bluuebunny/crossref_metadata_2025 huggingface dataset:
The role of sentinel lymph node mapping in small animal veterinary medicine: A comparison with current approaches in human medicine
Authors: Beer P. , Pozzi A. , Rohrer Bley C. , Bacon N. , Pfammatter N. S. , Venzin C.
Published: November 2017

The relevance of regional lymph node (LN) assessment to quantify the metastatic spread of cancer is well recognized in veterinary oncology. Evaluation of LNs is critical for tumour staging. However, sampling the correct LN may not be possible without sentinel lymph node (SLN) mapping. Methods for diagnostic imaging and intraoperative detection of SLNs are well established in human medicine, in particular, the combination of lymphoscintigraphy and intraoperative application of blue dyes. Nevertheless, alternative imaging techniques are available and have gained increasing interest. Successful implementation of these techniques in dogs have been reported in both clinical and experimental studies. This review aims to provide an overview of SLN mapping techniques in human and veterinary medicine.
Hyperexcitability of the network contributes to synchronization processes in the human epileptic neocortex
Authors: Tóth Kinga , Hofer Katharina T. , Kandrács Ágnes , Entz László , Bagó Attila , Erőss Loránd , Jordán Zsófia , Nagy Gábor , Sólyom András , Fabó Dániel , Ulbert István , Wittner Lucia
Published: November 2017

Key points

Hyperexcitability and hypersynchrony of neuronal networks are thought to be linked to the generation of epileptic activity in both humans and animal models.

Here we show that human epileptic postoperative neocortical tissue is able to generate two different types of synchronies in vitro.

Epileptiform bursts occurred only in slices derived from epileptic patients and were hypersynchronous events characterized by high levels of excitability.

Spontaneous population activity emerged in both epileptic and non‐epileptic tissue, with a significantly lower degree of excitability and synchrony, and could not be linked to epilepsy.

These results help us to understand better the role of excitatory and inhibitory neuronal circuits in the generation of population events, and to define the subtle border between physiological and pathological synchronies.

Interictal activity is a hallmark of epilepsy diagnostics and is linked to neuronal hypersynchrony. Little is known about perturbations in human epileptic neocortical microcircuits, and their role in generating pathological synchronies. To explore hyperexcitability of the human epileptic network, and its contribution to convulsive activity, we investigated an in vitro model of synchronous burst activity spontaneously occurring in postoperative tissue slices derived from patients with or without preoperative clinical and electrographic manifestations of epileptic activity. Human neocortical slices generated two types of synchronies. Interictal‐like discharges (classified as epileptiform events) emerged only in epileptic samples, and were hypersynchronous bursts characterized by considerably elevated levels of excitation. Synchronous population activity was initiated in both epileptic and non‐epileptic tissue, with a significantly lower degree of excitability and synchrony, and could not be linked to epilepsy. However, in pharmacoresistant epileptic tissue, a higher percentage of slices exhibited population activity, with higher local field potential gradient amplitudes. More intracellularly recorded neurons received depolarizing synaptic potentials, discharging more reliably during the events. Light and electron microscopic examinations showed slightly lower neuron densities and higher densities of excitatory synapses in the human epileptic neocortex. Our data suggest that human neocortical microcircuits retain their functionality and plasticity in vitro, and can generate two significantly different synchronies. We propose that population bursts might not be pathological events while interictal‐like discharges may reflect the epileptogenicity of the human cortex. Our results show that hyperexcitability characterizes the human epileptic neocortical network, and that it is closely related to the emergence of synchronies.
Determination of Viscosity Versus Pressure by Means of a Clearance Seal
Authors: Christiansen Peter , Hansen Niels Schmidt , Lund Martin Thomas Overdahl , Spangenberg Jon , Bay Niels
Published: November 2017

This paper describes the construction and testing of a simple, experimental tool setup that enables determination of the pressure–viscosity relationship for high viscosity oils. Comparing the determined pressure–viscosity relationship with a reference rheometer measuring the viscosity at ambient pressure yields reasonable agreement. The computed viscosity at elevated pressures was well represented by the Chu and Cameron model.
Probabilistic Seismic Collapse Analysis of Jacket Offshore Platforms
Authors: Zarrin M. , Asgarian B. , Abyani M.
Published: November 2017

This paper analyses and evaluates the variability of seismic demand and capacity of a case study jacket offshore platform considering different sources of uncertainty. The aleatoric uncertainty due to variability of near-fault ground motions, as well as uncertain properties of the damping ratio, material elastic modulus, material yield strength, mass, and gravity load have been investigated. The main aim of this study is to pursue which sources of the uncertainty considerably affect the seismic response of the platform. To this end, the sensitivity analysis was conducted not only in the particular earthquake level, but also in all other ranges of intensity using incremental dynamic analysis (IDA) with a special focus on the seismic collapse fragility. In order to reduce the number of simulations, the Latin hypercube sampling (LHS) scheme has been utilized as an efficient sampling procedure to combine the effects of modeling random variables. The collapse fragility curves are derived for each of the model realizations created with LHS technique. Thereafter, the summarized random fragility curve is compared with the deterministic mean parameter model fragility curve. It is found that the uncertainty in the mass and gravity load on the platform are the most influential variables, which can notably alter the IDA and collapse fragility curves. Furthermore, the random combination of the considered sources of uncertainty shifts the median of collapse fragility away from the mean parameter model collapse fragility. Overall, the effects of the uncertainties do not lead to notable changes in the summarized collapse fragility curve.
Simultaneous Measurement of Free Surface Elevation and Three-Component Velocity Field Around a Translating Surface-Piercing Foil
Authors: Schock James , Dahl Jason
Published: November 2017

Two methods are investigated to simultaneously obtain both three-dimensional (3D) velocity field and free surface elevations (FSEs) measurements near a surface piercing foil, while limiting the equipment. The combined velocity field and FSE measurements are obtained specifically for the validation of numerical methods requiring simultaneous field data and free surface measurements for a slender body shape. Both methods use stereo particle image velocimetry (SPIV) to measure three component velocities in the flow field and both methods use an off the shelf digital camera with a laser intersection line to measure FSEs. The first method is performed using a vertical laser sheet oriented parallel to the foil chord line. Through repetition of experiments with repositioning of the laser, a statistical representation of the three-dimensional flow field and surface elevations is obtained. The second method orients the vertical laser sheet such that the foil chord line is orthogonal to the laser sheet. A single experiment is performed with this method to measure the three-dimensional three component (3D3C) flow field and free surface, assuming steady flow conditions, such that the time dimension is used to expand the flow field in 3D space. The two methods are compared using dynamic mode decomposition and found to be comparable in the primary mode. Utilizing these methods produces results that are acceptable for use in numerical methods verification, at a fraction of the capital and computing cost associated with two plane or tomographic particle image velocimetry (PIV).
A Dimensionless Model for Transient Turbulent Natural Convection in Isochoric Vertical Thermal Energy Storage Tubes
Authors: Lakeh Reza Baghaei , Wirz Richard E. , Kavehpour Pirouz , Lavine Adrienne S.
Published: November 2017

In this study, turbulent natural convection heat transfer during the charge cycle of an isochoric vertically oriented thermal energy storage (TES) tube is studied computationally and analytically. The storage fluids considered in this study (supercritical CO2 and liquid toluene) cover a wide range of Rayleigh numbers. The volume of the storage tube is constant and the thermal storage happens in an isochoric process. A computational model was utilized to study turbulent natural convection during the charge cycle. The computational results were further utilized to develop a conceptual and dimensionless model that views the thermal storage process as a hot boundary layer that rises along the tube wall and falls in the center to replace the cold fluid in the core. The dimensionless model predicts that the dimensionless mean temperature of the storage fluid and average Nusselt number of natural convection are functions of L/D ratio, Rayleigh number, and Fourier number that are combined to form a buoyancy-Fourier number.
Passive pumping for the parallel trapping of single neurons onto a microsieve electrode array
Authors: Frimat Jean-Philippe , Schurink Bart , Luttge Regina
Published: November 2017

Recent advances in brain-on-a-chip technology have led to the development of modified microelectrode arrays. Previously, the authors have contributed to this exciting field of neuroscience by demonstrating a fabrication process for producing microsieve chips that contain three-dimensional (3D) micropores at the electrodes [termed microsieve electrode arrays (μSEAs)]. This chip allows us to trap hundreds of single neuronal cells in parallel onto the electrodes [B. Schurink and R. Luttge, J. Vac. Sci. Technol., B 31, 06F903 (2013)]. However, trapping the neurons reproducibly under gentle, biocompatible conditions remains a challenge. The current setup involves the use of a hand-operated syringe that is connected to the back of the μSEA chip with a polydimethylsiloxane (PDMS) construct. This makes the capture process rather uncontrolled, which can lead to either cell damage by shear stress or the release of trapped neurons when unplugging the syringe and PDMS constructs. Although, the authors could achieve an efficient capture rate of single neurons within the 3D micropores (80%–90% filling efficiency), cell culture performance varied significantly. In this paper, the authors introduce a passive pumping mechanism for the parallel trapping of neurons onto the μSEA chip with the goal to improve its biological performance. This method uses the capillary pumping between two droplets (a “pumping droplet” on one side of the chip and a “reservoir droplet” on the other side) to create a stable and controllable flow. Due to simplification of the handling procedure, omitting the use of a syringe and additional connections to the μSEA chip, the set-up is compatible with real time microscopy techniques. Hence, the authors could use optical particle tracking to study the trapping process and record particle velocities by video imaging. Analyzing the particle velocities in the passive pumping regime, the authors can confirm a gentle uniform particle flow through the 3D micropores. The authors show that passive pumping particle velocity can be tightly controlled (from 5 to 7.5 to 10.4 μm/s) simply by changing the droplet volume of the pumping droplets from 20, 40, and 60 μl and keeping the reservoir drop constant (10 μl). The authors demonstrate that neuron capturing efficiency and reproducibility as well as neuronal network formation are greatly improved when using this passive pumping approach.
Safety and Pharmacokinetics of the Aminomethylcycline Antibiotic Omadacycline Administered to Healthy Subjects in Oral Multiple-Dose Regimens
Authors: Bundrant Lu Ann , Tzanis Evan , Garrity-Ryan Lynne , Bai Stephen , Chitra Surya , Manley Amy , Villano Stephen
Published: November 2017

Omadacycline, a first-in-class aminomethylcycline antibiotic, is related to tetracyclines but is structurally modified to circumvent mechanisms of resistance to tetracyclines. Omadacycline demonstrates potent activity against a broad range of pathogens, including drug-resistant strains, and is in late-stage development for treatment of acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia. Previous studies support an intravenous-to-oral transition regimen with 300-mg once-daily oral dosing. This phase 1 study investigated the pharmacokinetics and safety/tolerability of multiple oral omadacycline doses higher than 300 mg. Using a 3-period crossover design, healthy adults were randomized to receive oral omadacycline at 300, 450, and 600 mg in variable sequence (
n
= 26) or placebo (
n
= 7) once daily for 5 consecutive days per period. In plasma, omadacycline maximum concentration and total exposure increased with increasing dose but were less than dose proportional. The kinetics of omadacycline plasma accumulation were similar between dose levels; exposure on day 5 was ∼50% higher than that on day 1. Omadacycline plasma concentrations on day 1 of 450-mg dosing were similar to those on day 5 of 300-mg dosing. All doses were generally well tolerated, but the 600-mg dose was associated with more gastrointestinal adverse events.
Genetic Plasticity and Ethylmalonyl Coenzyme A Pathway during Acetate Assimilation in Rhodospirillum rubrum S1H under Photoheterotrophic Conditions
Authors: De Meur Quentin , Deutschbauer Adam , Koch Matthias , Wattiez Ruddy , Leroy Baptiste
Published: November 2017

Purple nonsulfur bacteria represent a promising resource for biotechnology because of their great metabolic versatility.
Rhodospirillum rubrum
has been widely studied regarding its metabolism of volatile fatty acid, mainly acetate. As the glyoxylate shunt is unavailable in
Rs. rubrum
, the citramalate cycle pathway and the ethylmalonyl-coenzyme A (CoA) pathway are proposed as alternative anaplerotic pathways for acetate assimilation. However, despite years of debate, neither has been confirmed to be essential. Here, using functional genomics, we demonstrate that the ethylmalonyl-CoA pathway is required for acetate photoassimilation. Moreover, an unexpected reversible long-term adaptation is observed, leading to a drastic decrease in the lag phase characterizing the growth of
Rs. rubrum
in the presence of acetate. Using proteomic and genomic analyses, we present evidence that the adaptation phenomenon is associated with reversible amplification and overexpression of a 60-kb genome fragment containing key enzymes of the ethylmalonyl-CoA pathway. Our observations suggest that a genome duplication and amplification phenomenon is not only involved in adaptation to acute stress but can also be important for basic carbon metabolism and the redox balance.

IMPORTANCE
Purple nonsulfur bacteria represent a major group of anoxygenic photosynthetic bacteria that emerged as a promising resource for biotechnology because of their great metabolic versatility and ability to grow under various conditions.
Rhodospirillum rubrum
S1H has notably been selected by the European Space Agency to colonize its life support system, called MELiSSA, due to its capacity to perform photoheterotrophic assimilation of volatile fatty acids (VFAs), mainly acetate. VFAs are valuable carbon sources for many applications, combining bioremediation of contaminated environments with the generation of added-value products. Acetate is one of the major volatile fatty acids generated as a by-product of fermentation processes. In
Rs. rubrum
, purple nonsulfur bacteria, the assimilation of acetate is still under debate since two different pathways have been proposed. Here, we clearly demonstrate that the ethylmalonyl-CoA pathway is the major anaplerotic pathway for acetate assimilation in this strain. Interestingly, we further observed that gene duplication and amplification, which represent a well-known phenomenon in antibiotic resistance, also play a regulatory function in carbon metabolism and redox homeostasis.
In Vitro
Enzymatic Depolymerization of Lignin with Release of Syringyl, Guaiacyl, and Tricin Units
Authors: Gall Daniel L. , Kontur Wayne S. , Lan Wu , Kim Hoon , Li Yanding , Ralph John , Donohue Timothy J. , Noguera Daniel R.
Published: November 2017

New environmentally sound technologies are needed to derive valuable compounds from renewable resources. Lignin, an abundant polymer in terrestrial plants comprised predominantly of guaiacyl and syringyl monoaromatic phenylpropanoid units, is a potential natural source of aromatic compounds. In addition, the plant secondary metabolite tricin is a recently discovered and moderately abundant flavonoid in grasses. The most prevalent interunit linkage between guaiacyl, syringyl, and tricin units is the β-ether linkage. Previous studies have shown that bacterial β-etherase pathway enzymes catalyze glutathione-dependent cleavage of β-ether bonds in dimeric β-ether lignin model compounds. To date, however, it remains unclear whether the known β-etherase enzymes are active on lignin polymers. Here we report on enzymes that catalyze β-ether cleavage from bona fide lignin, under conditions that recycle the cosubstrates NAD
+
and glutathione. Guaiacyl, syringyl, and tricin derivatives were identified as reaction products when different model compounds or lignin fractions were used as substrates. These results demonstrate an
in vitro
enzymatic system that can recycle cosubstrates while releasing aromatic monomers from model compounds as well as natural and engineered lignin oligomers. These findings can improve the ability to produce valuable aromatic compounds from a renewable resource like lignin.

IMPORTANCE
Many bacteria are predicted to contain enzymes that could convert renewable carbon sources into substitutes for compounds that are derived from petroleum. The β-etherase pathway present in sphingomonad bacteria could cleave the abundant β–O–4-aryl ether bonds in plant lignin, releasing a biobased source of aromatic compounds for the chemical industry. However, the activity of these enzymes on the complex aromatic oligomers found in plant lignin is unknown. Here we demonstrate biodegradation of lignin polymers using a minimal set of β-etherase pathway enzymes, the ability to recycle needed cofactors (glutathione and NAD
+
)
in vitro
, and the release of guaiacyl, syringyl, and tricin as depolymerized products from lignin. These observations provide critical evidence for the use and future optimization of these bacterial β-etherase pathway enzymes for industrial-level biotechnological applications designed to derive high-value monomeric aromatic compounds from lignin.
Quantifying the Survival of Multiple Salmonella enterica Serovars
In Vivo
via Massively Parallel Whole-Genome Sequencing To Predict Zoonotic Risk
Authors: Vohra Prerna , Bugarel Marie , Turner Frances , Loneragan Guy H. , Hope Jayne C. , Hopkins John , Stevens Mark P.
Published: November 2017

Salmonella enterica
is an animal and zoonotic pathogen of worldwide importance.
Salmonella
serovars that differ in their host and tissue tropisms exist. Cattle are an important reservoir of human nontyphoidal salmonellosis, and contaminated bovine peripheral lymph nodes enter the food chain via ground beef. The relative abilities of different serovars to survive within the bovine lymphatic system are poorly understood and constrain the development of control strategies. This problem was addressed by developing a massively parallel whole-genome sequencing method to study mixed-serovar infections
in vivo
.
Salmonella
serovars differ genetically by naturally occurring single nucleotide polymorphisms (SNPs) in certain genes. It was hypothesized that these SNPs could be used as markers to simultaneously identify serovars in mixed populations and quantify the abundance of each member in a population. The performance of the method was validated
in vitro
using simulated pools containing up to 11 serovars in various proportions. It was then applied to study serovar survival
in vivo
in cattle challenged orally with the same 11 serovars. All the serovars successfully colonized the bovine lymphatic system, including the peripheral lymph nodes, and thus pose similar risks of zoonosis. This method enables the fates of multiple genetically unmodified strains to be evaluated simultaneously in a single animal. It could be useful in reducing the number of animals required to study mixed-strain infections and in testing the cross-protective efficacy of vaccines and treatments. It also has the potential to be applied to diverse bacterial species which possess shared but polymorphic alleles.

IMPORTANCE
While some
Salmonella
serovars are more frequently isolated from lymph nodes rather than the feces and environment of cattle, the relative abilities of serovars to survive within the lymphatic system of cattle remain ill defined. A sequencing-based method which used available information from sequenced
Salmonella
genomes to study the dynamics of mixed-serovar infections
in vivo
was developed. The main advantages of the method include the simultaneous identification and quantification of multiple strains without any genetic modification and minimal animal use. This approach could be used in vaccination trials or in epidemiological surveys where an understanding of the dynamics of closely related strains of a pathogen in mixed populations could inform the prediction of zoonotic risk and the development of intervention strategies.
Referrers’ point of view on the referral process to neurosurgery and opinions on neurosurgeons: a large-scale regional survey in the UK
Authors: Amarouche Meriem , Neville Jonathan J , Deacon Simon , Kalyal Nida , Adams Nikita , Cheserem Beverly , Curley Daniel , DeSouza Ruth-Mary , Hafiz Fehmi , Jayawardena Tanya , Khetani Nishi , Matthews Diana , Mustoe Sophie , Okafor Sabrina , Padfield Olivia , Rao Ishani , Samir Reem , Tahir Hyder , Varghese Benjamin , Tolias Christos Michael
Published: November 2017

Objectives

There is an increased reliance on online referral systems (ORS) within neurosurgical departments across the UK. Opinions of neurosurgeons on ORS are extensively reported but those of referrers have hardly been sought. Our study aims at ascertaining our referring colleagues’ views on our ORS and its impact on patient care, their opinions on neurosurgeons and how to improve our referral process.

Setting

14 district general hospitals and one teaching hospital.

Participants

641 healthcare professionals across a range of medical and surgical specialties including doctors of all grades, nurses and physiotherapists. Survey responses were obtained by medical students using a smartphone application.

Results

Although 92% of respondents were aware of the ORS, 74% would routinely phone the on-call registrar either before or after making referrals online. The majority (44%) believed their call to relate to a life-threatening emergency. 62% of referrers considered the ORS helpful in informing patients’ care and 48% had a positive opinion of their interaction with neurosurgical registrars. On ways to improve the ORS, 50% selected email/text confirmation of response sent to referrers and 16% to referring consultants.

Conclusion

Our results confirm that referrers feel that using our ORS positively impacts patient care but that it remains in need of improvement in order to better suit our colleagues’ needs when it comes to managing neurosurgical patients. We feel that the promotion of neurosurgical education and mitigation of the effects of adverse workplace human factors are likely to achieve the common goal of neurosurgeons and referrers alike: a high standard in patient care.
A cross-sectional study examining associations between substance use frequency, problematic use and STIs among youth living with HIV
Authors: Gamarel Kristi E , Nichols Sharon , Kahler Christopher W , Westfall Andrew O , Lally Michelle A , Wilson Craig M
Published: November 2017

Objectives

This study sought to examine the prevalence of STIs and whether substance use frequency and/or problematic use—specifically alcohol, marijuana and other drugs—was associated with having an STI diagnosis among youth living with HIV (YLWH)

Methods

A sample of 823 YLWH were recruited at 14 adolescent HIV clinics through the Adolescent Medicine Trials Network for HIV Interventions. Study staff abstracted STI data from medical records for up to 26 weeks prior to participants’ completing a cross-sectional survey including the ASSIST (Alcohol, Smoking and Substance Involvement Screening Test), which measures substance use frequency and consequences.

Results

Almost one-third of youth had been diagnosed with an STI (30.5%) at the time of their baseline assessment. In multivariable analyses, those who engaged in weekly or greater marijuana use (adjusted OR (AOR)=10.66, 95% CI: 4.39 to 25.87, P<0.001) had an increased odds of being diagnosed with an STI. Additionally, youth who met alcohol use criteria for moderate (AOR=5.23, 95% CI: 2.50 to 10.93, P<0.001) and high risk (AOR=6.53, 95% CI: 1.20 to 35.68, P<0.05) alcohol use had an increased odds of being diagnosed with an STI compared with low-risk alcohol users.

Conclusions

Study findings underscore the need to investigate the role of greater frequency of marijuana use and problematic alcohol use in STI incidence among YLWH. Given the associations between both substance use frequency and problematic use in STI diagnoses among YLWH seen in HIV care settings, clinicians should use validated substance use screening tools which capture both frequencies and consequences in order to identify YLWH who may need further evaluation and treatment.
On non-exponential cosmological solutions with two factor spaces of dimensions m and 1 in the Einstein–Gauss–Bonnet model with a Λ-term
Authors: Ernazarov K. K.
Published: November 2017

We consider a [Formula: see text]-dimensional Einstein–Gauss–Bonnet (EGB) model with the cosmological [Formula: see text]-term. We restrict the metrics to be diagonal ones and find for certain [Formula: see text] class of cosmological solutions with non-exponential time dependence of two scale factors of dimensions [Formula: see text] and 1. Any solution from this class describes an accelerated expansion of [Formula: see text]-dimensional subspace and tends asymptotically to isotropic solution with exponential dependence of scale factors.
The structure and interaction mechanisms of C10H16@(13, 0)SWCNT under high pressure
Authors: Yao Zhen , Liu Chun-Jian , Lv Hang
Published: November 2017

The high-pressure deformation and polymerization of peapod structure (C[Formula: see text]H[Formula: see text] filled into (13, 0) single-walled carbon nanotube) is studied by using density function theory. The guest–host interaction mechanism under pressure is analyzed by combining the van der Waals (vdW) potential with the electron localization function (ELF). Our studies show that the cross-section of the filled single-walled carbon nanotube changes from a circle into an ellipse shape, and then into a walnut shape with the transition pressures of 3 GPa and 10 GPa, respectively. The intertubular bonding of adjacent tubes occurs at 17 GPa, 30 GPa, 32 GPa, 82 GPa and 152 GPa. The attractive and repulsive guest–host interactions are exhibited for the pressures lower and higher than 10 GPa, respectively. Except for the ambient pressure structure, six stable high pressure structures, which can hold their structures when the pressure is released, are identified by combining the systematic binding energy with geometry optimization.
Modified dark matter: Relating dark energy, dark matter and baryonic matter
Authors: Edmonds Douglas , Farrah Duncan , Minic Djordje , Ng Y. Jack , Takeuchi Tatsu
Published: November 2017

Modified dark matter (MDM) is a phenomenological model of dark matter, inspired by gravitational thermodynamics. For an accelerating universe with positive cosmological constant ([Formula: see text]), such phenomenological considerations lead to the emergence of a critical acceleration parameter related to [Formula: see text]. Such a critical acceleration is an effective phenomenological manifestation of MDM, and it is found in correlations between dark matter and baryonic matter in galaxy rotation curves. The resulting MDM mass profiles, which are sensitive to [Formula: see text], are consistent with observational data at both the galactic and cluster scales. In particular, the same critical acceleration appears both in the galactic and cluster data fits based on MDM. Furthermore, using some robust qualitative arguments, MDM appears to work well on cosmological scales, even though quantitative studies are still lacking. Finally, we comment on certain nonlocal aspects of the quanta of modified dark matter, which may lead to novel nonparticle phenomenology and which may explain why, so far, dark matter detection experiments have failed to detect dark matter particles.
A Class of Symmetric Factored Approximate Inverses and Hybrid Two-Level Solver
Authors: Kyziropoulos Panagiotis E. , Filelis-Papadopoulos Christos K. , Gravvanis George A.
Published: November 2017

A new class of symmetric factored approximate inverses is proposed and used in conjunction with the Preconditioned Conjugate Gradient method for solving sparse symmetric linear systems. Additionally, a new hybrid two-level solver is proposed utilizing a block independent set reordering, in order to create the two level hierarchy. The Schur complement is formed explicitly by inverting the blocks created by reordering. Then, the preconditioned conjugate gradient method is used in conjunction with the symmetric factored approximate inverse to solve the reduced order linear system. Furthermore, numerical results on the performance and convergence behavior for solving various model problems are presented.
Synthesis, characterization and photochemical properties of metallo porphyrazines substituted with alkyl linked carbazole, benzoazepine and phenothiazine moieties
Authors: Olgaç Remziye , Baygu Yasemin , Yıldız Burak , Gök Yaşar , Köksoy Baybars , Durmuş Mahmut
Published: November 2017

Novel octa-phenotiazine, octa-benzoazepine and octa-carbazole substituted magnesium(II) (MgPz-I-III) and zinc(II) (ZnPz-I-III) porphyrazines were synthesized from 2,3-bis[6-(4a,10a-dihydro-phenothiazin-10-yl)-hexylsulfanyl]-but-2-enedinitrile (5), 2,3-bis [6-(4a,11a-dihydro-dibenzo[b,f]azepin-5-yl)-hexysulfan-yl]-but-2-enedinitrile (8) and 2,3-bis(6-carbazol-9-yl-hexylsulfanyl)-but-2-enedinitrile (10), respectively. These dinitrile derivatives 5, 8 and 10 were also prepared by the reaction of 1,2-dicyano-1,2-ethylenedithiolate di-sodium salt (4) with 10-(6-bromohexyl)-10H-phenothiazine (3), 5-(6-bromohexyl)-5H-diben-zo[b,f]azepine (7) and 9-(6-bromo-hexyl)-9H-carbazole (9), respectively. Porphyrazino-zinc(II) complexes were synthesized by one-step reaction using Zn(BuO)[Formula: see text] as a template agent. All the novel compounds were characterized by elemental analysis and different spectroscopic methods such as [Formula: see text]H NMR, [Formula: see text]C NMR, FT-IR, UV-Vis and mass. The photochemical properties including photodegradation and singlet oxygen generation for magnesium(II) and zinc (II) porphyrazine complexes were studied in dimethylsulfoxide solutions for determination of their photosensitizer behaviors.
Fuzzy Logic-Based Quality of Service Evaluation for Multimedia Transmission over Wireless Ad Hoc Networks
Authors: Umoh Uduak , Asuquo Daniel
Published: November 2017

This paper proposes a fuzzy logic (FL) model for evaluation of quality of service (QoS) in multimedia transmission over ad hoc networks as an effective mechanism for QoS management. It aims at minimizing the negative effects of major QoS parameters, (jitter, delay, packet loss) sustaining efficiency and reliability of data deliveries and improving overall system performance. Both triangular membership function (TMF) and Gaussian membership function (GMF) are adopted to demonstrate their effects in FL-QoS evaluation. The proposed approaches are implemented in Matlab/Simulink. Results indicate that input conditions have varying level of influences on the output based on the MFs used. It is generally observed that QoS fuzzy control with TMF gives a better performance than GMF. Typically, it is also noted that when the input conditions are selected at 50[Formula: see text]ms delay, 5[Formula: see text]ms jitter and 50% packet loss, we obtain 79% and 71% output responses with TMF and GMF, respectively. This shows that TMF method can control QoS in a multimedia transmission over ad hoc wireless network more effectively with good service output response than GMF. Generally, the paper shows that FL is capable of measuring network performance and predicting any QoS deterioration without complex mathematical calculation, to provide an improved QoS for customers’ satisfaction.
Wind Power Prediction Using Cluster Based Ensemble Regression
Authors: Tasnim Sumaira , Rahman Ashfaqur , Oo Amanullah Maung Than , Haque Md Enamul
Published: November 2017

Accurate prediction of wind power is of vital importance for demand management. In this paper, we adopt a cluster-based ensemble framework to predict wind power. Natural groups/clusters exist in datasets and learning algorithms benefit from group/cluster wise learning — a philosophy that is not well explored for wind power prediction. The research presented in this paper investigates this philosophy to predict wind power by using an ensemble of regression models on natural clusters within wind data. We have conducted a series of experiments on a large number of locations across Australia and analyzed the existence of clusters within wind data, suitability of linear and nonlinear regression models for the proposed framework, and how well the cluster-based ensemble performs against the situation when no clustering is done. Experimental results demonstrate prediction improvement as high as 17.94% through the usage of the cluster-based ensemble regression algorithm.
Building Efficient Key-Value Stores via a Lightweight Compaction Tree
Authors: Yao Ting , Wan Jiguang , Huang Ping , He Xubin , Wu Fei , Xie Changsheng
Published: November 2017

Log-Structure Merge tree (LSM-tree) has been one of the mainstream indexes in key-value systems supporting a variety of write-intensive Internet applications in today’s data centers. However, the performance of LSM-tree is seriously hampered by constantly occurring compaction procedures, which incur significant write amplification and degrade the write throughput. To alleviate the performance degradation caused by compactions, we introduce a lightweight compaction tree (LWC-tree), a variant of LSM-tree index optimized for minimizing the write amplification and maximizing the system throughput. The lightweight compaction drastically decreases write amplification by appending data in a table and only merging the metadata that have much smaller size. Using our proposed LWC-tree, we have implemented three key-value LWC-stores on different storage mediums including Shingled Magnetic Recording (SMR) drives, Solid State Drives (SSD), and conventional Hard Disk Drives (HDDs). The LWC-store is particularly optimized for SMR drives, as it eliminates the multiplicative I/O amplification from both LSM-trees and SMR drives. Due to the lightweight compaction procedure, LWC-store reduces the write amplification by a factor of up to 5× compared to the popular LevelDB key-value store. Moreover, the random write throughput of the LWC-tree on SMR drives is significantly improved by up to 467% even compared with LevelDB on conventional HDDs. Furthermore, LWC-tree has wide applicability and delivers impressive performance improvement in various conditions, including different storage mediums (i.e., SMR, HDD, SSD) and various value sizes and access patterns (i.e., uniform and Zipfian).
GDS-LC
Authors: Hou Binbing , Chen Feng
Published: November 2017

Successfully integrating cloud storage as a primary storage layer in the I/O stack is highly challenging. This is essentially due to two inherent critical issues: the high and variant cloud I/O latency and the per-I/O pricing model of cloud storage. To minimize the associated latency and monetary cost with cloud I/Os, caching is a crucial technology, as it directly influences how frequently the client has to communicate with the cloud. Unfortunately, current cloud caching schemes are mostly designed to optimize miss reduction as the sole objective and only focus on improving system performance while ignoring the fact that various cache misses could have completely distinct effects in terms of latency and monetary cost.

In this article, we present a cost-aware caching scheme, called
GDS-LC
, which is highly optimized for cloud storage caching. Different from traditional caching schemes that merely focus on improving cache hit ratios and the classic cost-aware schemes that can only achieve a single optimization target, GDS-LC offers a comprehensive cache design by considering not only the access locality but also the object size, associated latency, and price, aiming at enhancing the user experience with cloud storage from two aspects: access latency and monetary cost. To achieve this, GDS-LC virtually partitions the cache space into two regions: a high-priority latency-aware region and a low-priority price-aware region. Each region is managed by a cost-aware caching scheme, which is based on GreedyDual-Size (GDS) and designed for a cloud storage scenario by adopting clean-dirty differentiation and latency normalization. The GDS-LC framework is highly flexible, and we present a further enhanced algorithm, called
GDS-LCF
, by incorporating access frequency in caching decisions. We have built a prototype to emulate a typical cloud client cache and evaluate GDS-LC and GDS-LCF with Amazon Simple Storage Services (S3) in three different scenarios: local cloud, Internet cloud, and heterogeneous cloud. Our experimental results show that our caching schemes can effectively achieve both optimization goals: low access latency and low monetary cost. It is our hope that this work can inspire the community to reconsider the cache design in the cloud environment, especially for the purpose of integrating cloud storage into the current storage stack as a primary layer.
Mosaicism in Cutaneous Disorders
Authors: Lim Young H. , Moscato Zoe , Choate Keith A.
Published: November 2017

Genetic mosaicism arises when a zygote harbors two or more distinct genotypes, typically due to de novo, somatic mutation during embryogenesis. The clinical manifestations largely depend on the differentiation status of the mutated cell; earlier mutations target pluripotent cells and generate more widespread disease affecting multiple organ systems. If gonadal tissue is spared—as in somatic genomic mosaicism—the mutation and its effects are limited to the proband, whereas mosaicism also affecting the gametes, such as germline or gonosomal mosaicism, is transmissible. Mosaicism is easily appreciated in cutaneous disorders, as phenotypically distinct mutant cells often give rise to lesions in patterns determined by the affected cell type. Genetic investigation of cutaneous mosaic disorders has identified pathways central to disease pathogenesis, revealing novel therapeutic targets. In this review, we discuss examples of cutaneous mosaicism, approaches to gene discovery in these disorders, and insights into molecular pathobiology that have potential for clinical translation.
Intraoperative Use of CBCT for Identification and Localization of Calcified Canals: A Clinical Technique
Authors: Floratos Spyros , Miltiadous Maria-Elpida
Published: November 2017

Localization of calcified canals has always been a challenge in the field of endodontics. The following report of three cases describes a technique for the identification and negotiation of obliterated canals by use of cone beam computed tomography (CBCT) intraoperatively. Canal orifices could not be found clinically in all three cases. Gutta-percha points were placed and compacted at the position where the canal orifices were estimated to be. Intraoperative CBCT was taken, and the distance between the gutta-percha points and the canal orifices was calculated at all planes of space in the first two cases. In the third case, only one canal orifice could be identified due to obliteration of the other canals.
A Singleton Infant with Bilateral Renal Agenesis and Normal Pulmonary Function
Authors: George Lovya , Manimtim Winston , Sharma Jotishna
Published: November 2017

Bilateral renal agenesis leads to anhydramnios and other sequelae including pulmonary hypoplasia. There have been rare case reports of normal pulmonary function in the presence of bilateral renal agenesis in monoamniotic discordant twins, but this has never been reported in a singleton pregnancy. The few reported cases in twins have all been fatal in the neonatal period with no reported cases of survival beyond 2 months. We describe the first case of a singleton infant with bilateral renal agenesis who had normal pulmonary function and did well on peritoneal dialysis for 4 years while awaiting a renal transplant.
Endovascular Repair of Aortobronchial Fistula due to Saccular Aneurysm of Thoracic Aorta
Authors: Tigkiropoulos Konstantinos , Stavridis Kyriakos , Lazaridis Ioannis , Saratzis Nikolaos
Published: November 2017

Aortobronchial fistula (ABF) is a rare condition which can be lethal if left untreated. Open surgical treatment carries high morbidity and mortality. Recent advances in endovascular technology have made thoracic endovascular aortic repair (TEVAR) the treatment of choice. We present a successful endovascular repair of aortobronchial fistula due to a saccular aneurysm of descending thoracic aorta.
Bacterial Diversity in Feline Conjunctiva Based on 16S rRNA Gene Sequence Analysis: A Pilot Study
Authors: Płoneczka-Janeczko Katarzyna , Bania Jacek , Bierowiec Karolina , Kiełbowicz Maciej , Kiełbowicz Zdzisław
Published: November 2017

Changes in the microbial populations in the conjunctival sacs of animals have traditionally been evaluated using conventional microbiology techniques. The goal of this study was to examine the suitability of a methodology which may reveal a previously unknown microbiome inhabiting feline conjunctival membranes. In the present study, we determined the microbial diversity in feline conjunctivas based on 16S rRNA gene sequence analysis. Five taxa not described earlier in veterinary ophthalmology (i.e.,Staphylococcus caprae,Staphylococcus succinus, Propionibacterium acnes, Psychrobacter faecalis,andBacillus subtilis) were identified in feline conjunctivas with a high similarity (99-100%). The study demonstrates that the feline conjunctival sacs are inhabited by much more rich and diverse microbial communities than previously thought using culture-based methods. From the clinical perspective, this could suggest that other laboratory procedures (e.g., extended incubation time in the case of Actinobacteria, formerly order Actinomycetales) or a new tool like culture-independent approaches (next-generation DNA sequencing) should be taken into account.
A Network-Based Dynamic Analysis in an Equity Stock Market
Authors: Eberhard Juan , Lavin Jaime F. , Montecinos-Pearce Alejandro
Published: November 2017

We study how changes in the structure of a brokers’ transaction network affect the probability with which the returns and volume of the traded financial assets change significantly. We analyze how the dynamics of the brokers’ transaction network are associated with the returns and volume observed in the Chilean stock market. To do this, we construct and validate an index that synthesizes the daily changes of the brokers’ transaction network structure of equity market transactions. We find that the changes of this structure are significantly correlated with variables that describe the local and international economic-financial environments. In addition, changes in the brokers’ transaction network structure are associated with a greater probability of positive shocks of more than two standard deviations in the stock exchange index return and total traded stock volume. These results suggest that the structure of the brokers’ trading relations plays a role in determining the returns and volume of transactions in the Chilean stock market.
Comparison between Peritoneal Macrophage Activation by Bougainvillea xbuttiana Extract and LPS and/or Interleukins
Authors: Arteaga Figueroa Lluvia , Abarca-Vargas Rodolfo , García Alanis Claudia , Petricevich Vera L.
Published: November 2017

Activation of macrophages may be one of the possible approaches in modulating inflammation. We previously reported that Bougainvillea xbuttiana extract showed an immunomodulatory activity. Here we compare the activation of macrophages exposed to B. xbuttiana extract and compare it with the other treatments such as LPS, IL-4, and IL-10. The cytotoxic effect of extract on peritoneal macrophages was determined by the technique of violet crystal staining. To verify the activation of macrophages we used the tests of vacuolization, hydrogen peroxide production, and percentages of cellular expansion and phagocytosis. The levels of interleukins secreted by macrophages treated with the extract, LPS, and cytokines were determined by the biological assay for the determination of TNF levels and by ELISA for all other interleukins. NO levels were evaluated by colorimetric reactions using Griess reagent. Our results showed that B. xbuttiana extract induced (a) low cytotoxicity percentages, (b) increased vacuolization, hydrogen peroxide production and cell expansion and phagocytosis percentages, and (c) decreased production of TNF-α, IFN-γ, IL-1β, and IL-6 and potentiated production of IL-4, IL-10 and TGF-β. These results suggest that B. xbuttiana extract was able to activate the murine macrophages in a manner similar to those macrophages exposed to IL-4 and IL-10.
Preeruptive Intracoronal Radiolucencies: Detection and Nine Years Monitoring with a Series of Dental Radiographs
Authors: Manmontri Chanika , Mahasantipiya Phattaranant May , Chompu-inwai Papimon
Published: November 2017

Preeruptive intracoronal radiolucencies (PEIRs) are mostly incidentally found by routine radiographic examination of unerupted teeth. PEIRs are classified into two types according to the nature of the lesion: progressive and nonprogressive. A case report of a 17-year-old boy with a nonprogressive PEIR on the permanent mandibular left second molar is presented. The lesion was initially detected on an unerupted tooth at age eight years, eight months. It was clinically and radiographically assessed yearly. Cone beam computed tomography (CBCT) was used to evaluate the lesion’s size and location when the patient was 11 and 14 years old. The assessments confirmed that the lesion was nonprogressive and had no connection to the pulp or oral cavity. Due to the static nature of the detected PEIR during the nine-year follow-up period, the patient’s low caries-risk status, and high patient and parental cooperation in periodic dental care, it was decided to place resin sealant on the affected tooth and monitor the lesion without any operative treatment.