bluuebunny/crossref_metadata_2025 huggingface dataset:
Damage Identification for Hysteretic Structures Using a Mode Decomposition Method
Authors: Poskus E. , Rodgers G. W. , Zhou C. , Chase J. G.
Published: December 2017

This article investigates structural health monitoring (SHM) of multidegree of freedom (MDOF) structures after major seismic or environmental events. A recently developed hysteresis loop analysis (HLA) SHM technique has performed robustly for single degree of freedom (SDOF) and single mode dominant MDOF structures. However, strong ground motions can trigger higher vibration modes, resulting in irregular hysteresis loops and making this otherwise robust identification difficult. This study presents a new filtering tool, enabling reconstruction of single mode dominant restoring force‐displacement loops which can be readily used for HLA.

The proposed filtering tool is based on a classic modal decomposition using optimized mode shape coefficients. The optimization process is carried out in a modal space and is based on decoupling frequency response spectra of interfering modes. Application of modal decomposition using the optimized mode shape coefficients allows for reconstruction of single‐mode dominant hysteresis loops, which can be effectively identified using HLA. The proposed filtering tool is validated on the reconstruction of hysteresis loops on an experimental bridge pier test structure with notable contributions from at least two modes.

The results show the method eliminates the influence of all higher modes that contain significant energy content and yields the reconstruction of “smooth” single mode dominant hysteresis loops. The resulting SHM analysis on the reconstructed experimental hysteresis loops identified degradation in the elastic stiffness profiles, indicating damage within the structure and matching prior published results based on physical inspection of damage. The overall method presented increases the breadth of potential application of the HLA method and can be readily generalized to a range of MDOF structures.
Zero‐fluoroscopy permanent pacemaker implantation using Ensite NavX system: Clinical viability or fanciful technique?
Authors: Guo Ping , Qiu Jie , Wang Yan , Chen Guangzhi , Proietti Riccardo , Fadhle AL‐Selmi , Zhao Chunxia , Wen Wang Dao
Published: December 2017

Background

Fluoroscopy is the imaging modality routinely used for cardiac device implantation and electrophysiological procedures. Due to the rising concern regarding the harmful effects of radiation exposure to both the patients and operation staffs, novel 3D mapping systems have been developed and implemented in electrophysiological procedure for the navigation of catheters inside the heart chambers. Their applicability in cardiac device implantation has been rarely reported. Our aim is to evaluate the feasibility and safety of permanent pacemaker implantation without fluoroscopy.

Methods and results

From January 2012 to June 2016, six patients (50 ± 15 years, four of six were female, one of who was at the 25th week of gestation) who underwent permanent pacemaker implantation were included (zero‐fluoroscopy group). Data from 20 consecutive cases of implantation performed under fluoroscopy guidance were chosen as a control group (fluoroscopy group). Total implantation procedure time for single‐chamber pacemaker was 51.3 ± 13.1 minutes in the zero‐fluoroscopy group and 42.6 ± 7.4 minutes in the fluoroscopy group (P  =  0.155). The implantation procedural time for a dual‐chamber pacemaker was 88.3 ± 19.6 minutes and 67.3 ± 7.6 minutes in the zero‐fluoroscopy and fluoroscopy groups (P  =  0.013), respectively. No complications were observed during the procedure and the follow‐up in the two groups, and all pacemakers worked with satisfactory parameters.

Conclusion

Ensite NavX system can be used as a reliable and safe zero‐fluoroscopy approach for the implantation of single‐ or dual‐chamber permanent pacemakers in specific patients, such as pregnant women or in extreme situations when the x‐ray machine is not available.
New generation cardioverter‐defibrillator lead with a floating atrial sensing dipole: Long‐term performance
Authors: Safak Erdal , D´Ancona Giuseppe , Kaplan Hilmi , Caglayan Evren , Kische Stephan , Öner Alper , Ince Hüseyin , Ortak Jasmin
Published: December 2017

Objectives

The study aim is to present the long‐term performance of a new generation implantable cardioverter defibrillator (ICD) electrode with floating atrial dipole (Linox S DX, Biotronik, Berlin, Germany).

Background

The single ICD electrode with a floating dipole in the atrial chamber was introduced about 15 years ago to overcome risk of inappropriate shock.

Methods

After implantation, internal electrocardiogram data were prospectively collected via telemonitoring (Home Monitoring, Biotronik).

Results

A total of 93 patients (81.5% male, 18.5% female; 58.9 ± 12.3 years) were implanted with a single–chamber ICD using the Linox S DX. Patients were followed up for a median of 693 days (33–2,460 days). At time of implantation average p‐wave value was 3.5 ± 1.7 mV and remained stable throughout follow‐up with an average value of 3.7 ± 1 mV (P = 0.2). A total of 460 arrhythmic episodes were recorded and 185 (40.2%) were incorrectly stratified by the device software. Seven patients (7.5%) experienced inappropriate ICD therapy. In three patients, VT episodes were not detected and remained untreated.

Conclusions

Although the Linox S DX lead presents a satisfactory long‐term stability of the atrial sensing, many of the messages sent to the device during follow‐up were incorrectly classified by the ICD software. As a result, inappropriate therapy occurred with a rate similar to that observed with dual‐chamber ICDs, but some malignant arrhythmias remained undiagnosed and untreated while occurring.

Results in larger prospective cohorts should be analyzed and software improvements of the device should be suggested to overcome these potential drawbacks.
Adenosine‐sensitive Wolff‐Parkinson‐White: Longer time across the atrioventricular groove
Authors: Beach Cheyenne , Follansbee Christopher W. , Beerman Lee , Mazzocco Sharon , Wang Li , Arora Gaurav
Published: December 2017

Background

Successful ablation sites in Wolff‐Parkinson‐White syndrome (WPW) are characterized by short atrioventricular (AV) intervals. Approximately 15% of patients with WPW have adenosine‐sensitive accessory pathways (APs). We sought to determine if local AV intervals of adenosine‐sensitive APs are different from those of adenosine‐insensitive APs in patients with WPW.

Methods

Patients ≤21 years with WPW and adenosine‐sensitive APs who underwent successful ablation over a 9‐year period were included. Patients with WPW and adenosine‐insensitive APs were matched by age and weight in a 1:2 case‐control design. AP location, antegrade and retrograde conduction properties, supraventricular tachycardia (SVT) inducibility, local AV interval, interval from delta wave onset to local ventricular activation (del‐V), and time to loss of preexcitation were reviewed.

Results

Fourteen patients with adenosine‐sensitive APs and 28 with adenosine‐insensitive APs were included. Patients with adenosine‐sensitive APs had minimum 1:1 antegrade AP conduction at a longer median paced cycle length (380, interquartile range [IQR] 295 to 585 ms vs 290, IQR 250 to 330 ms, P = 0.046), were less likely to have inducible SVT (35.7% vs 75.0%, P = 0.035), and had a longer median local AV interval (40.5, IQR 30.8 to 58.3 ms vs 32.0, IQR 29.3 to 37.8 ms, P = 0.029) when compared to those with adenosine‐insensitive APs.

Conclusion

Patients with WPW and adenosine‐sensitive APs have 1:1 antegrade AP conduction at longer cycle lengths, lower likelihood of SVT induction, and longer local AV intervals when compared to those with adenosine‐insensitive APs. In patients with WPW, it may be important to consider adenosine response when selecting appropriate ablation targets.
A‐Fibers Mediate Cold Hyperalgesia in Patients with Oxaliplatin‐Induced Neuropathy
Authors: Forstenpointner Julia , Oberlojer Violetta C. , Naleschinski Dennis , Höper Johanna , Helfert Stephanie M. , Binder Andreas , Gierthmühlen Janne , Baron Ralf
Published: December 2017

Cold hyperalgesia is a common side effect of oxaliplatin treatment; still, the pathophysiological and molecular mechanisms as well as the contribution of different primary afferent fiber systems are unclear. Therefore, patients with oxaliplatin‐induced acute neuropathy with (n = 6) and without (n = 7) cold hyperalgesia were tested by applying a preferential blockade of peripheral myelinated A‐fiber afferents in combination with quantitative sensory testing. Additionally, an interview‐based questionnaire assessed the severity of symptoms and the impact on daily activities.

Results indicate a deficit of cold perception in patients without cold hyperalgesia compared to patients with cold hyperalgesia prior to A‐fiber blockade. In patients with cold hyperalgesia, a preferential blockade of A‐fibers abolished cold hyperalgesia.

This suggests that oxaliplatin‐induced cold hyperalgesia is mediated by A‐fibers and that a deficit in A‐fiber function might prevent the development of cold hyperalgesia. The work supports findings in rodents and in human sural nerve biopsies indicating that oxaliplatin interferes with axonal ion conductance in intact A‐fibers by sensitizing potassium and/or sodium channels.

Drugs that act on these molecular targets might be of potential value to treat oxaliplatin‐induced cold hyperalgesia.
Convergent Validity of the Dutch Central Sensitization Inventory: Associations with Psychophysical Pain Measures, Quality of Life, Disability, and Pain Cognitions in Patients with Chronic Spinal Pain
Authors: Kregel Jeroen , Schumacher Charline , Dolphens Mieke , Malfliet Anneleen , Goubert Dorien , Lenoir Dorine , Cagnie Barbara , Meeus Mira , Coppieters Iris
Published: December 2017

Objective

Symptoms of central sensitization (CS) have been described in patients with chronic spinal pain (CSP). Although a gold standard to diagnose CS is lacking, psychophysical pain measures are often used. The Central Sensitization Inventory (CSI) is proposed as an alternative method and indirect tool for the evaluation of CS symptomatology. The aim of the current study was to evaluate the convergent validity of the CSI by investigating the association with psychophysical pain measures and self‐reported measures of current pain intensity, quality of life, disability, and catastrophizing in CSP patients.

Methods

One hundred sixteen patients with nonspecific CSP were included in the present study. Patients completed the CSI, were subjected to pressure pain thresholds (PPTs) and a conditioned pain modulation (CPM) paradigm, and completed questionnaires for current pain intensity, quality of life, pain disability, and pain catastrophizing.

Results

Higher CSI scores were weakly correlated with lower PPTs (−0.276 ≤ r ≤ −0.237; all P ≤ 0.01) and not with CPM efficacy (r = 0.017; P = 0.858). Higher CSI scores were moderately correlated with higher current pain intensity (r = 0.320; P < 0.001), strongly correlated with lower physical (r = −0.617; P < 0.001) and emotional (r = −0.635; P < 0.001) quality of life, and moderately correlated with higher pain disability (r = 0.472; P < 0.001) and higher pain catastrophizing (r = 0.464; P < 0.001).

Conclusion

The CSI was weakly associated with PPTs and not with CPM efficacy in CSP patients. Moderate to strong associations were found with current pain intensity, quality of life, disability, and catastrophizing. The current results illustrate that the CSI does not reflect a direct measure of CS, yet is a representation of general distress, possible originating from CS symptoms.
Differential coordination of stomatal conductance, mesophyll conductance, and leaf hydraulic conductance in response to changing light across species
Authors: Xiong Dongliang , Douthe Cyril , Flexas Jaume
Published: December 2017

Stomatal conductance (gs) and mesophyll conductance (gm) represent major constraints to photosynthetic rate (A), and these traits are expected to coordinate with leaf hydraulic conductance (Kleaf) across species, under both steady‐state and dynamic conditions. However, empirical information about their coordination is scarce. In this study, Kleaf, gas exchange, stomatal kinetics, and leaf anatomy in 10 species including ferns, gymnosperms, and angiosperms were investigated to elucidate the correlation of H2O and CO2 diffusion inside leaves under varying light conditions. Gas exchange, Kleaf, and anatomical traits varied widely across species. Under light‐saturated conditions, the A, gs, gm, and Kleaf were strongly correlated across species. However, the response patterns of A, gs, gm, and Kleaf to varying light intensities were highly species dependent. Moreover, stomatal opening upon light exposure of dark‐adapted leaves in the studied ferns and gymnosperms was generally faster than in the angiosperms; however, stomatal closing in light‐adapted leaves after darkening was faster in angiosperms. The present results show that there is a large variability in the coordination of leaf hydraulic and gas exchange parameters across terrestrial plant species, as well as in their responses to changing light.
Haem oxygenase: A functionally diverse enzyme of photosynthetic organisms and its role in phytochrome chromophore biosynthesis, cellular signalling and defence mechanisms
Authors: Mahawar Lovely , Shekhawat Gyan Singh
Published: December 2017

Haem oxygenase (HO) is a universal enzyme that catalyses stereospecific cleavage of haem to BV IX α and liberates Fe+2ion and CO as by‐product. Beside haem degradation, it has important functions in plants that include cellular defence, stomatal regulation, iron mobilization, phytochrome chromophore synthesis, and lateral root formation. Phytochromes are an extended family of photoreceptors with a molecular mass of 250 kDa and occur as a dimer made up of 2 equivalent subunits of 125 kDa each. Each subunit is made of two components: the chromophore, a light‐capturing pigment molecule and the apoprotein. Biosynthesis of phytochrome (phy) chromophore includes the oxidative splitting of haem to biliverdin IX by an enzyme HO, which is the decisive step in the biosynthesis. In photosynthetic organisms, BVα is reduced to 3Z PΦB by a ferredoxin‐dependent PΦB synthase that finally isomerised to PΦB. The synthesized PΦB assembles with the phytochrome apoprotein in the cytoplasm to generate holophytochrome. Thus, necessary for photomorphogenesis in plants, which has confirmed from the genetic studies, conducted onArabidopsis thalianaand pea. Besides the phytochrome chromophore synthesis, the review also emphasises on the current advances conducted in plant HO implying its developmental and defensive role.
Seasonality of cavitation and frost fatigue in Acer mono Maxim.
Authors: Zhang Wen , Feng Feng , Tyree Melvin T.
Published: December 2017

Although cavitation is common in plants, it is unknown whether the cavitation resistance of xylem is seasonally constant or variable. We tested the changes in cavitation resistance of Acer mono before and after a controlled cavitation–refilling and freeze–thaw cycles for a whole year. Cavitation resistance was determined from ‘vulnerability curves’ showing the percent loss of conductivity versus xylem tension. Cavitation fatigue was defined as a reduction of cavitation resistance following a cavitation–refilling cycle, whereas frost fatigue was caused by a freeze–thaw cycle. A. mono developed seasonal changes in native embolisms; values were relatively high during winter but relatively low and constant throughout the growing season. Cavitation fatigue occurred and changed seasonally during the 12‐month cycle; the greatest fatigue response occurred during summer and the weakest during winter, and the transitions occurred during spring and autumn. A. mono was highly resistant to frost damage during the relatively mild winter months; however, a quite different situation occurred during the growing season, as the seasonal trend of frost fatigue was strikingly similar to that of cavitation fatigue. Seasonality changes in cavitation resistance may be caused by seasonal changes in the mechanical properties of the pit membranes.
Outcome of antibody‐mediated rejection compared to acute cellular rejection after pediatric heart transplantation
Authors: Vaughn Gabrielle R. , Jorgensen Neal W. , Law Yuk M. , Albers Erin L. , Hong Borah J. , Friedland‐Little Joshua M. , Kemna Mariska S.
Published: December 2017

Outcomes of ACR after pediatric HTx have been well described, but less has been reported on outcomes of AMR. We compared the clinical characteristics and cardiovascular outcomes (composite end‐point of death, retransplantation, or allograft vasculopathy) of pediatric HTx recipients with AMR, ACR, and no rejection in a retrospective single‐center study of 104 recipients. Twenty were treated for AMR; 15 were treated for ACR. Recipients with AMR had an increased frequency of congenital heart disease (90% vs ACR 67% vs no rejection 59%, P = .03), homograft (68% vs 7% vs 18%, P < .001), HLA sensitization (45% vs 13% vs 13%, P = .008), and positive cross‐match (30% vs 7% vs 9%, P = .046). AMR caused hemodynamic compromise more often than ACR (39% vs 4%, P = .02). AMR recipients had worse cardiovascular outcome than recipients with ACR or no rejection (40% vs 20% vs 8.6%, P = .003). In bivariate Cox analysis, AMR (HR 4.1, CI 1.4‐12.0, P = .009) and ischemic time (HR 1.6, CI 1.1‐2.3, P = .02) were associated with worse cardiovascular outcome; ACR was not. In summary, pediatric HTx recipients who develop AMR have worse cardiovascular outcome than recipients who develop only ACR or experience no rejection at all.
Photodynamic therapy in the treatment of symptomatic oral lichen planus: A systematic review
Authors: Akram Zohaib , Javed Fawad , Hosein Mervyn , Al‐Qahtani Mohammed A. , Alshehri Fayez , Alzahrani Ahmed I. , Vohra Fahim
Published: December 2017

Background

The aim of this systematic review was to assess the efficacy of photodynamic therapy (PDT) in the treatment of symptomatic oral lichen planus (OLP).

Methods

This systematic review aimed to address the following focused question: “Is PDT effective in the treatment of symptomatic OLP?” Indexed databases such as MEDLINE, EMBASE, and CENTRAL were searched up to and including August 2017.

Results

Six clinical studies were included. The risk of bias was considered high in 5 studies and moderate in one study. Parameters of PDT such as wavelengths, energy fluence, power density and exposure time ranged between 320‐660 nm, 120 J/cm2, 130 mW/cm2, and 70‐150 seconds, respectively. The follow‐up period ranged from 4 to 48 weeks. All included studies reporting clinical scores showed that PDT was effective in the treatment of OLP in adult patients at follow‐up. However, PDT did not show significant improvement when compared with steroid therapy.

Conclusion

Photodynamic therapy appears to have some effect in the symptomatic treatment of OLP in adult patients. However, further randomized controlled trials with long follow‐up period, standardized PDT parameters, and comparing the efficacy of PDT with steroid therapy are warranted to obtain strong conclusions in this regard.
Spheroid‐type of AL amyloid deposition associated with colonic adenocarcinoma: A case report with literature review
Authors: Kim Moon Joo , McCroskey Zulfia , Piao Yingchao , Belcheva Anna , Truong Luan , Kurtin Paul J. , Ro Jae Y.
Published: December 2017

We report a colonic adenocarcinoma associated with diffuse submucosal deposition of a peculiar spheroid‐type amyloid identified in the colon, terminal ileum, and appendix. A 65‐year‐old woman with past medical histories of hypertension, and chronic obstructive pulmonary disease, presented to the emergency room with cramping abdominal pain and nausea. A computed tomography (CT) scan of abdomen showed right colonic volvulus. Emergency right hemicolectomy was performed. The specimen showed colonic adenocarcinoma with focal submucosal invasion (pT1) arising from a villotubular adenoma. A diffuse submucosal spheroid‐type amyloid deposition (resembling corpora amylacea‐like structures with Liesegang ring formation) was identified in the colon, ileum, and appendix. Electron microscopy examination of this unusual spheroidal‐type material further confirmed the presence of amyloid fibrils. Analysis by liquid chromatography–mass spectrometry detected AL (lambda) type amyloidosis in this specimen. Tests for monoclonal gammopathy were not performed because patient consent was not obtained. In tissue section evaluation, however, no plasma cell neoplasm was identified. Cases with isolated AL amyloid deposition in the gastrointestinal tract have been reported rarely, and there is no case report of colonic adenocarcinoma associated with primary amyloid deposition in the English literature.
Diaheliotropic leaf movement enhances leaf photosynthetic capacity and photosynthetic light and nitrogen use efficiency via optimising nitrogen partitioning among photosynthetic components in cotton (Gossypium hirsutum L.)
Authors: Yao H. , Zhang Y. , Yi X. , Zhang X. , Fan D. , Chow W. S. , Zhang W.
Published: December 2017

Phototropic leaf movement of plants is an effective mechanism for adapting to light conditions. Light is the major driver of plant photosynthesis. Leaf N is also an important limiting factor on leaf photosynthetic potential. Cotton (Gossypium hirsutum L.) exhibits diaheliotropic leaf movement. Here, we compared the long‐term photosynthetic acclimation of fixed leaves (restrained) and free leaves (allowed free movement) in cotton.

The fixed leaves and free leaves were used for determination of PAR, leaf chlorophyll concentration, leaf N content and leaf gas exchange. The measurements were conducted under clear sky conditions at 0, 7, 15 and 30 days after treatment (DAT).

The results showed that leaf N allocation and partitioning among different components of the photosynthetic apparatus were significantly affected by diaheliotropic leaf movement. Diaheliotropic leaf movement significantly increased light interception per unit leaf area, which in turn affected leaf mass per area (LMA), leaf N content (NA) and leaf N allocation to photosynthesis (NP). In addition, cotton leaves optimised leaf N allocation to the photosynthetic apparatus by adjusting leaf mass per area and NA in response to optimal light interception.

In the presence of diaheliotropic leaf movement, cotton leaves optimised their structural tissue and photosynthetic characteristics, such as LMA, NA and leaf N allocation to photosynthesis, so that leaf photosynthetic capacity was maximised to improve the photosynthetic use efficiency of light and N under high light conditions.
Large‐scale screening and characterisation of Lemna aequinoctialis and Spirodela polyrhiza strains for starch production
Authors: Ma Y. B. , Zhu M. , Yu C. J. , Wang Y. , Liu Y. , Li M. L. , Sun Y. D. , Zhao J. S. , Zhou G. K.
Published: December 2017

Duckweed is considered a promising feedstock for bioethanol production due to its high biomass and starch production. Selection of duckweed strains with high starch accumulation is essential for application of duckweeds to bioethanol production. Geographic differentiation had a large influence on genetic diversity of duckweeds.

Biomass production, starch content and starch amount in geographically isolated strains of 20 Lemna aequinoctialis and Spirodela polyrhiza were calculated to evaluate their potential for bioethanol production. The influence of different collection time, culture medium and NaCl concentration on starch accumulation of the best strains were analysed.

The results showed that biomass production, starch content and starch production of duckweeds demonstrated clonal dependency. The best strain was L. aequinoctialis 6000, with biomass production of 15.38 ± 1.47 g m−2, starch content of 28.68 ± 1.10% and starch production of 4.39 ± 0.25 g m−2. Furthermore, starch content of L. aequinoctialis 6000 was highest after 8 h of light, tap water was the best medium for starch induction, and NaCl did not induce starch accumulation.

This study suggests duckweed biomass production and starch production demonstrate clonal dependency, indicating that extensive clonal comparisons will be required to identify the most suitable isolates for duckweed selective breeding for bioethanol.
Force coordination strategies in on‐water single sculling: Are asymmetries related to better rowing performance?
Authors: Warmenhoven J. , Smith R. , Draper C. , Harrison A. J. , Bargary N. , Cobley S.
Published: December 2017

Asymmetries of the rowing stroke cycle have been assessed with reference to kinematics and foot‐force measures in laboratory testing environments. It remains unclear how asymmetries in propulsive kinetic measures are related to on‐water rowing performance. A new approach for the evaluation of both global and local asymmetries across the entire movement was used to assess the continuous role of asymmetries and whether these change according to the level of competitive representation. Twenty‐seven highly skilled female rowers (national and international competition level), rowing at 32 strokes per minute in a single scull boat, were evaluated. A symmetry index (SI) and functional data analysis (FDA) techniques were applied to a continuous difference time‐series, which described fluctuating asymmetry in propulsive pin forces for each rower. Univariate ANOVAs revealed that differences in asymmetries were present as a factor of competition level for the SI and results of FDA. International athletes were more likely to utilize an asymmetry strategy with increased stroke‐side (port‐side) force early in the drive phase and increased bow‐side (starboard) force through the second half of the drive. This was likely the result of international performers customizing their movement strategies relative to known boat mechanical offsets. The first half of the drive phase was also found to be an adaptive part of the rowing stroke cycle, suggesting asymmetries may have a functional role in successful execution of movements during the rowing stroke.
An Experimental Investigation on the Combustion Process of a Simulated Turbocharged Spark Ignition Natural Gas Engine Operated on Stoichiometric Mixture
Authors: Li Hailin , Gatts Timothy , Liu Shiyu , Wayne Scott , Clark Nigel , Mather Daniel
Published: December 2017

This research investigated the combustion process of an AVL Model LEF/Volvo 5312 single cylinder engine configured to simulate the operation of a heavy-duty spark ignition (SI) natural gas (NG) engine operated on stoichiometric mixture. The factors affecting the combustion process that were examined include intake pressure, spark timing (ST), and the addition of diluents including nitrogen (N2) and carbon dioxide (CO2) to the NG to simulate low British thermal unit (BTU) gases. The mixing of diluents with NG is able to slow down the flame propagation speed, suppress the onset of knock, and allow the engine to operate on higher boost pressure for higher power output. The addition of CO2 was more effective than N2 in suppressing the onset of knock and slowing down the flame propagation speed due to its high heat capacity. Boosting intake pressure significantly increased the heat release rate (HRR) evaluated on J/°CA basis which represents the rate of mass of fuel burning. However, its impact on the normalized HRR evaluated on %/°CA basis, representing the flame propagation rate, was relatively mild. Boosting the intake pressure from 1.0 to 1.8 bar without adding diluents increased the peak HRR to 1.96 times of that observed at 1.0 bar. The increase was due to the burning of more fuel (about 1.8 times), and the 12.9% increase in the normalized HRR. The latter was due to the shortened combustion duration from 23.6 to 18.2 °CA, a 22.9% reduction. The presence of 40% CO2 or N2 in their mixture with NG increased the peak cylinder pressure (PCP) limited brake mean effective pressure (BMEP) from 17.2 to about 20.2 bar. The combustion process of a turbocharged SI NG engine can be approximated by referring to the HRR measured under a naturally aspirated condition. This makes it convenient for researchers to numerically simulate the combustion process and the onset of knock of turbocharged SI NG engines using combustion process data measured under naturally aspirated conditions as a reference.
Fluid Mechanics of Liquid Metal Batteries
Authors: Kelley Douglas H. , Weier Tom
Published: December 2017

The design and performance of liquid metal batteries (LMBs), a new technology for grid-scale energy storage, depend on fluid mechanics because the battery electrodes and electrolytes are entirely liquid. Here, we review prior and current research on the fluid mechanics of LMBs, pointing out opportunities for future studies. Because the technology in its present form is just a few years old, only a small number of publications have so far considered LMBs specifically. We hope to encourage collaboration and conversation by referencing as many of those publications as possible here. Much can also be learned by linking to extensive prior literature considering phenomena observed or expected in LMBs, including thermal convection, magnetoconvection, Marangoni flow, interface instabilities, the Tayler instability, and electro-vortex flow. We focus on phenomena, materials, length scales, and current densities relevant to the LMB designs currently being commercialized. We try to point out breakthroughs that could lead to design improvements or make new mechanisms important.
Biomechanics and Mechanobiology of Saphenous Vein Grafts
Authors: Gooch Keith J. , Firstenberg Michael S. , Shrefler Brittany S. , Scandling Benjamin W.
Published: December 2017

Within several weeks of use as coronary artery bypass grafts (CABG), saphenous veins (SV) exhibit significant intimal hyperplasia (IH). IH predisposes vessels to thrombosis and atherosclerosis, the two major modes of vein graft failure. The fact that SV do not develop significant IH in their native venous environment coupled with the rapidity with which they develop IH following grafting into the arterial circulation suggests that factors associated with the isolation and preparation of SV and/or differences between the venous and arterial environments contribute to disease progression. There is strong evidence suggesting that mechanical trauma associated with traditional techniques of SV preparation can significantly damage the vessel and might potentially reduce graft patency though modern surgical techniques reduces these injuries. In contrast, it seems possible that modern surgical technique, specifically endoscopic vein harvest, might introduce other mechanical trauma that could subtly injure the vein and perhaps contribute to the reduced patency observed in veins harvested using endoscopic techniques. Aspects of the arterial mechanical environment influence remodeling of SV grafted into the arterial circulation. Increased pressure likely leads to thickening of the medial wall but its role in IH is less clear. Changes in fluid flow, including increased average wall shear stress, may reduce IH while disturbed flow likely increase IH. Nonmechanical stimuli, such as exposure to arterial levels of oxygen, may also have a significant but not widely recognized role in IH. Several potentially promising approaches to alter the mechanical environment to improve graft patency are including extravascular supports or altered graft geometries are covered.
A Comparative Study of Artificial Intelligence Based Models to Predict Performance and Emission Characteristics of a Single Cylinder Diesel Engine Fueled With Diesosenol
Authors: Bhowmik Subrata , Panua Rajsekhar , Kumar Ghosh Subrata , Debroy Durbadal , Paul Abhishek
Published: December 2017

This study investigates the potential of oxygenated additive (ethanol) on adulterated diesel fuel on the performance and exhaust emission characteristics of a single cylinder diesel engine. Based on the engine experimental data, two artificial intelligence (AI) models, viz., artificial neural network (ANN) and adaptive-neuro fuzzy inference system (ANFIS), have been modeled for predicting brake thermal efficiency (Bth), brake specific energy consumption (BSEC), oxides of nitrogen (NOx), unburnt hydrocarbon (UBHC) and carbon monoxide (CO) with engine load (%), kerosene (vol %), and ethanol (vol %) as input parameters. Both the proposed AI models have the capacity for predicting input–output paradigms of diesel–kerosene–ethanol (diesosenol) blends with high accuracy. A (3–9–5) topology with Levenberg–Marquardt feed forward back propagation (trainlm) learning algorithm has been observed to be the ideal model for ANN. The comparative study of the two AI models demonstrated that ANFIS predicted results have higher accuracy than the ANN with a maximum RANFIS/RANN value of 1.000534.
Primary Blast Brain Injury Mechanisms: Current Knowledge, Limitations, and Future Directions
Authors: Fievisohn Elizabeth , Bailey Zachary , Guettler Allison , VandeVord Pamela
Published: December 2017

Mild blast traumatic brain injury (bTBI) accounts for the majority of brain injury in United States service members and other military personnel worldwide. The mechanisms of primary blast brain injury continue to be disputed with little evidence to support one or a combination of theories. The main hypotheses addressed in this review are blast wave transmission through the skull orifices, direct cranial transmission, skull flexure dynamics, thoracic surge, acceleration, and cavitation. Each possible mechanism is discussed using available literature with the goal of focusing research efforts to address the limitations and challenges that exist in blast injury research. Multiple mechanisms may contribute to the pathology of bTBI and could be dependent on magnitudes and orientation to blast exposure. Further focused biomechanical investigation with cadaver, in vivo, and finite element models would advance our knowledge of bTBI mechanisms. In addition, this understanding could guide future research and contribute to the greater goal of developing relevant injury criteria and mandates to protect our soldiers on the battlefield.
Spreading Resistance in Multilayered Orthotropic Flux Channels With Different Conductivities in the Three Spatial Directions
Authors: Al-Khamaiseh Belal , Muzychka Yuri S. , Kocabiyik Serpil
Published: December 2017

In the microelectronics industry, the multilayered structures are found extensively where the microelectronic device/system is manufactured as a compound system of different materials. Recently, a variety of new materials have emerged in the microelectronics industry with properties superior to Silicon, enabling new devices with extreme performance. Such materials include β-Gallium-oxide (β-Ga2O3), and black phosphorus (BP), which are acknowledged to have anisotropic thermal conductivity tensors. In many of these devices, thermal issues due to self-heating are a problem that affects the performance, efficiency, and reliability of the devices. Analytical solutions to the heat conduction equation in such devices with anisotropic thermal conductivity tensor offer significant computational savings over numerical methods. In this paper, general analytical solutions for the temperature distribution and the thermal resistance of a multilayered orthotropic system are obtained. The system is considered as a multilayered three-dimensional (3D) flux channel consisting of N-layers with different thermal conductivities in the three spatial directions in each layer. A single eccentric heat source is considered in the source plane while a uniform heat transfer coefficient is considered along the sink plane. The solutions account for the effect of interfacial conductance between the layers and for considering multiple eccentric heat sources in the source plane. For validation purposes, the analytical results are compared with numerical solution results obtained by solving the problem with the finite element method (FEM) using the ANSYS commercial software package.
On the Steady-State Temperature Rise During Laser Heating of Multilayer Thin Films in Optical Pump–Probe Techniques
Authors: Braun Jeffrey L. , Szwejkowski Chester J. , Giri Ashutosh , Hopkins Patrick E.
Published: December 2017

In this study, we calculate the steady-state temperature rise that results from laser heating of multilayer thin films using the heat diffusion equation. For time- and frequency-domain thermoreflectance (TDTR and FDTR) that rely on modulated laser sources, we decouple the modulated and steady-state temperature profiles to understand the conditions needed to achieve a single temperature approximation throughout the experimental volume, allowing for the estimation of spatially invariant thermal parameters within this volume. We consider low thermal conductivity materials, including amorphous silicon dioxide (a-SiO2), polymers, and disordered C60, to demonstrate that often-used analytical expressions fail to capture this temperature rise under realistic experimental conditions, such as when a thin-film metal transducer is used or when pump and probe spot sizes are significantly different. To validate these findings and demonstrate a practical approach to simultaneously calculate the steady-state temperature and extract thermal parameters in TDTR, we present an iterative algorithm for obtaining the steady-state temperature rise and measure the thermal conductivity and thermal boundary conductance of a-SiO2 with a 65-nm gold thin film transducer. Furthermore, we discuss methods of heat dissipation to include the use of conductive substrates as well as the use of bidirectional heat flow geometries. Finally, we quantify the influence of the optical penetration depth (OPD) on the steady-state temperature rise to reveal that only when the OPD approaches the characteristic length of the temperature decay does it alter the temperature profile relative to the surface heating condition.
Nanocomposite capsules with directional, pulsed nanoparticle release
Authors: Udoh Christiana E. , Cabral João T. , Garbin Valeria
Published: December 2017

Nanocomposite microcapsules with bicontinuous internal morphology release nanoparticles in directional bursts.
Core-binding factor β and Runx transcription factors promote adaptive natural killer cell responses
Authors: Rapp Moritz , Lau Colleen M. , Adams Nicholas M. , Weizman Orr-El , O’Sullivan Timothy E. , Geary Clair D. , Sun Joseph C.
Published: December 2017

Runx1 and Runx3 play nonredundant roles in promoting the clonal expansion of NK cells during viral infection.
Fifteen minute consultation: an approach to the child with chronic headaches
Authors: Aspinall Nichola , D’Urso Anita , Ambegaonkar Gautam
Published: December 2017

Children with chronic headache are a common referral to paediatric outpatients. This article suggests an approach to the assessment and management of chronic headaches, offering practical strategies for management as there is limited literature in paediatrics for this.
Fifteen-minute consultation: an approach to a child presenting to the emergency department with acute psychotic symptoms
Authors: Israni Anil Vasudev , Kumar Sumant , Hussain Nahin
Published: December 2017

Presentation of a child in the A&E with altered behaviour including psychotic features is not unusual. New-onset psychotic symptoms in children pose a significant diagnostic challenge due to several reasons. First, primary psychotic conditions are uncommon in pre-pubertal children. Second, differentiating between delirium and psychosis can be difficult in children, more so in infants, toddlers and young children. Third, intervening and managing a secondary cause of psychosis can significantly optimise outcome. Prompt recognition of a possible underlying cause for a child’s psychotic behaviour is essential, and at the same time challenging, in the emergency department. This article attempts to present a systematic approach to a child with acute onset of psychotic symptoms in an emergency setting.
Perceptions of group exercise courses and instructors among Quebec adults
Authors: Gilbert Monique , Chaubet Philippe , Karelis Antony , Dancause Kelsey Needham
Published: December 2017

Background

Group exercise courses are popular among adults, but dropout rates are high. Studies of relationships between participants’ perceptions and their participation might highlight factors to target to improve adherence and re-enrolment.

Methods

We used a mixed-methods approach to analyse perceptions of group exercise courses and instructors among 463 adults. Participants completed the Exercise Barriers and Benefits Scale, questionnaires on perceptions of the instructor and course, and non-participation. We assessed participation from weeks 2–4 and 5–10, and re-enrolment. We analysed relationships between perceptions and re-enrolment using linear regression and mediation analyses. We conducted group interviews with 11 participants.

Results

Predictors of re-enrolment included early participation (β=0.11, P=0.029) and perceptions of the group social climate (P=0.027). Perceptions of the group mediated the relationship between early participation and re-enrolment (95% CI 0.0036 to 0.0471): early participation predicted more positive perceptions (β=2.11, P=0.003), which predicted re-enrolment (β=0.01, P=0.006). Qualitative analyses highlighted instructors’ roles in promoting social exchange and integrating participants into the group.

Conclusions

The social climate of group exercise courses is a key factor predicting re-enrolment. Early participation predicts re-enrolment on its own, and also promotes positive perceptions of the group. Instructors can target these factors by sensitising participants to the importance of early participation, and promoting social exchange.
Sport and exercise medicine research activity in the Arab world: a 15-year bibliometric analysis
Authors: Fares Mohamad Y , Fares Jawad , Baydoun Hasan , Fares Youssef
Published: December 2017

Background

The role of sports in decreasing the prevalence of many diseases has led to a growing interest in the field of sport and exercise medicine. But sport and exercise medicine still remains new to the Arab world, waiting to be explored. The aim of this study is to describe and characterise sport and exercise medicine research activity in the Arab world between 2002 and 2016.

Methods

The PubMed database was used to search for publications related to sport and exercise medicine. Publications were classified according to the country of origin and filtered to include publications between 2002 and 2016. Research output was analysed with respect to gross domestic product (GDP) and population of each country.

Results

A total of 1148 papers related to sport and exercise medicine were found to be published in the Arab countries between 2002 and 2016. Sport-and-exercise-medicine-related publications constituted 0.86% of the total biomedical research papers published in the Arab world and 0.49% of the world’s sport and exercise medicine literature. The number of sport-and-exercise-medicine-related publications per country ranged from zero to 352, with Qatar occupying the top spot. Tunisia ranked first with respect to publications per average GDP, while Qatar ranked first with respect to publications per average population. Comoros, Mauritania, Somalia, Sudan and Yemen were found to have no publications related to sport and exercise medicine.

Conclusion

Sport and exercise medicine is a novel field in the Arab world. Recognising the barriers facing sport and exercise medicine research and exploring them meticulously remains an essential part of the plan to improve the Arab world’s output and contribution in this field.
Fall-related accidents among hikers in the Austrian Alps: a 9-year retrospective study
Authors: Faulhaber Martin , Pocecco Elena , Niedermeier Martin , Ruedl Gerhard , Walter Dagmar , Sterr Regina , Ebner Hans , Schobersberger Wolfgang , Burtscher Martin
Published: December 2017

Objective

To analyse the circumstances of fatal and non-fatal mountain hiking accidents caused by falls.

Methods

The study was designed as a retrospective analysis. Mountain hiking accidents caused by falls were documented during a 9-year period (2006–2014). After screening of all data for potential exclusion criteria the final sample size of 5368 accidents and 5665 victims was included into the analyses. Main outcome measures were details about accidents, victims, type of trail and surface.

Results

The annual number of accidents showed a continuous increase from 467 in 2006 to 700 in 2014. In total, 5.8% of all victims died during the 9-year period. 75.3% of the hikers fell during descent and 80.9% of the victims had their accident on a marked hiking trail or small path. The sex ratio for non-fatal accidents was 55% female and 45% male; for fatal accidents the female-to-male ratio was 28%:72%. Mean age of all victims was 52.5±17.5 years and victims of fatalities were about 5 years older compared with victims of non-fatal accidents (57.5±16.5 vs 52.2±17.5 years, P<0.01).

Conclusion

Descent is the most risky part for accidents caused by falls during mountain hiking. Male hikers are at greater risk for fatalities independent of age and this is associated with accidents occurring in pathless terrain. The death rate from falls was 6%. We recommend a critical self-assessment of the individual capabilities and mountain hiking skills and adequate planning of the hiking tours for mountain hikers.
Auras and the risk of seizures with impaired consciousness following epilepsy surgery: implications for driving
Authors: Fairclough Sam , O’Keeffe Aidan G , de Tisi Jane , Duncan John S
Published: December 2017

Objective

To calculate the chance of a seizure in the next year (COSY) for seizures with impaired awareness in those experiencing auras only, those with no seizures and those with continuing seizures. Epilepsy surgery is an effective treatment for refractory focal epilepsy. Driving is an important factor affecting quality of life. In the UK, driving is not permitted if focal seizures with no impairment of awareness (auras, simple partial seizures) continue, if there is a prior history of seizures with impaired awareness, as will invariably be the case in those having epilepsy surgery. Current UK driving regulations allow driving if COSY is less than 20%.

Method

We calculated COSY in 819 epilepsy surgery patients with up to 25 years follow-up. Each patient year was graded on the The International League against Epilepsy surgery outcome scale.

Results

Patients who were entirely seizure-free for 1, 2 and 3 years had COSY of 4.9%, 3.5% and 2.4% respectively. Patients with only auras within the last 1, 2 or 3 years had a COSY of 11.3%, 9.2% and 7.8% respectively.

Conclusions

Individuals with auras only after epilepsy surgery had a higher COSY than those who were seizure-free. If a COSY of below 20% is regarded as an acceptable risk, it may be suggested that those with auras only in a given year be allowed to drive. The relative risk of these patients causing accidents is lower than population groups such as those aged <25 or >75 years, who are permitted to drive.