bluuebunny/crossref_metadata_2025 huggingface dataset:
Operation optimization analysis of 600 MW steam turbine under new situation
Authors: Liu Jinliang , Zhang Yuanshu , Qi Junfeng
Published: June 2022

It is of great significance to study the operation optimization of thermal power units under the new situation and the economic operation under low load. The bearing vibration of a 600 MW thermal power unit has been too large since it was put into operation, and steam distribution optimization and sliding pressure optimization were not carried out since the unit was put into operation. In order to solve the vibration hidden trouble of the unit and explore the energy saving potential, the operation optimization test of the steam turbine is carried out. When the valve sequence is changed from GV1/2-GV4-GV3 to GV2/3-GV1-GV4, the maximum vibration of #2 bearing decreases from 150-170 μm to 50-60 μm, and the maximum vibration of #1 bearing decreases from 90-100 μm to 30-40 μm. After optimization of steam distribution, the regulating characteristics of the unit are improved obviously, and the gap between the equivalent main steam flow feedback and the ideal value of the overall flow characteristics of the sequential valve decreases from 15.20% to less than 1%, and the load and valve of the unit change steadily in the process of switching between single valve and sequential valve. Five load conditions were carried out in the sliding pressure optimization test, and the sliding pressure curves were obtained when the back pressure was 3.35kPa, 4.9kPa and 7.95kPa. After optimized operation, the coal consumption of thermal power unit is reduced by 1.47g/(kW⋅h) on average.
High Precision Manufacturing Technology of Complex Lightweight Integral Panel of Spacecraft
Authors: Liu Shufen , Zhang Bin , Zhang Hengyi , Yi Zhuoxun , Lai Xiaoming , Yang Kai
Published: June 2022

For the problem that the traditional manufacturing method of spacecraft integral panel can not meet the manufacturing precision of the complex lightweight integral panel of the new generation of spacecraft, a method of roll bending in the state of flat plate first and then machining the grid features of the outer surface is proposed. ANSYS is used to simulate and analyze the internal stress when the integral panel with different roll bending radius when fitting with the tooling. It is obtained that it is easier to realize clamping and bonding by controlling the roll bending radius of the integral panel according to the negative difference. The clamping and positioning of the integral panel with vacuum adsorption device and the machining with variable helix angle milling cutter can effectively reduce the machining vibration. Combined with the processing compensation based on detection, the problem of out of tolerance of wall thickness in processing is solved, and finally the consistency of wall thickness is guaranteed. The experimental results show that this method can control the wall thickness of the integral panel within 1.05~1.33mm.
Three-dimensional cell culture approach for in vitro immunization and the production of monoclonal antibodies
Authors: Engel Robert , Micheel Burkhard , Hanack Katja
Published: June 2022

The generation of monoclonal antibodies using an in vitro immunization approach is a promising alternative to conventional hybridoma technology. As recently published, the in vitro approach enables an antigen-specific activation of B lymphocytes within 10–12 d followed by immortalization and subsequent selection of hybridomas. This in vitro process can be further improved by using a three-dimensional surrounding to stabilize the complex microenvironment required for a successful immune reaction. In this study, the suitability of Geltrex as a material for the generation of monoclonal antigen-specific antibodies by in vitro immunization was analyzed. We could show that dendritic cells, B cells, and T cells were able to travel through and interact inside of the matrix, leading to the antigen-specific activation of T and B cells. For cell recovery and subsequent hybridoma technique the suitability of dispase and Corning cell recovery solution (CRS) was compared. In our experiments, the use of dispase resulted in a severe alteration of cell surface receptor expression patterns and significantly higher cell death, while we could not detect an adverse effect of Corning CRS. Finally, an easy approach for high-density cell culture was established by printing an alginate ring inside a cell culture vessel. The ring was filled with Geltrex, cells, and medium to ensure a sufficient supply during cultivation. Using this approach, we were able to generate monoclonal hybridomas that produce antigen-specific antibodies against ovalbumin and the SARS-CoV-2 nucleocapsid protein.
Observational constraint of process crop models suggests higher risks for global maize yield under climate change
Authors: Yin Xiaomeng , Leng Guoyong
Published: June 2022

Projecting future changes in crop yield usually relies on process-based crop models, but the associated uncertainties (i.e. the range between models) are often high. In this study, a Machine Learning (i.e. Random Forest, RF) based observational constraining approach is proposed for reducing the uncertainties of future maize yield projections by seven process-based crop models. Based on the observationally constrained crop models, future changes in yield average and yield variability for the period 2080–2099 are investigated for the globe and top ten producing countries. Results show that the uncertainties of crop models for projecting future changes in yield average and yield variability can be largely reduced by 62% and 52% by the RF-based constraint, respectively, while only 4% and 16% of uncertainty reduction is achieved by traditional linear regression-based constraint. Compared to the raw simulations of future change in yield average (−5.13 ± 18.19%) and yield variability (−0.24 ± 1.47%), the constrained crop models project a much higher yield loss (−34.58 ± 6.93%) and an increase in yield variability (3.15 ± 0.71%) for the globe. Regionally, the constrained models show the largest increase in yield loss magnitude in Brazil, India and Indonesia. Our results suggest more agricultural risks under climate change than previously expected after observationally constraining crop models. The results obtained in this study point to the importance for observationally constraining process crop models for robust yield projections, and highlight the added value of using Machine Learning for reducing the associated uncertainties.
Comparison of decomposition and adaptation capability of indigenous peat cellulolytic microorganisms
Authors: Hafif B , Sasmita K D , Khaerati  , Wibowo N A
Published: June 2022

Cellulolytic microorganisms play an essential role in the weathering of lignocellulosic materials. An experiment conducted was to study the potential of indigenous peat cellulolytic microorganisms to decompose peat and adapt to life outside the peat ecosystem. Indigenous cellulolytic bacteria of peat, Comamonas testosteroni, and Delftia lacustris, and indigenous cellulolytic fungi of peat, Penicillium singorense, Aspergillus aculeatus, and Trichoderma sp. were tested their capability for that case. In a greenhouse, each cellulolytic bacteria and fungi colony inoculated to the peat were as treatments and peat without inoculation as control. The study also tested their adaptability to grow in media outside the peat, such as charcoal and zeolite mixed with processed coffee and cacao residue in Lab. The cellulolytic fungi were a little stronger than cellulolytic bacteria in peat decomposition. The fungi reduced the organic C of peat by 13.9%, while the bacteria were only 6.4%. The CO2 flux from peat inoculated by fungi colony, 0.68 mg CO2/kg peat, and by bacteria colony, 0.64 mg CO2/kg peat. Both microbes adapted to the environment outside of peat, especially charcoal and zeolite mixed with coffee and cacao residue. However, cellulolytic bacteria were more robust than cellulolytic fungi if living simultaneously in the same media.
Water, Food, and Energy Nexus in Lampung Province, Indonesia
Authors: Anika N. , Ramadhani D. A. , Wijaya L. , Azizah I. N. , Mahardika M. , Fauzi A. I. , Bindar Y.
Published: June 2022

Lampung Province’s population growth rate has increased in recent decades. Population growth and mobility increase the need for water, energy, and food (WEF). Hence, maintaining food security, water consumption in the agricultural sector, and energy consumption have all been considered sustainable development. The potential of the three critical sectors can be increased using the nexus approach by taking into account several factors such as availability, accessibility, resource quality to generate positive synergies and effectively manage losses. The Nexus approach enhanced complex systems’ decision-making and responded to system shocks. Furthermore, it was used to identify and eliminate contradictory policies required to achieve integrated and coherent policies that address interconnected resource sectors. WEF Nexus approaches must comprehend how the governed’s trade-off and resource use efficiency affects outcomes in terms of social equity, externalities, and socio-ecological resilience. Based on WEF analysis for Lampung Province, water security is a significant factor for food and energy security, while water availability is in high vulnerability in the dry season due to lack of water resources infrastructure and catchment area degradation.
The Study of Shallot Seedling from TSS (True Shallot Seed) on LCAC (Low-Cost Aeroponic Chamber)
Authors: Amarillis S , Solahudin M , Sucahyo L
Published: June 2022

True Seed Shallot (TSS) is the planting material beside bulbs that farmers in Indonesia have used. TSS give some benefit for farmer technically and economically. However, the farmer’s utilization of TSS is not used widely yet because there are constraints on the provision of shallot seeds from TSS, such as low seed growing percentage and seedling performance. This study aims to obtain the best seedling performance of shallot from TSS with LCAC (Low-Cost Aeroponic Chamber) technology. The experiment was conducted at the Plant Factory and Screen House, Leuwikopo, Department of Mechanical and Biosystems Engineering, IPB University, July to October 2021. The germination was carried out for seven days. After that, the shallot seedlings have given light source treatments. The factor was light sources, i.e., screen house (sunlight; as a control; used wick system hydroponic), white light, red-blue light, and custom light (LED in a controlled room with LCAC). The performance shallot seedling on sunlight source treatment gave the average plant height, the number of leaves higher than white, red-blue, and custom light on 3 and 4 weeks after sowing. The white light treatment gave the chlorophyll-a, chlorophyll-b, and total chlorophyll-a & b higher than the other light source treatments.
Cultivation Technology for Drought Stress Mitigation in Tea Plants: A Review
Authors: Rokhmah D N , Astutik D , Supriadi H
Published: June 2022

Tea is one of the beverage crops that has a high-value economy and opportunities to increase its production. The yield and quality of the tea plants are strongly affected by environmental conditions. Global warming is followed by climate change, resulting in changes in rainfall patterns and an increase in air temperature. Changes in rainfall patterns affect drought, namely the occurrence of 3 consecutive dry months. The air temperature has increased over the last 100 years. The air temperature on the earth’s surface has increased by an average of 0.74°C. Shifting climatic conditions as a result of climate change can cause the growth and yield of tea plants to be disrupted. Tea plants can suffer from temporary wilting, chronic wilting, leaves falling off, drying shoots and young branches, and the death of twigs, main branches, and stems as a result of prolonged dryness. Drought caused damage to tea plants, resulting in a 53% decrease in yield. To overcome this, cultivation technology can be used in the following ways: (1) planting tolerant clones; (2) fertilization; (3) mulching and planting shade trees; (3) pruning; and (4) rainwater harvesting and irrigation systems.
The Potential of Sustainable Biogas Production from Macroalgae in Indonesia
Authors: Farobie Obie , Syaftika Novi , Hartulistiyoso Edy , Amrullah Apip , Bayu Asep , Moheimani Navid R , Matsumura Yukihiko , Karnjanakom Surachai
Published: June 2022

Indonesia is the second world’s major macroalgae producer after China, contributing to 28% of the global macroalgae production. Indonesia increased its macroalgae farming output from less than 4 million tons in 2010 to over 9.9 million tons in 2019. It is expected to continue rising to 13 million tons by 2024. The contribution of macroalgal products is quite significant, 60.7% of the total national aquaculture production. To achieve sustainable energy development goals in many developing countries, including Indonesia, biomass to energy technology such as the production of biogas form macroalgae has been considered one of the best options. Therefore, we aim to investigate the potential application of biomass to energy technology via the production of biogas from macroalgae as an alternative source of local power generation. Indonesia’s energy mix and several issues regarding macroalgae production are comprehensively reviewed. Additionally, we also discussed the process of macroalgal biogas production.
Performance test of the biomass furnace for bed dryer using various of agriculture wastes
Authors: Putra I R , Safruloh G , Frisdan Z , Karyadi J N W , Purwantana B , Telaumbanua A N , Ayuni D
Published: June 2022

Waste from plantation products has the potential to be used as an alternative fuel. Corn drying needs to be done to increase the selling price of the product and shelf life. One of the drying technologies is to use a bed dryer with the heat source coming from a biomass-fueled furnace. This study aims to determine the rate of heat transfer and analyze the efficiency of the furnace. This study was conducted at the Food and Postharvest Engineering Laboratory of FTP UGM as a tool design site, PT. Raja Pengering as a tool fabrication site, and in the Sukolilo Pati area as a tool testing site. The method used is direct testing with two variations of treatment, namely when the furnace is without a load and when the furnace is with a load. Variations of biomass fuel were carried out with teak wood, corn cobs, and rice husks of 10 kg each with one replication during the no-load furnace test. The main equipment used is a furnace with a vertical tube bank-type heat exchanger and an axial blower. The test results show the value of the heat transfer coefficient when the furnace is without a load of 142.59 W/m2.K, when the furnace is with a load of 138.74 W/m2.K. The coefficient of the furnace with the load is smaller because there is a load on the bed dryer so that the speed of air flowing in the tube bank is restrained. The heat transfer rates with wood, cob, and husk fuel are 22.5; 22; and 4.7 kW, respectively. The total energy of the furnace during combustion using wood, cob, and husk fuels were 83484.7; 33718.37; and 16125 kJ, respectively. The efficiency obtained with wood, cob, and husk fuels was 44.17; 32.67; and 11.65 %, respectively. The husks do not match the furnace design. The performance of the furnace with a load is that the average exit temperature of the furnace is 67.69°C with an efficiency of 68.87 %. Based on the results, the appropriate fuel is wood because it has a high calorific value so which produces an optimum temperature.
Assessment of potential for adoption of wireless sensor network technology for irrigation water management of high value crops in the Philippines
Authors: Panaligan N A P , Aringo M Q , Ella V B
Published: June 2022

This study assessed the potential for adoption of wireless sensor technology (WSN) technology for irrigation water management of high value crops in the Philippines through market survey with farm owners and farm managers as respondents. Surveys were conducted in various regions in the country using non-random sampling methods. The survey basically includes questions about farm information, problems related to water management, familiarity with WSN, and willingness to adopt, among others. Based on the results, 83% of the respondents expressed willingness to adopt the WSN technology if properly demonstrated and if it will give a high return on investment. On the other hand, 76% of the respondents are willing to adopt WSN regardless of the costs provided there is a high return on investment. However, only a little more than half of the respondents are willing to adopt the WSN technology for the sake of modernization. Results also showed a strong potential for adoption of WSN technology using locally-developed sensors with 81% of the respondents providing affirmative answers. Chi-square test results indicated that sex, gross annual household income, membership to farmer’s association, land tenure status, and familiarity with WSN technology are the primary determinants of the potential for adoption regardless of the conditions imposed. However, educational attainment also played a role in the adoption of WSN technology if the purpose is agricultural modernization and if there is a higher return on investment despite some budgetary allocation for the initial costs. Results of this study could serve as a basis for developing commercialization schemes, strategies for upscaling and for agricultural policy formulation.
Development of mobile application for wireless sensor networks for efficient irrigation water management
Authors: Agulto E S , Ella V B
Published: June 2022

The evolution of smart phones has necessitated the development of mobile applications designed to perform a wide variety of functions. In the field of agriculture, mobile applications are currently used to monitor environmental parameters such as ambient temperature, humidity, soil moisture, water level, among others. A mobile application intended to monitor irrigation-related parameters and to control solenoid valves for irrigation automation was developed in this study. The mobile application was written using Flutter software development kit, and the Dart programming language. The mobile application communicates with the cloud server using a REST API written in JavaScript. The data acquired from the cloud server are presented as the current sensor reading and graphs. On the other hand, the mobile application controls the solenoid valves by sending designated bytes of data to the cloud server. The mobile application developed in this study was designed to be integrated with both low-cost sensors and the Smartmesh IP sensors to enable real-time monitoring and data visualization, and facilitate irrigation scheduling and manual irrigation control. The mobile application developed in this study may be used for efficient irrigation water management of upland crop production systems and for agricultural modernization in the Philippines and other developing countries.
Performance of structure-from-motion approach on plant phenotyping using images from smartphone
Authors: Chong J E , Harith H H
Published: June 2022

In recent years, 3D geometry has become increasingly important for plant phenotyping. The purpose of this study is to assess the measuring accuracy of a photogrammetric method based on SfM-MVS using a series of images captured by smartphone. Butterhead lettuce and the rubber plant were the two different plants used in this study. For each single plant, the images were captured from multiple views. A photogrammetry software took image input and converted them into 3D point cloud. Finally, the plant height was computed from the point cloud. Comparing the computed values to the actual values, the RMSE of the plant height was 0.28 and 0.43 for butterhead lettuce and the rubber plant, respectively. A correlation of R2 ≥ 0.94 to the reference measurement demonstrated that the photogrammetric approach is well suited for evaluation of the plant. The proposed method is simple and cost-effective by using a readily accessible device and software to reconstruct a point cloud model.
Identification of urban sprawl phenomenon and its implications in the City of Yogyakarta Province of Special Region of Yogyakarta
Authors: Anggit N B , Putri I S
Published: June 2022

Urban sprawl is a random urban expansion that causes productive land to decrease, change the shape of the city, or irregular morphology of the city. The paper aims to identify the phenomenon of urban sprawl and its implications that occur in the City of Yogyakarta. The methods used are descriptive analysis and spatial analysis through secondary data. The results of this paper include the symptoms or characteristics of urban sprawl found in the City of Yogyakarta, from 14 subdistricts there are 3 subdistricts that have a high potential urban sprawl namely Wirobrajan, Mantrijeron and Kotagede subdistricts. This paper also describes the identification of urban sprawl in City of Yogyakarta based on existing characeristics. It is based on the CBD map found in this study. Furthermore, the implications that occur cause some urban problems such as narrowing of land, high population pressure, change of land use from agricultural land to residential land and shops, land support capacity and declining availability, increased population migration, increased urbanization rate, soaring land invention prices, development projects that are increasingly spreading and developing economic and industrial centers.
Design of ‘ready-to-pack’ deep frying machine
Authors: Pratomo H , Ichniarsyah A N , Purboningtyas T P
Published: June 2022

Food processing by applying high temperatures can eliminate most microbes and inactivate enzymes that can cause spoilage. Food processing tools and machines have an important role to provide better quality results and carried out more efficiently and effectively. This study aimed to obtain and analyze data also to create design documentation for a ‘readyto-pack’ deep frying machine. Data were collected by means of observation, interviews, and documentations. Data analysis was carried out by processing the collected data with mathematical calculations. The design documentation process was done using Solidworkss software. This ‘ready-to-pack’ deep frying machine had been successfully designed and was expected to facilitate the frying process and simultaneously proceed with the spinning process. This machine was designed to use a 0.373 kW motor, constructed from stainless steel and angle bars and hollows. The analysis results of the shaft planning data at a minimum diameter of 9.06 mm and the use of 25 mm-diameter shaft were declared safe with a stress analysis on the frame of 1.065 x 107 N/m2 which was still below its maximum stress. Therefore, the machine could be constructed based on this design and analysis
Postural analysis in design evaluation of oil palm loose fruits collector machine
Authors: Saulia L , Subrata I D M , Yusuf M M
Published: June 2022

The level of maturity and the harvesting process for oil palm bunches allows some fruit to be detached from the bunch. Fruit that is separated from the bunch is called loose fruit. The loose fruit must be collected to reduce post-harvest losses. The ERBRON-C machine has been designed to facilitate the process of picking loose fruit, but further study is needed regarding its working system as an interaction between the machine and its operator. This study aimed to determine the level of risk of working posture in loose fruit collection using ERBRON-C. This research was conducted by collecting anthropometric data, recording the subject’s posture, evaluating posture using the REBA method. The results of the posture evaluation showed REBA scores ranged from 2 to 5 which refers to a low to moderate risk level.
Performance Comparison of the Implementations of Single Row Power Weeder (Single Engine) and Multi-Row Power Weeder (Twin-Engine) in Rice Fields
Authors: Telaumbanua M , Witaningsih  , Lanya B , Haryanto A , Suharyatun S , Wisnu F K
Published: June 2022

Weeding rice weeds is done to reduce and prevent the competition of nutrients absorption between weeds/grass and rice plants. Weed control can be applied through various techniques, including pulling and piling the weeds into the soil. Weeds buried in the soil can be decomposed and become nutrients for rice plants. One application of technology used in weeding weeds is the use of single row power weeder (single engine) and multi-row power weeder (twin-engine). The research aimed to compare the performance of using a single row power weeder (single engine) and a multi-row power weeder (twin-engine) in rice fields. The multi-row power weeder was designed by combining a single row power weeder. This research was conducted by testing the performance of the power weeder in rice fields in an area of 14 m x 4 m for each replication. The total area of land used was 560 m2 with five experimental replicates. Weeding activities were carried out on rice plants aged 30 DAP. The results showed a successive comparison between the performance of the single row power weeder (single engine) and the multi-row power weeder (twin-engine), such as the theoretical working capacity was 0.037 ha/hour and 0.054 ha/hour, effective working capacity was 11.11 minutes and 9.78 minutes, the efficiency of the weeder performance was 82.48% and 64.87%, fuel consumption was 1.07 liters/hour and 1.92 liters/hour, and the success rate of weeding was 64.41 % and 59.77 %. The calculation results of the plant damage levels were 15 plants and 31 plants, while the mudding index values were 75.26% and 77.62%. The results of this study showed that the advantages of using a single row power weeder were on the parameters of effective working capacity, weeding efficiency, fuel, weeding success, and low plant damage. The advantages of the multi-row power weeder were the parameters of theoretical working capacity, effective working capacity, and muddling index.
The Quality of Arabica Coffee Beans Evaluation at Various Processing in Luwu Regency South Sulawesi, Indonesia
Authors: Wibowo Nendyo Adhi , Djufry Fadjry , Syafaruddin  , Iflah Tajul , Dani
Published: June 2022

Arabica coffee plantations in Luwu Regency are planted at elevations above 1,000 mdpl, so that the Arabica coffee clones planted can produce high-quality coffee flavors. The aims of this study were to determine the physical, chemical, and taste profile of Arabica coffee Luwu in order to increase the added value and competitiveness of the product. The research was conducted using a survey method on Arabica coffee plantations in Latimojong District, Luwu Regency, South Sulawesi Province. Sampling using purposive random sampling method and analyzed in duplicate. Samples of coffee variants were obtained from several farmers and from several levels of the coffee trade system around Luwu Regency. Analysis of physical quality characters includes levels of live insects, foul-smelling seeds/mold, moisture content, dirt content, and special quality requirements on seed size, number of seed chips, and defect values. The chemical analysis includes water, ash, caffeine, protein, and fat. The taste of brewed coffee in an organoleptic manner refers to the Specialty Coffee Association of America/SCA standard covering aroma/fragrance, flavor, body, acidity, aftertaste, sweetness, balance, clean cup, uniformity, and overall. Based on the results of the study, the coffee beans met the general quality requirements, there were no live insects, no foul-smelling and/or moldy beans, moisture content of 12.5%, and a maximum dirt content of 0.5%. The value of ash content is 4.344%-5.514%, fat content is 11.194%-14.067%, the highest protein content is 11.687%-13.719%, the highest caffeine content is 0.041%-0.064%. The results of the taste test showed that ten samples had the potential for specialty coffee with a score above 8 and two samples below a score of 8.
Optimized Utilization of Post-Harvest Coffee Agricultural Equipment and Machines
Authors: Setyoningtyas Y D , Darmawati E , Sutrisno
Published: June 2022

Indonesian coffee plantations, which dominate by smallholder plantations with limitary production, technology, and coffee quality, concern the government. One of the Directorate General of Estate Crops interventions to increase market demand is post-harvest equipment and machines for coffee. This study aimed to analyze the combination of available production resources to obtain maximum benefits from assisted machinery. The resource optimization method in this study uses linear programming and is processed using POM-QM software for windows. Respondents in this study were four farmers associations who received assistance in 2017-2020 with the results of their business sustainability studies in the excellent category. The optimal production solution for farmers’ associations is from a combination of products, resources, and sensitivity analysis. The optimization results for green bean farmers association 1, 2, 3, and 4 are 150 kg/month, 300 kg/month, 200 kg/month, and 759 kg/month. As for ground coffee, it is 81.3 kg/month, 83.8 kg/month, 143.3 kg/month and 272 kg/month. With this optimum level of production, it provides a profit of IDR 4,750,000 per month, IDR 2,456,250 per month, IDR 6,333,334 per month, and IDR 9,235,000 per month for farmers association 1, 2, 3, and 4 current levels of production.
Computer-aided patterning of PCL microspheres to build modular scaffolds featuring improved strength and neovascularized tissue integration
Authors: Salerno Aurelio , Palladino Antonio , Pizzoleo Carmela , Attanasio Chiara , Netti Paolo Antonio
Published: June 2022

In the past decade, modular scaffolds prepared by assembling biocompatible and biodegradable building blocks (e.g. microspheres) have found promising applications in tissue engineering (TE) towards the repair/regeneration of damaged and impaired tissues. Nevertheless, to date this approach has failed to be transferred to the clinic due to technological limitations regarding microspheres patterning, a crucial issue for the control of scaffold strength, vascularization and integration in vivo. In this work, we propose a robust and reliable approach to address this issue through the fabrication of polycaprolactone (PCL) microsphere-based scaffolds with in-silico designed microarchitectures and high compression moduli. The scaffold fabrication technique consists of four main steps, starting with the manufacture of uniform PCL microspheres by fluidic emulsion technique. In the second step, patterned polydimethylsiloxane (PDMS) moulds were prepared by soft lithography. Then, layers of 500 µm PCL microspheres with geometrically inspired patterns were obtained by casting the microspheres onto PDMS moulds followed by their thermal sintering. Finally, three-dimensional porous scaffolds were built by the alignment, stacking and sintering of multiple (up to six) layers. The so prepared scaffolds showed excellent morphological and microstructural fidelity with respect to the in-silico models, and mechanical compression properties suitable for load bearing TE applications. Designed porosity and pore size features enabled in vitro human endothelial cells adhesion and growth as well as tissue integration and blood vessels invasion in vivo. Our results highlighted the strong impact of spatial patterning of microspheres on modular scaffolds response, and pay the way about the possibility to fabricate in silico-designed structures featuring biomimetic composition and architectures for specific TE purposes.
Effects of fiber content and its chemical treatment on the mechanical properties of screw pine fiber reinforced vinyl ester composite
Authors: Venkatarajan S , Subbu C , Athijayamani A , Sivagami S M
Published: June 2022

Natural fiber-reinforced polymer composites have several advantages over traditional composites. The chemical modification of natural fibers helps to develop polymer composites with better mechanical properties. In the present work, mechanical properties such as tensile, flexural, and impact strength of chopped Screw pine fiber reinforced vinyl ester composites have been evaluated under-treated conditions based on the volume fractions of Screw pine fibers. The fibers have been treated with 5% of NaOH solution for 1 h at room temperature. The hand lay-up method has been used to prepare composite plates at room temperature. The results revealed that mechanical properties of composites increased with the increase of the fiber content up to 35.57 vol% at both the untreated and treated conditions and then dropped. However, the modulus values have been increased continuously from the fiber content of 8.43 to 45.3 vol%. It was identified that the critical or optimum fiber content for better mechanical properties is 35.57 vol% for both the untreated and treated conditions. The percentage of improvement at every combination was obtained by comparing the composites prepared with the untreated and treated fibers. The fractured surface of the treated fiber composites was examined by scanning electron microscopy. Moreover, the tensile properties are predicted using the Hirsch and Modified Bowyer and Bader model and compared with experimental values. The predicted results revealed that the Modified Bowyer and Bader model shows better conformity.
Discharge and jet characteristics of gliding arc plasma igniter driven by pressure difference
Authors: CHENG Xinyao , SONG Huimin , HUANG Shengfang , ZHU Yifei , ZHANG Zhibo , LI Zhenyang , JIA Min
Published: June 2022

Stable combustion in an afterburner can help increase the thrust of the engine in a short time, thereby improving the maneuverability of a fighter. To improve the ignition performance of an afterburner, a twin-duct ignition platform was designed to study the performance of a gliding arc plasma igniter in close-to-real afterburner conditions. The research was carried out by a combination of experiments and simulations. The working environment of the igniter was explored through a numerical simulation. The results showed that the airflow ejected from the radiating holes formed a swirling sheath, which increased the anti-interference ability of the airflow jet. The influence of the pressure difference between the inlet and outlet of the igniter (Δp), the flow rate outside the igniter outlet (W
2), and the installation angle (α) on the single-cycle discharge energy (E) as well as the maximum arc length (L) were studied through experiments. Three stages were identified: the airflow breakdown stage, the arc evolution stage, and the arc fracture stage. E and L increased by 107.3% and 366.2%, respectively, with Δp increasing from 10 to 70 Torr. The relationship between L and Δp obtained by data fitting is L = 3 − 2.47/(1 + (Δp/25)4). The relationship of L at different α is L

α=0° > (L

α=45° and L

α=135°) > L

α=180° > L

α=90°. E and L decrease by 18.2% and 37.3%, respectively, when Δp = 45 Torr and W
2 is increased from 0 to 250 l min−1.
Research on small flow detection method based on constant power method
Authors: Qin Hongwei , Dang Ruirong , Dang Bo
Published: June 2022

In the field of three phase flow testing, real-time and online wellhead production detection has become an indispensable trend for evaluating well production and well condition. At present, the production of most conventional oil fields in China is low, and there are many Wells with less than 10 m3 d−1. It is difficult to detect the flow of low-flow Wells with conventional metering methods. Therefore, this paper proposes to use thermal flowmeter temperature difference method to measure the flow value. First, COMSOL Multiphysics software was used to build the model of the thermal flow meter and set the size of the temperature probe, heating probe and velocity probe. Secondly, relevant parameters are set to simulate two steady state forms with different water content and different flow rate. Finally, the temperature changes of the velocity probe are simulated under the two conditions. The simulation results show that when the water content is the same and the flow velocity is between 0.0059 m s−1 and 0.059 m s−1, the temperature of the probe decreases with the flow velocity increasing, and the temperature of the probe increases with the flow velocity decreasing. At the same flow rate and water content between 0% and 100%, the higher the water content, the lower the temperature of the speed-measuring probe, and the smaller the water content, the higher the temperature of the speed-measuring probe. The simulation results show that thermal flowmeter can be competent for flow detection of low production fluid and low flow well, which provides the basis for the detection method of low production fluid in the future and lays the foundation for the design of thermal flowmeter.
Differential tolerance to heat stress of young leaves compared to mature leaves of whole plants relate to differential transcriptomes involved in metabolic adaptations to stress
Authors: Xiang Qingyuan , Rathinasabapathi Bala
Published: June 2022

Plants respond to heat shock by regulating gene expression. While transcriptomic changes in response to heat stress are well studied, it is not known whether young and old leaves reprogram transcription differently upon stress. When whole plants of Arabidopsis thaliana were subjected to heat shock, young leaves were affected significantly less than older leaves based on measurements of tissue damage. To identify quantitative changes to transcriptomes between young and old leaves upon heat stress, we used RNA sequencing on young and old leaves from plants exposed to control and heat stress at 42 °C for 1 h and 10 h. A total of 6472 differentially expressed genes between young and old leaf were identified under control condition, and 9126 and 6891 under 1 h and 10 h heat stress, respectively. Analyses of differentially expressed transcripts led to the identification of multiple functional clusters of genes that may have potential roles in the increased heat tolerance of young leaves including higher level of expression in young leaves of genes encoding chaperones, heat shock proteins and proteins known in oxidative stress resistance. Differential levels of transcripts for genes implicated in pectin metabolism, cutin and wax biosynthesis, pentose and glucuronate interconversions, cellulose degradation, indole glucosinolate metabolism and RNA splicing between young and old leaves under heat stress suggest that cell wall remodelling, cuticular wax synthesis and carbohydrate modifications impacted by alternative splicing may also have roles in the improved heat stress tolerance of young leaves.
A Machine Learning Approach to Volatility Forecasting
Authors: Christensen Kim , Siggaard Mathias , Veliyev Bezirgen
Published: June 2022

We inspect how accurate machine learning (ML) is at forecasting realized variance of the Dow Jones Industrial Average index constituents. We compare several ML algorithms, including regularization, regression trees, and neural networks, to multiple heterogeneous autoregressive (HAR) models. ML is implemented with minimal hyperparameter tuning. In spite of this, ML is competitive and beats the HAR lineage, even when the only predictors are the daily, weekly, and monthly lags of realized variance. The forecast gains are more pronounced at longer horizons. We attribute this to higher persistence in the ML models, which helps to approximate the long memory of realized variance. ML also excels at locating incremental information about future volatility from additional predictors. Lastly, we propose an ML measure of variable importance based on accumulated local effects. This shows that while there is agreement about the most important predictors, there is disagreement on their ranking, helping to reconcile our results.
Now is it time to implement spacers in cervical cancer brachytherapy?
Authors: Murakami Naoya , Okuma Kae , Kato Tomoyasu , Igaki Hiroshi
Published: June 2022

Although the international study on MRI-guided brachytherapy in cervical cancer (EMBRACE-I) demonstrated excellent local control regardless of the T stage, up to 14.6% of grade 3–5 late radiation-related toxicities were observed, which is unacceptable. While the efficacy of hydrogel spacers has been established in prostate radiotherapy, its implementation speed in cervical cancer brachytherapy is relatively slow, despite the fact that several articles have reported its efficacy in cervical cancer brachytherapy. The authors believe that using a spacer in cervical cancer brachytherapy and brachytherapy for other gynecologic malignancies will reduce late radiation-related toxicity and improve patients’ quality of life; therefore, its rapid implementation is required.
Unraveling host–microbe interactions and ecosystem functions in moss–bacteria symbioses
Authors: Alvarenga Danillo O , Rousk Kathrin
Published: June 2022

Mosses are non-vascular plants usually found in moist and shaded areas, with great ecological importance in several ecosystems. This is especially true in northern latitudes, where mosses are responsible for up to 100% of primary production in some ecosystems. Mosses establish symbiotic associations with unique bacteria that play key roles in the carbon and nitrogen cycles. For instance, in boreal environments, more than 35% of the nitrogen fixed by diazotrophic symbionts in peatlands is transferred to mosses, directly affecting carbon fixation by the hosts, while moss-associated methanotrophic bacteria contribute 10–30% of moss carbon. Further, half of ecosystem N input may derive from moss–cyanobacteria associations in pristine ecosystems. Moss–bacteria interactions have consequences on a global scale since northern environments sequester 20% of all the carbon generated by forests in the world and stock at least 32% of global terrestrial carbon. Different moss hosts influence bacteria in distinct ways, which suggests that threats to mosses also threaten unique microbial communities with important ecological and biogeochemical consequences. Since their origin ~500 Ma, mosses have interacted with bacteria, making these associations ideal models for understanding the evolution of plant–microbe associations and their contribution to biogeochemical cycles.
Suicide Behavior Results From the U.S. Army’s Suicide Prevention Leadership Tool Study: The Behavioral Health Readiness and Suicide Risk Reduction Review (R4)
Authors: Curley Ltc Justin M , Duffy Farifteh F , Kim Paul Y , Clarke-Walper Kristina M , Riviere Lyndon A , Wilk Joshua E
Published: June 2022

Introduction

The U.S. Army developed a new tool called the Behavioral Health Readiness and Suicide Risk Reduction Review (R4) for suicide prevention. A 12-month evaluation study with the primary objective of testing the hypothesis (H1) that Army units receiving R4 would demonstrate improved outcomes in suicidal-behavior measures following the intervention, relative to control, was then conducted. The results of analyses to answer H1 are herein presented.

Materials and Methods

The R4 intervention (R4-tools/instructions/orientation) evaluation study, Institutional Review Board approved and conducted in May 2019-June 2020, drew samples from two U.S. Army divisions and employed a repeated measurement in pre-/post-quasi-experimental design, including a nonequivalent, but comparable, business-as-usual control. Intervention effectiveness was evaluated using self-report responses to suicide-related measures (Suicide Behaviors Questionnaire—Revised/total-suicide behaviors/ideations/plans/attempts/non-suicidal self-injuries) at 6-/12-month intervals. Analyses examined baseline to follow-up linked and cross-sectional cohorts, incidence/prevalence, and intervention higher-/lower-use R4 subanalyses.

Results

Both divisions demonstrated favorable in-study reductions in total-suicide burden, with relatively equivalent trends for total-suicide behaviors, total-suicide risk (Suicide Behaviors Questionnaire—Revised), suicidal ideations, and non-suicidal self-injuries. Although both demonstrated reductions in suicide plans, the control showed a more robust trend. Neither division demonstrated a significant reduction in suicide attempts, but subgroup analyses showed a significant reduction in pre-coronavirus disease 2019-attempt incidence among those with higher-use R4 relative to control.

Conclusions

There is no evidence of harm associated with the R4 intervention. R4 effectiveness as a function of R4 itself requires confirmatory study. R4 is judged an improvement (no evidence of harm + weak evidence of effectiveness) over the status quo (no safety data or effectiveness studies) with regard to tool-based decision-making support for suicide prevention in the U.S. Army.
Molecular alterations associated with improved outcome in patients with glioblastoma treated with Tumor-Treating Fields
Authors: Pandey Manjari , Xiu Joanne , Mittal Sandeep , Zeng Jia , Saul Michelle , Kesari Santosh , Azadi Amir , Newton Herbert , Deniz Karina , Ladner Katherine , Sumrall Ashley , Korn W Michael , Lou Emil
Published: June 2022

Background

The genomic and overall biologic landscape of glioblastoma (GB) has become clearer over the past 2 decades, as predictive and prognostic biomarkers of both de novo and transformed forms of GB have been identified. The oral chemotherapeutic agent temozolomide (TMZ) has been integral to standard-of-care treatment for nearly 2 decades. More recently, the use of non-pharmacologic interventions, such as application of alternating electric fields, called Tumor-Treating Fields (TTFields), has emerged as a complementary treatment option that increases overall survival (OS) in patients with newly diagnosed GB. The genomic factors associated with improved or lack of response to TTFields are unknown.

Methods

We performed comprehensive genomic analysis of GB tumors resected from 55 patients who went on to receive treatment using TTFields, and compared results to 57 patients who received standard treatment without TTFields.

Results

We found that molecular driver alterations in NF1, and wild-type PIK3CA and epidermal growth factor receptor (EGFR), were associated with increased benefit from TTFields as measured by progression-free survival (PFS) and OS. There were no differences when stratified by TP53 status. When NF1, PIK3CA, and EGFR status were combined as a Molecular Survival Score, the combination of the 3 factors significantly correlated with improved OS and PFS in TTFields-treated patients compared to patients not treated with TTFields.

Conclusions

These results shed light on potential driver and passenger mutations in GB that can be validated as predictive biomarkers of response to TTFields treatment, and provide an objective and testable genomic-based approach to assessing response.