bluuebunny/crossref_metadata_2025 huggingface dataset:
Design and control system of temperature and water level in hydroponic plants
Authors: Azhari  , Simanjuntak Dervin , Hakim Lukman , Sabar
Published: February 2022

Agricultural cultivation technology with a hydroponic system is expected to be an alternative for people who have limited land or yards. However, manual control cannot be done at any time due to business and other work, so a controller is needed to monitor and control the temperature and water level in hydroponic plants to avoid the death of plant. The purpose of this research is to create a temperature and water level control system for hydroponic plants. The control process uses a NodeMCU esp8266 microcontroller. The process of data communication carried out by hardware and software using wireless media. The water temperature detection system uses a DS18B20 sensor, while the water level sensor uses an ultrasonic HC-SR04. The results of this study the system as a whole can perform the process of monitoring and controlling the temperature and water level in hydroponic plants automatically and displayed on the LCD and android. When the water level is less than the minimum limit of 5 cm, the filling pump will be active and it will take about 6.48 minutes to fill the reservoir from an empty state. In the temperature control system, an average error of 3.71%. In this research is obtained if water temperature is more than 29°C, the cold water pump will be active and it will take about 2 minutes to circulate the water back to 28°C.
Development of cigarette butt fibre filter reinforced by opefb fiber composite material for trash can
Authors: Lubis Riadini Wanty , Yani M. , Siregar Chandra Amirsyah Putra , Gunawan Safri
Published: February 2022

This research developed new materials from cigarette fibre filter and OPEFB fibre. This study to develop polymer composite compositions with varying strengths and to perform flexural tests and specimens that best represent the properties used in waste basket products. The method used is to use variation compotiton to determine the best mechanical response generated by testing the specimen. The material used is made from composite, cigarette fibre filter and addition of OPEFB fibers is used as a filler and polyurethane as the matrix. The results are informating that of the best material properties chosen to be developed in to product of a trash can. The conclusion of this study is that the increase in the percentage of reinforcement is directly proportional to the resulting stress and strain values. In addition, it is recommended to use specimen C as a polymer composite material with optimal mechanical properties for product development as waste.
Analysis of hybrid power plant scheduling system diesel/photovoltaic/microhydro in remote area
Authors: Hutasuhut Abdul Azis , Rimbawati  , Riandra Juli , Irwanto M.
Published: February 2022

Currently, diesel generators that are still operating must be hybridized with renewable energy in order to save fuel expenditure. In addition, the generator scheduling system is also a solution to save fuel. This study aims to schedule the operation of a hybrid power plant diesel/photovoltaic/microhydro in the village of Rumah Sumbul in serving the load needs in order to obtain the best and economical system combination that is able to serve the needs of a continuous electrical load. Based on the results of the analysis using HOMER, the scheduling in the first scenario of diesel/microhydro is able to produce electrical energy of 35.6 MW/year. For the second scenario, the diesel/photovoltaic operation is capable of producing 12.20 MW of electrical energy/year. The two hybrid power plants have met the target for electricity production of 2 MW/year. Furthermore, the economical side of the diesel/microhydro combination is cheaper with operating costs of 467,545,800 IDR for 25 years with a profit of 601,150,000 IDR during the project, where the return on capital occurs in the 13 th year. operational costs of IDR 2,885,597,000 for 25 years with a profit of 607,009,000 IDR during the project in progress and a return on investment in the 13th year.
Stainless steel foam as wick material in heat pipe for electronics cooling application
Authors: Ginting Fitri H S , Humaidi Syahrul , Tetuko Anggito P
Published: February 2022

In this preliminary investigation, we analyzed the possibility using a stainless steel foam as a wick material in heat pipe. The heat pipe will be used as a passive cooling sytem in electronic devices. Stainless steel foam that used in the current investigation is a commercial foam that has been treated to be characterized using SEM and 3D optical microscope. Analytical models were also developed to calculate the capillary pressure and effective thermal conductivity of the stainless steel foam. The analytical model revealed that the optimum stainless steel foam to be used as wick material is found at the pore size, porosity and contact angle of 30 μm, 0.1 and 0°, respectively.
Simulation of induction motor behavior under voltage sags using alternative transient program
Authors: Hardi Surya , Sembiring R. , Rachmad Muadzzah , Rohana  , Nisja I.
Published: February 2022

The primary source of voltage sags is a short circuit fault in the power system. Three-phase fault can result in a more severe effect on the equipment. The voltage sags have affected significantly on performance degradation of the induction motor. The motor behaviors can be investigated in terms of rotation speed, torque, peak current, and recovery time during and after voltage sags. This study is to investigate induction motor behavior under voltage sags using the alternative transient program (ATP) draw software in simulation models. Distinct rated capacity, mechanical inertia, and loads torque (constant, linear, and variable) of the motor were used to investigate the motor’s behavior during and after sag end. Voltage sags resulted from three-phase fault at the certain locations in industrial power systems. The motor rotation speed decreases in slightly distinct during voltage sag but recovery times required to motors are longer for the large capacity motors. The large motors create the larger inrush current can reach more than five times its nominal. The motors with constant load toque subjected to voltage sag lead loss control in speed.
Design grounding grid resistance of substation for two soil layer model
Authors: Hardi Surya , Nasution Azwar , Harahap R. , Fitriani Ayu
Published: February 2022

All Grounding planning of a substation is important and various design applications are available using calculation uniform soil resistivity, even though actual resistivity data measured is more than one layer. This is caused by limited availability of the application in processing data only for resistivity one layer. Substation grounding grid application (ASPG) 1.0 can be used for designing grid grounding. The ASPG was developed from Lab View software and has ability to data process for resistivity two-layer that to refer IEEE Std. 80-2013. Grid grounding resistance is considering a combination of grid conductor and ground conductor. This paper discusses the calculation of the magnitude of substation grid grounding using formulas developed by Schwarz, Sulivan and Sunde. The design result obtained is more accurate in substitute resistivity for resistivity two-layer model and calculation grounding resistance substation.
Impact of small hydro generation on voltage profile and losses in 20 kV distribution network
Authors: Adhere L. , Syafruddin Ir. , Sinulingga Emerson P.
Published: February 2022

Planning in the development of electricity availability focuses on Renewable Energy power plants in support of the Government’s strong determination to suppress fossil-based energy and increase in New Renewable Energy whose mix is targeted to reach 23% in 2025. Distributed generation (DG) is one of the new approach in the installation of power plants which the plant location is no longer centralized, but it was spread on the distribution of electricity networks. Nowadays, the application of distributed generation has increased because it is a renewable energy especially small hydro of distributed power plants can affect the conditions of the distribution network. Therefore, it is necessary to know the impact of the installation of distributed power plants. This study was conducted to analyze the effects of DG connected to network at two conditions First, the distributed generation connect when under load condition in network and second, distributed generation connect when peak load condition in network. Simulation in this study was conducted using the ETAP software and The Newton-Raphson method has been used in order to calculate power losses and voltages across the network with real data of rural distribution network in Tanah Jawa, North Sumatera, Indonesia. The 20kV distribution network was used in this feeder, and it was divided into one main feeder. The results of this study are expected to provide information about the impact of the DG on voltage and power losses in distribution network. The results of the study show that the installation of DG enhances the voltage profile and ready for installation Small Hydro as DG.
Monolith solid porous carbon approach derived from Garcinia Xanthochymus for high-performance electrode material of supercapacitor
Authors: Taer Erman , Chow Sielvya , Apriwandi
Published: February 2022

Monolith solid porous carbon approach was prepared from biomass based from Garcinia Xanthochymus by using a high-temperature pyrolysis both of carbonization and physical activation in one stage integrated stage. Effect of the chemical impregnated of the activated carbon was studied. The N2 gas environment was used as inert gas of carbonization, and the CO2 gas was used as a physical activation atmosphere. The dimension of solid coin porous carbon was evaluated in the before and after high-temperature pyrolysis based on reduction of mass, diameter, and thickness. Furthermore, the porous carbon obtained also reviewed microstructure properties by using X-ray diffraction technique. Moreover, the electrode materials were evaluated their electrochemical performances at cyclic voltammetry (CV) and galvanostatic charge discharge (GCD) in different scanning rate of 1, 2, 5, and 10 mV s−1, at window voltage of 0.0-1.0V and current density of 1.0 A g−1. The optimum capacitive properties were found as high as 159 F g−1 at aqueous electrolyte of 1 M H2SO4. The energy density was reviewed of 9.91 Wh kg−1 at optimum power density of 97.17 W kg−1.
Characterization of hydroxyapatite by cytotoxicity test and bending test
Authors: Sirait M , Sinulingga K , Siregar N , Doloksaribu M E , Amelia
Published: February 2022

Hydroxyapatite has been synthesized as a bone graft material by analyzing the membrane made according to the cytotoxicity test and bending test. The method used is dry ball milling. Cytotoxicity testing was carried out by making isolated osteoblast cells cultured in a 75 cm2 cell flask containing a minimum of essential media. Based on the cytotoxicity test, it was found that hydroxyapatite is not toxic with cell viability above 60% (non-toxic requirements ISO 10993-5). From the variation of the hydroxyapatite mixture used, the average cell viability was (100.48 ± 11.98)%. A mixture of 2.5% Ag and 5% Ag with hydroxyapatite also provides good viability, which is above 60%, which means it is not toxic. The results of the analysis of the bending test and the compressive test showed that the larger the hydroxyapatite mixture, the lower the bending and compressive test results. The maximum bending test on a 10% mixture is 22.1 M.Pa and the compressive test on a 5% mixture is 16 °ShD.
Rolling uphill experiment – a close look and explanation
Authors: Wirjawan Johannes V.D. , Founda Noviani Elisabeth Pratidhina
Published: February 2022

Rolling uphill experiment is one of fascinating experiments that easily attracts students’ attention due to its contradictory with common sense. Although it has been explained qualitatively, explicit explanation of the phenomenon is hardly found. In this study the researchers will describe the detail setting of the experiment and quantitatively set the formula to ascribe the relationship amongst the involved variables which allow the rolling uphill happens. It turns out that the relationship among the involved variabloes is a simple one and can be easily understood.
The use of thermo electric generator to utilize the waste heat from the biomass stove into electricity
Authors: Tambunan B H , Simanjuntak J P , Koto I
Published: February 2022

Indonesia has a huge potential for biomass energy resources. In 2013, the estimated potential of forest biomass in Indonesia for bioenergy was 132 PJ, 50.4% from harvest residues and 49.6% from wood processing residues. Until now, the technology of burning biomass using a stove continues to develop. Biomass stoves are designed, modified and tested to get maximum performance, at least approaching the performance of LPG-fueled stoves. Several studies concluded that about 14.66% of the total heat loss is on the walls of the biomass stove. The purpose of this study was to investigate whether the waste heat in the wall of a biomass stove can be used to generate electricity. Many researchers have studied the heat loss on the walls of the biomass stove, this heat loss can reduce the thermal efficiency of the stove and can cause the stove user to feel uncomfortable. Based on the Seebeck effect method where the temperature difference can be converted into electricity. If there is a temperature difference between the two sides of the thermoelectric, electricity will arise. This principle is used by thermoelectric generators. To maximize the temperature difference, the cold side of the Thermoelectric Generator (TEG) needs a cooling system. In this study, the TEG was attached to the wall of the biomass stove, then the voltage generated by the TEG was measured for each type of biomass fuel. the highest average voltage produced by wood chips, followed by candlenut shells, corn cobs and coconut shells. This is unique, although the calorific value of coconut shells (19,5 MJ/kg) is higher than hard wood (18,8 MJ/kg) and corn cobs (5.32 MJ/Nm3), but the highest average voltage is produced by wood 1.30 volts, then 1.12 volts of candlenut shells, 1.08 volts of corn cobs, and 0.79 volts of coconut shells.
Microplastic waste polluted water measurement development based on parameter of physics
Authors: Indrasari W. , Sakinah F. , Umiatin U.
Published: February 2022

Currently, microplastics are detected in almost all water areas of the world. Hundreds of tons of microplastic waste produced and disposed of in the waters impact tissue damage and reduce water quality. A measurement system for detecting water polluted by microplastic waste based on the parameter of physics has been developed. This developed system is composed of a water pH sensor, salinity sensor, conductivity sensor, magnetic sensor, and Arduino Uno as the control system. The sensor characterization was carried out using standard tools to determine the sensitivity of each sensor. This process found that the sensitivity of the water pH sensor, water conductivity sensor, magnetic field sensor, and salinity sensor was -0.1702 V/pH, 0.9 mV/ppm, 0.0018 V/Gauss, and 0.1905 V/PPT, respectively. The prototype measured these parameters in synthetic wastewater and natural water samples contaminated by microplastic waste. Synthetic wastewater is a mixture of water, salt, and scrub with different concentrations. Meanwhile, the natural sample water originates from seven rivers around the Jakarta area. This system is equipped with an HC-06 Bluetooth module to transfer measured data to the Android application to be monitored directly by the smartphone..
Prototype of water level monitoring system using magnetic sensor and ultrasonic based on Arduino Mega 2560
Authors: Indrasari W , Kadarwati L V
Published: February 2022

Water level monitoring is an activity to observe the water level by identifying and anticipating flood problems that will arise for action to be taken as early as possible. This system is connected by water level measurement. This prototype uses two types of sensors to measure the water level, the UGN3503 magnetic sensor will detect the water level horizontally, and ultrasonic sensors will detect vertically. Arduino Mega 2560, as a control system, regulates the work of the integrated sensors. The experiment using one UGN3503 sensor is obtained the maximum deviation on the addition or reduction of water by 3 mm. The overall system experiment shows that the measurement results of the UGN3503 sensor are closer to the actual height than ultrasonic. The data region affected by the water overflow is processed in ArcGIS software to predict that area. The relationship between height alterations to the overflow area is described in a linear equation.
Evaluation of trashrack replacement design for malalo intake of singkarak hydro power plant in west Sumatera
Authors: Kurniawan Elfin , Simaremare ArionmaroAsi
Published: February 2022

Singkarak hydro power plant (SHPP) with the capacity of 175 MW provide essential supply to Sumatera Interconnection System thus reliable and efficient operation of the hydro power plant component must be maintained. With the damaged experienced by the trash rack during Padang earthquake, the operation of the power plant was disturbed and replacement of trash rack need to be executed. This study evaluate the modification of trash rack replacement in terms of head loss, potential energy and revenue losses. This simple evaluation finds that the replacement design gives lower head loss which translated to lower energy and revenue losses. The potential energy and revenue losses also increase exponentially with the increase of trash rack blockage. This result amplify the importance of trash rack design and cleaning during operation of a hydro power plant.
Impact of the HFC migration to FTTH on the efficiency and reliability of the internet provider services business (A case Study)
Authors: Khalil  , Siregar Marsul , Sihombing Denny
Published: February 2022

This paper presents the impact on the efficiency, reliability, and quality of the Internet provider services due to the migration of the Hybrid Fiber Coaxial (HFC) to the Fiber To The Home (FTTH) infrastructure. The implementation of the emerging technology on communication caused an increase in the internet service provider business competition and it makes the company that engaged in this field will compete to provide the best service to the customers as especially on the efficiency and reliability of the services to whom using the FTTH. The comparison and analysis of the impact of the HFC stand-alone to the FTTH technology migration process on both of the customers sides as well as the Network Availability and the percentage of uptime (connection to the ISP’s) of customer devices are provided. In this case study, it is found that the infrastructure cost of the technology HFC system is cheaper about 53.93 percent than the technology FTTH system. However, from a reliability perspective, FTTH is much better than HFC. It is found that the impact of the migration from HFC to FTTH shows the yearly Network Availability was 98.635 percent with a downtime of 2,819,473 minutes. And it provides an increase of Network Availability after construction (during commissioning or acceptance test). In addition, it was found that the correlation between uptime/downtime before migrating during employed the HFC technology, there were many problems caused by power supply problems and high losses of the coaxial cable. So if the coaxial cable is replaced by the fiber optic cable, will be there is an increase in the availability of the Network Availability during 2020 by 1.301 percent. Also by takeout the FDT on the FTTH, it is predicted that the cost reduction about 10 percent, faster implementation for the schedule and fewer cables maintain.
Motion control development for autonomous ground robots in agriculture task
Authors: Latif M. , Hardi Shofia , Herawati Sri
Published: February 2022

Motion control for autonomous ground robots to solve tasks in agriculture is investigated in this study. Motion control is designed and developed to track the reference trajectory. The model is developed in detail based on the kinematics and dynamics of the robot. The novelty of this research is to solve the problem of controlling agricultural robots on the problem of tracking a rectangular spiral trajectory. The motion controls described in this study were developed and validated in a simulation. Accuracy of the developed system is validated by measuring the error tracking using MSE and RMSE. Conclusion shows that the developed motion control for autonomous ground robots works well based on the validation results.
Development of PISA-based test on mechanical wave material in senior high school
Authors: Baiziah Destri , Sahyar  , Derlina
Published: February 2022

This study aims to develop a PISA-based test on mechanical wave material in high school in accordance with good test qualification standards in terms of validity, reliability, level of difficulty, discriminatory power and effectiveness of distractors. The type of research is development research, using the ADDIE model. The data analysis technique used is qualitative and quantitative. The results of qualitative analysis, the quality of the PISA-based test is very good with a percentage of validity of 84.75% based on the results of validation by 5 experts who are reviewed in terms of material, construct and grammar. Quantitative analysis of the quality of the PISA-based test are good. Analysis of 38 items in the small group test obtained 36 items accepted and 2 items rejected. The large group test obtained: (1) 32 valid items (88.89%), 4 invalid items (11.11%). (2) the reliability of the tests is included in the Very Good category with a value of 0.839. (3) 4 (11.11%) questions in the easy category, 30 (83.33%) questions in the medium category and 2 (5.56%) in the difficult category. (4) The discriminatory power of questions obtained 1 (2.78%) questions in the very good category, 31 (86.61%) questions in the good category and 4 (11.11%) questions in the bad category. (5) 32 (88.89%) items are effective and 4 (11.11%) items are ineffective. The items received were 30 (83.33%) questions, 2 (5.56%) items revised, and 4 (11.11%) items rejected.
Development of teaching materials like PISA for physics mechanical wave topic in high school
Authors: Fonna Nurdianita , Bunawan Wawan , Derlina
Published: February 2022

This study aims to describe the validity, practicality and effectiveness of physics teaching material like PISA. The method carried out in this study uses Research and Development (R&D) development research using the ADDIE model consisting of 5 main phases or stages, namely 1) Analyze (Analysis), 2) Design (Design), 3) Develop (Development), 4) Implement (Implementation), 5) Evaluate (Evaluation). Physics teaching materials developed in the form of teaching materials like PISA. The subjects in this study were students of class XI MIA I SMA Swasta Dharma Pancasila Medan. The results of the study obtained that the validity of teaching materials to the material by the validator obtained results from the content feasibility aspect of 88%, the language feasibility aspect by 86% and the presentation feasibility aspect by 87% while the validity of the teaching materials to the media by the validator obtained a result of 87% so that it met the category valid. The results of the effectiveness test show that teaching materials are effective for use in the learning process with a percentage value of 82% with a very effective category. The practicality of teaching materials in the very practical category of student responses obtained a percentage value of 90%. This shows that the physics teaching materials like PISA have met the valid, practical and effective criteria. And there is an increase in student learning outcomes in the good category after applying high school physics teaching materials like PISA.
Analysis of momentum and impulse on students’ creative thinking skill through project based learning integrated STEM (science, technology, engineering, mathematics)
Authors: Saputri Mawarni , Syukri Muhammad , Elisa
Published: February 2022

The aim of this study was to analyze students’ creative thinking skills on momentum and impulse material through Project based learning integrated STEM. The type of research used is a quasi experiment. The data analysis was carried out through ten creative thinking skills test in essay form. Before instrument test are tested on students, expert validation tests were carried out first. The creative thinking skill test indicators used consist of fluency, flexibility, originality and elaboration. The results of the study showed that the average value of students’ creative thinking skills are classified as creative category. Average percentage of students’ creative thinking skills scores for each indicator obtained are the lowest indicator is originality, while the highest indicator score is fluency. The implementation of Project based learning integrated STEM has a positive impact in improving students’ creative thinking skills especially in physics learning.
Interactive learning media innovation using lectora inspire solubility and solubility product materials
Authors: Lukman I , Silalahi A , Silaban S , Nurfajriani
Published: February 2022

This research aims to determine the feasibility level of interactive learning media using lectora inspire material solubility and solubility product which was developed based on the BSNP standard integrated interactive media. This type of research uses the Research and Development (R & D) method with the Analysis, Design, Development, Implementation, Evaluation (ADDIE) model. The instrument used is an interactive media integrated BSNP questionnaire given to one lecturer of technology science, one lecturer of chemistry education, and one high school chemistry teacher. The data was processed using descriptive statistics. The results showed that interactive learning media using lectora inspire material solubility and solubility product which was developed was very feasible to use reffering to the BSNP standard integrated interactive media with content feasibility of 4.8, and presentation feasibility of 4.9. This research was carried out only until the development stage.
The effect of reflector application for solar panel output improvement
Authors: Bintang Salman , Muhammad Aulia Rahman S , Sinaga Denny Haryanto , Dewy Mega Silfia , Tarigan Rizky Falmi Setiawan , Marpaung Paulinson Riki
Published: February 2022

The potential of solar energy as a renewable energy source is widely available in nature. Sunlight is abundant and even for tropical countries, the sun shines almost all year round. Therefore, solar power plants are very suitable for application in Indonesia. Solar electrical energy is generated by components called solar panels. This component converts energy from sunlight into electrical energy. Solar Reflector used in solar panels is a mirror. A plane mirror is a mirror that has a flat surface like a straight line, where one surface is coated with a reflecting metal so that the surface of the flat mirror can reflect more than 95 percent of the light that hits it. In this research, reflectors were added to the solar panels on the right and left sides. The reflector on the solar panel is shaped at an angle of 70 degrees. The reflector serves to optimize the light around the solar panel and focus the light towards the solar panel so as to produce greater output power. The highest voltage and watt are at 11.00 AM. 27 July 2021 is good condition for solar panels with average 19.63 V and 56.81 W.
Utilization of pineapple (ananas comosus l) leaves plant waste as a natural biosorbent
Authors: Herlinawati H. , Sihombing Junifa Layla , Kembaren Agus , Masdiana
Published: February 2022

The adsorption process is more suitable because the costs required are not too expensive and will not cause new contaminants. Currently, research is being promoted on the use of alternative adsorbents derived from nature. Natural adsorbents in addition to having good adsorption ability, are also more economical. Natural biosorbent from pineapple leaves (Ananas comosus L) which had previously been carried out with carbonation, biosorbent activation, and biosorbent characterization using XRD and BET instruments, respectively. The results of the XRD analysis characterization obtained the diffraction pattern of pineapple leaves carbon, there are several sharp peaks, which are very clear at a diffraction angle of 2θ between 25 to 65 degrees, with a crystallinity degree of 32% and pineapple leaves activated carbon, increased the number of degrees of crystallinity at a diffraction angle of 2θ between 20 to 65 degrees, with a degree of crystallinity of 42.26%. The results of the XRD analysis characterization showed that pineapple leaves biosorbent and pineapple leaves activated carbon had amorphous material structure. This material is composed of atoms that are arranged irregularly and randomly scattered. The results of the BET analysis characterization obtained that each graph meets the classification of type I, type II, and type V adsorption isotherms, it means that these carbons have the same type, namely micropores (< 2nm). The surface area according to BET data on pineapple leaves carbon was 70,418 m2/g and carbon activated had an outer surface area of 39,394 m2/g. Likewise with the results of BJH data, where the surface area of pineapple leaves carbon is 44,775 m2/g higher than carbon activated is 25,685 m2/g.
Industrial field work practice information system design
Authors: Syahputra Fahmy , Dalimunthe Amirhud , Sidabutar Uli Basa
Published: February 2022

The Faculty of Engineering, Universitas Negeri Medan requires the development of technology and communication in assisting performance and processes in carrying out their functions. Its development must produce benefits for the Faculty so that academic implementation runs smoothly, as well as assisting organizations in carrying out the required processes to help organizational managers make decisions. Changes in the form of the process used with the development of technology and communication are expected to encourage organizations to have better management.
Control optimal analysis of SEIR model of covid 19 spread in Indonesia
Authors: Rangkuti Y.M. , Firmansyah  , Landong A.
Published: February 2022

In this paper we use optimal control techniques, SEIR model of Covid 19 in case Indonesia, in order to establish vaccination, personal protective measures and treatment plans to control the spread of an infectious disease. We validate them by the use of the Maximum Principle. The findings revealed that the best practice of combining all three intervention measures considerably reduces the proportion of people who are exposed and symptomatic, as well as those who are asymptomatic.
Focal intensity landscapes of tightly focused spatially varying bright ellipse fields
Authors: Pal Sushanta Kumar , Kumar Singh Rakesh , Senthilkumaran P
Published: February 2022

Vector vortex beams play an important role in tailoring tightly focused fields by creating an additional longitudinal component at the focal plane. Until now, mainly focusing properties of fundamental, higher order vector fields and negative indexed ellipse fields have been investigated. In this paper we numerically analyze tight focusing behaviour of ellipse fields embedding C-point singularities of index

I
C

=
±

1
2

,

I
C

=
±
1

,

I
C

=
±

3
2

and

I
C

=
±
2

. We show that both the sign and absolute value of C-point index (I

C
) of the ellipse fields play an important role in tailoring the focal intensity landscapes. For negative index C-points the intensity distribution of the longitudinal components show symmetries that correspond to the number of separatrices present in the polarization distribution. At the focal plane, both transverse and longitudinal components of the ellipse fields are found to be embedded with phase singularities. These ellipse fields can be useful in advanced microscopy for shaping the focus of light fields for various applications.
The integrated contribution of surface topology to anti-icing effectiveness
Authors: Truong Mai Xuan , Hanh Vu Thi Hong , Nguyen Thanh-Binh
Published: February 2022

The effects of topology parameters at micro-scale on anti-icing performance have not been investigated theoretically and clearly. In this work, we figured out the affection of structure parameters and derived quantities to anti-icing performance in terms of adhesive strength. Well-textured silicon microstructure with different topologies and surface energies was generated via the lithography process. The parameters including pillar height, top diameter, and spacing were simultaneously investigated through the transition energy barrier approach. The results demonstrated the integrated contribution of all parameters in anti-icing performance, instead of independent effects. Furthermore, our results disclosed the correlation contribution of edge and top effects in adhesion strength. This insight should lead to an understanding of icing phenomena and the design of icephobic surfaces.
COVID-19 threatens faculty diversity: postdoctoral scholars call for action
Authors: Andrade Brenda , Medina-Munoz Hugo C. , Montaño Elizabeth T. , Roa Jinae N. , Sánchez Richard G. , Tat John , Hurst Samantha , Mouchka Morgan E. , Trejo JoAnn , Ramirez Monica L. Gonzalez
Published: February 2022

Despite substantial investment and effort by federal agencies and institutions to improve the diversity of the professoriate, progress is excruciatingly slow. One program that aims to enhance faculty diversity is the Institutional Research and Academic Career Development Award (IRACDA) funded by the National Institutes of Health/National Institute of General Medical Sciences. IRACDA supports the training of a diverse cohort of postdoctoral scholars who will seek academic research and teaching careers. The San Diego IRACDA program has trained 109 postdoctoral scholars since its inception in 2003; 59% are women and 63% are underrepresented (UR) Black/African-American, Latinx/Mexican-American, and Indigenous scientists. Sixty-four percent obtained tenure-track faculty positions, including a substantial 32% at research-intensive institutions. However, the COVID-19 pandemic crisis threatens to upend IRACDA efforts to improve faculty diversity, and academia is at risk of losing a generation of diverse, talented scholars. Here, a group of San Diego IRACDA postdoctoral scholars reflects on these issues and discusses recommendations to enhance the retention of UR scientists to avoid a “lost generation” of promising UR faculty scholars.
Interactive Beliefs about Genes and Behavior Predict Improved Sun Protection Following Melanoma Genetic Counseling
Authors: Aspinwall Lisa G , Drummond Danielle M , Stump Tammy K , Kohlmann Wendy K , Leachman Sancy A
Published: February 2022

Background

Little is known about how members of cancer-prone families think about genetic determinism and whether personal behavior can amplify or counter genetic risk for disease.

Purpose

Understanding how people think about the impact of personal behavior on disease risk may inform communications about genetic risks and their management.

Methods

We assessed three sets of beliefs about the impact of behavior on genetic risk—interactive (unhealthful behaviors can amplify genetic risk), subtractive (healthful behaviors can reduce genetic risk), and deterministic (genes primarily determine health outcomes)—among 114 unaffected members of melanoma-prone families receiving genetic counseling (51.6% men, average age = 35.3). We examined whether these beliefs predicted changes in perceived control, motivation to manage melanoma risk, and sun-protection behavior one year later.

Results

Participants strongly endorsed interactive and subtractive beliefs, but not deterministic beliefs. These beliefs generally did not change, even among those who received positive CDKN2A/p16 genetic test results conferring up to 76% lifetime melanoma risk. Controlling for age, sex, education, skin type, and genetic test result, interactive beliefs predicted sustained increases in perceptions of personal control, motivation to reduce sun exposure, use of multiple sun-protection methods, and reduction in objectively assessed tanning at the wrist one year following genetic counseling. Subtractive beliefs predicted increased personal control, motivation to manage risk, and sunscreen use, while deterministic beliefs were generally unrelated to outcomes.

Conclusions

Among people at highly elevated hereditary cancer risk, beliefs that unhealthful behaviors can amplify genetic risk seem to be especially motivating of behavioral risk-reduction efforts.
Describing transitions in residential status over 10 years in the very old: results from the Newcastle 85+ Study
Authors: Davies Laurie E , Brittain Katie , Wilkinson Heather , Lewis Sue , Robinson Louise , Kingston Andrew
Published: February 2022

Background

the very old (aged ≥ 85) are the fastest growing subpopulation of many developed countries but little is known about how their place of residence changes over time. We investigated transitions in residential status in an inception cohort of 85-year-olds over 10 years.

Methods

data were drawn from the Newcastle 85+ Study, a population-based longitudinal study of individuals aged 85 in 2006 (i.e. born in 1921) and permanently registered with a Newcastle or North Tyneside general practice (n = 849).

Results

76.3% lived in standard (non-supported) housing at baseline (age = 85) and few moved into a care home. The majority either remained in standard housing or died over the study period. A significant number who lived in standard housing had dependency and frailty at baseline.

Discussion

given the undersupply of care homes, and preference of older people to remain in their own homes as they age, the questions posed by this analysis are how to survive to 85 and remain in standard housing until the age of 85? And how, and by whom, are such a group being supported to remain at home? We need qualitative research to explore the informal-formal care networks of the very old.
Longitudinal associations between falls and future risk of cognitive decline, the Motoric Cognitive Risk syndrome and dementia: the Einstein Ageing Study
Authors: Jayakody Oshadi , Blumen Helena M , Breslin Monique , Ayers Emmeline , Lipton Richard B , Verghese Joe , Callisaya Michele L
Published: February 2022

Background

falls share risk factors with cognitive decline but whether falls predict cognitive decline, pre-dementia syndromes and dementia is poorly understood.

Objectives

this study aimed to examine if falls are associated with cognitive decline in specific domains and the risk of Motoric Cognitive Risk (MCR) syndrome and dementia.

Design

cross-sectional study.

Methods

in older people (age 80.6 ± 5.3 years) free of dementia at baseline, the number of falls (none, one or multiple) during the year before enrolment and the first year of follow-up (exposure) were recorded. Decline in specific cognitive functions (global cognition, episodic verbal memory, verbal fluency, working memory, response inhibition and processing speed-attention), incident MCR and incident dementia were outcome measures. Linear mixed effects models were used to examine the associations between falls and cognitive decline, adjusting for confounders. Cox proportional hazards models were used to determine if falls predicted risk of incident MCR or dementia.

Results

of 522 eligible participants, 140 had a single fall and 70 had multiple falls. Multiple falls were associated with a greater decline in global cognition, episodic memory, verbal fluency and processing speed-attention compared to those with no falls (P < 0.05). Over a median follow-up of 1.0 years 36 participants developed MCR and 43 participants developed dementia. Those with multiple falls had a two-fold increased risk of MCR compared to those with no falls, but no increased risk of developing dementia.

Conclusions

multiple falls may be an important marker to identify older people at greater risk of future cognitive decline and incident MCR.
Assessment as a Site of Anti/Oppressive Social Work Practice: Negotiating with Power and the De/Professionalisation of Social Work
Authors: Lee Eunjung
Published: February 2022

Social work practice starts with an effort to understand clients-in-context, a task which involves a process of assessment. Whilst social workers often assess clients-in-systems, rarely do they consider the social worker-in-systems as part of the client’s context. Guided by Foucault’s concepts of disciplinary and biopolitical power and related constructs of ‘Panopticism’ and ‘homo oeconomicus’, this article interrogates how the social worker’s observational gaze in assessment has become veiled in practice. Using a critical review method, the author examines how Foucault’s notion of a ‘faceless gaze’ has been increasingly intensified by the use of information technology in ‘common assessment’, thereby transforming the fundamentals of assessment from understanding the client for ‘care’ to ‘managing risk’ in neoliberal governance. This article historicises and politicises temporal discourses of social work assessment and illustrates how the worker’s embodied knowledge of assessment as a governing apparatus may solidify and/or endanger the social work profession. Locating assessment as a site of social in/justice, this critical review on the inevitable workings of power in assessment invites social workers to re-think the boundaries of de/professionalisation and to critically reflect on and re-imagine everyday institutional practices in social work assessment.
Cholinergic and hippocampal systems facilitate cross-domain cognitive recovery after stroke
Authors: O’Sullivan Michael J. , Oestreich Lena K. L. , Wright Paul , Clarkson Andrew N.
Published: February 2022

Spontaneous recovery of motor and cognitive function occurs in many individuals after stroke. The mechanisms are incompletely understood, but may involve neurotransmitter systems that support neural plasticity, networks that are involved in learning and regions of the brain that are able to flexibly adapt to demand (such as the ‘multiple-demand system').

Forty-two patients with first symptomatic ischaemic stroke were enrolled in a longitudinal cohort study of cognitive function after stroke. High-resolution volumetric, diffusion MRI and neuropsychological assessment were performed at a mean of 70 ± 18 days after stroke. Cognitive assessment was repeated 1 year after stroke, using parallel test versions to avoid learning effects, and change scores were computed for long-term episodic, short-term and working memory. Structural MRI features that predicted change in cognitive scores were identified by a two-stage analysis: a discovery phase used whole-brain approaches in a hypothesis-free unbiased way; and an independent focused phase, where measurements were derived from regions identified in the discovery phase, using targeted volumetric measurements or tractography. Evaluation of the cholinergic basal forebrain, based on a validated atlas-based approach, was included given prior evidence of a role in neural plasticity.

The status of the fornix, cholinergic basal forebrain and a set of hippocampal subfields were found to predict improvement in long-term memory performance. In contrast to prior expectation, the same pattern was found for short-term and working memory, suggesting that these regions are part of a common infrastructure that supports recovery across cognitive domains. Associations between cholinergic basal forebrain volume and cognitive recovery were found primarily in subregions associated with the nucleus basalis of Meynert, suggesting that it is the cholinergic outflow to the neocortex that enables recovery. Support vector regression models derived from baseline measurements of fornix, cholinergic basal forebrain and hippocampal subfields were able to explain 62% of change in long-term episodic and 41% of change in working memory performance over the subsequent 9 months.

The results suggest that the cholinergic system and extended hippocampal network play key roles in cognitive recovery after stroke. Evaluation of these systems early after stroke may inform personalized therapeutic strategies to enhance recovery.
Clinical features and nasal inflammation in asthma and allergic rhinitis
Authors: Chen Meiping , Ge Yijun , Lin Wanmi , Ying Haiping , Zhang Wen , Yu Xuechan , Li Chunlin , Cao Chao
Published: February 2022

Asthma and allergic rhinitis (AR) are widely considered to be the most common chronic inflammatory disorders. This study was performed to investigate the clinical features, disease severity, and upper airway inflammation among patients with asthma, AR, and asthma comorbid AR. Blood and nasal lavage fluid samples were collected from patients with isolated asthma (n = 23), isolated AR (n = 22), and asthma comorbid AR (n = 22). Demographic data, symptom evaluation, and spirometry were obtained from all subjects. The levels of interleukin (IL)-4, IL-5, IL-13, IL-17, IL-25, IL-33, and S100 proteins were measured in the nasal lavage fluid. Compared with isolated asthma, patients with asthma comorbid AR showed a lower quality of life according to the asthma quality-of-life questionnaire (AQLQ) score (6.11 ± 0.47 vs. 6.45 ± 0.35, P = 0.007). Additionally, no significant difference in the levels of IL-4 (P = 0.116), IL-25 (P = 0.235), and S100A12 (P = 0.392) was observed in nasal lavage fluid among three groups. However, miniscule levels of IL-5, IL-17, IL-13, IL-33, S100A8, and S100A9 were detected in nasal lavage fluid in all three groups. Patients with asthma comorbid AR showed an increased level of systemic cytokine in plasma than that of patients with isolated AR or asthma alone. The finding from our study may help clinicians to better understand the airway inflammation among asthma patients with or without AR.
Voxel-based morphometry and a deep learning model for the diagnosis of early Alzheimer’s disease based on cerebral gray matter changes
Authors: Huang Huaidong , Zheng Shiqiang , Yang Zhongxian , Wu Yi , Li Yan , Qiu Jinming , Cheng Yan , Lin Panpan , Lin Yan , Guan Jitian , Mikulis David John , Zhou Teng , Wu Renhua
Published: February 2022

This study aimed to analyse cerebral grey matter changes in mild cognitive impairment (MCI) using voxel-based morphometry and to diagnose early Alzheimer's disease using deep learning methods based on convolutional neural networks (CNNs) evaluating these changes. Participants (111 MCI, 73 normal cognition) underwent 3-T structural magnetic resonance imaging. The obtained images were assessed using voxel-based morphometry, including extraction of cerebral grey matter, analyses of statistical differences, and correlation analyses between cerebral grey matter and clinical cognitive scores in MCI. The CNN-based deep learning method was used to extract features of cerebral grey matter images. Compared to subjects with normal cognition, participants with MCI had grey matter atrophy mainly in the entorhinal cortex, frontal cortex, and bilateral frontotemporal lobes (p < 0.0001). This atrophy was significantly correlated with the decline in cognitive scores (p < 0.01). The accuracy, sensitivity, and specificity of the CNN model for identifying participants with MCI were 80.9%, 88.9%, and 75%, respectively. The area under the curve of the model was 0.891. These findings demonstrate that research based on brain morphology can provide an effective way for the clinical, non-invasive, objective evaluation and identification of early Alzheimer's disease.