bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of the physicochemical qualities of groundwater and soils around oil-producing communities in Afam, area of Porthacourt, Niger Delta Nigeria
Authors: Igwe Ogbonnaya , Ngwoke Moses , Ukah Bernadette U. , Ubido Oyem E.
Published: April 2021

Results from the assessment of physicochemical qualities of groundwater and soils around Afam in Niger Delta done using, statistical model, geo-accumulation indices (I-geo) and water quality indices showed that pH and Cu did not correlate strongly with any of the parameters analyzed in the study area. At 2-tailed of 0.05 levels of significance, moderate correlation exist between dissolved oxygen and Ca > Na, strong to moderate correlation exist between temperature and total dissolved solids (TDS) > E.C > Na and Ca, whereas at 2-tailed level of 0.02, very strong correlation exist between E.C and TDS (0.988), > Na (0.966), > Ca (0.957). TDS in turn is strongly correlated with Na (0.987), > Ca (0.972). Fe, Zn, Pb and Cr, total petroleum hydrocarbon (TPHC), oil and grease (O&G) (< 0.001 mg/l) did not correlate with any of the physicochemical elements in the samples. At 2-tailed levels of 0.02 and 0.05, no significant correlation exists between alkalinity and salinity in groundwater samples and also with any the elements. Groundwater showed excellent water quality except one (62.307). pH, Cr, Fe, Ni, Pb and Cu in the soil were unpolluted since I-geo values are less than 1. Polycyclic aromatic hydrocarbon (PAH) (2.5194) showed low pollution, O&G (3.8886) showed moderate pollution, while total hydrocarbon content (THC) (6.2069), total organic carbon (TOC) (7.4919) and TPHC (9.4851) showed extreme pollution. The control site appeared to be unpolluted except TOC (6.8721). Percentage of clay particles in the soil is higher than in control.
Two-Vehicle Coordination System for Omnidirectional Transportation Based on Image Processing and Deviation Prediction
Authors: Song Huajun , Wu Yanqi , Wu Yuxing , Zhou Guangbing , Luo Chunbo
Published: April 2021

Omnidirectional mobile platform is essential due to its excellent mobility and versatility. With the development of the manufacturing industry, how to transport oversized or overweight goods has become a new problem. Compared with manufacturing omnidirectional mobile platforms with different specifications, it is more cost-effective and flexible to coordinate two non-physically connected omnidirectional platforms to transport overweight and oversized cargo. The roughness of the actual deployment environment and the mechanical deflection between the two vehicles have a significant impact on the normal operation of the system. This paper combines mechanical wheels, image processing algorithms and collaboration algorithms to create a novel and practical split-type omnidirectional mobile platform based on image deviation prediction for transporting oversized or overweighted goods. The proposed system collects raw measurements from a distance sensor and an image sensor, transmits them to a central processing unit through a wireless communication module and calculates and predicts the relative deflection between the two vehicles based on our derived mathematical model. This information is then fed to a Kalman filter and PID control algorithm to coordinate the two vehicles. The effectiveness and performance of our system have been thoroughly tested, which has already been applied in a bullet train production line.
First but not second postoperative day growth hormone assessments as early predictive tests for long-term acromegaly persistence
Authors: Cambria V. , Beccuti G. , Prencipe N. , Penner F. , Gasco V. , Gatti F. , Romanisio M. , Caputo M. , Ghigo E. , Zenga F. , Grottoli S.
Published: April 2021

Purpose

Postoperative assessment of acromegaly activity is typically performed at least 3 months after neurosurgery (NS). Few studies have evaluated the use of early postoperative growth hormone (GH) levels as a test to predict short- and long-term remission of acromegaly. Our objective was to evaluate the diagnostic performance of serum random GH on a postoperative day one (D1-rGH) and two (D2-rGH), particularly in predicting long-term disease persistence.

Materials and methods

Forty-one subjects with acromegaly who were undergoing NS were enrolled (mean age ± SD 47.4 ± 13.1 years at diagnosis; women 54%; macroadenomas 71%). The final assessment of disease activity was performed one year after NS. ROC curves were used to evaluate the diagnostic performance of D1-rGH and D2-rGH.

Results

After a 1-year follow-up, the overall remission rate was 55%. ROC analysis identified an optimal D1-rGH cut-off value of 2.1 ng/mL for diagnosing long-term disease persistence (55.6% SE; 90.9% SP). The cut-off point became 2.5 ng/mL after maximizing specificity for disease persistence (yielding a 100% positive predictive value) and 0.3 ng/mL after maximizing sensitivity for disease remission. The optimal D2-rGH cut-off value was 0.6 ng/mL (81.8% SE; 50% SP); the cut-off point became 2.9 ng/mL after maximizing specificity and 0.1 ng/mL after maximizing sensitivity, with no clinical utility.

Conclusions

D1-rGH could be a highly specific test for the early diagnosis of long-term acromegaly persistence, which is predicted by a value > 2.5 ng/mL with a great degree of certainty. The diagnostic performance of D2-rGH was insufficient. Further research is required to validate these preliminary results prior to modifying the postoperative management of acromegaly.
Modeling metallurgical responses of coal Tri-Flo separators by a novel BNN: a “Conscious-Lab” development
Authors: Alidokht Mehdi , Yazdani Samaneh , Hadavandi Esmaeil , Chehreh Chelgani Saeed
Published: April 2021

Tri-flo cyclone, as a dense-medium separation device, is one of the most typical environmentally friendly industrial techniques in the coal washery plants. Surprisingly, no detailed investigation has been conducted to explore the effectiveness of tri-flo cyclone operating parameters on their representative metallurgical responses (yield and recovery). To fill this gap, this work for the first time in the coal processing sector is going to introduce a type of advanced intelligent method (boosted-neural network “BNN”) which is able to linearly and nonlinearly assess multivariable correlations among all variables, rank them based on their effectiveness and model their produced responses. These assessments and modeling were considered a new concept called “Conscious Laboratory (CL)”. CL can markedly decrease the number of laboratory experiments, reduce cost, save time, remove scaling up risks, expand maintaining processes, and significantly improve our knowledge about the modeled system. In this study, a robust monitoring database from the Tabas coal plant was prepared to cover various conditions for building a CL for coal tri-flo separators. Well-known machine learning methods, random forest, and support vector regression were developed to validate BNN outcomes. The comparisons indicated the accuracy and strength of BNN over the examined traditional modeling methods. In a sentence, generating a novel BNN within the CL concept can apply in various energy and coal processing areas, fill gaps in our knowledge about possible interactions, and open a new window for plants' fully automotive process.
Evolution of Dynamical Complexities in Geospace as Captured by Dst Over Four Solar Cycles 1964–2008.
Authors: Ogunjo S. T. , Rabiu A. B. , Fuwape I. A. , Obafaye A. A.
Published: April 2021

The dynamical complexities of geospace has been examined by investigating the characteristic chaotic properties of hourly Dst values obtained from the World Data Center for Geomagnetism, Kyoto, over four solar cycles (1964–2008) using nonlinear methods: sample entropy, Lyapunov exponents, correlation dimension, recurrence quantification analysis, and multifractal detrended fluctuation. Throughout the solar cycles considered, the space environment was observed to be chaotic based on Lyapunov exponents obtained. The order of increasing complexity in the solar cycles based on recurrence rate (RR) values is Cycle 21 < 22 < 23 < 20. Similar patterns and trend were observed in the correlation dimension values for the different solar cycles. The peak of each solar cycle is associated with high chaoticity. In all the analysis considered, high values of sample entropy, Lyapunov exponent, correlation dimension, correspond to increasing chaoticity. However, lower value of RR signifies more chaotic activity. The solar cycle 20 with the greatest values of mean sunspot number (651.62) and standard deviation of sunspot number (1,656.90) has the greatest chaoticity. The chaoticity in the magnetosphere increases with increasing geomagnetic activity as captured by Dst index. Similar trends were not observed in BZ and solar wind dynamic pressure which showed that the observed chaoticity is due to internal variations. The multifractal spectrum of Dst at all solar cycles considered revealed that the chaotic activities in the magnetosphere are not influenced by the local fluctuations in the region. The degree of multifractality were found to be in the order Cycle 20 > Cycle 23 > Cycle 21 > Cycle 22.
The Signature and Elimination of Sediment Reverberations on Submarine Receiver Functions
Authors: Zhang Ziqi , Olugboji Tolulope
Published: April 2021

While the receiver function technique has been successfully applied to high‐resolution imaging of sharp discontinuities within and across the lithosphere, it suffers from severe limitations when applied to seafloor seismic recordings. This is because the water and sediment layer could strongly influence the receiver function traces, making detection and interpretation of crust and mantle layering difficult. This effect is often referred to as the singing phenomena in marine environments. We demonstrate, using analytical and synthetic modeling, that this singing effect can be reversed using a selective dereverberation filter tuned to match the elastic property of each layer. We apply the dereverberation filter to high‐quality earthquake records collected from the NoMelt seismic array deployed on normal, mature Pacific seafloor. An appropriate filter designed using the elastic properties of the underlying sediments, obtained from prior studies, greatly improves the detection of Ps conversions from the Moho (∼8.6 km) and from a sharp discontinuity (<∼5 km) across the lithosphere asthenosphere transition (∼72 km). Sensitivity tests show that the dereverberation filter is mostly sensitive to the two‐way travel time of the shear wave in sediment and is robust to seismic noise and small errors in the sediment properties. Our analysis suggests that selectively filtering out the sediment reverberations from ocean seismic data could make inferences on subsurface structure more robust. We expect that this study will enable high‐resolution receiver function imaging of the oceanic plate across the growing ocean bottom seismic arrays being deployed in the global oceans.
The Investigation of the Connections Among Hydrogeological Factors and the Emissions of Two Greenhouse Gases in Lake Sediment
Authors: Lu Xiang , Zhou Xiaotian , Xu Yaofei , Ruan Aidong , Yu Zhongbo
Published: April 2021

Wet ecosystems are important in terms of global greenhouse gas emissions, where a high soil water content is one of the most typical features. However, the roles of hydrogeological properties in sediment during the emission process of methane and carbon dioxide remain to be researched, especially in lake ecosystems. In this study, through investigating the layered sediment in Chaohu Lake, we discovered that strong correlations exist between the water content and microbial gas emissions (methane and carbon dioxide). To further examine these correlations, a systematic analysis of the hydrogeological properties in sediment, gas emission features, methane bubble emission theories and microbiomics was conducted. The results revealed that microbial methane emissions can influence sediment structure and the interstitial water content. Differently, the similar distributions in different layers probably lead to the correlations between microbial carbon dioxide emission and the water content. This research also discusses the connections with other hydrogeological parameters (particle features, interstitial space, etc.) during the emission process. In addition, this study addresses the significance of methane emissions for the material exchange between overlying water and sediment. The effect of microbial gas emissions on sediment physical‐chemical properties also provides meaningful information for researching the relationships among environmental factors and microbial ecology.
A Space Hurricane Spotted Above the Polar Cap
Authors: Wheeling Kate
Published: April 2021

Researchers have identified a high-latitude phenomenon that looks remarkably like a tropospheric hurricane, with spinning arms of plasma and a shower of electrons.
Repeating Earthquakes at the Edge of the Afterslip of the 2016 Ecuadorian MW7.8 Pedernales Earthquake
Authors: Chalumeau Caroline , Agurto‐Detzel Hans , De Barros Louis , Charvis Philippe , Galve Audrey , Rietbrock Andreas , Alvarado Alexandra , Hernandez Stephen , Beck Susan , Font Yvonne , Hoskins Mariah C. , León‐Ríos Sergio , Meltzer Anne , Lynner Colton , Rolandone Frederique , Nocquet Jean‐Mathieu , Régnier Marc , Ruiz Mario , Soto‐Cordero Lillian , Vaca Sandro , Segovia Mónica
Published: April 2021

Repeating earthquakes repeatedly rupture the same seismic asperity and are strongly linked to aseismic slip. Here, we study the repeating aftershocks of the April 16, 2016 MW 7.8 Pedernales earthquake in Ecuador, which generated a large amount of afterslip. Using temporary and permanent stations, we correlate waveforms from a one‐year catalog of aftershocks. We sort events with a minimum correlation coefficient of 0.95 into preliminary families, which are then expanded using template‐matching to include events from April 2015 to June 2017. In total, 376 repeaters are classified into 62 families of 4–15 events. They are relocated, first using manual picks, and then using a double difference method. We find repeating earthquakes during the whole period, occurring primarily within large aftershock clusters on the edges of the areas of largest afterslip release. Their recurrence times, shortened by the mainshock, subsequently increase following an Omori‐type law, providing a timeframe for the afterslip's deceleration. Although they are linked temporally to the afterslip, repeater‐derived estimates of slip differ significantly from GPS‐based models. Combined with the fact that repeaters appear more spatially correlated with the afterslip gradient than with the afterslip maxima, we suggest that stress accumulation at the edge of the afterslip may guide repeater behavior.
The stability of aerobic granular sludge under low energy consumption: optimization of the granular size distribution by a novel internal component
Authors: Cao Runjuan , Ji Yatong , Han Taixing , Deng Jingsong , Zhu Liang , Xu Xiangyang
Published: April 2021

An innovative and energy-saving reactor set-up can optimize the granule size distribution and achieve stable aerobic granular sludge.
Library construction of stereochemically diverse isomers of spirooliganin: their total synthesis and antiviral activity
Authors: Wang Ru-Bing , Ma Shuang-Gang , Jamieson Cooper S. , Gao Rong-Mei , Liu Yun-Bao , Li Yong , Wang Xiao-Jing , Li Yu-Huan , Houk Kendall N. , Qu Jing , Yu Shi-Shan
Published: April 2021

Library construction of stereochemically diverse isomers to investigate the relationship between stereoconfiguration and anti-coxsackie virus B3 activity.
An Efficient Strategy for the Synthesis of Naphtho[2,3-b][1,6]naphthyridines Promoted by Acetic Acid
Authors: Zhang Furen , Shen Zhenlu , Li Chunmei
Published: April 2021

A three-component domino reaction for the synthesis of naphtho[2,3-b][1,6]naphthyridine derivatives has been established. Such strategy exhibited excellent substrate scope including various enaminones and aldehydes that afforded a series of multifunctionalized naphtho[2,3-b][1,6]naphthyridine derivatives with 70–86% yields. The advantages of bond-forming efficiency, accessibility of starting materials, and water as sole byproducts provide invaluable access to biological 1,6-naphthyridines.
How I Do it: A Practical Database Management System to Assist Clinical Research Teams with Data Collection, Organization, and Reporting
Authors: Elsaadany Amr Maged , Alaeddin Fida Hasan , Badran Mohamed Farouk , Alsuhaibani Hamad Saleh
Published: April 2021

With the growing amount of research projects in the field of interventional radiology, storing and organizing the patients' data and information effectively is becoming more difficult. Existing hospital electronic medical record and archiving systems store patient information in the form of reports which put the physicians and researchers in a situation where they have to use time-consuming manual search through reports for suitable patients for different clinical researches. Spreadsheet programs such as Microsoft Excel® (Microsoft, Washington, USA) are often used as a data storage, which has limitations in both organization and the quality of the data. Higher risk of incorrect data entry and introducing duplicates are associated with data input and analysis without a database system. Furthermore, selection, as well as calculation of data, is time-consuming. This article aims to provide interventionists with an efficient data collection tool optimized for interventional oncology clinical research. The implementation of the current database and interface allows a much faster and more detailed retrospective analysis of patient cohorts. The database management system with an interface is a very time-efficient and robust tool that provides a significant edge over the manual retrieval of patient records by filtering data and assisting statistical analysis in a study-relevant fashion.
Percutaneous Removal of Gallstones Under Fluoroscopy Guidance in High-risk Patients with Acute Cholecystitis
Authors: Al Nammi Ahmed , Cheema Ahsan , Al Nammi Mohanned , Chaudhry Ikram
Published: April 2021

We report our technique of percutaneous removal of gallstones in three elderly patients with acute calculus cholecystitis who were not surgical candidates due to multiple comorbidities. The procedure is performed under local anesthesia using fluoroscopic and choledochoscopic guidance. All patients had uneventful recovery and were discharged home in 3–4 days and fallow up at a low and high surveillance by ultrasound at 3 and 6 months interval.
Chrysomyxa abietis (needle rust of fir).
Authors:   USA, USDA-ARS
Published: April 2021

C. abietis is a microcyclic rust fungus; an obligate parasite completing its life cycle on species of Picea (spruce). Only the current year's needles of Picea are infected and those needles are shed early. Reported from northern Europe and Asia, the fungus is a Regulated Pest for the USA. It is absent from North America, where susceptible species are native, and Australia and New Zealand, where they are introduced. Although usually not a significant problem in its native range, because conditions are not favourable for heavy infections every year (Smith et al., 1988; Hansen, 1997), this rust could be more damaging as an invasive in other temperate areas. Due to the fact that small amounts of infection may be overlooked, accidental introduction could occur through importation of infected seedlings or young trees.
Caesalpinia decapetala (Mysore thorn).
Authors: Rojas-Sandoval Julissa , Acevedo-Rodríguez Pedro
Published: April 2021

C. decapetala is an adaptable scrambling, very prickly shrub with showy sulfur-yellow flowers, and is very widely distributed in South and East Asia. This species grows naturally in tropical temperate regions from the Himalayas to Sri Lanka, and extends to China, Korea and Japan. C. decapetala forms dense thickets and hedges useful for pasture demarcation and boundaries, it is also used as a shade tree. The bark has tanning properties, while the seeds are locally important for medicinal uses including anthelminthic, antipyretic, analgesic and possibly contraceptive properties. This species is also used to treat dysentery, malaria and neuraligia. C. decapetala is easy to propagate by direct seeding, but has been reported to tend towards weediness in some situations in Africa and Australia.
Elaeagnus pungens (thorny olive).
Authors: Pasiecznik Nick
Published: April 2021

A datasheet on Elaeagnus pungens covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Euonymus japonicus (Japanese spindle tree).
Authors: Parker Chris , Acevedo-Rodríguez Pedro
Published: April 2021

A datasheet on Euonymus japonicus covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Funtumia elastica (West African rubber tree).
Authors: Vélez-Gavilán Jeanine
Published: April 2021

A datasheet on Funtumia elastica covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
Macaranga tanarius (parasol leaf tree).
Authors: Quiroz Diana
Published: April 2021

A datasheet on Macaranga tanarius covering, as an economically important tree, its taxonomy, importance, silviculture, distribution, biology and ecology, uses, products and pests.
SPDE: a multi-functional software for sequence processing and data extraction
Authors: Xu Dong , Lu Zhuchou , Jin Kangming , Qiu Wenmin , Qiao Guirong , Han Xiaojiao , Zhuo Renying
Published: April 2021

Sequence Processing and Data Extraction (SPDE) has eight modules comprising 100 basic functions ranging from sequence extraction, format conversion to data reorganization and mining, and all of these functions can be completed by point-and-click icons. SPDE also incorporates eight public analyses tools; thus, SPDE is a comprehensive bioinformatics platform for big biological data analysis.

Availability and implementation

SPDE built by Python can run on 32-bit, 64-bit Windows and MacOS systems. It can be downloaded from https://github.com/simon19891216/SPDEv1.2.git.

Supplementary information

Supplementary data are available at Bioinformatics online.
Structural optimization of baffle internals for fast particle pyrolysis in a downer reactor using the discrete element method
Authors: Liu Bing
Published: April 2021

The structural optimization of baffle internals for fast pyrolysis of coal with particulate mixing and heat transfer in a downer reactor using the discrete element method (DEM) has been investigated in this research. The pyrolysis terminal temperature at the exit of the downer reactor is not only decided by the volume-feeding-rate ratio of the coal to the sand, but also is affected by the inner structural design of the baffle internals in the downer reactor. As presented in the previous publication of the author, the inhibition from the baffle internals in a downer reactor can improve the particulate-mixing degree and heat carrier, and increase the mean residence time of the coal and heat-carrier particles in the downer reactor. The structure of the baffle internals in the downer reactor mentioned in this research can be optimized by the independently developed 3D soft-sphere model of the DEM programme of a 40-mm baffle length, a 30° baffle-slope angle and at least four baffles designed in the downer reactor, which is beneficial for the process design of coal pyrolysis with a heat carrier in the downer reactor.
BC-TFdb: a database of transcription factor drivers in breast cancer
Authors: Khan Abbas , Khan Taimoor , Nasir Syed Nouman , Ali Syed Shujait , Suleman Muhammad , Rizwan Muhammad , Waseem Muhammad , Ali Shahid , Zhao Xia , Wei Dong-Qing
Published: April 2021

Transcription factors (TFs) are DNA-binding proteins, which regulate many essential biological functions. In several cancer types, TF function is altered by various direct mechanisms, including gene amplification or deletion, point mutations, chromosomal translocations, expression alterations, as well as indirectly by non-coding DNA mutations influencing the binding of the TF. TFs are also actively involved in breast cancer (BC) initiation and progression. Herein, we have developed an open-access database, BC-TFdb (Breast Cancer Transcription Factors database), of curated, non-redundant TF involved in BC. The database provides BC driver TFs related information including genomic sequences, proteomic sequences, structural data, pathway information, mutations information, DNA binding residues, survival and therapeutic resources. The database will be a useful platform for researchers to obtain BC-related TF–specific information. High-quality datasets are downloadable for users to evaluate and develop computational methods for drug designing against BC.

Database URL: https://www.dqweilab-sjtu.com/index.php.
Lowering cholesterol, blood pressure, or both to prevent cardiovascular events: results of 8.7 years of follow-up of Heart Outcomes Evaluation Prevention (HOPE)-3 study participants
Authors: Bosch Jackie , Lonn Eva M , Jung Hyejung , Zhu Jun , Liu Lisheng , Lopez-Jaramillo Patricio , Pais Prem , Xavier Denis , Diaz Rafael , Dagenais Gilles , Dans Antonio , Avezum Alvaro , Piegas Leopoldo S , Parkhomenko Alexander , Keltai Kati , Keltai Matyas , Sliwa Karen , Held Claus , Peters Ronald J G , Lewis Basil S , Jansky Petr , Yusoff Khalid , Khunti Kamlesh , Toff William D , Reid Christopher M , Varigos John , Joseph Philip , Leiter Lawrence A , Yusuf Salim
Published: April 2021

Aims

Rosuvastatin (10 mg per day) compared with placebo reduced major adverse cardiovascular (CV) events by 24% in 12 705 participants at intermediate CV risk after 5.6 years. There was no benefit of blood pressure (BP) lowering treatment in the overall group, but a reduction in events in the third of participants with elevated systolic BP. After cessation of all the trial medications, we examined whether the benefits observed during the active treatment phase were sustained, enhanced, or attenuated.

Methods and results

After the randomized treatment period (5.6 years), participants were invited to participate in 3.1 further years of observation (total 8.7 years). The first co-primary outcome for the entire length of follow-up was the composite of myocardial infarction, stroke, or CV death [major adverse cardiovascular event (MACE)-1], and the second was MACE-1 plus resuscitated cardiac arrest, heart failure, or coronary revascularization (MACE-2). In total, 9326 (78%) of 11 994 surviving Heart Outcomes Prevention Evaluation (HOPE)-3 subjects consented to participate in extended follow-up. During 3.1 years of post-trial observation (total follow-up of 8.7 years), participants originally randomized to rosuvastatin compared with placebo had a 20% additional reduction in MACE-1 [95% confidence interval (CI), 0.64–0.99] and a 17% additional reduction in MACE-2 (95% CI 0.68–1.01). Therefore, over the 8.7 years of follow-up, there was a 21% reduction in MACE-1 (95% CI 0.69–0.90, P = 0.005) and 21% reduction in MACE-2 (95% CI 0.69–0.89, P = 0.002). There was no benefit of BP lowering in the overall study either during the active or post-trial observation period, however, a 24% reduction in MACE-1 was observed over 8.7 years.

Conclusion

The CV benefits of rosuvastatin, and BP lowering in those with elevated systolic BP, compared with placebo continue to accrue for at least 3 years after cessation of randomized treatment in individuals without cardiovascular disease indicating a legacy effect.

Trial Registration Number

NCT00468923
The yeast MER2 gene is required for chromosome synapsis and the initiation of meiotic recombination.
Authors: Rockmill B , Engebrecht J A , Scherthan H , Loidl J , Roeder G S
Published: April 2021

Mutation of the MER2 gene of Saccharomyces cerevisiae confers meiotic lethality. To gain insight into the function of the Mer2 protein, we have carried out a detailed characterization of the mer2 null mutant. Genetic analysis indicates that mer2 completely eliminates meiotic interchromosomal gene conversion and crossing over. In addition, mer2 abolishes intrachromosomal meiotic recombination, both in the ribosomal DNA array and in an artificial duplication. The results of a physical assay demonstrate that the mer2 mutation prevents the formation of meiosis-specific, double-strand breaks, indicating that the Mer2 protein acts at or before the initiation of meiotic recombination. Electron microscopic analysis reveals that the mer2 mutant makes axial elements, which are precursors to the synaptonemal complex, but homologous chromosomes fail to synapse. Fluorescence in situ hybridization of chromosome-specific DNA probes to spread meiotic chromosomes demonstrates that homolog alignment is also significantly reduced in the mer2 mutant. Although the MER2 gene is transcribed during vegetative growth, deletion or overexpression of the MER2 gene has no apparent effect on mitotic recombination or DNA damage repair. We suggest that the primary defect in the mer2 mutant is in the initiation of meiotic genetic exchange.
Autonomously Replicating Macronuclear DNA Pieces Are the Physical Basis of Genetic Coassortment Groups in Tetrahymena thermophila
Authors: Wong Laura , Klionsky Lana , Wickert Steve , Merriam Virginia , Orias Eduardo , Hamilton Eileen P
Published: April 2021

The macronucleus of the ciliate Tetrahymena thermophila contains a fragmented somatic genome consisting of several hundred identifiable chromosome pieces. These pieces are generated by site-specific fragmentation of the germline chromosomes and most of them are represented at an average of 45 copies per macronucleus. In the course of successive divisions of an initially heterozygous macronucleus, the random distribution of alleles of loci carried on these copies eventually generates macronuclei that are pure for one allele or the other. This phenomenon is called phenotypic assortment. We have previously reported the existence of loci that assort together (coassort) and hypothesized that these loci reside on the same macronuclear piece. The work reported here provides new, rigorous genetic support for the hypothesis that macronuclear autonomously replicating chromosome pieces are the physical basis of coassortment groups. Thus, coassortment allows the mapping of the somatic genome by purely genetic means. The data also strongly suggest that the random distribution of alleles in the Tetrahymena macronucleus is due to the random distribution of the MAC chromosome pieces that carry them.
RNA Editing of the DrosophilaparaNa+ Channel Transcript: Evolutionary Conservation and Developmental Regulation
Authors: Hanrahan Christopher J , Palladino Michael J , Ganetzky Barry , Reenan Robert A
Published: April 2021

Post-transcriptional editing of pre-mRNAs through the action of dsRNA adenosine deaminases results in the modification of particular adenosine (A) residues to inosine (I), which can alter the coding potential of the modified transcripts. We describe here three sites in the para transcript, which encodes the major voltage-activated Na+ channel polypeptide in Drosophila, where RNA editing occurs. The occurrence of RNA editing at the three sites was found to be developmentally regulated. Editing at two of these sites was also conserved across species between the D. melanogaster and D. virilis. In each case, a highly conserved region was found in the intron downstream of the editing site and this region was shown to be complementary to the region of the exonic editing site. Thus, editing at these sites would appear to involve a mechanism whereby the edited exon forms a base-paired secondary structure with the distant conserved noncoding sequences located in adjacent downstream introns, similar to the mechanism shown for A-to-I RNA editing of mammalian glutamate receptor subunits (GluRs). For the third site, neither RNA editing nor the predicted RNA secondary structures were evolutionarily conserved. Transcripts from transgenic Drosophila expressing a minimal editing site construct for this site were shown to faithfully undergo RNA editing. These results demonstrate that Na+ channel diversity in Drosophila is increased by RNA editing via a mechanism analogous to that described for transcripts encoding mammalian GluRs.
Ariadne-1: A Vital Drosophila Gene Is Required in Development and Defines a New Conserved Family of RING-Finger Proteins
Authors: Aguilera Miguel , Oliveros Mariano , Martínez-Padrón Manuel , Barbas Julio A , Ferrús Alberto
Published: April 2021

We report the identification and functional characterization of ariadne-1 (ari-1), a novel and vital Drosophila gene required for the correct differentiation of most cell types in the adult organism. Also, we identify a sequence-related gene, ari-2, and the corresponding mouse and human homologues of both genes. All these sequences define a new protein family by the Acid-rich, RING finger, B-box, RING finger, coiled-coil (ARBRCC) motif string. In Drosophila, ari-1 is expressed throughout development in all tissues. The mutant phenotypes are most noticeable in cells that undergo a large and rapid membrane deposition, such as rewiring neurons during metamorphosis, large tubular muscles during adult myogenesis, and photoreceptors. Occasional survivors of null alleles exhibit reduced life span, motor impairments, and short and thin bristles. Single substitutions at key cysteines in each RING finger cause lethality with no survivors and a drastic reduction of rough endoplasmic reticulum that can be observed in the photoreceptors of mosaic eyes. In yeast two-hybrid assays, the protein ARI-1 interacts with a novel ubiquitin-conjugating enzyme, UbcD10, whose sequence is also reported here. The N-terminal RING-finger motif is necessary and sufficient to mediate this interaction. Mouse and fly homologues of both ARI proteins and the Ubc can substitute for each other in the yeast two-hybrid assay, indicating that ARI represents a conserved novel mechanism in development. In addition to ARI homologues, the RBR signature is also found in the Parkinson-disease-related protein Parkin adjacent to an ubiquitin-like domain, suggesting that the study of this mechanism could be relevant for human pathology.
courtless, the Drosophila UBC7 Homolog, Is Involved in Male Courtship Behavior and Spermatogenesis
Authors: Orgad Sara , Rosenfeld Galit , Greenspan Ralph J , Segal Daniel
Published: April 2021

The courtless (col) mutation disrupts early steps of courtship behavior in Drosophila males, as well as the development of their sperm. Most of the homozygous col/col males (78%) do not court at all. Only 5% perform the entire ritual and copulate, yet these matings produce no progeny. The col gene maps to polytene chromosome band 47D. It encodes two proteins that differ in their carboxy termini and are the Drosophila homologs of the yeast ubiquitin-conjugating enzyme UBC7. The col mutation is caused by an insertion of a P element into the 3′ UTR of the gene, which probably disrupts translational regulatory elements. As a consequence, the homozygous mutants exhibit a six- to sevenfold increase in the level of the COL protein. The col product is essential, and deletions that remove the col gene are lethal. During embryonic development col is expressed primarily in the CNS. Our results implicate the ubiquitin-mediated system in the development and function of the nervous system and in meiosis during spermatogenesis.
Deletion of an Insulator Element by the Mutation facet-strawberry in Drosophila melanogaster
Authors: Vazquez Julio , Schedl Paul
Published: April 2021

Eukaryotic chromosomes are thought to be subdivided into a series of structurally and functionally independent units. Critical to this hypothesis is the identification of insulator or boundary elements that delimit chromosomal domains. The properties of a Notch mutation, facet-strawberry (faswb), suggest that this small deletion disrupts such a boundary element. faswb is located in the interband separating polytene band 3C7, which contains Notch, from the distal band 3C6. The faswb mutation alters the structural organization of the chromosome by deleting the interband and fusing 3C7 with 3C6. Genetic studies also suggest that faswb compromises the functional autonomy of Notch by allowing the locus to become sensitive to chromosomal position effects emanating from distal sequences. In the studies reported here, we show that a DNA fragment spanning the faswb region can insulate reporter transgenes against chromosomal position effects and can block enhancer-promoter interactions. Moreover, we find that insulating activity is dependent on sequences deleted in faswb. These results provide evidence that the element defined by the faswb mutation corresponds to an insulator.
Transforming practices of diplomacy: the European External Action Service and digital disinformation
Authors: Hedling Elsa
Published: April 2021

This article explores the transformative role of practices of countering digital disinformation in European Union diplomacy. It argues that an overlooked dimension of the change brought by the rise of digital disinformation is located in the emergence of everyday countering practices. Efforts to counter disinformation have led to the recruitment of new actors with different dispositions and skill sets than those of traditional diplomats and state officials in diplomatic organizations such as the European External Action Service. Focusing on the countering efforts by the East StratCom Task Force, a unit introduced in 2015, the article argues that the composition of actors, the task force's practices and the reorientation in audience perception it reflected, contributed significantly to institutional transformation. Drawing on 23 interviews with key actors and building on recent advancements in international practice theory, the article shows how change and transformation can be studied in practices that have resulted from digitalization in international politics. The article thus contributes to an increased understanding of the digitalization of diplomacy in which new practices can emerge from both deliberate reflection and experimentation.
The Typical Structure of Sets With Small Sumset
Authors: Campos Marcelo , Collares Maurício , Morris Robert , Morrison Natasha , Souza Victor
Published: April 2021

In this paper we determine the number and typical structure of sets of integers with bounded doubling. In particular, improving recent results of Green and Morris, and of Mazur, we show that the following holds for every fixed $\lambda> 2$ and every $k \geqslant (\log n)^4$: if $\omega \rightarrow \infty $ as $n \rightarrow \infty $ (arbitrarily slowly), then almost all sets $A \subset [n]$ with $|A| = k$ and $|A + A| \leqslant \lambda k$ are contained in an arithmetic progression of length $\lambda k/2 + \omega $.
What is the pelvic tilt in acetabular dysplasia and does it change following peri-acetabular osteotomy?
Authors: Roussot Mark A , Salih Saif , Grammatopoulos George , Witt Johan D
Published: April 2021

To quantify the pelvic tilt (PT) in patients with symptomatic acetabular dysplasia and determine if it represents a compensatory mechanism to improve femoral head coverage, we studied a cohort of 16 patients undergoing 32 bilateral staged PAOs for acetabular dysplasia and compared this to a matched cohort of 32 patients undergoing PAO for unilateral acetabular dysplasia all with >1 year follow-up. The change in PT was determined with two validated methods, namely, the sacro-femoral-pubic (SFP) angle and the pubic symphysis to sacroiliac index (PS-SI). Despite an improvement in the lateral centre-edge and Tönnis angles to within normal limits following PAO, patients with unilateral and bilateral acetabular dysplasia have similar PT pre-operatively (8° ± 5°) and post-operatively (9° ± 5°). A change of >5° was observed in only six patients (13%) using the SFP angle, and five patients (10%) using the PS-SI, all increased (posterior rotation of the pelvis). No patients were observed to have a change in PT >10°. The observed PT in our study group is equivalent to that found in the normal population and in patient with symptomatic acetabular retroversion. These findings all suggest that PT is morphological rather than a result of a compensatory mechanism, and even if it was compensatory, it does not appear to reverse significantly following PAO. The target for acetabular reorientation, therefore, remains constant.
The Latest Generation of SEZs: Consumer-Oriented Unilateralism in China’s E-Commerce Trade
Authors: Huang Jie (Jeanne)
Published: April 2021

World Trade Organization multilateralism is driven by manufacturers. However, in China, Cross-border E-commerce Retail Import has spurred a new, consumer-oriented trade unilateralism. Cross-border E-commerce Retail Import prospers within China’s National Cross-Border E-commerce Pilot Cities, which are special economic zones aimed at using unilateral trade liberalization to meet consumers’ growing demands for high-quality foreign products. Cross-border E-commerce Retail Import enhances consumer benefits beyond reducing customer formalities and tax rates and lowering product prices. It re-conceptualizes consumer protection by treating consumers as diverse individuals rather than as a homothetic group. It also empowers consumers by making them ‘importers’ to minimize behind-the-border trade barriers. Cross-border E-commerce Retail Import warrants a rethinking of World Trade Organization multilateralism from its initial focus on corporations and capital owners to a revised focus on consumers.
Dietary Intake of Branched Chain Amino Acids and Breast Cancer Risk in the NHS and NHS II Prospective Cohorts
Authors: Tobias Deirdre K , Chai Boyang , Tamimi Rulla M , Manson JoAnn E , Hu Frank B , Willett Walter C , Eliassen A Heather
Published: April 2021

Background

Branched chain amino acids (BCAAs) are essential amino acids common throughout the US diet. Although circulating BCAAs have been implicated in insulin resistance and some obesity-related cancers, the relationship between dietary intake of BCAAs and incident breast cancer is unknown. We sought to evaluate the association between long-term dietary intakes of BCAAs and invasive breast cancer risk.

Methods

Our analyses included 196 161 women from the Nurses’ Health Study and Nurses’ Health Study II longitudinal cohorts. Average intakes of total and individual BCAAs (isoleucine, leucine, valine) were estimated from repeated diet questionnaires and incident self-reported breast cancer cases were confirmed via medical record review. Cox proportional hazards models, adjusted for reproductive history, lifestyle, body mass index, and other breast cancer risk factors, were used to estimate hazard ratios and 95% confidence intervals.

Results

We observed 10 046 incident cases of breast cancer over a median of 20.8 years of follow-up. No associations between dietary intakes of total or individual BCAAs with breast cancer risk were observed. Compared with women in the bottom quintile of BCAA intake, the hazard ratio of breast cancer for those in the top quintile was 1.05 (95% confidence interval = 0.98 to 1.12; 2-sided Ptrend = .20). Findings were consistent across molecular subtypes and according to type 2 diabetes diagnosis and body mass index categories.

Conclusions

Dietary intakes of BCAAs are not likely a risk factor for breast cancer.
The tonoplast-localized transporter OsNRAMP2 is involved in iron homeostasis and affects seed germination in rice
Authors: Li Yun , Li Jingjun , Yu Yihong , Dai Xia , Gong Changyi , Gu Dongfang , Xu Ending , Liu Yiheng , Zou Yu , Zhang Peijiang , Chen Xi , Zhang Wei
Published: April 2021

Vacuolar storage of iron (Fe) is important for Fe homeostasis in plants. When sufficient, excess Fe could be stored in vacuoles for remobilization in the case of Fe deficiency. Although the mechanism of Fe remobilization from vacuoles is critical for crop development under low Fe stress, the transporters that mediate vacuolar Fe translocation into the cytosol in rice remains unknown. Here, we showed that under high Fe2+ concentrations, the Δccc1 yeast mutant transformed with the rice natural resistance-associated macrophage protein 2 gene (OsNRAMP2) became more sensitive to Fe toxicity. In rice protoplasts and transgenic plants expressing Pro35S:OsNRAMP2-GFP, OsNRAMP2 was localized to the tonoplast. Vacuolar Fe content in osnramp2 knockdown lines was higher than in the wild type, while the growth of osnramp2 knockdown plants was significantly influenced by Fe deficiency. Furthermore, the germination of osnramp2 knockdown plants was arrested. Conversely, the vacuolar Fe content of Pro35S:OsNRAMP2-GFP lines was significantly lower than in the wild type, and overexpression of OsNRAMP2 increased shoot biomass under Fe deficiency. Taken together, we propose that OsNRAMP2 transports Fe from the vacuole to the cytosol and plays a pivotal role in seed germination.
Pathogenesis of acephalic spermatozoa syndrome caused by SUN5 variant
Authors: Zhang Duo , Huang Wu-Jian , Chen Guo-Yong , Dong Li-Hong , Tang Ying , Zhang Hui , Li Qing-Qin , Mei Xiao-Yan , Wang Zhi-Hong , Lan Feng-Hua
Published: April 2021

Acephalic spermatozoa syndrome (ASS) is a rare teratozoospermia that leads to male infertility. Previous work suggested a genetic origin. Variants of Sad1 and UNC84 domain containing 5 (SUN5) are the main genetic cause of ASS; however, its pathogenesis remains unclear. Here, we performed whole-exome sequencing in 10 unrelated ASS and identified 2 homozygous variants, c.381delA[p.V128Sfs7*] and c.675C>A[p.Y225X], and 1 compound variant, c.88 C > T[p.R30X] and c.381 delA [p.V128Sfs7*], in SUN5 in 4 patients. The c.381delA variant had been identified as pathogenic in previous reports, while c.675C>A and c.88 C > T were two novel variants which could lead to a premature termination codon (PTC) and resulted in loss of SUN5, and may also be pathogenic. SUN5 mRNA and protein were present at very low levels in ASS patients with SUN5 nonsense mutation. Furthermore, the distribution of outer dense fiber protein 1 (ODF1) and Nesprin3 was altered in sperm of ASS patients with SUN5 variants. The co-immunoprecipitation analysis indicated that SUN5 and ODF1, SUN5 and Nesprin3, and ODF1 and Nesprin3 interacted with each other in transfected HEK293T cells. Thus, we propose that SUN5, Nesprin3, and ODF1 may form a ‘triplet’ structure through interactions at neck of sperm. When gene variants resulted in a loss of SUN5, the ‘triplet’ structure disappears and then the head-tail junction becomes fragile, leading to the occurrence of ASS.
Grand scale genome manipulation via chromosome swapping in Escherichia coli programmed by three one megabase chromosomes
Authors: Yoneji Tatsuya , Fujita Hironobu , Mukai Takahito , Su’etsugu Masayuki
Published: April 2021

In bacterial synthetic biology, whole genome transplantation has been achieved only in mycoplasmas that contain a small genome and are competent for foreign genome uptake. In this study, we developed Escherichia coli strains programmed by three 1-megabase (Mb) chromosomes by splitting the 3-Mb chromosome of a genome-reduced strain. The first split-chromosome retains the original replication origin (oriC) and partitioning (par) system. The second one has an oriC and the par locus from the F plasmid, while the third one has the ori and par locus of the Vibrio tubiashii secondary chromosome. The tripartite-genome cells maintained the rod-shaped form and grew only twice as slowly as their parent, allowing their further genetic engineering. A proportion of these 1-Mb chromosomes were purified as covalently closed supercoiled molecules with a conventional alkaline lysis method and anion exchange columns. Furthermore, the second and third chromosomes could be individually electroporated into competent cells. In contrast, the first split-chromosome was not able to coexist with another chromosome carrying the same origin region. However, it was exchangeable via conjugation between tripartite-genome strains by using different selection markers. We believe that this E. coli-based technology has the potential to greatly accelerate synthetic biology and synthetic genomics.