bluuebunny/crossref_metadata_2025 huggingface dataset:
Bark-dwelling methanotrophic bacteria decrease methane emissions from trees
Authors: Jeffrey Luke C. , Maher Damien T. , Chiri Eleonora , Leung Pok Man , Nauer Philipp A. , Arndt Stefan K. , Tait Douglas R. , Greening Chris , Johnston Scott G.
Published: April 2021

Tree stems are an important and unconstrained source of methane, yet it is uncertain whether internal microbial controls (i.e. methanotrophy) within tree bark may reduce methane emissions. Here we demonstrate that unique microbial communities dominated by methane-oxidising bacteria (MOB) dwell within bark of Melaleuca quinquenervia, a common, invasive and globally distributed lowland species. In laboratory incubations, methane-inoculated M. quinquenervia bark mediated methane consumption (up to 96.3 µmol m−2 bark d−1) and reveal distinct isotopic δ13C-CH4 enrichment characteristic of MOB. Molecular analysis indicates unique microbial communities reside within the bark, with MOB primarily from the genus Methylomonas comprising up to 25 % of the total microbial community. Methanotroph abundance was linearly correlated to methane uptake rates (R2 = 0.76, p = 0.006). Finally, field-based methane oxidation inhibition experiments demonstrate that bark-dwelling MOB reduce methane emissions by 36 ± 5 %. These multiple complementary lines of evidence indicate that bark-dwelling MOB represent a potentially significant methane sink, and an important frontier for further research.
A prevalent and culturable microbiota links ecological balance to clinical stability of the human lung after transplantation
Authors: Das Sudip , Bernasconi Eric , Koutsokera Angela , Wurlod Daniel-Adrien , Tripathi Vishwachi , Bonilla-Rosso Germán , Aubert John-David , Derkenne Marie-France , Mercier Louis , Pattaroni Céline , Rapin Alexis , von Garnier Christophe , Marsland Benjamin J. , Engel Philipp , Nicod Laurent P.
Published: April 2021

There is accumulating evidence that the lower airway microbiota impacts lung health. However, the link between microbial community composition and lung homeostasis remains elusive. We combine amplicon sequencing and bacterial culturing to characterize the viable bacterial community in 234 longitudinal bronchoalveolar lavage samples from 64 lung transplant recipients and establish links to viral loads, host gene expression, lung function, and transplant health. We find that the lung microbiota post-transplant can be categorized into four distinct compositional states, ‘pneumotypes’. The predominant ‘balanced’ pneumotype is characterized by a diverse bacterial community with moderate viral loads, and host gene expression profiles suggesting immune tolerance. The other three pneumotypes are characterized by being either microbiota-depleted, or dominated by potential pathogens, and are linked to increased immune activity, lower respiratory function, and increased risks of infection and rejection. Collectively, our findings establish a link between the lung microbial ecosystem, human lung function, and clinical stability post-transplant.
Indispensable role of Galectin-3 in promoting quiescence of hematopoietic stem cells
Authors: Jia Weizhen , Kong Lingyu , Kidoya Hiroyasu , Naito Hisamichi , Muramatsu Fumitaka , Hayashi Yumiko , Hsieh Han-Yun , Yamakawa Daishi , Hsu Daniel K. , Liu Fu-Tong , Takakura Nobuyuki
Published: April 2021

Hematopoietic stem cells (HSCs) in adult bone marrow (BM) are usually maintained in a state of quiescence. The cellular mechanism coordinating the balance between HSC quiescence and differentiation is not fully understood. Here, we report that galactose-binding lectin-3 (galectin-3; Gal-3) is upregulated by Tie2 or Mpl activation to maintain quiescence. Conditional overexpression of Gal-3 in mouse HSCs under the transcriptional control of Tie2 or Vav1 promoters (Gal-3 Tg) causes cell cycle retardation via induction of p21. Conversely, the cell cycle of long-term repopulating HSCs (LT-HSCs) in Gal-3-deficient (Gal-3-/-) mice is accelerated, resulting in their exhaustion. Mechanistically, Gal-3 regulates p21 transcription by forming a complex with Sp1, thus blocking cell cycle entry. These results demonstrate that Gal-3 is a negative regulator of cell-cycling in HSCs and plays a crucial role in adult hematopoiesis to prevent HSC exhaustion.
Creating enzymes and self-sufficient cells for biosynthesis of the non-natural cofactor nicotinamide cytosine dinucleotide
Authors: Wang Xueying , Feng Yanbin , Guo Xiaojia , Wang Qian , Ning Siyang , Li Qing , Wang Junting , Wang Lei , Zhao Zongbao K.
Published: April 2021

Nicotinamide adenine dinucleotide (NAD) and its reduced form are indispensable cofactors in life. Diverse NAD mimics have been developed for applications in chemical and biological sciences. Nicotinamide cytosine dinucleotide (NCD) has emerged as a non-natural cofactor to mediate redox transformations, while cells are fed with chemically synthesized NCD. Here, we create NCD synthetase (NcdS) by reprograming the substrate binding pockets of nicotinic acid mononucleotide (NaMN) adenylyltransferase to favor cytidine triphosphate and nicotinamide mononucleotide over their regular substrates ATP and NaMN, respectively. Overexpression of NcdS alone in the model host Escherichia coli facilitated intracellular production of NCD, and higher NCD levels up to 5.0 mM were achieved upon further pathway regulation. Finally, the non-natural cofactor self-sufficiency was confirmed by mediating an NCD-linked metabolic circuit to convert L-malate into D-lactate. NcdS together with NCD-linked enzymes offer unique tools and opportunities for intriguing studies in chemical biology and synthetic biology.
Discovery of fungal oligosaccharide-oxidising flavo-enzymes with previously unknown substrates, redox-activity profiles and interplay with LPMOs
Authors: Haddad Momeni Majid , Fredslund Folmer , Bissaro Bastien , Raji Olanrewaju , Vuong Thu V. , Meier Sebastian , Nielsen Tine Sofie , Lombard Vincent , Guigliarelli Bruno , Biaso Frédéric , Haon Mireille , Grisel Sacha , Henrissat Bernard , Welner Ditte Hededam , Master Emma R. , Berrin Jean-Guy , Abou Hachem Maher
Published: April 2021

Oxidative plant cell-wall processing enzymes are of great importance in biology and biotechnology. Yet, our insight into the functional interplay amongst such oxidative enzymes remains limited. Here, a phylogenetic analysis of the auxiliary activity 7 family (AA7), currently harbouring oligosaccharide flavo-oxidases, reveals a striking abundance of AA7-genes in phytopathogenic fungi and Oomycetes. Expression of five fungal enzymes, including three from unexplored clades, expands the AA7-substrate range and unveils a cellooligosaccharide dehydrogenase activity, previously unknown within AA7. Sequence and structural analyses identify unique signatures distinguishing the strict dehydrogenase clade from canonical AA7 oxidases. The discovered dehydrogenase directly is able to transfer electrons to an AA9 lytic polysaccharide monooxygenase (LPMO) and fuel cellulose degradation by LPMOs without exogenous reductants. The expansion of redox-profiles and substrate range highlights the functional diversity within AA7 and sets the stage for harnessing AA7 dehydrogenases to fine-tune LPMO activity in biotechnological conversion of plant feedstocks.
Ocean surface energy balance allows a constraint on the sensitivity of precipitation to global warming
Authors: Wang Wei , Chakraborty T. C. , Xiao Wei , Lee Xuhui
Published: April 2021

Climate models generally predict higher precipitation in a future warmer climate. Whether the precipitation intensification occurred in response to historical warming continues to be a subject of debate. Here, using observations of the ocean surface energy balance as a hydrological constraint, we find that historical warming intensified precipitation at a rate of 0.68 ± 0.51% K−1, which is slightly higher than the multi-model mean calculation for the historical climate (0.38 ± 1.18% K−1). The reduction in ocean surface albedo associated with melting of sea ice is a positive contributor to the precipitation temperature sensitivity. On the other hand, the observed increase in ocean heat storage weakens the historical precipitation. In this surface energy balance framework, the incident shortwave radiation at the ocean surface and the ocean heat storage exert a dominant control on the precipitation temperature sensitivity, explaining 91% of the inter-model spread and the spread across climate scenarios in the Intergovernmental Panel on Climate Change Fifth Assessment Report.
Varying demands for cognitive control reveals shared neural processes supporting semantic and episodic memory retrieval
Authors: Vatansever Deniz , Smallwood Jonathan , Jefferies Elizabeth
Published: April 2021

The categorisation of long-term memory into semantic and episodic systems has been an influential catalyst for research on human memory organisation. However, the impact of variable cognitive control demands on this classical distinction remains to be elucidated. Across two independent experiments, here we directly compare neural processes for the controlled versus automatic retrieval of semantic and episodic memory. In a multi-session functional magnetic resonance imaging experiment, we first identify a common cluster of cortical activity centred on the left inferior frontal gyrus and anterior insular cortex for the retrieval of both weakly-associated semantic and weakly-encoded episodic memory traces. In an independent large-scale individual difference study, we further reveal a common neural circuitry in which reduced functional interaction between the identified cluster and ventromedial prefrontal cortex, a default mode network hub, is linked to better performance across both memory types. Our results provide evidence for shared neural processes supporting the controlled retrieval of information from functionally distinct long-term memory systems.
IL-33 expression in response to SARS-CoV-2 correlates with seropositivity in COVID-19 convalescent individuals
Authors: Stanczak Michal A. , Sanin David E. , Apostolova Petya , Nerz Gabriele , Lampaki Dimitrios , Hofmann Maike , Steinmann Daniel , Krohn-Grimberghe Marvin , Thimme Robert , Mittler Gerhard , Waller Cornelius F. , Pearce Edward J. , Pearce Erika L.
Published: April 2021

Our understanding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is still developing. We perform an observational study to investigate seroprevalence and immune responses in subjects professionally exposed to SARS-CoV-2 and their family members (155 individuals; ages 5–79 years). Seropositivity for SARS-CoV-2 Spike glycoprotein aligns with PCR results that confirm the previous infection. Anti-Spike IgG/IgM titers remain high 60 days post-infection and do not strongly associate with symptoms, except for fever. We analyze PBMCs from a subset of seropositive and seronegative adults. TLR7 agonist-activation reveals an increased population of IL-6+TNF-IL-1β+ monocytes, while SARS-CoV-2 peptide stimulation elicits IL-33, IL-6, IFNa2, and IL-23 expression in seropositive individuals. IL-33 correlates with CD4+ T cell activation in PBMCs from convalescent subjects and is likely due to T cell-mediated effects on IL-33-producing cells. IL-33 is associated with pulmonary infection and chronic diseases like asthma and COPD, but its role in COVID-19 is unknown. Analysis of published scRNAseq data of bronchoalveolar lavage fluid (BALF) from patients with mild to severe COVID-19 reveals a population of IL-33-producing cells that increases with the disease. Together these findings show that IL-33 production is linked to SARS-CoV-2 infection and warrant further investigation of IL-33 in COVID-19 pathogenesis and immunity.
Author Correction: Network-based modeling of drug effects on disease module in systemic sclerosis
Authors: Kim Ki-Jo , Moon Su-Jin , Park Kyung-Su , Tagkopoulos Ilias
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Comparison of oncologic and functional outcomes between radical nephroureterectomy and segmental ureterectomy for upper urinary tract urothelial carcinoma
Authors: Kim Tae Heon , Lee Chung Un , Kang Minyong , Jeon Hwang Gyun , Jeong Byong Chang , Seo Seong Il , Jeon Seong Soo , Lee Hyun Moo , Sung Hyun Hwan
Published: April 2021

This study aims to compare oncologic and functional outcomes after radical nephroureterectomy (RNU) and segmental ureterectomy (SU) in patients with upper urinary tract urothelial carcinoma (UTUC). We retrospectively collected data on patients who underwent either RNU or SU of UTUC. Propensity score matching was performed among 394 cases to yield a final cohort of 40 RNU and 40 SU cases. Kaplan–Meier analysis and the log-rank test were used to compare overall survival (OS), cancer-specific survival (CSS), progression-free survival (PFS), and intravesical recurrence-free survival (IVRFS) between the groups. We also compared the change in postoperative estimated glomerular filtration rate (eGFR). There was no significant difference in terms of CSS, PFS, and IVRFS between the RNU and SU groups, but the RNU group had a better OS than the SU group (p = 0.032). Postoperative eGFR was better preserved in the SU group than in the RNU group (p < 0.001). SU provides comparable CSS, PFS, and IVRFS for patients with UTUC compared to RNU, even in patients with advanced-stage and/or high-grade cancer. Further, SU achieves better preservation of renal function.
Author Correction: CMR-derived ECVs vary with myocardial region and associate with the regional wall thickness
Authors: Su Mao-Yuan , Hou Kuei-Yuan , Liu Ming-Hung , Lin Tien-Min , Juang Jyh-Ming Jimmy , Lin Lian-Yu , Wu Cho-Kai , Yu Hsi-Yu , Yang Shun-Chung , Huang Yu-Sen , Niisato Emi , Chang Yeun-Chung
Published: April 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Highly sensitive detection of DNA methyltransferase activity and its inhibitor screening by coupling fluorescence correlation spectroscopy with polystyrene polymer dots
Authors: Huang Yuyang , Deng Liyun , Su Di , Huang Xiangyi , Ren Jicun
Published: April 2021

A sensitive method based on fluorescence correlation spectroscopy and polymer dots for the detection of DNA methyltransferase activity without separation.
Cobalt encapsulated in bamboo-like N-doped carbon nanotubes for highly sensitive electroanalysis of Pb(ii): enhancement based on adsorption and catalysis
Authors: Xu Qian-Qian , Xia Xu , Zhu Min , Xu Li-Hao , Zhang Yong-Xing , Li Shan-Shan
Published: April 2021

By combining the adsorption ability of N-CNTs with the catalysis of Co NPs to form Co/N-CNTs, the newly constructed Co/N-CNTs reveal a significantly improved electroanalytical performance towards Pb(ii) with an impressive sensitivity of 69.74 μA μM−1.
Highly efficient methyl orange adsorption by UV-012, a new crystalline Co(ii) MOF
Authors: Ramírez Daniel J. , Alfonso Herrera Luis A. , Colorado-Peralta Raúl , Rodríguez Rodolfo Peña , Camarillo Reyes P. K. , Chiñas Lidia Elena , Sánchez Mario , Rivera José María
Published: April 2021

This work presents three scientific contributions: the new metal organic framework (UV-012) crystal structure, the evaluation of this new material for dye adsorption and a new mechanism that explains the excellent and selective anionic dye adsorption by this material.
Sequential assignment of NMR spectra of peptides at natural isotopic abundance with zero- and ultra-low-field total correlation spectroscopy (ZULF-TOCSY)
Authors: Kiryutin Alexey S. , Zhukov Ivan V. , Ferrage Fabien , Bodenhausen Geoffrey , Yurkovskaya Alexandra V. , Ivanov Konstantin L.
Published: April 2021

A novel method dubbed ZULF-TOCSY results from the combination of Zero and Ultra-Low Field (ZULF) with high-field, high-resolution NMR, leading to a generalization of the concept of total correlation spectroscopy (TOCSY).
Formation of water-in-oil microemulsions within a hydrophobic deep eutectic solvent
Authors: Dhingra Divya , Behera Kamalakanta , Bhawna  , Pandey Siddharth
Published: April 2021

The neoteric, non-toxic, and inexpensive hydrophobic deep eutectic solvents as potential alternative to toxic organic solvents as oil phase in water-in-oil microemulsions.
Radially resolved optical emission spectral imaging study of an atmospheric pressure μDBD jet for elucidating the effect of sample surface material on the underlying mechanisms
Authors: Shi Songyue , Finch Kevin , Gamez Gerardo
Published: April 2021

Maps of excited plasma species and temperatures reveal the sample surface impact on the upstream APPJ energy transfer pathways.
Phase stability of monolayer Si1−xGexalloys with a Dirac cone
Authors: Ma Xiaoyang , Yang Tong , Li Dechun , Feng Yuanping
Published: April 2021

Si1−xGexalloys can be stabilized and thereby form solid solutions at high temperature (above 550 K). By constructing special quasi-random structures (SQSs), the alloy structures are found to possess a robust Dirac cone against composition variation.
Binding of tyrosine kinase inhibitor to epidermal growth factor receptor: surface-enhanced infrared absorption microscopy reveals subtle protein secondary structure variations
Authors: Zucchiatti Paolo , Birarda Giovanni , Cerea Andrea , Semrau Marta S. , Hubarevich Aliaksandr , Storici Paola , De Angelis Francesco , Toma Andrea , Vaccari Lisa
Published: April 2021

Mid-IR plasmonic device for SEIRA microscopy allowed to reveal the subtle conformational changes associated with the binding of Lapatinin inhibitor to the kinase domain of EGFR receptor, a well-known driver of tumorigenesis in pathological settings.
Combining vancomycin-modified gold nanorod arrays and colloidal nanoparticles as a sandwich model for the discrimination of Gram-positive bacteria and their detection via surface-enhanced Raman spectroscopy (SERS)
Authors: Norouz Dizaji Araz , Simsek Ozek Nihal , Aysin Ferhunde , Calis Ayfer , Yilmaz Asli , Yilmaz Mehmet
Published: April 2021

This study reports the development of a highly sensitive antibiotic-based discrimination and sensor platform for the detection of Gram-positive bacteria through surface-enhanced Raman spectroscopy (SERS).
Base promoted gem-difluoroolefination of alkyl triflones
Authors: Yang Ren-Yin , Wang Hui , Xu Bo
Published: April 2021

A new synthesis of gem-difluoroalkenes from readily available alkyl triflones and difluorocarbene precursors such as TMSCF2Br has been reported.
Superphane: a new lantern-like receptor for encapsulation of a water dimer
Authors: Li Aimin , Xiong Shenglun , Zhou Wei , Zhai Huijuan , Liu Yuanchu , He Qing
Published: April 2021

This work describes the one-pot synthesis of a superphane-based supramolecular receptor and its encapsulation of a water dimer.
Mitochondria targeted near-infrared chemodosimeter for upconversion luminescence bioimaging of hypoxia
Authors: Yu Hui , Sun Wanlu , Tiemuer Aliya , Zhang Yuanyuan , Wang Hai-Yan , Liu Yi
Published: April 2021

A novel frequency upconversion luminescence chemodosimeter is capable of specially targeting mitochondria and monitoring tumor hypoxia in vivo.
Interrogating biomineralization one amino acid at a time: amplification of mutational effects in protein-aided titania morphogenesis through reaction-diffusion control
Authors: Pushpavanam Karthik , Hellner Brittney , Baneyx François
Published: April 2021

A reaction-diffusion biomineralization chamber operated with solid-binding proteins produces unique titania morphologies and magnifies the otherwise subtle effects of single or double mutations in the protein's materials-binding segment.
Origin of the Ir–Si bond shortening in Ir–NSiN complexes
Authors: García-Orduña Pilar , Fernández Israel , Oro Luis A. , Fernández-Alvarez Francisco J.
Published: April 2021

Ionic contributions are key for the Ir–Si bond shortening !!.
A metal–organic framework-derived Zn1−xCdxS/CdS heterojunction for efficient visible light-driven photocatalytic hydrogen production
Authors: Bai Tianyu , Shi Xiaofan , Liu Ming , Huang Hui , Yu Mei-Hui , Zhang Jijie , Bu Xian-He
Published: April 2021

The zeolitic imidazolate framework-8 (ZIF-8) was used as a precursor to prepare ZnCdS-based quantum dot heterojunctions to achieve the visible light-driven water splitting hydrogen production efficiently.
High-performance all-small-molecule organic solar cells without interlayers
Authors: Sun Rui , Wu Yao , Guo Jie , Wang Yuheng , Qin Fei , Shen Bingxiu , Li Donghui , Wang Tao , Li Yaowen , Zhou Yinhua , Lu Guanghao , Li Yongfang , Min Jie
Published: April 2021

A universal two-step solvent treatment strategy has been proved to be effective for constructing high performance all-small-molecule solar cells without interlayers.
Carbon-coated WS2 nanosheets supported on carbon nanofibers for high-rate potassium-ion capacitors
Authors: Geng Shitao , Zhou Tong , Jia Minyu , Shen Xiangyan , Gao Peibo , Tian Shuang , Zhou Pengfei , Liu Bo , Zhou Jin , Zhuo Shuping , Li Feng
Published: April 2021

A freestanding anode of carbon-coated WS2 nanosheets supported on carbon nanofibers (C-WS2@CNFs) is designed for fabricating high-rate potassium-ion capacitors.
The application of machine learning for predicting the methane uptake and working capacity of MOFs
Authors: Suyetin Mikhail
Published: April 2021

Multiple linear regression as a part of machine learning is employed to develop equations to predict the methane uptake and working capacity of MOFs. Only three geometrical descriptors are used in the equations: surface area, pore volume and density.
The photoreduction of selenite and selenate on the surface of few layer black phosphorus and a UiO-66 p–n junction heterostructure
Authors: Machabaphala Kamogelo Martha , Hlekelele Lerato , Dlamini Langelihle Nsikayezwe
Published: April 2021

The synthesis and characterization of a type-II heterojunction consisting of UiO-66 and few-layer black phosphorus with superior selenium oxyanion photo-reduction efficiency.
IL-4 rs2243250 polymorphism associated with susceptibility to allergic rhinitis: a meta-analysis
Authors: Jiang Feifei , Yan Aihui
Published: April 2021

Objective: The relationship between IL-4 rs2243250 polymorphism and the risk of allergic rhinitis is not clear at present. The present study aims to evaluate the exact association between IL-4 rs2243250 polymorphism and susceptibility to allergic rhinitis by a meta-analysis.

Methods: The studies about IL-4 rs2243250 polymorphism associated with susceptibility to allergic rhinitis were searched using PubMed, Excerpta Medica Database (EMBASE), Web of Science, Cochrane Library, China National Knowledge Infrastructure (CNKI) and China Wanfang databases. The last search time was on March 1, 2021. Data analysis was performed using Stata 15.0 software.

Results: Nine documents were enrolled, from which 1709 patients with allergic rhinitis were included. Among them, six genotype frequencies in the control group conformed to Hardy–Weinberg Equilibrium (HWE). The meta-analysis of all included studies showed significant heterogeneity of each gene model. After omitting the studies whose genotype frequency in the control group did not meet the requirements of HWE, no significant heterogeneity was found in each gene model. The meta-analysis results of the control group genotypes in line with the HWE showed statistically significant differences in the pooled odds ratio (OR) of allele model (T vs. C), recessive model (TT vs. TC+CC) and homozygous model (TT vs. CC), which were 1.19 (95%CI: 1.04–1.35), 1.28 (95%CI: 1.06–1.55) and 1.56 (95%CI: 1.13–2.17), respectively. No statistically significant difference was observed in dominant and heterozygous genetic models.

Conclusion: IL-4 rs2243250 single nucleotide polymorphism associated with susceptibility to allergic rhinitis, allele T and genotype TT could increase the risk of allergic rhinitis.
RNA:DNA triple helices: from peculiar structures to pervasive chromatin regulators
Authors: Greifenstein Andreas Adam , Jo SoYoung , Bierhoff Holger
Published: April 2021

The genomes of complex eukaryotes largely contain non-protein-coding DNA, which is pervasively transcribed into a plethora of non-coding RNAs (ncRNAs). The functional importance of many of these ncRNAs has been investigated in the last two decades, revealing their crucial and multifaceted roles in chromatin regulation. A common mode of action of ncRNAs is the recruitment of chromatin modifiers to specific regions in the genome. Whereas many ncRNA–protein interactions have been characterised in detail, binding of ncRNAs to their DNA target sites is much less understood. Recently developed RNA-centric methods have mapped the genome-wide distribution of ncRNAs, however, how ncRNAs achieve locus-specificity remains mainly unresolved. In terms of direct RNA–DNA interactions, two kinds of triple-stranded structures can be formed: R-loops consisting of an RNA:DNA hybrid and a looped out DNA strand, and RNA:DNA triple helices (triplexes), in which the RNA binds to the major groove of the DNA double helix by sequence-specific Hoogsteen base pairing. In this essay, we will review the current knowledge about RNA:DNA triplexes, summarising triplex formation rules, detection methods, and ncRNAs reported to engage in triplexes. While the functional characterisation of RNA:DNA triplexes is still anecdotal, recent advances in high-throughput and computational analyses indicate their widespread distribution in the genome. Thus, we are witnessing a paradigm shift in the appreciation of RNA:DNA triplexes, away from exotic structures towards a prominent mode of ncRNA–chromatin interactions.
Energy and spectral efficient relay selection and resource allocation in mobile multi‐hop device to device communications
Authors: Selmi Sawsan , Bouallègue Ridha
Published: April 2021

The expansion of smart devices and throughput requirements have triggered the integration of multi‐hop Device to Device (D2D) underlay the fifth generation (5G) network. This new paradigm has extended the coverage area and enabled ultra‐low latency and cost‐per‐bit communications. While the previous 3GPP releases address only the coverage problem via two‐hop D2D, this paper focuses on multi‐hop D2D defined in 3GPP release 15 and beyond. It proposes a distributed relay selection and resource allocation algorithm based on a mixed strategy game and a novel amplify and forward factor. The proposed schema maximizes the joint spectral and energy efficiency. Besides, it determines the optimal amount of data and energy transferred by each device. The efficiency of this approach against other state‐of‐the‐art solutions is evaluated and verified through computer simulations.
Coconut trees detection and segmentation in aerial imagery using mask region‐based convolution neural network
Authors: Iqbal Muhammad Shakaib , Ali Hazrat , Tran Son N. , Iqbal Talha
Published: April 2021

Food resources face severe damages under extraordinary situations of catastrophes such as earthquakes, cyclones, and tsunamis. Under such scenarios, speedy assessment of food resources from agricultural land is critical as it supports aid activity in the disaster‐hit areas. In this article, a deep learning approach was presented for the detection and segmentation of coconut trees in aerial imagery provided through the AI competition organised by the World Bank in collaboration with OpenAerialMap and WeRobotics. Masked Region‐based Convolution Neural Network (Mask R‐CNN) approach was used for identification and segmentation of coconut trees. For the segmentation task, Mask R‐CNN model with ResNet50 and ResNet101 based architectures was used. Several experiments with different configuration parameters were performed and the best configuration for the detection of coconut trees with more than 90% confidence factor was reported. For the purpose of evaluation, Microsoft COCO dataset evaluation metric namely mean average precision (mAP) was used.An overall 91% mean average precision for coconut trees’ detection was achieved.
3D object recognition with a linear time‐varying system of overlay layers
Authors: Sohrabi Nasrabadi Mohammad , Safabakhsh Reza
Published: April 2021

Object recognition is a challenging task in computer vision with numerous applications. The challenge is in selecting appropriate robust features with tolerable computing costs. Feature learning attempts to solve the feature extraction problem through a learning process using various samples of the objects. This research proposes a two‐stage optimization framework to identify the structure of a first‐order linear non‐homogeneous difference equation which is a linear time‐varying system of overlay layers (LtvoL) that construct an image. The first stage consists of the determination of a finite set of impulses, called overlay layers, by the application of a genetic algorithm. The second stage defines the coefficients of the corresponding difference equation derived from L2 regularization. Classification of the test images is possible by a novel process exclusively designed for this model. Experiments on the Washington RGB‐D dataset and ETH‐80 show promising results which are comparable to those of state‐of‐the‐art methods for RGB‐D‐based object recognition.
A novel circularly polarized slotted substrate integrated waveguide antenna array for satellite applications
Authors: Eid Alla M. , Salama Amgad A. , Elkamchouchi Hassan M.
Published: April 2021

In this article, three novel slotted substrate integrated waveguide (SIW) antenna elements are demonstrated with different radiator configurations, namely, two arms Archimedean antenna, single‐arm spiral antenna (monofilar), and four concentric circular loops antenna. Additionally, their near, as well as far‐field characteristics, have been investigated. The two arms Archimedean spiral antenna has a superior radiation characteristic of 18% return loss bandwidth (RLBW), 12% boresight axial ratio bandwidth (ARBW), and five dBi directivity. Furthermore, a 1 × 10 slotted SIW travelling wave antenna array has been designed, fabricated, and measured. The performance of the proposed antenna array versus the last reported antenna was evaluated and the proposed antenna array performance is superior to that of the others. Moreover, the measurements of the proposed array have a good agreement with the simulation results in which, 35%, 13% RLBW, and ARBW, respectively, have been achieved. The directivity of the proposed antenna array is 14 dBi.
Collocated MIMO travelling wave SIW slot array antennas for millimetre waves
Authors: Ghalib Asim , Sharawi Mohammad S. , Mittra Raj , Attia Hussein , Shammim Atif
Published: April 2021

A novel four‐element collocated travelling wave substrate integrated waveguide (SIW) multiple‐input multiple‐output (MIMO) antenna covering millimetre wave (mm‐wave) bands (28–32 GHz) is presented. The antenna exhibits a matching bandwidth of more than 4 GHz and a measured gain of 15 dBi. The MIMO antenna elements are collocated, thus significantly reducing the size of the proposed design. To spatially isolate the beams (obtain lower correlation coefficient) of the MIMO antenna elements, the beams are oriented in different directions. The slots within each SIW array are designed to provide tilted beams, thus eliminating the need for a beam switching network. Four distinct beams are formed towards ±10° and ±30°. The dimension of the four‐element MIMO SIW design is 68 × 30.68 × 0.5 mm3. The proposed antenna has a high gain, compact size, simpler feeding and enhanced MIMO capability compared to other SIW antennas proposed in the literature.
Design of compact planar power divider with wideband bandpass response and high in‐band isolation
Authors: Wang Xuedao , Wang Jianpeng , Zhu Lei , Choi Wai‐Wa , Wu Wen
Published: April 2021

In this study, a compact planar power divider (PD) with wideband bandpass response is proposed based on a coupled three‐line filtering prototype. With two back‐to‐back microstrip feeding lines and a coplanar waveguide resonator located in the middle ground plane, the filtering structure is constructed. According to the synthesis approach, the proposed filtering structure can achieve an equal in‐band ripple response with three transmission poles and four out‐of‐band transmission zeros. In order to make the proposed PD inherit the designed filtering performance, one of the output lines in the filter network is modified to realize a 50 to 25 Ω impedance transformation in the passband first. Then, for good in‐band isolation and impedance matching at output ports, the modified output line is split into two separated lines by a slot so that a lumped resistor can be loaded at the ends of the two separated output lines. By properly setting the slot width and the resistance with guidance, high isolation level over an ultra‐wide passband is attained. For demonstration, three cases of the PDs with different bandwidths are designed on the basis of the corresponding filter designs. Finally, two bandpass PDs are fabricated and tested to verify the design concept.
Using length data to derive biological reference points for kiddi shrimp Parapenaeopsis stylifera (Milne Edwards, 1837) from the south-eastern Arabian Sea, India
Authors: Pillai Saraswathy Lakshmi , Maheswarudu Gidda , Baby Ponnathara Kandankoran , Radhakrishnan Madavan , Ragesh Nadakkal , Sreesanth Lakshmanan
Published: April 2021

Parapenaeopsis stylifera, a major commercial penaeid shrimp fishery resource in the Indian Ocean, has lacked adequate information on life history parameters for nearly two decades. In this study, growth and mortality parameters of P. stylifera from the southwest coast of India were estimated using length data and used to derive biological reference points for the species. The asymptotic length for females was L∞ = 131 mm; k = 1.1 y−1 and for males L∞ = 117 mm; k = 1.25 y−1. Mortality parameter estimates were Z = 4.42, M = 1.24, F = 3.18 y−1 and exploitation rate E = 0.72 for females; Z = 5.76, M = 1.39, F = 4.37 y−1 and E = 0.76 for males. Thomson and Bell yield biomass, Beverton and Holt yield per recruit, and relative yield per recruit models were applied to predict the stock status and length cohort analysis for estimating the stock size. The Beverton and Holt analysis gave Emax = 0.69 in females and 0.75 for males, which is below the Ecurrent values obtained for the sexes. The Thomson and Bell analysis indicated that if Fcurrent at which the yield is 121 460 t in females and in males 128 064 t is further increased, rise in yield will be modest. B/B0 and SB/SB0 at Fcurrent were 24% and 18% for females and 21% and 16% for males, respectively. Target reference point F0.1 and F0.5 at different levels of age at capture tc (0.5, 0.6, 0.7 and 0.8 yrs) was estimated by Beverton and Holt yield per recruit model. The outcome from these models forms integral inputs for multispecies/multigear tropical fisheries management. Parapenaeopsis stylifera is one of the inshore penaeid shrimp identified by the Marine Stewardship Council for certification from the region and, moreover, biological reference points are a prerequisite to assessment and management of tropical multispecies fisheries for ecosystem-based fisheries management.
Natural and economic effects of renewable energy sources in the developing countries: a case of Azerbaijan
Authors: Rzayeva Zhala , Guliyeva Aysel , Miriyeva Arzu
Published: April 2021

This paper focuses in the natural and economic effects of renewable energy sources in the developing countries using a case of Azerbaijan. Traditional fuel supplies dependent on gas, oil, and coal are highly useful for the development of a country’s economy. However, certain detrimental effects of these commodities on the environment have limited us to use these resources under clear cut-off points. As a result, we were able to turn our intuition into renewable energy sources. By using renewable energy sources, social, natural, and financial challenges can be ignored because these sources are considered harmless to the atmosphere, as there are little or virtually no fumes discharged, and toxic gases such as carbon dioxide, carbon monoxide, and sulfur dioxide. Renewable electricity would be a major advantage for power generation in the near future so we will reuse these assets to generate useful electricity. The paper discusses these and other issues with the implementation of renewable energy and assess the potentials of Azerbaijan in adapting this type of energy in the future.
Role of higher education in sustainable development of regions
Authors: Gardanova Zhanna , Nikitina Natalya , Grebennikova Veronika , Ilgov Vyacheslav
Published: April 2021

The role of higher educational institutions (HEIs) in sustainable regional development is becoming a subject of attention of researchers and policymakers. Apart from clear inputs such as sustainable education and promotion of renewable energy sources, HEIs can act as partners and consultancies for the local authorities helping them to embark on the path of sustainable economic and social growth. Our paper looks into the role of higher education in sustainable development of regions. We identify HEIs as the hubs of knowledge and know-how spill-overs as well as active players in industry-university connection. Our results confirm the importance of higher education in promoting the decarbonization of economy, helping the transition to the renewables and the creation of wider social acceptance of sustainable development.
The role of the university in achieving SDGs 4 and 7: a Ukrainian case
Authors: Artyukhov Artem , Volk Iurii , Vasylieva Tetyana , Lyeonov Serhiy
Published: April 2021

This article deals with the development of the university activities model to ensure the quality of education and technology transfer (SDG 4) and to create a successful background in achieving SDG 7. We conduct an analysis of the literature on the achievement of SDGs through governmental instruments of influence, as well as the creation of effective university model ensuring the education quality and technology transfer. In addition, we demonstrate the role of the government in financing higher education in Ukraine. We also present the evaluation of the popularity of educational programs related to energy efficiency and a “clean” environment in Ukrainian universities after the adoption of the 2030 Agenda for Sustainable Development. The indicators of the use of various energy types by Ukraine are assessed, and a comparative analysis of these indicators with the data for EU-28 is performed. Based on the data presented, conclusions are drawn about the need to improve the quality of university training and to activate the university technology transfer. Successful practical approaches that can be of use for different higher education institutions are outlined. A combined model of quality assurance and technology transfer at the university is presented. An algorithm for testing the model and assessing the technological level of readiness for implementation is developed. The presented chain “combined model – model testing algorithm – determination of the technological level of readiness” is also assessed from the point of view of socio-economic impact on the main stakeholders. The use of the combined model lays background for the university’s own sustainable development as a tool for achieving SDGs.
Sustainable spatial development: a story of Novosibirsk and Krasnoyarsk agglomerations
Authors: Usmanova Irina , Ligaeva Nadezhda , Kuznetsova Olga
Published: April 2021

Under the conditions of market-economic reforms that have been taking place in Russia over the past 30 years, the sectoral and territorial structure of the country’s economy has changed dramatically. The economy of some regions, that were successful during the Soviet times sagged and failed, while other regions experienced an actual economic take-off. This paper discusses the main aspects of the spatial organization of the Russian Federation and the development of the Novosibirsk and Krasnoyarsk agglomerations, which are the largest economic centers of Western and Eastern Siberia. To answer the main question of the study-whether thirty years of economic restructuring in the country could affect the leading position of Novosibirsk and make Krasnoyarsk the new regional leader of Siberia, the authors perform the comparative socio-economic analysis of both agglomerations.
Digital transformation of energy sector companies
Authors: Akberdina Victoria , Osmonova Ainur
Published: April 2021

Digital transformation is an ongoing process that is driven by the recent advances in digitalization as well as the development of information and communication technologies (ICT) that penetrate all socio-economic fields of everyday life and business. In this paper, we describe the digital transformation of energy companies. We show that successful transformation is based on skills, expertise and knowledge of the employees that need to be created and maintained. In addition, we show that digital competences become a key element in building capacities that are required for the digital transformation. This is of a particular importance for the energy companies that are experiencing major changes on the path of transition toward low-carbon economy and renewable energy.
Adaptive accumulation and diagnostic information systems of enterprises in energy and industry sectors
Authors: Sobchuk Valentyn , Barabash Oleg , Musienko Andriy , Svynchuk Olha
Published: April 2021

Our paper describes the methodology of an effective system construction based on information systems self-diagnosis using the case of Ukrainian enterprises in metallurgy, energy, and chemical industry. It describes the method of organization and implementation of self-diagnosis, mechanisms of detection, as well as the identification and localization of failed modules. The results formulate the criteria of sufficiency of efficiency of diagnostic information in the absence of restrictions on performance of elementary checks. Moreover, it yields the criterion of sufficiency of diagnostic information in the presence of restrictions on performance of elementary checks.
Primary parameters design method for distributed electric propulsion unmanned aerial vehicle
Authors: Ma Yiyuan , Zhang Wei , Zhang Xingyu , Zhang Xiaobin , Ma Yuelong , Guo Zhanpeng
Published: April 2021

Distributed electric propulsion technology brings new ideas to the design of unmanned aerial vehicle(UAV), such as improving aerodynamic efficiency and propulsive efficiency, and new concept of vertical/short takeoff and landing configurations. However, compared with conventional UAV, the propulsion system of distributed electric propulsion UAV is more complex, which brings difficulties and challenges to the design of distributed electric propulsion UAV. Based on its special aerodynamic/propulsive coupling characteristics, this paper studies the design method and process of primary parameters of distributed electric propulsion UAV. A short takeoff and landing UAV with distributed electric propulsion system is taken as an example for the conceptual design and primary parameter design, and the influence of design parameters on the takeoff mass and endurance is analyzed. Finally, the validity of the established design method is verified by the flight test of the prototype. Results indicate that the distributed electric propulsion system accounts for more than 20% of the takeoff mass; the electric ducted fan efficiency, mass specific power of the motor, mass specific power of the electronic speed controller and the resistivity of power wires are the most significant design parameters that affect the performance of the UAV; with the improvement of technologies, the takeoff mass is expected to be reduced by more than 20%, and the endurance is expected to be increased by more than three times.
A progressive damage model of composite laminates under low-velocity impact
Authors: Zhou Junjie , Wang Shengnan
Published: April 2021

In this paper, a progressive damage model for studying the dynamic mechanical response and damage development of composite laminates under low-velocity impact was established. The model applied the Hashin and Hou failure criteria to predict the initiation of intra-laminar damage (fiber and matrix damage); a linear degradation scheme combined with the equivalent displacement method was adopted to simulate the damage development; a cohesive zone model with the bilinear traction-separation relationship was used to predict delamination. A user material subroutine VUMAT was coded, and the simulation analysis of carbon fiber reinforcement composite laminates subjected to 25 J impact was performed via commercial software ABAQUS. The predicted impact force-time curve, impact force-displacement curve, and damage distribution contours among the layers were in a good agreement with the experimental, which verified the proposed model. According to the simulation results, the fiber damage and matrix damage were analyzed, and the expansion of delamination was discussed.
A detection and restoration approach for vessel trajectory anomalies based on AIS
Authors: Zhang Lixiang , Zhu Yi'an , Lu Wei , Wen Jie , Cui Junyun
Published: April 2021

In view of the continuous increase in the amount of AIS data at sea and the existence of more abnormal points, it is difficult to construct ship trajectories based on AIS data. Aiming at this problem, a new method for identifying and repairing abnormal points in trajectories only based the AIS data of the ship itself is proposed. Longitude and latitude, speed, acceleration, direction and other parameters are comprehensively used to identify and repair the abnormal points in the method proposed. Compared with the methods based on single location data, it can effectively reduce the missed judgement of outliers. Compared with the methods based on trajectories clustering to judge singular point, this method does not require the data of historical trajectories to expand the application scope. The cubic spline method is used to interpolate points for the discontinuous segments to further improve the continuity and integrity of the ship trajectory. The results of AIS data processing and analysis on ships in actual sea areas verify the feasibility and effectiveness of the proposed method.
Redclaw crayfish (Cherax quadricarinatus): spatial distribution and dispersal pattern in Java, Indonesia
Authors: Akmal Surya Gentha , Santoso Agus , Yonvitner  , Yuliana Ernik , Patoka Jiří
Published: April 2021

Cherax quadricarinatus is a parastacid crayfish native to parts of north-eastern Australia and southern New Guinea. It is a relatively large and highly fecund species in comparison with other crayfish of this genus. Since C. quadricarinatus was previously assessed as an invasive species in Indonesia, further monitoring of this species in this region was recommended. Detailed understanding of its spatial behaviour can be the basis for further research aimed at improved management. Field sampling was performed outside its native range in Java, Indonesia from 2019–2020, resulting in data useful for modelling the species' spatial distribution. The occurrence of the species was confirmed in 66 of 70 surveyed localities with 51 new records for Indonesia. Future investigations focused on the relationship between the spatial distribution and dispersal pattern of C. quadricarinatus and its interactions with native biota and entire ecosystems were recommended.