The [OIII]++Hβ\beta Equivalent Width Distribution at z≃\simeq7: Implications for the Contribution of Galaxies to Reionization

We quantify the distribution of [OIII]+H$\beta$ line strengths at z$\simeq$7 using a sample of 20 bright (M$_{\mathrm{UV}}$ $\lesssim$ $-$21) galaxies. We select these systems over wide-area fields (2.3 deg$^2$ total) using a new colour-selection which precisely selects galaxies at z$\simeq$6.63$-$6.83, a redshift range where blue Spitzer/IRAC [3.6]$-$[4.5] colours unambiguously indicate strong [OIII]$+$H$\beta$ emission. These 20 galaxies suggest a log-normal [OIII]$+$H$\beta$ EW distribution with median EW = 759$^{+112}_{-113}$ $\mathrm{\mathring{A}}$ and standard deviation = 0.26$^{+0.06}_{-0.05}$ dex. We find no evidence for strong variation in this EW distribution with UV luminosity. The typical [OIII]+H$\beta$ EW at z$\simeq$7 implied by our sample is considerably larger than that in massive star forming galaxies at z$\simeq$2, consistent with a shift toward larger average sSFR (4.4 Gyr$^{-1}$) and lower metallicities (0.16 Z$_\odot$). We also find evidence for the emergence of a population with yet more extreme nebular emission ([OIII]+H$\beta$ EW$>$1200 $\mathrm{\mathring{A}}$) that is rarely seen at lower redshifts. These objects have extremely large sSFR ($>$30 Gyr$^{-1}$), as would be expected for systems undergoing a burst or upturn in star formation. While this may be a short-lived phase, our results suggest that 20% of the z$\simeq$7 population has such extreme nebular emission, implying that galaxies likely undergo intense star formation episodes regularly at z$>$6. We argue that this population may be among the most effective ionizing agents in the reionization era, both in terms of photon production efficiency and escape fraction. We furthermore suggest that galaxies passing through this large sSFR phase are likely to be very efficient in forming bound star clusters.Comment: 20 pages, 11 figures. Accepted in MNRAS with minor revision

The flow rate sensitivity to voltage across four electrospray modes

The influence of potential difference on the emitted flow rate across four modes of electrospray is described for an unrestricted electrospray system. The modes are those most commonly occurring; enhanced dripping, pulsation, cone-jet, and multi-jet. It is demonstrated that within three of these modes, the effect of voltage on flow rate is generally linear, with similar magnitude of gradient across all. The effect is demonstrated to be calculable across these three modes. This finding highlights that in the absence of any flow control mechanism, the influence of electrostatic pressure in driving the flow is the key process in voltage-driven electrospray

Laptop Technology in Classrooms: How Student Perceptions Shape Learning and Satisfaction

This study is based on perceptions of students regarding the integration of laptops in classroom endeavors. Empirical findings are based on data collected from a sample of 392 students in undergraduate and graduate universities in twelve states of the USA. Three key findings related to the integration of laptop technology into classrooms of higher education are reported. First relates to student perceptions and feelings surrounding laptop use in the classroom. Secondly, we report how these perceptions vary depending on personal characteristics of students. Lastly, we examine the role these perceptions play in student learning, as well as student satisfaction. Traditionally, laptop technology has been viewed as tool for facilitating note taking. However, our findings indicate that the learning experience is equal, and in some instances greater, when laptops are used to develop a more interactive learning environment, increase information gathering during class time, and enhance classroom discussion

A qualitative examination of the social manifestations of participating in fantasy sports

As technology continues to infiltrate society, an increasing popularity of products like fantasy sports has become apparent. Fantasy sports are played yearly by millions of individuals across the world. This is a billion-dollar industry that does not appear to be slowing down anytime soon. Most scholarly attention has focused on participant’s motivation for playing fantasy sports. This qualitative study expands upon prior research on motivation. Little research has been conducted regarding the social dynamics of fantasy participation and leagues. In this research, multiple social manifestations of playing fantasy sports was uncovered. To gather a deep understanding of the overarching social dimensions of fantasy leagues, the author conducted semi-structured interviews with individuals who participate in annual leagues. The results of these interviews discovered that fantasy sports operate as a social tool to develop camaraderie between participants, keep them connected, and stimulate conversation. Additionally, both smack/bragging rights and nostalgia were significant aspects of the fantasy sport experience that subjects underscored. This study contributes to the fantasy sport literature as well as sport managers and marketers. The research is useful with such little examination done regarding fantasy sport leagues, and it compliments past research conducted on fantasy sport motivation. With research on fantasy sports in it’s infancy, this study, the first of its type, will serve those interested in learning more about the industry and its consumers

Utilizing the C2Maps Platform for Characterizing Drug-Protein Relations, Generating Mobile Games, and Constructing Integrated Pathway Models

poster abstractThe C2Maps platform is a collection of genome-wide data that display the connections between drugs, diseases and genes. The C2Maps is used as a tool to compare and extrapolate known map data into unknown areas. By using C2Maps, researchers can compare genetic, sequential and physical information about disease specific proteins. Manual curation is important for the C2Maps platform in order to validate the literature mining approach and to overcome high levels of data noise generated from molecular networks. Currently we are examining specific drug-protein relationships in several diseases. In this research, the C-Maps website is being used to manually curate abstracts about disease specific drugprotein relations and then it is determined whether a drug “Up Regulates”, “Down Regulates”, or “Indirectly” affects a specific protein. Presently, more than 2000 specific protein-drug relations have been examined through the platform. We theorize that new drug-protein relations will be discovered through curation efforts. To broaden the scope of curation data generated, a C2Maps mobile game is in the process of being developed. This game takes advantage of novel technology in mobile development to create a game that will allow several researchers to contribute to the curation process. The data generated from the manual curation approach can be used to validate various protein-drug relationships in pharmacology and can determine the best possible drugs targeting specific proteins in cancer. Optimal drugs and their respective targets for a specific disease can then be incorporated into an integrative pathway model to analyze the mechanism of the drug. Specific properties of the drug, including chemical structure, can then be examined to determine how a specific drug acts on particular target proteins

On the ages of bright galaxies ∼500\sim 500 Myr after the Big Bang: insights into star formation activity at z≳15z \gtrsim 15 with JWST

With JWST, new opportunities to study the formation and evolution of galaxies in the early Universe are now emerging. Spitzer constraints on rest-optical properties of $z \gtrsim 7$ galaxies demonstrated the power of using stellar masses and star formation histories (SFHs) of galaxies to indirectly infer the star formation history of the Universe. However, only the brightest individual objects at $z \gtrsim 8$ could be detected with Spitzer, making it difficult to robustly constrain past activity at $z \gtrsim 10$. Here, we leverage the greatly improved rest-optical sensitivity of JWST at $z \gtrsim 8$ to constrain the ages and SFHs of eleven UV-bright ($M_\text{UV} \lesssim -19.5$) galaxies selected to lie at $z \sim 8.5 - 11$, then investigate implications for star formation activity at $z \gtrsim 15$. We infer the properties of individual objects in our sample with two spectral energy distribution modelling codes, then infer a distribution of ages for bright $z \sim 8.5 - 11$ galaxies. We find a median age of $\sim 30$ Myr, younger than that inferred at $z \sim 7$ with a similar analysis, which is consistent with an evolution towards larger specific star formation rates at early times. The age distribution suggests that only $\sim 9$ percent of bright $z \sim 8.5 - 11$ galaxies would be similarly luminous at $z \gtrsim 15$, implying that the number density of bright galaxies declines by approximately an order of magnitude between $z \sim 8.5 - 11$ and $z \sim 15$. This evolution is challenging to reconcile with some early JWST results suggesting that the abundance of bright galaxies does not significantly decrease towards very early times, but we suggest this tension may be eased if young stellar populations form on top of older stellar components, or if bright galaxies at $z \sim 15$ are observed during a burst of star formation.Comment: 13 pages, 9 figure