bluuebunny/crossref_metadata_2025 huggingface dataset:
Development of a model for evaluating propagation loss of metal-coated dielectric terahertz waveguides
Authors: Huang Yuyuan , Konishi Kuniaki , Deura Momoko , Shimoyama Yusuke , Yumoto Junji , Kuwata-Gonokami Makoto , Shimogaki Yukihiro , Momose Takeshi
Published: August 2021

A simple physical model for evaluating propagation loss of a metal-coated dielectric terahertz (THz) waveguide with different metal film thicknesses was developed for those fabricated by three-dimensional printing and film coating techniques. Our model enables a comprehensive understanding of the propagation loss mechanism and two key values: the critical film thickness to behave like the bulk material and loss in a sufficiently thick film. To develop the model, in addition to reflection at the metal–dielectric interface, the thickness-dependent electrical conductivity of the metal film was considered. The model was validated by an in-house multi-channel Au-coated THz parallel-plate waveguide in the lowest transverse-electric mode. The estimated critical thickness of our Au film was 171–207 nm at 0.72–1.4 THz. Our model clarified the contribution of three loss components to the overall loss: penetration loss, ohmic loss by bulk conductivity, and ohmic loss by a decrease in conductivity due to thin-film effects. Evaluation of loss over a broader frequency range (0.03–3.0 THz), which corresponds to fifth- to sixth-generation mobile network, revealed that the critical thickness decreased by up to 1.0 THz but increased above this range due to the transition of the dominant loss component from penetration loss to ohmic loss by a decrease in conductivity. As all three loss components and the critical thickness depend on film quality, a deposition process to yield high-quality films is necessary for high-performance waveguides. Our model is applicable to various waveguides, including rectangular waveguides, at any frequency and with any metal film.
Flow-assisted self-healing of the helical structure in a cholesteric liquid crystal
Authors: Eichler Jan-Christoph , Skutnik Robert A. , Mazza Marco G. , Schoen Martin
Published: August 2021

We employ nonequilibrium molecular dynamics simulations to investigate the structure and dynamics of a cholesteric liquid crystal confined between atomically corrugated solid walls. By choosing walls normal to the helical axis, we can study systems with an arbitrary cholesteric pitch without exposing the cholesteric helix to a spurious stress. We investigate the effects of local heating and flow and their joint effects. A steady-state laminar Poiseuille flow is initiated by means of an external body force. Flow alone (i.e., without local heating) in a direction normal to the helical axis does not affect the cholesteric pitch. If the liquid crystal is heated in a small region, the cholesteric helix becomes unstable and melts locally. However, if local heating and flow are combined, a nontrivial synergistic effect is observed in that the helical structure recuperates the better, the higher the speed of the flow is.
Nonlinear density response from imaginary-time correlation functions: Ab initio path integral Monte Carlo simulations of the warm dense electron gas
Authors: Dornheim Tobias , Moldabekov Zhandos A. , Vorberger Jan
Published: August 2021

The ab initio path integral Monte Carlo (PIMC) approach is one of the most successful methods in quantum many-body theory. A particular strength of this method is its straightforward access to imaginary-time correlation functions (ITCFs). For example, the well-known density–density ITCF F(q, τ) allows one to estimate the linear response of a given system for all wave vectors q from a single simulation of the unperturbed system. Moreover, it constitutes the basis for the reconstruction of the dynamic structure factor S(q, ω)—a key quantity in state-of-the-art scattering experiments. In this work, we present analogous relations between the nonlinear density response in the quadratic and cubic order of the perturbation strength and generalized ITCFs measuring correlations between up to four imaginary-time arguments. As a practical demonstration of our new approach, we carry out simulations of the warm dense electron gas and find excellent agreement with previous PIMC results that had been obtained with substantially larger computational effort. In addition, we give a relation between a cubic ITCF and the triple dynamic structure factor S(q1, ω1; q2, ω2), which evokes the enticing possibility to study dynamic three-body effects on an ab initio level.
Proteolytic processing of secretory pathway kinase Fam20C by site-1 protease promotes biomineralization
Authors: Chen Xinxin , Zhang Jianchao , Liu Pulan , Wei Yangyang , Wang Xi’e , Xiao Junyu , Wang Chih-chen , Wang Lei
Published: August 2021

Significance

Fam20C is the bona fide “Golgi casein kinase” and generates the majority of the secreted phosphoproteome. Loss-of-function
FAM20C
mutations cause a type of lethal osteosclerotic bone dysplasia called Raine syndrome. In this study, we find that Fam20C resides in the Golgi apparatus as a transmembrane protein. Site-1 protease, a key regulator of cholesterol homeostasis, cleaves the Fam20C propeptide and promotes its secretion and activation. This proteolytic processing of Fam20C is critical for osteoblast differentiation and mineralization. Our results have important implications for both secretory pathway kinase regulation and biomineralization regulation.
High-throughput suppressor screen demonstrates that RcsF monitors outer membrane integrity and not Bam complex function
Authors: Tata Muralidhar , Kumar Santosh , Lach Sarah R. , Saha Shreya , Hart Elizabeth M. , Konovalova Anna
Published: August 2021

Significance

The bacterial cell envelope is the frontline defense against host immune factors and antibiotics. The regulator of capsule synthesis (Rcs) is a complex signaling pathway that maintains the homeostasis of this essential organelle. Several hypotheses for how the sensory component RcsF activates signaling in response to stress were proposed but could not be directly tested because RcsF proper assembly into the complex with outer membrane proteins (OMPs) depends on the essential β-barrel assembly machine (Bam). We used an extensive genetic analysis to tease apart which RcsF interactions are important for the sensing function. We show that RcsF does not monitor the Bam complex function. Instead, the Bam complex is required to assemble the sensory RcsF/OMP complex that monitors membrane integrity.
Methane-derived carbon flows into host–virus networks at different trophic levels in soil
Authors: Lee Sungeun , Sieradzki Ella T. , Nicolas Alexa M. , Walker Robin L. , Firestone Mary K. , Hazard Christina , Nicol Graeme W.
Published: August 2021

Significance

The impact of soil viruses on prokaryotic hosts and their functional processes is largely unknown. While metagenomic sequencing of soil microbial communities enables identification of linkages between viruses and hosts, this does not necessarily identify contemporary interactions. To enable a detailed analysis of active virus–host interactions between individual populations, we focused on the critical biogeochemical process of methane (CH4) oxidation and followed the transfer of carbon from hosts to their associated viruses in situ. Analysis of13C-enriched metagenomic DNA demonstrated that CH4-derived carbon is transferred into viral biomass via both primary and secondary utilizers of CH4and suggests viral predation is an important mechanism for releasing CH4-derived organic carbon into the soil matrix.
Trends in Binge Drinking, Marijuana Use, Illicit Drug Use, and Polysubstance use by Sexual Identity in the United States (2006–2017)
Authors: McCabe Sean Esteban , Engstrom Curtiss W. , Kcomt Luisa , Evans-Polce Rebecca , West Brady T.
Published: August 2021

Background: National studies often examine associations between sexual identity and substance use at a single point in time and neglect to examine whether these associations change over time. The present study examines U.S. trends in the past-year prevalence of binge drinking, marijuana use, illicit drug use, and polysubstance use across sexual identity subgroups (gay, lesbian, bisexual and heterosexual). Methods: The data come from four independent, cross-sectional samples measured by the National Survey of Family Growth (2006–2010, 2011–2013, 2013–2015, and 2015–2017). Based on the consistency in the sampling procedures used over time, merging the four data sets was possible. The target population is men and women 15–44 years of age. Results: Lesbian women had the sharpest decline in past-year binge drinking over time, followed by heterosexual women. The prevalence of binge drinking for bisexual women did not change significantly over time and was higher in 2015–2017 than for any sexual identity subgroup. In contrast, there were no significant differences in the prevalence of binge drinking among men by sexual identity subgroup. Past-year abstinence from substance use was consistently lower among lesbian women, gay men, and bisexual women relative to other sexual identity subgroups. Polysubstance use was consistently more prevalent among bisexual women (e.g., 32.3% in 2015–2017) as compared to other sexual identity subgroups. Conclusion: This is the first study to examine U.S. national trends in alcohol, marijuana, illicit drug, and polysubstance use across sexual identity subgroups, and demonstrates that sexual identity subgroup differences were robust with relatively few changes in trends over time. The consistently high rates of binge drinking and polysubstance use among bisexual women deserve much closer attention based on the related health consequences.
Inflection reflection: images in mirrors whose curvature changes sign
Authors: Berry M V
Published: August 2021

Mirrors that are convex in some places and concave in others can generate images of extended objects (such as the viewer’s face) that are curiously distorted and often topologically disrupted. Understanding these images involves the caustics of the family of rays emitted by each point of the object, and the totality of all such families constituting the rays from all points of the object. The general theory is illustrated by the simplest mirror with an inflection, whose profile is a cubic function. Simulations, and observations with a flexible plastic mirror, show how the image changes as the viewer moves relative to the mirror.
Radiation induced acceleration of ions in a laser irradiated transparent foil
Authors: Gelfer E G , Fedotov A M , Weber S
Published: August 2021

Radiation friction can have a substantial impact on electron dynamics in a transparent target exposed to a strong laser pulse. In particular, by modifying quiver electron motion, it can strongly enhance the longitudinal charge separation field, thus inducing ion acceleration. We present a model and simulation results for such a radiation induced ion acceleration regime and study the scalings of the maximal attainable and average ion energies with respect to the laser and target parameters. We also compare the performance of this mechanism to the conventional ones.
Symmetry breaking driving spontaneous plasma rotation in tokamak fusion devices
Authors: Li Hanhui , Sun Youwen , Wang Lu , He Kaiyang , Shaing Ker-Chung
Published: August 2021

Plasma rotation plays a critical role in improving plasma confinement in a magnetically confined fusion device. Spontaneous plasma rotation and its reversal of orientation without external momentum input have been observed in some tokamak fusion devices, while the underlying physics is not well understood. A new mechanism based on neoclassical toroidal plasma viscosity induced by symmetry breaking is proposed and well reproduces both spontaneous toroidal rotation and its reversals in tokamaks by considering a small non-axisymmetric displacement in the plasma center, since internal instabilities are often observed in those experiments. The nonlinear hysteresis process of plasma rotation reversals is also well reproduced in the modeling. The mechanism for driving spontaneous plasma rotation proposed in this paper may be utilized for achieving more economical operation of future tokamak fusion reactors.
Development of online learning media based on Telegram Chatbot (Case studies: Programming courses)
Authors: Ardimansyah M I , Widianto M H
Published: August 2021

The Covid-19 pandemic has affected various aspects of life, one of which is education. In some certain areas, at this time the government has issued an interim policy that education provider institutions such as college, schools and its kind to conduct learning activities from home. The existence of this policy makes a change in learning patterns that are usually face-to-face to being forced to apply distance learning methods (online learnings). The limited internet quota, space and time during online learning, as well as different levels of understanding of each student make teaching methods with question and answer also hampered. The solution to that problem, we propose online learning media using Telegram Chatbot. The purpose of this research is to make the Telegram Chatbot as an online learning media with case studies of programming courses, so that be expected students can get learning with the way questions and answers about programming that can be accessed anytime and anywhere, without having to always tied to the educator. The Telegram Chatbot development method using the Prototype Method which is divided into three main stages, which are (1) system requirements analysis, (2) system design and development, and (3) evaluation. The result of our propose development can be an alternative as media learning.
Usability testing of digital map application using hand gesture recognition as a historical learning media for elementary school
Authors: Padmasari A C , Hernawan A H , Rostika D , Wahyuningsih Y
Published: August 2021

The need for digital learning media is currently starting to increase, the use of conventional learning media has become less attractive to students of the current generation. Especially now, the need for digital learning media is starting to increase because the current generation of elementary school students is a generation that easily adapts to technology. Researchers have designed a digital map with a hand gesture recognition as a navigation control instead of a keyboard and mouse. After the application is made, the next step is validating user experience (UX) in the form of usability testing to see user responses. The questionnaire was distributed consisting of 13 questions which were grouped into 4 usability variables. This study involved 50 respondents of grade 4 elementary school students in 5 schools in the Cibiru hilir Bandung and using a linkert scale and get 4 usability variables with a percentage overall feasibility trial from elementary student are 79,25 % and 72,5 % from college student UPI Cibiru. Usability testing media consisting of learnability 80.5% with very good category, system performance is 75, 2% with good category, memorability is 80, 5%, with very good category, satisfaction is 83.3% with very good category.
The development of interactive learning multimedia in teaching mathematics (integer number) to junior high school students
Authors: Imania K A N , Purwanti Y , Bariah S H , Nasrulloh I , Nurazizah N
Published: August 2021

This study aims to create an Interactive Learning Multimedia Product Development. This development research aims to facilitate student learning activities that are in accordance with learning principles and are goal-oriented to be achieved in the learning. This interactive learning multimedia aims to be accessible by students in a more flexible manner without limited space and time, more effectively and it is also hoped that it can be more efficient in its implementation. The research method used is R & D, this development method uses the learning development model proposed by Borg and Gall, Dick & Carrey and J. Moonen. This is done because what will be developed in this research is an interctive learning multimedia development product. The stages in developing interactive learning multimedia designs include 5 stages, namely: (1) preliminary research, (2) initial product development, (3) expert validation and revision, (4) small-scale field trials and product revisions, (5) testing large-scale field and final products.
Synchronous or asynchronous? Various online learning platforms studied in Indonesia 2015-2020
Authors: Setiadi P M , Alia D , Sumardi S , Respati R , Nur L
Published: August 2021

Online learning occupies an important position as an indicator of improving the quality of learning in Indonesia. This paper aims to identify the online learning platform studied in Indonesia in 2015-2020. This is to determine the potential for developing the quality of online learning in Indonesia. There are 178 articles studied in this paper as research population using systematic literature review method. Systematic literature review method is used to list, filter, classify, and identify learning approaches that used in each learning platform. This study used secondary data from the IOP database, especially for articles conducted in Indonesia in 2015-2020. It was found that asynchronous online learning is more widely used about 68 articles. Meanwhile, there are 57 research conducted without specific learning approach. Also, the number of research on online learning conducted in Indonesia is increased by 178 articles in total during 2015-2020. The most widely studied platforms in Indonesia were Edmodo, Moodle, MOOC, and Google Classroom. However, there are tendencies that social media which are not learning platform are treated like learning platforms. This has implications for educators’ to apply online learning using various forms of media and platforms, so that it is starting to be widely accepted.
The instrument for measuring logical-mathematical intelligence of low-grade elementary school students
Authors: Muqodas I , Yuliyanto A
Published: August 2021

The limited measurement of students’ multiple intelligence, especially students’ logical-mathematical intelligence, is the main reason for this research. The purpose of this study is to produce instruments to measure the logical-mathematical intelligence of low-grade elementary school students. Research and Development are used in this research. The study population was all students in Purwakarta. The sampling technique was purposive sampling. The sample was 27 students of the second-grade elementary school in Purwakarta. Validity testing produces nine indicators that are represented by five activity items that are observed through an observation sheet having high validity. The reliability test results through the Cronbach’s Alpha calculation produce a stable instrument with a value of 0.81 > 0.60 for all items. Thus, logical-mathematical intelligence instruments can be utilized in learning in low-grade elementary schools.
The influence of Lectora inspire-based interactive learning media on students’ learning motivation and mathematical reasoning abilities in primary schools
Authors: Suryaningrat E F , Muslihah N N , Pujiasti D A , Adiredja R K
Published: August 2021

The purpose of this study was to find out how much learning Interactive based on lectora inspire influence on the learning process. This research uses collaborative action research between lecturers, students, and teachers in 2019 at one of the primary schools in west Java. Data collection techniques through observation, interviews, and tests. the result of the research is to find out how the impact of the use of learning media lectora inspire based interactive on student’s approach is proven to improve ‘learning motivation and mathematical reasoning abilities in primary schools.
Teaching sine wave concept through simulation for elementary school students
Authors: Nugroho P T , Dewi D P , Fuada S , Putri H E , Jannah F R , Zanah F W
Published: August 2021

In the Natural Science subject for elementary school, one learns about the waves topic which is derived material from sound energy. Students have been taught that waves have periods and frequencies, including the theoretical application of its application in real life. However, the teacher requires a high effort to explain it because it is quite complicated with a short teaching duration. With the help of information computer technology such as an EDA-based software tool, elementary school students can more quickly understand the sine wave material. This paper reveals on how to teach a sine wave material for children with the following topics, i.e., 1) fundamental concept; 2) the introduction of the instrumental tool; 3) introduction of the used Simulator, periods and frequencies measurement using Oscilloscope instruments; 4) Measurement example; and 5) Practicum. These topics are packaged in a new course outside formal schools. The Circuit Wizard simulator was chosen as a teaching tool; we hope to make abstract contents (ex. sine waves) more exact for children and serve many benefits to improve the teaching quality. This paper focuses on the output frequency measurement using Frequency Generator (FG) & analog Oscilloscope pair under the Circuit Wizard simulation. This course can be taken by 4th – 6th grade (10 – 12 years old children).
Virtual scuba diving activities for elementary student to enhance their ocean literacy
Authors: Cahyadi F D , Tarigan D J , Sasongko A S , Prakoso K , Widiyanto K
Published: August 2021

This study aims to analyze the potential use of virtual diving media to improve ocean literacy for elementary school students in Indonesia. Online surveys and literature reviews were used to collect data that were then analyzed descriptively based on aspects of marine literacy. Based on the results of trials by students and teachers, it is known that The World’s Ocean from Google Earth is able to display many underwater locations or spots in Indonesia. The results showed that The World’s Ocean-Google Earth is a virtual scuba diving that has the potential to be used by elementary school students with the advantage of being able to display marine biodiversity in Indonesia and incorporating the essential principles of ocean literacy.
Channeling efficiency reduction in high dose neutron irradiated silicon crystals for high energy and high intensity beam collimation and extraction
Authors: Scandale W. , D'Andrea M. , Esposito L.S. , Garattini M. , Guillermain E. , Mirarchi D. , Montesano S. , Natochii A. , Rossi R. , I. Smirnov G. , Zhovkovska V. , Murtas F. , Galluccio F. , Addesa F. , Iacoangeli F. , Islam Z. , Gavrikov Yu.A. , Ivanov Yu.M. , Koznov M.A. , Malkov M.V. , Malyarenko L.G. , Mamunct I.G. , Borg J. , James T.O. , Hall G. , Pesaresi M.
Published: August 2021

The channeling process in bent silicon crystals are used
since '70s to manipulate beams of high energy particles. During the
last decade, several studies and experiments carried out by the UA9
Collaboration at CERN demonstrated the possibility to use bent
crystals for beam collimation, extraction, focusing and splitting in
particle accelerators. These crystals are subject to deterioration
due to the interaction of the particles with the crystal lattice,
degrading the beam steering performance. For this reason, robustness
tests are crucial to estimate their reliability and operational
lifetime. A ∼8% of reduction in channeling efficiency on
crystals irradiated with 2.5·1021/cm2 thermal neutrons
was measured and reported in this manuscript. Extrapolations to
possible operational scenarios in high energy accelerators are also
discussed.
Avoiding biases in binned fits
Authors: Gligorov V.V. , Hageboeck S. , Nanut T. , Sciandra A. , Tou D.Y.
Published: August 2021

Binned maximum likelihood fits are an attractive option when analysing large datasets, but require care when computing likelihoods of continuous PDFs in bins.
For many years the widely used statistical modelling package evaluated probabilities at the bin centre, leading to significant biases for strongly curved probability density functions.
We demonstrate the biases with real-world examples, and introduce a PDF class to that removes these biases.
The physics and computation performance of this new class are discussed.
The costs of diversity: higher prices for more diverse grassland seed mixtures
Authors: Schaub Sergei , Finger Robert , Buchmann Nina , Steiner Vera , Klaus Valentin H
Published: August 2021

Globally, we face a dramatic biodiversity loss in agricultural systems as well as severe ecosystem degradation. In grasslands, higher biodiversity in terms of plant diversity was shown to increase the diversity of higher trophic levels and provide benefits for farmers such as higher and more stable yields. However, we lack a systematic overview of costs for more diverse seed mixtures, which are an essential tool in maintaining and increasing plant diversity in grasslands. We here investigated the prices and characteristics of 262 commercially available seed mixtures from six German or Swiss online shops and quantified the relationships between seed mixture prices and plant diversity. The most frequent seed mixtures contained 1–10 species and were designed for rather intensive grassland management. On the contrary, a smaller set of seed mixtures with particularly high plant diversity (>30 species), usually of native ecotypes, were offered for restoration purposes. More diverse seed mixtures were also more expensive. For example, a seed mixture with 10 or 30 species was on average +63% or +387% more expensive, respectively, than a product containing only one species. The relationship between plant diversity and seed mixture prices per ha was related to other seed mixture characteristics, of which plant provenance (i.e. native ecotypes vs. cultivars) was particularly important for the price. Seed mixtures containing only native ecotypes had considerably higher prices per ha (⩾+75%) than those including cultivars. In conclusion, increasing biodiversity in grasslands can be costly. These costs need to be considered when making recommendations to farmers and other stakeholders. Measures to reduce such costs for maintaining and/or increasing plant diversity could promote establishment of grasslands with higher plant diversity, facilitate the restoration of semi-natural grasslands, and contribute to solving the biodiversity crisis in agroecosystems.
Changes in Chemical and Sensory Characteristics of Gunungkidul’s Lamtoro (Leucaena Leucocephala) Tempeh during Extended Fermentation
Authors: Prameswari HA , Nursiwi A , Zaman MZ , Ishartani D , Sari AM
Published: August 2021

Lamtoro tempeh is a fermented food in Java, made from lamtoro (Leucaena leucocephala) seeds. Its extended fermentation creates a unique flavor and taste that can be used as a seasoning. Therefore, this study aims to investigate the chemical (moisture, ash, soluble protein, and amino acids contents) and sensory characteristics (brownish color, ammonia aroma, umami taste, and overall acceptability) of lamtoro tempeh from Gunungkidul, Yogyakarta, during extended fermentation for up to 120 hours. The chemical and sensory characteristics were analyzed every 12 and 24 hours respectively. From multiple comparison tests, tempeh with the longest fermentation had the strongest sensory characteristics. Other results showed that extended fermentation increased moisture content up to the highest amount of 74.6% (wb) at 96 hours and 3.55% ash content (db) at 60 hours, as well as soluble protein from 3.02% to 22.62% (db) at the end. Moreover, glutamic acid decreased during fermentation and aspartic acid had the highest amount afterwards. Investigating microbial changes in the food’s unique characteristics during this process is required.
Physical and sensory characteristic of cheese whey frozen yogurt with the addition of arrowroot starch (Marantha arundinaceae L.) as stabilizer
Authors: Mubarokah B , Nurhartadi E , Nursiwi A , Utami R , Sanjaya A P , Widowati E , Zaman M Z
Published: August 2021

In this research, the effect of arrowroot starch addition as stabilizer on physical and sensory characteristics of cheese whey frozen yogurt was determined. The variations of arrowroot starch concentration were 0%, 2%, 4%, and 6% (w/w) total solid. The results showed that the addition of arrowroot starch affected the physical characteristics of cheese whey frozen yogurt, which increases the total dissolved solids, viscosity, and overrun, which were at 23.000 to 26.667 °Brix, from 350.366 to 567.400 cP, and from 11.178 to 51.385%, respectively. Also, the addition of arrowroot starch decreased the melting rate from 25.109 g/min to 19.480 g/min.
The Production Performance and Meat Quality of Kampung Unggul Balitbangtan (KUB) Chicken Fed with Food Containing Indigofera Meal
Authors: Nurhayu A , Ishak A B L , Sariubang M , Ella A
Published: August 2021

This study aimed to determine the production performance and meat quality of KUB chicken meat fed with food containing Indigofera meal. In total, 36 female KUB chickens were raised within the period of 4 to 19 weeks in The Agricultural Technology Research and Assessment Installation, Gowa, South Sulawesi. The experimental design was a complete randomized design divided into three treatments with 12 replications. In addition, the given treatments were categorised as R1 (100% commercial feed), R2 (75% commercial feed, 10% Indigofera meal, 5% bran, 9% corn, and 1% red ginger meal), and R3 (50% commercial feed, 15% Indigofera meal, 9% bran, 25% corn, and 1% red ginger meal). The parameters measured were slaughter weight, carcass weight, and nutritional content of meat. The results showed that the treatment of feed significantly affected (P < 0.05) the slaughter weight and carcass weight of KUB chicken. R2 treatment showed the highest slaughter weight and carcass weight compared to other treatments, which are 1069.5 g/head and 701.2 g/head. Furthermore, the meat crude protein and crude fat analysis indicated that R2 treatment had the highest crude protein (30.18%), lowest fat (0.11%), and cholesterol content (47.8 mg/100 g). Conclusively, the addition of 10% Indigofera meal to the feed was able to improve the production performance and meat quality of KUB chicken.
The Use of Chitosan as Non-toxic Flocculant for Harvesting Microalgae Spirulina sp
Authors: Rokhati N , Prasetyaningrum A , Aji R W , Hamada N’A
Published: August 2021

Spirulinais a type of microalgae widely consumed as a food supplement due to its high nutritious benefits. Furthermore, it is very small and lives floating in water, making it quite difficult to harvest. One effective method of harvestingSpirulinais by coagulation/flocculation. In order to successfully harvestSpirulina, choosing the right flocculant material is very important. Chitosan, a natural polymer that has a cationic amine group, is often used in the food industry. This is because colloidal particles (polymer) that exist in nature are mostly negatively charged (including microalgae) and electrostatic interactions between cationic polymers with anionic polymers lead to the formation of flocculants. Therefore, this study was carried out to measure the feasibility of chitosan as a flocculant in the flocculation process of harvesting microalgae. The experiments were carried out with the variation of the concentration of chitosan, pH and slow-stirring speed, using efficiency of flocculation and sedimentation speed as parameters. The result showed that optimum condition was achieved at a slow-stirring speed of 40 rpm, sedimentation time of 2 hours, chitosan concentration of 100 mg/L and pH of 7-8. In this condition, the flocculation efficiency was 99.57%.
The Effect of Vegetable oils (Palm Oil, Canola, Coconut and Soybean Oil) on the Ration of Slaughter Weight, Carcass Weight, Carcass Percentage, and Abdominal fat Percentage of male ducks
Authors: Hadi R F , Sudiyono  , Wati A K
Published: August 2021

This study aims to analyze the effect of different vegetable oils on the basal ration of slaughter and carcass weight, carcass percentage, as well as abdominal fat, percentage in 9 weeks old of male ducks. It was conducted using a Completely Randomized Design (CRD) in an unidirectional pattern with 4 treatments and 6 replications with 6 ducks in each test. The treatments in this study include; P1: (96% basal ration + 4% palm oil); P2: (96% basal ration + 4% canola oil); P3: (96% basal ration + 4% coconut oil) and P4: (96% basal ration + 4% soybean oil). Furthermore, the data were analyzed using the one way analysis of variance (ANOVA), meanwhile Duncan’s multiple range test (DMRT) was applied when significant differences were indicated among treatments. The analysis showed that the treatments have no significant effects (P > 0.05) on the variables examined in this study. Base on the results that the addition of different types of vegetable oil in the basal ration failed to increase slaughter weight, carcass weight, carcass percentage, as well as the abdominal fat percentage in male ducks.
The profit of wet and dry form of porang farming in Madiun Regency, East Java, Indonesia
Authors: Susanawati  , Satyarini T B , Wijayanti P P
Published: August 2021

This study aims to describe the profile of farmers, and the profit of porang farming. A proportional random sampling was used which involved 30 chip-selling farmers and 70 farmers selling wet tubers during a 3-year growing season in 2016-2019. Data analysis was conducted descriptively in tabular form. The results showed that all farmers were male, with the majority classified into the productive age, and a dominant educational level of elementary school. Furthermore, farming experience was below 13 years, with the Indonesian rosewood as the most widely used stand plant specie. Most farmers utilized less than 1.3 ha of Perhutani’s land. Sixty farmers sold the crops in form of wet tubers, 26 sold in form of chips (dry tubers), 6 sold wet tubers and chips (dry tubers), 4 sold bulbil/frogs and wet tubers, and 4 farmers sold the bulbil/frog and chips (dried tubers). The largest expenditure was the cost of seeds, amounting to 45.67% of the total expenditure, although included in the implicit costs. Therefore, farmers’ profit from porang farming reached 14,649,032 IDR for three years.
Evaluation of Organic Liquid Fertilizer Concentration and Planting Media on Growth and Yield of Red Spinach (Amaranthus Tricolor L.) in Hydroponic Axis System
Authors: Nanik L , Muslikan
Published: August 2021

This study aimed to investigate the effect of organic liquid fertilizers (OLF) and different planting media on the growth of red spinach (Amaranthus tricolor L.). It was conducted in Kepuhsari sub-village, Kepuhrejo Village, Kudu district, Jombang regency, East Java between October and November 2019. Furthermore, a completely randomized design with two factors and triplicates observation was carried out. The First factor was the concentration of organic liquid fertilizer (OLF, which includes OLF 0% (K0), OLF 25% (K1), OLF 50% (K2), and OLF 75% (K3). The second factor included planting media such as 100% (M1) husk charcoal, 100% cocopeat (M2), and a mix of 50% of husk charcoal and 50% cocopeat (M3). The variables observed were plant height, number of leaves, area, stem diameter, root weight, wet and dry weight of stems and leaves. These parameters were analyzed by ANOVA and BNT test at a confidence level of 5%. The results showed that OLF 50% (K2) significantly influenced the growth of red spinach plants. Also, a mixture of 50% husk charcoal and cocopeat (M3) planting media induced a very significant effect on various observational variables.
Effectiveness of fermentation extract of cabbage leaves from harvesting waste to control purple blotch of garlic
Authors: Supyani  , Hadiwiyono  , Poromarto S H , Widono S , Septariani D N , Putri C P
Published: August 2021

Purple blotch caused by Alternaría porri, has an impact on garlic plantings. Furthermore, the severity of this disease on local garlic varieties can be greater than 60 %. This led to the use of a biological control, involving agricultural waste biomass of cabbage leaves as a form of alternative control against this disease. Also, these biological waste biomasses were chosen because their fermentation process produces antimicrobial compounds, which inhibits pathogen growth. This research aimed to analyse the effectiveness of fermentation extract of cabbage leaves, in order to control purple blotch on garlic, the level of concentration needed, and the frequency of the most effective applications. Furthermore, it used a completely randomized design for in vitro testing, and the non-factorial randomized complete block model for in vivo analysis, which involved 8 treatments. The results showed that the fermentation extract with a concentration of 200 mL.L−1, effectively inhibited 100% of colony growth, while the bi-weekly application of this product at 300 mL.L−1, effectively suppressed the disease incidence of purple blotch, by up to 74.69 %.
Changes in the quality of some improved rice grain varieties during storage
Authors: Jumali  , Kusbiantoro B , Handoko D D
Published: August 2021

This research aimed to investigate the changes in the quality of some improved rice grain varieties during storage. In the rainy season of 2014/2015, 10 improved rice varieties, namely, Inpari 10, 13, 16, 20, 30, Sintanur, Ciherang, Mekongga, Situ Bagendit, and Situ Patenggang, were planted at the Sukamandi Research Station, Indonesian Center for Rice Research. The rough rice grains were harvested at optimum maturity, machine threshed, and dried with a box dryer’s aid at a temperature of 45°C for 10 hours until the water content was at 13-14%. Furthermore, they were packed in plastic sacks and stored at room temperature for six months (March-November 2015). At 0, 3, and 6 months of storage, the rice’s physical, milling, and physicochemical qualities were analyzed. The results showed that the quality of all the rice grain varieties equally decreased during the six months of storage while the average grain moisture content slightly increased by 13.7% (13.30-14.16%). In addition, the yield of unpolished, polished, and head rice slightly decreased. While the percentage of broken rice, groats, green/chalky, and yellowing/damage grains slightly increased. Additionally, the gel consistency and alkali digestion remained constant, while the amylose content, water absorption ratio, and volume expansion ratio slightly increased.
Technical and Fumigation Time Effects on Shallot Storage Quality
Authors: Aini A B N , Karseno
Published: August 2021

Storage involves management after harvest which plays an important role in the quality control of shallots. Shallot farmers also store using the traditional methods of fumigation, e.g smoke, which is used in liquid smoke processing. This research aims to determine the effect of smoking during storage on the physical and sensory characteristics of shallots. The random nature of the block had two factors: smoking (traditional smoking, spraying, dipping methods) and smoking time (1, 2, and 3 hours respectively). The measured variables include weight loss, moisture content, damage and sensory characteristics (texture, flavour). Furthermore, tests were conducted every week for 4 weeks without fumigation according to controls. The results showed that fluid smoke decreases weight loss, moisture content, and lowers the risk of damage using the immersion process. The consistency of shallots can be preserved for up to four weeks by soaking in liquid smoke for 2 hours. There was a weight loss of 4.6%, damage of 1.17% and moisture content of 82.5%. Smokeless shallots also had a weight loss of 33%, damage of 9.17% and humidity 87.29%. Therefore, soaking shallots for 2 hours in liquid smoke helps to retain their physical and chemical properties without changing their sensory characteristics.
Physical, Chemical, Physicochemical, and Sensory Properties of Analog Rice Based on Purple Sweet Potato Flour (Ipomoea batatas L.) and Bambara Groundnut Flour (Vigna subterranea L.)
Authors: Ariyantoro A R , Praseptiangga D , Anam C , Anandito R B K , Yulviatun A , Atmaka W , Fadzil M , Boonsupthip W
Published: August 2021

The aim of this study is to determine the best formulation based on sensory properties and to compare the physical, chemical and physicochemical properties of the analog rice with the analog rice of purple gray and red commercial sweet potatoes. Furthermore, a completely randomized design (CRD) with one factor was used, the Bambara Peanut Meal Difference in formulation 0% (FI); 15% (F2); 30% (F3), 45% (F4); and 60% (F5). 1.5% GMS, 1.5% CMC, 2% palm oil and 25% water were added to each formulation. The data were analyzed statistically by using oneway ANOVA. The significant difference was further tested using Duncan’s new multiple range test (DMRT) at a significance level of α = 0,05. The best sample was selected based on sensory evaluation made from 85% purple sweet potato flour and 15% bambara groundnut flour (F2 analog rice). The F2 analog rice is then compared with red rice and commercial purple sweet potato analog rice based on the physical, chemical and physicochemical properties. The results showed that F2 analog rice has an L 42.41; bulk density 0.57 g/ml; grain weight 0.02 g; moisture 6.55%; ash 4.34%; fat 4.82%; protein 5.77%; carbohydrate content 85.07%; total dietary fiber content 14.96%; water absorption 175.50%; swelling power 8.99 g/g; solubility 23.45%, and cooking time 11.54 minutes. The result has shorter cooking time and higher total dietary fiber content (F2 sample) than commercial analog rice and red rice.
Amylograph properties and microstructure of white corn and okara-based composite flour
Authors: Ishartani D , Sagita R , Praseptiangga D
Published: August 2021

Okara flour is rich in protein and dietary fiber and could be used to enrich white corn flour to enhance its functionality. This research was designed to investigate the amylograph properties and microstructure of a composite flour made from white corn and okara flours. The composite flour was made using five different ratios of white corn flour:okara flour (100%:0%, 95%:5%, 90%:10%, 85%:15%, and 80%:20%). White corn flour and okara flour were mixed manually and prepared in duplicates. Amylograph properties were observed using a Rapid Visco Analyzer (RVA) and microstructure was observed using Scanning Electron Microscopy (SEM). The composite flour had a pasting temperature range of 78.30°C to 79.90°C, peak viscosity of 126cP to 1977cP, trough viscosity of 1016cP to 1596cP, breakdown viscosity of 245cP to 516cP, final viscosity of 2079cP to 3248cP, and a setback viscosity range of 1063cP to 1652cP. Microstructural analysis clearly showed that white corn and okara flour particles did not break. Composite flours based on the white corn and okara mix used in this research could potentially be developed as raw materials for use in food products with characteristics that are not brittle nor easily broken, including analog rice.
Physical Quality of Chevon Meatballs with Different Levels of Taro Flour Substitution as a Filler
Authors: Nuhriawangsa A M P , Budiharjo A , Swastike W , Hertanto B S , Adriyanto B , Kartikasari L R
Published: August 2021

Taro tubers potentially serve as functional foods with significant health benefits, due to their abundant oligosaccharides. The substance is a potential raw material in flour production, as a result of their high starch composition of approximately 70%. The purpose of this research, therefore, was to determine the physical properties of chevon meatballs, comprising of various levels of taro substitutes as fillers. The materials involved were the thighs of the meat sample and taro flour. Additional ingredients consisted of ice, tapioca flour, pepper, salt, MSG, egg white, and garlic. Meatballs were produced from chevon with 10% flour as filler, in the form of tapioca and taro, with successive composition ratio of 10:0 (P0), 7.5:2.5 (P1), 5:5 (P2), 2.5:7.5 (P3), and 0:10 (P4). Data assessments were subsequently conducted, using analysis of variance (ANOVA). The results showed that the use of taro flour filler up to a level 10% did not affect the cooking loss of chevon meatballs, with exception in pH, water holding capacity (WHC) and tenderness. Consequently, the addition of filler ratio of 0:10 (tapioca:taro) tended to boost the pH, while reducing the WHC and tenderness. Moreover, the WHC increased by using tapioca and taro flours with a ratio of 5:5 (P2), compared to 7.5:2.5 (P1), 2.5:7.5 (P3), and 0:10 (P4). Furthermore, a considerable improvement in meatball tenderness was observed by the inclusion of P2 filler ratio, compared to utilizing tapioca and taro flours at 2.5:7.5 (P3) and 0:10 (P4). In summary, taro flour was feasibly applied in chevon meatball preparation up to a level of 5%, while retaining the physical properties.
Nutritional Value of Chicken Meat Fed Diet Supplemented with Purslane Rich in Omega-3 Fats
Authors: Kartikasari L R , Hertanto B S , Nuhriawangsa A M P
Published: August 2021

This study aims to examine the effect of dietary supplementation in the form of purslane meal (Portulaca oleraceae) as a source of omega-3 fats on the nutritional value of broiler chickens. A total of 180 one-day old unsexed Lohmann broiler chickens was randomly allocated into 30 pens, with each one consisting of 6 chickens. Thereafter the pens were randomly assigned to five experimental diets with 3 replicates (36 birds per treatment). The diets were formulated by adding a basal diet to 0, 1.5, 3.0, 4.5 and 6.0% purslane meal. The water and diets were provided ad libitum throughout the experiment. Furthermore, after 35 days, six chickens per treatment group were slaughtered and processed as carcass. Breast meat were collected for chemical analysis of protein, fat, moisture and collagen using FoodScan Near-Infrared Spectrophotometer, while the data were analysed using ANOVA. Moreover, differences among treatment means were further analysed using Tukey’s test. The results showed that diets enriched with omega-3 fats in the form of alpha-linolenic acid had no effect on the collagen content of chicken meat with an average of 1.41%. In addition, the meat protein level which was approximately 22% was the same among dietary treatments. There was also no significant difference in the fat content of meat fed the dietary purslane meal with an average of 2.83%. Based on the results, it was concluded that the nutritional value of broiler chicken meat was not altered by the dietary inclusion level of 6% Portulaca oleracea (purslane) meal as a source of omega-3 fats. Further studies are needed to evaluate whether the supplementation of purslane meal at a higher level is capable of improving the chemical quality of broiler chicken meat.
The Effect of Different Concentrations and Exposure Durations of Ethylene Gas on Peel Colour Change of Citrus (Citrus nobilis) in the De-greening Process
Authors: Fauziah TN , Bintoro N
Published: August 2021

De-greening using ethylene gas is one of the methods to change the peel colour of an in-attractive fruit appearance. Therefore, this research aims to investigate the effect of ethylene concentration and exposure duration on the peel colour changes of Citrus. Ethylene concentrations of 0, 50, 100, and 150 ppm and exposure durations of 24, 48, and 72 h were researched in factorial design 4 x 3 with three replications. Green ripe Citruses were cleaned and selected as the samples which were treated with ethylene gas in a closed box, then removed and stored in the open room until the peel changed uniformly to orange. The colours were measured using a colourimeter (3nh, SC-10) every 12 h for 4 days. It was found that as the storage time passed, the redness value turned from negative to positive, while yellowness increased consistently. Statistical analysis indicated that ethylene concentrations and exposure durations had a significant effect on redness, yellowness, chroma, and hue angle. The largest value of the observed parameter was found at 150 ppm concentration and 72 h exposure duration. This de-greening also altered the Colour Index value from −5.51 to 6.77.