bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and Analysis of Intelligent Home System for Remote Control of Luminance by Mobile Terminal
Authors: Zhai Dong , Li HongWei
Published: July 2020

Nowadays, the Internet provides a strong technical support for the construction and development of smart home.Smart home sets the user’s living environment as the central platform, and USES many technologies such as Internet of things, radio frequency identification, etc., to practice the unification, intelligent management and regulation of all indoor household appliances, which has obviously improved people’s living quality and created convenient conditions for users to manage household appliances.Under the pressure of high technology, the current smart home products on the market are of various types, diverse functions, each has its own advantages, most of the products are mainly used to regulate the switch quantity, analog quantity control involved in the degree of insufficient, unable to achieve the indoor lighting degree of fast and accurate regulation.This paper mainly develops a remote control system based on Android mobile terminal, and explores the specific method for the system to control the brightness of smart home lamps, so as to further improve the level of intelligence of smart home and the satisfaction of residents.
The Application of Artificial Intelligence in Agriculture
Authors: Zhao Baogui
Published: July 2020

In today’s society, data resources have become strategic resources as important as material resources, energy resources and human resources, which is the embodiment of a country’s digital subject and comprehensive national strength. The purpose of this paper is to study the application of artificial intelligence in the field of agriculture. It is of great practical significance and practical value for promoting the transformation and upgrading of traditional agriculture and promoting the development of intelligent agriculture. Based on the characteristics of the agricultural field, this paper defines intelligent agriculture, analyzes the process of intelligent agriculture, designs the general framework of agricultural technology, and thinks about the technical route of the development of intelligent agriculture. Then, based on the process theory, the application of acquisition technology, management technology and processing technology in the agricultural field is studied and discussed with specific examples. The results show that the processing rate of large production data is improved by 92.1%. Based on the experimental results, this paper puts forward some opinions on the development of intelligent agriculture, which can provide reference and basis for further promoting the application of artificial intelligence technology in agriculture.
Optimal Operation Strategy of Multi-energy System
Authors: Tang Yanmei , Li Kecheng , Wang Shanyou , Jin Lu
Published: July 2020

Multiple energy system could meet the needs of the user through different energy conversion ways. So if the load level is constant, the operating state of energy system could be different to meet different demand. By the analysis of energy flow of system, it can be known that the degrees of freedom come from the dispatch point of energy flow. Therefore, the dispatch factors and the input energy flows could be considered as the independent variables, and make a comprehensive evaluation criterion which considered the energy efficiency, economy and emission, as the optimization goal. The operation of the multi-energy flow system has been optimized. Through case analysis, the proposed optimal energy flow operation strategy was verified and analysed.
Low Carbon Multi-Objective Shop Scheduling Based On Genetic and Variable Neighborhood Algorithm
Authors: Yang Xingbo , Zhang Junhao , Zhang Ningbo , Li Yawei
Published: July 2020

Aiming at the low-carbon scheduling problem of flexible job shop, the carbon emission and key scheduling objectives of machining system are studied. Firstly, the carbon emissions directly generated by machines and indirectly generated by waste treatment are considered in the calculation of carbon emissions, and then a multi-objective optimization model is established with completion time, total machine load and carbon emissions as the objective function; secondly, the hybrid algorithm of genetic variable neighborhood is designed to solve the optimization model, and the completion time, total machine load. Finally, the production example is simulated in Matlab environment. The experimental results show that the multi-objective scheduling model is feasible and effective. According to the production situation of the workshop, the producer can allocate the weight of each objective, and reduce the carbon emissions in the production process on the premise of ensuring the balance of the completion time and equipment utilization.
Innovation in Computer Application Courses in Higher Vocational Education in the Context of Big Data
Authors: Shang Jing
Published: July 2020

In the context of the current big data era, the conventional classroom teaching is inadequate for the demand of computer application courses in higher vocational education. The way to reform the teaching mode, teaching method and teaching resources, and to integrate big data technology into computer application course teaching is explored, in order to train and educate talents at the demand of the developing times.
The Comparison of Retinal Vessel Segmentation Methods in Fundus Images
Authors: Luo Zhongliang , Jia Yingbiao
Published: July 2020

Due to complexity of retinal fundus images, they are usually affected with noise and lighting during image acquisition. It brings difficulty to segment retinal vessels accurately, so accurate retinal vessel segmentation is still a challenging task in fundus images analysis. Five kinds of typical retinal vessel segmentation methods are briefly introduced in this paper, which are based on thresholding, matched filtering, mathematical morphology, tracking, and deep learning. Each method has its own characteristics. The experiment results show that the method based on deep learning is the best segmentation method among them, which can effectively assist doctors to detect and diagnose cardiovascular and ophthalmic diseases in early stage, and provide the decision support for ophthalmic disease computer-aided diagnosis and establishment of large-scale screening system.
Research and Prospect of Image Recognition Based on Convolutional Neural Network
Authors: Hu Hanqing , Lyu Jin , Yin Xiaolin
Published: July 2020

This paper compares common image recognition technology, introduces three image recognition and classification technologies, and explains the most popular deep learning image recognition algorithm based on CNN in detail. As a new method of ANN, CNN combines ANN and deep learning technology. In the area of image recognition, the advantage of CNN is particularly prominent. Compared with the traditional image processing algorithm, CNN has higher recognition accuracy and speed, and can directly process the original image to avoid the complicated pre-processing image data. CNN is the first choice for image recognition.
Consulting Scheduling of Vocational Planning in Colleges and Universities Based on Improved Genetic Algorithms
Authors: Chen Zhenyu
Published: July 2020

In the work of promoting vocational planning education and consultation in colleges and universities, there are some problems, such as fewer teachers and more students, will make it difficult to complete the consultation for all students in a limited time. Focusing this problem, this paper makes a research on consulting scheduling of vocational planning in colleges and universities based on an improved genetic algorithms (IGA). Firstly, an improved genetic algorithm (IGA) is proposed in combination with the characteristics of the problem, which can realize the full coverage of the student consultation as soon as possible under the reasonable consideration of the workload and consultation time of the consultation teacher. The problem is coded by double-string method, different genetic operators are used for different characteristics of the string, and enhanced search operation is introduced to strengthen the optimal individual in the population. The results show that the IGA is more accurate and stable than the traditional genetic algorithm for promoting vocational planning education and consultation. The effectiveness of the improved strategy is verified by a simulation test. It is a feasible and reasonable scheduling algorithm for allocating consultation resources.
Capability of Sentinel-1 Synthetic Aperture Radar polarimetric change detection for burned area extraction in South Kalimantan, Indonesia
Authors: Syam’ani
Published: July 2020

Burned area extraction from optical imageries often has a major problem, that is the presence of atmospheric particles. A potential alternative for burned area extraction is using SAR imageries, those are relatively free of atmospheric interference. The purpose of this research was to explore change detection capabilities of Sentinel-1 SAR polarimetry for burned area extraction. The imagery used is dual-polarized Sentinel-1 (VV,VH). A number of polarimetric transformation methods are applied for the purpose of change detection. Those are, single cross-polarized log ratio, single co-polarized log ratio, dual polarized combination log ratio, dual polarized multiple log ratio, and dual polarized ratio log ratio. For comparison, the Relativized Burn Ratio (RBR) method was applied to the Sentinel-2 MSI imagery. The Otsu thresholding is then applied to separate the burned area and the unburned area. The results of the research showed that the single cross-polarized log ratio (ln(σ0VHt1/σ0VHt2)) transformation method was the most accurate method. This method has an overall accuracy of 88.7665% (Kappa 0.7567). It is more accurate than Sentinel-2 RBR, which has an overall accuracy of 81.8470% (Kappa 0.6383). Cross validation between Sentinel-1 SAR change detection and Sentinel-2 RBR does not show a significant correlation. The highest correlation coefficient achieved is only 0.25. This shows that burned area extraction between change detection from SAR imageries and RBR from optical imageries has a different mechanism. SAR change detection tends to detect changes in surface roughness, while NIR-based RBR tends to extract changes in leaf chlorophyll conditions.
Deformation and instability at Merapi dome identified by high resolution camera
Authors: Darmawan Herlan , Yuliantoro Pamungkas , Suryanto Wiwit , Rakhman Afif , Budi Santoso Agus
Published: July 2020

After phreatic eruptions in May and June 2018, a new dome continuously grows and deforms at Merapi summit. The growth of the Merapi dome progressively causes over steepening, triggers gravitational instability, and then collapses, producing pyroclastic flow. These activities have been observed by our high-resolution camera. Here, we performed high resolution terrestrial photogrammetry to identify deformation and instability at the Merapi dome. The data were collected between 10 and 15 April 2019 by using Cannon EOS 60 D camera and equipped with 200 mm lens. The 200 mm tele lens is able to provide detail morphology and to identify deformation up to sub meter accuracy. The high-resolution images were processed by registering a slave image to a reference image, scaling the images, and applying pixel-tracking techniques. The technique is able to identify deformation of the Merapi dome. Results show a continuous deformation with mean displacement of ∼1m during that period. A strong deformation was identified at the south-eastern part of the dome with maximum displacement up to 5 m which might be associated with a dome collapse that produced pyroclastic flow on 10 April 2019. Based on our observation, we infer that the activities of dome growth and gravitational instability triggers dome collapse are recently dominant at Merapi volcano.
Detecting mangrove deforestation using multi land use land cover change datasets: a comparative analysis in Southeast Asia
Authors: Sudhana Sonny A. , Sakti Anjar D. , Syahid Luri N. , Prasetyo Lilik B. , Irawan Bambang , Kamal Muhammad , Wikantika Ketut
Published: July 2020

Mangrove forest grows on tropical coastal areas and has an ecological role for its surrounding environment. Mangrove forest protects the coast from large waves and becomes a habitat for various marine fauna. It stores the highest densities of carbon among any other ecosystem globally. In Southeast Asia, Mangrove forest is highly biodiverse and contributes to the sustainability of the ecosystem. However, based on previous studies, mangrove forests are experiencing deforestation due to high demands of commodities and land use. In this study, we analyzed changes of land cover in Southeast Asia using several global land cover products produced between 2001 and 2012 and their correlation with mangrove deforestation based on Mangrove Forest Watch (CGMFC-21) data. LULC data products applied in this study were ESA CCI LC, MODIS LC, GlobCover. The analysis was carried out by calculating the rate of increase in mangrove deforestation and comparing it with changes in land cover that replaced the mangrove area temporally. The results of this study were land cover classes that replaced mangrove forest areas in the study period. Based on the results it could be concluded that the methods and products used influence the results. There are many sources of data products that might be used for future research, with other methods that are better so that they provide space for future research and development. Our study can be used as a consideration to implement policies that conserve mangrove forest across Southeast Asia.
Towards a study of fire occurrences in Indonesia
Authors: Susandi Armi , Tamamadin Mamad , Wijaya Aristyo R. , Pratama Angga F. , Faisal Irvan , Pratama Alvin , Widiawan Destika A.
Published: July 2020

In the past 5 years, the issue of forest and peatland fires in Indonesia has received a major concern from various parties. As one of the prevention efforts, the Government of Indonesia seeks to prevent the ignition of forest and peatland fires both anthropogenic and naturally as a result of prolonged drought. These efforts could be carried out well through the implementation of remote sensing observations and through predictive technology on the position of the hotspot. However, it should be noted that historical data that have been used in those predictive technology on these hotspots are not yet verified and validated with fire occurrences and burned area footprints. Therefore, in this study, verification of historical fires hotspot will be conducted with the occurrence of wildfires based on land use satellite imagery to validate the events. This verification test will use overlay and spatial statistical methods. based on the results of the verification test, a number of hotspots were found that were not in accordance with the incidence of forest fires especially in some area that neared agricultural area and factories. Thus, in the implementation of the use of hotspot data for predictions of forest fires, it is necessary to verify the suitability of the land and the incidence of forest fires.
Spectral analysis for phenological studies of leaves and fruits development in coffee plantation in Gunung Puntang: a preliminary result
Authors: Ghazali M F , Wikantika K , Tridawati A , Harto A B
Published: July 2020

This is important to know plant health that affects fruits production. Especially in a coffee plantation, even though it will be dried before harvesting, the farmers depend on their fruits and only the mature will be taken. The biochemical parameters in leaves and coffee fruits will be defined as the major factors in determining plant health. Both leaf and fruit coffee’s reflectance used to determine biochemical content during its development stages. Some of modification vegetation indices that used to evaluate the greenness level, chlorophyll and water content, and colorization named MNDVI, MCARIs, MNDWI and MYI and the associated indices with all parameters name REPD was used to understand the leaves development. The result shows that all leaves biochemical factors are decreased during its development. All factors also shown a moderate to strong relationship each other. The highest correlation is given by the water content based on the estimated values of MYI. It has R2 -0.96 to the values of REPD. Since the REPD capable to control the values of MNDVI, MCARIs, and MNDWI with R2 -0.91, -0.66 and -0.71 respectively.
Google earth engine application for estimating changes in water surface area of Lake Toba
Authors: Aziz F , Kusratmoko E , Manessa M D M
Published: July 2020

The change in the water surface area is essential to be studied as it can affect ecosystem health and function of lakes to meet human needs. The use of remote sensing techniques is to analyze such changes in the Lake Toba is considered effective and efficient ways in terms of time and cost, moreover the application of Google Earth Engine (GEE) as an internet-based data processing platform (cloud computing) that provides various kinds of free satellite image data can simplify the process. In this study, the author aims to estimate the rate of change in the surface water area of Lake Toba in four periods, that are the period of 1990 – 1997, 1998 – 2004, 2005 – 2012, and 2013 – 2018, by using Landsat 5 TM and 8 OLI/TIRS imagery. Cloud masking methods is used to obtain cloud-free images and then using CART method in making land cover maps. After that, calculating the accuracy of CART method by using the confusion matrix to determine the Cohen’s Kappa coefficient value. The results of this study show that the highest lake surface water area is in the period of 1990 - 1997 within the area of 1133.88 km2, and the lowest one is in the periode of 1998 - 2004 within the area of 1119.20 km2. The correlation of land cover classes with a surface water area of Lake Toba shows that the open land has high correlation value of -0.77.
Karst imaging of Mangkalihat in East Kalimantan; insight from Landsat OLI 8, DEMNAS and field investigation
Authors: Agustin F. , Faturrohman M.L. , Rijani S. , Maryanto S.
Published: July 2020

Karst is one of the typical of landscape which is formed by soluble rock and mineral formation such as limestones, dolomites, gypsum, anhydrites and others types that have the same chacateristic. Based on Permen ESDM 17/2012, Karst Landform Area has two main function; conservation and development area. Mangkalihat Karst has some critical issues both on conservation and sustainable utilisation of its resources. We aim to delineate karst landform and other limestones formation in the area. Using DEMNAS-based combined with the multispectral imagery from Landsat OLI 8, we were able to delineate the karst area according to visual interpretation on karst morphology. Mangkalihat Karst presents as half-circular morphology consists of Tendehantu Hills in the west and Mangkalihat Hills in the east. The stratification of limestones formation has been clearly visible on image structured parallel strike with the arc. The slope is very steep (more than 45%) and it is densely vegetated areas. To the north, karst morphology formed undulated karst hills as slope average ranging from very steep to moderate. Scattered conical hills were identified as a result of surface karstification. However, drainage pattern had not clearly formed in karst landscape, they were formed subsurface. Tendehantu Formation (Tmt) is the main rock formation in the Mangkalihat Karst. Field investigation indicated that Tendehantu Formation (Tmt) is composed by coral limestones, white to light yellowish in color, well bedded and depsited during Middle Miocene in shallow marine (neritic zone). Caves and subsurface rivers had been identified in the area as a manifestation of endogenic and exogenic karst. The result can be approched for resource sustainability in Mangkalihat Karst Area.
Multiple linear regression analysis of remote sensing data for determining vulnerability factors of landslide in PURWOREJO
Authors: Sudaryatno  , Widayani Prima , Wibowo Totok Wahyu , Pramono Bayu Aji Sidiq , ‘Afifah Zulfa Nur’aini , Meikasari Awit Dini , Firdaus Muhammad Rizki
Published: July 2020

Purworejo is one of the potential area that could be experiencing landslides, because the geomorphological conditions which are included in Menoreh Hills are geographically sloping to very steep. Based on the Indonesian Disaster Information Data (DIBI) and the National Disaster Management Agency (BNPB) in the last five years from 2014 to April 2019 there have been 64 landslides in Purworejo. The research on landslide vulnerability mapping has been done with various spatial modeling methods, one of them is using Information Value Model (IVM). There are four landslide factors arranging the model, such as elevation, slope, slope direction and vegetation index (NDVI). The purpose of this research is to determine the most influence factors towards landslide vulnerability levels thorugh remote sensing data. Multiple regression analysis is used to determine the most influential factors. In this research, dependent variable represented by eight landslide factors, and the independent variable is vurnerability level of landslide in Purworejo. The results of this study explain that the predictor variables that most influence the occurrence of landslides in Purworejo are elevations with regression values that are quite dominant among other variables.
Application of vegetation health index (VHI) to identify distribution of agricultural drought in Indramayu Regency, West Java Province
Authors: Zuhro Asma , Tambunan Mangapul Parlindungan , Marko Kuswantoro
Published: July 2020

The drought that occurred in Indramayu Regency was caused by a shift of the beginning season and a long dry season which affected the availability of water storage for plants. Indramayu Regency is one of the rice centers in West Java with 56% of its area is rice fields. But in recent years rice productivity has been reduced due to drought. The Indramayu District Agriculture Office noted that in 2012, 2015 and 2018 paddy fields. The purpose of this study was to determine the distribution of 2012, 2015 and 2018 wetland agricultural drought areas and their relationship with rainfall in Indramayu Regency. The VHI drought index (Vegetation Health Index) is used to determine the pattern of distribution of the drought area of agricultural land. VHI is a combination of VCI (Vegetation Condition Index) and TCI (Temperature Condition Index) derived from NDVI data processing (Normalized Difference Vegetation Index), LST (Land Surface Temperature) of Landsat 7 and 8 images. The processing results of the VHI index show the distribution of drought levels no drought to extreme drought, where in 2012, 2015 and 2018 the distribution of drought in agricultural land has the same pattern, which is dominated by the coastal areas of Indramayu Regency due to the influence of less rainfall. While the level of mild drought is in the western and center regions of Indramayu Regency.
Filtering DSM extraction from Worldview-3 images to DTM using open source software
Authors: Rokhmana Catur Aries , Sastra Ahmad Ridho
Published: July 2020

Today, the Indonesia one map policy has encouraged for producing maps up to scale 1/5.000 – 1/10.000. Therefore, all efforts to accelerate large-scale map production are still needed. One of the challenges is for producing DEM (Digital Elevation Model). DEM data extraction from high-resolution optical satellite imagery is an efficient choice for the production of large-area DEM. This study uses Worldview 3 stereo ready images for DSM (Digital Surface Model) Extraction. Although the DSM data have a high resolution 30cm x 30cm, unfortunately, the DEM extraction techniques from optical images produce DSM (Digital Surface Model) data instead of DTM. While topographic maps generally use DTM data instead of DSM. So, the goal of this study is to use an appropriate procedures method in Open-Source (OS) software towards the generation of Bare-Earth data by filtering DSM. The OS software is SAGA-GIS that it is can be used for any point cloud data. The quality of DTM generated by SAGA-GIS is evaluated by visual interpretation from Worldview 3 orthoimage itself. A good filtering result will remove the non-terrain point. Some independent check point used to evaluate the error in elevation. The error in elevation still less than 2 pixels. Final product is a high resolution DTM which has 30cm × 30cm grid spacing.
Identification of soil erosion areas and soil conservation in the Ci Lutung watershed using the RUSLE method
Authors: Rivanda R A , Kusratmoko E , Rustanto A
Published: July 2020

Erosion is one of the geomorphological processes that play a role in the development of landforms. Erosion events are controlled by exogenous energy through geomorphological agents. The rate of soil erosion in each ecosystem differs depending on how strong the erosion factor affects the soil conditions. Erosion rates will be very dangerous if erosion occurs in large erosion and in large areas. This will result in disruption of human activities and harm to society. Therefore, the importance of knowing the rate of eroded land and its variables so that this can be used in developing development and so as not to cause harm to the community. The purpose of this study was to map the area of soil erosion that occurred in Ci Lutung watershed and how big the erosion was and to find out how effective soil conservation was carried out on erosion occurring. In this study using the RUSLE (Revised Universal Soil Loss Equation) method as an equation to determine the amount of erosion and the incidence of erosion at Ci Lutung watershed. The results showed that Ci Lutung watershed’s erosion incidence was dominated by mild but extensive erosion events and the impact of severe erosion events could affect human activities.
Identification of photo number effect for 3D modeling in Agisoft software
Authors: Maharani Monica , Charieninna Anna , Nugroho Hary
Published: July 2020

At present, photogrammetry projects, including Close-Range Photogrammetry, has been supporting by software that works automatically. Agisoft Metashape is one of the Close-Range Photogrammetry data processing software that can work automatically. In accordance with ISPRS recommendations, the success of Close-Range Photogrammetry processing is determined by the overlap in each photo. Based on ISPRS, Close-Range Photogrammetry will succeed if each photo has an overlap of 90-95%. In line with ISPRS, Agisoft always recommends users to input more than enough photos in each processing, where more photos will produce better results. These conditions will make the number of photos used in Close-Range Photogrammetry processing will be very large, very long time processing and the processors required must be highly certified. This paper will analyze the photo number effect for 3D modeling in Agisoft software, as well as prove whether large overlapping values and a large number of photos will increase the accuracy of the resulted model. There are three simulations of photo number will be compared in terms of geometric quality, while the suitability of the resulting 3D model will also be discussed. Furthermore, the detection of causes failure in one simulation of photo number will also be explained in this paper. Results show that a large number of photos did not produce a better 3D model, so to create a 3D model does not require a large number of photos but the optimal number.
Remote sensing image transformation with cosine and wavelet method for SPACeMAP Visualization
Authors: Gumelar O , Saputra R M , Yudha G D , Payani A S , Wahyuningsih S D
Published: July 2020

Remote sensing imagery in LAPAN has been managed and distributed through many media and device, like CCT, DCRSy, tape, CD, DVD, hard drive. The format is available from Quicklook data (in JPG or BMP), data RAW (in Gtiff or ground station data format). There also exist metadata that bring along in each remote sensing data like Landsat data, SPOT, Radar data, and High-resolution data. From that all collection then it would need some system that can arrange, keep and distribute data in a huge amount of number. Research on metadata structure and standard will be required in managing a large number of remote sensing data. Types and formats from those remote sensing data will be various but the raster format which most widely used is GeoTiff. Metadata for every raster data format is already standardized following the rule of ISO 19139 and 19115. SPACeMAP is a new web catalog system that uses the simplest and latest raster data format for displaying the mosaic image, data processing result, data raw format and etc. The structure of raster data format (like Gtiff and ECW) is very flexible although the format needs certain criteria. Metadata also treated the same as raster format, this treatment hopefully will minimize the error.
Self-crosslinking hyaluronic acid–carboxymethylcellulose hydrogel enhances multilayered 3D-printed construct shape integrity and mechanical stability for soft tissue engineering
Authors: Janarthanan Gopinathan , Shin Hyun Soo , Kim In-Gul , Ji Pyung , Chung Eun-Jae , Lee Chibum , Noh Insup
Published: July 2020

One of the primary challenges in extrusion-based 3D bioprinting is the ability to print self-supported multilayered constructs with biocompatible hydrogels. The bioinks should have sufficient post-printing mechanical stability for soft tissue and organ regeneration. Here, we report on the synthesis, characterization and 3D printability of hyaluronic acid (HA)–carboxymethylcellulose (CMC) hydrogels cross-linked through N-acyl-hydrazone bonding. The hydrogel’s hydrolytic stability was acquired by the effects of both the prevention of the oxidation of the six-membered rings of HA, and the stabilization of acyl-hydrazone bonds. The shear-thinning and self-healing properties of the hydrogel allowed us to print different 3D constructs (lattice, cubic and tube) of up to 50 layers with superior precision and high post-printing stability without support materials or post-processing depending on their compositions (H7:C3, H5:C5 and H3:C7). Morphological analyses of different zones of the 3D-printed constructs were undertaken for verification of the interconnection of pores. Texture profile analysis (TPA) (hardness (strength), elastic recovery, etc) and cyclic compression studies of the 3D-printed constructs demonstrated exceptional elastic properties and fast recovery after 50% strain, respectively, which have been attributed to the addition of CMC into HA. A model drug quercetin was released in a sustained manner from hydrogels and 3D constructs. In vitro cytotoxicity studies confirmed the excellent cyto-compatibility of these gels. In vivo mice studies prove that these biocompatible hydrogels enhance angiogenesis. The results indicate that controlling the key properties (e.g. self-crosslinking capacity, composition) can lead to the generation of multilayered constructs from 3D-bioprintable HA-CMC hydrogels capable of being leveraged for soft tissue engineering applications.
Effect of nanoclay and nanoscale TiO2 on carbon/glass fibrereinforced polymer composites
Authors: B Elamvazhudi , S Gopalakannan
Published: July 2020

Nanofillers dispersion in polymeric matrix has been identified as a novel method to enhance the mechanical properties of Fibre Reinforced Polymer Nanocomposites (FRPNCs). In general, addition of nanofillers in polymeric resin improves the fracture toughness, tensile and other properties of polymer composites. On the other hand, this inclusion significantly reduces the stiffness, strain at rupture and thermal properties. To overcome these limitations, hybrid nanofillers have been introduced in polymer composites. This work aims to investigate the effect of addition of hybrid nanofillers (Nanoclay-TiO2) on mode I interlaminar fracture toughness (GIC), tensile as well as flexural characteristics of carbon/glass/epoxy based composites. The pristine epoxy resin was modified with nanoclay and nanoscale TiO2 nanofillers together with different weight percentages (0.5, 1, 1.5 & 2 wt%) using mechanical stirrer followed by sonication process. The modified epoxy based carbon/glass polymer laminates were fabricated using hand lay-up process. The lay-up sequence considered in this study was (90 °C/90 °G/0 °G)S, (90 °G/0 °G/90 °C)S and (90 °G/0 °C/90 °G)S. The mechanical properties of modified laminates were characterized by DCB test, tensile and three point bending test. The experimental results show that the addition of hybrid nanofillers in epoxy resin increased the mode I interlaminar fracture toughness (GIC) by 77% at 1.5 wt%, tensile strength by 31% at 1.5 wt%, and flexural strength by 33% at 2 wt%. Further addition of nanofillers (<2 wt%) decrease the mechanical properties of FRPNCs as a result of matrix embrittlement. The toughening mechanisms such as fibre pull-out, fibre breaking, particles debonding, and crack deflection were identified at the fractured surfaces.
Reversible and irreversible processes during cyclic voltammetry of an electrodeposited manganese oxide as catalyst for the oxygen evolution reaction
Authors: Villalobos Javier , Golnak Ronny , Xi Lifei , Schuck Götz , Risch Marcel
Published: July 2020

Manganese oxides have received much attention over the years among the wide range of electrocatalysts for the oxygen evolution reaction (OER) due to their low toxicity, high abundance and rich redox chemistry. While many previous studies focused on the activity of these materials, a better understanding of the material transformations relating to activation or degradation is highly desirable, both from a scientific perspective and for applications. We electrodeposited Na-containing MnOx without long-range order from an alkaline solution to investigate these aspects by cyclic voltammetry, scanning electron microscopy and x-ray absorption spectroscopy at the Mn-K and Mn-L edges. The pristine film was assigned to a layered edge-sharing Mn3+/4+ oxide with Mn-O bond lengths of mainly 1.87 Å and some at 2.30 Å as well as Mn-Mn bond lengths of 2.87 Å based on fits to the extended x-ray fine structure. The decrease of the currents at voltages before the onset of the OER followed power laws with three different exponents depending on the number of cycles and the Tafel slope decreases from 186 ± 48 to 114 ± 18 mV dec−1 after 100 cycles, which we interpret in the context of surface coverage with unreacted intermediates. Post-mortem microscopy and bulk spectroscopy at the Mn-K edge showed no change of the microstructure, bulk local structure or bulk Mn valence. Yet, the surface region of MnOx oxidized toward Mn4+, which explains the reduction of the currents in agreement with literature. Surprisingly, we find that MnOx reactivates after 30 min at open-circuit (OC), where the currents and also the Tafel slope increase. Reactivation processes during OC are crucial because OC is unavoidable when coupling the electrocatalysts to intermittent power sources such as solar energy for sustainable energy production.
Analyzing mass media influence using natural language processing and time series analysis
Authors: Albanese Federico , Pinto Sebastián , Semeshenko Viktoriya , Balenzuela Pablo
Published: July 2020

A key question of collective social behavior is related to the influence of mass media on public opinion. Different approaches have been developed to address quantitatively this issue, ranging from field experiments to mathematical models. In this work we propose a combination of tools involving natural language processing and time series analysis. We compare selected features of mass media news articles with measurable manifestation of public opinion. We apply our analysis to news articles belonging to the 2016 US presidential campaign. We compare variations in polls (as a proxy of public opinion) with changes in the connotation of the news (sentiment) or in the agenda (topics) of a selected group of media outlets. Our results suggest that the sentiment content by itself is not enough to understand the differences in polls, but the combination of topics coverage and sentiment content provides an useful insight of the context in which public opinion varies. The methodology employed in this work is far general and can be easily extended to other topics of interest.
Rapid transition from oral selexipag to parenteral treprostinil in a patient with mixed-etiology pulmonary hypertension
Authors: Radosevich John J , DeChristopher Audra , Irandost Maykel , Fann Jade , Feldman Jeremy
Published: July 2020

Purpose

Selexipag is an oral nonprostanoid IP prostacyclin receptor agonist that is indicated for treatment of pulmonary arterial hypertension (PAH). In patients with continued symptoms of PAH despite maximized oral therapy with selexipag and other oral therapies, a transition to parenteral prostacyclin may be warranted. There is a paucity of data regarding how to safely transition from oral selexipag to parenteral treprostinil. We describe rapid transition from oral selexipag to parenteral treprostinil in this case report.

A 65-year-old female with mixed-etiology PAH as result of pulmonary fibrosis related to polymyositis was admitted to the intensive care unit to be transitioned from selexipag to treprostinil due to dyspnea at rest despite therapy with selexipag 1,600 mg twice daily and macitentan 10 mg daily for 3 years. At baseline the patient required oxygen support (4 L/min) at rest to maintain oxygen saturation at or above 90%. Right heart catheterization performed 8 weeks prior to admission revealed severe PAH, with a pulmonary arterial pressure of 73/27 mm Hg and pulmonary vascular resistance of 10 Wood units. On the day of admission the patient was given selexipag 800 µg at 9 am and simultaneously started on intravenous (i.v.) treprostinil at a dose of 2 ng/kg/min. The treprostinil dose was increased by 2 ng/kg/min every 3 hours until a target dose of 22 ng/kg/min was achieved, at which point the patient had experienced dyspnea improvement. She experienced a mild headache and flushing during rapid treprostinil dose escalation. After 30 hours of i.v. treprostinil infusion, the patient was transitioned to subcutaneous treprostinil therapy and discharged.

Conclusion

In this case the patient was rapidly transitioned from oral selexipag to i.v. and then subcutaneous treprostinil therapy over a 30-hour period, with minimal adverse effects.
Vertical integration methods for gene expression data analysis
Authors: Wu Mengyun , Yi Huangdi , Ma Shuangge
Published: July 2020

Gene expression data have played an essential role in many biomedical studies. When the number of genes is large and sample size is limited, there is a ‘lack of information’ problem, leading to low-quality findings. To tackle this problem, both horizontal and vertical data integrations have been developed, where vertical integration methods collectively analyze data on gene expressions as well as their regulators (such as mutations, DNA methylation and miRNAs). In this article, we conduct a selective review of vertical data integration methods for gene expression data. The reviewed methods cover both marginal and joint analysis and supervised and unsupervised analysis. The main goal is to provide a sketch of the vertical data integration paradigm without digging into too many technical details. We also briefly discuss potential pitfalls, directions for future developments and application notes.
RTExtract: time-series NMR spectra quantification based on 3D surface ridge tracking
Authors: Wu Yue , Judge Michael T , Arnold Jonathan , Bhandarkar Suchendra M , Edison Arthur S
Published: July 2020

Motivation

Time-series nuclear magnetic resonance (NMR) has advanced our knowledge about metabolic dynamics. Before analyzing compounds through modeling or statistical methods, chemical features need to be tracked and quantified. However, because of peak overlap and peak shifting, the available protocols are time consuming at best or even impossible for some regions in NMR spectra.

Results

We introduce Ridge Tracking-based Extract (RTExtract), a computer vision-based algorithm, to quantify time-series NMR spectra. The NMR spectra of multiple time points were formulated as a 3D surface. Candidate points were first filtered using local curvature and optima, then connected into ridges by a greedy algorithm. Interactive steps were implemented to refine results. Among 173 simulated ridges, 115 can be tracked (RMSD < 0.001). For reproducing previous results, RTExtract took less than 2 h instead of ∼48 h, and two instead of seven parameters need tuning. Multiple regions with overlapping and changing chemical shifts are accurately tracked.

Availability and implementation

Source code is freely available within Metabolomics toolbox GitHub repository (https://github.com/artedison/Edison_Lab_Shared_Metabolomics_UGA/tree/master/metabolomics_toolbox/code/ridge_tracking) and is implemented in MATLAB and R.

Supplementary information

Supplementary data are available at Bioinformatics online.
Too many species: morphometrics, molecular phylogenetics and genome structure of a Brazilian species complex inEpidendrum(Laeliinae; Orchidaceae) reveal fewer species than previously thought
Authors: Pessoa Edlley M , Cordeiro Joel M P , Felix Leonardo P , Almeida Erton M , Costa Lucas , Nepomuceno Álvaro , Souza Gustavo , Chase Mark W , Alves Marccus , van den Berg Cássio
Published: July 2020

In this study, we analyse a species complex in Epidendrum, a mega-diverse Neotropical orchid genus, that is formed by the 11 Brazilian species of the E. difforme group. Although this group (c. 100 taxa) exhibits relatively high levels of floral variation, the Brazilian species are similar, making delimitation problematic. Here we combine molecular (phylogenetics), morphological (geometric morphometrics), genome size and cytogenetic (chromosome counts and CMA/DAPI staining) data to investigate circumscription of these species. Our results were interpreted by looking for congruence of the results as a means to delimit species. The studied taxa appear to be monophyletic, and karyotypically all analysed accessions were 2n = 40. Their 1C values vary from 1.99 ± 07 pg to 2.84 ± 0.12 pg. We did not find evidence for recent polyploidy or dysploidy and, apparently, these phenomena have not been important in the evolution of this species complex. On the other hand, we found high levels of polymorphism for CMA/DAPI banding, and variation in genome size appears to be positively correlated with latitude. Geometric morphometrics indicate that E. sanchezii and E. anatipedium/E. amarajiense are distinct from the remaining species, and three groups of other species can be separated using canonical variables analysis (CVA). Variation in lip shape, genome size and heterochromatin patterns of the taxa are not fully congruent with the phylogenetic analysis, but our results allowed us to delimit with full confidence four species: E. amapense, E. anatipedium (including E. amarajiense), E. pseudodifforme (including E. campaccii and E. thiagoi) and E. sanchezii. Four others will be tentatively maintained but need further study. Our results indicate that it will be necessary to reassess many of the species complexes in the genus using a similar multidisciplinary perspective to evaluate the number of taxa that should be recognized.
Non-Malleable Zero-Knowledge Arguments with Lower Round Complexity
Authors: Yan Zhenbin , Deng Yi
Published: July 2020

Round complexity is one of the fundamental problems in zero-knowledge (ZK) proof systems. Non-malleable zero-knowledge (NMZK) protocols are ZK protocols that provide security even when man-in-the-middle adversaries interact with a prover and a verifier simultaneously. It is known that the first constant-round public-coin NMZK arguments for NP can be constructed by assuming the existence of collision-resistant hash functions (Pass, R. and Rosen, A. (2005) New and Improved Constructions of Non-Malleable Cryptographic Protocols. In Gabow, H.N. and Fagin, R. (eds) Proc. 37th Annual ACM Symposium on Theory of Computing, Baltimore, MD, USA, May 2224, 2005, pp. 533542. ACM) and has relatively high round complexity; the first four-round private-coin NMZK arguments for NP can be constructed in the plain model by assuming the existence of one-way functions (Goyal, V., Richelson, S., Rosen, A. and Vald, M. (2014) An Algebraic Approach to Non-Malleability. In 55th IEEE Annual Symposium on Foundations of Computer Science, FOCS 2014, Philadelphia, PA, USA, October 1821, 2014, pp. 4150. IEEE Computer Society and Ciampi, M., Ostrovsky, R., Siniscalchi, L. and Visconti, I. (2017) Delayed-Input Non-Malleable Zero Knowledge and Multi-Party Coin Tossing in Four Rounds. In Kalai, Y. and Reyzin, L. (eds) Theory of Cryptography15th Int. Conf., TCC 2017. Lecture Notes in Computer Science, Baltimore, MD, USA, November 1215, 2017, Part I, Vol. 10677, pp. 711742. Springer). In this paper, we present a six-round public-coin NMZK argument of knowledge system assuming the existence of collision-resistant hash functions and a three-round private-coin NMZK argument system from multi-collision resistance of hash functions assumption in the keyless setting.
Is obesity associated with poorer outcomes in patients undergoing minimally invasive mitral valve surgery?
Authors: Aljanadi Firas , Toolan Caroline , Theologou Thomas , Shaw Matthew , Palmer Kenneth , Modi Paul
Published: July 2020

OBJECTIVES

High body mass index (BMI) makes minimally invasive mitral valve surgery (MIMVS) more challenging with some surgeons considering this a contraindication. We sought to determine whether this is because the outcomes are genuinely worse than those of non-obese patients.

METHODS

This is a retrospective cohort study of all patients undergoing MIMVS ± concomitant procedures over an 8-year period. Patients were stratified into 2 groups: BMI ≥ 30 kg/m2 and BMI ˂ 30 kg/m2, as per World Health Organization definitions. Baseline characteristics, operative and postoperative outcomes and 5-year survival were compared.

RESULTS

We identified 296 patients (BMI ≥30, n = 41, median 35.3, range 30–43.6; BMI <30, n = 255, median 26.2, range 17.6–29.9). The groups were well matched with regard to baseline characteristics. There was only 1 in-hospital mortality, and this was in the BMI < 30 group. There was no difference in repair rate for degenerative disease (100% vs 96.3%, P > 0.99 respectively) or operative durations [cross-clamp: 122 min interquartile range (IQR) 100–141) vs 125 min (IQR 105–146), P = 0.72, respectively]. There were only 6 conversions to sternotomy, all in non-obese patients. There was no significant difference in any other perioperative or post-operative outcomes. Using the Kaplan–Meier analysis, there was no significant difference in 5-year survival between the 2 groups (95.8% vs 95.5%, P = 0.83, respectively).

CONCLUSIONS

In patients having MIMVS, there is insufficient evidence to suggest that obesity affects either short- or mid-term outcomes. Obesity should therefore not be considered as a contraindication to this technique for experienced teams.