bluuebunny/crossref_metadata_2025_split huggingface dataset:
Inhalation anesthesia induced by isoflurane alters penicillin disposition in swine tissues
Authors: Chiesa O. A. , Heller D. N. , Karanian J. W. , Pritchard W. F. , Smith S. , Kijak P. J. , Ward J. L. , von Bredow J. , Myers M. J. 
Published: September 2016

Twelve healthy swine were dosed with penicillin G intramuscularly. Fluids and tissues samples were collected at the end of two periods of general anesthesia, performed 24 h apart. Tissue samples were collected by minimally invasive laparoscopy under general anesthesia at 8 and 28 h postdose. Four nonanesthetized, penicillin‐treated pigs were euthanized at 8 h postdose, and a second set of four similarly treated control pigs were sacrificed 28 h postdose. Liver penicillin tissue concentrations from animals that underwent anesthesia and laparoscopic tissue collection had tissue concentrations that were higher than nonanesthetized pigs at both time points. Urine, plasma, kidney, skeletal, and cardiac muscle showed no differences between the two groups. Laparoscopic tissue collection under general anesthesia in swine induces physiological changes that cause alterations in tissue pharmacokinetics not seen in conscious animals.
Residue depletion of amoxicillin and its major metabolites in eggs
Authors: Liu Y.‐N. , Pang M.‐D. , Xie X. , Xie K.‐Z. , Cui L.‐L. , Gao Q. , Liu J.‐Y. , Wang B. , Zhang Y.‐Y. , Wang R. , Zhang G.‐X. , Dai G.‐J. , Wang J.‐Y. 
Published: September 2016

The depletion of amoxicillin (AMO) and its major metabolites, amoxicilloic acid (AMA) and amoxicillin‐diketopiperazine‐2′,5′‐dione (DIKETO) in the albumen, yolk and whole egg was studied after the oral dose of AMO (25 and 50 mg/kg body weight) to laying hens once per day for five consecutive days. Egg samples were prepared by a simple liquid–liquid extraction procedure with acetonitrile and saturated methylene chloride and analysed using liquid chromatography–tandem mass spectrometry. The results showed that AMO, AMA and DIKETO residues were mainly distributed in the yolk, where particularly high concentrations of AMO and DIKETO were found, whereas the albumen contained high concentrations of AMA. This distribution suggested that AMO and DIKETO were depleted slowly in yolk, whereas AMA was depleted slowly in albumen. The amount of AMO residue positively correlated with the dose, and the theoretical withdrawal times, which were calculated based on the residue level falling below a safe limit, were 5.21 and 7.67 days at AMO doses of 25 and 50 mg/kg, respectively. Moreover, the theoretical withdrawal times for all residues in the whole egg were 8.00 and 9.11 days at doses of 25 and 50 mg/kg, respectively. Our findings suggested that 9 days was an appropriate withdrawal time for the use of AMO in laying hens.
Southeastern Pacific humpback whales (Megaptera novaeangliae) and their breeding grounds: Distribution and habitat preference of singers and social groups off the coast of Ecuador
Authors: Oña Javier , Garland Ellen C. , Denkinger Judith 
Published: September 2016

AbstractUnderstanding the distribution, habitat preference, and social structure of highly migratory species at important life history stages (e.g., breeding and calving) is essential for conservation efforts. We investigated the spatial distribution and habitat preference of humpback whale social groups and singers, in relation to depth categories (<20 m, 20–50 m, and >50 m) and substrate type (muddy and mixed) on a coastal southeastern Pacific breeding ground. One hundred and forty‐three acoustic stations and 304 visual sightings were made at the breeding ground off the coast of Esmeraldas, Ecuador. Spatial autocorrelation analysis suggested singers were not randomly distributed, and Neu's method and Monte Carlo simulations indicated that singers frequented depths of <20 m and mixed substrate. Singletons, and groups with a calf displayed a preference for shallower waters (0–20 m), while pairs and groups with a calf primarily inhabited mixed bottom substrates. In contrast, competitive groups showed no clear habitat preference and exhibited social segregation from other whales. Understanding the habitat preference and distribution of humpback whales on breeding and calving grounds vulnerable to anthropogenic disturbance provides important baseline information that should be incorporated into conservation efforts at a regional scale.
Leaf anatomy mediates coordination of leaf hydraulic conductance and mesophyll conductance to CO2 in Oryza
Authors: Xiong Dongliang , Flexas Jaume , Yu Tingting , Peng Shaobing , Huang Jianliang 
Published: September 2016

Summary

Leaf hydraulic conductance (Kleaf) and mesophyll conductance (gm) both represent major constraints to photosynthetic rate (A), and previous studies have suggested that Kleaf and gm is correlated in leaves. However, there is scarce empirical information about their correlation.

In this study, Kleaf, leaf hydraulic conductance inside xylem (Kx), leaf hydraulic conductance outside xylem (Kox), A, stomatal conductance (gs), gm, and anatomical and structural leaf traits in 11 Oryza genotypes were investigated to elucidate the correlation of H2O and CO2 diffusion inside leaves.

All of the leaf functional and anatomical traits varied significantly among genotypes. Kleaf was not correlated with the maximum theoretical stomatal conductance calculated from stomatal dimensions (gsmax), and neither gs nor gsmax were correlated with Kx. Moreover, Kox was linearly correlated with gm and both were closely related to mesophyll structural traits.

These results suggest that Kleaf and gm are related to leaf anatomical and structural features, which may explain the mechanism for correlation between gm and Kleaf.
Open Microcomedone Extraction Facilitated by Polarized Dermoscopy
Authors: Naimer Sody Abby 
Published: September 2016

Abstract:Microcomedonal lesions can be aesthetically and psychologically displeasing. The burden of comedones increases when considering their frequency and demand for time‐consuming attention. The objective of the current study was to describe a novel technique to facilitate open microcomedone extraction. The instrumentation used includes smartphone photography with dermatoscopy. The dermatoscope is an effective tool for diagnosing a broad range of dermatologic conditions. The polarized dermatoscope can facilitate execution of cutaneous procedures whenever magnification and optimal illumination are necessary. Its connection to a smartphone with a unique adapter enabled single‐handed examination of microcomedones. Under magnification with this unit, the involved lesions are photographed to clearly demonstrate the condition and achieve informed consent. The complete procedure can be recorded on video for documentation. In this case, four separate lesions of the left auricle of a young man were treated using direct pressure extraction. The procedure undertaken was rapid, convenient, and completed without any adverse sequelae. This procedure is recommended for similar cases using the dermatoscope, which does not require additional specific training and is readily available at no extra cost. This technique could be used in various dermatologic conditions.
Trends in Pediatric Laboratory‐Diagnosed Onychomycosis Between 2006 and 2014 in the Southwest of England
Authors: Wlodek Christina , Trickey Adam , de Berker David , Johnson Elizabeth 
Published: September 2016

AbstractThis is the largest study of laboratory‐diagnosed onychomycosis in England for children younger than 17 years. The most common (91.5%) cultured organism in this population was Trichophyton rubrum. Candida species were isolated only from fingernails, and the majority were from children younger than 5 years. Continued analysis of fungal pathogens is vital to identify changing trends.
PERFORMANCE OF NATURAL REFRIGERANTS IN TWO PHASE FLOW
Authors: Mohd Yunos Yushazaziah , Rosli Mohd Azhar , Mohd-Ghazali Normah , Pamitran Agus Sujiantro 
Published: September 2016

The search for alternative environmentally friendly refrigerants have never been so crucial with the increasing demand for effective cooling of increasing miniaturization of our heat exchanging devices in the ever expanding air-conditioning and refrigeration industry. Although propane (R290) and ammonia (R717), natural refrigerants, have been around for decades, their two-phase thermal performance in small channels has yet to be fully investigated. Predictions of the heat transfer using correlations developed based on past experimental data have shown poor agreements, with more correlations being developed to date. This research was done to investigate the optimized conditions for the two-phase boiling heat transfer coefficient of R290 and R717 where the contributions from nucleate boiling and forced convective are represented explicitly. Multi-objective Genetic Algorithm (MOGA) is utilized for the simultaneous maximization of nucleate boiling and forced convective, two conflicting phenomena – the former generally significant in the low vapor quality region while the latter in the high quality region. A superposition correlation is used as it sums up both contributions. Two phased-out refrigerants, R134a and R22 are also being research here for comparison purposes. The range of MOGA design parameters set for mass flux, G, is between 100 - 300 kg/m2.s, heat flux q between 5 - 30 kW/m2 and vapor quality, x for 0.0009 - 0.9. The optimization is done for 3 mm channel diameter with saturation temperature at 10˚C. The optimized results showed a strong contribution of each nucleate boiling and forced convective for R717 with increasing vapor quality, compared to the other three refrigerants. The optimized value of the total heat transfer coefficient for R717 could reach up to 90 kW/m2.K and for R290 up to 12 kW/m2.K compared to R134a and R22 at 6 kW/m2.K and 5 kW/m2.K respectively. At lower vapor quality, the nucleate boiling contributes more to the total heat transfer coefficient, and suppressed due to forced convective as the vapor quality reaches middle range. The theoretical results indicate the potential of R717 and R290 as replacement refrigerants for R22 and R134a with further verifications to be done with correlations not using the superposition method.
Effects of fatigue on corticospinal excitability of the human knee extensors
Authors: Kennedy David S. , McNeil Chris J. , Gandevia Simon C. , Taylor Janet L. 
Published: September 2016

New Findings
What is the central question of this study?
Do group III and IV muscle afferents act at the spinal or cortical level to affect the ability of the central nervous system to drive quadriceps muscles during fatiguing exercise?
What is the main finding and its importance?
The excitability of the motoneurone pool of vastus lateralis was unchanged by feedback from group III and IV muscle afferents. In contrast, feedback from these afferents may contribute to inhibition at the cortex. However, the excitability of the corticospinal pathway was not directly affected by feedback from these afferents. These findings are important for understanding neural processes during fatiguing exercise.
In upper limb muscles, changes in afferent feedback, motoneurone excitability, and motor cortical output can contribute to failure of the central nervous system to recruit muscles fully during fatigue. It is not known whether similar changes occur with fatigue of muscles in the lower limb. We assessed the corticospinal pathway to vastus lateralis during fatiguing sustained maximal voluntary contractions (MVCs) of the knee extensors and during firing of fatigue‐sensitive group III/IV muscle afferents maintained by postexercise ischaemia after fatiguing MVCs of the knee extensors and, separately, the flexors. In two experiments, subjects (n = 9) performed brief knee extensor MVCs before and after 2‐min sustained MVCs of the knee extensors (experiment 1) or knee flexors (experiment 2). During MVCs, motor evoked potentials (MEPs) were elicited by transcranial magnetic stimulation over the motor cortex and thoracic motor evoked potentials (TMEPs) by electrical stimulation over the thoracic spine. During the 2‐min extensor contraction, the size of vastus lateralis MEPs normalized to the maximal M‐wave increased (P < 0.05), but normalized TMEPs were unchanged (P = 0.16). After the 2‐min MVC, maintained firing of group III/IV muscle afferents had no effect on vastus lateralis MEPs or TMEPs (P = 0.18 and P = 0.50, respectively). Likewise, after the 2‐min knee flexor MVC, maintained firing of these afferents showed no effect on vastus lateralis MEPs or TMEPs (P = 0.69 and P = 0.34, respectively). Motoneurones of vastus lateralis do not become less excitable during fatiguing isometric MVCs. Moreover, fatigue‐sensitive group III/IV muscle afferents fail to affect the overall excitability of vastus lateralis motoneurones during MVCs.
Comparison of Methanol and Kerosene Combustion in a Swirl Stabilized Spray Combustor
Authors: Levy Y. , Erenburg V. , Roizman A. , Sherbaum V. , Ovcharenko V. 
Published: September 2016

In contrast to other alternative fuels, methanol offers a plethora of advantages; it can be produced from natural gas, coal or any organic biomass matter. Methanol is the cheapest of all alternative fuels and has a reduced likelihood of reacting to form pollutants such as soot, CO, NOx. Furthermore, methanol is a liquid at standard atmospheric conditions and can be stored and transported much more cheaply and safely than gaseous fuel. There are also drawbacks that impinge on its overall utility: Methanol has a lower energy density as compared to conventional fossil liquid fuels (kerosene, diesel oil etc.), it has the propensity to react to form aldehyde emissions and to dissolve in atmospheric moisture. Methanol also has a low vapor pressure that could lead to cold start problems in IC engines, at temperatures below 15°C. The objective of the present work is to perform an experimental investigation and a chemical kinetic comparison of combustion characteristics between methanol and kerosene & diesel fueled swirl stabilized burner. A special emphasis is given to the impact of fuel conversion of existing combustion systems from kerosene (or diesel) to methanol.
The experimental set-up is based on a modified industrial burner with heating power of 50kW. In order to have a better control over the incoming air flow, the original blower is replaced with a larger and more stable industrial blower that allowed precise monitoring of the air flow rate. The combustion chamber consists of a stainless steel tube, 10cm in diameter and 80cm in length. The experiments include measurements of temperature distribution inside the combustor: wall temperature distribution is recorded with the use of thermocouples and a calibrated infra-red camera. The composition of the combustion pollutants is also monitored at the exhaust. A National Instruments cRIO 9074 controller is used in conjunction with a National Instruments LabView interface for data acquisition. The comparison between methanol and kerosene characteristics is carried out for equal heat release and equivalence ratios.
Experimental results show that methanol burns slower than kerosene and therefore requires a longer combustor. It is found that the larger methanol droplet size and its larger volume flux contribute significantly to this extended length requirement for complete methanol combustion. The measured CO emission values for kerosene and methanol were 25 and 110 ppm respectively, and 40 and 10ppm for NOx. These results clearly indicate the reduced NOx emission during methanol combustion; however, the notable presence of CO indicates that methanol needs a longer combustor length to complete the combustion process.
Effect of Exit Pressure Pulsation on the Performance and Stability Limit of a Turbocharger Centrifugal Compressor
Authors: Barrera-Medrano Maria Esperanza , Newton Peter , Martinez-Botas Ricardo , Rajoo Srithar , Tomita Isao , Ibaraki Seiichi 
Published: September 2016

It is well known that compressor surge imposes a significant limit on the flow range of a turbocharged internal combustion engine. The centrifugal compressor is commonly placed upstream of the inlet manifold and hence, it is exposed to the intermittent flow regime of the inlet valves. Surge phenomena has been well studied over the past decades, there still remains limited information with regards to the unsteady impact caused by the inlet valves. This study presents an experimental evaluation of such a situation. Engine representative pulses are created by a downstream system comprising a large volume, two rotating valves, a throttle valve and the corresponding pipe network. Different pulsation levels are characterized by means of their frequency and the corresponding amplitude at the compressor inlet.
The stability limit of the system under study is evaluated with reference to the parameter B proposed by Greitzer [7–9]. B describes the dynamics of the compression system in terms of volume, area, equivalent length and compressor tip speed as well as the Helmholtz frequency of the system. For a given compressor, as B goes beyond a critical value, the system will exhibit surge as the result of the flow instability progression.
The reduced frequency analysis shows that the scroll-diffuser operates in an unsteady regime, while the impeller is nearly quasi-steady. In the vicinity of the surge point, under a pulsating flow, the instantaneous operation of the compressor showed significant excursions into the unstable side of the surge line. Furthermore, it has been found that the presence of a volume in the system has the greatest effect on the surge margin of the compressor under the unsteady conditions.
Coke Deposition Effect on the Flow Distribution Characteristics of Kerosene Under Supercritical Pressure
Authors: Huang H. R. , Deng H. W. , Xu G. Q. , Jia Z. X. , Fu Y. C. 
Published: September 2016

Performed experiments have studied the effect of coke deposition on the characteristics of flow distribution of aviation kerosene RP-3 at supercritical pressure. The whole experiment is divided into two steps: 1) making a coke tube; 2) paralleling the coked tube and a regular one with the same scale and observing the flow distribution status in different system pressure and total mass flow rate. The experimental results indicated that the deposition of coke made a great difference on the flow distribution of fuel.
Based on experimental results, it’s demonstrated that the percentage of total mass flow rate in coke-free tube increases to 68.5%. Further analyses reveal the fact that the total mass flow rate has nearly no impact on flow distribution and the system pressure also influence the distribution very little. What’s more, the amount of coke vs axial position and total amount of coke in coked tube are mentioned in this paper, which is benefit in analysis of flow distribution.
Prediction of Confined Flame Flashback Limits Using Boundary Layer Separation Theory
Authors: Hoferichter Vera , Hirsch Christoph , Sattelmayer Thomas 
Published: September 2016

Premixed combustion is a common technology applied in modern gas turbine combustors to minimize nitrogen oxide emissions. However, early mixing of fuel and oxidizer opens up the possibility of flame flashback into the premixing section upstream of the combustion chamber. Especially for highly reactive fuels boundary layer flashback is a serious challenge. For high preheating and burner surface temperatures, boundary layer flashback limits for burner stabilized flames converge to those of so-called confined flames, where the flame is stabilized inside the burner duct. Hence, the prediction of confined flashback limits is a highly technically relevant task.
In this study, a predictive model for flashback limits of confined flames is developed for premixed hydrogen-air mixtures. As shown in earlier studies, confined flashback is initiated by boundary layer separation upstream of the flame tip. Hence, the flashback limit can be predicted identifying the minimum pressure rise upstream of a confined flame causing boundary layer separation. For this purpose, the criterion of Stratford is chosen which was originally developed for boundary layer separation in mere aerodynamic phenomena. It is shown in this paper that it can also be applied to near wall combustion processes if the pressure rise upstream of the flame tip is modeled correctly. In order to determine the pressure rise, an expression for the turbulent burning velocity is derived including the effects of flame stretch and turbulence. A comparison of the predicted flashback limits and experimental data shows high prediction accuracy and wide applicability of the developed model.
A Laboratory Based Course on Energy Systems in Mechanical Engineering Undergraduate Program
Authors: Deniz Sabri 
Published: September 2016

A laboratory based undergraduate course focused on energy systems and energy efficiency was developed at the Lucerne University of Applied Sciences. The course is a practice-oriented introduction to fluid / energy systems, turbomachinery, and energy production. It is offered to the mechanical engineering as well as to the “Energy Systems” program students in the first semester. Main parts of the course are experiments and mini projects carried out in the fluid mechanics, thermodynamics, and turbomachinery laboratories. After an introduction of (1) the basic theory of the mass- and energy conservation equations as main governing laws for energy systems and (2) measurement techniques during the first two weeks, the students carry out experiments in small groups on different test rigs with the help of an instructor for about four weeks (each week a different test). The experiments and test rigs are selected considering different aspects of turbomachinery and energy systems. They cover hydraulic turbines, small wind turbines, a water pump, compressor, heat pump, combined heat and power system, fuel cell, solar energy, and combustion engine. Following a two weeks theory wrap up, the students start with mini projects again in small groups in the laboratory. The students are requested to do a new design or to carry out a design change or modification at an existing machine or test rig. They also need to test their new design or design modification. At the end the students have to do a presentation about the mini project results and write a short report.
The objectives of the course are first to introduce the laboratory environment to the students from the beginning of the curriculum. Further the experimental investigations on laboratory test rigs make the students familiar with the fundamentals, working principles, characteristics, operation, and application of turbomachinery and energy systems. They also learn the basics of energy conversion, conservation, and the importance of relevant performance parameters such as efficiency. The mini projects have direct practical relevance to real world problems and applications. From an educational viewpoint the students are introduced to team-work during the projects, project planning with execution, and they are learning by doing or by experiential learning. The students are actively involved in the mini projects and they can reflect their experience at the end of the course during the presentations. The implementation of the course is time consuming and costly but the feedback from the students is very positive although they are challenged by confronting real world energy systems and problems in the first semester.