Pengembangan Media Video Presentasi pada Mata Kuliah Hidrologi di Universitas Negeri Jakarta

Penelitian ini bertujuan untuk merancang dan mengembangkan media video presentasi yang diterapkan pada mata kuliah Hidrologi. Penelitian ini menerapkan metode Research and Development (R & D) dengan model Borg dan Gall yang dibatasi sampai ujicoba kelompok kecil. Validasi media yang digunakan untuk validasi ahli dengan formula Aiken\u27s V dan untuk penilaian dari mahasiswa menggunakan tes. Hasil validasi menunjukkan bahwa media layak digunakan. Hasil pre-test dan post test yang dianalisis dengan uji t dari 36 mahasiswa diperoleh thitung sebesar 5,052 yang signifikan. Berdasarkan analisis tersebut, dapat disimpulkan bahwa media pembelajaran video presentasi ini layak digunakan dan efektif pada skala terbatas untuk pembelajaran mata kuliah Hidrologi di Pendidikan Teknik Bangunan Universitas Negeri Jakarta

N-(INDAZOLYL)BENZAMIDO DERIVATIVES AS CDK1 INHIBITORS: DESIGN, SYNTHESIS, BIOLOGICAL ACTIVITY, AND MOLECULAR DOCKING STUDIES

A series of N-1H-indazole-1-carboxamides have been synthesized and their effects on both CDK1/cyclin B and K-562 (human chronic myelogenus leukemia) cell line were evaluated. Using a computational model we have observed that all the most active compound 9e,f,i-n exhibited the same binding mode of Purvanalol A in the ATP-binding cleft. Although they were able to moderately inhibit the leukemic cell line K-562, and to show inhibitory activity against the Cdc2-Cyclin B kinase in the low micromolar range, they resulted non cytotoxic against HuDe (IZSL), primary cell cultures from human derm. These preliminary results are quite encouraging in view of the low toxicity showed by the above mentioned compounds

The reshaping of Indian identity in twentieth century North Carolina

According to census reports, the American Indian population has skyrocketed in the United States since the end of World War II. Currently, there are more than two million Native Americans in the country. While some of this growth can be attributed to natural increase and improving health-care, much of the increase comes from changing social conditions. Prior to 1945, many Native Americans, especially those in the South, often tried to hide their identity, primarily because of the negative stereotype associated with being Indian. Over the past half century, however, Indians have become more willing to assert their cultural heritage. The state of North Carolina has the largest Indian population of any state east of the Mississippi River. Over the past fifty years, Native Americans in the state have been struggling to maintain and protect their heritage. In my dissertation, I want to examine the efforts of Native Americans in North Carolina to assert their Indianness since 1945. In other words, what strategies have Tar Heel Indians adopted, conscious or otherwise, to preserve and exhibit their identity

Synthesis and Quantitative Structure–Activity Relationship of Imidazotetrazine Prodrugs with Activity Independent of O6-Methylguanine-DNA-methyltransferase, DNA Mismatch Repair and p53.

The antitumor prodrug Temozolomide is compromised by its dependence for activity on DNA mismatch repair (MMR) and the repair of the chemosensitive DNA lesion, O6-methylguanine (O6-MeG), by O6-methylguanine-DNA-methyltransferase (EC 2.1.1.63, MGMT). Tumor response is also dependent on wild-type p53. Novel 3-(2-anilinoethyl)-substituted imidazotetrazines are reported that have activity independent of MGMT, MMR and p53. This is achieved through a switch of mechanism so that bioactivity derives from imidazotetrazine-generated arylaziridinium ions that principally modify guanine-N7 sites on DNA. Mono- and bi-functional analogs are reported and a quantitative structure-activity relationship (QSAR) study identified the p-tolyl-substituted bi-functional congener as optimized for potency, MGMT-independence and MMR-independence. NCI60 data show the tumor cell response is distinct from other imidazotetrazines and DNA-guanine-N7 active agents such as nitrogen mustards and cisplatin. The new imidazotetrazine compounds are promising agents for further development and their improved in vitro activity validates the principles on which they were designed

Ten Years of Passion:I.S. Gromeka’s Contribution to Science

The work and life of Ippolit Stepanovich Gromeka is reviewed. Gromeka authored a classical set of eleven papers on fluid dynamics in just ten years before a tragic illness ended his life. Sadly, he is not well known to the western scientific community because all his publications were written in Russian. He is one of the three authors who independently derived an analytical solution for accelerating laminar pipe flow. He was the first to eliminate the contradiction between the theories of Young and Laplace on capillary phenomena. He initiated the theoretical basis of helical (Beltrami) flow, and he studied the movement of cyclones and anticyclones seventeen years before Zermelo (whose work is considered as pioneering). He is also the first to analyse wave propagation in liquid-filled hoses, thereby including fluid–structure interaction.</p

What Is a (Pressure) Wavefront?

In the context of two- and three-dimensional wave propagation, the word ‘wavefront’ is used to describe a surface that is expanding in time, and in the corresponding two-dimensional case, it describes a line that is also expanding in time. The equivalent definition in one-dimensional applications is simply a point, but the word ‘wavefront’ is nevertheless commonly used in the context of fluid waves in pipes, albeit for a very different purpose. However, no formal definition exists in the 1D context and the word is not interpreted consistently by all authors, thereby creating a potential for miscommunication that is clearly undesirable in scientific or engineering contexts. This paper uses a wide range of one-dimensional, wave-like phenomena to illustrate how varied wave propagation can be, even when the initial conditions are undisturbed and the trigger of the disturbance is simple. Despite these simplifications, no universally meaningful, formal definition of a wavefront seems to be achievable, partly because, in some instances, key flow parameters such as pressure and velocity exhibit completely different behaviour. Accordingly, instead of seeking a universal, unambiguous definition, a qualitative definition is proposed that is consistent with most of the presented examples and with the most common uses of the word in the general literature.</p

Pengembangan Bahan Ajar Berbasis Modul Elektronik pada Mata Kuliah Hidrolika Prodi Pendidikan Teknik Bangunan Universitas Negeri Jakarta

Penelitian ini mengembangkan bahan ajar berbasis modul elektronik (e-modul) pada mata kuliah Hidrolika di Prodi Pendidikan Teknik Bangunan Universitas Negeri Jakarta. Modul elektronik ini dirancang untuk meningkatkan minat baca dan pemahaman materi mahasiswa. Pengembangan modul elektronik dilatarbelakangi oleh perkembangan teknologi dalam pendidikan, kebutuhan bahan ajar yang sistematis dan menarik, serta kurangnya sumber belajar dan rendahnya motivasi belajar mahasiswa. Penelitian ini menggunakan metode Research and Development (R&amp;D) dengan model pengembangan Four-D (Design, Define, Develop, Disseminate). Penelitian ini menggunakan angket sebagai instrumen pengumpulan data uji kelayakan produk melalui validasi ahli dan uji coba produk kepada mahasiswa PTB UNJ yang telah mengambil mata kuliah Hidrolika. Analisis data validasi ahli dan uji coba produk menggunakan nilai rumus rata-rata. Hasil penelitian berupa modul elektronik yang memuat media pembelajaran menarik seperti video pembelajaran dan tes formatif. Modul elektronik ini telah divalidasi oleh ahli materi dan media, dan mendapatkan hasil yang sangat baik dengan persentase 92% untuk materi dan 82% untuk media. Uji coba terbatas kepada mahasiswa juga menunjukkan respon positif dengan persentase 89%. Pengembangan modul elektronik ini diharapkan dapat membantu mahasiswa dalam memahami mata kuliah Hidrolika dengan lebih baik dan meningkatkan minat belajar mereka. Modul elektronik ini dapat digunakan oleh seluruh mahasiswa Prodi Pendidikan Teknik Bangunan Universitas Negeri Jakarta dan dapat dimasukkan ke dalam Learning Management System (LMS) milik Universitas

Simplified stochastic modelling of the force on a pipe bend due to two-phase slug flow

Slug flow, a flow pattern with alternating aerated liquid pockets (slugs) and large gas bubbles, is a commonly observed flow pattern in oil and gas pipelines. Due to its unsteady character, the force on a pipe bend is fluctuating which results in unacceptable motions when the piping is insufficiently supported. To investigate the risk of fatigue failure of the system, finite-element models are used to predict the dynamic stresses required to estimate the fatigue life of the system. The excitation force of the slug flow is the essential input required for accurate fatigue damage predictions. A new, simplified model of slug forces on a bend is proposed. The model is calculating the slug force by solving the momentum balance over the pipe bend using slug flow properties as liquid holdup and phase velocities. Average properties predicted by a unit slug model cannot predict the stochastic force variations caused by the slug flow. The new approach introduces the stochastic character of slug flow in the force calculations via a log-normal slug length distribution. A Lagrangian slug tracking method is used to solve the governing equations. The modelled liquid holdup, pressure and predicted forces are compared with available measurements and Computational Fluid Dynamics calculations. The measurements were done under atmospheric conditions and the fluids used were air and water. Whether these measurements are representative for high-pressure oil and gas slug flow is unknown. By using a mechanistic approach where the main equations are based on physical laws instead of fitted measured data, the model is applicable for different fluids and operational conditions. To validate the model for oil and gas flows, the results are compared with Computational Fluid Dynamics calculations done with high gas density and typical oil viscosity.</p