RANCANG BANGUN ALAT BANTU PEMOTONG PLAT DENGAN GERINDA (PROSES PENGUJIAN)

Laporan akhir yang berjudul “Rancang Bangun Alat Bantu Pemotong Plat Dengan Gerinda (Perawatan dan Perbaikan)”, bertujuanuntuk memotong plat secara efisien dan presisi. Pada pemotongan bisa menggunakan, gerinda, gunting pelat , lasan Untuk memotong benda agar berbentuk persegi atau parsegi panjang harus presisi merupakan hal yang sulit untuk dilakukan. Pada pemotonganplatjuga akan sulit jika menggunakan gergaji ataupun dengan pemotongan mengunakan pengelasan karena plat tipis dan akan. Jika menggunakan gergaji kelemahannya biaya yang dikeluarkan lebih besar, hasilnya kurang presisi. Pada pemotongan plat yang berbentuk persegi atau persegi panjanga digunakan pemotongan dengan dua cara vertical dan horizontal hasilnya presisi namun pada proses pemotongannya harus memutar dudukan dari alat tersebut. Oleh karena itu untuk memudahkan dalam memproduksi suatu produksecara massal maka alat yang digunakan akan dimodifikasi agar proses pembuatan benda menjadi lebih efisiensi dan lebih mudah mendapatkan kualitas produk yang bermutu serta laju produksi yang banyak

Pemanfaatan Daun Kersen (Muntingia calabura L.) dalam Penanganan Diabetes Mellitus

Diabetes mellitus (DM) or better known as diabetes, is one of the diseases caused by high blood sugar accompanied by disorders of carbohydrate, fat, and protein metabolism as a result of insufficient insulin function. a study by Hendra Stevani, et al in 2016 concerning the effectiveness of the Decoction of Kersen Leaves (Muntingia calabura L.) on Reducing Blood Glucose Levels in Mice (Mus musculus). Cherry leaves are proven to reduce blood sugar levels conducted in animal experiments in the form of mice, with a concentration of 15%Diabetes Melitus (DM) atau yang lebih di kenal dengan sebutan kencing manis, merupakan salah satu penyakit yang disebabkan tingginya gula darah disertai dengan gangguan metabolisme karbohidrat, lemak, dan protein sebagai akibat ketidakcukupan fungsi insulin. penelitian dari Hendra Stevani, dkk tahun 2016 mengenai efektifitas Rebusan Daun Kersen (Muntingia calabura L.) Terhadap Penurunan Kadar Glukosa Darah Pada Mencit (Mus musculus). Daun kersen terbukti dapat menurunkan kadar gula darah yang dilakukan pada hewan percobaan berupa mencit, dengan konsentrasi 15

One-dimensional collision carts computer model and its design ideas for productive experiential learning

We develop an Easy Java Simulation (EJS) model for students to experience the physics of idealized one-dimensional collision carts. The physics model is described and simulated by both continuous dynamics and discrete transition during collision. In the field of designing computer simulations, we discuss briefly three pedagogical considerations such as 1) consistent simulation world view with pen paper representation, 2) data table, scientific graphs and symbolic mathematical representations for ease of data collection and multiple representational visualizations and 3) game for simple concept testing that can further support learning. We also suggest using physical world setup to be augmented complimentary with simulation while highlighting three advantages of real collision carts equipment like tacit 3D experience, random errors in measurement and conceptual significance of conservation of momentum applied to just before and after collision. General feedback from the students has been relatively positive, and we hope teachers will find the simulation useful in their own classes. 2015 Resources added: http://iwant2study.org/ospsg/index.php/interactive-resources/physics/02-newtonian-mechanics/02-dynamics/46-one-dimension-collision-js-model http://iwant2study.org/ospsg/index.php/interactive-resources/physics/02-newtonian-mechanics/02-dynamics/195-elastic-collisionComment: 6 pages, 8 figures, 1 table, 1 L. K. Wee, Physics Education 47 (3), 301 (2012); ISSN 0031-912

Decay properties of 22Ne+α^{22}\mathrm{Ne} + \alpha resonances and their impact on ss-process nucleosynthesis

The astrophysical $s$-process is one of the two main processes forming elements heavier than iron. A key outstanding uncertainty surrounding $s$-process nucleosynthesis is the neutron flux generated by the ${}^{22}\mathrm{Ne}(\alpha, n){}^{25}\mathrm{Mg}$ reaction during the He-core and C-shell burning phases of massive stars. This reaction, as well as the competing ${}^{22}\mathrm{Ne}(\alpha, \gamma){}^{26}\mathrm{Mg}$ reaction, is not well constrained in the important temperature regime from ${\sim} 0.2$--$0.4$~GK, owing to uncertainties in the nuclear properties of resonances lying within the Gamow window. To address these uncertainties, we have performed a new measurement of the ${}^{22}\mathrm{Ne}({}^{6}\mathrm{Li}, d){}^{26}\mathrm{Mg}$ reaction in inverse kinematics, detecting the outgoing deuterons and ${}^{25,26}\mathrm{Mg}$ recoils in coincidence. We have established a new $n / \gamma$ decay branching ratio of $1.14(26)$ for the key $E_x = 11.32$ MeV resonance in $^{26}\mathrm{Mg}$, which results in a new $(\alpha, n)$ strength for this resonance of $42(11)~\mu$eV when combined with the well-established $(\alpha, \gamma)$ strength of this resonance. We have also determined new upper limits on the $\alpha$ partial widths of neutron-unbound resonances at $E_x = 11.112,$ $11.163$, $11.169$, and $11.171$ MeV. Monte-Carlo calculations of the stellar ${}^{22}\mathrm{Ne}(\alpha, n){}^{25}\mathrm{Mg}$ and ${}^{22}\mathrm{Ne}(\alpha, \gamma){}^{26}\mathrm{Mg}$ rates, which incorporate these results, indicate that both rates are substantially lower than previously thought in the temperature range from ${\sim} 0.2$--$0.4$~GK.Comment: 17 pages, 4 figures, accepted for publication in Phys. Lett.

Single-cell transcriptomic atlas-guided development of CAR-T cells for the treatment of acute myeloid leukemia

A single-cell screening approach identifies targets for CAR-T cells in acute myeloid leukemia. Chimeric antigen receptor T cells (CAR-T cells) have emerged as a powerful treatment option for individuals with B cell malignancies but have yet to achieve success in treating acute myeloid leukemia (AML) due to a lack of safe targets. Here we leveraged an atlas of publicly available RNA-sequencing data of over 500,000 single cells from 15 individuals with AML and tissue from 9 healthy individuals for prediction of target antigens that are expressed on malignant cells but lacking on healthy cells, including T cells. Aided by this high-resolution, single-cell expression approach, we computationally identify colony-stimulating factor 1 receptor and cluster of differentiation 86 as targets for CAR-T cell therapy in AML. Functional validation of these established CAR-T cells shows robust in vitro and in vivo efficacy in cell line- and human-derived AML models with minimal off-target toxicity toward relevant healthy human tissues. This provides a strong rationale for further clinical development

A Multiscale Poromechanics Model Integrating Myocardial Perfusion and the Epicardial Coronary Vessels

The importance of myocardial perfusion at the outset of cardiac disease remains largely understudied. To address this topic we present a mathematical model that considers the systemic circulation, the coronary vessels, the myocardium, and the interactions among these components. The core of the whole model is the description of the myocardium as a multicompartment poromechanics system. A novel decomposition of the poroelastic Helmholtz potential involved in the poromechanics model allows for a quasi-incompressible model that adequately describes the physical interaction among all components in the porous medium. We further provide a rigorous mathematical analysis that gives guidelines for the choice of the Helmholtz potential. To reduce the computational cost of our integrated model we propose decoupling the deformation of the tissue and systemic circulation from the porous flow in the myocardium and coronary vessels, which allows us to apply the model also in combination with precomputed cardiac displacements, obtained form other models or medical imaging data. We test the methodology through the simulation of a heartbeat in healthy conditions that replicates the systolic impediment phenomenon, which is particularly challenging to capture as it arises from the interaction of several parts of the model

3D–0D closed-loop model for the simulation of cardiac biventricular electromechanics

Two crucial factors for accurate numerical simulations of cardiac electromechanics, which are also essential to reproduce the synchronous activity of the heart, are: i) accounting for the interaction between the heart and the circulatory system that determines pressures and volumes loads in the heart chambers; ii) reconstructing the muscular fiber architecture that drives the electrophysiology signal and the myocardium contraction. In this work, we present a 3D biventricular electromechanical model coupled with a 0D closed-loop model of the whole cardiovascular system that addresses the two former crucial factors. With this aim, we introduce a boundary condition for the mechanical problem that accounts for the neglected part of the domain located on top of the biventricular basal plane and that is consistent with the principles of momentum and energy conservation. We also discuss in detail the coupling conditions that stand behind the 3D and the 0D models. We perform electromechanical simulations in physiological conditions using the 3D-0D model and we show that our results match the experimental data of relevant mechanical biomarkers available in literature. Furthermore, we investigate different arrangements in cross-fibers active contraction. We prove that an active tension along the sheet direction counteracts the myofiber contraction, while the one along the sheet-normal direction enhances the cardiac work. Finally, several myofiber architectures are analysed. We show that a different fiber field in the septal area and in the transmural wall effect the pumping functionality of the left ventricle

Partitioned and Monolithic Algorithms for the Numerical Solution of Cardiac Fluid-Structure Interaction

We review and compare different fluid-structure interaction (FSI) numerical methods in the context of heart modeling, aiming at assessing their computational efficiency for cardiac numerical simulations and selecting the most appropriate method for heart FSI. Blood dynamics within the human heart is characterized by active muscular action, during both contraction and relaxation phases of the heartbeat. The efficient solution of the FSI problem in this context is challenging, due to the added-mass effect (caused by the comparable densities of fluid and solid, typical of biomechanics) and to the complexity, nonlinearity and anisotropy of cardiac constitutive laws. In this work, we review existing numerical coupling schemes for FSI in the two classes of strongly-coupled partitioned and monolithic schemes. The schemes are compared on numerical tests that mimic the flow regime characterizing the heartbeat in a human ventricle, during both systole and diastole. Active mechanics is treated in both the active stress and active strain frameworks. Computational costs suggest the use of a monolithic method. We employ it to simulate a full heartbeat of a human ventricle, showing how it allows to efficiently obtain physiologically meaningful results

A comprehensive mathematical model for cardiac perfusion

Abstract The aim of this paper is to introduce a new mathematical model that simulates myocardial blood perfusion that accounts for multiscale and multiphysics features. Our model incorporates cardiac electrophysiology, active and passive mechanics, hemodynamics, valve modeling, and a multicompartment Darcy model of perfusion. We consider a fully coupled electromechanical model of the left heart that provides input for a fully coupled Navier–Stokes–Darcy model for myocardial perfusion. The fluid dynamics problem is modeled in a left heart geometry that includes large epicardial coronaries, while the multicompartment Darcy model is set in a biventricular myocardium. Using a realistic and detailed cardiac geometry, our simulations demonstrate the biophysical fidelity of our model in describing cardiac perfusion. Specifically, we successfully validate the model reliability by comparing in-silico coronary flow rates and average myocardial blood flow with clinically established values ranges reported in relevant literature. Additionally, we investigate the impact of a regurgitant aortic valve on myocardial perfusion, and our results indicate a reduction in myocardial perfusion due to blood flow taken away by the left ventricle during diastole. To the best of our knowledge, our work represents the first instance where electromechanics, hemodynamics, and perfusion are integrated into a single computational framework