bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential induction of polar and non‐polar metabolism during wound‐induced suberization in potato (Solanum tuberosum L.) tubers
Authors: Woolfson Kathlyn N. , Haggitt Meghan L. , Zhang Yanni , Kachura Alexandra , Bjelica Anica , Rey Rincon M. Alejandra , Kaberi Karina M. , Bernards Mark A.
Published: January 2018

Wound‐induced suberin deposition involves the temporal and spatial coordination of phenolic and fatty acid metabolism. Phenolic metabolism leads to both soluble metabolites that accumulate as defense compounds as well as hydroxycinnamoyl derivatives that form the basis of the poly(phenolic) domain found in suberized tissue. Fatty acid metabolism involves the biosynthesis of very‐long‐chain fatty acids, 1‐alkanols, ω‐hydroxy fatty acids and α,ω‐dioic acids that form a poly(aliphatic) domain, commonly referred to as suberin. Using the abscisic acid (ABA) biosynthesis inhibitor fluridone (FD), we reduced wound‐induced de novo biosynthesis of ABA in potato tubers, and measured the impact on the expression of genes involved in phenolic metabolism (StPAL1, StC4H, StCCR, StTHT), aliphatic metabolism (StCYP86A33, StCYP86B12, StFAR3, StKCS6), metabolism linking phenolics and aliphatics (StFHT) or acyl chains and glycerol (StGPAT5, StGPAT6), and in the delivery of aliphatic monomers to the site of suberization (StABCG1). In FD‐treated tissue, both aliphatic gene expression and accumulation of aliphatic suberin monomers were delayed. Exogenous ABA restored normal aliphatic suberin deposition in FD‐treated tissue, and enhanced aliphatic gene expression and poly(aliphatic) domain deposition when applied alone. By contrast, phenolic metabolism genes were not affected by FD treatment, while FD + ABA and ABA treatments slightly enhanced the accumulation of polar metabolites. These data support a role for ABA in the differential induction of phenolic and aliphatic metabolism during wound‐induced suberization in potato.
Maize w3 disruptshomogentisate solanesyl transferase (ZmHst) and reveals a plastoquinone‐9 independent path for phytoene desaturation and tocopherol accumulation in kernels
Authors: Hunter Charles T. , Saunders Jonathan W. , Magallanes‐Lundback Maria , Christensen Shawn A. , Willett Denis , Stinard Philip S. , Li Qin‐Bao , Lee Kwanghee , DellaPenna Dean , Koch Karen E.
Published: January 2018

Maizewhite seedling 3(w3) has been used to study carotenoid deficiency for almost 100 years, although the molecular basis of the mutation has remained unknown. Here we show that thew3phenotype is caused by disruption of the maize gene for homogentisate solanesyl transferase (HST), which catalyzes the first and committed step in plastoquinone‐9 (PQ‐9) biosynthesis in the plastid. The resultingPQ‐9 deficiency prohibits photosynthetic electron transfer and eliminatesPQ‐9 as an oxidant in the enzymatic desaturation of phytoene during carotenoid synthesis. As a result, light‐grownw3seedlings are albino, deficient in colored carotenoids and accumulate high levels of phytoene. However, despite the absence ofPQ‐9 for phytoene desaturation, dark‐grownw3seedlings can produce abscisic acid (ABA) and homozygousw3kernels accumulate sufficient carotenoids to generateABAneeded for seed maturation. The presence ofABAand low levels of carotenoids inw3nulls indicates that phytoene desaturase is able to use an alternate oxidant cofactor, albeit less efficiently thanPQ‐9. The observation that tocopherols and tocotrienols are modestly affected inw3embryos and unaffected inw3endosperm indicates that, unlike leaves, grain tissues deficient inPQ‐9 are not subject to severe photo‐oxidative stress. In addition to identifying the molecular basis for the maizew3mutant, we: (1) show that low levels of phytoene desaturation can occur inw3seedlings in the absence ofPQ‐9; and (2) demonstrate thatPQ‐9 and carotenoids are not required for vitamin E accumulation.
Transfusion support for transgender men of childbearing age
Authors: Mays James A. , Greene Dina N. , Metcalf Ryan A. , Pagano Monica B.
Published: January 2018

BACKGROUND

To date, limited attention has been given to transgender recipients of blood components, particularly transgender men of childbearing age. Here, we highlight the essential information needed to provide transfusion support for this population.

CASE REPORT

A 40‐year‐old transgender man, who retained his uterus and ovaries, presented with severe vaginal hemorrhage following biopsies for a cervical mass. He was admitted to the Gynecology unit and emergency blood was ordered. Because the patient was listed as male in the electronic health record (EHR), the transfusion service prepared uncrossmatched type O, RhD‐positive red blood cells (RBC). After the sex/gender incongruence was recognized, the units were switched for Rh‐negative.

CONCLUSION

This case illustrates particular considerations when caring for transgender patients: gender/sex documentation, decision‐making processes when gender/sex‐specific care applies, and challenges to the pathology service.
Voltage‐gated sodium channels: (NaV)igating the field to determine their contribution to visceral nociception
Authors: Erickson Andelain , Deiteren Annemie , Harrington Andrea M. , Garcia‐Caraballo Sonia , Castro Joel , Caldwell Ashlee , Grundy Luke , Brierley Stuart M.
Published: January 2018

Chronic visceral pain, altered motility and bladder dysfunction are common, yet poorly managed symptoms of functional and inflammatory disorders of the gastrointestinal and urinary tracts. Recently, numerous human channelopathies of the voltage‐gated sodium (NaV) channel family have been identified, which induce either painful neuropathies, an insensitivity to pain, or alterations in smooth muscle function. The identification of these disorders, in addition to the recent utilisation of genetically modified NaVmice and specific NaVchannel modulators, has shed new light on how NaVchannels contribute to the function of neuronal and non‐neuronal tissues within the gastrointestinal tract and bladder. Here we review the current pre‐clinical and clinical evidence to reveal how the nine NaVchannel family members (NaV1.1–NaV1.9) contribute to abdominal visceral function in normal and disease states.

image
The large‐conductance voltage‐ and Ca2+‐activated K+ channel and its γ1‐subunit modulate mouse uterine artery function during pregnancy
Authors: Lorca Ramón A. , Wakle‐Prabagaran Monali , Freeman William E. , Pillai Meghan K. , England Sarah K.
Published: January 2018

Key points

The uterine artery (UA) markedly vasodilates during pregnancy to direct blood flow to the developing fetus. Inadequate UA vasodilatation leads to intrauterine growth restriction and fetal death.

The large‐conductance voltage‐ and Ca2+‐activated K+ (BKCa) channel promotes UA vasodilatation during pregnancy.

We report that BKCa channel activation increases the UA diameter at late pregnancy stages in mice.

Additionally, a BKCa channel auxiliary subunit, γ1, participates in this process by increasing channel activation and inducing UA vasodilatation at late pregnancy stages.

Our results highlight the importance of the BKCa channel and its γ1‐subunit for UA functional changes during pregnancy.

Insufficient vasodilatation of the uterine artery (UA) during pregnancy leads to poor utero‐placental perfusion, contributing to intrauterine growth restriction and fetal loss. Activity of the large‐conductance Ca2+‐activated K+ (BKCa) channel increases in the UA during pregnancy, and its inhibition reduces uterine blood flow, highlighting a role of this channel in UA adaptation to pregnancy. The auxiliary γ1‐subunit increases BKCa activation in vascular smooth muscle, but its role in pregnancy‐associated UA remodelling is unknown. We explored whether the BKCa and its γ1‐subunit contribute to UA remodelling during pregnancy. Doppler imaging revealed that, compared to UAs from wild‐type (WT) mice, UAs from BKCa knockout (BKCa−/−) mice had lower resistance at pregnancy day 14 (P14) but not at P18. Lumen diameters were twofold larger in pressurized UAs from P18 WT mice than in those from non‐pregnant mice, but this difference was not seen in UAs from BKCa−/− mice. UAs from pregnant WT mice constricted 20–50% in response to the BKCa blocker iberiotoxin (IbTX), whereas UAs from non‐pregnant WT mice only constricted 15%. Patch‐clamp analysis of WT UA smooth muscle cells confirmed that BKCa activity increased over pregnancy, showing three distinct voltage sensitivities. The γ1‐subunit transcript increased 7‐ to 10‐fold during pregnancy. Furthermore, γ1‐subunit knockdown reduced IbTX sensitivity in UAs from pregnant mice, whereas γ1‐subunit overexpression increased IbTX sensitivity in UAs from non‐pregnant mice. Finally, at P18, γ1‐knockout (γ1−/−) mice had smaller UA diameters than WT mice, and IbTX‐mediated vasoconstriction was prevented in UAs from γ1−/− mice. Our results suggest that the γ1‐subunit increases BKCa activation in UAs during pregnancy.
Muscle molecular adaptations to endurance exercise training are conditioned by glycogen availability: a proteomics‐based analysis in the McArdle mouse model
Authors: Fiuza‐Luces Carmen , Santos‐Lozano Alejandro , Llavero Francisco , Campo Rocío , Nogales‐Gadea Gisela , Díez‐Bermejo Jorge , Baladrón Carlos , González‐Murillo África , Arenas Joaquín , Martín Miguel A. , Andreu Antoni L. , Pinós Tomàs , Gálvez Beatriz G. , López Juan A. , Vázquez Jesús , Zugaza José L. , Lucia Alejandro
Published: January 2018

Key points

Although they are unable to utilize muscle glycogen, McArdle mice adapt favourably to an individualized moderate‐intensity endurance exercise training regime. Yet, they fail to reach the performance capacity of healthy mice with normal glycogen availability.

There is a remarkable difference in the protein networks involved in muscle tissue adaptations to endurance exercise training in mice with and without glycogen availability.

Indeed, endurance exercise training promoted the expression of only three proteins common to both McArdle and wild‐type mice: LIMCH1, PARP1 and TIGD4.

In turn, trained McArdle mice presented strong expression of mitogen‐activated protein kinase 12 (MAPK12).

McArdle's disease is an inborn disorder of skeletal muscle glycogen metabolism that results in blockade of glycogen breakdown due to mutations in the myophosphorylase gene. We recently developed a mouse model carrying the homozygous p.R50X common human mutation (McArdle mouse), facilitating the study of how glycogen availability affects muscle molecular adaptations to endurance exercise training. Using quantitative differential analysis by liquid chromatography with tandem mass spectrometry, we analysed the quadriceps muscle proteome of 16‐week‐old McArdle (n = 5) and wild‐type (WT) (n = 4) mice previously subjected to 8 weeks’ moderate‐intensity treadmill training or to an equivalent control (no training) period. Protein networks enriched within the differentially expressed proteins with training in WT and McArdle mice were assessed by hypergeometric enrichment analysis. Whereas endurance exercise training improved the estimated maximal aerobic capacity of both WT and McArdle mice as compared with controls, it was ∼50% lower than normal in McArdle mice before and after training. We found a remarkable difference in the protein networks involved in muscle tissue adaptations induced by endurance exercise training with and without glycogen availability, and training induced the expression of only three proteins common to McArdle and WT mice: LIM and calponin homology domains‐containing protein 1 (LIMCH1), poly (ADP‐ribose) polymerase 1 (PARP1 – although the training effect was more marked in McArdle mice), and tigger transposable element derived 4 (TIGD4). Trained McArdle mice presented strong expression of mitogen‐activated protein kinase 12 (MAPK12). Through an in‐depth proteomic analysis, we provide mechanistic insight into how glycogen availability affects muscle protein signalling adaptations to endurance exercise training.
Ageing of the carotid body
Authors: Di Giulio Camillo
Published: January 2018

The ageing process is characterized by a decline in several physiological functions resulting in a reduced capability to maintain homeostasis. The lowered homeostatic capacity seems to involve the carotid body (CB), whose role is to modulate ventilation and tissue oxygen supply. It thus plays a prime role in all ageing processes. Ageing causes marked changes in CB morphology. In older animals, it is enlarged and shows a concomitant decrease in the percentage of chemoreceptor tissue, as well as a proliferation of type II cells. The carotid glomitis is present with aggregates of lymphocytes and fibrosis of the lobules. Type I cells are dehydrated, with a profound vacuolization, a shrinking nucleus, and lipofuscin accumulation. With increased age, human CB shows a reduction in the number and volume of mitochondria, fewer synaptic junctions between glomi, along with a reduction in CB content of neurotransmitters, leading to a sort of ‘physiological denervation’. Ageing could be interpreted as a cumulative result of oxidative damage to cells, which derives from aerobic metabolism. Moreover, metabolic rate is tightly correlated with life duration; thus a loss in mitochondrial function is one of the prime factors affecting CB ageing processes. The age‐related reduction in synaptic junctions might be a self‐protective mechanism through which cells buffer themselves against an accumulation of reactive oxygen species. The correlation between hypoxia and the life duration of CB cells remains an open question until how and why cells sense oxygen is understood.
HCN4 pacemaker channels attenuate the parasympathetic response and stabilize the spontaneous firing of the sinoatrial node
Authors: Kozasa Yuko , Nakashima Noriyuki , Ito Masayuki , Ishikawa Taisuke , Kimoto Hiroki , Ushijima Kazuo , Makita Naomasa , Takano Makoto
Published: January 2018

Key points

The contribution of HCN4 pacemaker channels in the autonomic regulation of the sino‐atrial node (SAN) has been a matter of debate.

The transgenic overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability, while the conditional knockdown of HCN4 gave rise to sinus arrhythmia.

The response of the SAN to β‐adrenergic stimulation was not affected by overexpression or knockdown of HCN4 channels.

When HCN4 channels were knocked down, the parasympathetic response examined by cervical vagus nerve stimulation (CVNS) was enhanced; the CVNS induced complete sinus pause. The overexpression of HCN4 attenuated bradycardia induced by CVNS only during β‐adrenergic stimulation.

We concluded that HCN4 pacemaker channels stabilize the spontaneous firing by attenuating the parasympathetic response of the SAN.

The heart rate is dynamically controlled by the sympathetic and parasympathetic nervous systems that regulate the sinoatrial node (SAN). HCN4 pacemaker channels are the well‐known causative molecule of congenital sick sinus syndrome. Although HCN4 channels are activated by cAMP, the sympathetic response of the SAN was preserved in patients carrying loss‐of‐function mutations of the HCN4 gene. In order to clarify the contribution of HCN4 channels in the autonomic regulation of the SAN, we developed novel gain‐of‐function mutant mice in which the expression level of HCN4 channels could be reversibly changed from zero to ∼3 times that in wild‐type mice, using tetracycline transactivator and the tetracycline responsive element. We recorded telemetric ECGs in freely moving conscious mice and analysed the heart rate variability. We also evaluated the response of the SAN to cervical vagus nerve stimulation (CVNS). The conditional overexpression of HCN4 did not induce tachycardia, but reduced heart rate variability. The HCN4 overexpression also attenuated bradycardia induced by the CVNS only during the β‐adrenergic stimulation. In contrast, the knockdown of HCN4 gave rise to sinus arrhythmia, and enhanced the parasympathetic response; complete sinus pause was induced by the CVNS. In vitro, we compared the effects of acetylcholine on the spontaneous action potentials of single pacemaker cells, and found that similar phenotypic changes were induced by genetic manipulation of HCN4 expression both in the presence and absence of β‐adrenergic stimulation. Our study suggests that HCN4 channels attenuate the vagal response of the SAN, and thereby stabilize the spontaneous firing of the SAN.
Assessment of the Robustness of a Fixtureless Inspection Method for Nonrigid Parts Based on a Verification and Validation Approach
Authors: Karganroudi Sasan Sattarpanah , Cuillière Jean-Christophe , François Vincent , Tahan Souheil-Antoine
Published: January 2018

The increasing practical use of computer-aided inspection (CAI) methods requires assessment of their robustness in different contexts. This can be done by quantitatively comparing estimated CAI results with actual measurements. The objective is comparing the magnitude and dimensions of defects as estimated by CAI with those of the nominal defects. This assessment is referred to as setting up a validation metric. In this work, a new validation metric is proposed in the case of a fixtureless inspection method for nonrigid parts. It is based on using a nonparametric statistical hypothesis test, namely the Kolmogorov–Smirnov (K–S) test. This metric is applied to an automatic fixtureless CAI method for nonrigid parts developed by our team. This fixtureless CAI method is based on calculating and filtering sample points that are used in a finite element nonrigid registration (FENR). Robustness of our CAI method is validated for the assessment of maximum amplitude, area, and distance distribution of defects. Typical parts from the aerospace industry are used for this validation and various levels of synthetic measurement noise are added to the scanned point cloud of these parts to assess the effect of noise on inspection results.
Diesel Engine Performance Improvement for Constant Speed Application Using CFD
Authors: Dahifale Balasaheb S. , Patil Anand S.
Published: January 2018

The detailed investigation of flow behavior inside the combustion chamber and performance of engine is most challenging problem due to constraints in Experimental Data collection during testing; However, Experimental testing is essential for establishment of correlation with CFD Predictions. Hence, the baseline engine was tested at different load conditions and validated with CFD results, before it was optimized for performance improvement. The objective of the CFD Prediction was not only to optimize performance (Fuel Efficiency, Power, Torque, etc.) & Emissions Reduction, but also to assess feasibility of Performance Upgrade Potential.

In the present CFD study, surface mesh and domain was prepared for the flame face, intake valve, intake valve seat, exhaust valve, exhaust valve seat and liner for closed volume cycle, between IVC and EVO using CFD code VECTIS. Finally simulations for three different load conditions were conducted using VECTIS solver. Initially, in-cylinder pressure vis a vis crank angle prediction was carried out for 100%, 75% and 50% load conditions. Then the fine tuning of (P-ϴ) diagram for different load conditions was conducted by varying different combustion parameters. Further, the engine performance validation was carried out for rated and part load conditions in terms of, IMEP, BMEP, break specific fuel consumption and power output, while NOx mass fractions were used to convert the NOx to g/kWh for comparison of emission levels with the test data. Finally optimized re-entrant combustion chamber and modified valve timing with optimum fuel injection system simulation was carried out to achieve target performance with reduced fuel consumption. A 3D CFD result showed reduction in BSFC and was in close agreement with the test data.
Sublimation Rate of Vertically Oriented Naphthalene Cylinders in Natural Convection
Authors: Carley Lauren , Janna William S. , Marchetta Jeffrey
Published: January 2018

The naphthalene sublimation technique was used to determine the rate of mass transfer from three solid naphthalene cylinders in a natural convection environment. The cylinder diameters measured 2.5 cm (1 in), 3.8 cm (1.5 in), and 5 cm (2 in) nominally. Sublimation rates were measured and the mass transfer coefficients were calculated. Correlations were developed for the Sherwood vs. Rayleigh numbers, Sherwood vs. Grashof numbers, and mass transfer coefficient vs. diameter.
Numerical Investigation of Flow Through an Ultra-Micro Scale Gas Turbine
Authors: D’souza Rohann , Sharma Rajnish
Published: January 2018

The ultra-micro scale gas turbine (UMGT) is an ongoing area of research, as an alternate power source for portable electronic devices. To advance our understanding that will help in its development, this paper focuses on a numerical analysis via computational fluid dynamics (CFD) of flow through a 3 dimensional (3D) blade profiled UMGT turbine. CFD modelling was based off an integrated turbine that consists of a volute, nozzle guide vanes (NGV) and rotor. Firstly, the flow through the integrated system as well as each component was analyzed. Secondly, the turbine was simulated under three different isothermal conditions and compared to the adiabatic situation, in order to understand the loss mechanisms. Lastly, the effect of tip clearance was studied, where it was varied between 0–10% of the blade height.

CFD results showed, the flow through the turbine was quite well behaved, however separation of flow at the NGV leading edge, and residual swirl at the rotor trailing edge, were observed. The effects of the isothermal wall boundary condition was very pronounced at the volute and NGV, resulting in a large amount of good heat to be conducted away, at the rotor however conduction was only a percentage of the viscous heat generated. Lastly tip clearance proved to have a linearly detrimental effect on power.
Mechanical Energy Absorption in Polyethylene Cell Pattern Structures for Biomedical Uses
Authors: Corro-Hernández Humberto , Vidal-Lesso Agustín , Ledesma-Orozco Elías R.
Published: January 2018

Energy absorption and dissipation are characteristics that can be used to protect and extend the useful life of many systems. Two new models of shock absorption structures are proposed. These are based on honeycomb cell patterns with inherent negative stiffness, in theory enabling a large amplification of their damping and recoverability capabilities within a limited space.

A 2D finite element analysis (FEA) is carried on as a first approach for testing this concept. The reduction of kinetic energy of a falling block above the structure is taken as the main indicator of energy absorption.

After some verifications 3D models are developed and tested analogously. Numerical results are obtained with polyethylene (PE) material properties, looking forward for development of future applications in biomechanics.
A Study on the Effects of Strain Rates on Characteristics of Brain Tissue
Authors: Hosseini Farid Mohammad , Eslaminejad Ashkan , Ziejewski Mariusz , Karami Ghodrat
Published: January 2018

Traumatic brain injury (TBI) often happens when the brain tissue undergoes a high rate mechanical load. Although numerous research works have been carried out to study the mechanical characterization of brain matter under quasi-static (strain rate ≤ 100 S−1) loading but a limited amount of experimental studies are available for brain tissue behavior under dynamic strain rates (strain rate ≥ 100 S−1). In this paper, the results of a study on mechanical properties of ovine brain tissue under unconfined compression tests are to be presented. The samples were compressed under uniaxial strain rates of 0.0667, 3.33, 6.667, 33.33, 66.667 and 200 S−1. The brain tissue presents a stiffer response with increasing strain rate, showing a time-dependent behavior. So the hyperelastic-only models are not adequate to exhibit the brain viscoelasticity. Therefore, two hyper-viscoelastic constitutive equations based on power function model and Mooney-Rivlin energy function are applied to the results with quasi-static strain rate (≤ 100 S−1). Good agreement of experimental and theoretical has been achieved for results of the low strain rates. It is concluded that the obtained material parameters from quasi-static tests are not appropriate enough to fit the result with the high strain rate of 200 S−1. The study will further provide new insight into a better understanding of the rate-dependency behavior of the brain tissue under dynamic conditions. This is essential in the development of constitutive material characteristics for an efficient human brain finite element models to predict TBI under impact condition or high motion.
Modeling and Experimental Investigations of Drill Pipe Failure
Authors: Abdo Jamil , Hassan Edris M. , Boulbrachene Khaled , Kwak Jan
Published: January 2018

During drilling operations, drill string interacts continuously with rock formation, which result in severe shock and vibrations. Lateral, torsion and axial vibration modes often cause failures of Bottom Hole Assembly (BHA), drill pipe abrasive wear, drill bit and wall borehole damages. It also leads to reduction in Rate of Penetration (ROP) and consequently incur unnecessarily high costs. The Lagrangian approach has been used in this study to attain drill pipe lateral and torsional vibration coupling equations of motion. The mathematical model is expressed in terms of four independent degrees of freedom. The effects of bending and torsion vibrations, and whirling motion of the drill string are incorporated in the developed model. A set of nonlinear equations are solved numerically to obtain the response of the system. In this work, we also present a brief description of an in-house constructed experimental setup. The setup has the capability to imitate the downhole axial, lateral and torsional vibration modes and mechanisms. Experimental investigations for the drill pipe fatigue failure due to lateral and torsional cyclic stresses induced in the drill string are also presented. Such investigations are essential for oil/gas industry as they provide solutions for very common problems such as drill string fatigue failure. The performance of the setup was validated. Numbers of tests were performed to investigate the effects of rotational speeds on the vibration amplitudes of different drill string sizes.
Stress-Induced Change of the Microstructure and Strength of Modified 9Cr-1Mo Steel Under Fatigue and Creep Loadings at Elevated Temperatures
Authors: Shinozaki Taichi , Suzuki Ken , Miura Hideo
Published: January 2018

The change of the lath martensitic structure in modified 9Cr-1Mo steel was observed in the specimens after the fatigue and creep tests using EBSD (Electron Back-Scatter Diffraction). The Kernel Average Misorientation (KAM) value obtained from the EBSD analysis were used for the quantitative evaluation of the change in the lath martensitic texture. It was found that the average KAM values of the fractured specimens decreased clearly after 107−108 cycles of the fatigue loading at temperatures higher than 500°C when the amplitude of the applied stress exceeded a critical value. This change corresponded to the disappearance of the lath martensitic structure. The critical value decreased monotonically with the increase of the test temperature. This microstructure change decreased the strength of the alloy drastically.

It was found that the change of the microstructure started at a certain time at each test temperature as a function of the amplitude of the applied stress. There was the critical stress at which the microstructure change started at each test temperature higher than 500°C, and the activation energy of the change was determined as a function of temperature and the amplitude of the applied stress. The dominant factor of the microstructure change was the stress-induced acceleration of the atomic diffusion of the component elements in the alloy. In order to improve the long-term reliability of the alloy, it is very important to increase the activation energy by modifying the microstructure of this alloy.
Kinematic Analysis and Design of Eccentric Rolling Transmission
Authors: Pabiszczak Stanislaw , Myszkowski Adam , Staniek Roman , Macyszyn Lukasz
Published: January 2018

The paper shows an idea of a new type of mechanical gear — the eccentric rolling transmission. The main parts of that transmission are rolling bearings, mounted eccentrically on the input shaft which cooperate with the special-shaped cam wheels mounted on the output shaft. The number of rolling bearings is equal to the number of cam wheels. On the basis of kinematic analysis equations of the curve which describe a shape of cam wheels were determined for two different cases: in the first one the directions of shafts rotations were opposite, and in the second they were the same. Kinematic analysis of the novel transmission was carried out to determine maximum gear ratio depending on the adopted input parameters. As a result of analyses a design procedure of the eccentric rolling transmission and CAD model were prepared.
The Potential for Thermal Waste Energy Recovery in Industrial Kitchens
Authors: Wemhoff A. P. , Dai T. , Fleischer A. S.
Published: January 2018

Industrial kitchens consume significant amounts of energy, largely in the form of heat production by cooking and cleaning equipment, which requires removal by the facility’s heating, ventilating, and air conditioning (HVAC) system. One potential means to improve the energy efficiency of industrial kitchens lies in the use of waste energy recovery of hot wastewater from an industrial-scale dishwasher. Examination of an on-campus dining facility suggests that waste heat recovery can occur at the facility gas hot water heater (HWH) and the dishwasher electric hot water booster (HWB). This study suggests that waste heat recovery is more financially viable in existing construction at the electric HWB, despite yielding less recovered heat than the gas HWH. A payback period of approximately two years is calculated for the installation of a 146 kW shell-and-tube heat exchanger. The corresponding annual source pollution reduction is approximately 13 kg of SO2, 6.5 kg of NOx, and 6.5 metric tons of CO2. However, new construction projects in similar building configurations could also include HWH heat recovery, resulting in a similar payback period but with more substantial annual source pollution reduction values: 14 kg of SO2, 33 kg of NOx, and 38 metric tons of CO2.
Heat Transfer Enhancement in Annular Shear-Thinning Flows Over a Sudden Pipe Expansion
Authors: Hammad Khaled J.
Published: January 2018

Heat transfer enhancement in suddenly expanding annular pipe flows of a shear-thinning non-Newtonian fluid is studied within the steady laminar flow regime. Conservation of mass, momentum, and energy equations, along with the power-law constitutive model are numerically solved. The impact of inflow inertia, annular-nozzle-diameter-ratio, k, power-law index, n, and Prandtl numbers, is reported for: Re = {50, 100}, k = {0, 0.5, 0.7}; n = {1, 0.8, 0.6}; and Pr = {1, 10, 100}. Heat transfer enhancement downstream of the expansion plane, i.e., Nusselt numbers, Nu, higher than the fully developed value, in the downstream pipe, is observed only for Pr = 10 and 100. Higher Prandtl numbers, power-law index values, and annular diameter ratios, in general, reflect a more dramatic heat transfer augmentation downstream of the expansion plane. Heat transfer augmentation for Pr = 10 and 100, is more dramatic for suddenly expanding annular flows, in comparison with suddenly expanding pipe flow. For a given annular diameter ratio and Reynolds numbers, increasing the Prandtl number from Pr = 10 to Pr = 100, always results in higher peak Nu values, for both Newtonian and shear-thinning non-Newtonian flows.
A Method for Solving Rotational Velocity Fluctuation Problem of a 3-DOF Parallel Tool Head
Authors: Wang Dong , Wu Jun , Wang Liping , Si Hao
Published: January 2018

Velocity stability is one of the most important properties for a parallel tool head during machining process. However, due to the nonlinear kinematic transmission characteristics between the motion in joint space and the motion in task space of a parallel manipulator, there exists obvious rotational velocity fluctuation problem of a parallel tool head which couples two degrees of freedom and one translational degree of freedom (2R1T), and the kinematic performance would be heavily affected by the rotational velocity fluctuation problem. Thus, it is a core issue of how to ensure velocity stability of this type parallel tool heads under general numerical control (NC) system. In this paper, by taking a typical 2R1T parallel tool head as an object of study, a method for solving the rotational velocity fluctuation problem is investigated. First, the nonlinear kinematic characteristics of the 2R1T parallel tool head are analyzed to explain the reason of the rotational velocity fluctuation. Next, a completed optimization method of feed rate is proposed to reduce the rotational velocity fluctuation, and the different displacement increments and velocity mapping abilities of each driving shaft are considered. Finally, a comparison experiment is carried out to validate the effectiveness of the method. The result shows that the rotational velocity fluctuation of the 3-DOF parallel tool head is almost eliminated by setting appropriate feed rate.
Specific Consumption Analysis of Vapor Compression Refrigeration System
Authors: Xueliang Bai , Shaoxiang Zhou
Published: January 2018

In real life applications the latest findings of energy savings are playing important role for optimizing and improving the systems. Vapor compression refrigeration systems are some of the most implemented refrigeration systems and most of the energy consumption in this area depends on this system. The power consumption of VCR systems cannot be obtained or compared only with the COP. In order to alleviate the above challenges, a temperature-entropy diagram of actual compression refrigeration cycle is designed to show the differences between the actual and theoretical refrigeration cycles in this research. Second law of thermodynamics was utilized to analyze the entropic and exergy balance of irreversible factors during the refrigeration process. Then specific consumption analysis model of VCR is proposed and specific consumption of specific refrigeration capacity is studied. The proposed method can obtain the actual specific consumption and distribution of the additional specific consumption. Numerical results have shown that the exergy efficiency of the VCR is lower than the COP due to high entropy generation (irreversible losses) because of electricity consumed by the system. An alternative method is introduced for the evaluation of the energy saving potential in VCR system.
Analytical Prediction of Period-1 Motions in a Time-Delayed, Softening Duffing Oscillator
Authors: Luo Albert C. J. , Xing Siyuan
Published: January 2018

In this paper, symmetric and asymmetric period-1 motions in a periodically forced, time-delayed, softening Duffing oscillator is analytically predicted through a discrete implicit mapping method. Such a method is based on the discretization of the corresponding differential equation. The stability and bifurcations of the symmetric and asymmetric period-1 motions are determined through eigenvalue analysis. Numerical simulation of the period-1 motions in the time-delayed softening Duffing oscillator is presented for verification of the analytical prediction.
Flutter Suppression of Bridge Deck Section Using Controllable Winglets Driven by LQR Control
Authors: Bera K. K. , Chandiramani N. K.
Published: January 2018

Active flutter control of bridge deck section using controllable winglets is studied. Self-excited wind forces acting on deck and winglets are modeled using the Scanlan-Tomko model. Vertical, lateral and torsional degrees of freedom are considered for deck and corresponding eighteen experimental flutter derivatives (FD) are used. Winglets are modeled as flat plates and FDs are obtained from Theodorsen functions. Time domain formulation using Rogers rational function approximation leads to divergence speed much lower than the actual one, which is confirmed by Quasi steady theory. Hence, for control study, the usual trial and error method involving sweeping through speed and frequency is used. Rotations of winglets relative to deck are considered as control input, rather than the driving torque. Full state feedback with LQR control is applied. The state variables are estimated by designing a full order observer system using pole placement technique. Winglet rotations being restricted within bounds, the flutter behavior is studied using closed loop responses and compared with eigenvalue analysis. Numerical results shows the implemented control strategy is quite effective in flutter suppression and enhancing the flutter speed.
Fatigue Study on the Right Circular Flexure Hinges for Designing Compliant Mechanisms
Authors: Zhu Benliang , Lu Yihua , Liu Min , Li Hai , Zhang Xianmin
Published: January 2018

Being monolithic with its connected links, the flexure hinge has been widely used for precision engineering where high accuracy is demanded because it has zero friction and backlash. In real application, the flexure hinge is often subjected to periodic loadings, which make it a necessity for its fatigue analysis. In this study, we discussed the fatigue properties of the right circular flexure hinge (RCH). The accurate estimation of the maximum stress in RCH under a certain load is firstly derived. After that, the Stress-Life (S-N) curve was derived from the results of fatigue tests. The design S-N curve (lower-bound S-N curve) was calculated by using the one-sided tolerance limit that derived based on the approximate Owen tolerance limit method. Finally, the effects of the hinge parameters, e.g., the radius r and the thickness t, on the fatigue performance of the RCH were discussed.
Repurposing of a Hybrid Vehicle Nickel Metal Hydride Battery Pack for Electrical Grid Storage
Authors: Balderston Dayton , Kelley John Eric , Crowder James , DeAgostino Thomas , Depcik Christopher
Published: January 2018

Climate change concerns are driving incentives to increase the fuel economy of passenger vehicles. Consequently, this has resulted in a growing prevalence of electrified vehicles (EVs) consisting of hybrid, plug-in hybrid, and fully electric vehicles. Unfortunately, EVs are often removed from the road when 70 to 80% of the original energy capacity remains in their battery pack. In order to maintain or increase the value of EV battery packs in an end-of-vehicle life scenario, there are three potential solutions: remanufacturing for re-use, recycling, or repurposing. However, the complexity of handling dissimilar battery chemistries makes both remanufacturing and recycling a significant challenge. Hence, repurposing may prove to be a more viable short-term goal of the industry.

In order to explore this potential outcome, a team of undergraduate students studied the continuous cycling effects of used and refurbished Toyota® Prius nickel metal hydride battery packs. A Raspberry Pi 2 Model B microcomputer recorded relevant data, including battery pack voltage, energy input, and energy output. In combination, a Laboratory Virtual Instrument Engineering Workbench (LabVIEW™) control system used this logged information to regulate charging and discharging of the battery pack. In addition, to enhance the environmental sustainability of the project, this control system acquired solar information from a nearby weather station, subsequently ensuring that the battery pack only recharged during times of peak solar radiation. Analysis of the pack’s energy balance helped to characterize the cycle life of the pack and its potential in repurposing. Others can emulate the methodology employed as a way to instruct students about the potential left in used vehicular battery packs and their possible integration with the electrical grid.
V50 Ballistic Performance of Unidirectional Woven Basalt Fiber Laminated Composites
Authors: David N. V. , Roslan M. J. Jori , Amri M. Qhairul , Ryan I. Joel , Sundram Raja
Published: January 2018

Ballistic fabrics made from high performance fibers such as para-aramid (synthetic) and basalt (natural) fibers, and composites utilizing these fabrics, are among the leading materials for soft body armor systems. Modern military and other law enforcement operations are technology-driven with weapons and ammunition that demand a flexible, damage- and moisture-resistant, and lightweight ballistic fabrics with superior energy absorbing capacity. Basalt fibers, which are extracted from igneous volcanic rocks, are natural fibers with mechanical and thermo-physical properties that are generally comparable or superior to glass and other synthetic fibers at a lower cost. This gives basalt-based composites an edge over contemporary materials for potential application as anti-ballistic body armor. The aim of the present study is to experimentally determine the V50 performance and penetration resistance of unidirectional woven basalt fiber laminated composites with three different combinations of ply orientations [0°, 45° and 90°] at both CW and CCW directions and number of layers namely, B1 (7 layers), B2 (12 layers) and B3 (16 layers). The V50 performance test was conducted in accordance to the MIL-STD-662F standard using the Universal Test Gun (Prototypa UZ-2002). The V50 ballistic velocity is computed based on a minimum of six shots including three complete penetrations (CP) and three partial penetrations. The MIL-STD-662F standard stipulates that the value of ballistic limit protection should be less than 38 m/s for the purpose of computing V50. The V50 value for sample B1, that yielded to CP at 192 m/s and 172 m/s clean through to the witness plate, could not be determined. The V50 for samples B2 and B3 are 117 m/s and 153 m/s, respectively.

The optimum number of layers of the basalt fabric to sustain the reference penetration velocity of 367 m/s corresponding to threat Level II of the NIJ Standard-0101.04 is calculated for each specimen for further study. The tensile properties and Shore-D hardness levels of the three samples are also measured and reported.
Heat Transfer Technology to Convert Plastic Trash to Oil
Authors: Elsharafi Mahmoud , Chancellor Cody , Duckworth Cameron , Tatla Moiz , Denwe Reuben , Lafleur Okan , Mao Zhiqi , Azzouz Mohamed , Wang Sheldon
Published: January 2018

In modern society, plastic waste has become a serious environmental issue. The inability of most hydrocarbon based plastics to naturally decompose quickly causes concern. The material piles up in landfills, waterways, and along the side of the road. One way to combat this issue is the repurposing of the material. Plastic can be converted back into oil (called pyrolysis) and refined to produce fuels. To attempt this, a custom-built steel reactor is to be filled with waste plastic, and will be heated to the plastic’s boiling point in an inert (N2) environment. The resulting vapor will be recondensed in a specially designed heat exchanger, resulting in oil, wax, and gaseous byproducts. The oil and waxes are collected in one container, and the gases are collected in a separate container. The system will require the use of thermocouples and a feedback loop to properly control temperature. The results are expected to show a correlation between plastic type and resulting byproduct composition with Grade 1 plastics producing the most gas. In addition, faster heating rates, larger plastic particle size, and higher temperatures should increase gaseous products. This may aid in the creation of commercial/industrial sized pyrolysis systems.
Viscosity Measurements for Various Mixed Fluids Used to Enhance Oil Recovery
Authors: Elsharafi Mahmoud O. , Chancellor Cody , Kinyua Denzel , Denwe Reuben
Published: January 2018

In mature reservoirs, the goal is to increase oil mobility and decrease water mobility. As a result, oil production will be increased and unwanted water production will be decreased. Surfactant and alkaline are widely used to change the wettability of reservoir rocks from oil wet to water wet. Viscosity measurements are important in finding out the impact viscous fluids on enhanced oil recovery (EOR). This project focuses on the viscosity measurements of various mixed fluids used in oil-fields to enhance oil recovery. Two types of surfactants (A and B) and one type of alkaline were utilized throughout the work. In addition, different types of oil obtained from different areas were implemented. The viscosity of these mixed fluids was measured while observing the implications of using varying surfactant and alkaline concentrations. Lastly, the effect of temperature on fluid viscosity was monitored.
The Effect of Stiffness and Loading Deviations in a Nonlinear Isolator Having Quasi Zero Stiffness and Geometrically Nonlinear Damping
Authors: Donmez Ata , Cigeroglu Ender , Ozgen Gokhan O.
Published: January 2018

Static deflections due to static loadings limit the isolation performance of linear vibration isolation systems. Therefore, quasi-zero stiffness (QZS) mechanisms, i.e. nonlinear isolators with high static and low dynamic stiffness characteristic, are used to decrease the natural frequency of the isolation structure and improve the isolation performance of the system while having the same loading capacity. However, the resulting system is highly nonlinear and unstable solutions may as well occur. Although increasing the amount of linear viscous damping in the system reduces the nonlinearity, it has adverse effect on the isolation region. Geometrically nonlinear damping is effective when the response of the isolation system increases; hence, isolation region is unaffected. Combination of position depended nonlinear damping and QZS mechanism eliminates highly input depended response of QZS mechanism. In this study, a single degree of freedom system with a nonlinear isolator having QZS mechanism and geometrically nonlinear damping is considered. The nonlinear differential equations of motion of the isolation system are converted into a set of nonlinear algebraic equations by using harmonic balance method, which are solved by using Newton’s method with arc-length continuation. Several case studies are performed and the effect of stiffness and loading deviations on the isolation performance is studied.