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We report the dielectric properties of ACu3Ti4O12 (A = Eu2/3, Tb2/3, and Na1/2Eu1/2) (ACTO) in the frequency range of 40 Hz–2.5 MHz and in the temperature range of 293–473 K. The experimental results show that substituting for Ca improves the loss tangent of CaCu3Ti4O12 (CCTO). Although the dielectric constants largely decrease, they remain at a high level of 103. To identify the observed dielectric performances of ACTO, scanning electron microscopy and complex impedance measurements were conducted. The conducting mechanism for the grain of ACTO was found to be ion jumping rather than electron hopping (for the grain of CCTO). The results show that the decreased dielectric constant may be related to the decreased grain size, the different carrier in the grain, the different grain boundary properties, or a combination of these factors. All these factors are associated with the deficiency of oxygen vacancies in the samples of ACTO. The decreased loss tangent may be due to the increase in the grain boundary resistance.
We describe the case of an 11-month-old girl with a rare cerebellar glioblastoma driven by a NACC2-NTRK2 (Nucleus Accumbens Associated Protein 2-Neurotrophic Receptor Tyrosine Kinase 2) fusion. Initial workup of our case demonstrated homozygous CDKN2A deletion, but immunohistochemistry for other driver mutations, including IDH1 R132H, BRAF V600E, and H3F3A K27M were negative, and ATRX was retained. Tissue was subsequently submitted for personalized oncogenomic analysis, including whole genome and whole transcriptome sequencing, which demonstrated an activating NTRK2 fusion, as well as high PD-L1 expression, which was subsequently confirmed by immunohistochemistry. Furthermore, H3 and IDH demonstrated wildtype status. These findings suggested the possibility of treatment with either NTRK- or immune checkpoint- inhibitors through active clinical trials. Ultimately, the family pursued standard treatment that involved Head Start III chemotherapy and proton radiotherapy. Notably, at most recent follow upapproximately two years from initial diagnosis, the patient is in disease remission and thriving, suggesting favorable biology despite histologic malignancy. This case illustrates the value of personalized oncogenomics, as the molecular profiling revealed two actionable changes that would not have been apparent through routine diagnostics. NTRK fusions are known oncogenic drivers in a range of cancer types, but this is the first report of a NACC2-NTRK2 fusion in a glioblastoma.
This presentation will enable the learner to:
1.Explore the current molecular landscape of pediatric high grade gliomas
2.Recognize the value of personalized oncogenomic analysis, particularly in rare and/or aggressive tumors
3.Discuss the current status of NTRK inhibitor clinical trials
This paper considers the integrated guidance and control (IGC) problem for impact angle constrained interception against manoeuvring targets with actuator saturation constraint. Based on the backstepping technique, an adaptive IGC law is presented to address this problem, where a fixed-time differentiator is proposed to estimate the derivatives of virtual control inputs to avoid the inherent problem of “explosion of complexity” suffered by the typical backstepping. Furthermore, an auxiliary first-order filter is introduced into the IGC law to cope with the actuator saturation constraint. The stability of the closed-loop system is strictly proved. Finally, the superiority of the proposed IGC law is verified by comparison simulations.
This study aims to investigate the prevalence and genotype distribution of anal human papillomavirus (HPV) infection among men with different sexual orientations with or without human immunodeficiency virus (HIV) in China. A cross-sectional study was conducted during 2016–2017 in Taizhou City, Zhejiang Province. Convenient sampling was used to recruit male participants from HIV voluntary counselling and testing clinics and Center for Disease Control and Prevention. A face-to-face questionnaire interview was administered and an anal-canal swab was collected for HPV genotyping. A total of 160 HIV-positive and 113 HIV-negative men participated in the study. The prevalence of any type HPV was 30.6% for heterosexual men, 74.1% for homosexual and 63.6% for bisexual men among HIV-positive participants, while the prevalence was 8.3%, 29.2% and 23.8% respectively among HIV-negatives. The most prevalent genotypes were HPV-58 (16.9%), HPV-6 (15.6%) and HPV-11 (15.0%) among HIV-positive men, and were HPV-16 (4.4%), HPV-52 (4.4%) and HPV-6 (3.5%) among HIV-negative men. Having ever had haemorrhoids and having ever seen blood on tissue after defaecation was associated with HPV infection. One-fourth of the HPV infections in this study population can be covered by the quadrivalent vaccine in market. The highly prevalent anal HPV infection among men especially HIV-infected men calls for close observation and further investigation for anal cancer prevention.
A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of
in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity
at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of
focused to intensities
High-energy electron radiography (HEER) has been proposed for time-resolved imaging of materials, high-energy density matter, and for inertial confinement fusion. The areal-density resolution, determined by the image intensity information is critical for these types of diagnostics. Preliminary experimental studies for different materials with the same thickness and the same areal-density target have been imaged and analyzed. Although there are some discrepancies between experimental and theory analysis, the results show that the density distribution can indeed be attained from HEER. The reason for the discrepancies has been investigated and indicates the importance of the uniformity in the transverse distribution beam illuminating the target. Furthermore, the method for generating a uniform transverse distribution beam using octupole magnets was studied and verified by simulations. The simulations also confirm that the octupole field does not affect the angle-position correlation in the center part beam, a critical requirement for the imaging lens. A more practical method for HEER using collimators and octupoles for generating more uniform beams is also described. Detailed experimental results and simulation studies are presented in this paper.
Vessel flexure can be triggered naturally by surgical operation, heart pulsation and body movement. It may affect the mechanical behavior of the stent and the existence of a stent may in turn cause vessel injury. In the present study, the finite element method is employed to study the interaction between stent and vessel during vessel flexure. Two- and four-link stents made of stainless steel 316L and magnesium alloy WE43 are considered. Results indicate that longitudinal deformation of the stent can be caused by vessel flexure, and the higher levels of stress exist in the link struts. The existence of the stent could induce significant stress concentration and straightened deformation on vessel wall in the course of vessel flexure. Stents with more links or made of harder materials show greater anti-deformation capability, thus inducing a more severe stress concentration and straightened deformation on the vessel wall. The bending direction also affects the mechanical performance of the vessel-stent system. The results obtained could provide useful information for better stent designs and clinical decisions.
Extensive insecticide use has led to the resistance of mosquitoes to these insecticides, posing a major barrier to mosquito control. Previous Solexa high-throughput sequencing of Culex pipiens pallens in the laboratory has revealed that the abundance of a novel microRNA (miRNA), miR-13664, was higher in a deltamethrin-sensitive (DS) strain than a deltamethrin-resistant (DR) strain. Real-time quantitative PCR revealed that the miR-13664 transcript level was lower in the DR strain than in the DS strain. MiR-13664 oversupply in the DR strain increased the susceptibility of these mosquitoes to deltamethrin, whereas inhibition of miR-13664 made the DS strain more resistant to deltamethrin. Results of bioinformatic analysis, quantitative reverse-transcriptase polymerase chain reaction, luciferase assay and miR mimic/inhibitor microinjection revealed CpCYP314A1 to be a target of miR-13664. In addition, downregulation of CpCYP314A1 expression in the DR strain reduced the resistance of mosquitoes to deltamethrin. Taken together, our results indicate that miR-13664 could regulate deltamethrin resistance by interacting with CpCYP314A1, providing new insights into mosquito resistance mechanisms.
Cereal grains treated with organic acids were proved to increase ruminal resistant starch and can relieve the risk of ruminal acidosis. However, previous study mainly focussed on acid-treated barley, the effects of organic acid-treated corn is still unknown. The objectives of this study were to evaluate whether feeding ground corn steeped in citric acid (CA) would affect ruminal pH and fermentation patterns, milk production and innate immunity responses in dairy goats. Eight ruminally cannulated Saanen dairy goats were used in a crossover designed experiment. Each experimental period was 21 day long including 14 days for adaption to new diet and 7 days for sampling and data collection. The goats were fed high-grain diet contained 30% hay and 70% corn-based concentrate. The corn was steeped either in water (control) or in 0.5% (wt/vol) CA solution for 48 h. Goats fed CA diet showed improved ruminal pH status with greater mean and minimum ruminal pH, and shorter (P<0.05) duration of ruminal pH<5.6 and less area of ruminal pH<5.6, 5.8 and 6.0. Concentration of total volatile fatty acid and molar proportion of propionate were less but the molar proportion of acetate was greater (P<0.05) in goats fed the CA diet than the control diet. Concentration of ruminal lipopolysaccharide (LPS) was lower (P<0.05) and that of lactic acid also tended (P<0.10) to be lower in goats fed CA than the control. Although dry matter intake, actual milk yield, yield and content of milk protein and lactose were not affected, the milk fat content and 4% fat-corrected milk tended (P<0.10) to be greater in goats fed CA diet. For the inflammatory responses, peripheral LPS did not differ, whereas the concentration of LPS binding protein and serum amyloid A tended (P<0.10) to be less in goats fed CA diet. Similarly, goats fed CA diet had less (P<0.05) concentration of haptoglobin and tumour necrosis factor. These results indicated that feeding ground corn treated with CA effectively improved ruminal pH status, thus alleviated the risk of ruminal acidosis, reduced inflammatory response, and tend to improve milk yield and milk fat test.
Brain tumor behavior is driven by aberrations in the genome and epigenome. Many of these changes, such as IDH mutations in diffuse low-grade glioma (DLGG), are common amongst the same class of tumour and can be incorporated into the diagnostic criteria. However, any given tumor may have other, less common genomic aberrations that are essential for its biological behavior and may inform on underlying aberrant cellular pathways, and potential therapeutic agents. Precision oncology is a genomics-based approach which profiles these alterations to better manage cancer patients and has established itself within the practice of oncology and is slowly making its way into neuro-oncology. The BC Cancer’s Personalized OncoGenomics (POG) program has profiled 16 adult tumours originating from the central nervous system using whole genome and transcriptome analysis (WGTA), for the first time, within a meaningful clinical timeframe/setting. As expected, primary genomic drivers were consistent with their respective diagnoses, though secondary drivers were found to be unique to each tumour. Although these analyses did not result in altered clinical management for these patients, primarily due to availability of drug or clinical trials, they highlight the heterogeneity of secondary drivers in cancers and provide clinicians with meaningful biological information. Lastly, the data generated by POG has highlighted the frequency and complexity of novel driver fusions which are predicted to behave similarly to canonical driver events in their respective tumours. The information available to clinicians through POG has provided paramount knowledge into the biology of each unique tumour.
A numerical study was undertaken to investigate the mechanical properties of metal-ceramic multilayer micro-pillars under compression. The model system contains alternating layers of aluminum (Al) and silicon carbide (SiC) above a thick silicon (Si) substrate. The finite element analyses show that the pillar deformed in a non-uniform manner under compression, especially when a tapered side wall was included in the model. The heterogeneous feature of the structure plays a significant role in influencing the apparent stress-strain response. The elastic property of the pillar compares favorably with the true composite modulus, but a large discrepancy was found in the plastic response. The difference in deformation behavior between homogeneous pillars and multilayer pillars, along with other geometric effects, were examined in detail.
Here a compact three orthogonal planes high-energy electron radiography system was proposed. One of the critical technologies, the ultra-fast beam bunches split from the bunch train are studied. The separated bunches could be transported to the three orthogonal planes of the target for dynamic radiography diagnostics. The key elements of the ultra-fast bunches split system are transverse deflecting cavity (TDC) and the twin septum magnet (TSM). The principle of TDC and TSM are briefly introduced. An example of the beam bunches split system for test experiment (40 MeV electron beam) with TDC and TSM is designed and studied by particle-tracking simulation and it confirms this method is valid and feasible. Especially with TSM, a compact three orthogonal planes radiography system can be realized. The evolution of the beam parameters along the beam line from simulation are investigated. The detailed design of the beam split system and beam dynamics simulation study are presented in this paper.
Winter wheat (Triticum aestivum L.) production on the Loess Plateau in China has been threatened by water scarcity and climate change during the last decade. Sustainable crop production in this region requires managerial practices that can provide high yield and high water productivity (WP). A 7-year (2001–2008) study at the Loess Plateau Research Station of Lanzhou University investigated the effects of various conservation tillage practices on grain yield, soil water content (SWC), WP and economic return of winter wheat production. Tillage treatments included: conventional tillage (T), conventional tillage followed by stubble retention (TS), no-till (NT) and no-till followed by stubble retention (NTS). Over the entire experimental period, grain yield and WP of winter wheat ranged from 1279 to 4894 kg/ha and 0·32 to 2·41 kg/m3, respectively. Both were significantly affected by tillage treatment and year, while SWC was only affected by year. Grain yield and WP in TS was increased by 4·9, 12·1, 0·9% and 13·7, 20·4 and 3·9% compared with NTS, NT and T, respectively, over seven growing seasons. Additionally, a multiple linear regression analysis indicated that grain yield is mainly limited by SWC during planting. Despite its lower grain yield, the NTS treatment increased economic benefit by US$ 328, US$ 23 and US$ 87/ha compared with TS, NT and T, respectively. Therefore, it is suggested that increasing soil water storage at wheat sowing time and encouraging the use of NTS could improve economic returns in this region.
An experimental investigation into laser ablation of secondary explosives, cyclotetramethylene tetranitramine (HMX), has been carried out by using a solid-state laser at the wavelength of 1064 nm. The ion particles of decomposition were detected by using a time-of-flight mass spectrometer. Possible attributions of both negative ions and positive ions were obtained. Some obvious peaks were found at m/z = 18, 28, 46, 60, and 106, corresponding to H2O, CO/N2/H2CN, NO2, CH2NO2/N2O2, and N(NO2)2/CH2(NO2)2, respectively. According to the distribution of the particles, three possible pathways were proposed to explain the process of particles. The results may shed some light on the possible decomposition mechanism of HMX under laser initiation.
Spatiotemporal analysis is an important tool to monitor changes of tuberculosis (TB) epidemiology, identify high-risk regions and guide resource allocation. However, there are limited data on the contributing factors of TB incidence. This study aimed to investigate the spatiotemporal pattern of TB incidence and its associated factors in mainland China during 2005–2013. Global Moran's I test, Getis-Ord Gi index and heat maps were used to examine the spatial clustering and seasonal patterns. Generalized Linear Mixed Model was applied to identify factors associated with TB incidence. TB incidence presented high geographical variations with two main hot spots, while a generally consistent seasonal pattern was observed with a peak in late winter. Furthermore, we found province-level TB incidence increased with the proportion of the elderly but decreased with Gross Demographic Product per capita and the male:female ratio. Meteorological factors also influenced TB incidence. TB showed obvious spatial clustering in mainland China and both the demographic and socio-economic factors and meteorological measures were associated with TB incidence. These results provide the related information to identify the high-risk districts and the evidence for the government to develop corresponding control measures.
Background: Approximately 12-15% of patients with intracranial aneurysms (IA) have affected first-degree relatives, and are considered to have familial intracranial aneurysms (FIA). Individuals with FIA are at higher risk for aneurysm formation and subarachnoid hemorrhage. THSD1 is the only gene to be associated with nonsyndromic FIA at this time. Our study aims to find rare DNA variants that are major risk factors for FIA in our cohort of patients. Methods: To date we have enrolled 37 affected and 31 unaffected people from 16 families. We have done exome or genome sequencing on at least 1 person from each of 12 families. Results: A rare p.(R686W) variant in THSD1 was found in 1/12 families, but did not cosegregate fully with disease. While less attractive as the primary cause of FIA, we cannot rule out the potential modifying effects of THSD1 p.(R686W) in this family. A second candidate, an extracellular matrix gene within a chromosomal region previously implicated by familial mapping studies, contains rare variants in 4/12 of our families. All four variants are predicted to be damaging. Conclusions: Alongside environmental risk factors, individual FIA families may also have complex rare variant contributions to their disease, such as digenic and multi-locus contributions.
Complex oxides and semiconductors exhibit distinct yet complementary properties owing to their respective ionic and covalent natures. By electrically coupling complex oxides to traditional semiconductors within epitaxial heterostructures, enhanced or novel functionalities beyond those of the constituent materials can potentially be realized. Essential to electrically coupling complex oxides to semiconductors is control of the physical structure of the epitaxially grown oxide, as well as the electronic structure of the interface. Here we discuss how composition of the perovskite A- and B-site cations can be manipulated to control the physical and electronic structure of semiconductor—complex oxide heterostructures. Two prototypical heterostructures, Ba1−xSrxTiO3/Ge and SrZrxTi1−xO3/Ge, will be discussed. In the case of Ba1−xSrxTiO3/Ge, we discuss how strain can be engineered through A-site composition to enable the re-orientable ferroelectric polarization of the former to be coupled to carriers in the semiconductor. In the case of SrZrxTi1−xO3/Ge we discuss how B-site composition can be exploited to control the band offset at the interface. Analogous to heterojunctions between compound semiconducting materials, control of band offsets, i.e., band-gap engineering, provides a pathway to electrically couple complex oxides to semiconductors to realize a host of functionalities.
Longan County is considered a highly endemic area for hepatitis B virus (HBV). The plasma-derived vaccine has been used in newborns in this area since 1987. A cross-sectional survey was conducted to evaluate the long-term effectiveness of this vaccine. In total, 1634 participants born during 1987–1993 and who had received a series of plasma-derived HB vaccinations at ages 0, 1, and 6 months were enrolled. Serological HBV markers were detected and compared with previous survey data. Overall the prevalence of hepatitis B surface antigen (HBsAg) in all participants was 3·79%; 3·47% of subjects who had received the first dose within 24 h were HBsAg positive, and 8·41% of subjects who had received a delayed first dose were also HBsAg positive. There were 1527 subjects identified who had received the first dose within 24 h and whose HBsAg and anti-HBc prevalence increased yearly after immunization, while the anti-HBs-positive rate and vaccine effectiveness declined. The geometric mean concentration of antibody in the anti-HB-positive participants was 55·13 mIU/ml and this declined after immunization. Fewer than 2·0% of participants had anti-HB levels ⩾1000 mIU/ml. The data show that the protective efficacy of the plasma-derived vaccinations declined and administration of HB vaccine within 24 h of birth was very important. To reduce the risk of HBV infection in this highly endemic area, a booster dose might be necessary if anti-HBs levels fall below 10 mIU/ml after age 18 years. Furthermore, studies on the immune memory induced by plasma-derived HB vaccine are needed.
Fosfomycin has become a therapeutic option in urinary tract infections. We identified 57 fosfomycin-resistant Escherichia coli from 465 urine-derived extended-spectrum β-lactamase (ESBL)-producing isolates from a Chinese hospital during 2010–2014. Of the 57 fosfomycin-resistant isolates, 51 (89·5%) carried fosA3, and one carried fosA1. Divergent pulsed-field gel electrophoresis profiles and multi-locus sequence typing results revealed high clonal diversity in the fosA3-positive isolates. Conjugation experiments showed that the fosA3 genes from 50 isolates were transferable, with IncFII or IncI1 being the most prevalent types of plasmids. The high prevalence of fosA3 was closely associated with that of blaCTX-M. Horizontal transfer, rather than clonal expansion, might play a central role in dissemination. Such strains may constitute an important reservoir of fosA3 and blaCTX-M, which may well be readily disseminated to other potential human pathogens. Since most ESBL-producing E. coli have acquired resistance to fluoroquinolones worldwide, further spread of fosA3 in such E. coli isolates should be monitored closely.
Epidemic surveillance is an effective means to determine the characteristics of acute diarrhoea and the benefits of disease control and prevention. The epidemiological, clinical, and aetiological data of adult (aged ⩾15 years) acute diarrhoea in a general hospital in Shanghai were collected and analysed. Out of 2430 acute diarrhoea patients, 162 subjects were sampled (sample ratio 15:1). The sampled subjects had an average age (±s.d.) of 44 ± 18 years; 142 (87·7%) had a history that indicated ingestion of contaminated food; and 40 (24·7%), 54 (33·3%), and 73 (45·1%) patients had diarrhoea that was attributed to viral, bacterial, and unknown aetiological origins respectively. Viral diarrhoea is mainly prevalent during the winter and spring months, while bacterial and diarrhoea of unknown aetiology occur mainly in the summer months. The average age of the unknown aetiology group (48 ± 19 years) was significantly older than that of the viral diarrhoea group (39 ± 16 years). The number of patients with vomiting in the viral group (30·6%) was significantly higher than that in the bacterial (17·1%) and unknown aetiology (8·2%) groups. Viral and bacterial infections are the main cause of acute diarrhoea in Shanghai. However, further effective technological means are needed to improve the surveillance, control, and prevention of acute diarrhoea.