 5′ end (termed 14′ and 16′ to distinguish them from 3′ positions) are absolutely conserved among all HA subtype-specific NCRs. These HA segment-specific NCR nucleotides are located in the extended duplex region of the viral RNA promoter. In order to understand the significance of these highly conserved HA segment-specific NCR nucleotides in the virus life cycle, we performed extensive mutagenesis on the HA segment-specific NCR nucleotides and studied their functional significance in regulating influenza A virus replication in the context of the HA segment with both RNP reconstitution and virus infection systems. We found that the base pairing of the 3′-end 13 position with the 5′-end 14′ position (
3′
13-
5′
14′) position is critical for RNA promoter activity while the identity of the base pair is critical in determining HA segment packaging. Moreover, the identity of the residue at the 3′-end 14 position is functionally more important in regulating virus genome packaging than in regulating viral RNA synthesis. Taken together, these results demonstrated that the HA segment-specific NCR nucleotides in the extended duplex region of the promoter not only form part of the promoter but also play a key role in controlling virus selective genome packaging.

IMPORTANCE
The segment-specific complementary nucleotides (13 to 15 in the 3′ end and 14′ to 16′ in the 5′ end) in the extended duplex region of the influenza virus RNA promoter vary significantly among different segments and have rarely been studied. Here, we performed mutagenesis analysis of the highly conserved HA segment-specific nucleotides in the extended duplex region and examined their effects on virus replication in the context of the influenza A/WSN/33 (WSN) virus infection. We found that these HA segment-specific nucleotides not only act as a part of the RNA promoter but also play a critical role in HA segment packaging. Therefore, we showed experimentally, for the first time, the requirement of the nucleotides in the extended duplex region for the RNA promoter and also identified specific noncoding residues in regulating HA segment packaging. This work has implications for the development of attenuated vaccine strains and for elucidation the mechanisms of the virus genome packaging.
Evolution of
Mycobacterium tuberculosis
: New Insights into Pathogenicity and Drug Resistance
Authors: Boritsch Eva C. , Brosch Roland
Published: October 2016

The tuberculosis agent
Mycobacterium tuberculosis
has undergone a long and selective evolution toward human infection and represents one of the most widely spread pathogens due to its efficient aerosol-mediated human-to-human transmission. With the availability of more and more genome sequences, the evolutionary trajectory of this obligate pathogen becomes visible, which provides us with new insights into the molecular events governing evolution of the bacterium and its ability to accumulate drug-resistance mutations. In this review, we summarize recent developments in mycobacterial research related to this matter that are important for a better understanding of the current situation and future trends and developments in the global epidemiology of tuberculosis, as well as for possible public health intervention possibilities.
Phenotypic Screens Identify Parasite Genetic Factors Associated with Malarial Fever Response in Plasmodium falciparum
piggyBac
Mutants
Authors: Thomas Phaedra , Sedillo Jennifer , Oberstaller Jenna , Li Suzanne , Zhang Min , Singh Naresh , Wang Chengqi C. Q. , Udenze Kenneth , Jiang Rays H. Y. , Adams John H.
Published: October 2016

Though the
P. falciparum
genome sequence has been available for many years, ~40% of its genes do not have informative annotations, as they show no detectable homology to those of studied organisms. More still have not been evaluated via genetic methods. Scalable forward-genetic approaches that allow interrogation of gene function without any pre-existing knowledge are needed to hasten understanding of parasite biology, which will expedite the identification of drug targets and the development of future interventions in the face of spreading resistance to existing frontline drugs. In this work, we describe a new approach to pursue forward-genetic phenotypic screens for
P. falciparum
to identify factors associated with virulence. Future large-scale phenotypic screens developed to probe other such interesting phenomena, when considered in parallel, will prove a powerful tool for functional annotation of the
P. falciparum
genome, where so much remains undiscovered.
Bilateral necrotising sialometaplasia
Authors: Kandula Srinivas , Manjunatha Bhari Sharanesha , Tayee Priyanka , Astekar Madhusudan
Published: October 2016

Necrotising sialometaplasia is a benign, necrotising, self-healing inflammatory condition categorised as idiopathic disease of salivary glands. This condition holds diagnostic importance because of its clinical and histopathological presentation, which is ambiguous, and can be misdiagnosed as carcinoma particularly squamous cell carcinoma or mucoepidermoid carcinoma. This report describes a case of bilateral necrotising sialometaplasia occurring in a 38-year-old male patient.
Reversal of anticoagulation with four-factor prothrombin complex concentrate without concurrent vitamin K (phytonadione) for urgent surgery in a patient at moderate-to-high risk for thromboembolism
Authors: Farley Thomas Michael , Andreas Elisha M
Published: October 2016

Successful vitamin K antagonist (eg, warfarin) reversal with 4-factor prothrombin complex concentrate (4F-PCC) without vitamin K (phytonadione) for emergent surgery in a patient at moderate-to-high risk for thromboembolism is reported. This approach may decrease the risk for development of thrombus, as it limits the amount of time the patient's anticoagulation is subtherapeutic. It also may increase the risk of bleeding, so patient selection is essential if this strategy is employed. Caution must be exercised to complete the procedure or surgery in the window of peak 4F-PCC effect (∼1–6 hours postinfusion).
Lower limb immobilisation and venous thromboembolism risk: combined case–control studies
Authors: Braithwaite Irene , Healy Bridget , Cameron Laird , Weatherall Mark , Beasley Richard
Published: October 2016

Background

Evidence from randomised controlled trials shows that low-molecular-weight heparin is effective in reducing the risk of venous thromboembolism (VTE) in the clinical setting of temporary lower limb immobilisation. Despite this, international guidelines are non-committal in advocating the use of anticoagulation in this clinical scenario. We determined the risk of VTE associated with lower limb immobilisation and the proportion of VTE events associated with lower limb immobilisation by undertaking a secondary analysis of two case–control studies that had used a similar methodology.

Methods

We undertook logistic regression analysis to investigate the association of risk factors with VTE with the OR and 95% CIs for association between lower limb immobilisation and VTE the primary outcome variable. The proportion of VTE patients with lower limb immobilisation was also calculated.

Results

Cases comprised 396 patients aged 18–65 years with radiologically confirmed deep vein thrombosis or pulmonary embolism attending outpatient VTE clinics. Controls, also aged 18–65 years, comprised 197 inpatients in the coronary care unit and 200 outpatients treated for upper limb injuries in the fracture clinic. The OR for association between VTE and lower limb immobilisation was 73.1 (95% CI 10.1 to 530, p<0.001). In 62/396 (16%) cases, patients had undergone lower limb immobilisation within four weeks of their presentation with VTE, representing the most common potentially preventable cause of VTE in this sample.

Conclusions

Lower limb immobilisation is associated with a markedly increased risk of VTE and represents the most common potentially preventable cause in the 18–65-year age group, being present in one in seven cases treated for VTE. Consideration should be given to pharmacological prophylaxis in patients with lower limb immobilisation to reduce the substantial burden of preventable VTE.
Impacts of human hunting on spatial behavior of white-tailed deer (Odocoileus virginianus)
Authors: Marantz Sierra A. , Long Jed A. , Webb Stephen L. , Gee Kenneth L. , Little Andrew R. , Demarais Stephen
Published: October 2016

Predators can influence populations through top-down effects, but most large predators have been extirpated from the range of white-tailed deer (Odocoileus virginianus (Zimmermann, 1780)). Hunters have filled this predatory role, but also can indirectly influence prey species. Indirect behavioral responses can include altered resource selection, space use, or movement. Herein, we developed a controlled study that contained both temporal and spatial risk levels to assess how deer behavior changes relative to temporal periods of risk. Total distance travelled and microrange area over 2-day periods were used to determine the general effects of hunting season on deer spatial behavior. Generally, distance travelled, microrange area, and exploratory behavior decreased during the course of the study, with the greatest decrease occurring during the active 16-day hunting period. Despite potential risk and disturbance from hunters, deer maintained site fidelity to previously established ranges and did not expand microrange areas. These data indicate that deer recognize threats from humans on the landscape and adapt behavioral strategies by minimizing movement and exhibiting high residency times in well-established ranges, factors known to influence harvest susceptibility. This information can be used to assess potential impacts from hunting for management purposes, but also to test the adaptive ability of animals to risk.
A fundamental dichotomy in long-chain polyunsaturated fatty acid abundance between and within marine and terrestrial ecosystems
Authors: Colombo Stefanie M. , Wacker Alexander , Parrish Christopher C. , Kainz Martin J. , Arts Michael T.
Published: October 2016

Polyunsaturated fatty acids (PUFA), especially long-chain (i.e., ≥20 carbons) polyunsaturated fatty acids (LC-PUFA), are fundamental to the health and survival of marine and terrestrial organisms. Therefore, it is imperative that we gain a better understanding of their origin, abundance, and transfer between and within these ecosystems. We evaluated the natural variation in PUFA distribution and abundance that exists between and within these ecosystems by amassing and analyzing, using multivariate and analysis of variance (ANOVA) methods, >3000 fatty acid (FA) profiles from marine and terrestrial organisms. There was a clear dichotomy in LC-PUFA abundance between organisms in marine and terrestrial ecosystems, mainly driven by the C18PUFA in terrestrial organisms and omega-3 (n-3) LC-PUFA in marine organisms. The PUFA content of an organism depended on both its biome (marine vs terrestrial) and taxonomic group. Within the marine biome, the PUFA content varied among taxonomic groups. PUFA content of marine organisms was dependent on both geographic zone (i.e., latitude, and thus broadly related to temperature) and trophic level (a function of diet). The contents of n-3 LC-PUFA were higher in polar and temperate marine organisms than those from the tropics. Therefore, we conclude that, on a per capita basis, high latitude marine organisms provide a disproportionately large global share of these essential nutrients to consumers, including terrestrial predators. Our analysis also hints at how climate change, and other anthropogenic stressors, might act to negatively impact the global distribution and abundance of n-3 LC-PUFA within marine ecosystems and on the terrestrial consumers that depend on these subsidies.
Vasorelaxant Action of the Chloroform Fraction of Orthosiphon stamineus via NO/cGMP Pathway, Potassium and Calcium Channels
Authors: Yam Mun Fei , Tan Chu Shan , Ahmad Mariam , Ruan Shibao
Published: October 2016

Orthosiphon stamineus Benth. (Lamiaceae) is an important plant in traditional folk medicine that is used to treat hypertension and kidney stones. In humans, this plant has been tested as an addition regiment for antihypertensive treatment. Among the treatments for hypertension, O. stamineus had been to have diuretic and vasorelaxant effects in animal models. There is still very little information regarding the vasorelaxant effect of O. stamineus. Therefore, the present study was designed to investigate the vasorelaxant activity and mechanism of action of the fractions of O. stamineus. The vasorelaxant activity and the underlying mechanisms of the chloroform fraction of the 50% methanolic extract of O. stamineus (CF) was evaluated on thoracic aortic rings isolated from Sprague Dawley rats. CF caused relaxation of the aortic ring pre-contracted with phenylephrine in the presence and absence of endothelium, and pre-contracted with potassium chloride in endothelium-intact aortic ring. In the presence of endothelium, both indomethacin (a nonselective cyclooxygenase inhibitor) and [Formula: see text]-[1,2,4]Oxadiazolo[4,3-[Formula: see text]]quinoxalin-1-one (ODQ, selective soluble guanylate cyclase inhibitor) had a small effect on the vasorelaxation response. On the other hand, in the presence of Nω-nitro-L-arginine methyl ester (L-NAME, nitric oxide synthase inhibitor), methylene blue (cyclic guanosine monophosphate lowering agent), tetraethylammonium ([Formula: see text], nonselective calcium activator [Formula: see text] channel blocker), 4-aminopyridine (4-AP, voltage-dependent [Formula: see text] channel blocker), barium chloride ([Formula: see text], inwardly rectifying [Formula: see text] channel blocker), glibenclamide (nonspecific ATP-sensitive [Formula: see text] channel blocker), atropine (muscarinic receptor blocker) and propranolol (β-adrenergic receptor blocker), the vasorelaxant effect significantly reduced the relaxation stimulated by CF. CF was also found to be active in reducing [Formula: see text] release from the sarcoplasmic reticulum and blocking calcium channels.
An Efficient System for Heart Disease Prediction Using Hybrid OFBAT with Rule-Based Fuzzy Logic Model
Authors: Reddy G. Thippa , Khare Neelu
Published: October 2016

The objective of the work is to predict heart disease using computing techniques like an oppositional firefly with BAT and rule-based fuzzy logic (RBFL). The system would help the doctors to automate heart disease diagnosis and to enhance the medical care. In this paper, a hybrid OFBAT-RBFL heart disease diagnosis system is designed. Here, at first, the relevant features are selected from the dataset using locality preserving projection (LPP) algorithm which helps the diagnosis system to develop a classification model using the fuzzy logic system. After that, the rules for the fuzzy system are created from the sample data. Among the entire rules, the important and relevant group of rules are selected using OFBAT algorithm. Here, the opposition based learning (OBL) is hybrid to the firefly with BAT algorithm to improve the performance of the FAT algorithm while optimizing the rules of the fuzzy logic system. Next, the fuzzy system is designed with the help of designed fuzzy rules and membership functions so that classification can be carried out within the fuzzy system designed. At last, the experimentation is performed by means of publicly available UCI datasets, i.e., Cleveland, Hungarian and Switzerland datasets. The experimentation result proves that the RBFL prediction algorithm outperformed the existing approach by attaining the accuracy of 78%.
Complex Nonlinear Dynamic System of Oligopolies Price Game with Heterogeneous Players Under Noise
Authors: Liu Feng , Li Yaguang
Published: October 2016

A nonlinear four oligopolies price game with heterogeneous players, that are boundedly rational and adaptive, is built using two different special demand costs. Based on the theory of complex discrete dynamical system, the stability and the existing equilibrium point are investigated. The complex dynamic behavior is presented via bifurcation diagrams, the Lyapunov exponents to show equilibrium state, bifurcation and chaos with the variation in parameters. As disturbance is ubiquitous in economic systems, this paper focuses on the analysis of delay feedback control method under noise circumstances. Stable dynamics is confirmed to depend mainly on the low price adjustment speed, and if all four players have limited opportunities to stabilize the market, the new adaptive player facing profits of scale are found to be higher than the incumbents of bounded rational.
Bifurcation Analysis of Planar Piecewise Linear System with Different Dynamics
Authors: Guo Xiaoshi , Pi Dingheng , Gao Zhensheng
Published: October 2016

In this paper, we investigate the bifurcation phenomena of a planar piecewise linear system. This piecewise linear system comprises two linear subsystems. The two linear subsystems have different types of dynamics. One subsystem has node or saddle dynamic and the other has focus dynamic. Some sufficient and necessary conditions for the existence of periodic orbit are given by studying the properties of Poincaré maps. Our results show that two crossing periodic orbits can bifurcate from this piecewise linear system. Moreover, we establish some sufficient and necessary conditions for the existence of sliding periodic orbit, crossing–sliding periodic orbit and sliding homoclinic orbit passing through a pseudo saddle and so on. We find that this piecewise system can appear multiply as two limit cycle bifurcation, buckling bifurcation, critical crossing cycle bifurcation, sliding homoclinic bifurcation, pseudo homoclinic bifurcation and so on. To our knowledge, sliding bifurcation phenomena are usually ignored when people study piecewise linear systems.
Epileptic Seizure Prediction Using a New Similarity Index for Chaotic Signals
Authors: Niknazar Hamid , Nasrabadi Ali Motie
Published: October 2016

Epileptic seizures are generated by abnormal activity of neurons. The prediction of epileptic seizures is an important issue in the field of neurology, since it may improve the quality of life of patients suffering from drug resistant epilepsy. In this study a new similarity index based on symbolic dynamic techniques which can be used for extracting behavior of chaotic time series is presented. Using Freiburg EEG dataset, it is found that the method is able to detect the behavioral changes of the neural activity prior to epileptic seizures, so it can be used for prediction of epileptic seizure. A sensitivity of 63.75% with 0.33 false positive rate (FPR) in all 21 patients and sensitivity of 96.66% with 0.33 FPR in eight patients were achieved using the proposed method. Moreover, the method was evaluated by applying on Logistic and Tent map with different parameters to demonstrate its robustness and ability in determining similarity between two time series with the same chaotic characterization.
Stability and Hopf Bifurcation Analysis in Hindmarsh–Rose Neuron Model with Multiple Time Delays
Authors: Hu Dongpo , Cao Hongjun
Published: October 2016

In this paper, the dynamical behaviors of a single Hindmarsh–Rose neuron model with multiple time delays are investigated. By linearizing the system at equilibria and analyzing the associated characteristic equation, the conditions for local stability and the existence of local Hopf bifurcation are obtained. To discuss the properties of Hopf bifurcation, we derive explicit formulas to determine the direction of Hopf bifurcation and the stability of bifurcated periodic solutions occurring through Hopf bifurcation. The qualitative analyses have demonstrated that the values of multiple time delays can affect the stability of equilibrium and play an important role in determining the properties of Hopf bifurcation. Some numerical simulations are given for confirming the qualitative results. Numerical simulations on the effect of delays show that the delays have different scales when the two delay values are not equal. The physiological basis is most likely that Hindmarsh–Rose neuron model has two different time scales. Finally, the bifurcation diagrams of inter-spike intervals of the single Hindmarsh–Rose neuron model are presented. These bifurcation diagrams show the existence of complex bifurcation structures and further indicate that the multiple time delays are very important parameters in determining the dynamical behaviors of the single neuron. Therefore, these results in this paper could be helpful for further understanding the role of multiple time delays in the information transmission and processing of a single neuron.
Devaney Chaos in Nonautonomous Discrete Systems
Authors: Zhu Hao , Shi Yuming , Shao Hua
Published: October 2016

This paper is concerned with Devaney chaos in nonautonomous discrete systems. It is shown that in its definition, the two former conditions, i.e. transitivity and density of periodic points, in a set imply the last one, i.e. sensitivity, in the case that the set is unbounded, while a similar result holds under two additional conditions in the other case that the set is bounded. Some chaotic behavior is studied for a class of nonautonomous discrete systems, each of which is governed by a convergent sequence of continuous maps. In addition, the concepts of some pseudo-orbits and shadowing properties are introduced for nonautonomous discrete systems, and it is shown that some shadowing properties of the system and density of periodic points imply that the system is Devaney chaotic under the condition that the sequence of continuous maps is uniformly convergent in a compact metric space.
Analysis of Policy-Based Systems with AGILE Policies Using Petri Nets
Authors: Pelc Mariusz
Published: October 2016

Autonomic and self-* systems of all kinds are expected to operate in a stable and predictable way. This in a natural way implies the need for pre-deployment design-time verification of the decision making logic, meant by a process of proving that the logic deployed into the autonomic service/software component meets all requirements and will not lead to any unpredicted or unwanted behavior. There is actually no simple way that can be used for verification of the decision making logic used self-* and autonomic systems as only methods that use some kind of formalism can in an objective way verify the logic correctness. There is one problem, however, with this kind of approach — the formalism may vary depending on the way the decision making logic is expressed (for example, it may be in the form of a policy).

In this paper, an approach to verification of policy decision making logic is based on its transformation into the corresponding Petri net using the proposed methodology. Consequently, the resulting Petri net can then be verified using Petri nets formalism and these verification results can be used to assess policy correctness. Two policies were used to illustrate the approach: ACSPolicy controlling the basic operation of an Air Conditioning System (ACS) in a car and ACSFullPolicy being its more sophisticated version allowing the controlled ACS to work in three pre-defined modes. The second policy shows how easily the proposed methodology scales up allowing the analysis policies of any complexity level.
Design of the Tableau Reasoner TGC2 for Description Logics
Authors: Nguyen Linh Anh
Published: October 2016

Ontologies have been applied in a wide range of practical domains. They play a key role in data modeling, information integration, and the creation of semantic web services, intelligent web sites and intelligent software agents. The Web ontology language OWL, recommended by W3C, is based on description logics (DLs). Automated reasoning in DLs is very important for the success of OWL, as it provides support for visualization, debugging, and querying of ontologies. The existing ontology reasoners are not yet satisfactory, especially when dealing with qualified number restrictions and large ontologies. In this paper, we present the design of our new reasoner TGC2, which uses tableaux with global caching for reasoning in E xpTime-complete DLs. The characteristic of TGC2 is that it is based on our tableau methods with the optimal ( ExpTime) complexity, while the existing well-known tableau-based reasoners for DLs have a non-optimal complexity (at least NExpTime). We briefly describe the tableau methods used by TGC2. We then provide the design principles of TGC2 and some important optimization techniques for increasing the efficiency of this reasoner. We also present preliminary evaluation results of TGC2. They show that TGC2 deals with qualified number restrictions much better than the other existing reasoners.
Subglacial water escape structures and shearing; a case study of hidden problems for construction below rockhead in glaciated regions
Authors: Cowsill P. A. , de Freitas M. H. , van der Meer J. J. M.
Published: October 2016

Two shafts constructed on the floodplain of the River Ribble in Preston as part of an improvement of urban drainage were excavated through the sands and gravels of the Ribble alluvium overlying sands and gravels of glaciofluvial origin, which covered sandstones of the Sherwood Sandstone Group. Water level was close to ground level. Pumping tests had shown that the hydraulic connection between the drift and the sandstone was poor, thus the design concept for both shafts was to cut off groundwater in the permeable drift with diaphragm walls socketed into the sandstones where groundwater flow was considered controllable by pumping from within the shafts. Despite this, the excavation of both shafts was interrupted by inflows of groundwater carrying sand, so they had to be flooded to protect the stability of the excavation. The problems occurred when the base of each shaft was above the base of their respective diaphragm walls. At the time the inflows appeared to be the result of piping from groundwater that had penetrated through the superficial deposits and the sandstone, on the outside of the diaphragm wall. It was concluded that hydraulic connections of high conductivity existed that permitted groundwater to move from the drift to the bedrock. To recover the shafts jet grouting was used around the outside of the shafts to intercept any such connections. This was backed up with dewatering wells and the shafts were completed successfully. Detailed investigations to establish the cause for the groundwater flows were undertaken in parallel with shaft recovery. These forensic investigations confirmed the integrity of the diaphragm walls, and revealed evidence of glacial shearing and water escape structures within the sandstone. Such features could explain the groundwater inflows encountered if they provided high-conductivity connections to groundwater in the overlying superficial deposits. This case study describes the difficulty in finding these geotechnical hazards during a ground investigation. It is likely that they are more commonly associated with glacial processes than is currently recognized. The study illustrates how easy it is for these features to be overlooked by conventional ground investigation.
Hydrogen sulfide, an enhancer of vascular nitric oxide signaling: mechanisms and implications
Authors: Szabo Csaba
Published: October 2016

Nitric oxide (NO) vascular signaling has long been considered an independent, self-sufficient pathway. However, recent data indicate that the novel gaseous mediator, hydrogen sulfide (H2S), serves as an essential enhancer of vascular NO signaling. The current article overviews the multiple levels at which this enhancement takes place. The first level of interaction relates to the formation of biologically active hybrid S/N species and the H2S-induced stimulation of NO release from its various stable “pools” (e.g., nitrite). The next interactions occur on the level of endothelial calcium mobilization and PI3K/Akt signaling, increasing the specific activity of endothelial NO synthase (eNOS). The next level of interaction occurs on eNOS itself; H2S directly interacts with the enzyme: sulfhydration of critical cysteines stabilizes it in its physiological, dimeric state, thereby optimizing eNOS-derived NO production and minimizing superoxide formation. Yet another level of interaction, further downstream, occurs at the level of soluble guanylate cyclase (sGC): H2S stabilizes sGC in its NO-responsive, physiological, reduced form. Further downstream, H2S inhibits the vascular cGMP phosphodiesterase (PDE5), thereby prolonging the biological half-life of cGMP. Finally, H2S-derived polysulfides directly activate cGMP-dependent protein kinase (PKG). Taken together, H2S emerges an essential endogenous enhancer of vascular NO signaling, contributing to vasorelaxation and angiogenesis. The functional importance of the H2S/NO cooperative interactions is highlighted by the fact that H2S loses many of its beneficial cardiovascular effects when eNOS is inactive.
Relationship between gastric motility and liquid mixing in the stomach
Authors: Miyagawa Taimei , Imai Yohsuke , Ishida Shunichi , Ishikawa Takuji
Published: October 2016

The relationship between gastric motility and the mixing of liquid food in the stomach was investigated with a numerical analysis. Three parameters of gastric motility were considered: the propagation velocity, frequency, and terminal acceleration of peristaltic contractions. We simulated gastric flow with an anatomically realistic geometric model of the stomach, considering free surface flow and moving boundaries. When a peristaltic contraction approaches the pylorus, retropulsive flow is generated in the antrum. Flow separation then occurs behind the contraction. The extent of flow separation depends on the Reynolds number (Re), which quantifies the inertial forces due to the peristaltic contractions relative to the viscous forces of the gastric contents; no separation is observed at low Re, while an increase in reattachment length is observed at high Re. While mixing efficiency is nearly constant for low Re, it increases with Re for high Re because of flow separation. Hence, the effect of the propagation velocity, frequency, or terminal acceleration of peristaltic contractions on mixing efficiency increases with Re.
Relationship between oxidative stress and brain swelling in goldfish (Carassius auratus) exposed to high environmental ammonia
Authors: Lisser David F. J. , Lister Zachary M. , Pham-Ho Phillip Q. H. , Scott Graham R. , Wilkie Michael P.
Published: October 2016

Buildups of ammonia can cause potentially fatal brain swelling in mammals, but such swelling is reversible in the anoxia- and ammonia-tolerant goldfish ( Carassius auratus). We investigated brain swelling and its possible relationship to oxidative stress in the brain and liver of goldfish acutely exposed to high external ammonia (HEA; 5 mmol/l NH4Cl) at two different acclimation temperatures (14°C, 4°C). Exposure to HEA at 14°C for 72h resulted in increased internal ammonia and glutamine concentrations in the brain, and it caused cellular oxidative damage in the brain and liver. However, oxidative damage was most pronounced in brain, in which there was a twofold increase in thiobarbituric acid–reactive substances, a threefold increase in protein carbonylation, and a 20% increase in water volume (indicative of brain swelling). Increased activities of catalase, glutathione peroxidase, and glutathione reductase in the brain suggested that goldfish upregulate their antioxidant capacity to partially offset oxidative stress during hyperammonemia at 14°C. Notably, acclimation to colder (4°C) water completely attenuated the oxidative stress response to HEA in both tissues, and there was no change in brain water volume despite similar increases in internal ammonia. We suggest that ammonia-induced oxidative stress may be responsible for the swelling of goldfish brain during HEA, but further studies are needed to establish a mechanistic link between reactive oxygen species production and brain swelling. Nevertheless, a high capacity to withstand oxidative stress in response to variations in internal ammonia likely explains why goldfish are more resilient to this stressor than most other vertebrates.