bluuebunny/crossref_metadata_2025 huggingface dataset:
RETRACTED: Driving technology in the path of renewable energy-a review
Authors: Dhanasekar R , Vijayaraja L , Anandan R , Gurusharan G M , Keerthana M , Mahalakshmi E
Published: February 2021

Renewable energy is abundant in nature; it is future of clean energy. The innovation brings down the cost. No damage is caused to the environment by the use of renewable energy, its inexhaustible at any time and is replenished constantly. For example, sunlight and wind is always present. But their availability is depending on the factor’s like time and weather. There are many sources for renewable energy that are accessible in many areas. They cause less pollution compared to conventional energy sources. With current technology, the availability of energy is not at all a problem, but the usage of energy is. The innovation of new technologies gives us hope to a rightful direction of clean energy and clean world without hazard to heavenly beings in the world. These will be the most economical way of future. For a bright future we must drive in the path of renewable energy. The conventional energy sources like natural gas, oil, coal or nuclear are finite and at some point they will get exhausted and more over, the usage of the conventional sources causes pollution and global warming. This paper generally deals about the recent innovations in the field of renewable energy.
A Technical Review on Self-Healing Control Strategy for Smart Grid Power Systems
Authors: Sarathkumar D , Srinivasan M , Stonier Albert Alexander , Samikannu Ravi , Dasari Narasimha Rao , Raj Raymon Antony
Published: February 2021

The various advanced technologies incorporated in the existing power system to operate in smarter and to provide continuity of power supply without any disturbances. Still, it was few threats that disrupting the electrical network to manage the power demand such as: complexity of the power grid; vulnerability to faults; energy efficiency; and renewable energy integration. The above challenges indicate the perception of smart grid (SG). The smart grid design is economic, competent, intelligent and secured grid was needed to manage the above-mentioned issues. Self-healing is the most essential characteristics of a smart grid. The implementation of self-healing control strategy in the smart grid is one of the prolong challenge. It is the capability of the power system network to restore naturally the network when the fault occurs. It gives primary assurance to the smart grid protection. Apart from this, the implementation of various control strategies assist accomplishing the safe functioning, enhancing the stability of the grid. This paper presents the self-healing control strategy in the context of smart grid power systems. The significant advancements developed in the transmission, distribution, micro grid as a result of power electronics converters presented. Then, the information and communication technologies, software tools and measurements which can be employed for winning crucial smart grid self-healing action will be discussed.
IoT Based Smart Energy Metering System for Monitoring the Domestic Load Using PLC and SCADA
Authors: Amudhevalli R , Sivakumar T
Published: February 2021

The effort to obtain electricity utility meter readings and identify illegal use of electricity seems to be a very difficult and time consuming job in many other developing countries that needs a lot of effort and time. The Internet of Things energy meter reading and tracking device offers an accessible and cost effective way to transmit the energy data used by the user wirelessly and information networks to detect the unauthorized use of electricity. This proposed work aims to measure the electricity consumption of the electrical appliances in the house hold and it automatically generates the bill using smart meters. In addition this system can easily detect and screening the energy theft. The entire smart meters sensors have been equipped and controlled with PLC and monitored by the SCADA. The observed data will be taken from the digital energy meter and unite the system to a Wireless communication device and then passes the data to the Internet and Server. The detection of power theft will be obtained by using a sensor, it will work when any illegal usage of electricity. There is any chances of theft detection from the customer utility grid, it will automatically disconnected and enables supply again for the customer. The proposed system can handle of constantly tracking and notifying the energy supplier and the customer about the amount of units consumed. Energy usage is directly calculated and the bill is posted on the Internet through the Internet of Things network. The requirements of manual labor can be reduced by this automation.
Anticipation of Battery Condition Using Internet of Things
Authors: Subramaniya Siva A. , Parthasarathy P. , Gijipriya K. , Vinothini N. , Stonier Albert Alexander
Published: February 2021

Nowadays batteries are becoming so popular because of its feature of storing electric energy enables portability of electric energy even in places where electric transmission lines cannot be laid effortlessly. They are playing a significant role in reaching the objective of universal access to environment friendly, reliable & affordable electricity services. But they are unable to serve their capacity because of their lack of proper monitoring & maintenance. In order to make the battery smarter & safer a system of remote monitoring of battery for determining the battery condition by measuring various parametric quantities of battery & to publicize the condition of battery, thereby maintaining the battery to serve its full capacity as well as to prevent the system from unexpected shutdown.
Acoustic properties of different blending ratios of empty fruit bunch and oil palm frond
Authors: Ewe L S , Nazhan Nasir Mohammad , Yew W K , Mageswaran R , Ibrahim Zawawi
Published: February 2021

The society understands the importance of using sound-absorbing panels to protect our health against the noise pollution. However, the repercussions of fibreglass as sound-absorbing panels on human health and the environment have increased year by year. Natural fibers are more environmentally friendly and have significantly lower production cost. This research emphasizes the acoustic properties of different blending ratios of Empty Fruit Bunch (EFB) and Oil Palm Frond (OPF at four different thickness. Their acoustic properties were tested by using the Impedance Tube Method (ITM) from frequency range of 0 - 6400 Hz. The findings show the Sound Absorption Coefficient (SAC) value increases as the frequency increases for all samples. Both blending ratios have good SAC results. For blending ratio of 30% EFB – 70% OPF, the SAC of the panels achieved 80% and above at frequency between 3500 - 6400 Hz for samples with thickness of 14 mm, 16 mm and 18 mm. However, for blending ratio of 20% EFB – 80% OPF, the SAC of all samples are found 0.8 and above at frequency between 3500 - 6400 Hz. Notably, the SAC values for both blending ratio are increased with increasing in thickness. It might be attributed to the effect of tortuosity. The SAC values for all samples are also found to achieve unity ( ∼ 0.96 ) at different frequency range. Furthermore, the frequency range for SAC to reach 0.8 and above has been increased from 4500 – 6400 Hz to 3500 – 6400 Hz with an increased in OPF contents.
The effect of graphene addition on the Young’s modulus and tensile strength of kenaf fibre composites
Authors: Afiqah Mohd Radzuan Nabilah , Gunasegran Mihirssen , Naima Khalid Nisa
Published: February 2021

Natural fibres such as kenaf fibres may be used to reinforce polymer matrices such as polypropylene (PP). Such composite materials are in demand for the production of interior components for automotive vehicles due to their low density (1.2 g/cm³) and good mechanical properties (Young’s modulus of 11 GPa and tensile strength of 780 MPa). The main objective of this study is to determine the effect of the addition of graphene fillers to the tensile strength and Young’s modulus of kenaf fibre composites. For this kenaf/graphene/polypropylene (PP) composites are to be studied via computer simulations using Abaqus CAE software and to compare the experimental data of Young’s modulus and tensile strength of the composite from previous researchers with the results of the simulations. For the Abaqus CAE simulations, general static and dynamic explicit analyses were conducted and set at 20 wt. % kenaf fibres, 0, 1, 3, to 5 wt. % graphene. The highest value of Young’s modulus was 1 600 MPa achieved with the material with composition of PP/kenaf/graphene 5 wt. % while the highest value of tensile strength was achieved by the composition of PP/kenaf/graphene 1 wt. % at 23.07 MPa. On the other hand, the values of tensile strength increase with the addition of graphene (1 wt. %) at first due to the improvement of interface adhesion between the polymer matrix and non-organic particles. Further addition of graphene content (3 – 5 wt. %) results in a decrease of tensile strength due to the presence of agglomeration and defects such as voids and fibre pull-outs which weakens the adhesion between the fibres and matrix. The addition of graphene to PP/kenaf composites was proved to improve the Young’s modulus and tensile strength of the materials. This improves the suitability of the materials in the production of interior components for automotive vehicles.
Additive manufacturing in medical applications: A brief review
Authors: Sun Bo , Ma Quanjin , Wang Xinfu , Liu Jinyan , Rejab M R M
Published: February 2021

In the medical field, due to the obvious individual differences between patients, the complexity of human tissues and the fact that patients are too price-sensitive, it is desperate to search for a new biological material adjuvant therapy, which far more closely matches the pathological characteristics of patients. It is noted that additive manufacturing has the ability to overcome those limitations by virtue of its exclusive characteristics of personalized customization, small-scale production and high precision. This paper aims to summarize the characteristics and applications of 3D printing technology used at four levels in the medical field, including adjuvant therapy and anatomical model, implants and scaffolds, biological 3D printing, and pharmaceuticals, as well as, to present the recent innovation and discuss existing issues with 3D printing that related to medical applications. It is highlighted that 3D printing technology will be further built on medical application.
Investigation on linear and nonlinear dynamic equation for vehicle model in numerical simulation
Authors: Maoqi Li , Ishak M I , Heerwan P M
Published: February 2021

With the increase in vehicles in the world today, more accidents have occurred. Therefore, more safety systems are needed for conventional vehicles. However, physical testing is dangerous and costly compared with numerical simulation. So, a good numerical simulation is especially important. In general, the vehicle dynamics equations were used in the numerical simulation. There are two types of vehicle dynamics equations that are linear and nonlinear. This paper researched which one is more practical between linear and nonlinear equations in the simulations versus real-time experiments. In this paper, the equation of motion was used to simulate the state of vehicle motion during cornering conditions in the MatLab Simulink software. The results show that the value of the linear and non-linear yaw is close to the yaw from experimental at lower speed conditions. With the speed increase, the linear yaw value will decrease and farther and farther away from experimental yaw results. Although the linear equation is relatively simple to calculate, the results of the nonlinear equations are closer to the results of real experiments. In summary, the nonlinear equation is more applicable, while the linear equation is not applicable to simulate the motion of the vehicle.
Design and simulation of solar roof-top projects for an energy self-reliant university campus
Authors: Ajithgopi  , Sudhakar K , Wai Keng Ngui
Published: February 2021

A University campus becoming self-reliant in terms of electricity generation is always important. The power requirement of a University campus is mainly for its academic blocks for different departments. The laboratories, libraries, and hostel facilities also require continuous power needs. Conventionally, the electricity needs are met utilizing the power received from the local utility and the University will be paying for it based on the tariff fixed by the local regulators and agreed by the utility. It is proposed to install Solar Roof-top PV power plants in shade-free rooftops of the buildings inside a University campus to offset the University’s electricity needs and to make the University self-reliant in terms of electricity generation and consumption. This integrated and comprehensive solar project is intended to reduce the carbon footprint of the University and aiming for a carbon-neutral campus. Detailed feasibility studies have been conducted for installing solar roof-top power plants in the selected building roof-tops of the University. Based on the feasibility study, design and simulation have been carried out for a total 1.6MWp capacity of solar roof-top projects to completely offset the total electricity needs of the University based on the current electricity consumption patterns. The design and simulation are accomplished utilizing PVsyst software and the economic and environmental analysis has been carried out utilizing RETscreen software for arriving at the results.
Cotton waste research follows the effect of pre-treatment and the observation of physical appearance
Authors: Mahamude A S F , Harun W S W , Kadirgama K , Ramasamy D , Farhana K
Published: February 2021

This paper aims to evaluate the waste cotton quality and its commercialization. The recycled cotton demand seems to be increased day by day: although the lower quality of the resulting items is the biggest barrier to cotton recycling. A thorough analysis of recycled cotton processes is therefore necessary from separation/shredding to completion. To that end, textile wastes made of pre-consumer cotton were systematically collected from the spinning mill. After pretreatment of cotton waste cellulose by caustic soda, alkali, and detergent in 100°C temperature for 30 minutes have produced white clean cotton. Following the next process by sodium hydroxide and isopropyl alcohol must produce Carboxymethyl Cellulose (CMC). CMC has big use in Textile printing, finishing, and warp sizing even in Ice-cream and food baking industry. Recent success stories will be addressed with the steady cotton processing to altering the properties of cell wall cotton and cotton fiber. The prospects of conducting experiments of waste cotton and checking the properties of treated cotton have a great value in the production of commercial products and the results relived that the value addition of waste cotton is a very easy method.
Formation of colours on SS304L stainless steel induced by laser colouring
Authors: Linggamm R , Quazi M M , Ishak M , Aiman M H , Zafiuddin A Q , Qaban Abdullah
Published: February 2021

In this research, the laser colour marking process was carried out to determine the formation of colour on surface of SS304L stainless steel. The pulse laser nanosecond (1064nm) was used to irradiate the SS304, resulting in the formation of various colour permeating on the sample surface. The surface characterization and surface roughness were analysed by using the 3D optical microscope. The effect of laser processing parameters such as hatching distance, pulse width, and defocusing distance on the evolution of surface colours were investigated. The results show that a thin oxide film was essentially formed that resulted in the formation of four different colours. Each colour exhibited a different surface texture and surface roughness implying the effect of parameters significantly affects the surface characteristics. Grey colour formed registered the highest roughness (Rz) of about 3.5 microns followed by a decreasing roughness trend for blue, purple and green respectively.
Enhancement of tribological behaviour and thermophysical properties of engine oil lubricant by Graphene/Co-Cr nanoparticle additives for preparation of stable nanolubricant
Authors: Sandhya M , Ramasamy D , Kadirgama K , Harun W S W , Samykano M , Ameer A
Published: February 2021

In the current study the tribological properties of Aluminum alloy (Al 25) with moment in time was examined by adding nanoparticles as additives. Nanoparticles exhibit high thermal conductivity, stable viscosity and can be dispersed well in oil. The purpose of this research is to determine the effect of Al2O3, TiO2, Graphene (G), Co-Cr, Ni nanoparticles on lubricity using linear wear testers under reciprocating sliding motion. SEM and EDX characterization techniques are used to study the composition and morphology on worn surfaces. The findings showed that the tribological properties of the substrate lubricant were significantly increased with the addition of nanoparticles. Friction and Wear are reduced with Graphene, Al2O3, TiO2, Ni & Co-Cr nanoparticles as additives for the same load value and can be used as multifunctional additives. Co-Cr at 0.03wt% has provided best performance among the other nanoparticles and can be used as Nano lubricant in the future.
Preparation of metal-organic frameworks (MOFs) based Chromium 2,6-Naphtalenedicarboxylic Acid (MIL-101 NDC) for CO2 adsorption application
Authors: Yulia Fayza , Utami V J , Nanda Raden , Nasruddin  , Arif Budiyanto Muhammad , Zulys A
Published: February 2021

Metal-organic frameworks are believed to be one of the solutions in reducing CO2 emissions. Ligand modification, which is one of the methods in optimizing the MOF structure, provides a good opportunity for the development of functional materials with better properties. Ligand functionality in gas separation is important because it provides an insight of the influence of the material topology. MIL-101 (Cr), which is a type of MOF, is composed of metal chromium and terephthalic acid as the linker. This MOF has been extensively researched for CO2 capture applications. In this work, the functionalization of MIL-101 with 1,4-Benzenedicarboxylic acid (BDC) as the ligand was carried out by changing into 2,6-Napthalenedicarboxylic acid (NDC) ligand. The design and architecture of NDC, which has a double hydrocarbon ring, is expected to increase the pore and surface area of the MOF so that it can increase gas adsorption. The synthesis of the modified MOF was performed using solvothermal method and tested for the porous properties, morphology, structure, chemical functionalities and thermal stability by N2 adsorption / desorption data, scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). The results show that MIL-101 NDC has better thermal stability, as it can maintain its structure up to the temperature of 350°C. The pore diameter measurement results also show a good diameter up to 4nm. The discovery structure of MIL-101 NDC which has excellent stability provides a good prospective adsorbent in CO2 capture applications.
Microstructure analysis and mechanical properties of dissimilar AA6061-AA7075 laser brazing with prefixed ER5356 filler
Authors: Haneef M S , Aiman M H , Salleh M N M , Quazi M M , Ishak M
Published: February 2021

Laser brazing uses a filler metal for joining without melting the base material. This process is a versatile joining technique for a wide range of applications including automotive, aerospace, and medical field because of the ability in joining dissimilar metal and resulted good quality in surface’s joint. This study consists of aluminium alloy of AA6061 and AA7075 as a base material with aluminium based ER5356 as a wire filler. Laser brazing was performed using 1.2 kW of laser power, while wire filler was let to be prefixed without using the wire feeder because of using the existing laser welding machine. Microstructure of the joints were studied using 3D measuring laser microscope OLS5000. Besides that, mechanical properties of the joints were evaluated by performing tensile test and hardness test. Microstructures of the brazed joints show the differences in the grain structure followed by the difference’s hardness value on each region. The brazed joint shows the average ultimate tensile strength reached 154.71 MPa which was 50% of joint efficiency. However, there is porosities at the fracture surface of the joint.
Leak diagnosis of pipeline based on empirical mode decomposition and support vector machine
Authors: Faysal A , Adhreena M S N A , Vorathin E , Hafizi Z M , Ngui W K
Published: February 2021

The pipeline is used as a medium of transportation in global gas and oil industries, providing the most efficient, convenient and transportation method for natural gas and oil from downstream to upstream production of the economical mode of the power station, refineries, and domestic needs. However, the pipeline leakages become a major concern as their failure may contribute to operational and economic loss as well as environmental pollution. This paper proposed a system to detect pipe fault at different locations. Empirical Mode Decomposition (EMD) was applied for feature extraction using energy and kurtosis. The one-against-one (OAO) and one-against-all (OAA) multiclass SVM with radial basis function (RBF), polynomial and sigmoid kernel functions were implemented in order to classify the multiple fault locations from the extracted features. RBF kernel function recorded the highest classification accuracy for both OAO and OAA approaches with 97.77% and 96.29%, respectively, followed by slightly reduced accuracy for sigmoid whereas significantly low accuracy for the polynomial kernel. The outputs were further analysed to justify the performance of the classifiers. From all the cases, it was observed that OAO-SVM with RBF kernel performed the best for pipe fault diagnosis.
Investigation of pipe materials and thermal conductivity of soil on the performance of ground heat exchanger operating under Malaysia climate
Authors: Aizzuddin A M , Yusof T M , Azmi W H
Published: February 2021

In nature, renewable energy is inherently free and must be implemented. The use of air conditioning and refrigerants that affect global warming is a serious issue. In building applications, renewable energy from the geothermal source, namely ground heat exchanger (GHE), has great potential. The main concept of GHE is utilizing the ground as an infinite thermal reservoir for cooling and heating to the fluid medium. In the GHE system, the air is used as a fluid medium of work. Because of the temperature difference between the air and underground temperature, the air cools in summer and gets heated in winter. In this present work, a study has been conducted to investigate the effect of pipe materials and thermal conductivity of soil on the performance of the GHE. The study acknowledges that the pipe materials do not give a significant effect on the performance of the GHE. Therefore, the lower thermal conductivity of pipe materials with low cost can be used in GHE implementation. The study also revealed that the range of thermal conductivity of soil which gives good ground heat exchanger performance is between 1.5 to 5 W/m·K. Besides, the length of the pipe was reduced from 25 to 10 meters.
Nanoparticles synthesised from Caesalpinia spinosa: assessment of the antifungal effects in protective systems
Authors: Gámez-Espinosa Erasmo , Deyá Cecilia , Cabello Marta , Bellotti Natalia
Published: February 2021

Green chemistry is the preferred approach for the synthesis of metal and metal oxide nanoparticles due to its environmental friendliness, feasibility, and safety to human health when compared with other chemical or physical methods. Caesalpinia spinosa is a promising resource to be applied in the green synthesis of metallic nanoparticles due to the high amount of polyphenols. The aim of the present research was to obtain an antifungal coating functionalised with nanoparticles synthesised from C. spinosa tannin and aqueous solutions of metallic (silver and copper) salts to control biodeterioration of acrylic paints and bricks. Green synthesised NPs were characterised by UV-vis spectroscopy, transmission electron microscopy (TEM), Fourier transformed infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and energy dispersive x-ray spectroscopy (EDS). The silver nanoparticles with average size of 12 nm and obtained from a 500 ppm aqueous solution of C. spinosa tannin inhibited the growth of Aspergillus niger, Penicillium commune and Lasiodiplodia theobromae. These strains were previously isolated from a biodeteriorated facade. Functionalised coating obtained with silver nanoparticles synthesised from C. spinosa tannin is reported for the first time as antifungal protective system of acrylic paints and bricks.
High harmonic generation driven by two-color relativistic circularly polarized laser pulses at various frequency ratios
Authors: XIE Duan , YIN Yan , YU Tongpu , ZHOU Hongyu , CHEN Ziyu , ZHUO Hongbin
Published: February 2021

High harmonic generation (HHG) by two-color counter-rotating relativistic laser pulses with arbitrary frequency ratio is investigated through particle-in-cell simulations. It is shown that the dichromatic laser driver at various frequency ratios can effectively produce high-order harmonics with different spectral features. A general selection rule of this extended scheme can be obtained and the corresponding harmonic helicity can be identified through a simple analytical model based on a relativistic oscillating mirror. Thus, the results in this paper may offer new opportunities for arbitrary spectral control of generated harmonics, which is of significance for diverse potential applications in practice.
Hybrid coffee cultivars may enhance agroecosystem resilience to climate change
Authors: Pappo Emily , Wilson Chris , Flory S Luke
Published: February 2021

Anthropogenic climate change is predicted to cause shifts in temperature and precipitation patterns that will be detrimental for global agriculture. Developing comprehensive strategies for building climate resilient agroecosystems is critical for maintaining future crop production. Arabica coffee (Coffea arabica) is highly sensitive to the quantity and timing of precipitation, so alterations in precipitation patterns that are predicted under climate change are likely to be a major challenge for maintaining coffee agroecosystems. We assessed cultivar selection as a potential component of more resilient coffee agroecosystems by evaluating water stress responses among five Arabica coffee cultivars (clonal hybrids H10 and H1 and seedling lines Catuai 44, Catuai, and Villa Sarchi) using a precipitation reduction experiment in the highlands of Tarrazú, Costa Rica. During the first harvest (eighteen months after planting), plants under the rainout treatment had 211 % greater total fruit weight and over 50 % greater biomass than under the control treatment, potentially due to protection from unusually high rainfall during this period of our experiment. At the second harvest (30 months after planting), after a year of more typical rainfall, plants under rainout still produced 66 % more fruit by weight than under control. The magnitude of the responses varied among cultivars where, at the first harvest, H10 and H1 had approximately 92 % and 81 % greater fruit production and 18 % and 22 % greater biomass, respectively, and at the second harvest H10 had 60 % more fruit production than the overall average. Thus, our findings suggest that the hybrid lines H10 and H1 are more resilient than the other cultivars to the stress of high soil moisture. Overall, our results indicate that stress due to higher than average rainfall could impair coffee plant growth and production, and that cultivar selection is likely to be an important tool for maintaining the viability of coffee production, and the resilience of global agroecosystems more generally, under climate change.
A novel route for aspartame production by combining enzymatic and chemical reactions for industrial use
Authors: Yokozeki Kenzo , Abe Isao
Published: February 2021

Here, we report a novel industrial aspartame production route, involving the enzymatic production of α-l-aspartyl-l-phenylalanine β-methylester from l-aspartic acid dimethylester and l-phenylalanine by α-amino acid ester acyl transferase. The route also involves the chemical transformation of α-l-aspartyl-l-phenylalanine β-methylester to α-l-aspartyl-l-phenylalanine methylester hydrochloride (aspartame hydrochloride) in an aqueous solution with methanol and HCl, followed by HCl removal to form aspartame.
ESCO: single cell expression simulation incorporating gene co-expression
Authors: Tian Jinjin , Wang Jiebiao , Roeder Kathryn
Published: February 2021

Motivation

Gene-gene co-expression networks (GCN) are of biological interest for the useful information they provide for understanding gene-gene interactions. The advent of single cell RNA-sequencing allows us to examine more subtle gene co-expression occurring within a cell type. Many imputation and denoising methods have been developed to deal with the technical challenges observed in single cell data; meanwhile, several simulators have been developed for benchmarking and assessing these methods. Most of these simulators, however, either do not incorporate gene co-expression or generate co-expression in an inconvenient manner.

Results

Therefore, with the focus on gene co-expression, we propose a new simulator, ESCO, which adopts the idea of the copula to impose gene co-expression, while preserving the highlights of available simulators, which perform well for simulation of gene expression marginally. Using ESCO, we assess the performance of imputation methods on GCN recovery and find that imputation generally helps GCN recovery when the data are not too sparse, and the ensemble imputation method works best among leading methods. In contrast, imputation fails to help in the presence of an excessive fraction of zero counts, where simple data aggregating methods are a better choice. These findings are further verified with mouse and human brain cell data.

Availability and implementation

The ESCO implementation is available as R package ESCO. Users can either download the development version via github (https://github.com/JINJINT/ESCO) or the archived version via Zenodo (https://zenodo.org/record/4455890).

Supplementary information

Supplementary data are available at Bioinformatics online.
HIR V2: a human interactome resource for the biological interpretation of differentially expressed genes via gene set linkage analysis
Authors: Guo Wen-Ping , Ding Xiao-Bao , Jin Jie , Zhang Hai-bo , Yang Qiao-lei , Chen Peng-Cheng , Yao Heng , Ruan L i , Tao Yu-Tian , Chen Xin
Published: February 2021

To facilitate biomedical studies of disease mechanisms, a high-quality interactome that connects functionally related genes is needed to help investigators formulate pathway hypotheses and to interpret the biological logic of a phenotype at the biological process level. Interactions in the updated version of the human interactome resource (HIR V2) were inferred from 36 mathematical characterizations of six types of data that suggest functional associations between genes. This update of the HIR consists of 88 069 pairs of genes (23.2% functional interactions of HIR V2 are in common with the previous version of HIR), representing functional associations that are of strengths similar to those between well-studied protein interactions. Among these functional interactions, 57% may represent protein interactions, which are expected to cover 32% of the true human protein interactome. The gene set linkage analysis (GSLA) tool is developed based on the high-quality HIR V2 to identify the potential functional impacts of the observed transcriptomic changes, helping to elucidate their biological significance and complementing the currently widely used enrichment-based gene set interpretation tools. A case study shows that the annotations reported by the HIR V2/GSLA system are more comprehensive and concise compared to those obtained by the widely used gene set annotation tools such as PANTHER and DAVID. The HIR V2 and GSLA are available at http://human.biomedtzc.cn.
Haemodynamic benefit of bridging use of bosentan prior to pulmonary endarterectomy
Authors: Kunihara Takashi , Wilkens Heinrike , Halank Michael , Held Matthias , Nomura Ryota , Igarashi Takashi , Sata Fumihiro , Schäfers Hans-Joachim
Published: February 2021

OBJECTIVES

Some patients present with excessive pulmonary hypertension (PH) prior to pulmonary endarterectomy (PEA) for chronic thromboembolic pulmonary hypertension (CTEPH). This study was performed to evaluate the clinical role of pretreatment before PEA in CTEPH patients.

METHODS

A total of 370 patients with CTEPH undergoing first PEA between 2003 and 2017 were divided into those receiving pretreatment with bosentan (group B: n = 119) and those without targeted pretreatment for PH (group C: n = 251). After selecting patients given bosentan (2–8 months) and using propensity score matching, comparable patient cohorts (n = 23 each) were created from both groups. PEA was performed in the standard manner, and the median number of extracted segments was 14.

RESULTS

There were no significant differences in perioperative demographic characteristics or 30-day mortality (overall 5.7%) between the groups before and after matching. In patients with preoperative pulmonary vascular resistance (PVR) ≥800 dynes s/cm5, a significantly larger decrease in PVR was found in group B (78%) compared to group C (68%) (P = 0.033). There was no significant difference in late survival between the groups after matching. The frequency of residual/persistent PH (mean pulmonary artery pressure >25 mmHg) was lower in group B than in group C, although the difference was not significant (22% vs 39%, respectively, P = 0.200). Advanced age and longer cardiopulmonary bypass time were independent predictors of both 30-day mortality and residual/persistent PH (odds ratio: age, 1.053, 1.013, cardiopulmonary bypass time, 1.065, 1.010, respectively).

CONCLUSIONS

Preoperative treatment of CTEPH patients with bosentan for 2–8 months can improve post-PEA PVR without adverse clinical events in patients with a high preoperative PVR. A temporary bridging regime appears beneficial in selected patients prior to PEA.
Twitter for professional use in electrophysiology: practical guide for #EPeeps
Authors: Linz Dominik , Garcia Rodrigue , Guerra Federico , Kommata Varvara , Bollmann Andreas , Duncker David
Published: February 2021

Social media (SoMe) becomes more and more popular in the cardiological community. Among them, Twitter is an emerging and dynamic medium to connect, communicate and educate academic and clinical cardiologists. However, in contrast to traditional scientific communications, the content provided through SoMe is not peer-reviewed and may not necessarily always represent scientific evidence or may even be used to unjustifiably promote therapies for commercial purposes. For the unintended, this means of communication might be appear difficult to handle. This article aims to provide a practical guide on how to use Twitter efficiently for professional use to keep yourself up-to-date about new techniques, the latest study results and news presented at national or international conferences. Additionally, important limitations will be discussed.
Similar solutions to a common challenge: regulation of genes encoding Ralstonia solanacearum xanthine dehydrogenase
Authors: Sivapragasam Smitha , Ghosh Arpita , Kumar Sanjay , Johnson Danté T , Grove Anne
Published: February 2021

The stringent response involves accumulation of (p)ppGpp, and it ensures that survival is prioritized. Production of (p)ppGpp requires purine synthesis, and upregulation of an operon that encodes the purine salvage enzyme xanthine dehydrogenase (Xdh) has been observed during stringent response in some bacterial species, where direct binding of ppGpp to a TetR-family transcription factor is responsible for increased xdh gene expression. We show here that the plant pathogen Ralstonia solanacearum has a regulatory system in which the LysR-family transcription factor XanR controls expression of the xan operon; this operon encodes Xdh as well as other enzymes involved in purine salvage, which favor accumulation of xanthine. XanR bound upstream of the xan operon, a binding that was attenuated on addition of either ppGpp or cyclic di-guanosine monophosphate (c-di-GMP). Using a reporter in which enhanced green fluorescent protein (EGFP) is expressed under control of a modified xan promoter, XanR was shown to repress EGFP production. Our data suggest that R. solanacearum features a regulatory mechanism in which expression of genes encoding purine salvage enzymes is controlled by a transcription factor that belongs to a different protein family, yet performs similar regulatory functions.
Microbial analyses of blood spot surfaces collected from a laboratory and the bathroom of a female single-person household under different environmental conditions
Authors: You Hee Sang , Lee Song Hee , Lee Young Ju , Sung Ho Joong , Kang Hee-Gyoo , Hyun Sung Hee
Published: February 2021

Many people spend most of their time indoors, thereby exposing themselves to indoor environmental microbial communities that might interact with the human microbiota. These potential interactions have only been considered for personal identification; however, accumulating evidence indicates that these microbial interactions are potentially implicated with the identification of human interactions and location-specific factors including time and seasonal variations in the microbial community. To augment the potential of metagenomics-based forensic tools, we compared the composition of microbial communities in blood spot surfaces from healthy adults placed in different environments, such as in the bathroom of a female single-person household and on a laboratory, which were sampled across seasons and time points. The laboratory samples showed more changes in the bacterial community over time owing to the higher number of individuals using the laboratory, whereas the microbial communities in the bathroom samples remained relatively stable over time. Moreover, the two locations could be distinguished according to their specific bacterial community compositions. Variations were also observed related to changes in temperature and humidity, allowing for prediction of season-based microbial community. These findings offer a new perspective regarding the use of microbial community analysis in forensic science.
Common genetic polymorphisms contribute to the association between chronic lymphocytic leukaemia and non-melanoma skin cancer
Authors: Besson Caroline , Moore Amy , Wu Wenting , Vajdic Claire M , de Sanjose Silvia , Camp Nicola J , Smedby Karin E , Shanafelt Tait D , Morton Lindsay M , Brewer Jerry D , Zablotska Lydia , Engels Eric A , Cerhan James R , Slager Susan L , Han Jiali , Berndt Sonja I ,   the InterLymph Consortium. Full authors list is given at the end of the manuscript
Published: February 2021

Background

Epidemiological studies have demonstrated a positive association between chronic lymphocytic leukaemia (CLL) and non-melanoma skin cancer (NMSC). We hypothesized that shared genetic risk factors between CLL and NMSC could contribute to the association observed between these diseases.

Methods

We examined the association between (i) established NMSC susceptibility loci and CLL risk in a meta-analysis including 3100 CLL cases and 7667 controls and (ii) established CLL loci and NMSC risk in a study of 4242 basal cell carcinoma (BCC) cases, 825 squamous cell carcinoma (SCC) cases and 12802 controls. Polygenic risk scores (PRS) for CLL, BCC and SCC were constructed using established loci. Logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Higher CLL-PRS was associated with increased BCC risk (OR4th-quartile-vs-1st-quartile = 1.13, 95% CI: 1.02–1.24, Ptrend = 0.009), even after removing the shared 6p25.3 locus. No association was observed with BCC-PRS and CLL risk (Ptrend = 0.68). These findings support a contributory role for CLL in BCC risk, but not for BCC in CLL risk. Increased CLL risk was observed with higher SCC-PRS (OR4th-quartile-vs-1st-quartile = 1.22, 95% CI: 1.08–1.38, Ptrend = 1.36 × 10–5), which was driven by shared genetic susceptibility at the 6p25.3 locus.

Conclusion

These findings highlight the role of pleiotropy regarding the pathogenesis of CLL and NMSC and shows that a single pleiotropic locus, 6p25.3, drives the observed association between genetic susceptibility to SCC and increased CLL risk. The study also provides evidence that genetic susceptibility for CLL increases BCC risk.
Host apoplastic cysteine protease activity is suppressed during the mutualistic association ofLolium perenneandEpichloë festucae
Authors: Passarge Andrea , Demir Fatih , Green Kimberly , Depotter Jasper R L , Scott Barry , Huesgen Pitter F , Doehlemann Gunther , Misas Villamil Johana C
Published: February 2021

Plants secrete various defence-related proteins into the apoplast, including proteases. Papain-like cysteine proteases (PLCPs) are central components of the plant immune system. To overcome plant immunity and successfully colonize their hosts, several plant pathogens secrete effector proteins inhibiting plant PLCPs. We hypothesized that not only pathogens, but also mutualistic microorganisms interfere with PLCP-meditated plant defences to maintain endophytic colonization with their hosts. Epichloë festucae forms mutualistic associations with cool season grasses and produces a range of secondary metabolites that protect the host against herbivores. In this study, we performed a genome-wide identification of Lolium perenne PLCPs, analysed their evolutionary relationship, and classified them into nine PLCP subfamilies. Using activity-based protein profiling, we identified four active PLCPs in the apoplast of L. perenne leaves that are inhibited during endophyte interactions. We characterized the L. perenne cystatin LpCys1 for its inhibitory capacity against ryegrass PLCPs. LpCys1 abundance is not altered during the mutualistic interaction and it mainly inhibits LpCP2. However, since the activity of other L. perenne PLCPs is not sensitive to LpCys1, we propose that additional inhibitors, likely of fungal origin, are involved in the suppression of apoplastic PLCPs during E. festucae infection.
Structure-guided protein engineering of human cathepsin L for efficient collagenolytic activity
Authors: Choudhury Debi , Biswas Sampa
Published: February 2021

Engineering precise substrate specificity of proteases advances the potential to use them in biotechnological and therapeutic applications. Collagen degradation, a physiological process mediated by collagenases, is an integral part of extracellular matrix remodeling and when uncontrolled, implicated in different pathological conditions. Lysosomal cathepsin-K cleaves triple helical collagen fiber, whereas cathepsin-L cannot do so. In this study, we have imparted collagenolytic property to cathepsin-L, by systematically engineering proline-specificity and glycosaminoglycans (GAG)-binding surface in the protease. The proline-specific mutant shows high specificity for prolyl-peptidic substrate but is incapable of cleaving collagen. Engineering a GAG-binding surface on the proline-specific mutant enabled it to degrade type-I collagen in the presence of chondroitin-4-sulfate (C4-S). We also present the crystal structures of proline-specific (1.4 Å) and collagen-specific (1.8 Å) mutants. Finally docking studies with prolyl-peptidic substrate (Ala-Gly-Pro-Arg-Ala) at the active site and a C4-S molecule at the GAG-binding site enable us to identify key structural features responsible for collagenolytic activity of cysteine cathepsins.
Current status of space gravitational wave antenna DECIGO and B-DECIGO
Authors: Kawamura Seiji , Ando Masaki , Seto Naoki , Sato Shuichi , Musha Mitsuru , Kawano Isao , Yokoyama Jun’ichi , Tanaka Takahiro , Ioka Kunihito , Akutsu Tomotada , Takashima Takeshi , Agatsuma Kazuhiro , Araya Akito , Aritomi Naoki , Asada Hideki , Chiba Takeshi , Eguchi Satoshi , Enoki Motohiro , Fujimoto Masa-Katsu , Fujita Ryuichi , Futamase Toshifumi , Harada Tomohiro , Hayama Kazuhiro , Himemoto Yoshiaki , Hiramatsu Takashi , Hong Feng-Lei , Hosokawa Mizuhiko , Ichiki Kiyotomo , Ikari Satoshi , Ishihara Hideki , Ishikawa Tomohiro , Itoh Yousuke , Ito Takahiro , Iwaguchi Shoki , Izumi Kiwamu , Kanda Nobuyuki , Kanemura Shinya , Kawazoe Fumiko , Kobayashi Shiho , Kohri Kazunori , Kojima Yasufumi , Kokeyama Keiko , Kotake Kei , Kuroyanagi Sachiko , Maeda Kei-ichi , Matsushita Shuhei , Michimura Yuta , Morimoto Taigen , Mukohyama Shinji , Nagano Koji , Nagano Shigeo , Naito Takeo , Nakamura Kouji , Nakamura Takashi , Nakano Hiroyuki , Nakao Kenichi , Nakasuka Shinichi , Nakayama Yoshinori , Nakazawa Kazuhiro , Nishizawa Atsushi , Ohkawa Masashi , Oohara Kenichi , Sago Norichika , Saijo Motoyuki , Sakagami Masaaki , Sakai Shin-ichiro , Sato Takashi , Shibata Masaru , Shinkai Hisaaki , Shoda Ayaka , Somiya Kentaro , Sotani Hajime , Takahashi Ryutaro , Takahashi Hirotaka , Akiteru Takamori , Taniguchi Keisuke , Taruya Atsushi , Tsubono Kimio , Tsujikawa Shinji , Ueda Akitoshi , Ueda Ken-ichi , Watanabe Izumi , Yagi Kent , Yamada Rika , Yokoyama Shuichiro , Yoo Chul-Moon , Zhu Zong-Hong
Published: February 2021

The Deci-hertz Interferometer Gravitational Wave Observatory (DECIGO) is a future Japanese space mission with a frequency band of 0.1 Hz to 10 Hz. DECIGO aims at the detection of primordial gravitational waves, which could have been produced during the inflationary period right after the birth of the Universe. There are many other scientific objectives of DECIGO, including the direct measurement of the acceleration of the expansion of the Universe, and reliable and accurate predictions of the timing and locations of neutron star/black hole binary coalescences. DECIGO consists of four clusters of observatories placed in heliocentric orbit. Each cluster consists of three spacecraft, which form three Fabry–Pérot Michelson interferometers with an arm length of 1000 km. Three DECIGO clusters will be placed far from each other, and the fourth will be placed in the same position as one of the other three to obtain correlation signals for the detection of primordial gravitational waves. We plan to launch B-DECIGO, which is a scientific pathfinder for DECIGO, before DECIGO in the 2030s to demonstrate the technologies required for DECIGO, as well as to obtain fruitful scientific results to further expand multi-messenger astronomy.