bluuebunny/crossref_metadata_2025_split huggingface dataset:
Drought impact on water use efficiency and intra‐annual density fluctuations in Erica arborea on Elba (Italy)
Authors: BATTIPAGLIA GIOVANNA , DE MICCO VERONICA , BRAND WILLI A. , SAURER MATTHIAS , ARONNE GIOVANNA , LINKE PETRA , CHERUBINI PAOLO 
Published: July 2013

AbstractErica arborea (L) is a widespread Mediterranean species, able to cope with water stress and colonize semiarid environments. The eco‐physiological plasticity of this species was evaluated by studying plants growing at two sites with different soil moistures on the island of Elba (Italy), through dendrochronological, wood‐anatomical analyses and stable isotopes measurements. Intra‐annual density fluctuations (IADFs) were abundant in tree rings, and were identified as the key parameter to understand site‐specific plant responses to water stress. Our findings showed that the formation of IADFs is mainly related to the high temperature, precipitation patterns and probably to soil water availability, which differs at the selected study sites. The recorded increase in the 13C‐derived intrinsic water use efficiency at the IADFs level was linked to reduced water loss rather than to increasing C assimilation. The variation in vessel size and the different absolute values of δ18O among trees growing at the two study sites underlined possible differences in stomatal control of water loss and possible differences in sources of water uptake. This approach not only helped monitor seasonal environmental differences through tree‐ring width, but also added valuable information on E. arborea responses to drought and their ecological implications for Mediterranean vegetation dynamics.
Singlet oxygen scavenging activity of tocopherol and plastochromanol in Arabidopsis thaliana: relevance to photooxidative stress
Authors: RASTOGI ANSHU , YADAV DEEPAK KUMAR , SZYMAŃSKA RENATA , KRUK JERZY , SEDLÁŘOVÁ MICHAELA , POSPÍŠIL PAVEL 
Published: July 2013

AbstractIn the present study, singlet oxygen (1O2) scavenging activity of tocopherol and plastochromanol was examined in tocopherol cyclase‐deficient mutant (vte1) of Arabidopsis thaliana lacking both tocopherol and plastochromanol. It is demonstrated here that suppression of tocopherol and plastochromanol synthesis in chloroplasts isolated from vte1 Arabidopsis plants enhanced 1O2 formation under high light illumination as monitored by electron paramagnetic resonance spin‐trapping spectroscopy. The exposure of vte1 Arabidopsis plants to high light resulted in the formation of secondary lipid peroxidation product malondialdehyde as determined by high‐pressure liquid chromatography. Furthermore, it is shown here that the imaging of ultra‐weak photon emission known to reflect oxidation of lipids was unambiguously higher in vte1 Arabidopsis plants. Our results indicate that tocopherol and plastochromanol act as efficient 1O2 scavengers and protect effectively lipids against photooxidative damage in Arabidopsis plants.
The ‘Modified Union Jack’ Repair of a Lesser Tuberosity Osteotomy in Total Shoulder Arthroplasty: Surgical Technique and Radiological Results
Authors: Smith Geoffrey C. S. , Da Costa Thomas Mendes , Sarangi Partha 
Published: July 2013

Background Several different techniques have been described for repairing a lesser tuberosity osteotomy in shoulder arthroplasty, although all have potential drawbacks. We describe a novel repair technique and its radiological results. Methods All patients undergoing a total shoulder arthroplasty using a resurfacing humeral component from 2008 to date were identified retrospectively. Anteroposterior (AP) and axial radiographs at a minimum of 3 months postoperatively were used to assess union of the osteotomy fragment. Results Seventy-six total shoulder replacements in 65 patients were eligible for review. Seven were excluded as a result of inadequate radiographs. Sixty-six of 69 had united (95.6%). There were two cases (2.9%) of a complete non-union that was undisplaced. In one patient (1.4%), the osteotomy fragment had displaced and this was apparent on the initial postoperative AP radiograph. Conclusions The modified union jack repair technique is simple, fast, economical and reliable.
Trade Creation and Diversion Effects of Regional Trade Agreements: A Product‐level Analysis
Authors: Urata Shujiro , Okabe Misa 
Published: July 2013

AbstractThis paper examines the impacts of regional trade agreements (RTAs) on trade flows at product level, with a particular focus on trade creation and diversion. Based on estimation of the gravity equation, dealing with the zero trade flows and endogeneity bias problems, we analyse the impacts of various types of RTAs involving 67 countries for 20 products during the 1980–2006 period. We find that RTAs among developing countries tend to cause trade diversion compared with RTAs among developed countries. Taking the higher external tariff rates of developing countries compared with developed countries into consideration, our results suggest trade diversion is likely to be caused by remaining high tariffs on imports from non‐members. In addition, we find the trade creation effect for many products in the cases of Customs Unions and plurilateral RTAs. These results imply that trade creation would be caused by various factors besides the reduction in tariff rates. Based on these results, we draw a policy implication that external tariff rate reduction is an important factor in avoiding trade diversion in the formation of RTAs, in particular for RTAs among developing countries, while a large number of members and the common external tariff appear to be important for generating the trade creation effect.
Intravenous administration of desmopressin acetate to reverse acetylsalicylic acid‐induced coagulopathy in three dogs
Authors: Di Mauro Francesca M. , Holowaychuk Marie K. 
Published: July 2013

AbstractBackgroundAcetylsalicylic acid (ie, aspirin) administration inhibits platelet aggregation in dogs and is associated with increased perioperative blood loss and transfusion requirements in people. Desmopressin acetate (DDAVP) is used to control or prevent bleeding in dogs with type 1 von Willebrand disease and is also widely reported in the human literature as an emergency antithrombotic reversal agent.Key FindingsThree dogs undergoing surgery for intervertebral disc disease had marked prolongations in buccal mucosal bleeding time (BMBT) after aspirin administration. DDAVP was given intravenously preoperatively and achieved prompt reversal of the prolongation in BMBT. None of the dogs experienced intraoperative bleeding complications.SignificanceIV DDAVP corrected prolongations in BMBT in dogs given aspirin and should be considered in dogs requiring prompt reversal of aspirin‐induced coagulopathies to reduce the risk of bleeding complications.
Pneumomediastinum in cats: 45 cases (2000–2010)
Authors: Thomas Emily K. , Syring Rebecca S. 
Published: July 2013

AbstractObjectiveTo characterize the incidence, etiology, presenting complaint, clinical course, and outcome of cats with pneumomediastinum.DesignRetrospective study from the period of January 1st, 2000 to December 31st, 2010.SettingUniversity teaching hospital.AnimalsForty‐five cats with a radiographic diagnosis of pneumomediastinum.InterventionsNone.Measurements and Main ResultsMedical and radiographic records were reviewed to identify cats with a radiographic diagnosis of pneumomediastinum. Clinical data were retrieved, including signalment, history, presenting clinical signs, diagnostic test results, treatment, complications, and survival to discharge. In 31 of 45 (69%) cats the pneumomediastinum was secondary to an obvious inciting cause. General anesthesia with endotracheal intubation and positive pressure ventilation was the most common cause in 17 of 45 (38%) cases. This was followed by trauma in 12 of 45 (27%) cats, and tracheal foreign bodies in 2 of 45 (4%) cats. Spontaneous pneumomediastinum (unknown underlying cause) was diagnosed in 14 of 45 (31%) of cases. Onset of clinical signs and diagnosis of spontaneous pneumomediastinum was preceded by emesis in 6 of 14 cats. Common presenting signs were tachypnea seen in 27 of 45 (60%) cats, increased respiratory effort in 26 of 45 (58%) cats, and subcutaneous emphysema in 30 of 45 (66%) cats. Concurrent pneumothorax was identified in 21 of 45 (47%) cats, pleural effusion in 10 of 45 (22%), and pneumoretroperitoneum in 21 of 45 (47%). The mainstay of treatment was supportive care and treatment of the underlying disease process. The prognosis for recovery was good, with 87% survival until hospital discharge.ConclusionsPneumomediastinum in cats is an infrequently diagnosed condition. It is often secondary to an event such as general anesthesia with endotracheal intubation and positive pressure ventilation but less frequently may occur spontaneously. The prognosis is good with appropriate supportive care.
Management of acute respiratory distress syndrome in a French Bulldog using airway pressure release ventilation
Authors: Sabino Catherine V. , Holowaychuk Marie , Bateman Shane 
Published: July 2013

AbstractObjectiveTo describe the successful clinical management of a dog with acute respiratory distress syndrome (ARDS) using airway pressure release ventilation (APRV).Case SummaryAn 18‐month‐old female French Bulldog was presented for routine ovariohysterectomy and correction of brachycephalic airway obstruction syndrome. Following the surgical procedures, the dog developed aspiration pneumonia and ARDS. Her clinical condition failed to improve with conventional pressure‐support mechanical ventilation and she was subsequently managed with APRV. She recovered fully and exhibited no clinical or radiographic abnormalities during follow‐up examinations.New or Unique Information ProvidedThis is the first reported use of APRV to manage refractory hypoxemia associated with ARDS in a dog. This alternative mode of mechanical ventilation can be considered a feasible alternative in canine patients with ARDS.
Evaluation of the shock index in dogs presenting as emergencies
Authors: Porter Adam E. , Rozanski Elizabeth A. , Sharp Claire R. , Dixon Kursten L. , Price Lori Lyn , Shaw Scott P. 
Published: July 2013

AbstractObjectivesTo (1) determine a reference interval for shock index (SI) [defined as heart rate (HR)/systolic blood pressure (SBP)], in a group of healthy dogs, and (2) compare SI in healthy dogs with dogs presenting to the emergency room (ER) deemed to be in or not in a state of shock.DesignProspective study.AnimalsSixty‐eight clinically normal dogs, 18 dogs that were presented to the ER deemed to be in shock and 19 dogs presenting to the ER not deemed to be in shock.SettingUniversity teaching hospital.InterventionsPeripheral or central venous blood sampling.Measurements and Main ResultsHeart rate and SBP were recorded on simulated presentation (healthy dogs), and emergency presentations for both dogs deemed to be in shock and dogs not deemed in shock. Dogs in shock had a median SI of 1.37 (0.87–3.13), which was significantly higher than both other groups; dogs not deemed in shock had median SI 0.73 (0.56–1.20),P< 0.0001 and healthy dogs had median SI 0.78 (0.37–1.30)P< 0.0001), respectively. Receiver operator characteristic curve analysis suggested a SI cut‐off of 1.0, yielding an area under the receiver operator characteristic (AUROC) of 0.89 (Specificity (Sp) 89, Sensitivity (Sn) 90) when comparing dogs deemed in shock with healthy dogs, and 0.92 (Sp 95, Sn 89) when comparing dogs in shock with to dogs not deemed in shock.ConclusionsThe SI is an easy and noninvasive patient parameter that is higher in dogs that are deemed to be in shock than both healthy dogs and dogs presented as emergencies but not deemed to be in a state of shock. The measurement of SI may have some benefit in clinical assessment of emergency patients.
Fuelling Micro Gas Turbines With Vegetable Oils: Part I — Straight and Blended Vegetable Oil Properties
Authors: Cavarzere A. , Morini M. , Pinelli M. , Spina P. R. , Vaccari A. , Venturini M. 
Published: July 2013

Current energy policies tend to encourage the production of renewable energy for environmental reasons and energy independence. Among renewable sources, biomass can play a key role, because of economic, environmental and political factors, such as the need to diversify and improve energy supply, reduce the greenhouse effect and support rural areas.
For the case of liquid biofuels derived from agricultural crops, several possibilities can be considered, such as straight vegetable oil (SVO), oil-derived esters, bioethanol or blends with conventional fuels (diesel or gasoline). The use of SVOs and their derivatives usually poses some problems, that essentially derive from their much higher viscosity and higher boiling temperature.
In order to evaluate the technical feasibility of the use of SVOs within gas turbine combustors, this paper reports the results of the experimental characterization of different vegetable oils, derived from dedicated crops. Moreover, blends composed of diesel and vegetable oil in different concentrations (from pure diesel to pure vegetable oil) are also considered and their experimental characterization is also reported, with particular focus on blend viscosity. The considered vegetable oils were obtained from different types of oilseeds (rapeseed, sunflower, soybean) and were cultivated under different agronomic scenarios. The SVO properties determined experimentally are SVO elemental composition, lower heating value, density, specific heat and viscosity, for which this paper provides a practical overview, coming both from experiments and literature data.
Optical Structures for High Speed Gas Temperature Measurement
Authors: Harpin A. P. R. , Langton C. 
Published: July 2013

This paper reports on recent work to produce a sensor based on optical waveguides. The geometry of the structure will be described and its response to changes in gas temperature will be modelled. The validity of the modelling will be examined by comparing with actual results — taken with preliminary flowing gas/heat gun experiments, and by using the technique of heating the sensor with a laser and measuring the decay time, and examining its causes. The response of a bulk sapphire sensor of the sort currently suited to installation in a gas turbine will be similarly examined. This will show the advantage of the waveguide sensor in terms of speed and the pros and cons of each type will be evaluated for a gas turbine, using published data for gas flows and convection coefficients in a gas turbine representative location.
The requirements for high speed of operation (i.e. rapid response to changes in surrounding gas temperature) and low conduction to the sensor package/mounting will be examined and the arrival at a waveguide based structure will be justified. A diaphragm structure is proposed, modelled and fabricated. It is found that there are tradeoffs in the design for speed of response against conduction crosstalk, and limitations on the gas flows that will yield accurate results. These will be examined theoretically and experimentally.
Due to the use of fibre optic interconnects between the sensor and the remote interrogator, EMI (electromagnetic interference) issues are well controlled. The packaging scheme used to package such a sensor including its optical connection will be described, and its performance in harsh environments such as an engine exhaust will be demonstrated.
Finally, the performance of such a sensor in a reciprocating engine manifold will be presented, together with an interpretation of the results and conclusions therefrom.
Transient Temperature Measurements in the Contact Zone Between Brush Seals of Kevlar and Metallic Type for Bearing Chamber Sealing Using a Pyrometric Technique
Authors: Flouros Michael , Stadlbauer Martin , Cottier Francois , Proestler Stephan , Beichl Stefan 
Published: July 2013

For the past 25 years brush seal technologies evolved into the aero engine designs and more general into the gas turbine world not only for sealing gas areas at different pressure levels but also for sealing gas/liquid environments. This is the case in an aero engine where the bearing chambers are sealed. Aero engine bearing chambers enclose oil lubricated components such bearings and gears. In order to avoid contamination of the turbo machinery through oil loss, air blown seals are used to retain the oil into the bearing chamber. Oil loss may cause coking or ignition with the probability of an uncontained destruction of rotating parts like disks or blades. It may also cause contamination of the air conditioning system with oil fumes thus cause health problems to the passengers and crew from such exposure.
The most widely known seals for bearing chamber sealing are the labyrinth seals but in the recent years also brush seals and carbon seals are used. The latter are contact seals, that is, they may be installed having zero clearance to the rotating part and lift during operation when their air side is pressurized.
During this survey an actual aero engine bearing chamber was modified to run with brush seals in a simulating rig. Two types of brush seals were used: a) with bristles made of Kevlar and b) bristles made of metallic material. Both types were installed with an overlap to the rotor.
The targets set were twofold: a) to measure the transient temperatures in the rotor and particularly in the contact zone between the bristles and the rotor and b) to measure the air leakage through the seals at different operating conditions.
In order to obtain the transient temperature measurements with high fidelity, a new pyrometric technique was developed and was applied for the first time in brush seals. This technique has enabled placing the pyrometer into the bristle’s pack of the seal adjacent to the rotating surface and could record the frictional temperature evolution in the bristles/rotor contact zone during acceleration or deceleration of the rotor. Additionally, the air consumption of the seals was measured and was compared to the air consumption through the labyrinth seals. For the metallic brush seal, up to 80% of the required sealing air can be saved which can result in return into a reduction in fuel burned by up to 1%. Further, a design simplification of the bearing chamber architecture can be achieved by taking into account the reduced air flow. Even though the rotor was accelerated to high speeds up to 19500rpm, the produced temperature overshoots in the seal/rotor contact zone have caused no deterioration in either the materials or the oil.
This work is part of the European Union funded research programme ELUBSYS (Engine LUBrication System TechnologieS) within the 7th EU Frame Programme for Aeronautics and Transport (AAT.2008.4.2.3).
Fuel System Design for the More Electric Engine
Authors: Morioka Noriko , Oyori Hitoshi 
Published: July 2013

This paper describes the system design of an electric motor-driven fuel pump system for the MEE (More Electric Engine). The MEE is a new aircraft engine system concept which will reduce fuel burn and CO2 emissions, and improve engine safety, reliability and maintainability. At the initial concept design stage of the MEE, a feasibility study indicated that the electric fuel pump system helped improve engine efficiency. The selected fuel pump system configuration for the MEE was a fixed displacement gear pump system, the speed of which is controlled by an electric motor. Simplification of the fuel system will be expected because the electric gear pump itself is used as a metering device, but there are several technical challenges which should be overcome to realize the system.
One of the technical challenges involves ensuring fuel metering accuracy via motor speed control. To address the issue, studies of the fuel flow rate feedback system were performed. A novel flow feedback system was investigated and the potential to ensure metering accuracy was confirmed.
The other technical challenge is the wide speed range operation of the gear pump system. If only a single electric gear pump is used in the MEE system, the pump should accommodate a speed range of 5 to 100% because the ground starting flow rate is about 5% of the maximum flow. Operation at such low speeds is significantly harsh for the LP pump pressurizing capability and bearing film lubrication. However, optimized pump performance and operational condition were established, and it is expected that a single pump system, in which both LP and HP pumps are directly motor-driven via a single shaft, can be constructed. In addition, there is a technical challenge involved in supplying electrical power to the pump motor during the windmill engine start-up.
The system design focused on the above technical challenges, and the consequent feasibility of the simplified MEE fuel pump system construction was confirmed.
Comparing Lensed and Un-Lensed Optical Spot Probes for Blade Tip Timing Measurements
Authors: Hockaday Bruce D. 
Published: July 2013

Detection of airfoil time-of-arrival with optical probes has been evolving since the 1980s. Time of arrival data are used to infer airfoil stresses caused by vibration through a sequence of manipulations. The data conversion begins by converting arrival time to blade position, so blade deflection can be determined from the expected non-vibrating position. Various methods are used in the industry to convert deflection data to frequency, amplitude, and stress, which is beyond the scope of this paper. Regardless of the analytical approach used, producing accurate stress information relies on the precise detection and measurement of time-of-arrival, which equates to blade position.
Optical spot probes are commonly employed for blade tip sensing. Two dominant types of fiber optic probes are used in industry today; 1) un-lensed probes having their numerical aperture (NA) defined by the optical fiber and 2) lensed probes, utilizing an imaging lens to control numerical aperture and spot size. The lens adds cost and complexity to the probe but allows the probe to be installed farther away from the blade tip while keeping the sensing area small. The low-cost un-lensed probes must be installed close to the blade tip since the optical beam diverges at the angle defined by the NA of the fiber. These probes are considered interchangeable, with little regard to the inherent geometric optical differences of the beam transmission into the space where the blade travels.
This paper presents a laboratory study comparing the performance characteristics between lensed and un-lensed spot probes. The study evaluates signal amplitude and rise time and arrival errors due to optical interaction with varying tip radii geometry. The study reports rise time as return signal strength as a function of circumferential location and sensing gap. Arrival errors are reported as circumferential location errors compared to a sharp reference edge as a function of the blade-to-sensor gap. The work is presented in terms of arrival location, producing information that is independent of rotation speed and vibratory mode.