Depth Of Media Research Articles

Occurrence, Concentration, and Distribution of 35 PFASs and Their Precursors Retained in 20 Stormwater Biofilters.

Current knowledge about the fate and transport behaviors of per- and polyfluoroalkyl substances (PFASs) in urban stormwater biofilter facilities is very limited. C5-14,16 perfluoroalkyl carboxylic acids [perfluorinated carboxylic acids (PFCAs)], C4,8,10 perfluoroalkanesulfonic acids (PFSAs), methyl-perfluorooctane sulfonamide acetic acid (MeFOSAA, a PFSA precursor), and unknown C6-8 PFCA and perfluorooctanesulfonic acid precursors were frequently found in bioretention media and forebay sediments at Σ35PFAS concentrations of <0.03-19 and 0.064-16 μg/kg-DW, respectively. Unknown C6-8 PFCA precursor concentrations were up to ten times higher than the corresponding PFCAs, especially at forebays and biofilters' top layer. No significant trend could be attributed to PFAS and precursor concentrations versus depth of filter media, though PFAS concentrations were 2-3 times higher in the upper layers on average (significant difference between the upper (0-5 cm) and deepest (35-50 cm) layer). PFASs had a similar spatial concentration distribution in each filter media (no clear difference between short- and long-chain PFASs). Commercial land use and organic matter were important factors explaining the concentration variations among the biofilters and between the sampling depths, respectively. Given the comparable PFAS accumulations in deeper and superficial layers and possible increased mobility after precursor biotransformation, designing shallow-depth, nonamended sand biofilters or maintaining only the top layer may be insufficient for stormwater PFAS management.

THE INFLUENCE OF CONSUMERS, EMPLOYEES, MEDIA AND SHAREHOLDERS’ ENGAGEMENT ON THE QUALITY OF SUSTAINABILITY REPORTING IN INDONESIA

This study delves into the nuanced variables of sustainability reporting quality within the context of energy, basic materials, industrial, consumer non-cyclicals, consumer cyclicals, as well as transportation and logistics sectors. Employing a content analysis on companies’ reports, this research scrutinizes the depth and breadth of consumer, employee, media, and shareholders’ engagement on the quality sustainability reporting of companies listed on the IDX from the period of 2019-2022. In pursuit of these objectives, a quantitative study approach was employed. The research design encompasses content analysis to examine the quality of sustainability reporting from a representative sample of 45 organizations within the energy, basic materials, industrial, consumer non-cyclicals, consumer cyclicals, as well as transportation and logistics sectors. Additionally, in this research, the Multiple Logistic Regression analysis was used. The research findings underscore four key aspects; in regards to the hypotheses tested. All four variables- consumer, employee, media, and shareholders’ engagement- emerged as critical determinants impacting the quality of sustainability reporting. These findings contribute to the existing body of knowledge by offering practical implications for organizations aiming to elevate their sustainability reporting quality, thereby fostering a more transparent and responsible business environment.

Analysis of Coping Mechanisms and the Effects of Social Media on Teenagers

Adolescents' development of thought and conduct are severely impacted by the content on social media from both positive and negative aspects as a result of the development of numerous social media platforms in recent years. The purpose of the study is to determine the positive and negative influence of social media on teenagers and their coping strategies. The nature of social media, and conceptual theories such as filter bubbles, echo chambers, fear of missing out, the favourable and adverse effects of social media on adolescents and the corresponding strategies are all specifically investigated and evaluated in this study. Analytical research methodology and literature reviews are used to carry out the study to compile and summarise prior research related to adolescents use of social media. Data from earlier studies that are relevant to the study issue are gathered. The findings of this study provide reasons and instructions for parents and educators to discover and promptly address the harm that social media has caused to young people. The public should pay attention to the breadth and depth of social media's detrimental effects on teenagers.

Shear stress facilitates Akt activation in human pulmonary microvascular endothelial cells

Introduction: Pulmonary arterial obstruction due to acute thromboembolism causes local reduction or cessation of blood flow. Under normal conditions, pulmonary blood flow exerts shear stress on endothelial cells, known to play an important role in maintaining vascular homeostasis. We hypothesized that pulmonary microvascular endothelial cells exposed to abrupt reductions in shear stress would demonstrate attenuated phosphatidylinositol 3-kinase (PI3K)-dependent signaling and phosphorylation of downstream effectors Akt and endothelial nitric oxide synthase (eNOS). Methods: We tested our hypothesis in primary cultures of human lung microvascular endothelial cells (hLMVECs). We cultured early passage (p≤8) hLMVECs from 5 unique donor lots in standard 6-well culture plates and exposed cells to shear stress using an orbital shaker. Using a fixed depth (volume) and viscosity of tissue culture media, we adjusted the magnitude of shear stress exerted on hLMVECs by changing the angular velocity of orbital rotation. We acclimatized hLMVECs to physiologically-relevant shear stress (~12 dyn/cm 2 ) for 24 hours, then exposed cells to low shear stress (~3 dyn/cm 2 ) or no shear stress (0 dyn/cm 2 ) for 30 minutes. Control cells were maintained at 12 dyn/cm 2 of shear stress. In some experiments, PI3K activity was inhibited throughout the acclimatization and shear stress manipulation period by including LY294002 (10 μM) or vehicle (DMSO, 0.1% v/v) in culture media. We prepared whole cell lysates and used western blot to evaluate the expression and phosphorylation of Akt (ser473) and eNOS (ser1177). Results: We found that phosphorylation of Akt, but not Akt expression, decreased significantly (p&lt;0.05) when shear stress was acutely reduced (~3 dyn/cm 2 ) or removed (0 dyn/cm 2 ). Inhibition of PI3K activity with LY294002 further diminished shear-mediated changes in Akt phosphorylation in all 3 groups. Conversely, eNOS phosphorylation was not modified by acute reductions in shear stress, but eNOS expression was markedly attenuated by PI3K inhibition under all conditions. Conclusions: Our results indicate that phosphorylation of Akt, but not its downstream target eNOS, is rapidly attenuated by abrupt reductions in shear stress in hLMVECs. However, shear stress appears to regulate eNOS expression in a PI3K-dependent manner. Taken together, these findings suggest that acute disruption of flow, as seen in pulmonary embolism, may disrupt human lung microvascular endothelial cell homeostasis and nitric oxide bioavailability via multiple PI3K-dependent signaling pathways. This work is supported by HL126514 and HL159906. This is the full abstract presented at the American Physiology Summit 2023 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

REMOVAL OF FLUORIDE FROM DRINKING WATER THROUGH LOW-COST TECHNIQUES

Fluoride ions (F-) from natural sources or industrial wastewater are the main cause of many pathological conditions in people living in more than 25 countries. Thus, removing F- from drinking water is pivotal for preventing serious health consequences. The WHO recommends a limit of 1,5 mg/L for fluoride in drinking. Excessive amounts of fluoride in drinking water are prevalent in Pakistan, leading to related health risks. Low-cost techniques for the defluoridation of drinking water can be used. In this study, the removal of fluoride from drinking water by an adsorption method using low-cost materials/adsorbents, such as marble chips, wheat husks, rice husks, egg shells, concrete, fuller earth, fly ash, freshly fired bricks, and charcoal, at different contact times and different bed thicknesses were investigated. A batch sampling technique was used for sample collection. On average, marble chips, wheat husks, rice husks, egg shells, concrete, fuller earth, fly ash, freshly fired bricks, and activated charcoal (rice husk) resulted in 71,99 %; 90,99 %; 66,73 %; 90,99 %; 63,30 %; 71,99 %; 22,60 %; 49,67 %; and 90,13 % fluoride removal, respectively. Therefore, defluoridation using these materials is desirable. The performance of adsorbents depends on parameters such as contact time, depth of the adsorbent media, and pH. The bed thickness of the adsorbent has a minor effect on fluoride removal. The major contributors to fluoride removal from water are contact time and adsorbent composition.

Optimization of depth of filler media in horizontal flow constructed wetlands for maximizing removal rate coefficients of targeted pollutant(s)

Varying the depth of HFCW media causes differences in the redox status within the system, and hence the community structure and diversity of bacteria, affecting removal rates of different pollutants. The key functional microorganisms of CWs that remove contaminants belong to the phyla Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes. Secondary data of 111 HFCWs (1232 datasets) were analyzed to deduce the relationship between volumetric removal rate coefficients (KBOD, KTN, KTKN, and KTP) and depth. Equations of depth were derived in terms of rate coefficients using machine learning approach (MLR and SVR) (R2 = 0.85, 0.87 respectively). These equations were then used to find the optimum depth for pollutant(s) removal using Grey wolf optimization (GWO). The computed optimum depths were 1.48, 1.71, 1.91, 2.09, and 2.14 m for the removal of BOD, TKN, TN, TP, and combined nutrients, respectively, which were validated through primary data. This study would be helpful for optimal design of HFCWs.

Spatial correlation of groundwater pollutants with the vulnerability index in Kano Metropolis, North-western Nigeria

Abstract This study performed a correlation analysis between groundwater quality parameters with organic and inorganic pollutants using the area under the curve (AUC) of the receiver operating characteristics (ROC) map in Kano Metropolis, North-western Nigeria. The aim is to present the spatial relationship between groundwater pollutants and the existing vulnerability condition of the groundwater resources with a view to developing a vulnerability risk map. Eight water quality parameters (Ca, Al, Cl, NO3, TH, Mg, TDS which include potassium and sodium) and pH were used to develop the water quality index to represent the general overview of the groundwater pollutants. Vulnerability parameters (depth of water, net recharge, aquifer media and groundwater conferment on sensitivity analysis) were used as reference points for preparing ROC. Inorganic pollutants and hydrocarbons representing organic pollutants were integrated into the analysis process with a view to identifying their influence on the groundwater pollution level in the area. The measured AUC under ROC revealed a positive correlation between groundwater vulnerability with organic (63.7%) and inorganic pollutants (65.6%). Vulnerability risk mapping based on hydrocarbon concentration revealed a high level of pollution risk, especially in the core centre of the metropolitan Kano. HIGHLIGHT Groundwater pollution and vulnerability studies are one of the key issues in water resources management, especially in areas with a high level of risk of groundwater pollution such as metropolitan areas (Kano Metropolis inclusive) with a high rising population.

Journalism Transformation: Print Media Towards the Digitalization Era for Generation X

Print media has advantages that do not exist in online media in the form of ease of reading anywhere without having to access the internet. The depth of print media in writing news in more detail, not with online media which prioritizes the speed of news presentation. The presence of technology for generation X is actually an extraordinary thing, but it also demands to have to master technology that is experiencing accelerated technological progress. The most significant characteristic difference in generation X with other generations is the mastery of information and technology. The purpose of this study was to identify and analyze the transformation of journalism: print media into the digitalization era for generation X. The research method used was descriptive qualitative, all facts and social phenomena, and field observations were carried out and then analyzed based on what was observed. Data analysis in qualitative research is carried out simultaneously with the data collection process. Qualitative data analysis begins with analysis as data that researchers have collected in the field. The data is good through literature study. The results of the study describe the transformation of journalism: print media towards the era of digitization in generation X provides faster things, but for the generation they still have doubts about their abilities. It requires a deeper form of trust in print media, so that with the advent of digital media, it is hoped that the content of news and information will be the same. That what is written in print media can be read in the world of digital media with just the touch of a finger.

Measuring the implementation of media literacy statewide: a validation study

ABSTRACT Even though media literacy education has grown in the United States and around the world, policymakers still lack knowledge about the scope and depth of implementation of media literacy learning activities in the elementary and secondary grades. This study reports how the Media Literacy Implementation Index (MLI) was developed and validated using a quota sample of stakeholders from across all school districts and local communities in Rhode Island. Using an established theoretical framework for media literacy, we first constructed a scale to examine the likelihood that learners may encounter a set of media literacy learning activities. Multiple methods were then used to assess reliability and validity of the instrument including cognitive pretesting, think aloud protocols, a content validation of MLI learning activities in relation to national education standards documents, and statistical validation including principal components analysis to assess internal consistency, reliability, and validity. An easy-to-implement measure of the scope and depth of media literacy education in elementary and secondary schools will be useful to diverse stakeholders including educators, school leaders, librarians, parents, community members, and elected public officials.

Accumulation of heavy metals in stormwater biofiltration systems augmented with zeolite and fly ash

The discharge of high levels of heavy metals into the environment is of concern due to its toxicity to aquatic life and potential human health impacts. Biofiltration systems have been used in urban environments to address nutrient contamination, but there is also evidence that such systems can be effective in reducing heavy metals concentration in stormwater. However, the accumulation pattern of heavy metals and lifespan of such systems, which are important in engineering design, have not been thoroughly explored. This study investigated the accumulation patterns of lead (Pb), copper (Cu), zinc (Zn), manganese (Mn), and iron (Fe), which are common in urban runoff, in non-vegetated filtration columns using three different types of filter media, namely sand (S), and mixtures of sand with fly ash (sand-fly ash mix, SF), and with zeolite (sand-zeolite mix, SZ). The columns were assessed in terms of infiltration rate, the mass of heavy metals accumulation at different depths, and formation of crust layer (schmutzdecke) at the surface. The results show that most of the heavy metals accumulated at the top 5–10 cm of the filter media. However, Zn was found adsorbed to a depth of 15 cm in S and SZ columns, while Mn and Fe were present in column S throughout the entire 30 cm depth of the filter media. The presence especially of Zn, Mn, and Fe in the deeper portions of the filter media before the top 5 cm layer reached its maximum adsorption capacity, hints that transport to the deeper layers is not necessarily dependent on saturation of the upper layers for these heavy metals. SF accumulated heavy metals most at the top 5 cm of the filter media layer, and retained twice the mass of heavy metals in the crust layer, compared to S and SZ columns. SF also yielded the lowest value of infiltration rate of 31 mm/h. Considering both metals accumulation and clogging potential of the filter media, the periodic maintenance of these systems is suggested to be approximately between 1.5 and 3 years.

Factors affecting the hydrological response of substrate material for green roofs and bioretention

Green roof and bioretention have been frequently used as stormwater management practices to address urban hydrology issues, and researches regarding these technologies are increasing lately. However, a knowledge gap remains in characterizing the hydraulic properties of these practices. The hydrological process of green roof and bioretention is mainly determined by the substrate media of the practices. Based on current studies, this paper discussed factors affecting the hydrological response of substrate material for green roofs and bioretention. Most researches provide qualitative information on water movement within substrate, but few have further investigated the theoretical explanations on the hydrological process of substrate and give quantitative data. This study proposed that following factors affecting water flow dynamics of substrate media: type of materials and composition of the materials; depth of the substrate media; pore structure/network of the substrate materials. Many investigations focus on the effect of a single factor and generalizing the other, but the hydrological process of the substrate material is mostly under the effect of multiple factors simultaneously. And under different study conditions and different designs of green roof or bioretention, the importance of these factors to the hydrological performance of substrate media is different. In addition, interrelationships exist among the factors, changes in one factor could influence other factors. Current research on the factors influencing the hydrological process of the substrate material needs to be related. Future study needs to consider the effect of multiple factors and their interrelations, to create integrated approaches for a better understanding of the hydrological process of the substrate material, and for modeling the hydrological performance of the green roof and bioretention more accurately and designing the practices more efficient.

Analysis of Short Video Production and Dissemination from the Perspective of Mobile Multimedia

The expansion of the new media platform has further stimulated the diversified development of content production, with various media permeating each other and products merging with each other, thus broadening the depth of media. With the rapid popularization of the Internet and the wide application of social software, the social environment has become more free and efficient. People use mobile multimedia to realize free communication from space, express their right to speak effectively, and change the way people get information. With the continuous development of network economy, all kinds of short videos have gradually appeared in modern people’s life, adding fun to the people’s lifestyle and enriching the forms of people’s life and entertainment. Only by exploring the construction of short video communication mode can we better reveal the real veil of how short video is popular in the new media era. This paper starts with the phenomenon of mobile short video transmission, studies and analyzes the problems of mobile short video platform, and explores the coping strategies for its development.

Vulnerability assessment, transport modeling and simulation of nitrate in groundwater using SI method and modflow-MT3DMS software: case of Sminja aquifer, Tunisia

Like most North African countries, Tunisia is characterized by a harsh arid and semi-arid climate with scarce water resources and poor water quality on most of its territory. The quality of groundwater is not immune to pollution. Sminja aquifer, located in Zaghouan district in Northeastern Tunisia, has been used to meet Zaghouan agglomeration needs for drinking purposes and irrigation uses. On the other hand, the region has suffered from inefficient usage and mismanagement of water resource due to appropriate legal, political, and economic frameworks to take into consideration the regional vulnerability to climate change and population growth. The application of the Susceptibility Index (SI) makes it possible to evaluate the impact of agricultural activities on the water quality in Sminja aquifer, using five parameters [depth of water (D), net recharge (R), aquifer media (A), topography (T) and Land use (LU)]. Modular three-dimensional multispecies transport model was used to assess, simulate and predict pollution transport of nitrate. The vulnerability index's spatial distribution shows that the most vulnerable area was found in the extreme north of the Sminja aquifer. It shows that a high vulnerability characterizes 21% of the study area (70 < SI < 60). The moderate to high vulnerability areas to pollution occupied 12% of the aquifer and the moderate to low vulnerability zones occupied 67% of the total area. The outputs of the SI reflect a good correlation with the measured nitrate concentrations. After calibration completion, the MT3DMS transport model results showed a good correlation between measured and simulated nitrate concentrations. The predict scenarios show that the nitrate propagates in all the aquifer, from the irrigated area to the non-irrigated area.

Shallow Sand Equations: Real-Time Height Field Simulation of Dry Granular Flows.

Granular media is the second-most-manipulated substance on Earth, second only to water. However, simulation of granular media is still challenging due to the complexity of granular materials and the large number of discrete solid particles. As we know, dry granular materials could form a hybrid state between a fluid and a solid, therefore we propose a two-layer model and divide the simulation domain into a dilute layer, where granules can move freely as a fluid, and a dense layer, where granules act more like a solid. Motivated by the shallow water equations, we derive a set of shallow sand equations for modeling dry granular flows by depth-integrating three-dimensional governing equations along its vertical direction. Unlike previous methods for simulating a 2D granular media, our model does not restrict the depth of the granular media to be shallow anymore. To allow efficient fluid-solid interactions, we also present a ray casting algorithm for one-way solid-fluid coupling. Finally, we introduce a particle-tracking method to improve the visual representation. Our method can be efficiently implemented based on a height field and is fully compatible with modern GPUs, therefore allows us to simulate large-scale dry granular flows in real time.

Fabrication and characteristics of self‐aggregation nanoparticles used for conformance control treatment

In order to alleviate the contradiction between injectability of the profile control agent and its profile control performance, a novel core‐shell heterogeneous structure colloidal particles (CSA) were synthesized, and the mechanism of self‐aggregation plugging was proposed. Cross‐linking inside the nanoparticles and chain‐growth polymerization via capturing acrylamide in the aqueous phase result in the formation of core‐shell heterogeneous structures as proved by TEM observation and XPS analysis. Moreover, CSA nanoparticles exhibit good hydrophilic properties, outstanding thermal stability and limited expansion capacity. Effects of different metal cations and surface group on the self‐aggregation time of CSA nanoparticles were systematically studied. Results showed that divalent cations contributed to more significant aggregation of CSA nanoparticles in comparison to monovalent cations. The increasing cations concentration and valency decreased the thickness of electric double layer, which lead to a decrease in the zeta potential. Core flooding test shows that the injection of nanoparticles which diameter is much smaller that of pore‐throats into the target reservoir can not only successfully enter the depth of porous media, but also effectively block the high permeability areas by the formation of self‐aggregation particle clusters. This study provides a new method for the equilibrium between nanoparticles injectivity and in‐depth profile control of nanoparticles.

An Updated and Expanded Nationwide Study of Business Communication Courses

This nationwide study of business communication instructors examined course delivery, course outlook, topics and depth of coverage, social media and technology coverage, diversity coverage, critical thinking, and accessibility. The outlook for the course appears positive and promising, and instructors continue to add content to the course. An important finding is that business communication instructors’ level of confidence in technology significantly affects how they cover technology-mediated communication. Therefore, we suggest professional associations and higher education institutions should provide more opportunities for voluntary training in these newer communication technologies. Further research is needed about the strain placed on business communication instructors.

Consequences of fluctuating depth of filter media on coliform removal performance and effluent reuse opportunities of a bio-sand filter in municipal wastewater treatment

Abstract Due to the rapid urbanization attaining full coverage of proper wastewater treatment is a challenge in several developing nations. The conventional sanitattion approachpracticed in different countries does not satisfy the current wastewater treatment need of fastly growing cities. Also, the decentralized technologies practiced so far is interrupted by technical issues that ends in an extensive upsurge of maintenance cost and poor effluent quality. Thus, this study focuses on the applicability of low-cost bio-sand filters as a decentralized municipal wastewater treatment technology through testing pathogen removal efficiency and effluent reuse possibilities of different media depth bio-sand filters. Three setups of bio-sand filtercolumn were established each comprised of a specific sand, fine gravel and coarse gravel with different filter depths. The results orevealed geometric mean reductions for total coliforms of 99 %, 87 % and 30 % for a bio-sand filter with the top fine sand depth of 220 mm, 120 mm, and 20 mm, respectively. While the geometric mean for the reduction of fecal coliform was 99.9 %, 99.6 %, and 99 %. The effluent from three of the bio-sand filters does not achieve the requirements for unrestricted irrigation according to WHO and US-EPA guidelines. Whereas the quality of effluent from the first scenario of the bio-sand filter can meet WHO and US-EPA guidelines for restricted irrigation reuse option. Likewise, the effluent from the second scenario of the bio-sand filter achieves the US-EPA reuse standard for restricted irrigation.

Experimental Investigation of the Influence for Stoping Sequence and Granular Grading on Lateral Pressure during the Nonpillar Sublevel Caving Mining

In this study, a self‐designed scaled physical model was conducted to investigate the variation laws of lateral pressure under different stoping sequences and granular gradings, and drawing ore in the experiments was used to simulate the mining process. Under the limiting equilibrium state, the values of lateral pressure increased exponentially with the increasing depth of granular media, and the growth rate of lateral pressure gradually decreased as the depth of granular media increased. Then, the laboratory results indicated that the distribution laws of lateral pressure were divided into three parts, namely, the drawing influencing region, the upper descending zone, and the central growth area. As the height of the isolated extraction zone (IEZ) increased, the scope of the drawing influencing region and the upper descending zone increased, while the range of central growth area decreased. In the case of an invariable height of IEZ, more reduction ratio and the scope for drawing influencing region could be appeared in the lower wall. Increasing the space between the drawpoints and granular grading were an effective way to control the reduction rate of lateral pressure in the drawing influencing region, while the scope of the above parts kept stable. Moreover, the average values of lateral pressure showed an increasing trend as the granular grading decreased at the same number of drawing ore.

Measurements of wall-media contact forces and work in a vibratory finisher

The bulk flow and local impact velocities of loose abrasive particles in vibratory finishing operations have been explained in the literature in terms of the forces exerted by the vibrating container walls. In the present work, these forces were measured using a force sensor embedded in the walls of a vibrating tub finisher loaded with various amounts of steel media and subject to different vibration frequencies. It was found that wall-media contact forces increased with the depth of media above the sensor and with the normal wall velocity, which explained why wall forces remained approximately unchanged with varying media mass, but increased with increasing tub frequency. The average impulse of the wall on the media increased with increasing media mass and decreased with increasing frequency of vibration. The work done by the walls was also measured and was found to increase with increasing tub frequency for a fixed media mass.

Firm-level perspectives on social media engagement: an exploratory study

PurposeThis paper aims to develop a richer, more complete understanding of how firms define and consider customer engagement on social networks. The research builds from the theoretical backdrop of customer engagement. The research then uses a qualitative interview approach to understand the firm perspective.Design/methodology/approachQualitative data were collected using in-depth interviews with employees at a variety of companies including Facebook, Google, another leading social networking site, a higher education institution and a start-up company.FindingsCompanies view engagement with social media as measureable metrics of consumer interactions with the platform. These metrics could include growth and interaction on the platform, number of users, subscribers to the site or page views. Propositions are developed around how customer engagement is defined, the breadth and depth of social media and when social media is used as a push or a pull strategy.Research limitations/implicationsFindings from this research are limited by the sample size and convenience of sampling. However, results from this grounded theory approach enabled propositions that can focus on larger datasets and testing.Practical implicationsEngagement indicates meaningful information that can propel a company’s position forward. To companies, this meaningful information is in terms of metrics that can be used as information and evidence for future decision-making.Social implicationsThis research suggests that firms need to better define what engagement means and to assess the best platforms for creating an ecosystem of engagement with customers.Originality/valueMany researchers are exploring engagement within the context of social media networks. This research, however, is one of the first to explore this from a firm level perspective.