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Spatial epidemiological characteristics and Exponential smoothing model application of Tuberculosis in Qinghai Plateau, China
Y. Shang, T.T. Zhang, Z.F. Wang, B.Z. Ma, N. Yang, Y. T. Qiu, B. Li, Q. Zhang, Q.L. Huang, K.Y. Liu
Journal: Epidemiology & Infection / Accepted manuscript
Published online by Cambridge University Press: 12 January 2022, pp. 1-20
Ice breaking by a high-speed water jet impact
G.-Y. Yuan, B.-Y. Ni, Q.-G. Wu, Y.-Z. Xue, D.-F. Han
Journal: Journal of Fluid Mechanics / Volume 934 / 10 March 2022
Published online by Cambridge University Press: 11 January 2022, A1
Print publication: 10 March 2022
Ice breaking has become one of the main problems faced by ships and other equipment operating in an ice-covered water region. New methods are always being pursued and studied to improve ice-breaking capabilities and efficiencies. Based on the strong damage capability, a high-speed water jet impact is proposed to be used to break an ice plate in contact with water. A series of experiments of water jet impacting ice were performed in a transparent water tank, where the water jets at tens of metres per second were generated by a home-made device and circular ice plates of various thicknesses and scales were produced in a cold room. The entire evolution of the water jet and ice was recorded by two high-speed cameras from the top and front views simultaneously. The focus was the responses of the ice plate, such as crack development and breakup, under the high-speed water jet loads, which involved compressible pressure ${P_1}$ and incompressible pressure ${P_2}$. According to the main cause and crack development sequence, it was found that the damage of the ice could be roughly divided into five patterns. On this basis, the effects of water jet strength, ice thickness, ice plate size and boundary conditions were also investigated. Experiments validated the ice-breaking capability of the high-speed water jet, which could be a new auxiliary ice-breaking method in the future.
Phytohormone dynamics impact fatty acid and oil accumulation during soybean seed maturation
Thien Q. Nguyen, Anna B. Kisiala, Nguyen Ngoc Hai, Suresh Narine, R. J. Neil Emery
Journal: Seed Science Research , First View
Published online by Cambridge University Press: 09 November 2021, pp. 1-14
Fatty acid (FA) levels and profiles are vital for soybean oil quality, while cytokinins (CKs) and abscisic acid (ABA) are potent regulators of plant growth and development. Previous research suggested associations between FA biosynthesis and hormonal signalling networks; however, hormonal regulation of FA accumulation during soybean (Glycine max) seed maturation has never been measured. We analysed hormone and FA profiles obtained from HPLC-(ESI)-MS/MS and GC-FID screening during soybean seed maturation. A multilayered data processing approach, involving heat-maps, principal component analysis (PCA), correlation and multiregression models, suggested a strong relationship between hormone metabolism and FA/oil accumulation during seed maturation. Most strikingly, positive correlations were found between the levels of CK ribosides [transZeatin riboside (tZR), N6-isopentenyladenosine (iPR)] at the early stages of SM (R5-R6) and C18:0, C18:2 and oil content at the R8 stage. Moreover, multiple regression models revealed functional linkages between several CK derivatives and FA and oil content in mature seeds. To further test the significance of hormone regulation in FA metabolism, plants of two soybean accessions with contrasting hormone and FA profiles were sprayed with exogenous ABA and transZeatin (tZ) during the seed-filling period (R5-R6). Depending on the hormone type and concentration, these treatments distinctly modified biosynthesis of all tested FAs, except for C18:0. Most remarkably, tZ (50 nM) promoted production of C16:0, C18:1, C18:2, C18:3, and oil accumulation in maturing seeds. Overall, the results indicate impactful roles for ABA and CKs in FA accumulation during SM and represent a further step towards understanding FA biosynthesis, and potential improvements of soybean oil profiles.
The formation of planetary systems with SPICA
Exploring Astronomical Evolution with SPICA
I. Kamp, M. Honda, H. Nomura, M. Audard, D. Fedele, L. B. F. M. Waters, Y. Aikawa, A. Banzatti, J.E. Bowey, M. Bradford, C. Dominik, K. Furuya, E. Habart, D. Ishihara, D. Johnstone, G. Kennedy, M. Kim, Q. Kral, S.-P. Lai, B. Larsson, M. McClure, A. Miotello, M. Momose, T. Nakagawa, D. Naylor, B. Nisini, S. Notsu, T. Onaka, E. Pantin, L. Podio, P. Riviere Marichalar, W. R. M. Rocha, P. Roelfsema, T. Shimonishi, Y.-W. Tang, M. Takami, R. Tazaki, S. Wolf, M. Wyatt, N. Ysard
Journal: Publications of the Astronomical Society of Australia / Volume 38 / 2021
Published online by Cambridge University Press: 03 November 2021, e055
In this era of spatially resolved observations of planet-forming disks with Atacama Large Millimeter Array (ALMA) and large ground-based telescopes such as the Very Large Telescope (VLT), Keck, and Subaru, we still lack statistically relevant information on the quantity and composition of the material that is building the planets, such as the total disk gas mass, the ice content of dust, and the state of water in planetesimals. SPace Infrared telescope for Cosmology and Astrophysics (SPICA) is an infrared space mission concept developed jointly by Japan Aerospace Exploration Agency (JAXA) and European Space Agency (ESA) to address these questions. The key unique capabilities of SPICA that enable this research are (1) the wide spectral coverage $10{-}220\,\mu\mathrm{m}$ , (2) the high line detection sensitivity of $(1{-}2) \times 10^{-19}\,\mathrm{W\,m}^{-2}$ with $R \sim 2\,000{-}5\,000$ in the far-IR (SAFARI), and $10^{-20}\,\mathrm{W\,m}^{-2}$ with $R \sim 29\,000$ in the mid-IR (SPICA Mid-infrared Instrument (SMI), spectrally resolving line profiles), (3) the high far-IR continuum sensitivity of 0.45 mJy (SAFARI), and (4) the observing efficiency for point source surveys. This paper details how mid- to far-IR infrared spectra will be unique in measuring the gas masses and water/ice content of disks and how these quantities evolve during the planet-forming period. These observations will clarify the crucial transition when disks exhaust their primordial gas and further planet formation requires secondary gas produced from planetesimals. The high spectral resolution mid-IR is also unique for determining the location of the snowline dividing the rocky and icy mass reservoirs within the disk and how the divide evolves during the build-up of planetary systems. Infrared spectroscopy (mid- to far-IR) of key solid-state bands is crucial for assessing whether extensive radial mixing, which is part of our Solar System history, is a general process occurring in most planetary systems and whether extrasolar planetesimals are similar to our Solar System comets/asteroids. We demonstrate that the SPICA mission concept would allow us to achieve the above ambitious science goals through large surveys of several hundred disks within $\sim\!2.5$ months of observing time.
GP.4 Can Quantitative Susceptibility Mapping Help Diagnose and Predict Recovery of Concussion in Children?
N Sader, D Gobbi, B Goodyear, R Frayne, M Beauchamp, WR Craig, Q Doan, R Zemek, KO Yeates, J Riva-Cambrin
Journal: Canadian Journal of Neurological Sciences / Volume 48 / Issue s3 / November 2021
Published online by Cambridge University Press: 05 January 2022, p. S13
Background: Quantitative susceptibility mapping (QSM) is an MR sequence that has potential as a biomarker in concussion. We compared QSM in pediatric concussion patients versus a comparison group of children with orthopedic injuries (OI) and assessed QSM's performance relative to the current clinical benchmark (5P risk score) for predicting persistent postconcussion symptoms (PPCS). Methods: Children (N=967) aged 8-16.99 years with either concussion or OI were prospectively recruited from 5 Canadian centers. Participants completed QSM at a post-acute assessment 2-33 days post-injury. QSM z-score metrics for 9 regions of interest (ROI) were derived from 371 children (concussion=255, OI=116). PPCS at 1-month post-injury was defined using reliable change methods. Results: The concussion and OI groups did not differ significantly in QSM across ROI. Increased frontal white matter (WM) susceptibility predicted reliable increases in parent-rated cognitive symptoms (p=0.001). Together, frontal WM susceptibility and the 5P risk score were better at predicting persistent cognitive symptoms than the 5P risk score alone (p=0.0021). AUC were 0.71(95%CI: 0.62-0.80) for frontal WM susceptibility, 0.67(95%CI: 0.56-0.78) for the 5P risk score, and 0.73(95%CI: 0.64-0.82) for both. Conclusions: This is the first study to demonstrate a potential imaging biomarker that predicts persistent symptoms in children with concussion compared to the current clinical benchmark.
The GLEAM 200-MHz local radio luminosity function for AGN and star-forming galaxies
T. M. O. Franzen, N. Seymour, E. M. Sadler, T. Mauch, S. V. White, C. A. Jackson, R. Chhetri, B. Quici, M. E. Bell, J. R. Callingham, K. S. Dwarakanath, B. For, B. M. Gaensler, P. J. Hancock, L. Hindson, N. Hurley-Walker, M. Johnston-Hollitt, A. D. Kapińska, E. Lenc, B. McKinley, J. Morgan, A. R. Offringa, P. Procopio, L. Staveley-Smith, R. B. Wayth, C. Wu, Q. Zheng
Published online by Cambridge University Press: 06 September 2021, e041
The GaLactic and Extragalactic All-sky Murchison Widefield Array (GLEAM) is a radio continuum survey at 76–227 MHz of the entire southern sky (Declination $<\!{+}30^{\circ}$ ) with an angular resolution of ${\approx}2$ arcmin. In this paper, we combine GLEAM data with optical spectroscopy from the 6dF Galaxy Survey to construct a sample of 1 590 local (median $z \approx 0.064$ ) radio sources with $S_{200\,\mathrm{MHz}} > 55$ mJy across an area of ${\approx}16\,700\,\mathrm{deg}^{2}$ . From the optical spectra, we identify the dominant physical process responsible for the radio emission from each galaxy: 73% are fuelled by an active galactic nucleus (AGN) and 27% by star formation. We present the local radio luminosity function for AGN and star-forming (SF) galaxies at 200 MHz and characterise the typical radio spectra of these two populations between 76 MHz and ${\sim}1$ GHz. For the AGN, the median spectral index between 200 MHz and ${\sim}1$ GHz, $\alpha_{\mathrm{high}}$ , is $-0.600 \pm 0.010$ (where $S \propto \nu^{\alpha}$ ) and the median spectral index within the GLEAM band, $\alpha_{\mathrm{low}}$ , is $-0.704 \pm 0.011$ . For the SF galaxies, the median value of $\alpha_{\mathrm{high}}$ is $-0.650 \pm 0.010$ and the median value of $\alpha_{\mathrm{low}}$ is $-0.596 \pm 0.015$ . Among the AGN population, flat-spectrum sources are more common at lower radio luminosity, suggesting the existence of a significant population of weak radio AGN that remain core-dominated even at low frequencies. However, around 4% of local radio AGN have ultra-steep radio spectra at low frequencies ( $\alpha_{\mathrm{low}} < -1.2$ ). These ultra-steep-spectrum sources span a wide range in radio luminosity, and further work is needed to clarify their nature.
Ear fullness characteristics and prognosis in patients with all-frequency sudden sensorineural hearing loss
E Zhou, X-P Xiao, B Liu, Z-Q Tan, G-Y Miao, X-B Liu, M-X Bu, X Cao, J-Y Zhong
Journal: The Journal of Laryngology & Otology / Volume 135 / Issue 10 / October 2021
Published online by Cambridge University Press: 18 August 2021, pp. 926-931
Print publication: October 2021
This study investigated the characteristics and prognosis of the feeling of ear fullness in patients with unilateral all-frequency sudden sensorineural hearing loss.
Our study included 56 patients with a diagnosis of unilateral all-frequency sudden sensorineural hearing loss accompanied by a feeling of ear fullness and 48 patients without a feeling of ear fullness. The condition of these patients was prospectively observed.
Positive correlations were observed between grading of feeling of ear fullness and hearing loss in patients with a feeling of ear fullness (r = 0.599, p < 0.001). No significant differences were observed in the total effective rate of hearing recovery between patients with and without a feeling of ear fullness after one month of treatment (Z = −0.641, p = 0.521). Eighty-six per cent of patients (48 out of 56) showed complete recovery from the feeling of ear fullness. There was no correlation between feeling of ear fullness recovery and hearing recovery (r = 0.040, p = 0.769).
The prognosis of feeling of ear fullness is good. There was no correlation between feeling of ear fullness recovery and hearing recovery for all-frequency sudden sensorineural hearing loss patients.
Dementia patients have greater anti-cholinergic drug burden on discharge from hospital: A multicentre cross-sectional study
J. Randall, A. Hook, C-M. Grubb, N. Ellis, J. Wellington, A. Hemmad, A. Zerdelis, B. Geers, B. Sykes, C. Auty, C. Vinchenzo, C. Thorburn, D. Asogbon, E. Granger, H. Boagey, J. Raphael, K. Patel, K. Bhargava, M.-K. Dolley, M. Maden, M. Shah, Q. Lee, R. Vaidya, S. Sehdev, S. Barai, S. Roche, U. Khalid, J. Harrison, D. Codling
Journal: European Psychiatry / Volume 64 / Issue S1 / April 2021
Published online by Cambridge University Press: 13 August 2021, pp. S422-S423
Anticholinergic medications block cholinergic transmission. The central effects of anticholinergic drugs can be particularly marked in patients with dementia. Furthermore, anticholinergics antagonise the effects of cholinesterase inhibitors, the main dementia treatment.
This study aimed to assess anticholinergic drug prescribing among dementia patients before and after admission to UK acute hospitals.
352 patients with dementia were included from 17 hospitals in the UK. All were admitted to surgical, medical or Care of the Elderly wards in 2019. Information about patients' prescriptions were recorded on a standardised form. An evidence-based online calculator was used to calculate the anticholinergic drug burden of each patient. The correlation between two subgroups upon admission and discharge was tested with Spearman's Rank Correlation.
Table 1 shows patient demographics. On admission, 37.8% of patients had an anticholinergic burden score ≥1 and 5.68% ≥3. At discharge, 43.2% of patients had an anticholinergic burden score ≥1 and 9.1% ≥3. The increase was statistically significant (rho 0.688; p=2.2x10-16). The most common group of anticholinergic medications prescribed at discharge were psychotropics (see Figure 1). Among patients prescribed cholinesterase inhibitors, 44.9% were also taking anticholinergic medications.
This multicentre cross-sectional study found that people with dementia are frequently prescribed anticholinergic drugs, even if also taking cholinesterase inhibitors, and are significantly more likely to be discharged with a higher anticholinergic drug burden than on admission to hospital.
This project was planned and executed by the authors on behalf of SPARC (Student Psychiatry Audit and Research Collaborative). We thank the National Student Association of Medical Research for allowing us use of the Enketo platform. Judith Harrison was su
Flow structures and heat transport in Taylor–Couette systems with axial temperature gradient
X.-Y. Leng, D. Krasnov, B.-W. Li, J.-Q. Zhong
Journal: Journal of Fluid Mechanics / Volume 920 / 10 August 2021
Published online by Cambridge University Press: 15 June 2021, A42
Print publication: 10 August 2021
We investigate the heat transfer and coherent structures in Taylor–Couette (TC) flows that undergo thermal convection driven by an axially applied temperature gradient. Direct numerical simulations are performed in a Rayleigh number range $10^6 \leq Ra \leq 3 \times 10^8$ for Prandtl number $Pr = 4.38$ and with the shear Reynolds number up to $Re = 10^4$. When the rotation number $R_f$ increases, the flows undergo a transition from buoyancy-dominated ( $R_f<1$) to shear-dominated convection ( $R_f>1$). In the buoyancy-dominated regime with weak rotations, the flow features are similar to those in Rayleigh–Bénard (RB) convection with large-scale plumes emanating from the thermal boundary layers. In this regime, the $Re$-dependence of heat transport $Nu$ is sensitive to $Ra$. We find that for low $Ra$, $Nu$ decreases with increasing $Re$ and becomes independent of $Re$ at high $Ra$. In the shear-dominated regime, the flow structures are characterised by Taylor vortices (TVs), which effectively enhance the heat transport. With sufficiently high Reynolds number for $2000< Re \le 10\,000$, the flow structures are dominated by turbulent TVs, and the transport scaling laws of heat and angular velocity fluxes become independent of buoyancy. We report that in this turbulent regime the axial heat-transport scaling $(Nu\sim Re^{0.578\pm 0.018})$ is consistent with the scaling of radial angular-momentum transport $(Nu_{\omega }\sim Re^{0.581\pm 0.026})$.
Isolator-combustor interactions in a circular model scramjet with thermal and non-thermal choking-induced unstart
D. Baccarella, Q. Liu, B. McGann, G. Lee, T. Lee
Journal: Journal of Fluid Mechanics / Volume 917 / 25 June 2021
Published online by Cambridge University Press: 29 April 2021, A38
Print publication: 25 June 2021
This study investigates the interactions between combustor and isolator and the role played by combustion on choking-induced unstart. Shock train unsteadiness and pressure fluctuations in non-reacting environments have been previously explained in terms of shock-boundary layer interaction and acoustic forcing but, when applied to scramjets, it is still unclear whether and how this picture is altered by combustion effects. The novel experimental set-up used in this study consists of a circular cross-section model scramjet, with optically accessible combustor and isolator, tested in a high-enthalpy hypersonic free stream at Mach 4.5. A comparison is made between cases in which flow choking is induced via thermal (combustion) and non-thermal (mass addition) mechanisms using time-resolved static wall pressure measurements, high-speed flow visualization and planar laser-induced fluorescence of the OH radical as diagnostic tools. Further details on the nature of the interactions observed were provided by experiments performed in a low-enthalpy $\textrm {CO}_2$ free stream at Mach 4 using planar laser scattering visualization. The results revealed remarkable qualitative similarities between unstart processes occurring at high and low enthalpy. At high enthalpy the similarities between thermal and non-thermal choking-induced unstart were both qualitative and quantitative, suggesting very limited effect of combustion on the dynamics of the isolator shock train. Isolator flow unsteadiness, on the other hand, drastically affected the propagation of the pseudo-normal shock in the combustor, but no significant feedback effect on the isolator behaviour was observed.
Epidemiological investigation of recurrent outbreaks of haemolytic uraemic syndrome caused by Shiga toxin-producing Escherichia coli serotype O55:H7 in England, 2014–2018
C. Sawyer, B. Vishram, C. Jenkins, F. Jorgensen, L. Byrne, A. F. W. Mikhail, T. J. Dallman, K. Carroll, L. Ahyow, Q. Vahora, G. Godbole, S. Balasegaram
Journal: Epidemiology & Infection / Volume 149 / 2021
Published online by Cambridge University Press: 19 April 2021, e108
Recurrent outbreaks of haemolytic uraemic syndrome (HUS) caused by Shiga toxin-producing Escherichia coli (STEC) serotype O55:H7 occurred in England between 2014 and 2018. We reviewed the epidemiological evidence to identify potential source(s) and transmission routes of the pathogen, and to assess the on-going risk to public health. Over the 5-year period, there were 43 confirmed and three probable cases of STEC O55:H7. The median age of cases was 4 years old (range 6 months to 69 years old) and over half of all cases were female (28/46, 61%). There were 36/46 (78.3%) symptomatic cases, and over half of all cases developed HUS (25/46, 54%), including two fatal cases. No common food or environmental exposures were identified, although the majority of cases lived in rural or semi-rural environments and reported contact with both wild and domestic animals. This investigation informed policy on the clinical and public health management of HUS caused by STEC other than serotype O157:H7 (non-O157 STEC) in England, including comprehensive testing of all household contacts and household pets and more widespread use of polymerase chain reaction assays for the rapid diagnosis of STEC-HUS.
Endozoochorous seed dispersal of glyphosate-resistant Lolium multiflorum by cattle
C. E. Schaedler, R. M. Scalcon, J. L. C. Viero, D. M. Chiapinotto, D. B. David, F. Q. Rosa, E. B. Azevedo
Journal: The Journal of Agricultural Science / Volume 159 / Issue 3-4 / April 2021
Print publication: April 2021
Lolium multiflorum, one of the most important temperate forage grasses in the world, is used in integrated crop-livestock systems and as a cover crop. However, it is also one of the main weeds in winter crops. The continuous use of glyphosate to manage this species has led to the selection of resistant biotypes (LOLMU-R), making it important to prevent the dispersal of these seeds. This study aimed to assess the recovery and germination of LOLMU-R that have passed through the digestive system of cattle. The experiments were carried out in metabolism cages, using a completely randomized design with six replications. The animals were given 12 112 seeds each, which were recovered from their faeces over a period of 6 days. Germination of the recovered seeds was assessed in a germination chamber and compared against a control (no animal passage). After germination, a glyphosate dose-response curve was constructed. The results obtained showed a total recovery of 1109 seeds (9.1%), with maximum recovery 2 days after ingestion, decreasing to almost zero on day 6. Germination declined linearly as a function of recovery time; however, 4 days after ingestion, germination potential was 18%. The dose-response curve proved the resistance of the recovered seeds. Cattle is a dispersal agent for LOLMU-R seeds, with animals requiring 7 days of quarantine before moving from one infested area to another.
AMOURINS SHELLMOUND: UNCOVERING BIODIVERSITY AND CHRONOLOGY THROUGH CHARCOAL ANALYSES
Kita D Macario, Rita Scheel-Ybert, Natacha Ribeiro-Pinto, Bruna B Pereira, Dayanne Amaral, Eduardo Q Alves
Journal: Radiocarbon / Volume 63 / Issue 4 / August 2021
Published online by Cambridge University Press: 02 March 2021, pp. 1085-1102
Print publication: August 2021
In paleoenvironmental research, several proxies are used to reconstruct climate and vegetation. The establishment of a chronological framework allows for the association of different proxies and correlation of events happening in different geographic areas. Cultural deposits, such as the shellmounds found along the coast of Brazil, play an important role in paleoenvironmental interpretations. Here, we have employed anthracological analysis in charcoal fragments from the Amourins shellmound, located at the margins of the Guanabara Bay, Rio de Janeiro. This allowed for the taxonomic identification and selection of short-lived trees and specific parts of plants for accurate radiocarbon dating. We recorded genera and families typical of the Atlantic Forest, restinga forest, open restinga and mangrove. The 14C ages of charred nuts from different occupational layers range from 3807 ± 35 to 3503 ± 70 BP and a sequential chronological model was built, relating the predominance of mangrove vegetation to the period between 4130–3960 cal BP.
Modelling viscoelastic wave phenomenon by homogenisation of the poroelasticity equations
Q. LI, F. SANTOSA, B. WHEELOCK, K. GOVIL
Journal: European Journal of Applied Mathematics / Volume 32 / Issue 5 / October 2021
Published online by Cambridge University Press: 18 January 2021, pp. 846-864
Poroelastic effects have been of great interest in the seismic literature as they have been identified as a major cause of wave attenuation in heterogeneous porous media. The observed attenuation in the seismic wave can be explained in part by energy loss to fluid motion in the pores. On the other hand, it is known that the attenuation is particularly pronounced in stratified structures where the scale of spatial heterogeneity is much smaller than the seismic wavelength. Understanding of poroelastic effects on seismic wave attenuation in heterogeneous porous media has largely relied on numerical experiments. In this work, we present a homogenisation technique to obtain an upscaled viscoelastic model that captures seismic wave attenuation when the sub-seismic scale heterogeneity is periodic. The upscaled viscoelastic model directly relates seismic wave attenuation to the material properties of the heterogeneous structure. We verify our upscaled viscoelastic model against a full poroelastic model in numerical experiments. Our homogenisation technique suggests a new approach for solving coupled equations of motion.
Evaluation of the frequency of mutation genes in multidrug-resistant tuberculosis (MDR-TB) strains in Beijing, China
Y. Liu, Y. Sun, X. Zhang, Z. Zhang, Q. Xing, W. Ren, C. Yao, J. Yu, B. Ding, S. Wang, C. Li
Published online by Cambridge University Press: 05 January 2021, e21
The aim of this study was to explore the frequency and distribution of gene mutations that are related to isoniazid (INH) and rifampin (RIF)-resistance in the strains of the multidrug-resistant tuberculosis (MDR-TB) Mycobacterium tuberculosis (M.tb) in Beijing, China. In this retrospective study, the genotypes of 173 MDR-TB strains were analysed by spoligotyping. The katG, inhA genes and the promoter region of inhA, in which genetic mutations confer INH resistance; and the rpoB gene, in which genetic mutations confer RIF resistance, were sequenced. The percentage of resistance-associated nucleotide alterations among the strains of different genotypes was also analysed. In total, 90.8% (157/173) of the MDR strains belonged to the Beijing genotype. Population characteristics were not significantly different among the strains of different genotypes. In total, 50.3% (87/173) strains had mutations at codon S315T of katG; 16.8% (29/173) of strains had mutations in the inhA promoter region; of them, 5.5% (15/173) had point mutations at −15 base (C→T) of the inhA promoter region. In total, 86.7% (150/173) strains had mutations at rpoB gene; of them, 40% (69/173) strains had mutations at codon S531L of rpoB. The frequency of mutations was not significantly higher in Beijing genotypic MDR strains than in non-Beijing genotypes. Beijing genotypic MDR-TB strains were spreading in Beijing and present a major challenge to TB control in this region. A high prevalence of katG Ser315Thr, inhA promoter region (−15C→T) and rpoB (S531L) mutations was observed. Molecular diagnostics based on gene mutations was a useful method for rapid detection of MDR-TB in Beijing, China.
The impact of COVID-19 on subthreshold depressive symptoms: a longitudinal study
Y. H. Liao, B. F. Fan, H. M. Zhang, L. Guo, Y. Lee, W. X. Wang, W. Y. Li, M. Q. Gong, L. M. W. Lui, L. J. Li, C. Y. Lu, R. S. McIntyre
Journal: Epidemiology and Psychiatric Sciences / Volume 30 / 2021
Published online by Cambridge University Press: 15 February 2021, e20
Print publication: 2021
The coronavirus disease 2019 (COVID-19) pandemic represents an unprecedented threat to mental health. Herein, we assessed the impact of COVID-19 on subthreshold depressive symptoms and identified potential mitigating factors.
Participants were from Depression Cohort in China (ChiCTR registry number 1900022145). Adults (n = 1722) with subthreshold depressive symptoms were enrolled between March and October 2019 in a 6-month, community-based interventional study that aimed to prevent clinical depression using psychoeducation. A total of 1506 participants completed the study in Shenzhen, China: 726 participants, who completed the study between March 2019 and January 2020 (i.e. before COVID-19), comprised the 'wave 1' group; 780 participants, who were enrolled before COVID-19 and completed the 6-month endpoint assessment during COVID-19, comprised 'wave 2'. Symptoms of depression, anxiety and insomnia were assessed at baseline and endpoint (i.e. 6-month follow-up) using the Patient Health Questionnaire-9 (PHQ-9), Generalised Anxiety Disorder-7 (GAD-7) and Insomnia Severity Index (ISI), respectively. Measures of resilience and regular exercise were assessed at baseline. We compared the mental health outcomes between wave 1 and wave 2 groups. We additionally investigated how mental health outcomes changed across disparate stages of the COVID-19 pandemic in China, i.e. peak (7–13 February), post-peak (14–27 February), remission plateau (28 February−present).
COVID-19 increased the risk for three mental outcomes: (1) depression (odds ratio [OR] = 1.30, 95% confidence interval [CI]: 1.04–1.62); (2) anxiety (OR = 1.47, 95% CI: 1.16–1.88) and (3) insomnia (OR = 1.37, 95% CI: 1.07–1.77). The highest proportion of probable depression and anxiety was observed post-peak, with 52.9% and 41.4%, respectively. Greater baseline resilience scores had a protective effect on the three main outcomes (depression: OR = 0.26, 95% CI: 0.19–0.37; anxiety: OR = 1.22, 95% CI: 0.14–0.33 and insomnia: OR = 0.18, 95% CI: 0.11–0.28). Furthermore, regular physical activity mitigated the risk for depression (OR = 0.79, 95% CI: 0.79–0.99).
The COVID-19 pandemic exerted a highly significant and negative impact on symptoms of depression, anxiety and insomnia. Mental health outcomes fluctuated as a function of the duration of the pandemic and were alleviated to some extent with the observed decline in community-based transmission. Augmenting resiliency and regular exercise provide an opportunity to mitigate the risk for mental health symptoms during this severe public health crisis.
Neutron Star Extreme Matter Observatory: A kilohertz-band gravitational-wave detector in the global network
Gravitational Wave Astronomy
K. Ackley, V. B. Adya, P. Agrawal, P. Altin, G. Ashton, M. Bailes, E. Baltinas, A. Barbuio, D. Beniwal, C. Blair, D. Blair, G. N. Bolingbroke, V. Bossilkov, S. Shachar Boublil, D. D. Brown, B. J. Burridge, J. Calderon Bustillo, J. Cameron, H. Tuong Cao, J. B. Carlin, S. Chang, P. Charlton, C. Chatterjee, D. Chattopadhyay, X. Chen, J. Chi, J. Chow, Q. Chu, A. Ciobanu, T. Clarke, P. Clearwater, J. Cooke, D. Coward, H. Crisp, R. J. Dattatri, A. T. Deller, D. A. Dobie, L. Dunn, P. J. Easter, J. Eichholz, R. Evans, C. Flynn, G. Foran, P. Forsyth, Y. Gai, S. Galaudage, D. K. Galloway, B. Gendre, B. Goncharov, S. Goode, D. Gozzard, B. Grace, A. W. Graham, A. Heger, F. Hernandez Vivanco, R. Hirai, N. A. Holland, Z. J. Holmes, E. Howard, E. Howell, G. Howitt, M. T. Hübner, J. Hurley, C. Ingram, V. Jaberian Hamedan, K. Jenner, L. Ju, D. P. Kapasi, T. Kaur, N. Kijbunchoo, M. Kovalam, R. Kumar Choudhary, P. D. Lasky, M. Y. M. Lau, J. Leung, J. Liu, K. Loh, A. Mailvagan, I. Mandel, J. J. McCann, D. E. McClelland, K. McKenzie, D. McManus, T. McRae, A. Melatos, P. Meyers, H. Middleton, M. T. Miles, M. Millhouse, Y. Lun Mong, B. Mueller, J. Munch, J. Musiov, S. Muusse, R. S. Nathan, Y. Naveh, C. Neijssel, B. Neil, S. W. S. Ng, V. Oloworaran, D. J. Ottaway, M. Page, J. Pan, M. Pathak, E. Payne, J. Powell, J. Pritchard, E. Puckridge, A. Raidani, V. Rallabhandi, D. Reardon, J. A. Riley, L. Roberts, I. M. Romero-Shaw, T. J. Roocke, G. Rowell, N. Sahu, N. Sarin, L. Sarre, H. Sattari, M. Schiworski, S. M. Scott, R. Sengar, D. Shaddock, R. Shannon, J. SHI, P. Sibley, B. J. J. Slagmolen, T. Slaven-Blair, R. J. E. Smith, J. Spollard, L. Steed, L. Strang, H. Sun, A. Sunderland, S. Suvorova, C. Talbot, E. Thrane, D. Töyrä, P. Trahanas, A. Vajpeyi, J. V. van Heijningen, A. F. Vargas, P. J. Veitch, A. Vigna-Gomez, A. Wade, K. Walker, Z. Wang, R. L. Ward, K. Ward, S. Webb, L. Wen, K. Wette, R. Wilcox, J. Winterflood, C. Wolf, B. Wu, M. Jet Yap, Z. You, H. Yu, J. Zhang, J. Zhang, C. Zhao, X. Zhu
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.
Emerging Standards and the Hybrid Model for Organizing Scientific Events During and After the COVID-19 Pandemic
Sara Hanaei, Amirhossein Takian, Reza Majdzadeh, Christopher Ryan Maboloc, Igor Grossmann, Orlando Gomes, Milos Milosevic, Manoj Gupta, Alireza A. Shamshirsaz, Amine Harbi, Amer M. Burhan, Lucina Q. Uddin, Arutha Kulasinghe, Chi-Ming Lam, Seeram Ramakrishna, Abass Alavi, Jan L Nouwen, Tommaso Dorigo, Michael Schreiber, Ajith Abraham, Natalya Shelkovaya, Wojtek Krysztofiak, Majid Ebrahimi Warkiani, Frank Sellke, Shuji Ogino, Francisco J. Barba, Serge Brand, Clara Vasconcelos, Deepak B. Salunke, Nima Rezaei
Journal: Disaster Medicine and Public Health Preparedness , First View
Published online by Cambridge University Press: 26 October 2020, pp. 1-6
Since the beginning of 2020, the coronavirus disease (COVID-19) pandemic has dramatically influenced almost every aspect of human life. Activities requiring human gatherings have either been postponed, canceled, or held completely virtually. To supplement lack of in-person contact, people have increasingly turned to virtual settings online, advantages of which include increased inclusivity and accessibility and a reduced carbon footprint. However, emerging online technologies cannot fully replace in-person scientific events. In-person meetings are not susceptible to poor Internet connectivity problems, and they provide novel opportunities for socialization, creating new collaborations and sharing ideas. To continue such activities, a hybrid model for scientific events could be a solution offering both in-person and virtual components. While participants can freely choose the mode of their participation, virtual meetings would most benefit those who cannot attend in-person due to the limitations. In-person portions of meetings should be organized with full consideration of prevention and safety strategies, including risk assessment and mitigation, venue and environmental sanitation, participant protection and disease prevention, and promoting the hybrid model. This new way of interaction between scholars can be considered as a part of a resilience system, which was neglected previously and should become a part of routine practice in the scientific community.
Magnetic energy dissipation during the current quench of disruption in EAST
Focus on Fusion
T. Tang, L. Zeng, D. L. Chen, R. S. Granetz, S. T. Mao, Y. M. Duan, L. Zhang, H. D. Zhuang, X. Zhu, H. Q. Liu, B. Shen, Y. X. Jie, X. Gao
Journal: Journal of Plasma Physics / Volume 86 / Issue 5 / October 2020
Published online by Cambridge University Press: 08 October 2020, 905860509
A disruption database characterizing the current quench of disruptions with ITER-like tungsten divertor has been developed on EAST. It provides a large number of plasma parameters describing the predisruptive plasma, current quench time, eddy current, and mitigation by massive impurity injection, which shows that the current quench time strongly depends on magnetic energy and post-disruption electron temperature. Further, the energy balance and magnetic energy dissipation during the current quench phase has been well analysed. Magnetic energy is also demonstrated to be dissipated mainly by ohmic reheating and inductive coupling, and both of the two channels have great effects on current quench time. Also, massive gas injection is an efficient method to speed up the current quench and increase the fraction of impurity radiation.
Effect of a training course on the diagnosis of vocal fold leukoplakia by narrow-band imaging
B-G Zhang, J-Q Zhu, W Zhang, F-X Su, G-Q Wang, X-G Ni
Published online by Cambridge University Press: 23 October 2020, pp. 899-904
To investigate the value of narrow-band imaging training for differentiating between benign and malignant vocal fold leukoplakia.
Thirty cases of vocal fold leukoplakia were selected.
Narrow-band imaging endoscopy training had a significant positive effect on the specificity of the differential diagnosis of vocal fold leukoplakia. In addition, the consistency of diagnostic typing of vocal fold leukoplakia by narrow-band imaging improved to 'moderate agreement' following the combination of types I and II and the combination of types IV, V and VI in the typing of vocal fold leukoplakia.
The narrow-band imaging training course may improve the ability of laryngologists to diagnose vocal fold leukoplakia. The new endoscopic diagnostic classification by narrow-band imaging needs to be further simplified to facilitate clinical application.