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This paper investigates the aerodynamics of a wing under figure-of-eight flapping motion based on Fluid–Structure Interaction (FSI) Computational Fluid Dynamics (CFD) simulations. The kinematic of a wing under figure-of-eight motion creates a condition with a variable angle-of-attack. The effect of using different angles of attack at an initial condition, namely initial pitch angles, for the wing and the spatial size of the figure-of-eight pattern, namely the input link angle, is investigated. The initial pitch angles input is varied from 0° to 330° in steps of 30°, and the input link angles used are 30°, 45°, and 60°. The Young’s modulus of the wing is 3.4 GPa spanwise, which is the elastic modulus of balsa wood material. In comparison with an initial pitch angle of 0°, the 90° initial pitch angle shows much better flight performance in terms of lift generated and stability. The results show that the maximum average lift coefficient of 0.393 occurs at the 90° initial pitch angle. The maximum lift-induced moment for the 90° initial pitch angle is only 5.55% of the maximum lift induced moment for the 0° initial pitch angle. A higher input link angle generates a greater lift force. The pressure distribution in the vicinity of the wing area and the von Mises stress of the wing are also presented.
Gravitational waves from coalescing neutron stars encode information about nuclear matter at extreme densities, inaccessible by laboratory experiments. The late inspiral is influenced by the presence of tides, which depend on the neutron star equation of state. Neutron star mergers are expected to often produce rapidly rotating remnant neutron stars that emit gravitational waves. These will provide clues to the extremely hot post-merger environment. This signature of nuclear matter in gravitational waves contains most information in the 2–4 kHz frequency band, which is outside of the most sensitive band of current detectors. We present the design concept and science case for a Neutron Star Extreme Matter Observatory (NEMO): a gravitational-wave interferometer optimised to study nuclear physics with merging neutron stars. The concept uses high-circulating laser power, quantum squeezing, and a detector topology specifically designed to achieve the high-frequency sensitivity necessary to probe nuclear matter using gravitational waves. Above 1 kHz, the proposed strain sensitivity is comparable to full third-generation detectors at a fraction of the cost. Such sensitivity changes expected event rates for detection of post-merger remnants from approximately one per few decades with two A+ detectors to a few per year and potentially allow for the first gravitational-wave observations of supernovae, isolated neutron stars, and other exotica.
In this article, Si nanoparticle (NP) films were prepared by pulsed laser ablation (PLA) in the argon atmosphere of 10 Pa at room temperature under different pulse repetition rates from 1 to 40 Hz without the baffle. Different from the conventional PLA method, the substrates were placed below and parallel to the ablated plume axis. The obtained films containing NPs were characterized by scanning electron microscopy and Raman spectrometer. The experimental results under constant laser fluence demonstrate the strong dependence of the mean size and the area number density of NPs on the repetition rate. Specifically, with the increase of pulse repetition rate, the mean size of the NPs in the film first decreases and reaches its minimum at 20 Hz, and then increases after 20 Hz, and decreases again till 40 Hz. The area number density shows the contrary trend versus mean size. The in situ diagnostic results of Langmuir probe denote the ablated Si ion density increases monotonously with the increase of repetition rate, while the temperature is almost constant. Combining with the nucleation probability, the growth/aggregation duration of NPs in the “nucleation region” and the effect of the baffle, the influence of pulse repetition rate on the formation of NPs is addressed. It is found that the repetition rate impacts the growth modes of NPs (i.e., growth and aggregation). 1–20, 20–30, and 30–40 Hz, respectively, correspond to growth-, aggregation-, and growth-controlled rate ranges without the baffle; however, 1–10, 10–20, and 20–40 Hz, respectively, correspond to growth-controlled, aggregation/growth-coexisted, and aggregation-controlled rate ranges with the baffle.
This study aimed to highlight the key studies that have led to the current understanding and treatment of head and neck cancer.
The Thomson Reuters Web of Science database was used to identify relevant manuscripts. The results were ranked according to the number of citations. The 100 most cited papers were analysed.
A total of 63 538 eligible papers were returned. The median number of citations was 626. The most cited paper compared radiotherapy with and without cetuximab (3205 citations). The New England Journal of Medicine had the most citations (23 514), and the USA had the greatest number of publications (n = 66). The most common topics of publication were the treatment (n = 45) and basic science (n = 19) of head and neck cancer, followed by the role of human papillomavirus (n = 16).
This analysis highlighted key articles that influenced head and neck cancer research and treatment. It serves as a guide as to what makes a ‘citable’ paper in this field.
Viral pneumonia is an important cause of death and morbidity among infants worldwide. Transmission of non-influenza respiratory viruses in households can inform preventative interventions and has not been well-characterised in South Asia. From April 2011 to April 2012, household members of pregnant women enrolled in a randomised trial of influenza vaccine in rural Nepal were surveyed weekly for respiratory illness until 180 days after birth. Nasal swabs were tested by polymerase chain reaction for respiratory viruses in symptomatic individuals. A transmission event was defined as a secondary case of the same virus within 14 days of initial infection within a household. From 555 households, 825 initial viral illness episodes occurred, resulting in 79 transmission events. The overall incidence of transmission was 1.14 events per 100 person-weeks. Risk of transmission incidence was associated with an index case age 1–4 years (incidence rate ratio (IRR) 2.35; 95% confidence interval (CI) 1.40–3.96), coinfection as initial infection (IRR 1.94; 95% CI 1.05–3.61) and no electricity in household (IRR 2.70; 95% CI 1.41–5.00). Preventive interventions targeting preschool-age children in households in resource-limited settings may decrease the risk of transmission to vulnerable household members, such as young infants.
Abnormal effort-based decision-making represents a potential mechanism underlying motivational deficits (amotivation) in psychotic disorders. Previous research identified effort allocation impairment in chronic schizophrenia and focused mostly on physical effort modality. No study has investigated cognitive effort allocation in first-episode psychosis (FEP).
Cognitive effort allocation was examined in 40 FEP patients and 44 demographically-matched healthy controls, using Cognitive Effort-Discounting (COGED) paradigm which quantified participants’ willingness to expend cognitive effort in terms of explicit, continuous discounting of monetary rewards based on parametrically-varied cognitive demands (levels N of N-back task). Relationship between reward-discounting and amotivation was investigated. Group differences in reward-magnitude and effort-cost sensitivity, and differential associations of these sensitivity indices with amotivation were explored.
Patients displayed significantly greater reward-discounting than controls. In particular, such discounting was most pronounced in patients with high levels of amotivation even when N-back performance and reward base amount were taken into consideration. Moreover, patients exhibited reduced reward-benefit sensitivity and effort-cost sensitivity relative to controls, and that decreased sensitivity to reward-benefit but not effort-cost was correlated with diminished motivation. Reward-discounting and sensitivity indices were generally unrelated to other symptom dimensions, antipsychotic dose and cognitive deficits.
This study provides the first evidence of cognitive effort-based decision-making impairment in FEP, and indicates that decreased effort expenditure is associated with amotivation. Our findings further suggest that abnormal effort allocation and amotivation might primarily be related to blunted reward valuation. Prospective research is required to clarify the utility of effort-based measures in predicting amotivation and functional outcome in FEP.
Better understanding of interplay among symptoms, cognition and functioning in first-episode psychosis (FEP) is crucial to promoting functional recovery. Network analysis is a promising data-driven approach to elucidating complex interactions among psychopathological variables in psychosis, but has not been applied in FEP.
This study employed network analysis to examine inter-relationships among a wide array of variables encompassing psychopathology, premorbid and onset characteristics, cognition, subjective quality-of-life and psychosocial functioning in 323 adult FEP patients in Hong Kong. Graphical Least Absolute Shrinkage and Selection Operator (LASSO) combined with extended Bayesian information criterion (BIC) model selection was used for network construction. Importance of individual nodes in a generated network was quantified by centrality analyses.
Our results showed that amotivation played the most central role and had the strongest associations with other variables in the network, as indexed by node strength. Amotivation and diminished expression displayed differential relationships with other nodes, supporting the validity of two-factor negative symptom structure. Psychosocial functioning was most strongly connected with amotivation and was weakly linked to several other variables. Within cognitive domain, digit span demonstrated the highest centrality and was connected with most of the other cognitive variables. Exploratory analysis revealed no significant gender differences in network structure and global strength.
Our results suggest the pivotal role of amotivation in psychopathology network of FEP and indicate its critical association with psychosocial functioning. Further research is required to verify the clinical significance of diminished motivation on functional outcome in the early course of psychotic illness.
Quantifying reasonable crop yield gaps and determining potential regions for yield improvement can facilitate regional plant structure adjustment and promote crop production. The current study attempted to evaluate the yield gap in a region at multi-scales through model simulation and farmer investigation. Taking the winter wheat yield gap in the Huang-Huai-Hai farming region (HFR) for the case study, 241 farmers’ fields in four typical high-yield demonstration areas were surveyed to determine the yield limitation index and attainable yield. In addition, the theoretical and realizable yield gap of winter wheat in 386 counties of the HFR was assessed. Results showed that the average field yield of the demonstration plots was 8282 kg/ha, accounting for 0.72 of the potential yield, which represented the highest production in the region. The HFR consists of seven sub-regions designated 2.1–2.7: the largest attainable yield gap existed in the 2.6 sub-region, in the southwest of the HFR, while the smallest was in the 2.2 sub-region, in the northwest of the HFR. With a high irrigated area rate, the yield gap in the 2.2 sub-region could hardly be reduced by increasing irrigation, while a lack of irrigation remained an important limiting factor for narrowing the yield gap in 2.3 sub-region, in the middle of the HFR. Therefore, a multi-scale yield gap evaluation framework integrated with typical field survey and crop model analysis could provide valuable information for narrowing the yield gap.
Piglets are characteristically cold intolerant and thus susceptible to high mortality. However, browning of white adipose tissue (WAT) can induce non-shivering thermogenesis as a potential strategy to facilitate the animal’s response to cold. Whether cold exposure can induce browning of subcutaneous WAT (sWAT) in piglets in a similar manner as it can in humans remains largely unknown. In this study, piglets were exposed to acute cold (4°C, 10 h) or chronic cold exposure (8°C, 15 days), and the genes and proteins of uncoupling protein 1 (UCP1)-dependent and independent thermogenesis, mitochondrial biogenesis, lipogenic and lipolytic processes were analysed. Interestingly, acute cold exposure induced browning of porcine sWAT, smaller adipocytes and the upregulated expression of UCP1, PGC1α, PGC1β, C/EBPβ, Cidea, UCP3, CKMT1 and PM20D1. Conversely, chronic cold exposure impaired the browning process, reduced mitochondrial numbers and the expression of browning markers, including UCP1, PGC1α and PRDM16. The present study demonstrated that acute cold exposure (but not chronic cold exposure) induces porcine sWAT browning. Thus, browning of porcine sWAT could be a novel strategy to balance the body temperature of piglets, and thus could be protective against cold exposure.
TAOS II is a next-generation occultation survey with the goal of measuring the size distribution of the small end of the Kuiper Belt (objects with diameters 0.5–30 km). Such objects have magnitudes r > 30, and are thus undetectable by direct imaging. The project will operate three telescopes at San Pedro Mártir Observatory in Baja California, México. Each telescope will be equipped with a custom-built camera comprised of a focal-plane array of CMOS imagers. The cameras will be capable of reading out image data from 10,000 stars at a cadence of 20 Hz. The telescopes will monitor the same set of stars simultaneously to search for coincident occultation detections, thus minimising the false-positive rate. This talk described the project, and reported on the progress of the development of the survey infrastructure.
OBJECTIVES/SPECIFIC AIMS: The morbidity and mortality in adults with single ventricular hearts who have undergone Fontan palliation is poorly defined. These patients have a high burden of arrhythmia, heart failure, and re-operation. We hypothesized that age and type of Fontan predict occurrence of arrhythmia. METHODS/STUDY POPULATION: In total, 205 patients aged 18 years who had undergone a Fontan procedure were identified. Those with incomplete data were excluded. Demographic, anatomic, pharmacologic, imaging, hemodynamic, and electrophysiologic data were collected. The χ2 and Mann-Whitney U tests were used to test significance defined as p<0.05. RESULTS/ANTICIPATED RESULTS: Of the 205 patients identified, 59 had been lost to follow-up. Of the 146 patients (77, 53% female) actively followed 18 (12%) had died at a median (IQR) age of 27 (21–34.3); in patients alive as of 10/2016 the median age was 26 years (22–34). Fontan types were lateral tunnel (LT) (n=79, 54.1%), extracardiac (EC) (n=32, 22%), right atrial to pulmonary artery (RV-PA) (n=28, 19%), and Fontan with Bjork modification (n=4, 2.7%). Systemic left ventricle (n=96, 66%) was more common than systemic right ventricle (n=43, 30%). Of the 146 patients, 101 (69%) had significant morbidity or mortality: 86 (59%) were diagnosed with arrhythmia, 18 (12%) died, and 11 (8%) underwent heart transplants. Frequent procedures included: Fontan revisions/cryoablation in 28 (19%), electrophysiology studies with ablation in 73 (50%), and pacemakers in 53 (36%). Of the arrhythmia diagnoses, 57 (64%) were atrial tachyarrhythmias. RV-PA Fontan procedures were associated with significantly more atrial arrhythmia than all other Fontan types (70% vs. 30%; p<0.01). There was no statistical difference in occurrence of atrial arrhythmia in adults with LT Versus EC Fontans (p=0.3). While patients who had undergone RV-PA and Bjork Fontans were older with median age 34 years, there was no significant difference in age between LT and EC (median 24.0 and 24.5). DISCUSSION/SIGNIFICANCE OF IMPACT: Adult survivors of the Fontan procedure suffer from significant morbidity and mortality. The single most prevalent morbidity is atrial arrhythmia. We conclude that RV-PA Fontans, now obsolete, have the highest prevalence of arrhythmia and that there is no difference in arrhythmia burden between LT and EC Fontans. Given the high prevalence of morbidity and mortality in this population, it is imperative that they be followed by cardiologists with expertise in congenital heart disease.
Based upon the Shliomis ferromagnetic fluid model and the Stokes microcontinuum theory incorporating with the Christensen stochastic model, a modified Reynolds equation of centrosymmetric squeeze films has been derived in this paper. The Reynolds equation includes the combined effects of non-Newtonian rheology, magnetic fluids with applied magnetic fields, rotational inertia forces, and surface roughness. To guide the use of the derived equation, the squeeze film of rotational rough-surface circular disks lubricated with non-Newtonian magnetic fluids is illustrated. According to the results obtained, the effects of rotation inertia decrease the load capacity and the squeeze film time of smooth circular disks. By the use of non-Newtonian magnetic fluids with applied magnetic fields, the rotational circular disks predict better squeeze film performances. When the influences of circumferential roughness patterns are considered, the non-Newtonian magnetic-fluid lubricated rotational rough disks with applied magnetic fields provide further higher values of the load capacity and the squeeze film time as compared to those of the smooth case.
The increasing demands on renewable energy nowadays caused the development of marine current turbine industry. In order to improve the current design of marine current turbines, studies were conducted to analyse their hydrodynamic performances during operation. Since most of the time marine current turbines operate in arrays, it is important to understand the interactions between the turbines in order to design the optimum turbine farm. OpenFOAM® was used to simulate the turbine interactions of conventional and biomimetic marine current turbines in tandem configuration. The conventional marine current turbines were referred to Pinon et al. (2012) and Mycek et al. (2013) while the biomimetic marine current turbine was adopted from Chu (2016). The numerical simulations were conducted with turbines in different inter-device distances, A/D. The percentage differences of ‘‘efficiency’’, η between the IFREMER-LOMC and the biomimetic turbine case of inter-device distances, A/D = 4, 6, 8 and 10 are 14.3%, 6.4%, 3% and 1.92% respectively. The results show that the power produced by the biomimetic turbines in tandem is comparable with the IFREMER-LOMC turbines when A/D > 4. The biomimetic marine current turbines can be a fair choice due to their potential to have alternative fabrication method of their sheet-like turbine blades.
On the day that two Chinese bullet trains collided just south of Wenzhou en route to their final destination in Fujian Province in July 2011, it just so happened that China's most wanted fugitive – the Fujian-based smuggler Lai Changxing – was also finally extradited back to China from Canada to face charges for one of the nation's biggest smuggling and corruption scandals in the post-Mao era. Once anticipated as the headline-making event of the day, Lai's return to Beijing on the afternoon of July 23 all but disappeared from state media overnight when the tragedy of the Wenzhou crash and its subsequent botched rescue efforts came to dominate news channels and public attention. Although the date 7/23 quickly became synonymous with the disastrous event of Wenzhou's rail collision, Lai's uneventful return nonetheless developed its own spectral life as part of a growing conspiracy theory of fateful coincidences.
Infamous as the “shadow customs chief” in the port city of Xiamen, where he based his operations from 1996 to 1999, Lai at one point had controlled entire local departments of the Fujian Customs, with an estimated 160 customs staff, including Fujian's top bureau director and deputy director, all working with him to smuggle in more than 53 billion RMB (7.8 billion USD) worth of contraband across China's southeastern border (Shieh 2005). His political influence was rumored to extend beyond provincial leaders in Fujian all the way to Beijing's central government. Seeking political asylum in Canada, where he had fled in 1999 amid a sweeping anti-smuggling campaign against his operation, Lai claimed to be a victim of a political power struggle among China's top leaders in Beijing. Moreover, as an archetypical man who knew too much, he argued that in his exile, he had become a political threat to many still in power in China whom he could implicate in corruption from afar and who he said “want to get me back so they can shut me up for good” (Beech 2002).
Returned in handcuffs to China on the same day that the two bullet trains crashed, Lai soon became the center of a popular “wag the dog” conspiracy theory linking corruption in the Railway Ministry to the not-so-distant failings of Fujian Customs.
The aim of this study was to describe previously unrecognised or under-recognised adverse events associated with Melody® valve implantation.
In rare diseases and conditions, it is typically not feasible to conduct large-scale safety trials before drug or device approval. Therefore, post-market surveillance mechanisms are necessary to detect rare but potentially serious adverse events.
We reviewed the United States Food and Drug Administration’s Manufacturer and User Facility Device Experience (MAUDE) database and conducted a structured literature review to evaluate adverse events associated with on- and off-label Melody® valve implantation. Adverse events were compared with those described in the prospective Investigational Device Exemption and Post-Market Approval Melody® transcatheter pulmonary valve trials.
We identified 631 adverse events associated with “on-label” Melody® valve implants and 84 adverse events associated with “off-label” implants. The most frequent “on-label” adverse events were similar to those described in the prospective trials including stent fracture (n=210) and endocarditis (n=104). Previously unrecognised or under-recognised adverse events included stent fragment embolisation (n=5), device erosion (n=4), immediate post-implant severe valvar insufficiency (n=2), and late coronary compression (n=2 cases at 5 days and 3 months after implantation). Under-recognised adverse events associated with off-label implantation included early valve failure due to insufficiency when implanted in the tricuspid position (n=7) and embolisation with percutaneous implantation in the mitral position (n=5).
Post-market passive surveillance does not demonstrate a high frequency of previously unrecognised serious adverse events with “on-label” Melody® valve implantation. Further study is needed to evaluate safety of “off-label” uses.
Kuratite, ideally Ca4(Fe2+10Ti2)O4[Si8Al4O36], the Fe2+-analogue of rhönite and a new member of the sapphirine supergroup, was identified from the D'Orbigny angrite meteorite by electron microscopy and micro-Raman spectroscopy. Based on the least-squares refinement of 25 d-spacings measured from selected-area electron diffraction patterns of 11 zone axes, the symmetry of kuratite was shown to be triclinic (space group by analogy to rhönite) with a = 10.513(7), b = 10.887(7), c = 9.004(18) Å, α = 105.97(13), β = 96.00(12), γ = 124.82(04)°, V = 767 ± 2 Å3 and Z = 1 for the 40 oxygen formula. The empirical formula based on eight electron microprobe analyses is (Ca3.88Na0.02REE3+0.03Mn0.03Mg0.01Ni0.02Zn0.01Sr0.01)∑4.01 (Fe2+9.989.9Ti2.00)∑11.98(Si7.80Al3.52Fe3+0.64P0.05S0.02)∑12.03O39.98F0.01Cl0.01. The simplified formula is Ca4(Fe2+10Ti2)O4[Si8Al4O36]. Micro-Raman spectroscopy showed four main bands resembling those of lunar rhönite but with higher frequencies due to different chemical composition. Analogous to the occurrence of kuratite in terrestrial basaltic rocks, kuratite coexisting with Al, Ti-bearing hedenbergite, ulvöspinel, iron-sulfide, tsangpoite, Ca-rich fayalite and kirschsteinite in D'Orbigny angrite most probably was formed at >1000°C by rapid cooling of an interstitial melt, which is subsilicic, almost Mg-free but enriched in Al-P-Ca-Ti-Fe.
The fast stellar winds can blow bubbles in the circumstellar material ejected from previous phases of stellar evolution. These are found at different scales, from planetary nebulae (PNe) around stars evolving to the white dwarf stage, to Wolf-Rayet (WR) bubbles and up to large-scale bubbles around massive star clusters. In all cases, the fast stellar wind is shock-heated and a hot bubble is produced. Processes of mass evaporation and mixing of nebular material and heat conduction occurring at the mixing layer between the hot bubble and the optical nebula are key to determine the thermal structure of these bubbles and their evolution. In this contribution we review our current understanding of the X-ray observations of hot bubbles in PNe and present the first spatially-resolved study of a mixing layer in a PN.
The aim of the study was to evaluate the trends in respiratory syncytial virus-related hospitalisations and associated outcomes in children with haemodynamically significant heart disease in the United States of America.
The Kids’ Inpatient Databases (1997–2012) were used to estimate the incidence of respiratory syncytial virus hospitalisation among children ⩽24 months with or without haemodynamically significant heart disease. Weighted multivariable logistic regression and chi-square tests were used to evaluate the trends over time and factors associated with hospitalisation, comparing eras before and after publication of the 2003 American Academy of Pediatrics palivizumab immunoprophylaxis guidelines. Secondary outcomes included in-hospital mortality, morbidity, length of stay, and cost.
Overall, 549,265 respiratory syncytial virus-related hospitalisations were evaluated, including 2518 (0.5%) in children with haemodynamically significant heart disease. The incidence of respiratory syncytial virus hospitalisation in children with haemodynamically significant heart disease decreased by 36% when comparing pre- and post-palivizumab guideline eras versus an 8% decline in children without haemodynamically significant heart disease (p<0.001). Children with haemodynamically significant heart disease had higher rates of respiratory syncytial virus-associated mortality (4.9 versus 0.1%, p<0.001) and morbidity (31.5 versus 3.5%, p<0.001) and longer hospital length of stay (17.9 versus 3.9 days, p<0.001) compared with children without haemodynamically significant heart disease. The mean cost of respiratory syncytial virus hospitalisation in 2009 was $58,166 (95% CI:$46,017, $70,315).
These data provide stakeholders with a means to evaluate the cost–utility of various immunoprophylaxis strategies.