PENGARUH KONSENTRASI DEKSTRIN DAN pH TERHADAP KARAKTERISTIK SERBUK PEWARNA HIJAU ALAMI DARI DAUN KATUK (Sauropus androgynous L. Merr) DENGAN METODE FOAM-MAT DRYING

This study aimed to determine the interaction between dextrin concentration and pH on the characteristics of a natural green dye powder from leaves of katuk foam-mat drying method. The experimental design used was a randomized block design (RAK) with a 3x3 factorial design with repetition as much as 3 times. The factors used is dextrin concentration (D) of 3 levels (d1 = 10%, d2 = 12.5%, 15%) and pH (P) (p1 = 7, p2 = 8, p3 = 9). The response in this study is the water content (%), chlorophyll content (%), organoleptic color and flavor. Best formulations in the preliminary study is a comparison katuk leaves and water is 1: 1. The products chosen on primary research by chemical response moisture content and chlorophyll content, and according to the response organoleptic based on attributes of color and flavor is a powder dye natural green of the leaf katuk with treatment d1p1 (d1 dextrin concentration of 10%, p1 pH 7). Keywords : Natural Dyes, Leaf Katuk, and Chlorophyll

Impact of Shared Control Modalities on Performance and Usability of Semi-autonomous Prostheses

Semi-autonomous (SA) control of upper-limb prostheses can improve the performance and decrease the cognitive burden of a user. In this approach, a prosthesis is equipped with additional sensors (e.g., computer vision) that provide contextual information and enable the system to accomplish some tasks automatically. Autonomous control is fused with a volitional input of a user to compute the commands that are sent to the prosthesis. Although several promising prototypes demonstrating the potential of this approach have been presented, methods to integrate the two control streams (i.e., autonomous and volitional) have not been systematically investigated. In the present study, we implemented three shared control modalities (i.e., sequential, simultaneous, and continuous) and compared their performance, as well as the cognitive and physical burdens imposed on the user. In the sequential approach, the volitional input disabled the autonomous control. In the simultaneous approach, the volitional input to a specific degree of freedom (DoF) activated autonomous control of other DoFs, whereas in the continuous approach, autonomous control was always active except for the DoFs controlled by the user. The experiment was conducted in ten able-bodied subjects, and these subjects used an SA prosthesis to perform reach-and-grasp tasks while reacting to audio cues (dual tasking). The results demonstrated that, compared to the manual baseline (volitional control only), all three SA modalities accomplished the task in a shorter time and resulted in less volitional control input. The simultaneous SA modality performed worse than the sequential and continuous SA approaches. When systematic errors were introduced in the autonomous controller to generate a mismatch between the goals of the user and controller, the performance of SA modalities substantially decreased, even below the manual baseline. The sequential SA scheme was the least impacted one in terms of errors. The present study demonstrates that a specific approach for integrating volitional and autonomous control is indeed an important factor that significantly affects the performance and physical and cognitive load, and therefore these should be considered when designing SA prostheses

A compact system for simultaneous stimulation and recording for closed-loop myoelectric control

Background.Despite important advancements in control and mechatronics of myoelectric prostheses, the communication between the user and his/her bionic limb is still unidirectional, as these systems do not provide somatosensory feedback. Electrotactile stimulation is an attractive technology to close the control loop since it allows flexible modulation of multiple parameters and compact interface design via multi-pad electrodes. However, the stimulation interferes with the recording of myoelectric signals and this can be detrimental to control.The work in this study was supported by the project ROBIN (8022-00243A and 8022-00226B) funded by the Independent Research Fund Denmark

KAJIAN PENGARUH JENIS DAN KONSENTRASI TEPUNG DIMODIFIKASI AUTOCLAVING-COOLING CYCLE TERHADAP KARAKTERISTIK BROWNIES UBI JALAR UNGU (NON-GANDUM)

Ketergantungan masyarakat terhadap konsumsi gandum masih sangat tinggi. Padahal, negara Indonesia mempunyai kekayaan alam yang melimpah terutama pada jenis tanaman pangan lokal umbi-umbian. Konsumsi umbi-umbian tidak hanya dapat mengatasi permasalahan impor terigu, tetapi juga dapat memenuhi kebutuhan zat gizi masyarakat dan memiliki nilai fungsional yang bermanfaat untuk menjaga kesehatan. Khususnya serat pangan dan antioksidan. Tingkat pemanfaatan modifikasi Autoclaving-Cooling Cycle pun sangat rendah, padahal modifikasi ini memberikan keuntungan dapat meningkatkan kadar pati resisten dan menurunkan daya cerna pati. Tujuan dari penelitian ini adalah untuk mempelajari pengaruh jenis dan konsentrasi tepung dimodifikasi AutoclavingCooling Cycle terhadap brownies ubi jalar ungu. Penelitian yang dilakukan meliputi dua tahap yaitu penelitian pendahuluan yang bertujuan untuk preparasi dan analisis bahan baku. Selanjutnya, tahap kedua mempelajari adanya pengaruh jenis dan konsentrasi tepung dimodifikasi terhadap brownies ubi jalar ungu. Berdasarkan hasil analisis, menggunakan analisis ragam ANOVA (Analysis Of Varian) didapatkan bahwa jenis dan konsentrasi tepung dimodifikasi tidak berpengaruh nyata terhadap warna, overall, kadar air, kekerasan, kelengketan dan kohesivitas brownies ubi jalar ungu. Sedangkan untuk aroma, rasa, dan kadar pati berpengaruh nyata. Penentuan sampel terbaik dilakukan menggunakan metode skoring. Hasil menunjukkan bahwa sampel a2b2 yaitu penambahan tepung ubi jalar dimodifikasi sebanyak 6% memberikan skor tertinggi diantara sampel lainnya. Sampel terbaik memiliki kadar air sebesar 16.21%. kadar abu sebesar 1,28%, kadar protein sebesaar 3,53%, kadar lemak sebesar 29.42%, dan kadar karbohidrat sebesar 49.56%

Growth from birth to 6 months of infants with and without intrauterine preeclampsia exposure

Intrauterine preeclampsia exposure affects the lifelong cardiometabolic health of the child. Our study aimed to compare the growth (from birth to 6 months) of infants exposed to either a normotensive pregnancy or preeclampsia and explore the influence of being born small for gestational age (SGA). Participants were children of women participating in the Post-partum, Physiology, Psychology and Paediatric follow-up cohort study. Birth and 6-month weight and length z-scores were calculated for term and preterm (<37 weeks) babies, and change in weight z-score, rapid weight gain (≥0.67 increase in weight z-score) and conditional weight gain z-score were calculated. Compared with normotensive exposed infants (n = 298), preeclampsia exposed infants (n = 84) were more likely to be born SGA (7% versus 23%; P < 0.001), but weight gain from birth to 6 months, by any measure, did not differ between groups. Infants born SGA, irrespective of pregnancy exposure, were more likely to have rapid weight gain and had greater increases in weight z-score compared with those not born SGA. Preeclampsia exposed infants born SGA may benefit from interventions designed to prevent future cardiometabolic disease

A Novel Method for Vibrotactile Proprioceptive Feedback Using Spatial Encoding and Gaussian Interpolation

Objective: The bidirectional communication between the user and the prosthesis is an important requirement when developing prosthetic hands. Proprioceptive feedback is fundamental to perceiving prosthesis movement without the need for constant visual attention. We propose a novel solution to encode wrist rotation using a vibromotor array and Gaussian interpolation of vibration intensity. The approach generates tactile sensation that smoothly rotates around the forearm congruently with prosthetic wrist rotation. The performance of this scheme was systematically assessed for a range of parameter values (number of motors and Gaussian standard deviation). Methods: Fifteen able-bodied subjects and one individual with congenital limb deficiency used vibrational feedback to control the virtual hand in the target-achievement test. Performance was assessed by end-point error and efficiency as well as subjective impressions. Results: The results showed a preference for smooth feedback and a higher number of motors (8 and 6 versus 4). With 8 and 6 motors, the standard deviation, determining the sensation spread and continuity, could be modulated through a broad range of values (0.1 - 2) without a significant performance loss (error: ∼ 10%; efficiency: ∼ 30%). For low values of standard deviation (0.1-0.5), the number of motors could be reduced to 4 without a significant performance decrease. Conclusion: The study demonstrated that the developed strategy provided meaningful rotation feedback. Moreover, the Gaussian standard deviation can be used as an independent parameter to encode an additional feedback variable. Significance: The proposed method is a flexible and effective approach to providing proprioceptive feedback while adjusting the trade-off between sensation quality and the number of vibromotors

A hierarchical sensorimotor control framework for human-in-the-loop robotic hands.

Human manual dexterity relies critically on touch. Robotic and prosthetic hands are much less dexterous and make little use of the many tactile sensors available. We propose a framework modeled on the hierarchical sensorimotor controllers of the nervous system to link sensing to action in human-in-the-loop, haptically enabled, artificial hands

Radical anti-realism and substructural logics

We first provide the outline of an argument in favour of a radical form of anti-realism premised on the need to comply with two principles, implicitness and immanence, when trying to frame assertability-conditions. It follows from the first principle that one ought to avoid explicit bounding of the length of computations, as is the case for some strict finitists, and look for structural weakening instead. In order to comply with the principle of immanence, one ought to take into account the difference between being able to recognize a proof when presented with one and being able to produce one and thus avoid the idealization of our cognitive capacities that arise within Hilbert-style calculi. We then explore the possibility of weakening structural rules in order to comply with radical anti-realist strictures