Surface deformations and gravity changes caused by pressurized finite ellipsoidal cavities

We develop quasi-analytical solutions for the surface deformation field and gravity changes due to the pressurization of a finite (triaxial) ellipsoidal cavity in a half-space. The solution is in the form of a non-uniform distribution of triaxial point sources within the cavity. The point sources have the same aspect ratio, determined by the cavity shape, while their strengths and spacing are determined in an adaptive manner, such that the net point-source potency per unit volume is uniform. We validate and compare our solution with analytical and numerical solutions. We provide computationally efficient MATLAB codes tailored for source inversions. This solution opens the possibility of exploring the geometry of shallow magma chambers for potential deviations from axial symmetry

Dike intrusions during rifting episodes obey scaling relationships similar to earthquakes

As continental rifts evolve towards mid-ocean ridges, strain is accommodated by repeated episodes of faulting and magmatism. Discrete rifting episodes have been observed along two subaerial divergent plate boundaries, the Krafla segment of the Northern Volcanic Rift Zone in Iceland and the Manda-Hararo segment of the Red Sea Rift in Ethiopia. In both cases, the initial and largest dike intrusion was followed by a series of smaller intrusions. By performing a statistical analysis of these rifting episodes, we demonstrate that dike intrusions obey scaling relationships similar to earthquakes. We find that the dimensions of dike intrusions obey a power law analogous to the Gutenberg-Richter relation and the long-term release of geodetic moment is governed by a relationship consistent with the Omori law. Due to the effects of magma supply, the timing of secondary dike intrusions differs from that of the aftershocks. This work provides evidence of self-similarity in the rifting process

Editorial: Structural and Dynamic Aspects of Protein Function and Allostery

Editorial on the Research Topi

Il polimorfismo del paracetamolo: indagine mediante spettroscopia Raman e metodi computazionali

Lo studio del polimorfismo gioca un ruolo fondamentale in diversi ambiti di ricerca, con applicazioni importanti nel campo dei semi conduttori organici e dei farmaci, dovuto al fatto che i diversi polimorfi di una sostanza presentano proprietà chimico-fisiche distinte. Questo lavoro di tesi si è focalizzato sullo studio del polimorfismo del paracetamolo, principio attivo (API) di diversi farmaci molto utilizzati, attraverso l’utilizzo della microscopia Raman. La microscopia Raman è una tecnica efficace per l’indagine del polimorfismo di materiali organici ed inorganici, in quanto permette di monitorare la presenza di diverse fasi solide e le loro trasformazioni su scala micrometrica. Le differenze di struttura cristallina che caratterizzano i polimorfi vengono analizzate attraverso gli spettri Raman nella regione dei modi reticolari (10-150 cm^{-1}), le cui frequenze sondano le interazioni inter-molecolari, molto sensibili anche a lievi differenze di impaccamento molecolare. Con questa tecnica abbiamo caratterizzato le forme I, II, III (quella elusiva) e diverse miscele di fase di paracetamolo su campioni ottenuti con numerose tecniche di crescita dei cristalli. Per questa tesi è stato svolto anche uno studio computazionale, attraverso metodi Density Functional Theory (DFT) per la molecola isolata e metodi di minimizzazione dell’energia e di dinamica reticolare per i sistemi cristallini. Abbiamo inoltre verificato se il modello di potenziale di letteratura scelto (Dreiding [Mayo1990]) fosse adatto per descrivere la molecola di paracetamolo, le strutture dei suoi polimorfi e i relativi spettri vibrazionali

Explosive expansion of a slowly decompressed magma analogue: Evidence for delayed bubble nucleation

While ascending in the plumbing system of volcanoes, magma undergoes decompression at rates spanning several orders of magnitude and set by a number of factors internal and external to the volcano. Slow decompression generally results in an effusive or mildly explosive expansion of the magma, but counterexamples of sudden switches from effusive to explosive eruptive behavior have been documented at various volcanoes worldwide. The mechanisms involved in this behavior are currently debated, in particular for basaltic magmas. Here, we explore the interplay between decompression rate and vesiculation vigor by decompressing a magma analogue obtained by dissolving pine resin into acetone in varying proportions. Analogue experiments allow direct observations of the processes of bubble nucleation and growth, flow dynamics, and fragmentation that is not currently possible with magmatic systems. Our mixtures contain solid particles, and upon decompression, nucleation of acetone bubbles is observed. We find that mixtures with a high acetone content, containing smaller and fewer solid particles, experience strong supersaturation and fragment under very slow decompressions, despite having low viscosity, while mixtures with lower acetone content, with more and larger solid particles, degas efficiently without fragmentation. We interpret our results in terms of delayed bubble nucleation due to a lack of efficient nucleation sites. We discuss how a similar mechanism might induce violent, explosive expansion in volatile‐rich and poorly crystalline low‐silica magmas, by analogy with the behavior of rhyolitic magmas

Rancang Bangun Dan Analisis Usability Website Badan Usaha Penerbit Kampus

Introducing a product certainly requires a medium or intermediary so that the product can be known by the wider community. One of the most frequently used media nowadays is the website or marketing site. The main purpose of this website is to promote products that have been made based on the works of the authors to be better known to the wider community. A website must also be user-friendly, easy to understand, access, remember, and provide useful information to its users. The creation of this website uses the Web Development Life Cycle (WDLC) method, the website will be tested using the usability model which is a qualitative analysis to determine how easy the user is using the interface of an application. The data collection techniques will use the interview technique, with the determination of the sample with purposive sampling technique. The Data obtained later will be analyzed and tested validity with techniques found in qualitative research methods.Memperkenalkan suatu produk tentunya memerlukan sebuah media atau perantara agar produk tersebut dapat diketahui oleh masyarakat luas. Salah satu media yang paling sering digunakan saat ini adalah website atau situs pemasaran. Tujuan utama dari website ini adalah untuk mempromosikan produk-produk yang telah dibuat berdasarkan karya dari penulis agar lebih dikenal masyarakat luas. Sebuah website juga harus dapat sesuai dengan penggunanya, mudah dipahami, diakses, diingat, dan memberikan informasi yang bermanfaat bagi penggunanya. Pembuatan website ini menggunakan metode Web Development Life Cycle (WDLC), nantinya website tersebut akan diuji menggunakan model usability yang merupakan analisis kualitatif untuk menentukan seberapa mudah user menggunakan antarmuka sebuah aplikasi. Teknik pengumpulan data akan menggunakan teknik wawancara, dengan penentuan sampel dengan teknik purposive sampling. Data yang diperoleh nantinya akan di analisis dan diuji validitasnya dengan teknik yang terdapat pada metode penelitian kualitati

Eigenvector Centrality Distribution for Characterization of Protein Allosteric Pathways

Determining the principal energy pathways for allosteric communication in biomolecules, that occur as a result of thermal motion, remains challenging due to the intrinsic complexity of the systems involved. Graph theory provides an approach for making sense of such complexity, where allosteric proteins can be represented as networks of amino acids. In this work, we establish the eigenvector centrality metric in terms of the mutual information, as a mean of elucidating the allosteric mechanism that regulates the enzymatic activity of proteins. Moreover, we propose a strategy to characterize the range of the physical interactions that underlie the allosteric process. In particular, the well known enzyme, imidazol glycerol phosphate synthase (IGPS), is utilized to test the proposed methodology. The eigenvector centrality measurement successfully describes the allosteric pathways of IGPS, and allows to pinpoint key amino acids in terms of their relevance in the momentum transfer process. The resulting insight can be utilized for refining the control of IGPS activity, widening the scope for its engineering. Furthermore, we propose a new centrality metric quantifying the relevance of the surroundings of each residue. In addition, the proposed technique is validated against experimental solution NMR measurements yielding fully consistent results. Overall, the methodologies proposed in the present work constitute a powerful and cost effective strategy to gain insight on the allosteric mechanism of proteins

Explosive expansion of a slowly-decompressed magma analog:evidence of delayed bubble nucleation

While ascending in the plumbing system of volcanoes, magma undergoes decompression at rates spanning several orders of magnitude and set by a number of factors internal and external to the volcano. Slow decompression generally results in an effusive or mildly explosive expansion of the magma, but counterexamples of sudden switches from effusive to explosive eruptive behaviour have been documented at various volcanoes worldwide. The mechanisms involved in this behavior are currently debated, in particular regarding basaltic magmas. Here, we explore the interplay between decompression rate and vesiculation vigour by decompressing a magma analog obtained by dissolving pine resin into acetone in varying proportions. Our mixtures contain solid particles and upon decompression experience the nucleation of acetone bubbles. We find mixtures high in acetone, containing smaller and fewer solid particles, experience strong supersaturation and fragment for very slow decompressions, despite having low viscosity, while mixtures low in acetone, with more and larger solid particles degas efficiently. We interpret our results in terms of delayed bubble nucleation due to a lack of efficient nucleation sites. We discuss how a similar mechanism might induce violent, explosive expansion in volatile-rich and poorly crystalline low-silica magmas, by analogy to previous inferences for rhyolitic magmas

Perlindungan Hukum Terhadap Anak Korban Perkosaan di Indonesia

Perhatian terhadap anak korban perkosaan perlu diberikan secara serius oleh semua pihak mengingat mereka merupakan aset berharga bagi bangsa. Korban yang dalam hal ini anak berhak memperoleh pemenuhan atas hak-haknya yang telah dijamin oleh hukum serta diperlakukan secara tidak diskriminatif. Namun, pada kenyataannya anak sebagai korban dari perkosaan masih banyak yang kurang memperoleh pemenuhan atas hak-haknya tersebut. Maksud dari penulis mengadakan penelitian ini tujuannya yang pertama yaitu untuk mengetahui bentuk-bentuk perlindungan seperti apa saja yang diberikan terhadap anak sebagai akibat dari perkosaan yang dialaminya, dan yang kedua adalah untuk mengetahui tentang kendala apa saja yang ada sehingga mengakibatkan anak sebagai korban dari perkosaan ini kurang dapat memperoleh hak-haknya meskipun telah dijamin oleh hukum. Penulis pada skripsi ini memakai penelitian yuridis normatif (legal research) dengan perundang-undangan sebagai pendekatannya. Adapun bahan yang digunakan terdiri dari bahan hukum primer yang berupa perundangundangan dan juga buku serta jurnal sebagai bahan hukum sekundernya. Setelah dilakukannya penelitian, maka diperoleh jawaban oleh penulis atas persoalan yang diteliti yaitu : (1) Pada prinsipnya, perlindungan hukum sendiri terbagi ke dalam dua jenis jika dilihat dari sifatnya, yaitu berupa preventif dan juga repsresif. Adanya perlindungan yang bertujuan untuk mencegah terjadinya konflik atau sifatnya adalah preventif, dapat dilihat dari diterapkannya hukuman terhadap pelaku perkosaan, di mana dapat dikenai yaitu 15 (lima belas) tahun maksimal pidana berupa penjara serta membayar maksimal yaitu Rp. 5.000.000.000,00 (lima miliar rupiah) sebagai denda seperti yang telah diatur didalam Pasal 81 UUPA. Sedangkan yang bersifat represif atau perlindungan hukum yang diberikan setelah terjadinya konflik wujud perlindungannya antara lain berupa : mendapatkan tindakan yang segera berkaitan dengan pengobatan maupun rehabilitasi atas dirinya, baik dari segi fisik, psikis, serta sosial, termasuk juga tindakan untuk mencegah timbulnya penyakit maupun hal lain yang dapat mengganggu kesehatannya; diberikan suatu bantuan sosial kepada anak yang keluarganya memang tergolong kurang berada; serta didampingi dalam semua tahapan peradilan. (2) Meskipun dapat dikatakan bahwa pengaturan mengenai perlindungan terhadap anak dapat dikatakan sudah jauh lebih baik, namun sampai saat ini belum semua yang menjadi hak anak sebagai korban dari perkosaan tersebut dapat diberikan secara maksimal. Terdapat berbagai kendala yang masih sering ditemui dalam upaya pemberian perlindungan seperti korban masih ada yang tidak melaporkan kejadian yang dialami, korban sulit untuk diminta menceritakan kembali kejadian yang telah menimpanya, tidak adanya orang yang melihat saat perkosaan terjadi, masih terbatasnya terkait dengan keberadaan penyidik yang diperuntukkan memang bagi anak, serta keterbatasan fasilitas penunjang memadai

Effect of Scanning Strategy in the L-PBF Process of 18Ni300 Maraging Steel

Maraging steels are good candidates for the laser powder bed fusion process (L-PBF), also known as Selective Laser Melting, due to excellent weldability and resistance to quench cracking. Powders physical and chemical characteristics dominate the final microstructure and properties of the printed parts, that are also heavily influenced by the process parameters. In this study, the effects of the scanning strategies on dimensions, average surface roughness, density and material hardness were evaluated, keeping the powder type and the volumetric energy density (Andrew number) constant. The effects of the scanning strategy on these properties are far less understood than on other important ones, like residual stresses and distortion, strongly affected by the scanning strategy. In this study, parallel stripes, chessboard and hexagonal pattern strategies were studied, keeping the Andrew number constant but varying the interlayer rotation. In general, the hexagonal strategy underperformed compared to the chessboard and the stripes ones