Analysing the work required in creating and maintaining a mobile application

When providing a service on the web, there is an ever increasing need for offering a mobile application as one method of usage. Developing a mobile application is expensive, however, as platform specific technologies are required when creating fully native applications, resulting in the need to build and maintain multiple separate code bases for effectively the same application. To solve this issue, different technologies have been created that allow for multiple platforms to be targeted without having to create a separate code base for each one. Cross-platform frameworks allow for a single code base to target multiple mobile platforms, while native runtimes and progressive web application methodologies allow for web technologies to be used in the creation of a mobile application. The goal of this thesis is to evaluate these technologies in terms of work required in creating an application and the quality of the application produced. First, the benefits and drawbacks of each technology are analysed, after which two prototypes, based on the same web application, are built with the most fitting technologies. The prototypes are then compared against each other to see the differences between the technologies in practice. For the case study performed in this thesis, the most promising technologies were cross-platform frameworks and native runtimes. The cross-platform framework React Native and the native runtime Capacitor were chosen to be used in the construction of the prototypes. The results gained from comparing the two frameworks showed that the prototype built with Capacitor was of higher quality than the one built with React Native, while also requiring less development time for its creation

Low-Load Metal-Assisted Catalytic Etching Produces Scalable Porosity in Si Powders

The recently discovered low-load metal-assisted catalytic etching (LL-MACE) creates nanostructured Si with controllable and variable characteristics that distinguish this technique from the conventional high-load variant. LL-MACE employs 150 times less metal catalyst and produces porous Si instead of Si nanowires. In this work, we demonstrate that some of the features of LL-MACE cannot be explained by the present understanding of MACE. With mechanistic insight derived from extensive experimentation, it is demonstrated that (1) the method allows the use of not only Ag, Pd, Pt, and Au as metal catalysts but also Cu and (2) judicious combinations of process parameters such as the type of metal, Si doping levels, and etching temperatures facilitate control over yield (0.065−88%), pore size (3−100 nm), specific surface area (20−310 m2·g−1), and specific pore volume (0.05−1.05 cm3·g−1). The porous structure of the product depends on the space-charge layer, which is controlled by the Si doping and the chemical identity of the deposited metal. The porous structure was also dependent on the dynamic structure of the deposited metal. A distinctive comet-like structure of metal nanoparticles was observed after etching with Cu, Ag, Pd, and, in some cases, Pt; this structure consisted of 10−50 nm main particles surrounded by smaller (\u3c5 nm) nanoparticles. With good scalability and precise control of structural properties, LL-MACE facilitates Si applications in photovoltaics, energy storage, biomedicine, and water purification

Colonic Delivery of α-Linolenic Acid by an Advanced Nutrient Delivery System Prolongs Glucagon-Like Peptide-1 Secretion and Inhibits Food Intake in Mice

ScopeNutrients stimulate the secretion of glucagon-like peptide-1 (GLP-1), an incretin hormone, secreted from enteroendocrine L-cells which decreases food intake. Thus, GLP-1 analogs are approved for the treatment of obesity, yet cost and side effects limit their use. L-cells are mainly localized in the distal ileum and colon, which hinders the utilization of nutrients targeting GLP-1 secretion. This study proposes a controlled delivery system for nutrients, inducing a prolonged endogenous GLP-1 release which results in a decrease food intake.Methods and Resultsα-Linolenic acid (αLA) was loaded into thermally hydrocarbonized porous silicon (THCPSi) particles. In vitro characterization and in vivo effects of αLA loaded particles on GLP-1 secretion and food intake were studied in mice. A total of 40.4 ± 3.2% of loaded αLA is released from particles into biorelevant buffer over 24 h, and αLA loaded THCPSi significantly increased in vitro GLP-1 secretion. Single-dose orally given αLA loaded mesoporous particles increased plasma active GLP-1 levels at 3 and 4 h and significantly reduced the area under the curve of 24 h food intake in mice.ConclusionsαLA loaded THCPSi particles could be used to endogenously stimulate sustain gastrointestinal hormone release and reduce food intake.</p

In Vitro Dissolution Methods for Hydrophilic and Hydrophobic Porous Silicon Microparticles

Porous silicon (PSi) is an innovative inorganic material that has been recently developed for various drug delivery systems. For example, hydrophilic and hydrophobic PSi microparticles have been utilized to improve the dissolution rate of poorly soluble drugs and to sustain peptide delivery. Previously, the well-plate method has been demonstrated to be a suitable in vitro dissolution method for hydrophilic PSi particles but it was not applicable to poorly wetting hydrophobic thermally hydrocarbonized PSi (THCPSi) particles. In this work, three different in vitro dissolution techniques, namely centrifuge, USP Apparatus 1 (basket) and well-plate methods were compared by using hydrophilic thermally carbonized PSi (TCPSi) microparticles loaded with poorly soluble ibuprofen or freely soluble antipyrine. All the methods showed a fast and complete or nearly complete release of both model compounds from the TCPSi microparticles indicating that all methods described in vitro dissolution equally. Based on these results, the centrifuge method was chosen to study the release of a peptide (ghrelin antagonist) from the THCPSi microparticles since it requires small sample amounts and achieves good particle suspendability. Sustained peptide release from the THCPSi microparticles was observed, which is in agreement with an earlier in vivo study. In conclusion, the centrifuge method was demonstrated to be a suitable tool for the evaluation of drug release from hydrophobic THCPSi particles, and the sustained peptide release from THCPSi microparticles was detected

Bisphosphonate modified mesoporous silicon for scandium adsorption

Scandium has several applications in advanced technology, but its wider utilization is restricted by the limited supply. Scandium exists in low concentration in ores and, therefore, the conventional extraction methods are difficult, uneconomical, and often hazardous to the environment. Adsorption is more sustainable method to extract scandium, because of low energy consumption and scalability. However, selectivity and stability of adsorbents are often inadequate. The present paper introduces a novel hybrid material as a robust adsorbent for efficient extraction of scandium. The material comprises of bisphosphonate molecules grafted on thermally carbonized surfaces of mesoporous silicon. The mesoporous framework was utilized to make the material water permeable to be used in a flow-through system, and the surface modifications made the material exceptionally stable even in harsh conditions. The material exhibited a remarkable selectivity towards scandium with a separation factor of 13, which is 3-fold higher compared with the commercial ion exchange resin Dowex 50WX8. Crucially, the hybrid material proved to be highly stable and reusable up to 50 adsorption/desorption cycles of scandium.final draftpeerReviewe