bluuebunny/crossref_metadata_2025 huggingface dataset:
Analisis Statis Konstruksi dan Lance Tube Sootblower Tipe Motorised Rotary Menggunakan Software Solidworks 2016
Authors:   Universitas Negeri Semarang, Felani Ahmad , Al-Janan Dony Hidayat
Published: October 2021

Sootblower is a boiler support equipment that works to clean soot. Sootblower requires a strong construction to support the components in order to work optimally. Sootblower is also not free from several failures on its components, the main component that causes failure on the sootblower is the lance tube. This study aims to analyze the static construction and lance tube motorized rotary sootblower type sootblower using Solidworks software. The method used in this research is a simulation based on the finite element method. The material applied to the construction is St 37 and the material on the lance tube is ASTM A213 T92. The static simulation results show that the construction design of the angle iron measuring 35×35×6 mm has a max stress value of 57,50 N/mm2 that occurs in the bolt hole, a value of max displacement of 0,0146 mm on the rod supporting the bearing, and a factor of safety value of 4,08 so it is safe to use. Static simulation on the design of 40 NB diameter lance tube with four thickness variations shows the highest max stress value, the highest max displacement, and the lowest factor of safety occurs in the lance tube thickness of 10,2 mm, which has a max stress value of 276,24 N/mm2, max displacement of 335,53 mm and a factor of safety 1,59. Lance tubes with a thickness of 10,2 mm can be declared safe because the value of the factor of safety meets the minimum limit for static loading.
Pengaruh Proses Bubut Baja AISI 4140 terhadap Mental Workload dengan Metode NASA-TLX
Authors:   Politeknik Negeri Indramayu, Rahmi Meri , Rachmatulllah Rachmatulllah , Sukardi Casiman ,   Politeknik Manufaktur Negeri Bandung
Published: October 2021

This study aims to analyze the mental workload with the experimental method when operating a lathe under two different conditions, namely by using cooling and without cooling. The material used as the specimen in this research is AISI 4140 material. Another important variable is the timing of the experiment in the morning and evening. This is related to the division of work shifts that often occurs in the manufacturing industry. The working time factor greatly affects work performance and vigilance at work. Based on the experimental results taken from 20 participants and processed with the NASA-TLX method, it shows that the mental workload in the lathe process with the addition of cooling is more significant than the lathe process without the addition of cooling, even though the data collection time is different. It is also directly proportional to the duration of the lathe process. So it can be concluded that the turning process is better to use cooling even on AISI 4140 Steel material because it does not require a high workload.
Performa pada Motor Bakar 6-Langkah dengan Langkah Power Ekspansi sampai Titik Mati Bawah
Authors:   Universitas Brawijaya, Sepriyatno Riswan , Siswanto Eko , Hamidi Nurkholis
Published: October 2021

This study aims are to observe the performance of a six-stroke combustion motor and to analyze the thermodynamics of a six-stroke combustion engine with a power expansion step to the bottom dead center. The fuel used in this observation is pertalite with a RON 90 value. The method used is a true experimental method, with independent variables, namely 35%, 40%, 45%, and 50% throttle openings with loading on the prony disc brake of 10 kg, 20kg, 30kg, 40kg, and 50kg. In the torque data, each throttle opening shows the highest number of 7.26 (Nm) with a load of 50kg and the lowest value of 2.01 (Nm) with a load of 10kg, for effective power the highest value is 8.47 (kW) at 50% throttle opening with load is 40kg and the lowest value is 2.49 (kW) at 35% throttle opening with a load of 10kg, while for the specific fuel consumption (SFC) the highest value is 4.28 (kg/Hp.h) at 40% throttle opening with a load of 10kg and the lowest value is 0.77 (kg/Hp.h) at 50% throttle openings with a load of 50kg, and for the thermal efficiency of the six-stroke motor, which means an average increase of 14.58% compared to the thermal efficiency of the conventional 4-stroke internal combustion engine.
Pengaruh Variasi Bio Based Adhesive terhadap Kekuatan Peeling dan Shearing Kayu Pinus pada Adhesive Joint
Authors:   Universitas Brawijaya, Ma’arif Mochammad Syamsul , Fadlurahman Muhammad , Anam Khairul
Published: October 2021

The methods of joining engineering materials using adhesives is mostly implemented by using synthetic adhesives from non-renewable sources. Even though it has good joining performance, its poisonous nature and difficult to decompose naturally makes the adhesive needs to seek alternatives that are more environmentally friendly. Another reason is to support FAO campaigns for the use of environmentally friendly and biodegradable materials. One that has the potential to replace synthetic one is adhesives from natural sources such as gum rubber, jackfruit, and breadfruit. Because each natural sap has a different composition, the adhesive strength will also be different. Therefore it is necessary to examine the adhesive strength of each of these natural gums. In this research, natural adhesives (gums) and synthetic adhesives were used to joint pine wood as a test specimen. After joining, peeling and shearing tests on the specimens were carried out so that the mechanical strength of the joints for each adhesive variation was recognized. Fracture analysis was then performed to analyze the mechanism of joint failure for each adhesive variation. From this research, the highest peeling strength was obtained from rubber tree sap of 0.15 MPa, while the highest shearing strength was also obtained for rubber sap of 0.68 MPa.
Pengaruh Campuran Bahan Bakar Biodiesel WCO - Diesel terhadap Karakteristik Api Hasil Pembakaran Spray Difusi pada Concentric Jet Burner
Authors:   Universitas Brawijaya, Sukri Sukri , Sasongko Mega Nur , Widodo Teguh Dwi
Published: October 2021

Biofuels from waste cooking oil (WCO) represent a sizable opportunity not only in terms of energy production but also as a way for sustainable development despite their low yield, higher viscosity, lengthy production time and cost. Alternatively, biodiesel can be blended at an appropriate blending ratio with convention diesel oils. The biodiesel and its blends is proved to give better emission characteristics than conventional diesel oils. This study aims to experimentally investigate the effect of the fuel blend on the combustion characteristics of WCO biodiesel. The characteristic are the droplet size, flame height, flame width and temperature distribution. In this study, the blended fuel are B0 (Solar), B10, B20, B30, B40 and B100 (WCO biodiesel). Measurement and visualization of the combustion flame for each variation of the fuel mixture was were tested at different pressures, namely 4 bar and 5 bar. The experimental results show that the droplet size increases with increasing WCO concentration in the fuel; on the other hand, visualization and calculations show that the height and width of the flame of the fuel mixture decreases Observation on the temperature distribution shows that the WCO biodiesel mixture has the potential to increase the fire temperature at certain points
Analisis Ketidaksesumbuan Poros (Misalignment) pada Rotordinamik Berdasarkan Sinyal Suara
Authors:   Universitas Bengkulu, Suryadi Dedi , Febriyanto M Reza , Fitrilina Fitrilina
Published: October 2021

This research aims to identify misalignment of the rotor dynamics based on sound spectrum characteristic. In this study, rotor dynamics consist of motor, shaft, coupling and bearings. Three types of misalignment were considered, namely parallel, angular, and combination misalignment. In order to obtain the best signal, microphones were used as sensors to capture sound signal placed on coupling and each bearing. The signal obtained was in time series. The sound signal in the time domain is then filtered to remove noise signals, which are then transferred to be signals in the frequency domain using Fast Fourier Transform (FFT). From the test results, it is found that in the case of parallel misalignment, the sound frequency spectrum is obtained with a peak amplitude at 2x rpm. The case of angular misalignment obtained a sound spectrum with a peak amplitude value and is dominant at 1x rpm than 2x rpm. Meanwhile, in the case of a combination of parallel and angular misalignment, a peak amplitude sound spectrum appears at 1x rpm and 2x rpm with relatively close spacing between the peaks of the sound spectrum. The result shows that sound signal can be used for identification of misalignment of the rotor dynamics.
Potensi Serbuk Kayu Ulin dan Serbuk Bambu Sebagai Aplikasi Papan Partikel Ramah Lingkungan - Review
Authors:   Institut Teknologi Kalimantan, Laksono Andromeda Dwi , Rozikin Muhammad Nurhidayatur , Pattara Nur Aini Safitri , Cahyadi Ifdil
Published: October 2021

The wood and bamboo waste from the exploitation and industry are still not fully utilized where they are now being used as raw material for particleboard. The purpose of this narrative review is to find out the concept of particleboard, the mechanism of particleboard, and the potential for wood and bamboo powder in particleboard applications. The method of creating particleboard was using dehydrated sawdust and bamboo then pouring the powder with adhesive. In this narrative review, there are several types of adhesives which are Polyurethane Resin, Phenol-Formaldehyde (PF), Epoxy, Polystyrene Based Resin (PBR), and Unsaturated Polyester (UP). After molding powder and adhesive mixture, it was hot-pressed to make a particleboard product. Finally, the mixture was tested for the physical and mechanical properties of particleboard products based on Indonesian National Standard. The physical and mechanical properties are increases by particleboard with a proportion of 75%-100% teak wood (T. Grandis) and 25%-50% bamboo. It's known that ironwood has characteristics close to that of the teak species. Therefore, the ironwood and bamboo sawdust has the potential to be used as raw material for particleboard. And the recommended method based on the type of adhesive used is UP.
Identifikasi Kerusakan Altenator Daihatsu Luxio dengan Metoda Fungsi Respon Frekuensi
Authors:   Universitas Mercu Buana, Subekti Subekti , Hidayat Muhammad Nurul , Hamid Abdul , Efendi Basuki Dwi ,   PT. Astra Daihatsu, Silaen Jeffri ,   Universitas Mercu Buana, Widodo Aditya Putra
Published: October 2021

Gasoline engines should sound soft, even tend to be minimal. But when the symptom of a rough sound emerged from the engine room, it was even more like a diesel sound that was quite loud. So that many customers have complained about the rough sound of their vehicle's engine when the engine is started, from the results of the initial inspection that was carried out as a result of the rough noise coming from the bearings on the alternator which experienced wear due to reduced lubrication in the bearings. This requires that preventive maintenance checks on the alternator are a must in the automotive world. On the basis of the above, in this paper, we will discuss the damage to the Daihatsu Luxio alternator with the frequency response function (FRF) method. Damage to the alternator can be seen at point A and point D, seen with a frequency at 1500 Hz in a damaged condition, while in good condition there is no frequency at 1500 Hz. At points B, C, E, and F have the same vibration pattern between the damaged and undamaged conditions. Visually checking results show that the bearing component at point A, it is known that the ball bearing is peeling. This results in a rough spinning of the bearing and makes the alternator make a rough noise while working.
Pengaruh Massa Filler-Matriks terhadap Sifat Mekanik dan Daya Serap Air pada Komposit Cangkang Biji Karet
Authors:   Institut Teknologi Kalimantan, Ismail Andi Idhil , Rasidah Rasidah , Haliq Ridhwan
Published: October 2021

The amount of rubber seed waste in Indonesia is highly yielded as a side product from a large amount of rubber trees plantation. The rubber seed was not processed become the usefull application yet, thus it becomes a high volume of waste in each year. An initiative should be done to turn it as a practical material. The rubber seed is potential for natural composite along with the increasing attention toward natural composite application.This work aims to produce natural fibre composite based on rubber seed and characterize it's mechanical properties. In this work, the rubber seed natural composite produced by using the hand lay-up method. Polyester resin YUCALAC BQTN-157 was used as the matrix with the addition of 1% MEKP (Methyl-Ethyl-Ketone- Peroxide) as the catalyst. Mechanical properties of the composite were examined by using a tensile and bending test. Additionally, the water absorption test was performed according to the ASTM D 570. The result showed that the tensile and bending strength decrease with increasing the filler composition, which is added in the composite. The composite, which has the filler composition of 40% was generate the highest tensile strength. In contrast, the lowest tensile strength appeared at the composite with a filler of 60%. The bending strength trend also behaves similarly with the tensile strength as the filler composition increased. Water absorption ability of composites displays the acceptable value as it shows within the range of 2.22-2.96%.
Performa Panel Surya 2 X 50 WP pada Mesin Panen Padi Mini Dua Lajur
Authors:   Universitas Teuku Umar, Susanto Herdi , Darsan Herri , Mukhlizar Mukhlizar ,   STAIN Tengku Dirundeng, Fitriadi Nuzuli ,   Politeknik Aceh Selatan
Published: October 2021

Rice harvesting machines that can be operated in swampy, peatland, narrow and can be operated and maintained by farmers, can be considered for design, some previous research has been carried out, including a two-lane mini rice harvester with a performance of 20.33 hours per hectare and has been in manufacturing and in performance tests. Experimental studies on engine performance were carried out in this research. This research uses 2x50 watt peak polycrystalline solar panels connected to a 12 volt 45 AH battery, the battery will drive a 50 watt electric motor. Current and voltage measurements are carried out on the solar panel and battery when in condition, first the solar panel is connected to the battery and not connected to the electric motor, the second solar panel is connected to the battery and connected to the electric motor, the three solar panels are not connected to the battery and the battery is connected to electric motor. The results of the first condition study indicate that the electric current will be more stable using a new battery, when compared to using a battery in the previous study. The second condition was that the performance of the two-lane mini rice harvester increased by 50% when compared to the performance of an electric motor using a battery that was not connected to a solar panel. The third condition shows the performance of the electric motor has increased by up to 300% when compared with the results of previous studies, it is estimated that the electric motor will continue to rotate for up to 8-10 hours.
Studi Karakteristik Stabilitas dan Konstruksi Kapal Berbahan High Density Polyethylene (HDPE)
Authors:   Universitas Brawijaya, Kadhafi Muammar , Sunardi Sunardi , Triono Agus ,   Universitas Jember, Sari Wahida Kartika ,   Universitas Brawijaya
Published: October 2021

The development of fishing and marine tourism requires the support of naval architecture, especially in small boat. The use of wood as the main material for shipbuilding has recently become a problem considering the decreasing availability of wood, while the use of fiber is classified as less environmentally friendly because it uses chemical resin and difficult to repair when it breaks and cannot be recycled. The aim of this research is to design the High-Density Polyethylene (HDPE) boat. The design was carried out by using naval architect design software. The stability of boat was calculated by using three loading conditions such as when leaving the port, in the sea and when returning to the port. The International Maritime Organization (IMO) safety criteria was using to evaluation of boat stability where the three loading conditions have met the IMO standard. The construction of HDPE boat was carried out by using DNV rules.
Dampak Relokasi Terhadap Perubahan Ruang dan Sosial Ekonomi Masyarakat Permukiman Kalijodo di Jakarta
Authors:   Program Studi Arsitektur Universitas Muhammadiyah Jakarta, Sutantio Alfan , Ismawan Guntur , Karim Muhammad Arifandi , Hantono Dedi
Published: October 2021

Kota Jakarta Memiliki kepadatan dan kota yang sangat kompleks sehingga tidak dapat menampung seluruh kegiatan didalamnya dikarenakan semakin berkembangnnya penduduk atas berbagai aktifitas sehingga terjadinya transformasi atas kegiatan di pinggiran kota sehingga terjadinnya alih fungsi lahan yang tidak sesuai dengan ketentuan yang sudah diberlakukan oleh pemerintah Kota DKI Jakarta. Dari hal tersebut munculnnya rumusan masalah mengenai kondisi sebelum dan sesuda dari kawasan Kalijodo, serta dampak sosial ekonomi yang dihasilkan dari relokasi permukiman kawasan terbuka Kalijodo. Metode yang digunakan berupa kualitatif deskriptif Metode tersebut berupa pembahasan opini atau teori yang di gabung dari beberapa teori dengan mengacu dari beberapa jurnal, artikel ilmiah atau bentuk tulisan ilmiah lainnya. Analisis yang digunakan berupa dampak sosial ekonomi relokasi terhadap permukiman warga di kalijodo dengan di tampilkan dalam bentuk tabel serta dari hasil tersebut memiliki kesimpulan bahwa dampak relokasi Kawasan Kalijodo mendapat kehidupan yang mencukupi dan lebih baik dari sebelumnya. Penataan kawasan tersebut berdampak untuk membentuk karakter warga yang lebih bermoral dan sejahtera.
I Encontro Acadêmico de Neurologia, Neurocirurgia e Neurociências
Authors: (UFMG) Universidade Federal de Minas Gerais
Published: October 2021

O I Encontro Acadêmico de Neurologia, Neurocirurgia e Neurociências foi apresentado dos dias 07 a 10 de junho de 2021, de forma totalmente online. O evento foi planejado e executado a partir da parceria de estudantes de Medicina da Faculdade de Medicina da UFMG e da Universidade de Itaúna, com o objetivo de disseminar conhecimento científico de qualidade, além de proporcionar aos alunos incentivo científico, com apresentações de pôster e temas livres. No evento, houve rica discussão sobre temas das três áreas de conhecimento abordadas, com presença de profissionais renomados em todos os dias de evento.
Использование импульсов микроволнового сверхизлучения для высокоградиентного ускорения электронов в цилиндрическом волноводе с диэлектрической вставкой
Authors: Данилов Ю.Ю. , Гинзбург Н.С. , Зотова И.В. , Яландин М.И.
Published: October 2021

We theoretically study the acceleration of electrons by a 38-GHz subnanosecond superradiance pulse with a 3-GW peak power in a cylindrical waveguide with an annular dielectric insert. It is shown that the energy gain and the accelerating gradient depend on the dielectric constant of the insert, namely, the energy gain decreases and the maximum accelerating gradient increases with increasing the dielectric constant. For an electron with an initial energy of 300 keV, the maximum accelerating gradient reaches 120 MV / m with an energy gain of 7.2 MeV in a waveguide with a polystyrene insert ( = 2.53) and 220 MV / m with an energy gain of 4.5 MeV in a waveguide with a quartz insert ( = 3.81).
Волоконно-оптический датчик на основе межмодового интерферометра с одномодовым подключением для одновременного измерения изгиба и растяжения
Authors: Маркварт А.А. , Лиокумович Л.Б. , Ушаков Н.А.
Published: October 2021

The article presents a fiber-optic sensor based on a singlemode-multimode-singlemode (SMS) structure for simultaneous measurement of strain and curvature. It is shown that the simultaneous demodulation of strain and curvature can be realized using the Fourier analysis of the recorded interference oscillations
Effects of Pain From Atopic Dermatitis: Interview and Focus Group Study With Patients and Their Families (Preprint)
Authors: Snyder Ashley M , Taliercio Vanina L , Brandenberger Adelheid U , Rich Bianca E , Webber Lisa B , Beshay Abram P , Biber Joshua E , Hess Rachel , Rhoads Jamie L W , Secrest Aaron M
Published: October 2021

BACKGROUND

Pain is an underappreciated symptom of atopic dermatitis that can affect the health-related quality of life (HRQL) of patients.

OBJECTIVE

The aim of this study is to understand the effect of pain on patients with atopic dermatitis and their family members and to recognize how this symptom affects HRQL.

METHODS

We conducted focus groups and interviews with patients with atopic dermatitis and their family members. Researchers independently coded the transcripts and reached a consensus on the major themes.

RESULTS

A total of 33 adult participants, consisting of 21 patients with atopic dermatitis (median age 47 years, range 22-77) and 12 family members (median age 50, range 22-72), attended either focus groups (23/33, 70%) or
interviews (10/33, 30%), where we assessed their experiences of pain. Four themes emerged in our study. Itchiness and pain can be intertwined: pain was often caused by or otherwise associated with itchiness and could result from open sores and excoriated skin. Characteristics of pain: pain was most often described as burning. Other descriptors included mild, persistent discomfort; stinging; and stabbing. Effects of pain: pain negatively affected various aspects of daily life, including choice of clothing, sleep, social activities, and relationships. The location of painful areas could also limit physical activity, including sex. Pain management: pain from atopic dermatitis could be managed to varying degrees with different over-the-counter and prescription treatments. Systemic agents that cleared the skin also resolved the pain associated with atopic dermatitis.

CONCLUSIONS

Pain can be a significant factor in the HRQL of patients with atopic dermatitis and should be considered by clinicians when caring for patients with atopic dermatitis.
Therapeutic Alliance in Web-Based Treatment for Eating Disorders: Secondary Analysis of a Randomized Controlled Trial (Preprint)
Authors: Stoeten Claudia , de Haan Hein Arnoud , Postel Marloes Gerda , Brusse-Keizer Marjolein , ter Huurne Elke Daniëlle
Published: October 2021

BACKGROUND

In face-to-face therapy for eating disorders, therapeutic alliance (TA) is an important predictor of symptom reduction and treatment completion. To date, however, little is known about TA during web-based cognitive behavioral therapy (web-CBT) and its association with symptom reduction, treatment completion, and the perspectives of patients versus therapists.

OBJECTIVE

This study aimed to investigate TA ratings measured at interim and after treatment, separately for patients and therapists; the degree of agreement between therapists and patients (treatment completers and noncompleters) for TA ratings; and associations between patient and therapist TA ratings and both eating disorder pathology and treatment completion.

METHODS

A secondary analysis was performed on randomized controlled trial data of a web-CBT intervention for eating disorders. Participants were 170 females with bulimia nervosa (n=33), binge eating disorder (n=68), or eating disorder not otherwise specified (n=69); the mean age was 39.6 (SD 11.5) years. TA was operationalized using the Helping Alliance Questionnaire (HAQ). Paired t tests were conducted to assess the change in TA from interim to after treatment. Intraclass correlations were calculated to determine cross-informant agreement with regard to HAQ scores between patients and therapists. A total of 2 stepwise regressive procedures (at interim and after treatment) were used to examine which HAQ scores predicted eating disorder pathology and therapy completion.

RESULTS

For treatment completers (128/170, 75.3%), the HAQ-total scores and HAQ-Helpfulness scores for both patients and therapists improved significantly from interim to post treatment. For noncompleters (42/170, 24.7%), all HAQ scores decreased significantly. For all HAQ scales, the agreement between patients and therapists was poor. However, the agreement was slightly better after treatment than at interim. Higher patient scores on the helpfulness subscale of the HAQ at interim and after treatment were associated with less eating disorder psychopathology. A positive association was found between the HAQ-total patient scores at interim and treatment completion. Finally, posttreatment HAQ-total patient scores and posttreatment HAQ-Helpfulness scores of therapists were positively associated with treatment completion.

CONCLUSIONS

Our study showed that TA in web-CBT is predictive of eating disorder pathology and treatment completion. Of particular importance is patients’ confidence in their abilities as measured with the HAQ-Helpfulness subscale when predicting posttreatment eating disorder pathology and treatment completion.
Willingness and uptake of the COVID-19 testing and vaccination in urban China: an online cross-sectional survey at early 2021 (Preprint)
Authors: Song Suhang , Zang Shujie , Gong Liubing , Xu Cuilin , Lin Leesa , Francis Mark R , Hou Zhiyuan
Published: October 2021

BACKGROUND

Regular testing and vaccination are effective measures to mitigate the ongoing COVID-19 pandemic. Few studies have focused on COVID-19 testing and vaccination uptake may change as the pandemic continues.

OBJECTIVE

To examine willingness and uptake of COVID-19 testing and vaccination during a low-risk period of the COVID-19 pandemic in urban China.

METHODS

A cross-sectional online survey was conducted among 2244 adults in urban China. Descriptive analyses were performed to compare the respondents’ willingness and uptake of COVID-19 testing and vaccination. Multivariate logistic regressions were fitted to investigate the factors associated with willingness and uptake of the two measures.

RESULTS

In early 2021, 52.45% of the respondents had received or scheduled a COVID-19 test at least once, and a majority (95.63%) were willing to receive testing. 63.28% of the respondents had received/scheduled or were willing to receive a COVID-19 vaccine. Willingness and uptake of COVID-19 testing were not associated with socio-demographic characteristics, except for occupation. Being of older age, migrants, having higher educational attainment and secure employment were associated with a higher uptake of COVID-19 vaccination among the surveyed respondents, while willingness to vaccinate was consistent across socio-demographic characteristics among those who had not been vaccinated.

CONCLUSIONS

Chinese adults expressed almost universal willingness of COVID-19 testing and relatively low willingness of COVID-19 vaccination at the low-risk period of the COVID-19 pandemic, independent from their socio-demographic characteristics. Maintaining willingness of COVID-19 vaccination is key especially when the pandemic evolved into a low-risk period.
Social Determinants in Self-Protective Behavior Related to COVID-19: Association Rule–Mining Study (Preprint)
Authors: Urbanin Gabriel , Meira Wagner , Serpa Alexandre , Costa Danielle de Souza , Baldaçara Leonardo , da Silva Ana Paula , Guatimosim Rafaela , Lacerda Anísio Mendes , Oliveira Eduardo Araújo , Braule Andre , Romano-Silva Marco Aurélio , da Silva Antônio Geraldo , Malloy-Diniz Leandro , Pappa Gisele , Miranda Débora Marques
Published: October 2021

BACKGROUND

Human behavior is crucial in health outcomes. Particularly, individual behavior is a determinant of the success of measures to overcome critical conditions, such as a pandemic. In addition to intrinsic public health challenges associated with COVID-19, in many countries, some individuals decided not to get vaccinated, streets were crowded, parties were happening, and businesses struggling to survive were partially open, despite lockdown or stay-at-home instructions. These behaviors contrast with the instructions for potential benefits associated with social distancing, use of masks, and vaccination to manage collective and individual risks.

OBJECTIVE

Considering that human behavior is a result of individuals' social and economic conditions, we investigated the social and working characteristics associated with reports of appropriate protective behavior in Brazil.

METHODS

We analyzed data from a large web survey of individuals reporting their behavior during the pandemic. We selected 3 common self-care measures: use of protective masks, distancing by at least 1 m when out of the house, and handwashing or use of alcohol, combined with assessment of the social context of respondents. We measured the frequency of the use of these self-protective measures. Using a frequent pattern–mining perspective, we generated association rules from a set of answers to questions that co-occur with at least a given frequency, identifying the pattern of characteristics of the groups divided according to protective behavior reports.

RESULTS

The rationale was to identify a pool of working and social characteristics that might have better adhesion to behaviors and self-care measures, showing these are more socially determined than previously thought. We identified common patterns of socioeconomic and working determinants of compliance with protective self-care measures. Data mining showed that social determinants might be important to shape behavior in different stages of the pandemic.

CONCLUSIONS

Identification of context determinants might be helpful to identify unexpected facilitators and constraints to fully follow public policies. The context of diseases contributes to psychological and physical health outcomes, and context understanding might change the approach to a disease. Hidden social determinants might change protective behavior, and social determinants of protective behavior related to COVID-19 are related to work and economic conditions.

CLINICALTRIAL

Not applicable.
Application of Ultrasonic-Assisted Fractionation with Full-Factorial Design for the Production of Alkaloid-Rich Fraction from Ficus septica Leaves
Authors: Hafizh Ridho Muhammad , Puspitasari Gani Andayana , Wahyuono Subagus , Fakhrudin Nanang
Published: October 2021

Ficus septica Burm. F (Awar-awar) in Indonesian herbal medicine traditionally used for the treatment of various disease. Previous studies indicated that the F. septica leaves contained phenantroindolizidine alkaloids with anticancer activity. Fractionation of the ethanol extract of F. septica leaves using n-hexane was able to separate chlorophylls and other inert non–polar constituents from the extract. This fractionation process can be optimized using ultrasonic-assisted fractionation to yield n-hexane insoluble fraction (HIF) that is rich in alkaloids. This study aimed to produce HIF from the ethanol extract of F. septica leaves by using optimized ultrasonic-assisted fractionation with n-hexane as a solvent and full factorial as experimental design. Ficus septica leaves were macerated in ethanol (60%) and the extract was used for the ultrasonic-assisted fractionation process. The duration of fractionation (5-30 minutes), the extract : n-hexane ratios (1:0.1 - 1:1.66 ml/ml), and the ultrasonic power (21-106 Wrms) were optimized to determine the optimal condition for each variable. These optimal variables were used for the production of HIF from the extract by using full factorial design in the ultrasonic-assisted fractionation process. The total alkaloid content was measured using spectrophotometry and was used as parameter for the optimization process. We found that the optimal condition for the fractionation process based on each single variable optimization were 5 minutes of the fractionation duration, 66-70Wrms of the ultrasonic power, and 1:0.7 - 1:0.8 of the extract : n-hexane ratio. By using these optimized variables, the ultrasonic-assisted fractionation using full factorial design yielded up to 0.035% total alkaloid content which is almost double from those in the extract (0.019%). This study provided a basic experimental model for the production of alkaloid-enriched HIF from F. septica leaves in the industrial or pilot scale, and might contribute to the development of Indonesian herbal medicine products from natural resources.
Multidisciplinary Synergy of Health Workers as an Effort to Improve Public Health Status
Authors: Yunita Ema Pristi
Published: October 2021

The low level of public knowledge of the importance of preventing diseases and maintaining health can increase morbidity and mortality. In this community service, counseling and integrated health services were provided by seven health study programs at Universitas Brawijaya (UB). This community service aimed to improve public health status and identify the correlation between education level and public behavior and their health condition. All health workers wrote the health status of the participants on the community health cards. The participants were asked to answer questionnaires as a feedback process and an analysis of the activity. A total of 95.33% of the participants stated that these activities were useful while 4.67% stated that the activities were useless. The results of the gamma correlation test showed a significant correlation between education level and public behavior towards complaints about aches and pains, coughs and colds, diarrhea, chest pains, and itching. On complaints about aches and pains and abdominal pain, the higher the education level, the worse the behavior in dealing with the complaints. Collaborative activities among health workers are needed to overcome public health problems. A high education level of the public does not always guarantee the accuracy of certain actions chosen to overcome various early symptoms of diseases. Therefore, the role of health workers is needed in providing health education to the public regardless of their education levels.
Application of Postharvest management of Corn to Support Integrated Farming System
Authors: Karyadi Joko Nugroho Wahyu , Ayuni Dwi , Bintoro Nursigit , Rahayoe Sri , Purwantana Bambang
Published: October 2021

Corn is a superior crop and its production centers are in the Grobogan and Pati Regency, Central Java Province, Indonesia. This plant is partly cultivated in farm fields and forest land owned by Purwodadi Forest Control Area (in Indonesia known as 'Kawasan Penguasaan Hutan – KPH) as an intercrop during re-planting of tropical hardwood, namely teak. Corn has become one of the significant side hustles for most of the residents in KPH with high incomes. Unfortunately, this high corn production was not accompanied by adequate postharvest technology. Some vital problems occurred, especially during raining season, like fungi, undesired germination, and many more. Therefore, the weight loss of corn production is still very high. This activity aimed to assist farmers by changing how farmers look at the quality assurance of the produced corn products and improving farmers' postharvest corn practices. This activity's method was introducing corn harvesting machines, namely corn sheller machines, and improving the farmers’ knowledge about the quality control of corn. The activities were carried out to allocate five (5) units of corn sheller units to five Forest Village Community Institutions (in Indonesia known as 'Lembaga Masyarakat Desa Hutan,' LMDH) who were the targeted partners. The activities of sharing the knowledge regarding good postharvest for corn were going well and the participants gave excellent responses and actively participated.
Poly-IgA Complexes and Disease Severity in IgA Nephropathy
Authors: Zhang Xue , Lv Jicheng , Liu Pan , Xie Xinfang , Wang Manliu , Liu Dan , Zhang Hong , Jin Jing
Published: October 2021

Background and objectives

Poly-IgA immune complex formation and glomerular deposition play a key role in IgA nephropathy. Our study sought to develop a new methodology for one-step serologic detection of poly-IgA levels.

Design, setting, participants, & measurements

A novel ELISA method using recombinant CD89 as a “capturing” probe was established for detecting poly-IgA immune complex in plasma. We applied semiquantitative measurements of these poly-IgA indices in patients recruited at Peking University First Hospital who had IgA nephropathy or other kidney disease types, as compared with healthy controls. The longitudinal trend of the poly-IgA index and the association with pathologic parameters and treatment responses were evaluated. Finally, we analyzed the molecular composition of poly-IgA complexes in patients by mass spectrometry.

Results

Recombinant CD89–mounted ELISA plates specifically captured plasma poly-IgA. The levels of poly-IgA immune complex (26.7 [interquartile range (IQR) 17.1–42.6] U/ml) in IgA nephropathy were significantly higher than those in healthy controls (15.5 [IQR 10.7–20.0] U/ml; P<0.001) or in controls with non-IgA nephropathy disease (14.8 [IQR 10.5–21.9] U/ml; P<0.001). Higher levels of poly-IgA immune complex were associated with lower eGFR and worse kidney outcome. Accuracy parameters and concordant statistics showed good discrimination between IgA nephropathy and healthy controls based on poly-IgA index levels (area under the curve [AUC], 0.78; 95% confidence interval [95% CI], 0.72 to 0.83; P<0.001), significantly outperforming galactose-deficient IgA1 levels (AUC, 0.70; P=0.05). Corticosteroid and immunosuppressant treatments lowered poly-IgA indices. After a recombinant CD89–directed workflow in conjunction with mass spectrometry, we also analyzed the molecular composition of IgA immune complex in patients with IgA nephropathy.

Conclusions

Higher level of recombinant CD89–bound poly-IgA immune complex was associated with the severity of the disease and with treatment response to steroids and immunosuppressants.
Explicaciones escolares respecto al concepto reactivo limitante
Authors: Iturra Toledo Monica Andrea , Mallea Lobos Javier Ignacio , Quintanilla Gatica Mario Roberto , Chen Carrillo Yo-Ying , Herrera Melin Ana María
Published: October 2021

El objetivo principal es analizar explicaciones que elaboran estudiantes de primer año de educación secundaria respecto al concepto de reactivo limitante. Dichas explicaciones se utilizan para identificar dificultades y concepciones alternativas asociadas al aprendizaje del concepto, derivadas principalmente del enfoque algorítmico de la enseñanza. Para evaluar las consecuencias de este enfoque, se indaga en las percepciones que tiene el estudiantado hacia el aprendizaje de la química. Los resultados obtenidos demuestran una tendencia de tipo explicación descriptiva, basada principalmente en conocimiento cotidiano.
Wall-E: Ciencia en contexto para formar docentes
Authors: Palacios Alicia , Pascual Virginia , Moreno-Mediavilla Daniel
Published: October 2021

Este artículo presenta la implementación y análisis de una propuesta didáctica para la formación de docentes de ciencias en un aula virtual. La propuesta utiliza la película Wall-E como recurso educativo que permite enfrentar al profesorado ante una enseñanza contextualizada y reflexiva de la ciencia. Los resultados de la intervención didáctica, el pre-test post-test, y la encuesta de satisfacción, indican que la propuesta ha conseguido aumentar el interés del profesorado por el uso de contextos a través del cine, y fomentar el uso de CSC para promover la reflexión en el aula de ciencias. Sin embargo, este cambio de percepción no se ve reflejado en un uso más innovador de estas estrategias en el aula.
Los modelos materia, reacción química y termodinámica como núcleos estructurantes de una química escolar orientada a la formación ciudadana
Authors: Marzábal Ainoa , Delgado Virginia , Moreira Seguel Patricia , Merino Rubilar Cristian , Cabello Valeria , Manrique Franklin , Soto Alvarado Macarena , Cuellar Fernández Luigi , Izquierdo Daniel
Published: October 2021

El presente trabajo propone considerar los modelos como núcleos estructurantes de la Química escolar, con el objetivo de superar los desafíos curriculares actuales y orientar la educación química hacia la formación ciudadana. Mediante un análisis de la literatura existente en el ámbito de la organización curricular de la Química escolar, se identifican los modelos materia, reacción química y termodinámica como los núcleos de la Química Escolar y se caracterizan estos modelos mediante las condiciones, entidades, propiedades, actividades y organización que se espera incluyan las representaciones de los estudiantes sobre los sistemas materiales, para razonar sobre un conjunto de hechos relevantes para la formación de ciudadanos.
Los retos de la enseñanza de Química en la pandemia de COVID-19: la metodología flipped classroom adaptada para el modo virtual en Brasil
Authors: Oliveira de Freitas Augusto Gonzaga , Brasil Irala Valesca , Maciel Bordin Daniela
Published: October 2021

La llegada de la pandemia COVID-19 impuso una serie de restricciones a escala global. Una nueva dinámica social se tuvo que adoptar en todo el mundo, en un intento por contener sus efectos. Las actividades docentes, como no podía ser de otra manera, también tuvieron que adaptarse a la realidad totalmente virtual, como consecuencia de la necesidad de distanciamiento social. Uno de los principales desafíos fue implementar la enseñanza virtual de manera que llegara a toda la comunidad académica. Desde entonces, se han adoptado diferentes metodologías para satisfacer las demandas de los más variados contextos. En este texto reportamos el uso de la metodología flipped classroom (que se traduce como clase invertida) en dos asignaturas de Química General, adaptadas a la modalidad virtual, en el contexto de una universidad federal brasileña. Se evaluó la percepción de los estudiantes sobre la metodología y el trabajo de tutoría desarrollado en uno de los grupos. Los resultados muestran que el aula invertida se puede adaptar a la realidad totalmente virtual, siendo favorecida de diversas formas por el trabajo de tutoría.

 
Percepción de los alumnos de química sobre el cambio de modalidad educativa en la pandemia por COVID-19
Authors: Reyes-Cárdenas Flor De María , Ruiz-Herrera Brenda Lizette , Llano-Lomas Mercedes Guadalupe , Lechuga-Uribe Patricia Alejandrina , Mena-Zepeda Margarita
Published: October 2021

Este trabajo presenta y analiza la percepción de los estudiantes sobre la estrategia educativa implementada a raíz de la pandemia de COVID-19, durante el periodo académico de marzo a junio de 2020, para las asignaturas teórico-prácticas Química General 1 y 2. Se preguntó a los alumnos respecto a su desempeño académico, aprendizaje, nivel de atención, capacidad de independencia y autoaprendizaje, así como sobre los obstáculos a los que se enfrentaron para acceder a las clases virtuales. En opinión de los alumnos los contenidos teóricos se abordaron de forma adecuada gracias a la guía del docente y a la diversidad de herramientas utilizadas; a su vez, expresan la evidente necesidad de cursar el laboratorio de forma presencial.
Diseño, aplicación y resultado de una estrategia de ludificación como actividad de cierre en clases de química
Authors: Lozano Lucia Oscar Raúl , Sánchez López de Andujar Alicia
Published: October 2021

Este trabajo se basa en la premisa de la falta de interés del alumnado por las ciencias, desencadenada en parte por las metodologías de enseñanza que utiliza el profesorado. Se profundiza en el concepto de ludificación (más conocido por el anglicismo de gamificación) y especialmente en la aplicación de actividades de tipo Cuarto de Escape en el entorno educativo. Se diseña una actividad de ludificación de este tipo, donde se trabajan conceptos que pertenecen al bloque de contenidos de “la materia” del currículo de Física y Química de 4º de ESO de España (15-16 años) con evaluación del resultado del juego por parte de los estudiantes y los docentes. Esta actividad trata conceptos que el alumnado ya ha estudiado anteriormente, por lo tanto, puede ser considerada como una actividad final, de cierre, o de evaluación de los conocimientos de la materia. En la actividad, además, se introduce la visión de una ciencia contextualizada respecto a la historia y a la actualidad (CTSA). 
Conocimientos del profesorado universitario sobre la enseñanza de la química con laboratorios remotos
Authors: Idoyaga Ignacio Julio , Vargas-Badilla Laura , Moya Cesar Nahuel , Montero-Miranda Eric , Maeyoshimoto Jorge Esteban , Capuya Fernando Gabriel , Arguedas-Matarrita Carlos
Published: October 2021

El trabajo presenta un estudio exploratorio cuyo objetivo es describir y caracterizar el conocimiento declarativo sobre la enseñanza de Valoración Ácido Base con Laboratorios Remotos de un grupo de nueve profesores de química de la Universidad de Buenos Aires. Estos dispositivos permiten realizar actividades experimentales reales remotamente en cualquier momento y desde cualquier lugar. La metodología incluyó el diseño de un cuestionario de preguntas abiertas. Para la revisión de datos se recorrió a algunos aspectos del análisis del contenido y a categorías generadas de acuerdo a los lineamientos de la teoría fundamentada. Los principales resultados mostraron que los profesores sostienen aproximaciones didácticas vinculadas a los protocolos tipo receta y a la mimesis, que consideran intuitivos a los Laboratorios Remotos y que priorizan la enseñanza de los contenidos conceptuales. A modo de conclusión puede decirse que los profesores conciben el trabajo con laboratorios remotos de manera similar a los trabajos prácticos tradicionales. Como perspectiva se plantea que queda inaugurada una línea de investigación, centrada en el conocimiento del profesorado, que deberá incorporar nuevas y variadas estrategias metodológicas. 
Magnetic parameters and palaeoclimate: A case study of loess deposits of North-East of Iran
Authors: Alimohammadian Habib , Haskouei Fereshteh Mahdipour , Sabouri Jafar
Published: October 2021

Environmental magnetism techniques enable us to reconstruct paleoclimate conditions in some deposition such as losses. The  magnetic properties  of  minerals  are  used  as  proxies  for  environmental  changes. For this study, loess/paleosol sequence of Kolet section at Neka, north-east of Iran were magnetically investigated. We applied environmental magnetism methods, to reconstruct paleoclimate changes. We investigated relationship between paleoclimate changes and environmental magnetism proxies like magnetic susceptibility (?) variation. The laboratory techniques indicated the presence of main factor of magnetic property in loess/paleosol sequence, such as magnetite, maghemite and etc. We also estimated magnetically parameters (like SIRM, HIRM and etc.) to confirm concentrations of both aeolian and pedogenic particles versus variations of magnetic susceptibility enhancement. The ? values show prominent peaks for the three well developed soil and paleosol horizons, Recent Soil (S0), Upper Paleosol (S1) and Lower Paleosol (S2); which refer to warmer and wetter conditions. As result, we concluded that the increase/decreasing of magnetic susceptibility is coinciding with palaeosol/loess sequence, and probably with humid/arid conditions. Moreover, variations of magnetic susceptibility versus lithological column of Kolet section enabled us to recognize paleoclimatically periods known as interglacial/glacial cycles. The obtained  magnetic  data  indicate  that  during over  the  past  50  ka,  there  have  been  at  least  two glacial/interglacial periods and since last 20 ka, there was no main glaciation occurrence, in the study area.