To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure firstname.lastname@example.org
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
In this paper, a novel single-cavity triangular substrate-integrated waveguide (TSIW) dual-band filter loading a complementary triangular split ring resonator (CTSRR) is proposed, which has three transmission zeros (TZs) in the stopband in total. The dual-band response is achieved by the CTSRR and the degenerate modes of the TSIW cavity. In order to control the TZs, we propose two adjustment techniques, shift feeding technique and adding via perturbation. In addition, the CTSRR etched on the surface can produce a new TZ in the upper first-passband. Finally, a dual-band filter with three TZs is simulated, fabricated, and measured. There is a good agreement between the simulated results and measured ones.
Previous studies have demonstrated that type 1 diabetes mellitus (T1DM) could be triggered by an early childhood infection. Whether maternal infection during pregnancy is associated with T1DM in offspring is unknown. Therefore, we aimed to study the association using a systematic review and meta-analysis. Eighteen studies including 4304 cases and 25 846 participants were enrolled in this meta-analysis. Odds ratios (ORs) and 95% confidence intervals (CIs) were synthesised using random-effects models. Subgroup analyses and sensitivity analyses were conducted to assess the robustness of associations. Overall, the pooled analysis yielded a statistically significant association between maternal infection during pregnancy and childhood T1DM (OR 1.31, 95% CI 1.07–1.62). Furthermore, six studies that tested maternal enterovirus infection showed a pooled OR of 1.54 (95% CI 1.05–2.27). Heterogeneity from different studies was evident (I2 = 70.1%, P < 0.001) and was mainly attributable to the different study designs, ascertaining methods and sample size among different studies. This study provides evidence for an association between maternal infection during pregnancy and childhood T1DM.
We report on a novel processing route to prepare La0.8Ce0.2(Fe0.95Co0.05)11.8Si1.2/Cu bulk composites by low-temperature hot pressing. With increasing copper content, the compressive strength of the composites first decrease and then increase owing to the buffering effect of copper, but the magnetocaloric effect reduces to some extent. Copper addition improves the thermal conductivity of the composites, which compensates for the decrease in thermal conductivity due to porosity. A relatively large entropy change of 5.75–7.19 J/(kg K) at 2 T near the Curie temperature (249 K), good thermal conductivity of 7.51–15.55 W/(m·K), and improved compressive strength of 151.1–248.0 MPa make these composites attractive magnetic refrigeration materials.
Propeller synchrophasing control is an active method to reduce the noise and vibration of turboprop aircraft without additional weight and power. Phase control accuracy has a great influence on the noise reduction effect of synchrophasing. An integrated power/speed/synchrophasing control strategy is proposed to improve the control precision. Speed/phase control transformation logic based on a multi-blade phase plane is adopted which can take both the rapidity of speed response and phase control precision into account, but there exists switching oscillation during the mode transform process. In order to suppress the phase fluctuation due to exterior disturbance, a slave-slave control scheme is provided to take place of a master-slave scheme. Simulation results based on an integrated turboprop engine/propeller real-time non-linear model show that speed/phase integration logic can improve the response rapidity of both the speed and phase. The precision of the control system is verified to be in acceptable range.
Introduction: The GridlockED game is a serious game aimed at teaching junior learners about flow and organization in the emergency department(ED). With serious games, the mechanism of learning is thought to be via the gameplay experience. Objectives built into gameplay are aimed at teaching players about a specific concept; in this case, we hoped to teach players about interprofessional collaboration and basic mechanics that drive flow in the ED. However, before a player can be taught, he or she must be engaged and have a positive gameplay experience. From the GridlockED gameplay, we aim to explore how a players gameplay experience related to observed actions while playing the game, including participating in decision making and keeping the team organized. Methods: From April-August 2017, participants were invited to play 4 turns of a GridlockED game session. They were video recorded during gameplay. After playing the game, they were surveyed using the previously derived Game Experience Questionnaire (GEQ) to measure their gameplay experience. The videos were reviewed by two research team members (SH, EJ), tallying various observed game actions. We conducted Pearson correlation between players GEQ total score and their observed actions. Results: A total of 32 participants (13 attendings, 5 senior residents, 10 junior residents, and 4 nurses) played the game. The average total GEQ was 67.2/132 (SD=10.7), suggesting most players had a moderately good gameplay experience. The total GEQ score correlated with component subscores within the questionnaire. Overall observed activity correlated well with each observed action subtype. However, the GEQ total score did not correlate significantly with the total observed action (Pearsons r=0.18,p=0.32). GEQ total score was found to be moderately correlated to an observation that a player participated in determining strategy during gameplay (r=0.36,p=0.04). There was a moderate negative correlation between determining strategy during gameplay and teaching about the game (r=-0.37,p=0.04) or emergency medicine concepts (r=-0.47,p<0.01). Conclusion: The GEQ is internally consistent, but does not have a strong relationship to observed actions, suggesting that game experience does not necessarily correlate with observable actions. This suggests that players may be intellectually stimulated or engaged without necessarily completing any observable actions during gameplay.
Introduction: The management of patient flow in the emergency department (ED) is crucial for the practice of emergency medicine (EM). However, this skill is difficult to teach didactically and is learned implicitly in the latter half of residency training. To help expedite the learning process, we developed the GridlockED board game as an educational tool to simulate ED patient flow. By having junior medical trainees play this game, we believe that they will develop a greater understanding of patient flow and resource management in the ED. Additionally, since GridlockED is a cooperative game, players may also benefit by improving their communication and teamwork skills. Methods: GridlockED was developed over twenty months of iterative gameplay and review. Feedback from attending emergency physicians, residents, and medical students was integrated into the game through a Plan-Do-Study-Act (PDSA) model. Emergency medicine nurses, physicians and residents at McMaster University were recruited to play GridlockED. Each player completed a pre-survey to collect demographic data and to assess their prior experience with playing board games. All play sessions were recorded for data collection purposes. Following each game session, a member of the research team conducted an exit interview with the players to gather information about their play experience and the educational value of the game. A post-survey was also sent to each participant for further feedback. Results: Eighteen gameplay sessions were conducted from June to August 2017. A total of thirty-two participants played the game (13 emergency physicians, 15 residents, and four nurses). Overall responses to the post-gameplay survey showed that players endorsed GridlockED as a useful potential teaching tool (75%, n=24/32) and the majority felt that it had the potential to improve patient flow in the ED (56%, n=18/32). Most participants found that the game was easy to play (91%, n=27/29), and that the instructions were clear (87.5%, n=28/32). Respondents also felt that the game reflected real life scenarios (56%, n=18) and that cases reflected the types of patients that they saw in the ED (78%, n=25). Conclusion: Our results have shown an overall positive response to GridlockED, with most participants supporting it as both an engaging board game and potential teaching tool. We believe that future studies with larger sample sizes and medical students will further validate the use of serious games in medical education.
Introduction: With the increasing volume of medical literature published each year, it is difficult for clinicians to translate the latest research into practice. Awareness is the first step of knowledge translation and journals have begun using social media to increase the dissemination and awareness of their publications. Infographics can describe research findings visually, are shared broadly on social media, and may be a more effective way to convey information. We hypothesized that infographic abstracts would increase the social media dissemination and online readership of research articles relative to traditional abstracts. Methods: In this randomized controlled trial, 24 original research articles were chosen from the six issues of the Canadian Journal of Emergency Medicine (CJEM) published between July 2016 and May 2017 (4 articles per issue). Half were randomized to the infographic and control groups within each issue. Infographic articles were promoted using a visual infographic outlining the findings of the article. Control articles were promoted using a screen capture image of each articles abstract. Both were disseminated through the journals social media accounts (Twitter and Facebook) along with the link to the selected article. Infographics were also published on CanadiEM.org. Abstract views, full text views, and the change in Altmetric score were tracked for 30 days and compared between groups. Unpaired two-tailed t-tests were used to detect significant differences. Results: Abstract views (mean, SD) were significantly higher for infographic articles (378.9, 162.0) than control articles (175.5, 69.2, p<0.001). Mean Altmetric scores were significantly higher for infographic articles (26.4, 13.8) than control articles (3.4, 1.7, p<0.0001). There was no statistically significant difference in full-text views between infographic (49.7, 90.4) and control articles (25.3, 12.3). Conclusion: CJEM articles promoted on social media using infographics had higher abstract viewership and Altmetric scores than those promoted with traditional abstracts. Although there was no difference in full-text readership, our results suggest that infographic abstracts may have a role in increasing the dissemination of medical literature.
Four complete platysiagid fish specimens are described from the Luoping Biota, Anisian (Middle Triassic), Yunnan Province, southwest China. They are small fishes with bones and scales covered with ganoine. All characters observed, such as nasals meeting in the midline, a keystone-like dermosphenotic, absence of post-rostral bone, two infraorbitals between dermosphenotic and jugal, large antorbital, and two postcleithra, suggest that the new materials belong to a single, new Platysiagum species, P. sinensis sp. nov. Three genera are ascribed to Platysiagidae: Platysiagum, Helmolepis and Caelatichthys. However, most specimens of the first two genera are imprints or fragmentary. The new, well-preserved specimens from the Luoping Biota provide more detailed anatomical information than before, and thus help amend the concept of the Platysiagidae. The Family Platysiagidae was previously classed in the Perleidiformes. Phylogenetic analysis indicates that the Platysiagidae is a member of basal Neopterygii, and its origin seems to predate that of Perleidiformes. Moreover, platysiagid fishes are known from the Middle Triassic of the western Tethys region. The newly found specimens of platysiagids from Luoping provide additional evidence that both eastern and western sides of the Tethys Ocean were biogeographically more connected than previously thought.
Athetis lepigone (Möschler) (Lepidoptera: Noctuidae) is a new outbreak pest in China. Consequently, it is unclear whether the emergence and spread of the outbreak of this pest are triggered by rapid in situ population size increases in each outbreak area, or by immigrants from a potential source area in China. In order to explore the outbreak process of this pest through a population genetics approach, we developed ten novel polymorphic expressed sequence tags (EST)-derived microsatellites. These new microsatellites had moderately high levels of polymorphism in the tested population. The number of alleles per locus ranged from 3 to 19, with an average of 8.6, and the expected heterozygosity ranged from 0.269 to 0.783. A preliminary population genetic analysis using these new microsatellites revealed a lack of population genetic structure in natural populations of A. lepigone. The estimates of recent migration rate revealed strong gene flow among populations. In conclusion, our study developed the first set of EST-microsatellite markers and shed a new light on the population genetic structure of this pest in China.
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.
Hepatitis C virus (HCV) infection is one of the leading causes of death and morbidity associated with liver disease. Risk factors identified for the transmission of HCV include contaminated blood products, intravenous drug use, body piercing, an infected mother at birth, sexual activity, and dental therapy, among others. However, the exact diversity of the HCV genotype and genetic variation among patients with low-risk factors is still unknown. In this study, we briefly described and analysed the genotype distribution and genetic variation of HCV infections with low-risk factors using molecular biology techniques. The results suggested that genotype 1b was predominant, followed by genotypes 2a and 1a. Genetic variations in the 5′ UTR sequences of HCV were identified, including point mutations, deletions, and insertions. The frequency of genetic variations in 1b was higher than in 2a. This study provides considerable value for the prevention and treatment of liver disease caused by HCV among patients with low-risk factors and for the development of HCV diagnostic reagents and vaccines.
Understanding the organic chemistry of molecular clouds, particularly the formation of biologically important molecules, is fundamental to the study of the processes which lead to the origin, evolution and distribution of life in the Galaxy. Determining the level of molecular complexity attainable in the clouds, and the nature of the complex organic material available to protostellar disks and the planetary systems that form from them, requires an understanding of the possible chemical pathways and is therefore a central question in astrochemistry. We have thus searched for prebiologically important molecules in the hot molecular cloud cores: Sgr B2(N-LMH), W51 e1/e2 and Orion-KL. Among the molecules searched: Pyrimidine is the unsubstituted ring analogue for three of the DNA and RNA bases. 2H-Azirine and Aziridine are azaheterocyclic compounds. And Glycine is the simplest amino acid. Detections of these interstellar organic molecular species will thus have important implications for Astrobiology. Our preliminary results indicate a tentative detection of interstellar glycine. If confirmed, this will be the first detection of an amino acid in interstellar space and will greatly strengthen the thesis that interstellar organic molecules could have played a pivotal role in the prebiotic chemistry of the early Earth.
In rock engineering, evaluating the post-peak strength and deformation of rock is necessary. To explore the elasto-plastic behavior of sandstone in the post-peak stage, a series of strain-controlled triaxial tests were conducted under different confining pressures. According to the post-peak characteristics, a constitutive model based on nonlinear elasticity and generalized plasticity is proposed. This proposed model is characterized by the following features: (1) Nonlinear elasticity is observed under hydrostatic and shear loading; (2) the associated flow rule is followed; (3) substantial plastic deformation occurs during shear loading; and (4) post-peak softening behavior is accurately predicted. This model requires twelve material parameters, three for elasticity and nine for plasticity. The proposed model was validated by comparing the triaxial test results of Mushan sandstone at different hydrostatic pressures under dry and saturated conditions. In addition, the model is versatile; it can simulate the deformational behavior of two other sandstones. In summary, the proposed model can reasonably predict the complete stress–strain curve of sandstone.
Using the spectroscopic distances of over 0.12 million A-type stars selected from the LAMOST Spectroscopic Survey of the Galactic Anti-center (LSS-GAC), we map their three-dimensional number density distributions in the Galaxy. These stellar number density maps allow an investigation of the Galactic young age thin disk structure with no a priori assumptions about the functional form of its components. The data show strong evidence for a significant flaring young disk. A more detail analysis show that the stellar flaring have different behaviours between the Northern and the Southern Galactic disks. The maps also reveal spatially coherent, kpc-scale stellar substructure in the thin disk. Finally, we detect the Perseus arm stellar overdensity at R ~ 10 kpc.
Using the data from the LAMOST Galactic spectroscopic surveys and some other surveys, we have started a series of work to measure the mass distribution of our Galaxy. As a result of the first-stage, we have constructed the Galactic rotation curve out to 100 kpc and the Galactic escape velocity curve between 5 and 14 kpc. From the two curves, we have built parametrized mass models for our Galaxy, respectively. Both models yield a similar result for the Milky Way's virial mass: ~ 0.9 × 1012 M⊙.
Although specific phobia is highly prevalent, associated with impairment, and an important risk factor for the development of other mental disorders, cross-national epidemiological data are scarce, especially from low- and middle-income countries. This paper presents epidemiological data from 22 low-, lower-middle-, upper-middle- and high-income countries.
Data came from 25 representative population-based surveys conducted in 22 countries (2001–2011) as part of the World Health Organization World Mental Health Surveys initiative (n = 124 902). The presence of specific phobia as defined by the Diagnostic and Statistical Manual of Mental Disorders, fourth edition was evaluated using the World Health Organization Composite International Diagnostic Interview.
The cross-national lifetime and 12-month prevalence rates of specific phobia were, respectively, 7.4% and 5.5%, being higher in females (9.8 and 7.7%) than in males (4.9% and 3.3%) and higher in high- and higher-middle-income countries than in low-/lower-middle-income countries. The median age of onset was young (8 years). Of the 12-month patients, 18.7% reported severe role impairment (13.3–21.9% across income groups) and 23.1% reported any treatment (9.6–30.1% across income groups). Lifetime co-morbidity was observed in 60.5% of those with lifetime specific phobia, with the onset of specific phobia preceding the other disorder in most cases (72.6%). Interestingly, rates of impairment, treatment use and co-morbidity increased with the number of fear subtypes.
Specific phobia is common and associated with impairment in a considerable percentage of cases. Importantly, specific phobia often precedes the onset of other mental disorders, making it a possible early-life indicator of psychopathology vulnerability.
Dengue fever (DF) is the most prevalent and rapidly spreading mosquito-borne disease globally. Control of DF is limited by barriers to vector control and integrated management approaches. This study aimed to explore the potential risk factors for autochthonous DF transmission and to estimate the threshold effects of high-order interactions among risk factors. A time-series regression tree model was applied to estimate the hierarchical relationship between reported autochthonous DF cases and the potential risk factors including the timeliness of DF surveillance systems (median time interval between symptom onset date and diagnosis date, MTIOD), mosquito density, imported cases and meteorological factors in Zhongshan, China from 2001 to 2013. We found that MTIOD was the most influential factor in autochthonous DF transmission. Monthly autochthonous DF incidence rate increased by 36·02-fold [relative risk (RR) 36·02, 95% confidence interval (CI) 25·26–46·78, compared to the average DF incidence rate during the study period] when the 2-month lagged moving average of MTIOD was >4·15 days and the 3-month lagged moving average of the mean Breteau Index (BI) was ⩾16·57. If the 2-month lagged moving average MTIOD was between 1·11 and 4·15 days and the monthly maximum diurnal temperature range at a lag of 1 month was <9·6 °C, the monthly mean autochthonous DF incidence rate increased by 14·67-fold (RR 14·67, 95% CI 8·84–20·51, compared to the average DF incidence rate during the study period). This study demonstrates that the timeliness of DF surveillance systems, mosquito density and diurnal temperature range play critical roles in the autochthonous DF transmission in Zhongshan. Better assessment and prediction of the risk of DF transmission is beneficial for establishing scientific strategies for DF early warning surveillance and control.
Public controversy regarding the potential overdiagnosis and overmedication of children with attention-deficit/hyperactivity disorder (ADHD) has continued for decades. This study used the National Health Insurance Research Database of Taiwan (NHIRD-TW) to explore trends in ADHD diagnosis in youths and the proportion of those receiving medication, with the aim of determining whether ADHD is overdiagnosed and overmedicated in Taiwan.
Youths (age ≤18 years) who had at least two NHIRD-TW claims records with ADHD diagnosis between January 2000 and December 2011 were selected as the subject cohort. In total, the study sample comprised 145 018 patients with ADHD (mean age at a diagnosis of ADHD: 7.7 ± 3.1 years; 21.4% females). The number of cases of ADHD were calculated annually for each year (from 2000 to 2011), and the number of cases per year who received medication was determined as those with at least one record of pharmacotherapy (immediate-release methylphenidate, osmotic controlled-release formulation of methylphenidate, and atomoxetine) in each year.
The prevalence rates of a diagnosis of ADHD in the youths ranged from 0.11% in 2000 to 1.24% in 2011. Compared with children under 6 years of age, the ADHD diagnosis rates in children aged between 7 and 12 years (ratio of prevalence rates = 4.36) and in those aged between 13 and 18 years (ratio of prevalence rates = 1.42) were significantly higher during the study period. The prevalence in males was higher than that in females (ratio of prevalence rates = 4.09). Among the youths with ADHD, 50.2% received medications in 2000 compared with 61.0% in 2011. The probability of receiving ADHD medication increased with age. More male ADHD patients received medications that females patients (ratio of prevalence rates = 1.16).
The rate of ADHD diagnosis was far lower than the prevalence rate (7.5%) identified in a previous community study using face-to-face interviews. Approximately 40–50% of the youths with ADHD did not receive any medications. These findings are not consistent with a systematic public opinion about overdiagnosis or overmedication of ADHD in Taiwan.
The molecular mechanism underlying the yellow seed trait has been a subject of quality breeding in Brassica. Thus, uncovering the biosynthetic pathway of proanthocyanidin (PA) accumulation in the Brassica seed coat is a promising research programme. Arabidopsis thaliana BANYULS (BAN) encodes anthocyanidin reductase, which is involved in seed coat pigmentation. In the current study, 2 and 4 BAN homologues were isolated using one pair of primers from Brassica nigra and Brassica juncea, respectively. Reverse transcription polymerase chain reaction (PCR) analysis showed that BAN was expressed abundantly in the seed coat of black seeds and in the embryos of all lines, but not in the seed coat of yellow seeds. Primers incorporating B genome-specific nucleotide variations were designed according to previously published BAN gene sequences of Brassica species to discern the BAN sequence located in B genome origin of Brassica using allele-specific PCR amplification. Proanthocyanidins were also detected by p-dimethylaminocinnamaldehyde staining and a butanol–hydrochloric acid (BuOH–HCl) colorimetric assay in the seed coat of black seeds, but not in the seed coat of yellow seeds. Anthocyanins were not also detected in the seed coat of Brassica species by the BuOH–HCl assay. Both transcriptional and chemical analyses suggested that BAN genes could be involved in both the biosynthesis of PAs and colour formation in the seed coat of Brassica species, whereas no expression of the BAN gene could block biosynthesis of PAs in the yellow seed coat.