bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of leg length on jumping performance of short- and long-legged leafhopper insects
Authors: Burrows M. , Sutton G. P. 
Published: March 2008

SUMMARYTo assess the effect of leg length on jumping ability in small insects, the jumping movements and performance of a sub-family of leafhopper insects(Hemiptera, Auchenorrhyncha, Cicadellidae, Ulopinae) with short hind legs were analysed and compared with other long-legged cicadellids (Hemiptera,Auchenorrhyncha, Cicadellidae). Two species with the same jumping characteristics but distinctively different body shapes were analysed: Ulopa, which had an average body length of 3 mm and was squat, and Cephalelus, which had an average body length of 13 mm with an elongated body and head. In both, the hind legs were only 1.4 times longer than the front legs compared with 1.9–2.3 times in other cicadellid leafhoppers. When the length of the hind legs was normalised relative to the cube root of their body mass, their hind legs had a value of 1–1.1 compared with 1.6–2.3 in other cicadellids. The hind legs of Cephalelus were only 20% of the body length. The propulsion for a jump was delivered by rapid and synchronous rotation of the hind legs about their coxo-trochanteral joints in a three-phase movement, as revealed by high-speed sequences of images captured at rates of 5000 s–1. The hind tarsi were initially placed outside the lateral margins of the body and not apposed to each other beneath the body as in long-legged leafhoppers. The hind legs were accelerated in 1.5 ms (Ulopa) and 2 ms(Cephalelus) and thus more quickly than in the long-legged cicadellids. In their best jumps these movements propelled Ulopa to a take-off velocity of 2.3 m s–1 and Cephalelus to 2 m s–1, which matches that of the long-legged cicadellids. Both short-legged species had the same mean take-off angle of 56° but Cephalelus adopted a lower angle of the body relative to the ground(mean 15°) than Ulopa (mean 56°). Once airborne, Cephalelus pitched slowly and rolled quickly about its long axis and Ulopa rotated quickly about both axes. To achieve their best performances Ulopa expended 7 μJ of energy, generated a power output of 7 mW, and exerted a force of 6 mN; Cephalelus expended 23μJ of energy, generated a power output of 12 mW and exerted a force of 11 mN. There was no correlation between leg length and take-off velocity in the long- and short-legged species, but longer legged leafhoppers had longer take-off times and generated lower ground reaction forces than short-legged leafhoppers, possibly allowing the longer legged leafhoppers to jump from less stiff substrates.
Honeybees can recognise images of complex natural scenes for use as potential landmarks
Authors: Dyer Adrian G. , Rosa Marcello G. P. , Reser David H. 
Published: March 2008

SUMMARYThe ability to navigate long distances to find rewarding flowers and return home is a key factor in the survival of honeybees (Apis mellifera). To reliably perform this task, bees combine both odometric and landmark cues,which potentially creates a dilemma since environments rich in odometric cues might be poor in salient landmark cues, and vice versa. In the present study, honeybees were provided with differential conditioning to images of complex natural scenes, in order to determine if they could reliably learn to discriminate between very similar scenes, and to recognise a learnt scene from a novel distractor scene. Choices made by individual bees were modelled with signal detection theory, and bees demonstrated an ability to discriminate between perceptually similar target and distractor views despite similar spatiotemporal content of the images. In a non-rewarded transfer test bees were also able to recognise target stimuli from novel distractors. These findings indicate that visual processing in bees is sufficiently accurate for recognising views of complex scenery as potential landmarks, which would enable bees flying in a forest to use trees both as landmark and/or odometric cues.
The tip of the superbug iceberg
Authors: Rawson Edwina 
Published: March 2008

Thousands of patients die or are made seriously ill by healthcare infections, popularly known as ‘superbugs’. This is a fact. It is also a fact that a proportion of these could have been avoided if hospitals and staff were, simply, cleaner. The press is littered with heartbreaking stories of superbugs: 33 die and 334 are infected due to an outbreak of Clostridium difficile at Stoke Mandeville Hospital; 90 die following a similar outbreak at Maidstone Hospital; a two-day old baby dies from MRSA at Ipswich Hospital; a mother dies of MRSA shortly after giving birth at Stoke-on-Trent Hospital; a young nurse dies, a male patient nearly dies and 17 others are infected after a pseudomonas outbreak at Guy's Hospital. There are many others. It is a major national problem. Despite this, we are told only of the tip of the iceberg. In addition, one would hope that the law provided appropriate redress to superbug victims, but this is often not the case.
Pregnancy-induced lymphangiectasias of the vulva
Authors: Verma Shyam 
Published: March 2008

Summary Lymphangiectasias occuring as a consequence of pregnancy and spontaneously regressing upon successful outcome of pregnancy is a rarity that needs to be reported. More so because these lesions occuring on the vulva can mimic various other entities and can sometimes be misconstrued as sexually transmitted disease by persons involved in primary care. This is a case report of lymphangiectasias occuring during pregnancy.
Be wary, this is not a case of vulval warts!
Authors: Basta Medhat S T , Sharma Kirti , Chauhan Mayur 
Published: March 2008

Summary We present a 40-year-old woman who presented to the genitourinary medicine department with a two-year history of recurrent non-painful vulval lumps. She was in a stable relation with one male sexual partner over the preceding 20 years and her sexual health screen was negative. Clinical examination of these lumps was suggestive of anogenital warts for which she has been treated on numerous occasions over the last two-year-period with liquid nitrogen cryotherapy and podophyllotoxin 0.15% cream. As the lumps were not responding to conventional wart treatment, a biopsy from these lesions was performed. The histological appearance showed focal fibrin thrombus formation within dilated vascular channels consistent of a subepidermal cavernous haemangioma. This case demonstrates that the clinical diagnosis of anogenital warts is not always straightforward. It highlights the importance of obtaining a tissue diagnosis from the resistant or atypically looking warty lesions to avoid making the wrong diagnosis.
Endovenous laser ablation: an experimental study on the mechanism of action
Authors: Disselhoff B C V M , Rem A I , Verdaasdonk R M , Kinderen D J der , Moll F L 
Published: March 2008

Objectives The aim of this experimental study was to investigate the mechanism of action of endovenous laser ablation (EVLA) using an 810-nm diode laser. Methods We compared intermittent and continuous delivery of laser energy and studied the absorption of laser light by blood, intravascular temperatures in ex vivo human vein segments using an intravascular thermography catheter and heat dissipation in a model tissue using the Schlieren technique. Results Laser light is absorbed by blood and converted to heat leading to coagulation, vaporization and carbonization, and forming an isolating layer at the fibre tip. Laser energy is then absorbed into the isolating layer forming black patches that burned on the laser fibre. Intravascular temperature increased rapidly above carbonization temperatures (300°C) after the fibre tip reached the thermocouple, stayed at this temperature for a few seconds and decreased gradually to around 30°C, 10 s after the fibre tip passed the thermocouple. Schlieren techniques revealed that heat spread from the laser was locally distributed and closely around the laser fibre tip while heat dissipation is minimal and comparable for both exposures. Compared with intermittent exposure, continuous exposure results in more carbonization, higher mean maximum intravascular temperature (128 ± 7 vs. 75 ± 4°C), and long-lasting temperature of 100°C (1.2 ± 0.4 vs. 0.1 ± 0.1 s). Conclusion In this experimental study, application of endovenous laser shows to be dominated by carbonization at the fibre tip. Although intraluminal laser-induced heat was heterogeneously distributed, with laser tip temperatures up to 1200°C, heat dissipation was minimal. Continuous exposure of laser light appears to be better suited in EVLA than intermittent.
Microfluidic Leukocyte Isolation for Gene Expression Analysis in Critically Ill Hospitalized Patients
Authors: Russom Aman , Sethu Palaniappan , Irimia Daniel , Mindrinos Michael N , Calvano Steve E , Garcia Iris , Finnerty Celeste , Tannahill Cynthia , Abouhamze Amer , Wilhelmy Julie , López M Cecilia , Baker Henry V , Herndon David N , Lowry Stephen F , Maier Ronald V , Davis Ronald W , Moldawer Lyle L , Tompkins Ronald G , Toner Mehmet ,   the Inflammation and Host Response to Injury Large Scale Collaborative Research Program
Published: March 2008

AbstractBackground: Microarray technology is becoming a powerful tool for diagnostic, therapeutic, and prognostic applications. There is at present no consensus regarding the optimal technique to isolate nucleic acids from blood leukocyte populations for subsequent expression analyses. Current collection and processing techniques pose significant challenges in the clinical setting. Here, we report the clinical validation of a novel microfluidic leukocyte nucleic acid isolation technique for gene expression analysis from critically ill, hospitalized patients that can be readily used on small volumes of blood.Methods: We processed whole blood from hospitalized patients after burn injury and severe blunt trauma according to the microfluidic and standard macroscale leukocyte isolation protocol. Side-by-side comparison of RNA quantity, quality, and genome-wide expression patterns was used to clinically validate the microfluidic technique.Results: When the microfluidic protocol was used for processing, sufficient amounts of total RNA were obtained for genome-wide expression analysis from 0.5 mL whole blood. We found that the leukocyte expression patterns from samples processed using the 2 protocols were concordant, and there was less variability introduced as a result of harvesting method than there existed between individuals.Conclusions: The novel microfluidic approach achieves leukocyte isolation in &lt;25 min, and the quality of nucleic acids and genome expression analysis is equivalent to or surpasses that obtained from macroscale approaches. Microfluidics can significantly improve the isolation of blood leukocytes for genomic analyses in the clinical setting.
Sill Pan Flashing for Block-Frame Windows in Recessed Concrete Openings—Case Studies
Authors: Bateman Robert 
Published: March 2008

Abstract
Integrating sill pan window flashing can be challenging using block-frame windows or installing flashings within a recessed opening in a concrete wall. Two case studies summarize the details of design and retrofit installation for sill pan flashing of replacement block-frame window into the perimeters of existing recessed concrete wall openings. Provisions for sill pan drainage were included with technical solutions for two case studies. The design and detailing were also conceived to account for blending with the context of the existing architecture and minimizing the aesthetic concerns for the appearance of any exposed perimeter opening flashings. These case studies demonstrate detailing methodologies for wood and metal block-frame window frames and concrete wall openings applicable for new and existing exterior wall systems.
Characterization of Zirconium Hydrides and Phase Field Approach to a Mesoscopic-Scale Modeling of Their Precipitation
Authors: Zhao Z. , Blat-Yrieix M. , Morniroli J.-P. , Legris A. , Thuinet L. , Kihn Y. , Ambard A. , Legras L. 
Published: March 2008

Abstract
Zirconium alloys are currently used in nuclear power plants where they are submitted to hydrogen pick-up. Hydrogen in solid solution or hydride precipitation can affect the behavior of zirconium alloys during service but also in long term storage and in accidental conditions. Numerical modeling at mesoscopic scale using a “phase field” approach has been launched to describe hydride precipitation and its consequences on the mechanical properties of zirconium alloys. To obtain realistic results, it should take into account an accurate kinetic, thermodynamic, and structural database in order to properly describe hydride nucleation, growth, and coalescence as well as hydride interaction with external stresses. Therefore, an accurate structural characterization was performed on Zircaloy-4 plates and it allowed us to identify a new zirconium hydride phase called ζ. The ζ phase has a trigonal symmetry and is fully coherent with hcp αZr. The consequences of this new zirconium hydride phase on hydride transformation process and stress-reorientation phenomenon are discussed. A first attempt to numerically model the precipitation of this new zirconium hydride phase has been undertaken using the phase field approach.
Innovative Gas Shutoff Method Using Heavy Oil-in-Water Emulsion
Authors: Zeidani K. , Polikar M. 
Published: March 2008

Abstract
Laboratory investigations were conducted to examine the effectiveness of heavy oil-in-water emulsion in plugging the near wellbore matrix, thereby reducing gas (and water) coning or eliminating gas leakage to the surface. Experiments at micro- and macro-scale levels were performed to: a) provide a detailed understanding of emulsion flow and blocking mechanism, b) set criteria for controlling an emulsion penetration depth before it breaks down and seals a porous medium.
In these experiments, well-characterized oil-in-water emulsions were injected into etched-glass micro-models and micro-models packed with glass beads. The effect of droplet-to-pore size ratio, droplet stability, oil and surfactant type and concentration were studied through visualization experiments. It was observed that blockage happened because of size exclusion. Also, the blockage was accelerated due to droplets coalescence as a result of high shear rate or surfactant adsorption on the porous medium. Furthermore, emulsion droplet size distribution, emulsion viscosity and oil droplets-to-water interfacial tensions increased as the surfactant content decreased, resulting in higher capillary pressure across the trapped oil droplet.
The effect of oil type, rock permeability, injection velocity, and wettability alteration were also studied. The results showed that emulsions carrying more viscous oils could resist higher pressures due to the combined effects of capillarity and viscosity. Also, conditioning the medium with pre-flush solutions predictably affected the depth to which an emulsion may penetrate into a porous medium. Surfactant and alkaline-based pre-flush solutions may enhance an emulsion penetration depth significantly. However, the emulsion may break down and emplace at a desired depth within a porous medium as a result of applying low pH solutions. Unconsolidated cores withstood 42,500 kPa/m (1,880 psi/ft) for a long period of time. Emulsions were optimized to seal cores with different permeabilities for the purpose of field application.
A novel cost-effective sealant that uses heavy oil-in-water emulsion to block the near wellbore region has been developed. Emulsion flow behavior and methods controlling its propagation rate into a porous medium will be presented.
The PUT River, Appraisal and Development of a Minor Reservoir within the Prudhoe Bay Field, North Slope, Alaska
Authors: Panda Manmath , Dean James , Pietras Jeff , Wheeler Tammy , Sels Roger 
Published: March 2008

Abstract
PUT River formation is an early Cretaceous reservoir in the North Slope, Alaska. Stratigraphically it lies above the Lower Cretaceous Unconformity (LCU) and below the Highly Radioactive Zone (HRZ). The reservoir sands are near shore face to shallow marine deposits with heavy bio-turbation.
In the Prudhoe Bay Field the PUT River reservoir overlays the Sadlerochit interval, the main producing horizon. A number of the Prudhoe Bay development wells penetrate the PUT River reservoir and provide well control for defining the areal extent and thickness of the reservoir.
Four lobes of the PUT River were appraised by recompleting existing Sadlerochit wells that penetrated PUT River. The oil filled south-east lobe is the target of the current development plan. A key uncertainty of the development plan was the transmissibility across the faults.
Three dimensional (3D) stochastic reservoir models were constructed and matched with the appraisal production data to determine the OOIP. VIP simulation models were generated to construct a development plan for this reservoir to determine the ultimate recovery. Significant uncertainties remained with regards to (1) location, number and type (horizontal vs vertical) of injectors, (2) number of producers to use, (3) geologic properties (in terms of correlation length and direction and facies distribution), and (4) fault transmissibility that could impact the choice of the plan of development (POD).
To select the optimal POD in terms of ultimate recovery a Top Down Reservoir Modeling1 (TDRM™) process was set up. Several 3D models were generated to cover the geologic uncertainty. The TDRM™ process analyzed 960 discrete combinations of the above parameters. An optimal POD was selected from the analysis of the results. The range of possible recovery outcomes was also more clearly quantified.
A development plan consisting of 1 horizontal injection well and 2 recompleted producing wells was chosen with an option to use two additional producers in the future. The injection well was drilled in early 2006 and the Southern Lobe of the PUT River began production in late 2006.
Optimizing Downhole Fluid Production of Sucker Rod Pumps Using Variable Motor Speed
Authors: Palka Krzysztof , Czyz Jaroslaw A. 
Published: March 2008

Abstract
Reciprocating oil pumps are traditionally operated by prime movers rotating at a constant speed. This paper demonstrates that by rapidly changing motor speed within a single stroke pump production can be increased while stresses in the sucker rod and motor energy consumption are reduced. The optimal motor speed profile is determined by representing the motor speed with Fourier series and searching for such Fourier coefficients that maximize the production while satisfying the imposed constraints on stresses in the rod and on energy consumption. The pump performance parameters required in the optimization process, such as fluid production, stresses in the rod and motor torque resulting from a given variable motor speed are calculated using a predictive analysis. The analysis is based on a comprehensive dynamic model of the entire pumping system comprising both surface and downhole equipment.
During, and beyond a minimum 6 month field validation period the calculated optimal speed profile has been applied to control the movement of over 20 pumps currently operating in Alberta, Canada. The resulting increased production and lower operating cost clearly confirmed the benefits of implementing a variable speed of the prime mover to improve pump performance. Presented examples demonstrate an increase of up to 133% in production without increasing energy consumption or loads in the system. Similar results as with beam pumps can be achieved for hydraulically actuated pumps by applying variable flow rate or pressure to induce the calculated optimal polished rod velocity.
A Novel Corrosion Resistant Internal Coating Method Using Hollow Cathode PECVD Technology with Improved Hardness
Authors: Boardman Bill , Bonapolly Karthik , Upadhayaya Deepak , Casserly Tom 
Published: March 2008

Abstract
A novel technology developed for coating the internal surfaces of parts from small components to production pipe will be described. The coating is appropriate for use in many environments for corrosion, erosion and wear reduction. The process technology that enables the coating of interior surfaces with a hard, wear and corrosion resistant DLC layer will be described. Additionally the development of improved hardness of the DLC will be decribed, based on the selection of precursor and process parameters hardness of &gt; 25GPa has been achived while maintaining a high deposition rate.
The Use of Pulsed Neutron Measurements for Determination of Bypassed Pay: A Multiwell Study
Authors: May Dale H. , Grant Jeffery , Pinto Keith Thomas 
Published: March 2008

Abstract
Pulsed neutron measurements have been used since the early 1960s to measure porosity and sigma through casing. Since the formation sigma response is proportional to the salinity of the formation water, pulsed neutron measurements are used to determine porosity and water saturation behind pipe.
In parts of west Texas and southern California, it is common to use through-casing pulsed neutron measurements for water and CO2 flood monitoring. By comparing time-lapse pulse neutron data, it is possible to determine changes over time in water, gas, and oil saturations.
The concepts and methodologies that allow time lapsed pulsed neutron measurements to be used for water and CO2 flood monitoring can be used to identify bypassed pay in fields that have been under only primary production.
In water and CO2 floods, the base pulsed neutron measurement is compared over time with subsequent pulsed neutron measurements. The changes in the pulsed neutron porosity and sigma measurements are related to changes in oil, gas, and water saturations.
Most producing wells do not have base pulsed neutron measurements. Many of these wells do have porosity and resistivity measurements that were acquired prior to setting casing.
There are many challenges faced when attempting to incorporate various pulsed neutron measurements with the original porosity and resistivity measurements for a consistent evaluation. This paper will present the methodology of incorporating the present day pulsed neutron measurements, with the original porosity and resistivity measurements into a comprehensive petrophysical model. This model will solve simultaneously for the original hydrocarbon in place, along with the current hydrocarbon in place.
This paper will show how the combination of pulsed neutron measurements and original open hole log data, on a multi-well basis, was used to identify bypassed hydrocarbons.
The bypassed pay was used to design a recompletion program and resulted in significant increases in both produced hydrocarbon and proven reserves of hydrocarbon.
Based on the increase of hydrocarbons found by bypassed pay analysis a re-completion program was designed and put into action that resulted in an increase of produced hydrocarbons and proven reserves of hydrocarbons.
Consequence of Thermophysical Approximations on Upstream Calculations: A Case Study
Authors: Pasala Sangeetha , Sen Sabyasachi , Gummadi Srividya , Kirchner Mike 
Published: March 2008

Abstract
Until recently, most Oil&Gas companies employed a combination of decentralized manual and computer-based methods, to meet their upstream calculation needs. Some of the majors even developed powerful in-house programs tailored to processes of interest. Recently, however, third-party computer applications (simulators) have become the de facto standard for most industry-wide calculations.
The quality of results obtained from a simulator depends strongly on simple semi-empirical thermophysical methods at its core. Most thermophysical methods implemented in the simulators have limited applicability, typically because these methods need to be simple to ensure robustness and speed, at the expense of accuracy. The other common limitation is the scarcity of measured data to validate model parameters. Typically, these simple models are unable to span wide ranges in pressure, temperature and composition (PTx), often encountered in upstream processes.