bluuebunny/crossref_metadata_2025 huggingface dataset:
False testimony: the surveying career of Robert Hamilton Mathews
Authors: Kass Terry
Published: April 2021

The ethnographic recordings of Robert Hamilton Mathews in the late nineteeth and early twentieth centuries have preserved data about Aboriginal language, beliefs, customs, technology and social and family networks. This data has steadily gained increasing respect over more recent decades, and its quality is often attributed to Mathews’ previous career as a property surveyor. Nevertheless, detailed research in the records of the Lands Department of New South Wales held by State Archives of New South Wales reveals a different story—of a man driven to maximise his income using illegal and unethical methods. Official inquiries into Mathews’ conduct by experienced surveyors showed that he often flaunted professional guidelines and practices to such an extent that the influence of Mathew’s surveying career on his ethnographical work should be reconsidered.
Contextualising SARS Coronavirus 2 and COVID-19
Authors: Rawlinson William
Published: April 2021

It is timely to assess where we are in the current SARS Coronavirus-2 pandemic. This edition of Microbiology Australia has national, and international, authorities authoring a series of papers on SARS Coronavirus 2 and related subjects. We are extremely fortunate to have papers on the overarching issues of zoonotic spread (Gartner, Selleck) and how this relates to the practicalities of our responses via public health (Bennett), vaccination (Macintyre), antivirals (De Clercq), and immunotherapies (Kelleher). Diagnosis and transmission control have been at the centre of public health responses (Blackall, Speers), as has been research informing our understanding of the virus (Dhakal, Zaunders, Eden). A focus on basic research, translated into outcomes in real time, has been a very successful feature of the COVID-19 pandemic. We are privileged to be able to feature some of this research, in these papers, although this is only part of the extensive and excellent Australian work in reducing the impact of SARS CoV2 infection, and COVID-19 disease.
Social self-efficacy and sexual communication among adolescents in the United States: a cross-sectional study
Authors: Brasileiro Julia , Widman Laura , Evans Reina , Javidi Hannah
Published: April 2021

Background Sexual communication between partners is associated with safer sex behaviours, including condom use among adolescents. Several studies have found a relationship between negative psychological constructs (e.g. depression, anxiety) and poor sexual communication; however, scant research exists regarding positive psychological constructs and their potential to promote effective sexual communication among adolescents. This study examined the association between a positive construct, social self-efficacy – a person’s belief in their ability to successfully manage social relationships – and three components of sexual communication: sexual assertiveness, self-efficacy for communication, and frequency of sexual communication with dating partners. Methods: Data were collected in a cross-sectional survey from 222 high school girls in a rural school district in the south-eastern United States (Mage = 15.2; 38% White, 29% Latina, 24% Black; 50% were in a dating relationship in the past 3 months). Variables were measured with Likert-type scales. Bivariate correlation and regression analyses were conducted. Results: Social self-efficacy was significantly positively associated with sexual assertiveness and sexual communication self-efficacy for all girls, and there was a positive trend in the relationship between social self-efficacy and communication frequency among the subsample of girls who had a dating partner. The significant relationship with sexual assertiveness (β = 0.22, s.e. = 0.07, P = 0.001) and sexual communication self-efficacy (β = 0.17, s.e. = 0.04, P = 0.013) remained when controlling for sexual activity status. Conclusions: Strengthening social self-efficacy may enhance girls’ sexual communication and assertiveness skills. Future studies are needed to confirm the causal and temporal nature of these associations.
Planococcus citri (citrus mealybug).
Authors: Watson Gillian
Published: April 2021

Planococcus citri is a highly polyphagous, adaptable mealybug that can feed on many host plants in a variety of conditions, and can reproduce rapidly. It has been reported on over 200 host-plant species belonging to 191 genera and 82 families, and can seriously damage many crops, particularly citrus and glasshouse tomatoes. It is known to transmit some plant virus diseases like Cacao swollen shoot virus. The mealybug is of Old World origin, but its polyphagy has facilitated its spread about the world by human transport of infested plants over many years, and it is now established in in all the temperate and tropical zoogeographic regions, and lives under glass in higher latitudes. Its small size and cryptic habits makes it difficult to detect and identify at plant quarantine inspection. The increase in international trade in fresh plant material in recent years is facilitating its continued spread.
Anastrepha serpentina (sapodilla fruit fly).
Authors: Norrbom Allen
Published: April 2021

A. serpentina is a pest of various cultivated species of Sapotaceae, especially caimito [Chrysophyllum cainito], sapodilla [Manilkara zapota], and sapote [Capparis angulata], and it occasionally attacks a variety of other hosts, including Citrus spp. It is a widespread species in the American tropics, occurring from Mexico to Argentina. It has been intercepted and trapped in the USA (Florida, California) and other countries outside its range indicating its potential for spread via infested fruits.
Unified description of galactic dynamics and the cosmological constant
Authors: Cadoni Mariano , Sanna Andrea P
Published: April 2021

We explore the phenomenology of a two-fluid cosmological model, where the field equations of general relativity are sourced by baryonic and cold dark matter. We find that the model allows for a unified description of small and large scale, late-time cosmological dynamics. Specifically, in the static regime we recover the flattening of galactic rotation curves by requiring the matter density profile to scale as 1/r
2. The same behavior describes matter inhomogeneities distribution at small cosmological scales. This traces galactic dynamics back to structure formation. At large cosmological scales, we focus on back reaction effects of the spacetime geometry to the presence of matter inhomogeneities. We find that a cosmological constant (CC) with the observed order of magnitude, emerges by averaging the back reaction term on spatial scales of order 100 Mpc and it is related in a natural way to matter distribution. This provides a resolution to both the CC and the coincidence problems and shows the existence of an intriguing link between the small and large scale behavior in cosmology.
Low loss and omnidirectional Si3N4 waveguide for label-free spatial frequency shift super-resolution imaging
Authors: Ye Dehao , Tang Mingwei , Liu Xiaowei , Ma Yaoguang , Liu Xu , Yang Qing
Published: April 2021

Waveguide-based spatial frequency shift (SFS) super-resolution imaging has attracted growing interest for its high integration, low cost and compatibility with integrated circuit processes. However, a missing band in the spatial frequency (SF) domain severely impedes the final distortionless super-resolution image reconstruction. Here, we present a tunable multi-wavelength SFS method that can light the sample with tunable wavelength illuminations in a sequence using multiple directions of waveguide illumination. The SFS scheme provides broad and complete spectrum information, enabling a reconstructed super-resolution image with high fidelity. An etched three-slot structure and randomly distributed polymer beads on the waveguide surface are imaged and reconstructed with a Gerchberg–Saxton (G-S) SF synthesis algorithm. To the best of our knowledge, this is the first report that shows the waveguide-based label-free super-resolution imaging capability of complex random samples. In the future, the novel SFS imaging waveguide can potentially be integrated with conventional microscopes for chip-based label-free super-resolution imaging.
New frontiers in extreme conditions science at synchrotrons and free electron lasers
Authors: Cerantola Valerio , Rosa Angelika Dorothea , Konôpková Zuzana , Torchio Raffaella , Brambrink Erik , Rack Alexander , Zastrau Ulf , Pascarelli Sakura
Published: April 2021

Synchrotrons and free electron lasers are unique facilities to probe the atomic structure and electronic properties of matter at extreme thermodynamical conditions. In this context, ‘matter at extreme pressures and temperatures’ was one of the science drivers for the construction of low emittance 4th generation synchrotron sources such as the Extremely Brilliant Source of the European Synchrotron Radiation Facility and hard x-ray free electron lasers, such as the European x-ray free electron laser. These new user facilities combine static high pressure and dynamic shock compression experiments to outstanding high brilliance and submicron beams. This combination not only increases the data-quality but also enlarges tremendously the accessible pressure, temperature and density space. At the same time, the large spectrum of available complementary x-ray diagnostics for static and shock compression studies opens unprecedented insights into the state of matter at extremes. The article aims at highlighting a new horizon of scientific opportunities based on the synergy between extremely brilliant synchrotrons and hard x-ray free electron lasers.
Analysis of different asymmetries in B → K
*
ℓ
+
ℓ
− in 2D and 1D Scenarios
Authors: Shafaq Saba , Ahmad Ishtiaq , Bano Rawish , Javaid Nida , Nasrullah Aqsa , Barakat Thabit
Published: April 2021

At present experimental study, B meson decays, show some deviations from it’s SM predictions of certain physical observables, the focus of this study is to investigate the causes of these deviations. The effects are thus first studied by introducing the chirality flipped operators (not present in SM) and by giving non zero values to at least two different Wilson Coefficients. Then for

C

9

NP

=
−

C

10

NP

condition effects has been studied using the couplings of LQ and

Z

′

models. A general comprehensive expression for different observables in terms of WC’s is given for both the scenarios, and the simultaneous plots of different observables are also presented which can help us to narrow down the range of NP parameters for future studies.
Application of Natural Language Processing Technology in Educational Resources Retrieval
Authors: Huang Yibao
Published: April 2021

According to the data structure characteristics of educational resources, natural language processing technology is used to process the original educational resources data from the aspects of word segmentation processing, named entity recognition, part of speech tagging, synonym analysis, word vector analysis, etc. For complex image data, OCR preprocessing and coding format conversion are used to reduce the complexity of the original data; according to the difficulty requirements of the user to retrieve data, key words or ontology are selected to further expand and enrich the semantics and improve the accuracy of the retrieval results.
Problems and Countermeasures for the Data Mining of Medical Records of Traditional Chinese Medicine in the Era of Big Data
Authors: Wang Xiaofang , Hu Xiaojie , Liu Cheng
Published: April 2021

The medical records of Traditional Chinese Medicine (TCM) such as Huangdi’s Canon of Medicine and Treatise on Typhoid and Miscellaneous Diseases have always been the hot research objects in the field of TCM. Many papers on the summary and statistical analysis of TCM medical records have appeared one after another, which has played a huge role in promoting the development of TCM. However, with the progress of the times, the research of Traditional Chinese Medicine should keep pace with the new times. The authors in this paper introduced the research status and role of the data mining technology and mining methods, the problems and countermeasures of data mining technology in the research of Traditional Chinese Medicine medical records at this stage.
Application of Science and Technology Project Learning in English Linguistics Teaching with Integration of Machine Learning
Authors: Liu Tianning
Published: April 2021

Linguistics is a compulsory course for college English majors. The purpose of setting up linguistics is to cultivate students’ English language awareness, improve their comprehension of English language, and jump out of the Chinese-English language circle. Project learning came into being under this trend. It is student-centered and focuses on improving students’ desire for learning. It also differs from the past in teaching mode. Project learning allows students to pass through a relatively free space. Questions to stimulate students’ desire to explore, so as to trace the source of the entire problem, such links are discovered by students’ cooperation is essential. They are not teachers and professors. This can improve students’ learning efficiency, increase their understanding of English language, and increase their confidence in learning English linguistics. Therefore, this paper discusses the application of science and technology project learning in English linguistics teaching with integration of machine learning. In our designed model, the neural networks and the PCA are integrated to present the proper combination. The experimental performance is validated through the public databases and the proposed model outperforms compared with the other state-of-the-art methodologies.
Self-supervised Dense Depth Prediction in Monocular Endoscope Video for 3D Liver Surface Reconstruction
Authors: Cao Zhengtao , Huang Wenfeng , Liao Xiangyun , Deng Xuesong , Wang Qiong
Published: April 2021

In this paper, we propose a self-supervised monocular depth prediction method which combines traditional multi-view stereo method and fully convolutional network to predict the depth map in monocular endoscopic video and achieve 3D dense reconstruction of liver surface. We adopt the sparse data generated by COLMAP supervision signal as the training data, and integrate the attention model in the fully convolutional network to effectively extract the channel features to improve the accuracy of depth prediction. Taking into account the problem of insufficient supervision ability of sparse data, the projection transformation of two images within a certain range is carried out to make up for the missing supervision points. Experimental results show that this method has achieved good results in the depth prediction of monocular endoscopic video and has good applicability to the whole liver.
Traffic data prediction of mobile communication base station based on wavelet neural network
Authors: Lei Ming , Qin Rui , Mao Wentao , Lu Hongxia
Published: April 2021

With the wide application of new media, users require more and more mobile communication. In order to satisfy users’ high-quality experience and save resources, it is necessary to predict the traffic data of mobile communication base station, so that mobile communication base station can adjust the frequency load quantity according to the traffic fluctuation. From March 1 to April 9, 2018, this paper collects traffic data, selects 40, 000 sets of data, uses python to mine data, and predicts the traffic data of mobile communication base station by establishing wavelet neural network short-time traffic prediction model. The results show that the average accuracy of the short-term prediction model is 43. 15 and the root mean square error is 0. 0076.
The Reconstruction of Accounting Information Disclosure System Based on Blockchain Technology
Authors: Chen Yuxue , Chen Zihong , Hu Die
Published: April 2021

In recent years, the trust relationship of financial reports in the capital market has been severely challenged. The reliability, relevance and timeliness of the accounting information provided by the company’s financial reports are obviously insufficient, and the efficiency of capital market accounting supervision has been greatly reduced. In the digital economy era, traditional double-entry accounting and financial accounting reports are no longer sufficient to serve the new economy, and it is imperative to reconstruct the accounting information disclosure system. This article attempts to implement the nine-character policy of capital market reform. Firstly, to reconstruct the accounting information disclosure system based on blockchain technology; and under the background of the system with less government intervention, various entities Automatically realize the maintenance of distributed ledger and the disclosure of financial accounting information, based on the principle of self-interest. Finally, in addition to legal restrictions, it is more difficult for untrustworthy persons to participate in the maintenance of distributed ledger, in order to increase their economic costs and achieve zero tolerance for them.
An Efficient OpenCL-Based FPGA Accelerator for MobileNet
Authors: Wei Liu , Peng Lv
Published: April 2021

Convolutional neural network is widely used in image processing and image recognition. In order to obtain higher accuracy, the computational complexity and the scale of model and parameters are increasing. FPGA has become a good choice because of its low power consumption and high flexibility. MobileNet replaces the standard convolution by depthwise convolution and pointwise convolution, which greatly reduces the computational complexity and parameters of the model in the case of less precision loss, so that it can be applied to the equipment with limited computing resources. In this paper, we propose an efficient OpenCL-based FPGA CNN accelerator to realize inferencing acceleration of MobileNet. We designed the convolution layer with modularization. We used pipeline to design a depth separable convolution parallel acceleration scheme, and made full use of the DSP resources of FPGA. This design finally achieved a good balance of hardware resources, processing speed and power consumption. The experiments show that the accelerator can reach the inferencing speed of 32.56ms, and the energy consumption is 20W. The speedup is 4x compared with CPU and energy efficiency is 3x compared with GPU.
Research on Network Security Situation Assessment Technology Based on Fuzzy Evaluation Method
Authors: Kong Dehua , li Huyuan , dong Hongyan
Published: April 2021

With the development of Internet technology and the continuous improvement of social informatization, the network has gradually become an indispensable part of people’s production and life. The importance of network security has received more and more attention. A variety of security products have been applied to the network to strengthen and maintain the safe operation of the network. However, these security means can only play a specific role in a certain range, and lack of effective data fusion and collaborative management mechanism. In the face of many scattered information, network security managers cannot respond to security incidents in time. For the purpose of grasping the current situation and changes of network security, network security situation awareness technology came into being, it has become a new hotspot in network security research. This paper proposes a fuzzy comprehensive evaluation model which combines AHP and fuzzy evaluation method to evaluate network security situation.
An improved dynamic window approach for local trajectory planning in the environment with dense objects
Authors: Mai Xiquan , Li Di , Ouyang Jian , Luo Yongchao
Published: April 2021

The Dynamic Window Approach (DWA) has been one of the most popular solutions in local trajectory planning due to the advantages of movement fluency. However, the traditional DWA faces the challenge of low-efficiency in the case of local trajectory planning since the robot cannot perceive the density of the obstacle. In this paper, we propose an improved DWA to solve this problem. First, we use multi-sensor technology and new evaluation algorithms to enable the capability of density perception for the disorderly environment. Second, the evaluation factor related to the density change is introduced into the path evaluation function, which will facilitate the robot to perceive the distribution of dense objects in advance. Computer simulation and field experiments show that the efficiency of the improved DWA is increased by 25%. The improved DWA not only considers the original factors such as heading angle, but also introduces a density factor to evaluate the next path, so as to avoid entering dense areas in advance. It can be seen that the improved DWA has relatively stable speed and acceleration, and can avoid dense areas in advance, which can be widely used in robots running in dense environments.
Research on a lift car collision avoidance strategy for a circulatory multipath elevator based on digital twins
Authors: Chen Jiwen , Wang Lei , Li Xin , Yang Hongjuan , Yang Rui
Published: April 2021

To reduce the lateral movement time of elevator passengers in large-span high-rise buildings, a circulatory multipath elevator design scheme is proposed. To reduce the complexity of the circulatory multipath elevator control process due to the increase in the number of lift cars, a circulatory multipath elevator control system framework is established based on digital twin technology. To ensure the safe operation of the elevator, a lift car following model is established, and a circulatory multipath elevator collision avoidance strategy is designed. The lift car collision avoidance strategy can effectively reduce collision accidents in the process of multi lift car operation and ensure the safety of elevator passengers.
Simulations of the COVID-19 Epidemic in Nigeria Using SIR Model
Authors: Duan Yimeng
Published: April 2021

This study aims to review some applications of SIR model in COVID-19 epidemic situations, and tries to simulate the predictions of COVID-19 epidemic in a specific country using SIR model and R coding. This article picks Nigeria as the example, applying data from 28 February to 31 May and simulating the infected cases with Coronavirus. Based on literature review about usage of SIR model in this epidemic, the current trend is focusing on the optimization of parameters and algorithm. As a consequence, this study specifically initializes the SIR model with certain parameters and optimizes it through Maximum Likelihood Estimation using the Nelder-Mead algorithm. As the results show, the epidemic peak of Coronavirus cases in Nigeria is predicted to be reached around 20 May 2020, yet the peak has not been reached in reality and the growing rate is also quite different from the predicted curve. This phenomenon is considered as a consequence of a combined action and multiple factors that might attribute to it are discussed.
More than a nuisance: measuring how sea level rise delays commuters in Miami, FL
Authors: Hauer Mathew , Mueller Valerie , Sheriff Glenn , Zhong Qing
Published: April 2021

Sea level rise increases coastal cities’ exposure to tidal flooding and elevates the risk of transportation routes being compromised at high tide. Using Miami, Florida as a case study, we combine tide gauge, elevation, road network, and worker location data with a route optimization algorithm to model how tidal flooding affected commute times between 2002–2004 and 2015–2017. Results suggest tidal flooding increases annual commutes by 15 min on average and 274 min among the most heavily impacted areas. Additionally, approximately 14 000 commuters may be unable to reach their workplace due to tidal flooding at least once per year. Accommodation via dynamic adjustments in residential and work locations may reduce tidal commuting delays by as much as 70%, particularly among the highest earners. Many of the most affected areas do not experience flooding directly, expanding the purview of vulnerability beyond simple residential risk. Using 2060 extreme sea-level rise scenarios without accommodating behavior, mean annual commute delays are expected to reach 220 min with over 55 000 commuters potentially unable to reach their destinations.
O8: DIRECT MANIPULATION OF THE INTESTINAL MICROBIOME TO INFLUENCE POST-OPERATIVE OUTCOMES
Authors: Dilke SM , Durant LR , Stentz R , Wilson A , Tozer PJ , Vaizey CJ , Hoyles L , Carding S , Knight SC , Noble A
Published: April 2021

Introduction

Distal feeding (DF) involves intubation of the distal limb of a loop ileostomy to feed with a prebiotic mix. Studies suggest that distally feeding patients following anterior resection prior to ileostomy closure may be beneficial as a form of bowel pre-habilitation. These pilot data examine the adaptive immune response to DF.

Method

Ten healthy controls with an intact GI tract were compared with 10 patients following rectal cancer resection and chemo/radiotherapy, prior to closure of ileostomy over 8 weeks of DF. We examined B and T cell memory responses from peripheral blood using cell proliferation assays. Cells were cultured with dead antigen to reflect the microbiota in the small and large bowel. Two negative and two positive controls were used to assess minimal and maximum cell proliferation.

Result

B cell responses prior to DF were increased in the defunctioned group compared to the normal controls to significance (p=0.0014). After 8 weeks of DF the groups were comparable. T cell responses to bacteria had significant differences in proliferation rate following DF commencement, CD4 week 0 vs 3 p=0.0001, week 3 vs 8 p=0.000034, CD8 week 0 vs 3 p=0.0001, week 3-8 p=0.00024). In individual patients, CD4 responses were shown to shift from responses to facultative aerobic species, to strict anaerobes.

Conclusion

These data suggest that distal feeding fundamentally resets peripheral circulating memory and it may be of use in pre-habilitating the bowel prior to restoration of continuity. Early clinical data suggests that distal feeding improves post-operative outcomes.

Take-home message

distal feeding is an easy pre-operative intervention that has a significant effect on cell proliferation and antigen response, which may contribute to improved post operative outcomes.
Adults Hospitalized With Coronavirus Disease 2019 (COVID-19)—United States, March–June and October–December 2020: Implications for the Potential Effects of COVID-19 Tier-1 Vaccination on Future Hospitalizations and Outcomes
Authors: Sami Samira , Tenforde Mark W , Talbot H Keipp , Lindsell Christopher J , Steingrub Jay S , Shapiro Nathan I , Ginde Adit A , Douin David J , Prekker Matthew E , Erickson Heidi L , Brown Samuel M , Peltan Ithan D , Gong Michelle N , Khan Akram , Exline Matthew C , Files D Clark , Gibbs Kevin W , Rice Todd W , Casey Jonathan D , Grijalva Carlos G , Stubblefield William B , Womack Kelsey N , Hager David N , Qadir Nida , Chang Steven Y , Henning Daniel J , Wilson Jennifer G , Self Wesley H , Patel Manish M
Published: April 2021

Background

Because of the increased risk for severe coronavirus disease 2019 (COVID-19), the Advisory Committee on Immunization Practices (ACIP) initially prioritized COVID-19 vaccination for persons in long-term care facilities (LTCF), persons aged ≥65 years, and persons aged 16–64 years with high-risk medical conditions when there is limited vaccine supply. We compared characteristics and severe outcomes of hospitalized patients with COVID-19 in the United States between early and later in the pandemic categorized by groups at higher risk of severe COVID-19.

Methods

Observational study of sampled patients aged ≥18 years who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and admitted to one of 14 academic hospitals in the United States during March–June and October–December 2020. Demographic and clinical information were gathered from electronic health record data.

Results

Among 647 patients, 91% met ≥1 of the following risk factors for severe COVID-19 [91% March-June (n = 434); 90% October–December (n = 213)]; 19% were LTCF residents, 45% were aged ≥65-years, and 84% had ≥1 high-risk condition. The proportion of patients who resided in a LTCF declined significantly (25% vs 6%) from early to later pandemic periods. Compared with patients at lower risk for severe COVID-19, in-hospital mortality was higher among patients at high risk for severe COVID-19 (20% vs 7%); these differences were consistently observed between March–June and October–December.

Conclusions

Most adults hospitalized with COVID-19 were those recommended to be prioritized for vaccination based on risk for developing severe COVID-19. These findings highlight the continued urgency to vaccinate patients at high risk for severe COVID-19 and monitor vaccination impact on hospitalizations and outcomes.
Retrospective Detection of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) in Symptomatic Patients Prior to Widespread Diagnostic Testing in Southern California
Authors: Hilt Evann E , Boocock James , Trejo Marisol , Le Catherine Q , Guo Longhua , Zhang Yi , Sathe Laila , Arboleda Valerie A , Yin Yi , Bloom Joshua S , Wang Pin-Chieh , Elmore Joann G , Kruglyak Leonid , Shrestha Lasata , Bakhash Shah A Mohamed , Lin Michelle , Xie Hong , Huang Meei-Li , Roychoudhury Pavitra , Greninger Alexander , Chandrasekaran Sukantha , Yang Shangxin , Garner Omai B
Published: April 2021

Background

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused one of the worst pandemics in recent history. Few reports have revealed that SARS-CoV-2 was spreading in the United States as early as the end of January. In this study, we aimed to determine if SARS-CoV-2 had been circulating in the Los Angeles (LA) area at a time when access to diagnostic testing for coronavirus disease 2019 (COVID-19) was severely limited.

Methods

We used a pooling strategy to look for SARS-CoV-2 in remnant respiratory samples submitted for regular respiratory pathogen testing from symptomatic patients from November 2019 to early March 2020. We then performed sequencing on the positive samples.

Results

We detected SARS-CoV-2 in 7 specimens from 6 patients, dating back to mid-January. The earliest positive patient, with a sample collected on January 13, 2020 had no relevant travel history but did have a sibling with similar symptoms. Sequencing of these SARS-CoV-2 genomes revealed that the virus was introduced into the LA area from both domestic and international sources as early as January.

Conclusions

We present strong evidence of community spread of SARS-CoV-2 in the LA area well before widespread diagnostic testing was being performed in early 2020. These genomic data demonstrate that SARS-CoV-2 was being introduced into Los Angeles County from both international and domestic sources in January 2020.
Diagnostic Validation of a High-Sensitivity Cardiac Troponin I Assay
Authors: Sörensen Nils A , Goßling Alina , Neumann Johannes T , Hartikainen Tau S , Haller Paul M , Scharlemann Lea , Lehmacher Jonas , Ziegler Andreas , Blankenberg Stefan , Zeller Tanja , Nordholt Gerhard , Renné Thomas , Westermann Dirk
Published: April 2021

Background

Emergency departments worldwide are increasingly adopting rapid diagnosis of patients with suspected myocardial infarction (MI) based on high-sensitivity troponin. We set out to assess the diagnostic accuracy of a high-sensitivity cardiac troponin I (hs-cTnI) assay in a prospective study.

Methods

In a cohort study including 1800 patients presenting with suspected acute MI, we developed and temporally validated a 0/1 h diagnostic algorithm using the Siemens Atellica IM hs-cTnI assay. The algorithm was established in the first 928 patients and validated in the following 872 patients.

Results

The derived algorithm consisted of a baseline rule-out of non–ST-segment elevation MI using a cutoff <3 ng/L in patients with symptom onset ≥3 h or an admission troponin I level <6 ng/L with a Δ change of <3 ng/L from 0 h to 1 h. For rule-in, an admission troponin I level ≥120 ng/L or an increase within the first hour ≥12 ng/L was required. Application of the algorithm to the validation cohort showed a negative predictive value of 99.8% (95% CI, 98.7%–100.0%), sensitivity of 99.1% (95% CI, 95.1%–100.0%), and 48.3% of patients ruled out, whereas 15.1% were ruled in with a positive predictive value of 68.0% (95% CI, 59.1%–75.9%) and specificity of 94.4% (95% CI, 92.5%–96.0%). The diagnostic performance was comparable to guideline-recommended application of an established hs-cTnI assay in a rapid 0/1 h strategy.

Conclusions

The Siemens hs-cTnI assay is well suited for application in rapid diagnostic stratification of patients with suspected MI.

Study Registration

www.clinicaltrials.gov (NCT02355457)
The role of autophagy in cardiovascular pathology
Authors: Gatica Damián , Chiong Mario , Lavandero Sergio , Klionsky Daniel J
Published: April 2021

Macroautophagy/autophagy is a conserved catabolic recycling pathway in which cytoplasmic components are sequestered, degraded, and recycled to survive various stress conditions. Autophagy dysregulation has been observed and linked with the development and progression of several pathologies, including cardiovascular diseases, the leading cause of death in the developed world. In this review, we aim to provide a broad understanding of the different molecular factors that govern autophagy regulation and how these mechanisms are involved in the development of specific cardiovascular pathologies, including ischemic and reperfusion injury, myocardial infarction, cardiac hypertrophy, cardiac remodelling, and heart failure.
Prognostic implications of left ventricular myocardial work index in patients with ST-segment elevation myocardial infarction and reduced left ventricular ejection fraction
Authors: Butcher Steele C , Lustosa Rodolfo P , Abou Rachid , Marsan Nina Ajmone , Bax Jeroen J , Delgado Victoria
Published: April 2021

Aims

This study aimed to determine whether lower values of left ventricular (LV) global work index (GWI) at baseline were associated with a reduction in LV functional recovery and poorer long-term prognosis in patients with reduced LV ejection fraction (LVEF ≤40%) following ST-segment elevation myocardial infarction (STEMI).

Methods and results

A total of 197 individuals (62 ± 12 years, 75% male) with STEMI treated with primary percutaneous coronary intervention and reduced LVEF were evaluated. All patients were followed up for the occurrence of all-cause mortality and the presence of LVEF normalization at 6 months (LVEF ≥50%). The median LVEF was 36% (interquartile range 32–38) and the mean value of LV GWI was 1041 ± 404 mmHg% at baseline. At 6-month follow-up, 41% of patients had normalized LVEF. On multivariable logistic regression, higher values of LV GWI were independently associated with LVEF normalization at 6 months of follow-up (odds ratio 1.32 per 250 mmHg%, P = 0.038). Over a median follow-up of 112 months, 40 patients (20%) died. LV GWI <750 mmHg% was independently associated with all-cause mortality (HR 3.85, P < 0.001) and was incremental to LV global longitudinal strain (P = 0.039) and LVEF (P < 0.001).

Conclusion

In individuals with an LVEF ≤40% following STEMI, higher values of LV GWI were associated with a greater probability of LVEF normalization at 6-month follow-up. In addition, lower values of LV GWI were independently associated with increased all-cause mortality at long-term follow-up, providing incremental prognostic value over LVEF and minor incremental prognostic value over LV global longitudinal strain.
Sex differences on new-onset heart failure in patients with known or suspected coronary artery disease
Authors: Núñez Julio , Lorenzo Miguel , Miñana Gema , Palau Patricia , Monmeneu Jose V , López-Lereu Maria P , Gavara Jose , Marcos-Garcés Victor , Ríos-Navarro Cesar , Pérez Nerea , de Dios Elena , Núñez Eduardo , Sanchis Juan , Chorro Francisco J , Bayés-Genís Antoni , Bodí Vicent
Published: April 2021

Aims

The impact of sex in patients with CAD has been widely reported, but little is known about the influence of sex on the risk of new-onset HF in patients with known or suspected CAD. We aimed to examine sex-related differences and new-onset heart failure (HF) risk in patients with known or suspected coronary artery disease (CAD) undergoing vasodilator stress cardiac magnetic resonance (CMR).

Methods and results

We prospectively evaluated 5899 consecutive HF-free patients submitted to stress CMR for known or suspected CAD. Ischaemic burden (number of segments with stress-induced perfusion deficit) and left ventricular ejection fraction (LVEF) were assessed by CMR. The association between sex and new-onset HF (including outpatient diagnosis or acute HF hospitalization) was evaluated using a Cox proportional hazards regression model adjusted for competing events [death, myocardial infarction (MI), and revascularization]. A total of 2289 (38.8%) patients were women. During a median follow-up of 4.5 years, 610 (10.3%) patients died, 191 (3.2%) suffered an MI, 905 (15.3%) underwent revascularization, and 314 (5.3%) developed new-onset HF. Unadjusted new-onset HF rates were higher in women than in men (1.25 vs. 0.83 per 100 person-years, P = 0.001). After comprehensive multivariate adjustment, women showed an increased risk of new-onset HF (hazard ratio 1.58, 95% confidence interval 1.18–2.10; P = 0.002). We found a sex-differential effect along the continuum of LVEF (P-value for interaction = 0.007). At lower LVEF, there was an increased risk in both sexes. However, compared with men, the risk of new-onset HF was higher in women with LVEF >55%.

Conclusion

Women with known or suspected CAD are at a higher risk of new-onset HF. Further studies are needed to unravel the mechanisms behind these sex-related differences.
Prediction, enrichment and isolation identify a responsive, competitive community of cellulolytic microorganisms from a municipal landfill
Authors: Co Rebecca , Hug Laura A
Published: April 2021

Landfills are engineered, heterogeneously contaminated sites containing large reservoirs of paper waste. Cellulose degradation is an important process within landfill microbial ecology, and these anoxic, saturated environments are prime locations for discovery of cellulases that may offer improvements on industrial cellulose degradation efforts. We sampled leachate from three locations within a municipal landfill, a leachate collection cistern, and groundwater from an adjacent aquifer to identify cellulolytic populations and their associated cellulases. Metagenomic sequencing identified wide-spread and taxonomically diverse cellulolytic potential, with a notable scarcity of predicted exocellulases. 16S rRNA amplicon sequencing detected nine landfill microorganisms enriched in a customized leachate medium amended with microcrystalline cellulose or common paper stocks. Paper-enrichment cultures showed competition dynamics in response to the specific composition (lignin: hemi-cellulose: cellulose) of the different paper stocks. From leachate biomass, four novel cellulolytic bacteria were isolated, including two with the capacity for cellulolysis at industrially relevant temperatures. None of the isolates demonstrated exocellulase activity, consistent with the metagenome-based predictions. However, there was very little overlap between metagenome-derived predicted cellulolytic organisms, organisms enriched on paper sources, or the isolates, suggesting the landfill cellulolytic community is at low abundance but able to rapidly respond to introduced substrates.
Characterization of the Aspergillus nidulans Septin (asp) Gene Family
Authors: Momany Michelle , Zhao Jiong , Lindsey Rebecca , Westfall Patrick J
Published: April 2021

Members of the septin gene family are involved in cytokinesis and the organization of new growth in organisms as diverse as yeast, fruit fly, worm, mouse, and human. Five septin genes have been cloned and sequenced from the model filamentous fungus A. nidulans. As expected, the A. nidulans septins contain the highly conserved GTP binding and coiled-coil domains seen in other septins. On the basis of hybridization of clones to a chromosome-specific library and correlation with an A. nidulans physical map, the septins are not clustered but are scattered throughout the genome. In phylogenetic analysis most fungal septins could be grouped with one of the prototypical S. cerevisiae septins, Cdc3, Cdc10, Cdc11, and Cdc12. Intron-exon structure was conserved within septin classes. The results of this study suggest that most fungal septins belong to one of four orthologous classes.
Selective Sweeps in the Presence of Interference Among Partially Linked Loci
Authors: Kim Yuseob , Stephan Wolfgang
Published: April 2021

Recurrent directional selection on a partially recombining chromosome may cause a substantial reduction of standing genetic variation in natural populations. Previous studies of this effect, commonly called selective sweeps, assumed that at most one beneficial allele is on the way to fixation at a given time. However, for a high rate of selected substitutions and a low recombination rate, this assumption can easily be violated. We investigated this problem using full-forward simulations and analytical approximations. We found that interference between linked beneficial alleles causes a reduction of their fixation probabilities. The hitchhiking effect on linked neutral variation for a given substitution also slightly decreases due to interference. As a result, the strength of recurrent selective sweeps is weakened. However, this effect is significant only in chromosomal regions of relatively low recombination rates where the level of variation is greatly reduced. Therefore, previous results on recurrent selective sweeps although derived for a restricted parameter range are still valid. Analytical approximations are obtained for the case of complete linkage for which interference between competing beneficial alleles is maximal.
Phospholipase C-γ Contains Introns Shared by src Homology 2 Domains in Many Unrelated Proteins
Authors: Manning Charlene M , Mathews Wendy R , Fico Leah P , Thackeray Justin R
Published: April 2021

Many proteins with novel functions were created by exon shuffling around the time of the metazoan radiation. Phospholipase C-γ (PLC-γ) is typical of proteins that appeared at this time, containing several different modules that probably originated elsewhere. To gain insight into both PLC-γ evolution and structure-function relationships within the Drosophila PLC-γ encoded by small wing (sl), we cloned and sequenced the PLC-γ homologs from Drosophila pseudoobscura and D. virilis and compared their gene structure and predicted amino acid sequences with PLC-γ homologs in other animals. PLC-γ has been well conserved throughout, although structural differences suggest that the role of tyrosine phosphorylation in enzyme activation differs between vertebrates and invertebrates. Comparison of intron positions demonstrates that extensive intron loss has occurred during invertebrate evolution and also reveals the presence of conserved introns in both the N- and C-terminal PLC-γ SH2 domains that are present in SH2 domains in many other genes. These and other conserved SH2 introns suggest that the SH2 domains in PLC-γ are derived from an ancestral domain that was shuffled not only into PLC-γ, but also into many other unrelated genes during animal evolution.
A Large Rearrangement Involving Genes and Low-Copy DNA Interrupts the Microcollinearity Between Rice and Barley at the Rph7 Locus
Authors: Brunner S , Keller B , Feuillet C
Published: April 2021

Grass genomes differ greatly in chromosome number, ploidy level, and size. Despite these differences, very good conservation of the marker order (collinearity) was found at the genetic map level between the different grass genomes. Collinearity is particularly good between rice chromosome 1 and the group 3 chromosomes in the Triticeae. We have used this collinearity to saturate the leaf rust resistance locus Rph7 on chromosome 3HS in barley with ESTs originating from rice chromosome 1S. Chromosome walking allowed the establishment of a contig of 212 kb spanning the Rph7 resistance gene. Sequencing of the contig showed an average gene density of one gene/20 kb with islands of higher density. Comparison with the orthologous rice sequence revealed the complete conservation of five members of the HGA gene family whereas intergenic regions differ greatly in size and composition. In rice, the five genes are closely associated whereas in barley intergenic regions are >38-fold larger. The size difference is due mainly to the presence of six additional genes as well as noncoding low-copy sequences. Our data suggest that a major rearrangement occurred in this region since the Triticeae and rice lineage diverged.
Spectrum of Chemically Induced Mutations From a Large-Scale Reverse-Genetic Screen in Arabidopsis
Authors: Greene Elizabeth A , Codomo Christine A , Taylor Nicholas E , Henikoff Jorja G , Till Bradley J , Reynolds Steven H , Enns Linda C , Burtner Chris , Johnson Jessica E , Odden Anthony R , Comai Luca , Henikoff Steven
Published: April 2021

Chemical mutagenesis has been the workhorse of traditional genetics, but it has not been possible to determine underlying rates or distributions of mutations from phenotypic screens. However, reverse-genetic screens can be used to provide an unbiased ascertainment of mutation statistics. Here we report a comprehensive analysis of ∼1900 ethyl methanesulfonate (EMS)-induced mutations in 192 Arabidopsis thaliana target genes from a large-scale TILLING reverse-genetic project, about two orders of magnitude larger than previous such efforts. From this large data set, we are able to draw strong inferences about the occurrence and randomness of chemically induced mutations. We provide evidence that we have detected the large majority of mutations in the regions screened and confirm the robustness of the high-throughput TILLING method; therefore, any deviations from randomness can be attributed to selectional or mutational biases. Overall, we detect twice as many heterozygotes as homozygotes, as expected; however, for mutations that are predicted to truncate an encoded protein, we detect a ratio of 3.6:1, indicating selection against homozygous deleterious mutations. As expected for alkylation of guanine by EMS, >99% of mutations are G/C-to-A/T transitions. A nearest-neighbor bias around the mutated base pair suggests that mismatch repair counteracts alkylation damage.
Genetic Variability at Neutral Markers, Quantitative Trait Loci and Trait in a Subdivided Population Under Selection
Authors: Le Corre Valérie , Kremer Antoine
Published: April 2021

Genetic variability in a subdivided population under stabilizing and diversifying selection was investigated at three levels: neutral markers, QTL coding for a trait, and the trait itself. A quantitative model with additive effects was used to link genotypes to phenotypes. No physical linkage was introduced. Using an analytical approach, we compared the diversity within deme (HS) and the differentiation (FST) at the QTL with the genetic variance within deme (VW) and the differentiation (QST) for the trait. The difference between FST and QST was shown to depend on the relative amounts of covariance between QTL within and between demes. Simulations were used to study the effect of selection intensity, variance of optima among demes, and migration rate for an allogamous and predominantly selfing species. Contrasting dynamics of the genetic variability at markers, QTL, and trait were observed as a function of the level of gene flow and diversifying selection. The highest discrepancy among the three levels occurred under highly diversifying selection and high gene flow. Furthermore, diversifying selection might cause substantial heterogeneity among QTL, only a few of them showing allelic differentiation, while the others behave as neutral markers.