Development of a UAV-Based System to Monitor Air Quality over an Oil Field

The growth of hydraulic fracturing has pushed the whole petroleum industries forward. As a result, gas (mainly methane [CH4]) emissions have significantly increased over the past decades (Macey et al., 2014). Gas leaks can occur at almost all stages of a petroleum production process, such as drilling, fracking, and refining. For years, ground-based air quality monitoring has been conducted around production sites. An improved understanding of air quality would be enabled by supplementing ground-based with airborne monitoring. The latter would involve the use of unmanned aerial vehicles (UAVs) to carry a compact, portable air monitoring system. The purpose of this study was to design and fabricate a UAV-based system for monitoring of CH4 and CO2, the two most important greenhouse gases, over oil fields. The system consisted of an airborne sensor node and a ground station. The sensor node was comprised of low-cost gas sensors, a microcontroller, a LoRa wireless transmitter, a GPS module, and an SD card shield. The ground station was comprised of a LoRa wireless receiver, a microcontroller, and a laptop. Both the sensor node and the ground station were programmed using Arduino IDE. A graphic user interface (GUI) was created using LabVIEW for data logging and visualization on the laptop. Preliminary trials near the university campus showed that the system was capable of measuring CH4 and CO2 concentrations in real time, along with temperature, relative humidity, and GPS location; while sending the monitoring data to the ground station (up to ~800 m away) every two seconds without any loss. The system was further tested at two oil production sites in North Dakota. The results revealed a heterogeneous distribution of CH4 and CO2 over the sites, demonstrating a potential application of the system for air quality survey and gas leakage detection. The advantage of this UAV-based monitoring system lies in its portability, expandability, lower cost, ease of deployment and operation. The overall cost of the system was below 300 dollars, and it weighed 540 grams, including enclosures. The system performance was limited by the selected gas sensors with relatively poorer sensitivity and slower response than regular gas monitors (which are bulkier and much more expensive). However, with the advancement in sensor technologies, it is expected that the quality of monitoring data from the UAV-based system can be considerably improved in the near future

Accounting narratives and impression management on social media

In this paper, we examine the defensive and assertive impression management strategies and the impact of firm performance on accounting narratives by investigating the earnings disclosures of FTSE 100 companies on Twitter. Social media has become the prevailing venue for organisational self-presentation because it provides firms with more control over the image they intend to establish and maintain through the communication and content they deliver online. Our findings show that firms minimise the disclosures of negative information but employ various patterns and dissemination techniques to emphasise positive information. Specifically, improving performers are more willing to post and disseminate earnings-related tweets to achieve a higher degree of stakeholder engagement than declining performers. Based on these findings, we conclude that firms present themselves on social media opportunistically to construct a positive public image

Induced Rules for Minimum Cost Spanning Tree Problems:towards Merge-proofness and Coalitional Stability

This paper examines cost allocation rules for minimum cost spanning tree (MCST) problems, focusing on the properties of merge-proofness and coalitional stability. Merge-proofness ensures that no coalition of agents has the incentive to merge before participating in the cost allocation process. On the other hand, coalitional stability ensures that no coalition has the incentive to withdraw from the cost allocation process after the cost allocation proposal is made. We propose a novel class of rules called induced rules, which are derived recursively from base rules designed for two-person MCST problems. We demonstrate that induced rules exhibit both merge-proofness and coalitional stability within a restricted domain, provided that the corresponding base rules satisfy specific conditions

Estereotipos de mujeres en el programa La juventud contigo 2 de iQIYI

La juventud contigo 2 es un talent show musical que se emitió en la plataforma iQIYI en 2020 en el que participaron exclusivamente mujeres. El programa consiguió grandes audiencias y atención del público porque parece dar una libertad sin precedentes a las concursantes para construir una imagen de la mujer diferente a la imagen tradicional de la mujer en los medios de comunicación. El propósito de este Trabajo fin de Máster es analizar cuáles son los estereotipos femeninos presentados en este espectáculo a través de la clasificación de López, García y Lajo (2006), así como averiguar cuál es el estereotipo de la concursante ganadora y si realmente cambian los estereotipos de la mujer en los medios de comunicación tradicionales. Los resultados permiten comprobar que existe una diversificación de la imagen femenina y que se rompe el estereotipo de mujer objeto sexual, habitual en la música, con una ganadora que corresponde más a la mujer andrógina."Youth with you 2", which aired on the iQIYI platform in 2020, has gained a lot of attention and has become a hot topic because of the innovation. The program seems to give unprecedented freedom to the contestants, which means that the program seems to build an image of women different from the traditional image of women in the media. Female awareness increases considerably, and the image of women seems to have been reconstructed in this program. However, it is questionable whether this show has really changed or reshaped the stereotypical image of women. The purpose of this paper is to determine the female stereotypes presented in this show and whether it really changes the stereotypes of women in traditional media or if women are still in the hegemony of men.Máster en Investigación de la Comunicación como Agente Histórico-Socia

Nanosheet-Assembled ZnO Microflower Photocatalysts

Large scale ZnO microflowers assembled by numerous nanosheets are synthesized through a facile and effective hydrothermal route. The structure and morphology of the resultant products are characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Photocatalytic properties of the as-synthesized products are also investigated. The results demonstrate that eosin red aqueous solution can be degraded over 97% after 110 min under UV light irradiation. In addition, methyl orange (MO) and Congo red (CR) aqueous solution degradation experiments also are conducted in the same condition, respectively. It showed that nanosheet-assembled ZnO microflowers represent high photocatalytic activities with a degradation efficiency of 91% for CR with 90 min of irradiation and 90% for MO with 60 min of irradiation. The reported ZnO products may be promising candidates as the photocatalysts in waste water treatment

Lack of interferon response in animals to naked siRNAs

RNA interference (RNAi) is rapidly becoming the method of choice for the elucidation of gene function and the identification of drug targets. As with other oligonucleotide-based strategies, RNAi is envisioned to ultimately be useful as a human therapeutic. Unlike previous nucleic acid therapeutics, small interfering RNAs have the potential to elicit immune responses via interactions with Toll-like receptor 3 and trigger interferon responses like long, double-stranded RNA and its analogs, such as poly(I:C). Recently, the safety of siRNAs has been questioned because they have been shown to trigger an interferon response in cultured cells. We show here that it is possible to administer naked, synthetic siRNAs to mice and downregulate an endogenous or exogenous target without inducing an interferon response

Recent Advance in Tumor Microenvironment-Based Stimuli-Responsive Nanoscale Drug Delivery and Imaging Platform

The tumor microenvironment (TME) plays an important role in the development, progression, and metastasis of cancer, and the extremely crucial feature is hypoxic and acidic. Cancer-associated fibroblasts (CAFs), extracellular matrix (ECM), mesenchymal cells, blood vessels, and interstitial fluid are widely recognized as fundamentally crucial hallmarks for TME. As nanotechnology briskly boomed, the nanoscale drug delivery and imaging platform (NDDIP) emerged and has attracted intensive attention. Based on main characteristics of TME, NDDIP can be classified into pH-sensitive delivery and imaging platforms, enzyme-sensitive delivery and imaging platforms, thermo-sensitive delivery and imaging platforms, redox-sensitive delivery and imaging platforms, and light-sensitive delivery and imaging platforms. Furthermore, imageology is one of the significant procedures for disease detection, image-guided drug delivery, and efficacy assessment, including magnetic resonance imaging (MRI), computed tomography (CT), ultrasound (US), and fluorescence imaging. Therefore, the stimuli-responsive NDDIP will be a versatile and practicable tumor disease diagnostic procedure and efficacy evaluation tool. In this review article, we mainly introduce the characteristics of TME and summarize the progress of multitudinous NDDIP as well as their applications