bluuebunny/crossref_metadata_2025 huggingface dataset:
Sulfur/Alkali/Calcium Oxide Sorbent Interaction in Pressurized Coal Combustors
Authors: Garman Andrew R. , Boni Arthur A. , Campbell John P. , Simons Girard A. , Johnson Stephen A.
Published: March 2015

Modeling and bench-scale experiments have been performed related to the capture of fuel-bound sulfur by calcium-based sorbents injected into pressurized coal combustors. Sorbent types tested include two limestones, a dolomite, a slaked lime, and a pressure-hydrated dolomite, with and without several sodium-based mineral promoters present. Sulfur capture data have been obtained at pressures up to 10 atm. These data have been incorporated into the porous sorbent model of Simons and Garman (6). Modeling of lean turbine combustors indicates that in-situ injection of pressure-hydrated sorbents should remove greater than 50 percent of the SO2 at 10 atm and 0.5 sec residence time. Furthermore the presence of alkali minerals in the coal can enhance the intrinsic reactivity by a factor of two or more. Conveniently, the calcium sorbent can serve as a site for alkali condensation and removal.
Wetness and Efficiency Measurements in L.P. Turbines With an Optical Probe as an Aid to Improving Performance
Authors: Walters P. T.
Published: March 2015

An absolute value for the wetness fraction in a partially condensed steam flow may be calculated from measurements of light transmission using the results of fundamental electromagnetic scattering theory. A probe is described that uses this principle for measuring radial wetness profiles in the final stages of L.P. turbines. Results are presented to show that the probe will provide reliable values for overall L.P. turbine efficiency and valuable diagnostic data on the performance of individual stages operating with wet or condensing flows.
Preliminary Engineering for a 50 MW Compressed Air Energy Storage Plant for Alabama Electric Cooperative, Inc.
Authors: Clausen B. R. , Nakhamkin M. , Swensen E. C.
Published: March 2015

This paper presents preliminary engineering results for a 50 MW Compressed Air Energy Storage (CAES) plant for the Alabama Electric Cooperative, Inc. (AEC). The CAES plant would improve AEC’s power generation mix in two ways: (a) it would provide needed peaking/intermediate power (otherwise purchased) and (b) it would increase the load factor of economical baseload units.

The paper presents the following:

a. Comparative trade-off analysis of various conceptual arrangements with underground storage depths ranging between 1000 feet and 4000 feet. (The most economical concept is selected based on the consideration of economics of the overall plant including underground storage).

b. Engineering and cost data, performance data, construction schedule and environmental data for the selected CAES plant concept.

The results of this preliminary engineering effort prove that a CAES plant is a cost effective addition to AEC’s installed power generation plants.
Circulating Fluidized Bed Combustor Utilization With Compressed Air Energy Storage Plants
Authors: Nakhamkin Michael , Stange John R. , Duttenhoffer Richard , Pelini Robert , Schainker Robert B.
Published: March 2015

This paper presents results of engineering of a Circulating Fluidized Bed Combustor (CFBC) for Compressed Air Energy Storage (CAES) application. This development allows eliminating the use of premium fuels thus resolving economic as well as institutional issues.

The paper summarizes the engineering, performance and cost data for a CFBC and presents comparative technical and economic analyses of a CAES plant with CFBC (burning coal) versus a conventional CAES plant (burning premium fuel).
Closed Circuit Steam Cooling in Gas Turbines
Authors: Alderson E. D. , Scheper G. W. , Cohn A.
Published: March 2015

In the continuing effort to achieve better specific power and higher cycle efficiencies, gas turbine designers have through the years sought higher and higher firing temperatures. A large part of this gain in firing temperatures has been achieved through cooling the turbine nozzles and buckets. In almost all cases the coolant, usually air, is discharged into the gas path after performing its cooling function. This approach entails the double penalties of causing mixing losses and of producing a dilution of the hot gas stream by admixture of the lower temperature coolant.

This paper presents a new cooling concept, developed under a study contract for Electric Power Research Institute, wherein high pressure steam is used as the coolant in a closed circuit steam cooling (CCSC) system. This not only avoids the mixing and dilution losses in the gas turbine, but permits recovery of the heat picked up in the coolant by expansion in a steam turbine. With CCSC, Brayton-combined cycle thermal efficiencies of 54% are projected using current materials and technology. With development of specific technologies, an ultimate efficiency for the Brayton-combined cycle of 57% is foreseen. This paper also discusses the sensitivity of the cycle performance to the design parameters. Performance of this CCSC cycle is compared to that of an advanced air-cooled Brayton combined cycle.
Operating Experience Complements New Technology in Design of Advanced Combustion Turbine
Authors: Scalzo A. J. , Antos R. J. , Fukue I.
Published: March 2015

High reliability and availability of current production combustion turbines have been achieved only after the identification and the resolution of past operating anomilies. Technological advances in fields such as aerodynamics, metallurgy, cooling, and computer capability have played important roles in these solutions as well as in the development of new advanced heavy duty combustion turbines. This paper discusses experiences with the W501 and the MW 701D combustion turbines and how this background influenced the design of the 501F advanced heavy duty combustion turbine.
Feasibility Study of the Modernization and Upgrade of a Combined Cycle Power Plant
Authors: Madison Mike , Snow Ben , Allison Perry , Schweikhard Wayne
Published: March 2015

The 220MW Public Service of Oklahoma Comanche Station PACE (Power at Combined Efficiency) combined cycle power plant located in Lawton, Oklahoma underwent a major upgrade and life extension during 1985–1986. Prior to committing the project, an extensive study was performed to quantify and evaluate the effects of the project on the PSO system and its impact on PSO’s long-term goal of providing quality, economical service to its customers. This paper presents techniques used to assess these effects (generically) on a utility system and determine the benefits to both consumers and investors. This information is presented in such a form that it may be used as a guide to perform similar studies of plant upgrades and modernizations.
The First 200 MWGAS Turbine Ordered in the World
Authors: Darthenay A. , Gardelle T. , Hoisnard C. , Drame V.
Published: March 2015

The French generation mix is characterized by a great number of nuclear power plants.
Advanced Particle Control for Coal-Based Power Generation Systems
Authors: Bossart Steven J.
Published: March 2015

The Morgantown Energy Technology Center (METC) of the U.S. Department of Energy (DOE) is actively sponsoring research to develop coal-based power generation systems that use coal more efficiently and economically and with lower emissions than conventional pulverized-coal power plants. Some of the more promising of the advanced coal-based power generation systems are shown in Figure 1: pressurized fluidized-bed combustion combined-cycle (PFBC), integrated gasification combined-cycle (IGCC), and direct coal-fueled turbine (DCFT). These systems rely on gas turbines to produce all or a portion of the electrical power generation. An essential feature of each of these systems is the control of particles at high-temperature and high-pressure (HTHP) conditions. Particle control is needed in all advanced power generation systems to meet environmental regulations and to protect the gas turbine and other major system components. Particles can play a significant role in damaging the gas turbine by erosion, deposition, and corrosion. Erosion is caused by the high-speed impaction of particles on the turbine blades. Particle deposition on the turbine blades can impede gas flow and block cooling air. Particle deposition also contributes to corrosive attack when alkali metal compounds adsorbed on the particles react with the gas turbine blades. Incorporation of HTHP particle control technologies into the advanced power generation systems can reduce gas turbine maintenance requirements, increase plant efficiency, reduce plant capital cost, lower the cost of electricity, reduce wastewater treatment requirements, and eliminate the need for post-turbine particle control to meet New Source Performance Standards (NSPS) for particle emissions.
An investigation into factors affecting the precision of CT radiation dose profile width measurements using radiochromic films
Authors: Li Baojun , Behrman Richard H.
Published: March 2015

Purpose:

To investigate the impact of x‐ray beam energy, exposure intensity, and flat‐bed scanner uniformity and spatial resolution on the precision of computed tomography (CT) beam width measurements using Gafchromic XR‐QA2 film and an off‐the‐shelf document scanner.

Methods:

Small strips of Gafchromic film were placed at isocenter in a CT scanner and exposed at various x‐ray beam energies (80–140 kVp), exposure levels (50–400 mA s), and nominal beam widths (1.25, 5, and 10 mm). The films were scanned in reflection mode on a Ricoh MP3501 flat‐bed document scanner using several spatial resolution settings (100 to 400 dpi) and at different locations on the scanner bed. Reflection measurements were captured in digital image files and radiation dose profiles generated by converting the image pixel values to air kerma through film calibration. Beam widths were characterized by full width at half maximum (FWHM) and full width at tenth maximum (FWTM) of dose profiles. Dependences of these parameters on the above factors were quantified in percentage change from the baselines.

Results:

The uncertainties in both FWHM and FWTM caused by varying beam energy, exposure level, and scanner uniformity were all within 4.5% and 7.6%, respectively. Increasing scanner spatial resolution significantly increased the uncertainty in both FWHM and FWTM, with FWTM affected by almost 8 times more than FWHM (48.7% vs 6.5%). When uncalibrated dose profiles were used, FWHM and FWTM were over‐estimated by 11.6% and 7.6%, respectively. Narrower beam width appeared more sensitive to the film calibration than the wider ones (R2 = 0.68 and 0.85 for FWHM and FWTM, respectively). The global and maximum local background variations of the document scanner were 1.2%. The intrinsic film nonuniformity for an unexposed film was 0.3%.

Conclusions:

Measurement of CT beam widths using Gafchromic XR‐QA2 films is robust against x‐ray energy, exposure level, and scanner uniformity. With proper film calibration and scanner resolution setting, it can provide adequate precision for meeting ACR and manufacturer's tolerances for the measurement of CT dose profiles.
Getting the Lorentz transformations without requiring an invariant speed
Authors: Pelissetto Andrea , Testa Massimo
Published: March 2015

The structure of the Lorentz transformations follows purely from the absence of privileged inertial reference frames and the group structure (closure under composition) of the transformations—two assumptions that are simple and physically necessary. The existence of an invariant speed is not a necessary assumption and in fact is a consequence of the principle of relativity (though the finite value of this speed must, of course, be obtained from experiment). Von Ignatowsky derived this result in 1911, but it is still not widely known and is absent from most textbooks. Here, we present a completely elementary proof of the result, suitable for use in an introductory course in special relativity.
A truly elementary proof of Bertrand's theorem
Authors: Chin Siu A.
Published: March 2015

An elementary proof of Bertrand's theorem is given by examining the radial orbit equation, without needing to solve complicated equations or integrals.
Dimensional analysis as the other language of physics
Authors: Robinett R. W.
Published: March 2015

We review the use of dimensional analysis as a tool for the systematic study and analysis of physical concepts and phenomena at multiple levels in the physics curriculum. After reviewing the methodology of its use and citing examples from classical physics, we illustrate how it can be applied to problems in quantum mechanics, including research-level problems, noting both its power and its limitations.
Unveiling the physics of the Thomson jumping ring
Authors: Ladera Celso L. , Donoso Guillermo
Published: March 2015

We present a new theoretical model and validating experiments that unveil the rich physics behind the flight of the conductive ring in the Thomson experiment—physics that is hard to see because of the rapid motion. The electrodynamics of the flying ring exhibits interesting features, e.g., varying mutual inductance between the ring and the electromagnet. The dependences of the ring electrodynamics upon time and position as the ring travels upward are conveniently separated and determined to obtain a comprehensive view of the ring motion. We introduce a low-cost jumping ring setup that incorporates pickup coils connected in opposition, allowing us to scrutinize the ring electrodynamics and confirm our theoretical model with good accuracy. This work is within the reach of senior students of science or engineering, and it can be implemented either as a teaching laboratory experiment or as an open-ended project.
Molecular nitrogen in comet 67P/Churyumov-Gerasimenko indicates a low formation temperature
Authors: Rubin M. , Altwegg K. , Balsiger H. , Bar-Nun A. , Berthelier J.-J. , Bieler A. , Bochsler P. , Briois C. , Calmonte U. , Combi M. , De Keyser J. , Dhooghe F. , Eberhardt P. , Fiethe B. , Fuselier S. A. , Gasc S. , Gombosi T. I. , Hansen K. C. , Hässig M. , Jäckel A. , Kopp E. , Korth A. , Le Roy L. , Mall U. , Marty B. , Mousis O. , Owen T. , Rème H. , Sémon T. , Tzou C.-Y. , Waite J. H. , Wurz P.
Published: March 2015

Making comets in the cold

The speciation of nitrogen compounds in comets can tell us about their history. Comets are some of the most ancient bodies in the solar system and should contain the nitrogen compounds that were abundant when they formed. Using the ROSINA mass spectrometer aboard the Rosetta spacecraft orbiting comet 67P/Churyumov-Gerasimenko, Rubin
et al.
found molecular nitrogen at levels that are depleted compared to those in the primordial solar system. Depletion of such a magnitude suggests that the comet formed either from the low-temperature agglomeration of pristine amorphous water ice grains or from clathrates.

Science
, this issue p.
232
Regulatory T cells generated early in life play a distinct role in maintaining self-tolerance
Authors: Yang Siyoung , Fujikado Noriyuki , Kolodin Dmitriy , Benoist Christophe , Mathis Diane
Published: March 2015

Early T cells keep autoimmunity at bay

A major challenge faced by the immune system is to react to foreign substances, such as microbes, while simultaneously tolerating the self. Upsetting this balance leads to autoimmunity. Regulatory T cells (T
regs
), are a subset of immune cells that help to maintain this balance. Yang
et al.
found that murine T
reg
cells generated very early in life are distinct from those generated in older animals and play an especially important role in keeping autoimmunity in check (see the Perspective by Tanaka and Sakaguchi). These changes are due to differences in the way T
regs
develop in the thymus in newborn versus adult mice.

Science
, this issue p.
589
; see also p.
506
Genome Sequence of Bivens Arm Virus, a Tibrovirus Belonging to the Species Tibrogargan virus (
Mononegavirales
:
Rhabdoviridae
)
Authors: Lauck Michael , Yú Shuǐqìng , Caì Yíngyún , Hensley Lisa E. , Chiu Charles Y. , O’Connor David H. , Kuhn Jens H.
Published: March 2015

The new rhabdoviral genus
Tibrovirus
currently has two members, Coastal Plains virus and Tibrogargan virus. Here, we report the coding-complete genome sequence of a putative member of this genus, Bivens Arm virus. A genomic comparison reveals Bivens Arm virus to be closely related to, but distinct from, Tibrogargan virus.
Complete Genome Sequence of Terribacillus aidingensis Strain MP602, a Moderately Halophilic Bacterium Isolated from Cryptomeria fortunei in Tianmu Mountain in China
Authors: Lu Peng , Lei Mengying , Xiao Fenghu , Zhang Liqin , Wang Yongjun
Published: March 2015

Terribacillus aidingensis
strain MP602, which was isolated from an ancient tree (Cryptomeria forunei) in Tianmu Mountain in China, has antagonistic activity against several certain phytopathogenic fungi. Here, we report the genome sequence of this strain. This is the first complete genome report of the Terribacillus genus.
Complete Genome Sequence of Halophilic Yeast
Meyerozyma caribbica
MG20W Isolated from Rhizosphere Soil
Authors: Kim Jong-Shik , Baek Jeong-Hoon , Park Nyun-Ho , Kim Changhoon
Published: March 2015

Meyerozyma caribbica MG20W was originally isolated from rhizosphere soil on reclaimed land in the Republic of Korea. We describe herein the 10.64-Mbp-long genome sequence of M. caribbica MG20W, which exhibits high salt resistance.
Draft Genome Sequence of the Polychlorinated Biphenyl-Degrading Bacterium Cupriavidus basilensis KF708 (NBRC 110671) Isolated from Biphenyl-Contaminated Soil
Authors: Suenaga Hikaru , Yamazoe Atsushi , Hosoyama Akira , Kimura Nobutada , Hirose Jun , Watanabe Takahito , Fujihara Hidehiko , Futagami Taiki , Goto Masatoshi , Furukawa Kensuke
Published: March 2015

We report the draft genome sequence of
Cupriavidus basilensis
KF708 (NBRC 110671), which utilizes biphenyl as a sole carbon source and degrades polychlorinated biphenyls (PCBs). The KF708 strain possesses genes for biphenyl catabolism and other genes involved in various aromatic compounds.
Draft Genome Sequence of Xanthomonas sacchari Strain LMG 476
Authors: Pieretti Isabelle , Bolot Stéphanie , Carrère Sébastien , Barbe Valérie , Cociancich Stéphane , Rott Philippe , Royer Monique
Published: March 2015

We report the high-quality draft genome sequence of
Xanthomonas sacchari
strain LMG 476, isolated from sugarcane. The genome comparison of this strain with a previously sequenced X. sacchari strain isolated from a distinct environmental source should provide further insights into the adaptation of this species to different habitats and its evolution.
Cognitive dysfunction in adolescents with chronic fatigue: a cross-sectional study
Authors: Sulheim Dag , Fagermoen Even , Sivertsen Øyvind Stople , Winger Anette , Wyller Vegard Bruun , Øie Merete Glenne
Published: March 2015

Objective

To compare cognitive function in adolescents with chronic fatigue with cognitive function in healthy controls (HC).

Study design

Cross-sectional study.

Setting

Paediatric department at Oslo University Hospital, Norway.

Participants

120 adolescents with chronic fatigue (average age 15.4 years; range 12–18) and 39 HC (average age 15.2 years; range 12–18).

Methods

The adolescents completed a neurocognitive test battery measuring processing speed, working memory, cognitive inhibition, cognitive flexibility, verbal learning and verbal memory, and questionnaires addressing demographic data, depression symptoms, anxiety traits, fatigue and sleep problems. Parents completed the Behaviour Rating Inventory of Executive Function (BRIEF), which measures the everyday executive functions of children.

Results

Adolescents with chronic fatigue had impaired cognitive function compared to HC regarding processing speed (mean difference 3.3, 95% CI 1.1 to 5.5, p=0.003), working memory (−2.4, −3.7 to −1.1, p<0.001), cognitive inhibition response time (6.2, 0.8 to 11.7, p=0.025) and verbal learning (−1.7, −3.2 to −0.3, p=0.022). The BRIEF results indicated that everyday executive functions were significantly worse in the chronic fatigue group compared to the HC (11.2, 8.2 to 14.3, p<0.001). Group differences remained largely unaffected when adjusted for symptoms of depression, anxiety traits and sleep problems.

Conclusions

Adolescents with chronic fatigue had impaired cognitive function of clinical relevance, measured by objective cognitive tests, in comparison to HC. Working memory and processing speed may represent core difficulties.
What makes for a ‘good’ or ‘bad’ paediatric diabetes service from the viewpoint of children, young people, carers and clinicians? A synthesis of qualitative findings
Authors: Curtis-Tyler Katherine , Arai Lisa , Stephenson Terence , Roberts Helen
Published: March 2015

Background

There is mounting evidence that experience of care is a crucial part of the pathway for successful management of long-term conditions.

Design and objectives

To carry out (1) a systematic mapping of qualitative evidence to inform selection of studies for the second stage of the review; and (2) a narrative synthesis addressing the question, What makes for a ‘good’ or a ‘bad’ paediatric diabetes service from the viewpoint of children, young people, carers and clinicians?

Results

The initial mapping identified 38 papers. From these, the findings of 20 diabetes-focused papers on the views on care of ≥650 children, parents and clinicians were synthesised. Only five studies included children under 11 years. Children and young people across all age groups valued positive, non-judgemental and relationship-based care that engaged with their social, as well as physical, health. Parents valued provision responsive to the circumstances of family life and coordinated across services. Clinicians wanting to engage with families beyond a child's immediate physical health described finding this hard to achieve in practice.

Limitations

Socioeconomic status and ethnicity were poorly reported in the included studies.

Conclusions

In dealing with diabetes, and engaging with social health in a way valued by children, parents and clinicians, not only structural change, such as more time for consultation, but new skills for reworking relations in the consultation may be required.
A rare case of bilateral nasolabial cysts
Authors: Sethukumar Priya , Taghi Ali , Kuchai Romana
Published: March 2015

Nasolabial cysts are rare non-odontogenic cystic lesions representing around 0.7% of all maxillofacial cysts. They usually present as unilateral painless swellings, sometimes with epiphora and dacryocystitis as well as pain in cases of rapid growth or infection. We have reviewed the literature and present an extremely rare case of bilateral nasolabial cysts in a young Afro-Caribbean man presenting with chronic nasal blockage, epiphora and rhinorrhoea. We describe our successful surgical management using a sublabial approach for complete excision, leading to a disease-free outcome at 6 months follow-up. Other modalities have been described, from endoscopic marsupialisation to simple aspiration. However, with the exception of complete surgical excision, all other surgical techniques are associated with a high recurrence rate. We therefore advocate complete surgical excision as described below for optimal results.
The trumpet player with a swelling in the neck
Authors: Edmiston Rachel , Hariri Ahmad , Karagama Yakubu
Published: March 2015

Bilateral neck swelling in patients following valsalva manouveres could lead to a diagnosis of either a pharyngocele or laryngocele. Distinguishing between them can be complicated but is vital given the possibility for an acute airway in patients with laryngoceles.

A 20-year-old trumpet player presents with a 5-year history of neck swelling. Clinical suspicion is that of a pharyngocele but imaging introduces some confusion with the diagnosis.

Both pharyngoceles and laryngoceles can occur as a result of prolonged positive pressure. Accurate assessment with fibreoptic examination and imaging is needed to confirm the diagnosis.

Pharyngoceles are often misdiagnosed as laryngoceles. Though treatment is similar between the two patient groups it is vital that a distinction is made to enable careful observation of the airway in patients with laryngoceles.
Race/ethnicity and the risk of childhood leukaemia: a case–control study in California
Authors: Oksuzyan Sona , Crespi Catherine M , Cockburn Myles , Mezei Gabor , Vergara Ximena , Kheifets Leeka
Published: March 2015

Background

We conducted a large registry-based study in California to investigate the association between race/ethnicity and childhood leukaemia focusing on two subtypes: acute lymphoblastic leukaemia (ALL) and acute myeloid leukaemia (AML).

Methods

We obtained information on 5788 cases and 5788 controls by linking California cancer and birth registries. We evaluated relative risk of childhood leukaemia by race and ethnicity of the child and their parents using conditional logistic regression, with adjustment for potential confounders.

Results

Compared with Whites, Black children had lower risk of ALL (OR=0.54, 95% CI 0.45 to 0.66) as well as children of Black/Asian parents (OR=0.31, 95% CI 0.10 to 0.94). Asian race was associated with increased risk of AML with OR=1.643, 95% CI 1.10 to 2.46 for Asian vs Whites; and OR=1.67, 95% CI 1.04 to 2.70 for Asian/Asian vs White/White. Hispanic ethnicity was associated with increased risk of ALL (OR=1.37, 95% CI 1.22 to 1.52). A gradient in risk of ALL was observed while comparing Hispanic children with both parents Hispanic, one parent Hispanic and non-Hispanic children (p Value for trend <0.0001). The highest risk of ALL was observed for children with a combination of Hispanic ethnicity and White race compared with non-Hispanic whites (OR=1.27, 95% CI 1.12 to 1.44). The lowest risk was observed for non-Hispanic blacks (OR=0.46, 95% CI 0.36 to 0.60). Associations for total childhood leukaemia were similar to ALL.

Conclusions

Our results confirm that there are ethnic and racial differences in the incidence of childhood leukaemia. These differences indicate that some genetic and/or environmental/cultural factors are involved in aetiology of childhood leukaemia.
THE BRITISH KNOCK-OUT PUT OPTION
Authors: AL-FAGIH LULUWAH
Published: March 2015

Following the economic rationale introduced by Peskir & Samee (2011, 2013) we present a new class of barrier options within the British payoff mechanism where the holder enjoys the early exercise feature of American type options whereupon his payoff (deliverable immediately) is the best prediction of the European payoff under the hypothesis that the true drift of the stock price equals a contract drift. Should the option holder believe the true drift of the stock price to be unfavorable (based upon the observed price movements) he can substitute the true drift with the contract drift and minimize his losses. In this paper, we focus on the knock-out put option with an up barrier. We derive a closed form expression for the arbitrage-free price in terms of the rational exercise boundary and show that the rational exercise boundary itself can be characterized as the unique solution to a nonlinear integral equation. Using these results, we perform a financial analysis of the British knock-out put option. We spot some of the trends previously seen in Peskir & Samee (2011) but observe some behavior unique to the knock-out case. Finally, we derive the British put-call and up-down symmetry relations which express the arbitrage-free price and the rational exercise boundary of the British down-and-out call option in terms of the arbitrage-free price and the rational exercise boundary of the British up-and-out put option.
PEDICLE SCREW CONVERGENCE IMPACT ON THE STABILITY OF TRANSPEDICULAR FIXATION SPINE MODEL IN CYCLIC LOADING: BIOMECHANICAL STUDY
Authors: VCELAK JOSEF , TICHÝ PETR , BOUDA TOMÁŠ , CHOMIAK JIŘÍ , TÓTH LADISLAV
Published: March 2015

The principle of this study is experimental measurement and description of behavior of transpedicular fixation during cyclic loading due to convergence of screw insertion. Investigations were made of three configurations of assemblies of posterior stabliization with converging screws at 0°, 20° and 40°. The experiment was inspired ASTM Standard F1717 and modified to minimize the effect of other parameters. The MTS 858.2 Mini Bionix testing system was used during the experiment, in conjunction with the Interface 1010ACK load cell. Data processing and analysis were carried out by Matlab R 20102b, MathWorks. The probed assemblies were cyclically loaded until structural failure occurred, always at the screwbone (or PUR block) interface, i.e., the "windshield wiper" effect. The measurement results show that while the rigidity of the assembly increases with increased convergence of transpedicular screws, they also indicate an increased initial rate of assembly damage accumulation, together with assembly failure during a reduced number of cyclic loading cycles. The mechanical behavioral study of transpedicular fixation is limited by the conditions of simplification of interpretation of complex movements and spinal pathophysiology in the attempt to minimize the effect of other parameters and exaggerated measurements.
SIMILARITIES OF SUCCESSFUL TECHNOLOGY TRANSFER THROUGH NEW VENTURES
Authors: FESTEL GUNTER
Published: March 2015

Especially established industries, like the chemical and pharmaceutical industry, rely on effective and efficient technology transfer to maintain their competitiveness. Academic spin-offs, corporate spin-outs, and internal start-ups, as different types of new ventures, can be used for technology transfer from universities and research institutions to companies as well as between or within companies. Especially internal start-ups are a new approach for company internal technology transfer from research departments to business units. Based on 12 case studies from the chemical and pharmaceutical industry in Germany and Switzerland, which were identified and developed by narrative interviews with new ventures and parent organisations, like companies, universities, and research institutions, technology transfer through new ventures has been analysed. Despite the various backgrounds and challenges, the different types of new ventures show much more similarities than dissimilarities. Therefore, learnings from academic spin-offs can be transferred to corporate spin-outs and internal start-ups in the context of technology transfer.
Aerobic physical training increases contractile response and reduces cardiac fibrosis in rats subjected to early ovarian hormone deprivation
Authors: Felix Ana Carolina S. , Dutra Sabrina G. V. , Tezini Geisa C. S. V. , Simões Marcus Vinicius , de Souza Hugo Celso Dutra
Published: March 2015

We investigated the effects of early ovarian hormone deprivation on the heart and the role of physical training in this condition using different approaches: cardiac autonomic tone, contractility, morphology and function, and cardiac fibrosis. Female Wistar rats ( n = 48) were assigned into two groups: ovariectomized (Ovx; 10-wk-old) and control rats (Sham; 10-wk-old). Each group was further divided into two subgroups, sedentary and trained (aerobic training by swimming for 10 wk). The sedentary groups showed similar cardiac autonomic tone values; however, only the Sham group had an increase in vagal participation for the determination of the basal heart rate after physical training. The contractile responses to cardiac β-agonists of the sedentary groups were similar, including an increased response to a β1-agonist (dobutamine) observed after physical training. The Ovx sedentary group presented changes in cardiac morphology, which resulted in decreases in the ejection fraction, fractional shortening, and cardiac index compared with the Sham sedentary group. Physical training did little to alter these findings. Moreover, histology analysis showed a significant increase in cardiac fibrosis in the sedentary Ovx group, which was not observed in the trained Ovx group. We conclude that early ovarian hormone deprivation in rats impairs autonomic control, cardiac morphology, and cardiac function and increases cardiac fibrosis; however, it does not affect the contractility induced by dobutamine and salbutamol. Furthermore, this model of physical training prevented an increase in fibrosis and promoted an increase in the cardiac contractile response but had little effect on cardiac autonomic control or morphological and functional parameters.
The Date Palm Tree Rhizosphere Is a Niche for Plant Growth Promoting Bacteria in the Oasis Ecosystem
Authors: Ferjani Raoudha , Marasco Ramona , Rolli Eleonora , Cherif Hanene , Cherif Ameur , Gtari Maher , Boudabous Abdellatif , Daffonchio Daniele , Ouzari Hadda-Imene
Published: March 2015

In arid ecosystems environmental factors such as geoclimatic conditions and agricultural practices are of major importance in shaping the diversity and functionality of plant-associated bacterial communities. Assessing the influence of such factors is a key to understand (i) the driving forces determining the shape of root-associated bacterial communities and (ii) the plant growth promoting (PGP) services they provide. Desert oasis environment was chosen as model ecosystem where agriculture is possible by the microclimate determined by the date palm cultivation. The bacterial communities in the soil fractions associated with the root system of date palms cultivated in seven oases in Tunisia were assessed by culture-independent and dependent approaches. According to 16S rRNA gene PCR-DGGE fingerprinting, the shapes of the date palm rhizosphere bacterial communities correlate with geoclimatic features along a north-south aridity transect. Despite the fact that the date palm root bacterial community structure was strongly influenced by macroecological factors, the potential rhizosphere services reflected in the PGP traits of isolates screenedin vitrowere conserved among the different oases. Such services were exerted by the 83% of the screened isolates. The comparable numbers and types of PGP traits indicate their importance in maintaining the plant functional homeostasis despite the different environmental selection pressures.
On the Molecular Modeling Analyses of Novel HIV-1 Protease Inhibitors Based on Modified Chitosan Dimer
Authors: Al-Fifi Zarrag , Saleh Noha A. , Elhaes Hanan , Ibrahim Medhat
Published: March 2015

The molecular modeling studies include quantitative structure activity relationship, IR spectra, and docking calculations, occurring for novel inhibitors based on chitosan dimer which were tried as HIV protease. The inhibitors were investigated with molecular modeling calculations at different level of theories. Each compound has phenol with hydroxymethylcarbonyl (HMC) group which added to chitosan in positions 2, 3, 2′, or 3′. The geometry of studied compounds is optimized with semiempirical PM3 method. Quantitative structure activity relationship (QSAR) properties of the suggested compounds are calculated at the same level of theory. Depending on QSAR calculations, the compounds with positions 2 and 2′ are less hydrophilic. The position 2′ compound makes good docking interaction into HIV protease active site. Calculated IR spectra indicate that the interaction through hydrogen bonding through the hydrogen of OH at positions 3 and 3′ gives rise to two OH bands one for chitosan and the other for phenol and HMC group. While at position 3′ CH band starts to appear.
Construction of a CXCL12-KDEL Fusion Gene to Inhibit Head and Neck Squamous Cell Carcinoma Metastasis by Intracellular Sequestration of CXCR4
Authors: Zhang Wenchao , Wang Xudong , Yue Kai , Liu Su , Liu Xiaonan
Published: March 2015

The CXCL12-CXCR4 biological axis consisting of the chemotactic factor CXCL12 and its specific receptor CXCR4 plays an important role in oral cancer metastasis. High expression of CXCR4 may help oral squamous cancer cells invade local tissues and metastasize to lymph nodes. No obvious association was observed between CXCL12 expression and lymph node metastasis, suggesting that CXCL12 chemotaxis may only be related to CXCR4 expression on the tumor cell membrane. KDEL can be retained by receptors on the surface of the intracellular endoplasmic reticulum (ER) and also be called an ER retention signal sequence. So we adopted the KDEL sequence in this study to generate a CXCL12-KDEL fusion protein in combination with a traceable E-tag label. As such, CXCL12 was retained in the ER. Specific receptor CXCR4 binds to the CXCL12-KDEL, was also retained in the ER, and was thus prevented from reaching the oral squamous cancer cell surface. We reduced the cell surface level of CXCR4 and called the technique “intracellular sequestration.” By this way, we have finished blocking of CXCL12-CXCR4 biological axis and inhibiting lymph node metastasis of oral carcinoma.
Occurrence of West Nile Virus Antibodies in Wild Birds, Horses, and Humans in Poland
Authors: Niczyporuk Jowita Samanta , Samorek-Salamonowicz Elżbieta , Lecollinet Sylvie , Pancewicz Sławomir Andrzej , Kozdruń Wojciech , Czekaj Hanna
Published: March 2015

Serum samples of 474 wild birds, 378 horses, and 42 humans with meningitis and lymphocytic meningitis were collected between 2010 and 2014 from different areas of Poland. West Nile virus (WNV) antibodies were detected using competition enzyme linked immunosorbent assays: ELISA-1 ID Screen West Nile Competition, IDvet, ELISA-2 ID Screen West Nile IgM Capture, and ELISA-3 Ingezim West Nile Compac. The antibodies were found in 63 (13.29%) out of 474 wild bird serum samples and in one (0.26%) out of 378 horse serum samples. Fourteen (33.33%) out of 42 sera from patients were positive against WNV antigen and one serum was doubtful. Positive samples obtained in birds were next retested with virus microneutralisation test to confirm positive results and cross-reactions with other antigens of the Japanese encephalitis complex. We suspect that positive serological results in humans, birds, and horses indicate that WNV can be somehow closely related with the ecosystem in Poland.
A Novel Time-Varying Friction Compensation Method for Servomechanism
Authors: Feng Bin , Zhang Dongsheng , Yang Jun , Guo Shijie
Published: March 2015

Friction is an inevitable nonlinear phenomenon existing in servomechanisms. Friction errors often affect their motion and contour accuracies during the reverse motion. To reduce friction errors, a novel time-varying friction compensation method is proposed to solve the problem that the traditional friction compensation methods hardly deal with. This problem leads to an unsatisfactory friction compensation performance and the motion and contour accuracies cannot be maintained effectively. In this method, a trapezoidal compensation pulse is adopted to compensate for the friction errors. A generalized regression neural network algorithm is used to generate the optimal pulse amplitude function. The optimal pulse duration function and the pulse amplitude function can be established by the pulse characteristic parameter learning and then the optimal friction compensation pulse can be generated. The feasibility of friction compensation method was verified on a high-precisionX-Yworktable. The experimental results indicated that the motion and contour accuracies were improved greatly with reduction of the friction errors, in different working conditions. Moreover, the overall friction compensation performance indicators were decreased by more than 54% and this friction compensation method can be implemented easily on most of servomechanisms in industry.
Identification of the Alternative Splicing of the UL49 Locus of Human Cytomegalovirus
Authors: Yang Guang , Li Wei , Liao Wenzhen , Zhang Xin , Zou Yi , Dai Jianfeng , Li Yueqin , Jing Chunxia , Zhou Tianhong
Published: March 2015

The UL49 ORF of human cytomegalovirus (HCMV) is essential for viral replication; conserved among all herpes viruses; however, the function is unclear. Once the UL49 ORF was precisely deleted from the start to stop codon, the mutant did not yield infectious progeny. In this study, we find out many alternatively processed ESTs in UL49 locus in HCMV-infected cells, in which there are two novel transcription termination sites in UL49 locus. Most of these ESTs are rare transcripts that contain directed repeat sequences in the intron splicing regions. There is a typical GU-AG intron splicing site in UL49Y transcripts. The 1847 bp UL49Y cDNA spans an ORF from 335 to 1618 and encodes a putative protein of 427 amino acids with a predicted molecular mass of 47.1 kDa. All the new EST sequences and UL49Y cDNA sequence have been deposited in the GenBank database (GenBank Accession nos. GW314860-GW314900 and GU376796). This study provides us with very important clues for revealing the importance of the UL49 locus alternative splicing.
New Application for the Generalized Incomplete Gamma Function in the Heat Transfer of Nanofluids via Two Transformations
Authors: Ebaid Abdelhalim , Alhawiti Hibah S.
Published: March 2015

The boundary layer flow of nanofluids is usually described by a system of nonlinear differential equations with infinity boundary conditions. These boundary conditions at infinity are transformed into classical boundary conditions via two different transformations. Accordingly, the original heat transfer equation is changed into a new one which is expressed in terms of the new variable. The exact solutions have been obtained in terms of the exponential function for the stream function and in terms of the incomplete Gamma function for the temperature distribution. Furthermore, it is found in this project that a certain transformation reduces the computational work required to obtain the exact solution of the heat transfer equation. Hence, such transformation is recommended for future analysis of similar physical problems. Besides, the other published exact solution was expressed in terms of the WhittakerM function which is more complicated than the generalized incomplete Gamma function of the current analysis. It is important to refer to the fact that the analytical procedure followed in our project is easier and more direct than the one considered in a previous published work.
Effects of Extrusion Pretreatment Parameters on Sweet Sorghum Bagasse Enzymatic Hydrolysis and Its Subsequent Conversion into Bioethanol
Authors: Heredia-Olea Erick , Pérez-Carrillo Esther , Montoya-Chiw Manuel , Serna-Saldívar Sergio O.
Published: March 2015

Second-generation bioethanol production from sweet sorghum bagasse first extruded at different conditions and then treated with cell wall degrading enzymes and fermented withI. orientaliswas determined. The twin extruder parameters tested were barrel temperature, screws speed, and feedstock moisture content using surface response methodology. The best extrusion conditions were 100°C, 200 rpm, and 30% conditioning moisture content. This nonchemical and continuous pretreatment did not generate inhibitory compounds. The extruded feedstocks were saccharified varying the biocatalysis time and solids loading. The best conditions were 20% solids loading and 72 h of enzymatic treatment. These particular conditions converted 70% of the total fibrous carbohydrates into total fermentable C5 and C6 sugars. The extruded enzymatically hydrolyzed sweet sorghum bagasse was fermented with the strainI. orientalisat 12% solids obtaining a yield of 198.1 mL of ethanol per kilogram of bagasse (dw).
The Global Ecology and Epidemiology of West Nile Virus
Authors: Chancey Caren , Grinev Andriyan , Volkova Evgeniya , Rios Maria
Published: March 2015

Since its initial isolation in Uganda in 1937 through the present, West Nile virus (WNV) has become an important cause of human and animal disease worldwide. WNV, an enveloped virus of the genusFlavivirus, is naturally maintained in an enzootic cycle between birds and mosquitoes, with occasional epizootic spillover causing disease in humans and horses. The mosquito vectors for WNV are widely distributed worldwide, and the known geographic range of WNV transmission and disease has continued to increase over the past 77 years. While most human infections with WNV are asymptomatic, severe neurological disease may develop resulting in long-term sequelae or death. Surveillance and preventive measures are an ongoing need to reduce the public health impact of WNV in areas with the potential for transmission.
Identification of Subtype Specific miRNA-mRNA Functional Regulatory Modules in Matched miRNA-mRNA Expression Data: Multiple Myeloma as a Case
Authors: Zhang Yunpeng , Liu Wei , Xu Yanjun , Li Chunquan , Wang Yingying , Yang Haixiu , Zhang Chunlong , Su Fei , Li Yixue , Li Xia
Published: March 2015

Identification of miRNA-mRNA modules is an important step to elucidate their combinatorial effect on the pathogenesis and mechanisms underlying complex diseases. Current identification methods primarily are based upon miRNA-target information and matched miRNA and mRNA expression profiles. However, for heterogeneous diseases, the miRNA-mRNA regulatory mechanisms may differ between subtypes, leading to differences in clinical behavior. In order to explore the pathogenesis of each subtype, it is important to identify subtype specific miRNA-mRNA modules. In this study, we integrated the Ping-Pong algorithm and multiobjective genetic algorithm to identify subtype specific miRNA-mRNA functional regulatory modules (MFRMs) through integrative analysis of three biological data sets: GO biological processes, miRNA target information, and matched miRNA and mRNA expression data. We applied our method on a heterogeneous disease, multiple myeloma (MM), to identify MM subtype specific MFRMs. The constructed miRNA-mRNA regulatory networks provide modular outlook at subtype specific miRNA-mRNA interactions. Furthermore, clustering analysis demonstrated that heterogeneous MFRMs were able to separate corresponding MM subtypes. These subtype specific MFRMs may aid in the further elucidation of the pathogenesis of each subtype and may serve to guide MM subtype diagnosis and treatment.
Genetic and Technological Characterisation of Vineyard- and Winery-Associated Lactic Acid Bacteria
Authors: Nisiotou Aspasia A. , Dourou Dimitra , Filippousi Maria-Evangelia , Diamantea Ellie , Fragkoulis Petros , Tassou Chryssoula , Banilas Georgios
Published: March 2015

Vineyard- and winery-associated lactic acid bacteria (LAB) from two major PDO regions in Greece, Peza and Nemea, were surveyed. LAB were isolated from grapes, fermenting musts, and winery tanks performing spontaneous malolactic fermentations (MLF). Higher population density and species richness were detected in Nemea than in Peza vineyards and on grapes than in fermenting musts.Pediococcus pentosaceusandLactobacillus graminiswere the most abundant LAB on grapes, whileLactobacillus plantarumdominated in fermenting musts from both regions. No particular structure ofLactobacillus plantarumpopulations according to the region of origin was observed, and strain distribution seems random. LAB species diversity in winery tanks differed significantly from that in vineyard samples, consisting principally ofOenococcus oeni. Different strains were analysed as per their enological characteristics and the ability to produce biogenic amines (BAs). Winery-associated species showed higher resistance to low pH, ethanol, SO2, and CuSO4than vineyard-associated isolates. The frequency of BA-producing strains was relatively low but not negligible, considering that certain winery-associatedLactobacillus hilgardiistrains were able to produce BAs. Present results show the necessity of controlling the MLF by selected starters in order to avoid BA accumulation in wine.