bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation of Plastic Oil Blends on CRDi Engine for Various Fuel Injection Pressures
Authors: Balaji G. , Karthik M. , Dinagaran G. , Vasanth Kumar P.
Published: April 2021

Common Rail Direct Engine (CRDI) engines are used for transportation and other sectors due to their high fuel conversion efficiencies. Waste plastic pyrolysis oil can be a substitute to the depleting petroleum reserves. Plastic oils are durable and takes longer time to degrade because of stronger molecular bonds and it repel to natural processes of degradation. This investigation deals with the effect of increasing the fuel blend ratio and with increasing the fuel injection pressures on single cylinder, CRDI diesel engine using plastic oil and diesel blend. The fuel blend varies from 5:95%, 10:90% and 15:85% (Plastic pyrolysis oil and diesel) respectively with various fuel injection pressures of 400 bar, 500 bar and 600 bar. The emission, performance and combustion characteristics were evaluated and analyzed in this work. Plastic oil blends were able to operate in diesel engines without any engine modifications. The results shows the brake thermal efficiency increases with the increasing fuel injection pressure. The engine with the fuel injection pressure of 600 bar gives better brake thermal efficiency at the full load condition for the 15PDB fuel blend. Hence it was concluded that the increasing the pressure, increases the performance and decreases the emissions.
A SDFEM for Singularly Perturbed System of Convection-Diffusion Delay Differential Equations
Authors: Senthilkumar L.S. , Subburayan V.
Published: April 2021

In this article, we consider a system of convection-diffusion equations with delay terms. When a parameter multiplying the second order derivatives in the equations is small, boundary layers as well as interior layers appear in their solutions. A numerical method based on finite element and Shishkin mesh is presented. We derive an error estimate of orderO(N−1log2N) in the energy norm with respect to the parameter using the streamline-diffusion finite element method. Numerical experiments are also presented to support our theoretical results.
Study on efficient removal of NO from CI engine exhaust gas by wet scrubbing method using NaOH solution
Authors: Premkumar S. , Balaji G.
Published: April 2021

Pollutants like Nitrogen oxide (NO) and Hydrocarbon (HC) exhausted from automobiles are very harmful. The scrubber method is most widely used in power plants and marine engines for emission control. In this study, the Diesel Plastic oil blend (DPB) and wet scrubber method are employed to reduce the pollutants. The scrubber treatment with NaOH (Sodium hydroxide) solution is used to reduce emissions in the Internal Combustion (IC) engine. The NO is drastically reduced. Hydrocarbon (HC) is also gradually reduced using the NaOH solution. The DPB was tested in a computerized, water-cooled, 4-stroke, single-cylinder, 5.2 kW diesel engine for analyzing its performance and emission characteristics with a scrubber. The experiments are conducted under different loading conditions (0, 1.3, 2.6, 3.9, and 5.2 kW). At 5.2 kW loading condition, the diesel engine running on DPB with scrubber reduced the NO emission up to 25% and HC emission up to 14%.
Test of the retractable guidance system installed on the level 960 m in the Leon IV shaft in Rydułtowy Coal Mine, Poland
Authors: Kamiński P , Prostański D , Dyczko A
Published: April 2021

Rope guidance of the conveyances is a reliable and convenient way of guiding cages and skips in the mine shafts and it is used in numerous underground mines all over the world. However it is not popular in Polish coal mines. Most of the Polish copper and coal mines operate on multiple levels, which requires mine shafts and hoists to support more than one level. In such situation it is necessary to install some kind of chairing system on the levels, i.e. stiff guides in their vicinity. Conveyance’s movement through the stiff guides on the level requires its speed reduction, which in turn leads to lowering of the hoist’s effectiveness. To avoid such situation, retractable guidance system was introduced on the level 960 in the Leon IV shaft in Rydułtowy Coal Mine, Poland. This paper presents the idea of the retractable guidance system, as well as calculations and measurements carried out to prove that the system is safe and reliable.
Innovative Concept of Production Support System for the LW Bogdanka Mine
Authors: Dyczko A , Malec M
Published: April 2021

The research work results, presented in the article, describe a system concerning the management of a production line in the aspect of stabilization and improvement of the run-of-mine quality and maximization of economic effects. Basing on the geological deposit model, the authors concentrated on designing mining operations and on planning production parameters. Special attention was paid to a development of the mine workings design module, the mining operations scheduling module, the module for mixing and optimization from the quality point of view as well as the module for mining operations revenues and forecasts of costs. Forecasting the production quality, planning and integration of mining processes with coal preparation processes and sales are discussed in detail. The article is ended with some recommendations of general character, including quality management at the stage of mining and production planning, quality monitoring at the stage of coal mining, and its preparation. The system is oriented onto production quality forecasting and onto an integration of mining, preparation and sales planning.
‘Amber Alert’ or ‘Heatwave Warning’: The Role of Linguistic Framing in Mediating Understandings of Early Warning Messages about Heatwaves and Cold Spells
Authors: Tang Chris
Published: April 2021

Periods of extremely hot and cold weather can cause significant mortality and morbidity in both temperate and more extreme climates. In the UK, their occurrence prompts the issuing of number and colour coded warnings providing an assessment of the level of risk. These are designed to minimize health impact by prompting timely and appropriate mitigating actions by the public. Drawing upon the interdisciplinary notion of framing, I report on a study that identified a central role for language in mediating how these warnings are interpreted and evaluated. I use an innovative approach that combines the quantitative tools of corpus linguistics to identify the language used to represent warnings and the risks of extreme temperature in the mass media, with qualitative analysis of focus group discussions of typical texts. A comparison of both datasets indicates a multi-layered interactivity between the myriad ways in which language can give salience to aspects of a risk scenario and an interpreter’s knowledge and perception of a threat, and that underlying such interactions, is the conceptualization of risk as scalar property.
Review of multi-omics data resources and integrative analysis for human brain disorders
Authors: Dong Xianjun , Liu Chunyu , Dozmorov Mikhail
Published: April 2021

In the last decade, massive omics datasets have been generated for human brain research. It is evolving so fast that a timely update is urgently needed. In this review, we summarize the main multi-omics data resources for the human brains of both healthy controls and neuropsychiatric disorders, including schizophrenia, autism, bipolar disorder, Alzheimer’s disease, Parkinson’s disease, progressive supranuclear palsy, etc. We also review the recent development of single-cell omics in brain research, such as single-nucleus RNA-seq, single-cell ATAC-seq and spatial transcriptomics. We further investigate the integrative multi-omics analysis methods for both tissue and single-cell data. Finally, we discuss the limitations and future directions of the multi-omics study of human brain disorders.
Cooperative sequence clustering and decoding for DNA storage system with fountain codes
Authors: Jeong Jaeho , Park Seong-Joon , Kim Jae-Won , No Jong-Seon , Jeon Ha Hyeon , Lee Jeong Wook , No Albert , Kim Sunghwan , Park Hosung
Published: April 2021

Motivation

In DNA storage systems, there are tradeoffs between writing and reading costs. Increasing the code rate of error-correcting codes may save writing cost, but it will need more sequence reads for data retrieval. There is potentially a way to improve sequencing and decoding processes in such a way that the reading cost induced by this tradeoff is reduced without increasing the writing cost. In past researches, clustering, alignment and decoding processes were considered as separate stages but we believe that using the information from all these processes together may improve decoding performance. Actual experiments of DNA synthesis and sequencing should be performed because simulations cannot be relied on to cover all error possibilities in practical circumstances.

Results

For DNA storage systems using fountain code and Reed-Solomon (RS) code, we introduce several techniques to improve the decoding performance. We designed the decoding process focusing on the cooperation of key components: Hamming-distance based clustering, discarding of abnormal sequence reads, RS error correction as well as detection and quality score-based ordering of sequences. We synthesized 513.6 KB data into DNA oligo pools and sequenced this data successfully with Illumina MiSeq instrument. Compared to Erlich’s research, the proposed decoding method additionally incorporates sequence reads with minor errors which had been discarded before, and thus was able to make use of 10.6–11.9% more sequence reads from the same sequencing environment, this resulted in 6.5–8.9% reduction in the reading cost. Channel characteristics including sequence coverage and read-length distributions are provided as well.

Availability and implementation

The raw data files and the source codes of our experiments are available at: https://github.com/jhjeong0702/dna-storage.
Decoding the transcriptome of pre-granulosa cells during the formation of primordial follicles in the mouse
Authors: Fukuda Kurumi , Muraoka Masafumi , Kato Yuzuru , Saga Yumiko
Published: April 2021

Primordial follicles, a finite reservoir of eggs in mammalian ovaries, are composed of a single oocyte and its supporting somatic cells, termed granulosa cells. Although their formation may require reciprocal interplay between oocytes and pre-granulosa cells, precursors of granulosa cells, little is known about the underlying mechanisms. We addressed this issue by decoding the transcriptome of pre-granulosa cells during the formation of primordial follicles. We found that marked gene expression changes, including extracellular matrix, cell adhesion, and several signaling pathways, occur along with primordial follicle formation. Importantly, differentiation of Lgr5-EGFP-positive pre-granulosa cells to FOXL2-positive granulosa cells was delayed in mutant ovaries of the germ cell-specific genes Nanos3 and Figla, accompanied by perturbed gene expression in mutant pre-granulosa cells. These results suggest that proper development of oocytes is required for the differentiation of pre-granulosa cells. Our data provide a valuable resource for understanding the gene regulatory networks involved in the formation of primordial follicles.
Learning curve of robotic distal and total gastrectomy
Authors: Zheng-yan Li , Feng Qian , Yan Shi , Ji-Peng Li , Qing-Chuan Zhao , Bo Tang , Rui-Zi Gao , Zhi-Guo Shan , Xia Lin , Qing Feng , Tao He , Zi-Yan Luo , Zhi Wang , Pei-wu Yu , Yong-Liang Zhao
Published: April 2021

Background

This study aims to assess the learning curve of robotic distal gastrectomy (RDG) and robotic total gastrectomy (RTG) for gastric cancer.

Methods

Data on consecutive patients who underwent robotic gastrectomy for gastric cancer by five surgeons between March 2010 and August 2019 at two high-volume institutions were collected. The learning curve was determined based on the analyses of operation time and postoperative complications within 30 days. Cumulative sum analysis (CUSUM) and risk-adjusted-CUSUM (RA-CUSUM) were applied to identify the turning points (TPs).

Results

A total of 899 consecutive patients were included. The mean number of patients needed to overcome the learning curve for operation time of RDG and RTG were 22 and 20, respectively. The number of patients needed to overcome the learning curve for postoperative complications after RDG and RTG were 23 and 18, respectively. The surgical outcomes in the post-TP group were better than in the pre-TP group and improved as surgeons’ experience increased. Also, increased case numbers in RDG promoted the RTG learning process.

Conclusion

The present study demonstrated a substantial influence of surgical cumulative volume on improved surgical outcomes in robotic gastrectomy. Increased experience in RDG may help surgeons to achieve proficiency faster in RTG.
Comment on: Global variation in anastomosis and end colostomy formation following left-sided colorectal resection
Authors: Schaps D , Alvarez C E
Published: April 2021

Is the corresponding author a member of a Strategic Partner Society (50% discount on article publication charge):
Motor and cognitive outcomes of cerebello-spinal stimulation in neurodegenerative ataxia
Authors: Benussi Alberto , Cantoni Valentina , Manes Marta , Libri Ilenia , Dell’Era Valentina , Datta Abhishek , Thomas Chris , Ferrari Camilla , Di Fonzo Alessio , Fancellu Roberto , Grassi Mario , Brusco Alfredo , Alberici Antonella , Borroni Barbara
Published: April 2021

Cerebellar ataxias represent a heterogeneous group of disabling disorders characterized by motor and cognitive disturbances, for which no effective treatment is currently available. In this randomized, double-blind, sham-controlled trial, followed by an open-label phase, we investigated whether treatment with cerebello-spinal transcranial direct current stimulation (tDCS) could improve both motor and cognitive symptoms in patients with neurodegenerative ataxia at short and long-term. Sixty-one patients were randomized in two groups for the first controlled phase. At baseline (T0), Group 1 received placebo stimulation (sham tDCS) while Group 2 received anodal cerebellar tDCS and cathodal spinal tDCS (real tDCS) for 5 days/week for 2 weeks (T1), with a 12-week (T2) follow-up (randomized, double-blind, sham controlled phase). At the 12-week follow-up (T2), all patients (Group 1 and Group 2) received a second treatment of anodal cerebellar tDCS and cathodal spinal tDCS (real tDCS) for 5 days/week for 2 weeks, with a 14-week (T3), 24-week (T4), 36-week (T5) and 52-week follow-up (T6) (open-label phase). At each time point, a clinical, neuropsychological and neurophysiological evaluation was performed. Cerebellar-motor cortex connectivity was evaluated using transcranial magnetic stimulation. We observed a significant improvement in all motor scores (scale for the assessment and rating of ataxia, international cooperative ataxia rating scale), in cognition (evaluated with the cerebellar cognitive affective syndrome scale), in quality-of-life scores, in motor cortex excitability and in cerebellar inhibition after real tDCS compared to sham stimulation and compared to baseline (T0), both at short and long-term. We observed an addon-effect after two repeated treatments with real tDCS compared to a single treatment with real tDCS. The improvement at motor and cognitive scores correlated with the restoration of cerebellar inhibition evaluated with transcranial magnetic stimulation. Cerebello-spinal tDCS represents a promising therapeutic approach for both motor and cognitive symptoms in patients with neurodegenerative ataxia, a still orphan disorder of any pharmacological intervention.
Visual agnosia and imagery after Lissauer
Authors: Bartolomeo Paolo
Published: April 2021

This year marks the 130th anniversary of the untimely death of Heinrich Lissauer (1861–91). Paolo Bartolomeo explores how the anatomical account of dissociations between perception and imagery deficits proposed by Lissauer in his 1890 article on visual agnosia, resonates with the present debate on the neural bases of visual mental imagery.
Driveline exit-site care protocols in patients with left ventricular assist devices: a systematic review
Authors: Koken Zeliha Ozdemir , Yalcin Yunus C , van Netten Diana , de Bakker Chantal C , van der Graaf Maaike , Kervan Umit , Verkaik Nelianne J , Caliskan Kadir
Published: April 2021

OBJECTIVES

Driveline infections continue to be a significant complication following left ventricular assist device (LVAD) implantation. Driveline exit-site care is crucial for the prevention of infections; however, there are no uniform guidelines. The goal of this study was to provide an overview of the currently published driveline exit-site care protocols in patients with LVAD.

METHODS

A systematic literature review was performed. Studies before 15 December 2020 were included if the number of driveline infections was a primary outcome and the driveline exit-site care protocol was explained.

RESULTS

Eleven articles were included in the systematic review, including 1602 patients with LVADs. The median of the frequency of driveline infections in the articles was 13.8% with a range of 0–52.6%. There was a marked variability in the methods of care of driveline exit sites, without a standardized driveline dressing technique in patients with LVADs. The frequency of driveline infections was 6–7.5% in studies using a dressing kit that included chlorhexidine, a silver-based dressing and an anchoring device. Furthermore, there was variability in the anchoring devices and the frequency of dressing changes, which varied from daily to weekly. No specific anchoring device or change frequency was found to be superior.

CONCLUSIONS

Based on this systematic review, driveline exit care protocols that included chlorhexidine, a silver-based dressing, the use of an anchoring device and dressing kits might be best in reducing driveline infection rates. However, prospective studies with larger cohorts are needed to establish the optimal protocol for driveline exit-site care.
A heart-team hybrid approach for atrial fibrillation: a single-centre long-term clinical outcome cohort study
Authors: Dunnington Gansevoort H , Pierce Carrie L , Eisenberg Susan , Bing Liem L , Chang-Sing Peter , Kaiser Daniel W , Burk Shelby , Moulton Linda C , Kiankhooy Armin
Published: April 2021

OBJECTIVES

The Cox-maze IV is the gold standard for surgical ablation of atrial fibrillation (AF). A heart-team hybrid approach using selected epicardial thoracoscopic surgical ablations and completion endocardial ablations to replicate the Cox-maze IV lesion set has gained popularity and early results have been promising. We herein report our single-centre long-term clinical outcomes using the heart-team hybrid approach with 455 patients.

METHODS

From 1 March 2013 to 1 July 2019, we prospectively collected data on all patients referred to our heart team for rhythm-control strategy for AF. Baseline characteristics, procedural complications and long-term freedom from AF (FFAF) both on and off anti-arrhythmic drug therapy were analysed. Ambulatory monitoring (>7 days) was obtained at 3 months and annually thereafter.

RESULTS

Four hundred and fifty-five patients completed the hybrid approach. Four hundred and forty-five (97.8%) patients had non-paroxysmal AF (long-standing persistent AF n = 249, 54.7%; persistent AF n = 196, 43.1%; paroxysmal AF n = 10, 2.2%). Average duration of AF was 5.9 ± 6.1 years. Average left atrial diameter was 4.8 ± 0.8 cm. FFAF at 3, 12, 24 and 36 months was 92%, 87%, 81% and 72%, respectively. FFAF without the use of anti-arrhythmic medications was 75%, 81%, 76% and 66%. Any surgical complications occurred in 28 (6.1%) patients.

CONCLUSIONS

A heart-team hybrid strategy for the treatment of AF is safe and effective. In a predominantly non-paroxysmal population with AF, at the 3-year follow-up, FFAF in patients on and off anti-arrhythmic drugs approaches that of patients who had the Cox-maze IV.
COVID-SCORE Spain: public perceptions of key government COVID-19 control measures
Authors: White Trenton M , Cash-Gibson Lucinda , Martin-Moreno Jose M , Matesanz Rafael , Crespo Javier , Alfonso-Sanchez Jose L , Villapol Sonia , El-Mohandes Ayman , Lazarus Jeffrey V
Published: April 2021

Background

Spain was initially one of the countries most affected by the coronavirus disease 2019 (COVID-19) pandemic. In June 2020, the COVID-SCORE-10 study reported that the Spanish public’s perception of their government’s response to the pandemic was low. This study examines these perceptions in greater detail.

Methods

We employed an ordered logistic regression analysis using COVID-SCORE-10 data to examine the Spanish public’s perception of 10 key aspects of their government’s COVID-19 control measures. These included support for daily needs, mental and general health services, communication, information and coordination, which were examined by gender, age, education level, having been affected by COVID-19 and trust in government’s success in addressing unexpected health threats.

Results

‘Trust in the government’ showed the greatest odds of positive perception for the 10 measures studied. Odds of positive perception of communication significantly varied by gender, education level and having been affected by COVID-19, whereas for information and coordination of disease control, odds significantly varied by gender and having been affected by COVID-19. Odds of positive perception for access to mental health services significantly varied by gender and education level. Age was not significant.

Conclusion

Public perception of the government’s pandemic response in Spain varied by socio-demographic and individual variables, particularly by reported trust in the government. Fostering public trust during health threats may improve perception of response efforts. Future efforts should tailor interventions that consider gender, education level and whether people have been affected by COVID-19.
Prevalence and correlates of physical inactivity in adults across 28 European countries
Authors: Nikitara Katerina , Odani Satomi , Demenagas Nektarios , Rachiotis George , Symvoulakis Emmanouil , Vardavas Constantine
Published: April 2021

Background

Physical activity/inactivity is impacted by a plethora of intertwined factors. There are a limited number of studies on physical activity/inactivity that provide a European cross-country perspective. This study aims to present the prevalence and correlates of physical activity in adults across the 28 European Union (EU) member states.

Methods

This is a secondary dataset analysis of the Special Eurobarometer 472 data on physical activity. The cross-sectional survey was conducted during December 2–11 in 2017 across 28 European countries. The data consisted of ∼1000 respondents aged ≧15 years per country. The current analysis was restricted to adults aged 18–64 years (n = 19 645).

Results

More than one in three (36.2%, 95% CI: 35.1–37.3) adults in the EU were physically inactive, with substantial cross-country differences noted. Women were less likely than men to be adequately or highly physically active (aOR: 0.86, 95% CI: 0.78–0.95). Similarly, adults at the age of 40–54 (aOR: 0.65, 95% CI: 0.52–0.81) and 55–64 (aOR: 0.61, 95% CI: 0.49–0.77) were less likely to have moderate or high levels of physical activity in comparison with those 18–24 years of age. Finally, high SES was positively associated with physical activity (aOR: 1.4, 95% CI: 1.16–1.69).

Conclusions

A notable percentage of adults in Europe are physically inactive. Further research is needed to elucidate the factors behind the cross-country differences and identify potential policy actions that may support adopting a physically active lifestyle and decrease the inequalities related to physical activity across Europe.
Host-derived extracellular vesicles for antimicrobial defense
Authors: Brakhage Axel A , Zimmermann Ann-Kathrin , Rivieccio Flora , Visser Corissa , Blango Matthew G
Published: April 2021

Extracellular vesicles are of increasing importance in the clinic, as diagnostics for complex diseases and as potential delivery systems for therapeutics. Over the past several decades, extracellular vesicles have emerged as a widespread, conserved mechanism of intercellular and interkingdom communication. The ubiquitous distribution of extracellular vesicles across life offers at least two compelling opportunities: first a path forward in the design of targeted antimicrobial delivery systems; and second, a new way to view host pathogenesis during infection. Both avenues of research are well underway. In particular, preliminary studies showing that plant and human host-derived extracellular vesicles can deliver natural antimicrobial cargos to invading fungal and bacterial pathogens are captivating. Further, modification of host extracellular vesicle populations may ultimately lead to enhanced killing and serve as a starting point for the development of more advanced therapeutic options, especially against difficult to treat pathogens. Despite the rapid pace of growth surrounding extracellular vesicle biology, many questions remain unanswered. For example, the heterogeneity of vesicle populations continues to be a confounding factor in ascribing clear functions to a vesicular subset, and the molecular cargos responsible for specific antimicrobial actions of extracellular vesicles during infection remain especially poorly described. In this short review, we will summarize the current state of affairs surrounding the antimicrobial function, and potential, of host-derived extracellular vesicles.
Homoeolog Inference Methods Requiring Bidirectional Best Hits or Synteny Miss Many Pairs
Authors: Glover Natasha , Sheppard Shaoline , Dessimoz Christophe
Published: April 2021

Homoeologs are pairs of genes or chromosomes in the same species that originated by speciation and were brought back together in the same genome by allopolyploidization. Bioinformatic methods for accurate homoeology inference are crucial for studying the evolutionary consequences of polyploidization, and homoeology is typically inferred on the basis of bidirectional best hit (BBH) and/or positional conservation (synteny). However, these methods neglect the fact that genes can duplicate and move, both prior to and after the allopolyploidization event. These duplications and movements can result in many-to-many and/or nonsyntenic homoeologs—which thus remain undetected and unstudied. Here, using the allotetraploid upland cotton (Gossypium hirsutum) as a case study, we show that conventional approaches indeed miss a substantial proportion of homoeologs. Additionally, we found that many of the missed pairs of homoeologs are broadly and highly expressed. A gene ontology analysis revealed a high proportion of the nonsyntenic and non-BBH homoeologs to be involved in protein translation and are likely to contribute to the functional repertoire of cotton. Thus, from an evolutionary and functional genomics standpoint, choosing a homoeolog inference method which does not solely rely on 1:1 relationship cardinality or synteny is crucial for not missing these potentially important homoeolog pairs.
Mutations in Recombinational Repair and in Checkpoint Control Genes Suppress the Lethal Combination of srs2Δ With Other DNA Repair Genes in Saccharomyces cerevisiae
Authors: Klein Hannah L
Published: April 2021

The SRS2 gene of Saccharomyces cerevisiae encodes a DNA helicase that is active in the postreplication repair pathway and homologous recombination. srs2 mutations are lethal in a rad54Δ background and cause poor growth or lethality in rdh54Δ, rad50Δ, mre11Δ, xrs2Δ, rad27Δ, sgs1Δ, and top3Δ backgrounds. Some of these genotypes are known to be defective in double-strand break repair. Many of these lethalities or poor growth can be suppressed by mutations in other genes in the DSB repair pathway, namely rad51, rad52, rad55, and rad57, suggesting that inhibition of recombination at a prior step prevents formation of a lethal intermediate. Lethality of the srs2Δ rad54Δ and srs2Δ rdh54Δ double mutants can also be rescued by mutations in the DNA damage checkpoint functions RAD9, RAD17, RAD24, and MEC3, indicating that the srs2 rad54 and srs2 rdh54 mutant combinations lead to an intermediate that is sensed by these checkpoint functions. When the checkpoints are intact the cells never reverse from the arrest, but loss of the checkpoints releases the arrest. However, cells do not achieve wild-type growth rates, suggesting that unrepaired damage is still present and may lead to chromosome loss.
Genetic Involvement of a cAMP-Dependent Protein Kinase in a G Protein Signaling Pathway Regulating Morphological and Chemical Transitions in Aspergillus nidulans
Authors: Shimizu Kiminori , Keller Nancy P
Published: April 2021

In the filamentous fungus Aspergillus nidulans, a heterotrimeric G protein α-subunit and an RGS domain protein, encoded by fadA and flbA, respectively, regulate production of the carcinogenic metabolite sterigmatocystin (ST) and asexual spores (i.e., conidia). We investigated the genetic involvement of the cAMP-dependent protein kinase catalytic subunit (PkaA), a potential downstream target of FadA activity, in ST production and conidiation. Relative to wild type, sporulation was decreased in the pkaA overexpression strain but was not totally absent, as occurs in ΔflbA or fadAG42R (fadA-dominant active) strains. Deletion of pkaA resulted in a hyper-conidiating strain with limited radial growth. This phenotype was epistatic to mutation in flbA or fadA; the double mutants ΔpkaA; ΔflbA and ΔpkaA; fadAG42R recovered sporulation and their radial growth was severely restricted. PkaA overexpression also negatively regulated AflR, the ST biosynthesis-specific transcription factor, both transcriptionally and post-transcriptionally. Deletion of pkaA restored ST production in the ΔflbA background but not in the fadAG42R background. These data provide genetic evidence that the FlbA/FadA signaling pathway regulating ST production and morphological development is partially mediated through PkaA.
Trichinella spiralismtDNA: A Nematode Mitochondrial Genome That Encodes a Putative ATP8 and Normally Structured tRNAs and Has a Gene Arrangement Relatable to Those of Coelomate Metazoans
Authors: Lavrov Dennis V , Brown Wesley M
Published: April 2021

The complete mitochondrial DNA (mtDNA) of the nematode Trichinella spiralis has been amplified in four overlapping fragments and 16,656 bp of its sequence has been determined. This sequence contains the 37 genes typical of metazoan mtDNAs, including a putative atp8, which is absent from all other nematode mtDNAs examined. The genes are transcribed from both mtDNA strands and have an arrangement relatable to those of coelomate metazoans, but not to those of secernentean nematodes. All protein genes appear to initiate with ATN codons, typical for metazoans. Neither TTG nor GTT start codons, inferred for several genes of other nematodes, were found. The 22 T. spiralis tRNA genes fall into three categories: (i) those with the potential to form conventional “cloverleaf” secondary structures, (ii) those with TΨC arm + variable arm replacement loops, and (iii) those with DHU-arm replacement loops. Mt-tRNA(R) has a 5′-UCG-3′ anticodon, as in most other metazoans, instead of the very unusual 5′-ACG-3′ present in the secernentean nematodes. The sequence also contains a large repeat region that is polymorphic in size at the population and/or individual level.
Genetic Mapping of Quantitative Trait Loci Governing Longevity of Caenorhabditis elegans in Recombinant-Inbred Progeny of a Bergerac-BO × RC301 Interstrain Cross
Authors: Ayyadevara Srinivas , Ayyadevara Rajani , Hou Sen , Thaden John J , Reis Robert J Shmookler
Published: April 2021

Recombinant-inbred populations, generated from a cross between Caenorhabditis elegans strains Bergerac-BO and RC301, were used to identify quantitative trait loci (QTL) affecting nematode longevity. Genotypes of young controls and longevity-selected worms (the last-surviving 1% from a synchronously aged population) were assessed at dimorphic transposon-specific markers by multiplex polymerase chain reaction. The power of genetic mapping was enhanced, in a novel experimental design, through map expansion by accrual of recombinations over several generations, internally controlled longevity selection from a genetically heterogeneous, homozygous population, and selective genotyping of extremely long-lived worms. Analysis of individual markers indicated seven life-span QTL, situated near markers on chromosomes I (tcbn2), III (stP127), IV (stP13), V (stP6, stP23, and stP128), and X (stP41). These loci were corroborated, and mapped with increased precision, by nonparametric interval mapping—which supported all loci implicated by single-marker analysis. In addition, a life-span QTL on chromosome II (stP100-stP196), was significant only by interval mapping. Congenic lines were constructed for the longevity QTL on chromosomes III and X, by backcrossing the Bergerac-BO QTL allele into an RC301 background with selection for flanking markers. Survival data for these lines demonstrated consistent and significant effects of each QTL on life span.
Molecular Dissection of the 5′ Region ofno-on-transientAofDrosophila melanogasterRevealscis-Regulation by AdjacentdGpi1Sequences
Authors: Sandrelli Federica , Campesan Susanna , Rossetto Maria Giovanna , Benna Clara , Zieger Emanuela , Megighian Aram , Couchman Martin , Kyriacou Charalambos P , Costa Rodolfo
Published: April 2021

The nonA gene of Drosophila melanogaster is important for normal vision, courtship song, and viability and lies ∼350 bp downstream of the dGpi1 gene. Full rescue of nonA mutant phenotypes can be achieved by transformation with a genomic clone that carries ∼2 kb of 5′ regulatory material and that encodes most of the coding sequence of dGpi1. We have analyzed this 5′ region by making a series of deleted fragments, fusing them to yeast GAL4 sequences, and driving UAS-nonA expression in a mutant nonA background. Regions that both silence and enhance developmental tissue-specific expression of nonA and that are necessary for generating optomotor visual responses are identified. Some of these overlap the dGpi1 sequences, revealing cis-regulation by neighboring gene sequences. The largest 5′ fragment was unable to rescue the normal electroretinogram (ERG) consistently, and no rescue at all was observed for the courtship song phenotype. We suggest that sequences within the nonA introns that were missing in the UAS-nonA cDNA may carry enhancer elements for these two phenotypes. Finally, we speculate on the striking observation that some of the cis-regulatory regions of nonA appear to be embedded within the coding regions of dGpi1.
SINE Insertions in Cladistic Analyses and the Phylogenetic Affiliations of Tarsius bancanus to Other Primates
Authors: Schmitz Jürgen , Ohme Martina , Zischler Hans
Published: April 2021

Transpositions of Alu sequences, representing the most abundant primate short interspersed elements (SINE), were evaluated as molecular cladistic markers to analyze the phylogenetic affiliations among the primate infraorders. Altogether 118 human loci, containing intronic Alu elements, were PCR analyzed for the presence of Alu sequences at orthologous sites in each of two strepsirhine, New World and Old World monkey species, Tarsius bancanus, and a nonprimate outgroup. Fourteen size-polymorphic amplification patterns exhibited longer fragments for the anthropoids (New World and Old World monkeys) and T. bancanus whereas shorter fragments were detected for the strepsirhines and the outgroup. From these, subsequent sequence analyses revealed three Alu transpositions, which can be regarded as shared derived molecular characters linking tarsiers and anthropoid primates. Concerning the other loci, scenarios are represented in which different SINE transpositions occurred independently in the same intron on the lineages leading both to the common ancestor of anthropoids and to T. bancanus, albeit at different nucleotide positions. Our results demonstrate the efficiency and possible pitfalls of SINE transpositions used as molecular cladistic markers in tracing back a divergence point in primate evolution over 40 million years old. The three Alu insertions characterized underpin the monophyly of haplorhine primates (Anthropoidea and Tarsioidea) from a novel perspective.
Functional Dissection of the cis-Acting Sequences of the Arabidopsis Transposable Element Tag1 Reveals Dissimilar Subterminal Sequence and Minimal Spacing Requirements for Transposition
Authors: Liu Dong , Mack Alyson , Wang Rongchen , Galli Mary , Belk Jason , Ketpura Nan I , Crawford Nigel M
Published: April 2021

The Arabidopsis transposon Tag1 has an unusual subterminal structure containing four sets of dissimilar repeats: one set near the 5′ end and three near the 3′ end. To determine sequence requirements for efficient and regulated transposition, deletion derivatives of Tag1 were tested in Arabidopsis plants. These tests showed that a 98-bp 5′ fragment containing the 22-bp inverted repeat and four copies of the AAACCX (X = C, A, G) 5′ subterminal repeat is sufficient for transposition while a 52-bp 5′ fragment containing only one copy of the subterminal repeat is not. At the 3′ end, a 109-bp fragment containing four copies of the most 3′ repeat TGACCC, but not a 55-bp fragment, which has no copies of the subterminal repeats, is sufficient for transposition. The 5′ and 3′ end fragments are not functionally interchangeable and require an internal spacer DNA of minimal length between 238 and 325 bp to be active. Elements with these minimal requirements show transposition rates and developmental control of excision that are comparable to the autonomous Tag1 element. Last, a DNA-binding activity that interacts with the 3′ 109-bp fragment but not the 5′ 98-bp fragment of Tag1 was found in nuclear extracts of Arabidopsis plants devoid of Tag1.
Optimal Marker-Assisted Selection to Increase the Effective Size of Small Populations
Authors: Wang Jinliang
Published: April 2021

An approach to the optimal utilization of marker and pedigree information in minimizing the rates of inbreeding and genetic drift at the average locus of the genome (not just the marked loci) in a small diploid population is proposed, and its efficiency is investigated by stochastic simulations. The approach is based on estimating the expected pedigree of each chromosome by using marker and individual pedigree information and minimizing the average coancestry of selected chromosomes by quadratic integer programming. It is shown that the approach is much more effective and much less computer demanding in implementation than previous ones. For pigs with 10 offspring per mother genotyped for two markers (each with four alleles at equal initial frequency) per chromosome of 100 cM, the approach can increase the average effective size for the whole genome by ∼40 and 55% if mating ratios (the number of females mated with a male) are 3 and 12, respectively, compared with the corresponding values obtained by optimizing between-family selection using pedigree information only. The efficiency of the marker-assisted selection method increases with increasing amount of marker information (number of markers per chromosome, heterozygosity per marker) and family size, but decreases with increasing genome size. For less prolific species, the approach is still effective if the mating ratio is large so that a high marker-assisted selection pressure on the rarer sex can be maintained.
The seismic broad-band signature of high-speed trains running on viaducts
Authors: Liu Yujin , Yue Yubo , Luo Yi , Li Youming
Published: April 2021

The high-speed train (HST) generates strong ground vibrations when it runs on the railroad. However, little attention has been paid to the theory of far-field propagation of the HST-induced ground vibrations. Here, we derive two analytical formulae for the HST-induced seismic wavefields under the far-field approximation. In particular, we analyse the seismic wavefields in the cases when the HST runs on a track built on the ground and on the viaduct, respectively. We find that the vibrations generated by the HST running on the ground decay exponentially, whereas the HST running on the viaduct can generate broad-band seismic waves that can penetrate deep into the Earth. The derived formulae have been validated by the far-field observations in the field. Numerical results suggest that the ground vibrations generated by the HST, when running on the viaduct, could be utilized as a powerful, economic and repeatable source to image and monitor subsurface structures.
Frequency-dependent anisotropy in porous rocks with aligned cracks containing compressible fluid–a model based on poroelastic spring condition and exact solution of scattering by a circular crack at oblique incidence
Authors: Song Yongjia , Wang Jun , Hu Hengshan , Han Bo
Published: April 2021

Thorough understanding of seismic signatures in cracked rocks is essential to estimate rock physical properties. Wave-induced fluid flow (or diffusion), scattering and Biot's global flow are three major mechanisms in controlling frequency-dependent attenuation and dispersion. To shed light on how those mechanisms and their interference affect the anisotropic features in cracked porous rocks, we develop an analytic model to estimate the angle-dependent attenuation and dispersion in such media. The most noteworthy feature of the model is that it is developed upon the exact solution of the problem of elastic wave scattered by a crack at oblique incidence. In particular, the poroelastic spring condition is applied to describe the influences of crack thickness and crack-filling fluid elasticity on wave scattering. Regardless of its complexity, we have showed that the model agrees with many benchmark theories under corresponding conditions, demonstrating its reasonability. It is found that the key factors that dominate anisotropic attenuation and dispersion are different in separating frequency regimes. At diffusion-dominated frequencies, the frequency-dependent anisotropic properties are mainly determined by the normal stress on the crack faces. In contrast, in Rayleigh scattering regime, they are greatly determined by the applied shear stress. At higher frequencies (Mie scattering regime), affected by the wave reflections between the crack edges, the frequency-dependent anisotropy becomes complex. The angle-dependent velocity can largely deviate from elliptic-shaped profile. As a result, the material properties cannot be described within the framework of the transversely isotropic medium model. Moreover, it is found that the attenuation is sensitive to the fluid compressibility and crack thickness, showing evidences that it is possible to invert fluid saturation and permeability from seismic attenuation. We also conclude that using a simple linear superposition of the attenuations due to wave-induced fluid flow and elastic scattering from their corresponding equivalent medium models will leads to an overestimation of the total attenuation. Our results demonstrate it is necessary to account for the mechanism interference to allow for an adequate estimation of the intrinsic attenuation of cracked porous rocks.
Predicting COVID-19 health behaviour initiation, consistency, interruptions and discontinuation among social media users in Nigeria
Authors: Oyeoku Eke Kalu , Talabi Felix Olajide , Oloyede David , Boluwatife Aiyesimoju Ayodeji , Gever Verlumun Celestine , Ebere Ibe
Published: April 2021

Literature on the predictors of health behaviour initiation, interruption, consistency and discontinuation is scarce. This study sought to fill this gap by suggesting a model that takes into account these variables. Using the structural equation modelling, we surveyed 470 social media users in Nigeria and found that perceived vulnerability, perceived seriousness; benefits to action, self-efficacy and cues to action significantly predict health behaviour initiation. Also, the predictors of health interruption were found to be perceived vulnerability, perceived seriousness, benefits to action, challenges to action and perceived realness. The predictors of health behaviour consistency were found to be perceived vulnerability, perceived seriousness, benefits to action, perceived realness, self-efficacy and cues to action. Finally, the predictors of health behaviour discontinuation were found to be perceived vulnerability, perceived seriousness, perception on realness, behaviour fatigue and behaviour discomfort. We explored the implication of these results on health promotion and made suggestions for further studies.
Human adaptation, demography and cattle domestication: an overview of the complexity of lactase persistence in Africa
Authors: Campbell Michael C , Ranciaro Alessia
Published: April 2021

Lactase persistence (LP) is a genetically-determined trait that is prevalent in African, European and Arab populations with a tradition of animal herding and milk consumption. To date, genetic analyses have identified several common variants that are associated with LP. Furthermore, data have indicated that these functional alleles likely have been maintained in pastoralist populations due to the action of recent selection, exemplifying the ongoing evolution of anatomically modern humans. Additionally, demographic history has also played a role in the geographic distribution of LP and associated alleles in Africa. In particular, the migration of ancestral herders and their subsequent admixture with local populations were integral to the spread of LP alleles and the culture of pastoralism across the continent. The timing of these demographic events was often correlated with known major environmental changes and/or the ability of domesticated cattle to resist/avoid infectious diseases. This review summarizes recent advances in our understanding of the genetic basis and evolutionary history of LP, as well as the factors that influenced the origin and spread of pastoralism in Africa.
Is the UN Committee on the Rights of the Child Doing Enough to Protect the Rights of LGBT Children and Children with Same-Sex Parents?
Authors: Gerber Paula , Timoshanko Aaron
Published: April 2021

Children often face discrimination, bullying and even violence because of their sexual orientation or gender identity, as do children raised by parents who are lesbian, gay, bisexual or transgender (LGBT). This article considers what the UN Committee on the Rights of the Child is doing to protect the rights of LGBT children and children with LGBT parents. To make such an assessment, this article critically analyses the Committee’s Concluding Observations over a 10-year period, its General Comments and its Views on Individual Communications. The conclusion reached is that while the Committee has made encouraging progress in recent years when it comes to addressing LGBT related issues, there is still room for improvement in the way the Committee seeks to protect children from discrimination on the basis of sexual orientation and gender identity.
Ely in New Zealand
Authors: Geiringer Claudia
Published: April 2021

John Hart Ely’s representation-reinforcing theory of the US Constitution had a significant impact on the drafting of the New Zealand Bill of Rights Act 1990. This short article begins by recapping briefly the pathway by which that influence occurred. It then expands on earlier accounts in two ways. The first is to suggest that Ely’s influence in New Zealand illustrates the significance of American postgraduate legal education programs as a vector for the migration of constitutional ideas (although the causal relationship in this case is neither straightforward nor direct). The second is to confront more explicitly a nagging question raised by earlier scholarship: to what extent was it Ely specifically (rather than US process theories more generally) that influenced the New Zealand experience? The article suggests that, at very least, Ely’s work acted as the conduit by which the ideas underlying American process theory were transmitted into the New Zealand text. Although it is inevitably somewhat speculative, the article also suggests that it is unlikely that, in the absence of Ely, the drafters of the N.Z. Bill of Rights would have pursued a process-perfecting strategy with quite the same vigilance and systematicity.