bluuebunny/crossref_metadata_2025 huggingface dataset:
Energy Conversion by Means of MHD Shock-Wave Generators Combined With Closed-Cycle Gas Turbines
Authors: Stingelin V. , Budliger J. P.
Published: April 2015

The principle of the operation and the basic features of shock-wave MHD generators are described. Such generators may serve as topping devices to closed-cycle gas turbines, giving the possibility of using heat source temperatures of a few hundred degrees in excess to the inlet temperatures to the gas turbines. Cycle efficiencies and specific power ratings can be increased considerably by means of such topping devices.
Distinctions Between Two Types of Self Excited Gas Oscillations in Vaneless Radial Diffusers
Authors: Abdelhamid A. N. , Bertrand J.
Published: April 2015

Experiments were conducted to determine the characteristics of oscillating flows in a centrifugal compression system with vaneless diffusers. The system was operated without a diffuser and with eight different diffuser configurations to determine the effects of diffuser diameter and width ratios on the unsteady behavior of the system. Mean and fluctuating velocity and static pressure measurements were carried out in the time and frequency domains. The system without a diffuser was found to be stable at all operating conditions. The installation of any of the eight diffusers resulted in the generation of self-excited oscillations at some operating conditions. It was found that the critical flow coefficient at which onset of oscillations was observed increased as the diffuser width ratio was decreased and as the diameter ratio was increased. Comparison between the characteristics of the oscillations observed in the present study and those observed by other investigators indicate that rotating stall in two geometrically similar diffusers can be an order of magnitude different in the non-dimensional rotational speed and level of unsteady pressure fluctuations. These differences point towards the possibility of existence of more than one set of flow conditions which could lead to the occurrence of the unsteady phenomena.
A Multivariable Controller for an Automotive Gas Turbine
Authors: Winterbone D. E. , Munro N. , Nuske D. J.
Published: April 2015

A complete control system design study is described, starting with a non-linear mathematical model and finishing with the control hardware. The basic objective of the study was to design a controller which reduced the characteristically poor response of the two-shaft automotive gas turbine. This was achieved by identifying the reasons for the acceleration delay and then designing the controller to compensate for them. The gas turbine was simulated by means of a quasi-steady non-linear thermodynamic model implemented on a digital computer. Careful manipulation of the equations enabled the model to run in real-time. This model was linearized at various operating points and the transfer functions obtained were compared with those measured on the plant. The control system was designed using Rosenbrock’s multivariable inverse Nyquist array technique. These compensators were grafted onto the original single loop control box and fitted to the engine. The results obtained on the engine test bed are compared with those using the original controller. A very large reduction in response lag is obtained with the multivariable control system.
Ceramic Applications in Turbine Engines
Authors: Helms H. E.
Published: April 2015

As part of the Department of Energy activities to reduce turbine engine fuel consumption, Detroit Diesel Allison (DDA) has been actively involved in a program to apply ceramic components and demonstrate improved cycle efficiency in the existing 404/505 vehicular gas turbine engine. Ceramic components will permit increased gas turbine operating temperatures and improve cycle efficiency. Initial ceramic components that have been engine tested and evaluated at an engine operating temperature of 1038°C (1900°F) include regenerators, vanes, and turbine tip shrouds. Engine test experience totals over 4000 hr on aluminum silicate regenerators, 1400 hr on silicone carbide nozzle vanes and 500 hr on silicon carbide turbine tip shrouds.
An Overview of Photovoltaic Power Systems
Authors: Backus C. E.
Published: April 2015

The United States is supporting a very aggressive research and development program in the field of photovoltaics. The goals of this program are to reduce the cost of solar cell arrays to a capital cost of 50¢/peak watt by the year 1986. The long-term goals are to achieve 10 to 30¢/peak watt by 1990 or 2000. The photovoltaic community is optimistic that the 1986 goals will be met with the use of silicon solar cells. The longer term goal may require the development of new thin film photovoltaic devices. As the price of solar cell arrays continues to decrease; the number of applications that are economically justified increases. The present production rates of photovoltaic arrays are close to 1 MW of production per year. The maximum expected efficiencies of 20 to 25 percent have already been achieved. Thus, cost reduction must come about through producing cells per unit area more cheaply. A separate alternative for producing low cost electricity from solar cells is to concentrate sunlight onto the cell, thus reducing the area of the cell per unit electrical output. Concentration systems also make available the option of using multiple cells to increase the overall conversion of sunlight to electricity. One two-cell concentration system has already demonstrated 28.5 percent efficiency.
Mississippi County Community College Solar Photovoltaic Total Energy Project
Authors: Henry E. M.
Published: April 2015

Mississippi County Community College at Blytheville, Arkansas, will derive its total electrical and thermal energy demand from an actively cooled photovoltaic energy system being developed under the management of TEAM, Inc. of Springfield, Virginia. The facility has a design peak electrical requirement for 240 kw to be supplied by a 26-sun concentrating collector field that fully tracks E-W. A 2.4 megawatt-hour electrical energy storage system under consideration is an iron redox system using FeCl2 electrolyte and pressure-molded carbon/PVC electrodes. The power conditioning system will include a 300-kw solid-state inverter to furnish 480-v, three-phase, 60-Hz ac to the College, and appropriate switching to acquire utility company power in emergencies. Process control includes the capability to gather vital signs on the collectors, thermal loop, electrical storage and building demands, and to provide closed-loop tracking and all control signals for energy efficient operation of the total system.
Novel Ceramic Receiver for Solar Brayton Systems
Authors: Jarvinen P. O.
Published: April 2015

Substantial progress is reported in the development of a high-temperature seal for a solar heated-air cavity receiver during the first six months of the DOE-sponsored advanced development program. Mechanical dome sealing methods are selected as the preferred sealing approach and a free-standing hemispherical dome contact-type seal and a clamped shallow dome seal are chosen for preliminary design, analysis, and fabrication. Analytical and experimental investigations establish the technological foundation of the seal concepts by demonstrating that ceramic domes can be designed to support the combined pressure, thermal stress, and temperature loads of a heated-air receiver, that a mechanical contact seal with a leak rate which is two orders less than the design goal leak rate is feasible, and that metallization of ceramics and the formation of an alternative brazed diaphragm seal are possible.
Draft Genome Sequence of
Ruminoclostridium
sp. Ne3, Clostridia from an Enrichment Culture Obtained from Australian Subterranean Termite,
Nasutitermes exitiosus
Authors: Wang Han , Lin Hai , Tran-Dinh Nai , Li Dongmei , Greenfield Paul , Midgley David J.
Published: April 2015

The draft genome sequence of
Ruminoclostridium
sp. Ne3 was reconstructed from the metagenome of a hydrogenogenic microbial consortium growing on xylan. The organism is likely the primary hemicellulose degrader within the consortium.
Genome Sequence of a Copper-Resistant Strain of Acidovorax citrulli Causing Bacterial Fruit Blotch of Melons
Authors: Wang Tielin , Yang Yuwen , Zhao Tingchang
Published: April 2015

Bacterial fruit blotch (BFB) of melons is a seed-borne disease caused by
Acidovorax citrulli
. We determined the draft genome of
A. citrulli
Tw6. The strain was isolated from a watermelon collected from Beijing, China. The
A. citrulli
Tw6 genome contains 5,080,614 bp and has a G+C content of 68.7 mol%.
Whole-Genome Sequences of Eight Campylobacter jejuni Isolates from Wild Birds
Authors: Shyaka Anselme , Kusumoto Akiko , Asakura Hiroshi , Kawamoto Keiko
Published: April 2015

We present here the draft genome sequences of 8
Campylobacter jejuni
strains isolated from wild birds. The strains were initially isolated from swabs taken from resident wild birds in the Tokachi area of Japan. The genome sizes range from 1.65 to 1.77 Mbp.
Complete Genome Sequence of a Western Siberian
Lymantria dispar
Multiple Nucleopolyhedrovirus Isolate
Authors: Kabilov Marsel R. , Martemyanov Vyacheslav V. , Tupikin Alexey E. , Baturina Olga A. , Belousova Irina A. , Bondar Alexander A. , Ilyinykh Alexandr V.
Published: April 2015

A novel strain of
Lymantria dispar
multiple nucleopolyhedrovirus (LdMNPV-27) was isolated from dead larvae of a Western Siberian (WS) population of gypsy moths (
Lymantria dispar
L.). We report the complete genome sequence of this strain, comprising 164,108 bp and double-stranded circular DNA encoding 162 predicted open reading frames.
Complete Genome Sequence of
Paenibacillus
sp. Strain IHBB 10380 Using PacBio Single-Molecule Real-Time Sequencing Technology
Authors: Pal Mohinder , Swarnkar Mohit K. , Thakur Rishu , Kiran Shashi , Chhibber Sanjay , Singh Anil K. , Gulati Arvind
Published: April 2015

The complete genome sequence of 5.77 Mb is reported for
Paenibacillus
sp. strain IHBB 10380, isolated from the cold desert area of the northwestern Himalayas and exhibiting amylase and cellulase activities. The gene-coding clusters predicted the presence of genes for hydrolytic enzymes in the genome.
Draft Genome Sequence of Erythromycin-Resistant Streptococcus gallolyticus subsp.
gallolyticus
NTS 31106099 Isolated from a Patient with Infective Endocarditis and Colorectal Cancer
Authors: Kambarev Stanimir , Caté Clément , Corvec Stéphane , Pecorari Frédéric
Published: April 2015

Streptococcus gallolyticus
subsp.
gallolyticus
is known for its close association with infective endocarditis and colorectal cancer in humans. Here, we report the draft genome sequence of highly erythromycin-resistant strain NTS 31106099 isolated from a patient with infective endocarditis and colorectal cancer.
When myopathy breaks the rules: a late-onset distal presentation
Authors: Newby Rachel , Jamieson Stuart , Udd Bjarne , Alty Jane
Published: April 2015

Myopathies typically present with proximal or generalised muscle weakness, but it is important for clinicians to recognise they may also have other distributions. This paper describes a case ofdistalmyopathy that was confirmed genetically as ZASP (Z-band alternatively spliced PDZ motif-containing protein) myofibrillar myopathy (MFM). MFMs are particularly topical because the genetic basis of several have recently been established, enabling diagnosis of conditions previously labelled ‘idiopathic myopathy’, and shedding new light on their pathophysiology. This paper describes a purely distal lower limb phenotype of ZASP MFM, the pathophysiology of ZASP and other MFMs, and the differential diagnosis of late-onset distal symmetrical weakness. The case includes several learning points: ZASP MFM is a new diagnosis; it should be included in differential diagnoses for late-onset myopathy, especially if there is a distal pattern or autosomal dominant inheritance; testing for cardiomyopathy is recommended, and a genetic test is now available.
Medication incidents in primary care medicine: protocol of a study by the Swiss Federal Sentinel Reporting System
Authors: Gnädinger Markus , Ceschi Alessandro , Conen Dieter , Herzig Lilli , Puhan Milo , Staehelin Alfred , Zoller Marco
Published: April 2015

Background/rationale

Patient safety is a major concern in healthcare systems worldwide. Although most safety research has been conducted in the inpatient setting, evidence indicates that medical errors and adverse events are a threat to patients in the primary care setting as well. Since information about the frequency and outcomes of safety incidents in primary care is required, the goals of this study are to describe the type, frequency, seasonal and regional distribution of medication incidents in primary care in Switzerland and to elucidate possible risk factors for medication incidents.

Methods and analysis

Study design and setting: We will conduct a prospective surveillance study to identify cases of medication incidents among primary care patients in Switzerland over the course of the year 2015.Participants: Patients undergoing drug treatment by 167 general practitioners or paediatricians reporting to the Swiss Federal Sentinel Reporting System.Inclusion criteria: Anyerroneousevent, as defined by the physician, related to the medication process and interfering with normal treatment course.Exclusion criteria: Lack of treatment effect, adverse drug reactions or drug–drug or drug–disease interactionswithoutdetectable treatment error.Primary outcome: Medication incidents.Risk factors: Age, gender, polymedication, morbidity, care dependency, hospitalisation.Statistical Analysis: Descriptive statistics to assess type, frequency, seasonal and regional distribution of medication incidents and logistic regression to assess their association with potential risk factors.Estimated sample size: 500 medication incidents.Limitations:We will take into account under-reporting and selective reporting among others as potential sources of bias or imprecision when interpreting the results.

Ethics and dissemination

No formal request was necessary because of fully anonymised data. The results will be published in a peer-reviewed journal.

Trial registration number

NCT0229537.
THE ROLE OF ANTICIPATORY POSTURAL ADJUSTMENTS AND COMPENSATORY CONTROL OF POSTURE IN BALANCE CONTROL OF PATIENTS WITH MULTIPLE SCLEROSIS
Authors: MEHRAVAR MOHAMMAD , YADOLLAH-POUR NAVA , TAJALI SHIRIN , SHATERZADEH-YAZDI MOHAMMAD-JAFAR , MAJDINASAB NASTARAN
Published: April 2015

Impaired balance is one of the most disabling multiple sclerosis (MS) symptoms. It is known that, in the presence of predictable perturbations, the central nervous system (CNS) utilizes both anticipatory (APAs) and compensatory (CPAs) postural adjustments to maintain balance. The main purpose of this study was to investigate the relationship between APAs and CPAs during self-induced postural perturbation in patients with MS. Participants performed a load release task while standing on a force platform. Electrical activity of six leg and trunk muscles, as well as displacements of the center of pressure (COP), was recorded. The results revealed significant APAs deficits in MS patients reflected in short APAs duration and reduced magnitude. The reduced APAs were not accompanied by significant compensatory muscle activity. It can be concluded that there is an impairment of feed-forward postural control in MS, and feedback-based mechanisms (CPAs) are unable to compensate for these APA deficits. These results should be considered in the rehabilitation programs for balance training of MS patients.
A DFT investigation of axial N-donor ligands effects on the high valent manganese-oxo meso-tetraphenyl porphyrin
Authors: Kavousi Hossein , Rezaeifard Abdolreza , Raissi Heidar , Jafarpour Maasoumeh
Published: April 2015

The effect of different electronic and structural nitrogen donors (L) on the N ( ax )- Mn - O properties in the high valent manganese-oxo meso-tetraphenylporphyrin intermediate is investigated by the density functional B3LYP method with 6-31g* basis set. The geometric structures, frontier molecular orbitals, thermodynamic parameters and physical properties such as chemical potential and chemical hardness of [( TPP )( L ) MnO ]+ complexes in the gas phase as well as water solution are calculated. Our theoretical results confirm that the Mn - O distances in [( TPP )( L ) MnO ]+ species decrease by replacing imidazoles with pyridines, amins as well as electron-poor and hindered nitrogen donors resulting from extending the Mn – N ( ax ) bonds. These results are supported by vibrational frequencies, atoms in molecules (AIM) and natural bond orbital (NBO) analysis. It is worth mentioning that the co-catalytic activity trend of different nitrogen donors observed experimentally in the presence of title Mn porphyrin is consistent with the calculated Mn – N ( ax ) and Mn – O bond lengths in this work.
Natural Frequency Analysis of 2D-FGM Sectorial Plate with Variable Thickness Resting on Elastic Foundation Using 2D-DQM
Authors: Satouri S. , Asanjarani A. , Satouri A.
Published: April 2015

In this paper, free vibration of two-dimensional functionally graded (2D-FG) sectorial plate with variable thickness resting on Winkler–Pasternak elastic foundation has been studied. It is assumed that the plate properties vary continuously through its both circumference and thickness according to power law distribution of the volume fraction. Primarily, the motion equations have been derived based on first order shear deformation theory (FSDT). The numerical two-dimensional differential quadrature method (2D-DQM) has been employed to solve the motion equations. Four different kinds of boundary condition are considered. The effects of geometrical and elastic foundation parameters along with 2D-FG power indices effects on the natural frequencies have been studied. Also the frequency parameters of the sectorial plate with uniform, linear and nonlinear variation of thickness for various boundary conditions have been computed and the effects of variable thickness parameters on natural frequency have been investigated.
Creep Effect Analysis at the Friction Interface of a Rotary Ultrasonic Motor
Authors: Chen Chao , She Chongmin
Published: April 2015

Theoretical and experimental studies for the creep mechanism at the friction interface between rotor and stator of traveling wave type rotary ultrasonic motors (TRUM) are performed in this work. A modeling method is developed to investigate the creep and the distributed contact pressure in the friction interface for the piezoelectric composite stator with complex geometries. The annular laminated structure of the stator is discretized into a semi-analytical plate element in the radial direction, and the teeth on top of the stator are modeled by the finite element (FE) method. Then a coupled approach for the continuous plate and FE discretized teeth is proposed to investigate the interface contact mechanism. Finally, the accelerated aging tests for TRUM are conducted to study the creep effect in the friction layer during the long-term storage, the startup state is investigated experimentally by the transient characteristics measurement system. It is shown that transient characteristics of TRUM are strongly affected by the creep effect at the friction interface. The vibration response of the stator is weakened by the creep of the contact layer, and the amplitude of the piezoelectric composite plate decreases with increasing creep percentage. It is theoretically and experimentally proved that the creep percentage of over 20% can lead to the startup failure of TRUM.
A Convex Duality Method for Optimal Liquidation with Participation Constraints
Authors: Guéant Olivier , Lasry Jean-Michel , Pu Jiang
Published: April 2015

In spite of the growing consideration for optimal execution in the financial mathematics literature, numerical approximations of optimal trading curves are almost never discussed. In this paper, we present a numerical method to approximate the optimal strategy of a trader willing to unwind a large portfolio. The method we propose is very general as it can be applied to multi-asset portfolios with any form of execution costs, including a bid-ask spread component, even when participation constraints are imposed. Our method, based on convex duality, only requires Hamiltonian functions to have C1,1 regularity while classical methods require additional regularity and cannot be applied to all cases found in practice.
Soil gas geochemical exploration in covered terrains of northern Chile: data processing techniques and interpretation of contrast anomalies
Authors: Castillo Pamela I.C. , Townley Brian K. , Emery Xavier , Puig Álvaro F. , Deckart Katja
Published: April 2015

The Campanani, Casualidad and Inca de Oro prospects, owned by Codelco-Chile, are extensive areas covered by post-mineralization deposits. To assist the detection of potential exploration targets, we carried out basic soil gas sampling campaigns by means of the Ore Hound GOCC® passive collectors, which were buried on a regular grid at a depth of 30–40 cm. After 90–120 days, samples were retrieved, sealed, and adsorbent material was submitted to an acid elution and analysed by ICP-MS for a set of 72 elements. In this study, databases have been analysed and modelled by statistical and geostatistical methodologies, mainly by factorial kriging analysis (FK). In all cases, a systematic analytical error was detected, discriminated and filtered, allowing the definition of contrast anomalies at different scales of spatial variation, and the interpretation of evidence of secondary dispersion processes by which present time surface contrast anomalies have been developed.

The interpretation of contrast anomalies and element associations allowed the recognition of structural influences as pathways for gaseous circulation at the Campanani and Casualidad prospects. Likewise, lithological controls were detected at the Campanani and Inca de Oro prospects. At the Casualidad Prospect, a Co-Sn-Cu association describes a prospective zone
c
. 2 km north of the Casualidad deposit. At the Inca de Oro prospect, a marked influence of groundwater flow and/or surface drainage has been recognized in the configuration of contrast anomalies.
A new role for reticulon-4B/NOGO-B in the intestinal epithelial barrier function and inflammatory bowel disease
Authors: Rodríguez-Feo Juan Antonio , Puerto Marta , Fernández-Mena Carolina , Verdejo Cristina , Lara José Manuel , Díaz-Sánchez María , Álvarez Emilio , Vaquero Javier , Marín-Jiménez Ignacio , Bañares Rafael , Menchén Luis
Published: April 2015

Inflammatory bowel disease (IBD) is characterized by an impaired intestinal barrier function. We aimed to investigate the role of reticulon-4B (RTN-4B/NOGO-B), a structural protein of the endoplasmic reticulum, in intestinal barrier function and IBD. We used immunohistochemistry, confocal microscopy, real-time PCR, and Western blotting to study tissue distribution and expression levels of RTN-4B/NOGO-B in control and IBD samples from mouse and humans. We also targeted RTN-4B/NOGO-B using siRNAs in cultured human intestinal epithelial cell (IECs). Epithelial barrier permeability was assessed by transepithelial electrical resistance (TEER) measurement. RTN-4B/NOGO-B is expressed in the intestine mainly by IECs. Confocal microscopy revealed a colocalization of RTN-4B, E-cadherin, and polymerized actin fibers in tissue and cultured IECs. RTN-4B mRNA and protein expression were lower in the colon of IL-10−/− compared with wild-type mice. Colocalization of RTN-4B/E-cadherin/actin was reduced in the colon of IL-10−/− mice. Analysis of endoscopic biopsies from IBD patients showed a significant reduction of RTN-4B/NOGO-B expression in inflamed mucosa compared with control. Treatment of IECs with H2O2 reduced TEER values and triggered phosphorylation of RTN-4B in serine 107 residues as well as downregulation of RTN-4B expression. Acute RTN-4B/NOGO-B knockdown by siRNAs resulted in a decreased TEER values and reduction of E-cadherin and α-catenin expression and in the amount of F-actin-rich filaments in IECs. Epithelial RTN-4B/NOGO-B was downregulated in human and experimental IBD. RTN-4B participates in the intestinal epithelial barrier function, most likely via its involvement in E-cadherin, α-catenin expression, and actin cytoskeleton organization at sites of cell-to-cell contacts.
Duration of action of hypertonic saline on mucociliary clearance in the normal lung
Authors: Bennett W. D. , Wu J. , Fuller F. , Balcazar J. R. , Zeman K. L. , Duckworth H. , Donn K. H. , O'Riordan T. G. , Boucher R. C. , Donaldson S. H.
Published: April 2015

Inhalation of hypertonic saline (HS) acutely enhances mucociliary clearance (MC) in both health and disease. In patients with cystic fibrosis (CF), repeated use of HS causes a sustained improvement in MC as well as clinical benefit. The pharmacodynamic duration of activity on MC may be an important determinant of its therapeutic potential in other airways diseases. Before moving toward testing the clinical benefits of HS for non-CF indications, we sought to assess the duration of pharmacodynamic effects of HS in healthy subjects by performing radiotracer clearance studies at baseline, 30-min post-HS administration, and 4-h post-HS administration. Indeed, acceleration of MC was observed when measured 30 min after HS inhalation. This acceleration was most pronounced in the first 30 min after inhaling the radiotracer in the central lung region (mean Ave30Clr = 15.5 vs. 8.6% for 30-min post-HS treatment vs. mean baseline, respectively, P < 0.005), suggesting that acute HS effects were greatest in the larger bronchial airways. In contrast, when MC was measured 4 h after HS administration, all indices of central lung region MC were slower than at baseline: Ave30Clr = 5.9% vs. 8.6% ( P = 0.10); Ave90Clr = 12.4% vs. 16.8% ( P < 0.05); clearance through 3 h = 29.4 vs. 43.7% ( P < 0.002); and clearance through 6 h = 39.4 vs. 50.2% ( P < 0.02). This apparent slowing of MC in healthy subjects 4-h post-HS administration may reflect depletion of airway mucus following acute HS administration.
Plasma Lactate Levels Increase during Hyperinsulinemic Euglycemic Clamp and Oral Glucose Tolerance Test
Authors: Berhane Feven , Fite Alemu , Daboul Nour , Al-Janabi Wissam , Msallaty Zaher , Caruso Michael , Lewis Monique K. , Yi Zhengping , Diamond Michael P. , Abou-Samra Abdul-Badi , Seyoum Berhane
Published: April 2015

Insulin resistance, which plays a central role in the pathogenesis of type 2 diabetes (T2D), is an early indicator that heralds the occurrence of T2D. It is imperative to understand the metabolic changes that occur at the cellular level in the early stages of insulin resistance. The objective of this study was to determine the pattern of circulating lactate levels during oral glucose tolerance test (OGTT) and hyperinsulinemic euglycemic clamp (HIEC) study in normal nondiabetic subjects. Lactate and glycerol were determined every 30 minutes during OGTT and HIEC on 22 participants. Lactate progressively increased throughout the HIEC study period (P<0.001). Participants with BMI < 30 had significantly higher meanM-values compared to those with BMI ≥ 30 at baseline (P<0.05). This trend also continued throughout the OGTT. In addition, those with impaired glucose tolerance test (IGT) had significantly higher mean lactate levels compared to those with normal glucose tolerance (P<0.001). In conclusion, we found that lactate increased during HIEC study, which is a state of hyperinsulinemia similar to the metabolic milieu seen during the early stages in the development of T2D.
On the Relationship between Variational Level Set-Based and SOM-Based Active Contours
Authors: Abdelsamea Mohammed M. , Gnecco Giorgio , Gaber Mohamed Medhat , Elyan Eyad
Published: April 2015

Most Active Contour Models (ACMs) deal with the image segmentation problem as a functional optimization problem, as they work on dividing an image into several regions by optimizing a suitable functional. Among ACMs, variational level set methods have been used to build an active contour with the aim of modeling arbitrarily complex shapes. Moreover, they can handle also topological changes of the contours. Self-Organizing Maps (SOMs) have attracted the attention of many computer vision scientists, particularly in modeling an active contour based on the idea of utilizing the prototypes (weights) of a SOM to control the evolution of the contour. SOM-based models have been proposed in general with the aim of exploiting the specific ability of SOMs to learn the edge-map information via their topology preservation property and overcoming some drawbacks of other ACMs, such as trapping into local minima of the image energy functional to be minimized in such models. In this survey, we illustrate the main concepts of variational level set-based ACMs, SOM-based ACMs, and their relationship and review in a comprehensive fashion the development of their state-of-the-art models from a machine learning perspective, with a focus on their strengths and weaknesses.
Association of MRS-Based Vertebral Bone Marrow Fat Fraction with Bone Strength in a Human In Vitro Model
Authors: Karampinos Dimitrios C. , Ruschke Stefan , Gordijenko Olga , Grande Garcia Eduardo , Kooijman Hendrik , Burgkart Rainer , Rummeny Ernst J. , Bauer Jan S. , Baum Thomas
Published: April 2015

Bone marrow adiposity has recently gained attention due to its association with bone loss pathophysiology. In this study, ten vertebrae were harvested from fresh human cadavers. Trabecular BMD and microstructure parameters were extracted from MDCT. Bone marrow fat fractions were determined using single-voxel MRS. Failure load (FL) values were assessed by destructive biomechanical testing. Significant correlations (P<0.05) were observed between MRS-based fat fraction and MDCT-based parameters (up tor=-0.72) and MRS-based fat fraction and FL (r=-0.77). These findings underline the importance of the bone marrow in the pathophysiology and imaging diagnostics of osteoporosis.
1,25-Dihydroxyvitamin D3Promotes High Glucose-Induced M1 Macrophage Switching to M2 via the VDR-PPARγSignaling Pathway
Authors: Zhang Xiaoliang , Zhou Min , Guo Yinfeng , Song Zhixia , Liu Bicheng
Published: April 2015

Macrophages, especially their activation state, are closely related to the progression of diabetic nephropathy. Classically activated macrophages (M1) are proinflammatory effectors, while alternatively activated macrophages (M2) exhibit anti-inflammatory properties. 1,25-Dihydroxyvitamin D3has renoprotective roles that extend beyond the regulation of mineral metabolism, and PPARγ, a nuclear receptor, is essential for macrophage polarization. The present study investigates the effect of 1,25-dihydroxyvitamin D3on macrophage activation state and its underlying mechanism in RAW264.7 cells. We find that, under high glucose conditions, RAW264.7 macrophages tend to switch to the M1 phenotype, expressing higher iNOS and proinflammatory cytokines, including TNFαand IL-12. While 1,25-dihydroxyvitamin D3significantly inhibited M1 activation, it enhanced M2 macrophage activation; namely, it upregulated the expression of MR, Arg-1, and the anti-inflammatory cytokine IL-10 but downregulated the M1 markers. However, the above effects of 1,25-dihydroxyvitamin D3were abolished when the expression of VDR and PPARγwas inhibited by VDR siRNA and a PPARγantagonist. In addition, PPARγwas also decreased upon treatment with VDR siRNA. The above results demonstrate that active vitamin D promoted M1 phenotype switching to M2 via the VDR-PPARγpathway.
Modeling Spatiotemporal Precipitation: Effects of Density, Interpolation, and Land Use Distribution
Authors: Shope Christopher L. , Maharjan Ganga Ram
Published: April 2015

Characterization of precipitation is critical in quantifying distributed catchment-wide discharge. The gauge network is a key driver in hydrologic modeling to characterize discharge. The accuracy of precipitation is dependent on the location of stations, the density of the network, and the interpolation scheme. Our study examines 16 weather stations in a 64 km2catchment. We develop a weighted, distributed approach for gap-filling the observed meteorological dataset. We analyze five interpolation methods (Thiessen, IDW, nearest neighbor, spline, and ordinary Kriging) at five gauge densities. We utilize precipitation in a SWAT model to estimate discharge in lumped parameter simulations and in a distributed approach at the multiple densities (1, 16, 50, 142, and 300 stations). Gauge density has a substantial impact on distributed discharge and the optimal gauge density is between 50 and 142 stations. Our results also indicate that the IDW interpolation scheme was optimum, although the Kriging and Thiessen polygon methods produced similar results. To further examine variability in discharge, we characterized the land use and soil distribution throughout each of the subbasins. The optimal rain gauge position and distribution of the gauges drastically influence catchment-wide runoff. We found that it is best to locate the gauges near less permeable locations.
Derivation of Diagonally Implicit Block Backward Differentiation Formulas for Solving Stiff Initial Value Problems
Authors: Mohd Zawawi Iskandar Shah , Ibrahim Zarina Bibi , Othman Khairil Iskandar
Published: April 2015

The diagonally implicit 2-point block backward differentiation formulas (DI2BBDF) of order two, order three, and order four are derived for solving stiff initial value problems (IVPs). The stability properties of the derived methods are investigated. The implementation of the method using Newton iteration is also discussed. The performance of the proposed methods in terms of maximum error and computational time is compared with the fully implicit block backward differentiation formulas (FIBBDF) and fully implicit block extended backward differentiation formulas (FIBEBDF). The numerical results show that the proposed method outperformed both existing methods.
Optimal Sizing of a Photovoltaic-Hydrogen Power System for HALE Aircraft by means of Particle Swarm Optimization
Authors: Sanchez Victor M. , Barbosa Romeli , Cruz J. C. , Chan F. , Hernandez J.
Published: April 2015

Over the last decade there has been a growing interest in the research of feasibility to use high altitude long endurance (HALE) aircrafts in order to provide mobile communications. The use of HALEs for telecommunication networks has the potential to deliver a wide range of communication services (from high-quality voice to high-definition videos, as well as high-data-rate wireless channels) cost effectively. One of the main challenges of this technology is to design its power supply system, which must provide the enough energy for long time flights in a reliable way. In this paper a photovoltaic/hydrogen system is proposed as power system for a HALE aircraft due its high power density characteristic. In order to obtain the optimal sizing for photovoltaic/hydrogen system a particle swarm optimizer (PSO) is used. As a case study, theoretical design of the photovoltaic/hydrogen power system for three different HALE aircrafts located at 18° latitude is presented. At this latitude, the range of solar radiation intensity was from 310 to 450 Wh/sq·m/day. The results obtained show that the photovoltaic/hydrogen systems calculated by PSO can operate during one year with efficacies ranging between 45.82% and 47.81%. The obtained sizing result ensures that the photovoltaic/hydrogen system supplies adequate energy for HALE aircrafts.
Effects of Docosahexaenoic Supplementation andIn VitroVitamin C on the Oxidative and Inflammatory Neutrophil Response to Activation
Authors: Capó Xavier , Martorell Miquel , Sureda Antoni , Tur Josep Antoni , Pons Antoni
Published: April 2015

We studied the effects of diet supplementation with docosahexaenoic (DHA) andin vitrovitamin C (VitC) at physiological concentrations on oxidative and inflammatory neutrophil response to phorbol myristate acetate (PMA). Fifteen male footballers ingested a beverage enriched with DHA or a placebo for 8 weeks in a randomized double-blind study. Neutrophils were isolated from blood samples collected in basal conditions at the end of nutritional intervention. Neutrophils were cultured for 2 hours at 37°C in (a) control media, (b) media with PMA, and (c) media with PMA + VitC. PMA induces neutrophil degranulation with increased extracellular myeloperoxidase and catalase activities, nitric oxide production, expression of the inflammatory genes cyclooxygenase-2, nuclear factorκβ, interleukin 8 and tumor necrosis factorα, and interleukin 6 production. DHA diet supplementation boosts the exit of CAT from neutrophils but moderates the degranulation of myeloperoxidase granules induced by PMA. VitC facilitates azurophilic degranulation of neutrophils and increases gene expression of myeloperoxidase induced by PMA. VitC and DHA diet supplementation prevent PMA effects on inflammatory gene expression, although together they do not produce additional effects. DHA diet supplementation enhances antioxidant defences and anti-inflammatory neutrophil response toin vitroPMA activation. VitC facilitates neutrophil degranulation but prevents an inflammatory response to PMA.
Memory Dynamics in Attractor Networks
Authors: Li Guoqi , Ramanathan Kiruthika , Ning Ning , Shi Luping , Wen Changyun
Published: April 2015

As can be represented by neurons and their synaptic connections, attractor networks are widely believed to underlie biological memory systems and have been used extensively in recent years to model the storage and retrieval process of memory. In this paper, we propose a new energy function, which is nonnegative and attains zero values only at the desired memory patterns. An attractor network is designed based on the proposed energy function. It is shown that the desired memory patterns are stored as the stable equilibrium points of the attractor network. To retrieve a memory pattern, an initial stimulus input is presented to the network, and its states converge to one of stable equilibrium points. Consequently, the existence of the spurious points, that is, local maxima, saddle points, or other local minima which are undesired memory patterns, can be avoided. The simulation results show the effectiveness of the proposed method.
Phenotypic Characteristics Associated with Virulence of Clinical Isolates from theSporothrixComplex
Authors: Almeida-Paes Rodrigo , de Oliveira Luã Cardoso , Oliveira Manoel Marques Evangelista , Gutierrez-Galhardo Maria Clara , Nosanchuk Joshua Daniel , Zancopé-Oliveira Rosely Maria
Published: April 2015

TheSporothrixcomplex members cause sporotrichosis, a subcutaneous mycosis with a wide spectrum of clinical manifestations. Several specific phenotypic characteristics are associated with virulence in many fungi, but studies in this field involving theSporothrixcomplex species are scarce. Melanization, thermotolerance, and production of proteases, catalase, and urease were investigated in 61S. brasiliensis, oneS. globosa, and 10S. schenckiistrains. TheS. brasiliensisstrains showed a higher expression of melanin and urease compared withS. schenckii. These two species, however, presented similar thermotolerances. OurS. globosastrain had low expression of all studied virulence factors. The relationship between these phenotypes and clinical aspects of sporotrichosis was also evaluated. Strains isolated from patients with spontaneous regression of infection were heavily melanized and produced high urease levels. Melanin was also related to dissemination of internal organs and protease production was associated with HIV-coinfection. A murine sporotrichosis model showed that aS. brasiliensisstrain with high expression of virulence factors was able to disseminate and yield a high fungal burden in comparison with a controlS. schenckiistrain. Our results show that virulence-related phenotypes are variably expressed within theSporothrixcomplex species and might be involved in clinical aspects of sporotrichosis.
Application of FTIR-ATR Spectroscopy to Determine the Extent of Lipid Peroxidation in Plasma during Haemodialysis
Authors: Oleszko Adam , Olsztyńska-Janus Sylwia , Walski Tomasz , Grzeszczuk-Kuć Karolina , Bujok Jolanta , Gałecka Katarzyna , Czerski Albert , Witkiewicz Wojciech , Komorowska Małgorzata
Published: April 2015

During a haemodialysis (HD), because of the contact of blood with the surface of the dialyser, the immune system becomes activated and reactive oxygen species (ROS) are released into plasma. Particularly exposed to the ROS are lipids and proteins contained in plasma, which undergo peroxidation. The main breakdown product of oxidized lipids is the malondialdehyde (MDA). A common method for measuring the concentration of MDA is a thiobarbituric acid reactive substances (TBARS) method. Despite the formation of MDA in plasma during HD, its concentration decreases because it is removed from the blood in the dialyser. Therefore, this research proposes the Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR) spectroscopy, which enables determination of primary peroxidation products. We examined the influence of the amount of hydrogen peroxide added to lipid suspension that was earlier extracted from plasma specimen on lipid peroxidation with use of TBARS and FTIR-ATR methods. Linear correlation between these methods was shown. The proposed method was effective during the evaluation of changes in the extent of lipid peroxidation in plasma during a haemodialysis in sheep. A measurement using the FTIR-ATR showed an increase in plasma lipid peroxidation after 15 and 240 minutes of treatment, while the TBARS concentration was respectively lower.
Impacts of the Two Biggest Lakes on Local Temperature and Precipitation in the Yellow River Source Region of the Tibetan Plateau
Authors: Wen Lijuan , Lv Shihua , Li Zhaoguo , Zhao Lin , Nagabhatla Nidhi
Published: April 2015

The Tibetan Plateau harbors thousands of lakes; however few studies focus on impacts of lakes on local climate in the region. To investigate and quantify impacts of the two biggest lakes (Ngoring Lake and Gyaring Lake) of the Yellow River source region in the Tibetan Plateau on local climate, two simulations (with and without the two large lakes) from May 2010 to July 2011 are performed and analyzed using the WRF-CLM model (the weather research and forecasting model coupled with the community land model). Differences between simulated results show that the WRF-CLM model could provide realistic reproduction of surface observations and has better simulation after considering lakes. Lakes mostly reduce the maximum temperature all year round and increase the minimum temperature except in March due to the large heat capacity that makes lakes absorb (release) more energy for the same temperature change compared to land. Lakes increase precipitation over the lake area and in the nearby region, mostly during 02–14 BT (Beijing Time) of July to October when the warm lake surface induces the low level horizontal convergence and updraft over lake and provides energy and vapor to benefit the development of the convection for precipitation.
Thickness Mapping of Eleven Retinal Layers Segmented Using the Diffusion Maps Method in Normal Eyes
Authors: Kafieh Raheleh , Rabbani Hossein , Hajizadeh Fedra , Abramoff Michael D. , Sonka Milan
Published: April 2015

This study was conducted to determine the thickness map of eleven retinal layers in normal subjects by spectral domain optical coherence tomography (SD-OCT) and evaluate their association with sex and age. Mean regional retinal thickness of 11 retinal layers was obtained by automatic three-dimensional diffusion map based method in 112 normal eyes of 76 Iranian subjects. We applied our previously reported 3D intraretinal fast layer segmentation which does not require edge-based image information but rather relies on regional image texture. The thickness maps are compared among 9 macular sectors within 3 concentric circles as defined by ETDRS. The thickness map of central foveal area in layers 1, 3, and 4 displayed the minimum thickness. Maximum thickness was observed in nasal to the fovea of layer 1 and in a circular pattern in the parafoveal retinal area of layers 2, 3, and 4 and in central foveal area of layer 6. Temporal and inferior quadrants of the total retinal thickness and most of other quadrants of layer 1 were significantly greater in the men than in the women. Surrounding eight sectors of total retinal thickness and a limited number of sectors in layers 1 and 4 significantly correlated with age.
Model Predictive Control of NCS with Data Quantization and Bounded Arbitrary Time Delays
Authors: Yu Jimin , Xie Yanan , Tang Xiaoming
Published: April 2015

The model predictive control for constrained discrete time linear system under network environment is considered. The bounded time delay and data quantization are assumed to coexist in the data transmission link from the sensor to the controller. A novel NCS model is specially established for the model predictive control method, which casts the time delay and data quantization into a unified framework. A stability result of the obtained closed-loop model is presented by applying the Lyapunov method, which plays a key role in synthesizing the model predictive controller. The model predictive controller, which parameterizes the infinite horizon control moves into a single state feedback law, is provided which explicitly considers the satisfaction of input and state constraints. Two numerical examples are given to illustrate the effectiveness of the derived method.
Activins and Follistatin in Chronic Hepatitis C and Its Treatment with Pegylated‐Interferon‐α Based Therapy
Authors: Refaat Bassem , Ashshi Ahmed Mohamed , El-Shemi Adel Galal , Azhar Esam
Published: April 2015

Pegylated‐interferon‐α based therapy for the treatment of chronic hepatitis C (CHC) is considered suboptimal as not all patients respond to the treatment and it is associated with several side effects that could lead to dose reduction and/or termination of therapy. The currently used markers to monitor the response to treatment are based on viral kinetics and their performance in the prediction of treatment outcome is moderate and does not combine accuracy and their values have several limitations. Hence, the development of new sensitive and specific predictor markers could provide a useful tool for the clinicians and healthcare providers, especially in the new era of interferon‐free therapy, for the classification of patients according to their response to the standard therapy and only subscribing the novel directly acting antiviral drugs to those who are anticipated not to respond to the conventional therapy and/or have absolute contraindications for its use.
The importance of activins and follistatin in the regulation of immune system, liver biology, and pathology has recently emerged. This review appraises the up‐to‐date knowledge regarding the role of activins and follistatin in liver biology and immune system and their role in the pathophysiology of CHC.